Update vendor github.com/prometheus/common/...

vendor/github.com/alecthomas/template/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/alecthomas/template/README.md

@@ -0,0 +1,25 @@
+# Go's `text/template` package with newline elision
+
+This is a fork of Go 1.4's [text/template](http://golang.org/pkg/text/template/) package with one addition: a backslash immediately after a closing delimiter will delete all subsequent newlines until a non-newline.
+
+eg.
+
+```
+{{if true}}\
+hello
+{{end}}\
+```
+
+Will result in:
+
+```
+hello\n
+```
+
+Rather than:
+
+```
+\n
+hello\n
+\n
+```

vendor/github.com/alecthomas/template/doc.go

@@ -0,0 +1,406 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package template implements data-driven templates for generating textual output.
+
+To generate HTML output, see package html/template, which has the same interface
+as this package but automatically secures HTML output against certain attacks.
+
+Templates are executed by applying them to a data structure. Annotations in the
+template refer to elements of the data structure (typically a field of a struct
+or a key in a map) to control execution and derive values to be displayed.
+Execution of the template walks the structure and sets the cursor, represented
+by a period '.' and called "dot", to the value at the current location in the
+structure as execution proceeds.
+
+The input text for a template is UTF-8-encoded text in any format.
+"Actions"--data evaluations or control structures--are delimited by
+"{{" and "}}"; all text outside actions is copied to the output unchanged.
+Actions may not span newlines, although comments can.
+
+Once parsed, a template may be executed safely in parallel.
+
+Here is a trivial example that prints "17 items are made of wool".
+
+	type Inventory struct {
+		Material string
+		Count    uint
+	}
+	sweaters := Inventory{"wool", 17}
+	tmpl, err := template.New("test").Parse("{{.Count}} items are made of {{.Material}}")
+	if err != nil { panic(err) }
+	err = tmpl.Execute(os.Stdout, sweaters)
+	if err != nil { panic(err) }
+
+More intricate examples appear below.
+
+Actions
+
+Here is the list of actions. "Arguments" and "pipelines" are evaluations of
+data, defined in detail below.
+
+*/
+//	{{/* a comment */}}
+//		A comment; discarded. May contain newlines.
+//		Comments do not nest and must start and end at the
+//		delimiters, as shown here.
+/*
+
+	{{pipeline}}
+		The default textual representation of the value of the pipeline
+		is copied to the output.
+
+	{{if pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, T1 is executed.  The empty values are false, 0, any
+		nil pointer or interface value, and any array, slice, map, or
+		string of length zero.
+		Dot is unaffected.
+
+	{{if pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, T0 is executed;
+		otherwise, T1 is executed.  Dot is unaffected.
+
+	{{if pipeline}} T1 {{else if pipeline}} T0 {{end}}
+		To simplify the appearance of if-else chains, the else action
+		of an if may include another if directly; the effect is exactly
+		the same as writing
+			{{if pipeline}} T1 {{else}}{{if pipeline}} T0 {{end}}{{end}}
+
+	{{range pipeline}} T1 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, nothing is output;
+		otherwise, dot is set to the successive elements of the array,
+		slice, or map and T1 is executed. If the value is a map and the
+		keys are of basic type with a defined order ("comparable"), the
+		elements will be visited in sorted key order.
+
+	{{range pipeline}} T1 {{else}} T0 {{end}}
+		The value of the pipeline must be an array, slice, map, or channel.
+		If the value of the pipeline has length zero, dot is unaffected and
+		T0 is executed; otherwise, dot is set to the successive elements
+		of the array, slice, or map and T1 is executed.
+
+	{{template "name"}}
+		The template with the specified name is executed with nil data.
+
+	{{template "name" pipeline}}
+		The template with the specified name is executed with dot set
+		to the value of the pipeline.
+
+	{{with pipeline}} T1 {{end}}
+		If the value of the pipeline is empty, no output is generated;
+		otherwise, dot is set to the value of the pipeline and T1 is
+		executed.
+
+	{{with pipeline}} T1 {{else}} T0 {{end}}
+		If the value of the pipeline is empty, dot is unaffected and T0
+		is executed; otherwise, dot is set to the value of the pipeline
+		and T1 is executed.
+
+Arguments
+
+An argument is a simple value, denoted by one of the following.
+
+	- A boolean, string, character, integer, floating-point, imaginary
+	  or complex constant in Go syntax. These behave like Go's untyped
+	  constants, although raw strings may not span newlines.
+	- The keyword nil, representing an untyped Go nil.
+	- The character '.' (period):
+		.
+	  The result is the value of dot.
+	- A variable name, which is a (possibly empty) alphanumeric string
+	  preceded by a dollar sign, such as
+		$piOver2
+	  or
+		$
+	  The result is the value of the variable.
+	  Variables are described below.
+	- The name of a field of the data, which must be a struct, preceded
+	  by a period, such as
+		.Field
+	  The result is the value of the field. Field invocations may be
+	  chained:
+	    .Field1.Field2
+	  Fields can also be evaluated on variables, including chaining:
+	    $x.Field1.Field2
+	- The name of a key of the data, which must be a map, preceded
+	  by a period, such as
+		.Key
+	  The result is the map element value indexed by the key.
+	  Key invocations may be chained and combined with fields to any
+	  depth:
+	    .Field1.Key1.Field2.Key2
+	  Although the key must be an alphanumeric identifier, unlike with
+	  field names they do not need to start with an upper case letter.
+	  Keys can also be evaluated on variables, including chaining:
+	    $x.key1.key2
+	- The name of a niladic method of the data, preceded by a period,
+	  such as
+		.Method
+	  The result is the value of invoking the method with dot as the
+	  receiver, dot.Method(). Such a method must have one return value (of
+	  any type) or two return values, the second of which is an error.
+	  If it has two and the returned error is non-nil, execution terminates
+	  and an error is returned to the caller as the value of Execute.
+	  Method invocations may be chained and combined with fields and keys
+	  to any depth:
+	    .Field1.Key1.Method1.Field2.Key2.Method2
+	  Methods can also be evaluated on variables, including chaining:
+	    $x.Method1.Field
+	- The name of a niladic function, such as
+		fun
+	  The result is the value of invoking the function, fun(). The return
+	  types and values behave as in methods. Functions and function
+	  names are described below.
+	- A parenthesized instance of one the above, for grouping. The result
+	  may be accessed by a field or map key invocation.
+		print (.F1 arg1) (.F2 arg2)
+		(.StructValuedMethod "arg").Field
+
+Arguments may evaluate to any type; if they are pointers the implementation
+automatically indirects to the base type when required.
+If an evaluation yields a function value, such as a function-valued
+field of a struct, the function is not invoked automatically, but it
+can be used as a truth value for an if action and the like. To invoke
+it, use the call function, defined below.
+
+A pipeline is a possibly chained sequence of "commands". A command is a simple
+value (argument) or a function or method call, possibly with multiple arguments:
+
+	Argument
+		The result is the value of evaluating the argument.
+	.Method [Argument...]
+		The method can be alone or the last element of a chain but,
+		unlike methods in the middle of a chain, it can take arguments.
+		The result is the value of calling the method with the
+		arguments:
+			dot.Method(Argument1, etc.)
+	functionName [Argument...]
+		The result is the value of calling the function associated
+		with the name:
+			function(Argument1, etc.)
+		Functions and function names are described below.
+
+Pipelines
+
+A pipeline may be "chained" by separating a sequence of commands with pipeline
+characters '|'. In a chained pipeline, the result of the each command is
+passed as the last argument of the following command. The output of the final
+command in the pipeline is the value of the pipeline.
+
+The output of a command will be either one value or two values, the second of
+which has type error. If that second value is present and evaluates to
+non-nil, execution terminates and the error is returned to the caller of
+Execute.
+
+Variables
+
+A pipeline inside an action may initialize a variable to capture the result.
+The initialization has syntax
+
+	$variable := pipeline
+
+where $variable is the name of the variable. An action that declares a
+variable produces no output.
+
+If a "range" action initializes a variable, the variable is set to the
+successive elements of the iteration.  Also, a "range" may declare two
+variables, separated by a comma:
+
+	range $index, $element := pipeline
+
+in which case $index and $element are set to the successive values of the
+array/slice index or map key and element, respectively.  Note that if there is
+only one variable, it is assigned the element; this is opposite to the
+convention in Go range clauses.
+
+A variable's scope extends to the "end" action of the control structure ("if",
+"with", or "range") in which it is declared, or to the end of the template if
+there is no such control structure.  A template invocation does not inherit
+variables from the point of its invocation.
+
+When execution begins, $ is set to the data argument passed to Execute, that is,
+to the starting value of dot.
+
+Examples
+
+Here are some example one-line templates demonstrating pipelines and variables.
+All produce the quoted word "output":
+
+	{{"\"output\""}}
+		A string constant.
+	{{`"output"`}}
+		A raw string constant.
+	{{printf "%q" "output"}}
+		A function call.
+	{{"output" | printf "%q"}}
+		A function call whose final argument comes from the previous
+		command.
+	{{printf "%q" (print "out" "put")}}
+		A parenthesized argument.
+	{{"put" | printf "%s%s" "out" | printf "%q"}}
+		A more elaborate call.
+	{{"output" | printf "%s" | printf "%q"}}
+		A longer chain.
+	{{with "output"}}{{printf "%q" .}}{{end}}
+		A with action using dot.
+	{{with $x := "output" | printf "%q"}}{{$x}}{{end}}
+		A with action that creates and uses a variable.
+	{{with $x := "output"}}{{printf "%q" $x}}{{end}}
+		A with action that uses the variable in another action.
+	{{with $x := "output"}}{{$x | printf "%q"}}{{end}}
+		The same, but pipelined.
+
+Functions
+
+During execution functions are found in two function maps: first in the
+template, then in the global function map. By default, no functions are defined
+in the template but the Funcs method can be used to add them.
+
+Predefined global functions are named as follows.
+
+	and
+		Returns the boolean AND of its arguments by returning the
+		first empty argument or the last argument, that is,
+		"and x y" behaves as "if x then y else x". All the
+		arguments are evaluated.
+	call
+		Returns the result of calling the first argument, which
+		must be a function, with the remaining arguments as parameters.
+		Thus "call .X.Y 1 2" is, in Go notation, dot.X.Y(1, 2) where
+		Y is a func-valued field, map entry, or the like.
+		The first argument must be the result of an evaluation
+		that yields a value of function type (as distinct from
+		a predefined function such as print). The function must
+		return either one or two result values, the second of which
+		is of type error. If the arguments don't match the function
+		or the returned error value is non-nil, execution stops.
+	html
+		Returns the escaped HTML equivalent of the textual
+		representation of its arguments.
+	index
+		Returns the result of indexing its first argument by the
+		following arguments. Thus "index x 1 2 3" is, in Go syntax,
+		x[1][2][3]. Each indexed item must be a map, slice, or array.
+	js
+		Returns the escaped JavaScript equivalent of the textual
+		representation of its arguments.
+	len
+		Returns the integer length of its argument.
+	not
+		Returns the boolean negation of its single argument.
+	or
+		Returns the boolean OR of its arguments by returning the
+		first non-empty argument or the last argument, that is,
+		"or x y" behaves as "if x then x else y". All the
+		arguments are evaluated.
+	print
+		An alias for fmt.Sprint
+	printf
+		An alias for fmt.Sprintf
+	println
+		An alias for fmt.Sprintln
+	urlquery
+		Returns the escaped value of the textual representation of
+		its arguments in a form suitable for embedding in a URL query.
+
+The boolean functions take any zero value to be false and a non-zero
+value to be true.
+
+There is also a set of binary comparison operators defined as
+functions:
+
+	eq
+		Returns the boolean truth of arg1 == arg2
+	ne
+		Returns the boolean truth of arg1 != arg2
+	lt
+		Returns the boolean truth of arg1 < arg2
+	le
+		Returns the boolean truth of arg1 <= arg2
+	gt
+		Returns the boolean truth of arg1 > arg2
+	ge
+		Returns the boolean truth of arg1 >= arg2
+
+For simpler multi-way equality tests, eq (only) accepts two or more
+arguments and compares the second and subsequent to the first,
+returning in effect
+
+	arg1==arg2 || arg1==arg3 || arg1==arg4 ...
+
+(Unlike with || in Go, however, eq is a function call and all the
+arguments will be evaluated.)
+
+The comparison functions work on basic types only (or named basic
+types, such as "type Celsius float32"). They implement the Go rules
+for comparison of values, except that size and exact type are
+ignored, so any integer value, signed or unsigned, may be compared
+with any other integer value. (The arithmetic value is compared,
+not the bit pattern, so all negative integers are less than all
+unsigned integers.) However, as usual, one may not compare an int
+with a float32 and so on.
+
+Associated templates
+
+Each template is named by a string specified when it is created. Also, each
+template is associated with zero or more other templates that it may invoke by
+name; such associations are transitive and form a name space of templates.
+
+A template may use a template invocation to instantiate another associated
+template; see the explanation of the "template" action above. The name must be
+that of a template associated with the template that contains the invocation.
+
+Nested template definitions
+
+When parsing a template, another template may be defined and associated with the
+template being parsed. Template definitions must appear at the top level of the
+template, much like global variables in a Go program.
+
+The syntax of such definitions is to surround each template declaration with a
+"define" and "end" action.
+
+The define action names the template being created by providing a string
+constant. Here is a simple example:
+
+	`{{define "T1"}}ONE{{end}}
+	{{define "T2"}}TWO{{end}}
+	{{define "T3"}}{{template "T1"}} {{template "T2"}}{{end}}
+	{{template "T3"}}`
+
+This defines two templates, T1 and T2, and a third T3 that invokes the other two
+when it is executed. Finally it invokes T3. If executed this template will
+produce the text
+
+	ONE TWO
+
+By construction, a template may reside in only one association. If it's
+necessary to have a template addressable from multiple associations, the
+template definition must be parsed multiple times to create distinct *Template
+values, or must be copied with the Clone or AddParseTree method.
+
+Parse may be called multiple times to assemble the various associated templates;
+see the ParseFiles and ParseGlob functions and methods for simple ways to parse
+related templates stored in files.
+
+A template may be executed directly or through ExecuteTemplate, which executes
+an associated template identified by name. To invoke our example above, we
+might write,
+
+	err := tmpl.Execute(os.Stdout, "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+or to invoke a particular template explicitly by name,
+
+	err := tmpl.ExecuteTemplate(os.Stdout, "T2", "no data needed")
+	if err != nil {
+		log.Fatalf("execution failed: %s", err)
+	}
+
+*/
+package template

vendor/github.com/alecthomas/template/exec.go

@@ -0,0 +1,845 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+	"runtime"
+	"sort"
+	"strings"
+
+	"github.com/alecthomas/template/parse"
+)
+
+// state represents the state of an execution. It's not part of the
+// template so that multiple executions of the same template
+// can execute in parallel.
+type state struct {
+	tmpl *Template
+	wr   io.Writer
+	node parse.Node // current node, for errors
+	vars []variable // push-down stack of variable values.
+}
+
+// variable holds the dynamic value of a variable such as $, $x etc.
+type variable struct {
+	name  string
+	value reflect.Value
+}
+
+// push pushes a new variable on the stack.
+func (s *state) push(name string, value reflect.Value) {
+	s.vars = append(s.vars, variable{name, value})
+}
+
+// mark returns the length of the variable stack.
+func (s *state) mark() int {
+	return len(s.vars)
+}
+
+// pop pops the variable stack up to the mark.
+func (s *state) pop(mark int) {
+	s.vars = s.vars[0:mark]
+}
+
+// setVar overwrites the top-nth variable on the stack. Used by range iterations.
+func (s *state) setVar(n int, value reflect.Value) {
+	s.vars[len(s.vars)-n].value = value
+}
+
+// varValue returns the value of the named variable.
+func (s *state) varValue(name string) reflect.Value {
+	for i := s.mark() - 1; i >= 0; i-- {
+		if s.vars[i].name == name {
+			return s.vars[i].value
+		}
+	}
+	s.errorf("undefined variable: %s", name)
+	return zero
+}
+
+var zero reflect.Value
+
+// at marks the state to be on node n, for error reporting.
+func (s *state) at(node parse.Node) {
+	s.node = node
+}
+
+// doublePercent returns the string with %'s replaced by %%, if necessary,
+// so it can be used safely inside a Printf format string.
+func doublePercent(str string) string {
+	if strings.Contains(str, "%") {
+		str = strings.Replace(str, "%", "%%", -1)
+	}
+	return str
+}
+
+// errorf formats the error and terminates processing.
+func (s *state) errorf(format string, args ...interface{}) {
+	name := doublePercent(s.tmpl.Name())
+	if s.node == nil {
+		format = fmt.Sprintf("template: %s: %s", name, format)
+	} else {
+		location, context := s.tmpl.ErrorContext(s.node)
+		format = fmt.Sprintf("template: %s: executing %q at <%s>: %s", location, name, doublePercent(context), format)
+	}
+	panic(fmt.Errorf(format, args...))
+}
+
+// errRecover is the handler that turns panics into returns from the top
+// level of Parse.
+func errRecover(errp *error) {
+	e := recover()
+	if e != nil {
+		switch err := e.(type) {
+		case runtime.Error:
+			panic(e)
+		case error:
+			*errp = err
+		default:
+			panic(e)
+		}
+	}
+}
+
+// ExecuteTemplate applies the template associated with t that has the given name
+// to the specified data object and writes the output to wr.
+// If an error occurs executing the template or writing its output,
+// execution stops, but partial results may already have been written to
+// the output writer.
+// A template may be executed safely in parallel.
+func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
+	tmpl := t.tmpl[name]
+	if tmpl == nil {
+		return fmt.Errorf("template: no template %q associated with template %q", name, t.name)
+	}
+	return tmpl.Execute(wr, data)
+}
+
+// Execute applies a parsed template to the specified data object,
+// and writes the output to wr.
+// If an error occurs executing the template or writing its output,
+// execution stops, but partial results may already have been written to
+// the output writer.
+// A template may be executed safely in parallel.
+func (t *Template) Execute(wr io.Writer, data interface{}) (err error) {
+	defer errRecover(&err)
+	value := reflect.ValueOf(data)
+	state := &state{
+		tmpl: t,
+		wr:   wr,
+		vars: []variable{{"$", value}},
+	}
+	t.init()
+	if t.Tree == nil || t.Root == nil {
+		var b bytes.Buffer
+		for name, tmpl := range t.tmpl {
+			if tmpl.Tree == nil || tmpl.Root == nil {
+				continue
+			}
+			if b.Len() > 0 {
+				b.WriteString(", ")
+			}
+			fmt.Fprintf(&b, "%q", name)
+		}
+		var s string
+		if b.Len() > 0 {
+			s = "; defined templates are: " + b.String()
+		}
+		state.errorf("%q is an incomplete or empty template%s", t.Name(), s)
+	}
+	state.walk(value, t.Root)
+	return
+}
+
+// Walk functions step through the major pieces of the template structure,
+// generating output as they go.
+func (s *state) walk(dot reflect.Value, node parse.Node) {
+	s.at(node)
+	switch node := node.(type) {
+	case *parse.ActionNode:
+		// Do not pop variables so they persist until next end.
+		// Also, if the action declares variables, don't print the result.
+		val := s.evalPipeline(dot, node.Pipe)
+		if len(node.Pipe.Decl) == 0 {
+			s.printValue(node, val)
+		}
+	case *parse.IfNode:
+		s.walkIfOrWith(parse.NodeIf, dot, node.Pipe, node.List, node.ElseList)
+	case *parse.ListNode:
+		for _, node := range node.Nodes {
+			s.walk(dot, node)
+		}
+	case *parse.RangeNode:
+		s.walkRange(dot, node)
+	case *parse.TemplateNode:
+		s.walkTemplate(dot, node)
+	case *parse.TextNode:
+		if _, err := s.wr.Write(node.Text); err != nil {
+			s.errorf("%s", err)
+		}
+	case *parse.WithNode:
+		s.walkIfOrWith(parse.NodeWith, dot, node.Pipe, node.List, node.ElseList)
+	default:
+		s.errorf("unknown node: %s", node)
+	}
+}
+
+// walkIfOrWith walks an 'if' or 'with' node. The two control structures
+// are identical in behavior except that 'with' sets dot.
+func (s *state) walkIfOrWith(typ parse.NodeType, dot reflect.Value, pipe *parse.PipeNode, list, elseList *parse.ListNode) {
+	defer s.pop(s.mark())
+	val := s.evalPipeline(dot, pipe)
+	truth, ok := isTrue(val)
+	if !ok {
+		s.errorf("if/with can't use %v", val)
+	}
+	if truth {
+		if typ == parse.NodeWith {
+			s.walk(val, list)
+		} else {
+			s.walk(dot, list)
+		}
+	} else if elseList != nil {
+		s.walk(dot, elseList)
+	}
+}
+
+// isTrue reports whether the value is 'true', in the sense of not the zero of its type,
+// and whether the value has a meaningful truth value.
+func isTrue(val reflect.Value) (truth, ok bool) {
+	if !val.IsValid() {
+		// Something like var x interface{}, never set. It's a form of nil.
+		return false, true
+	}
+	switch val.Kind() {
+	case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+		truth = val.Len() > 0
+	case reflect.Bool:
+		truth = val.Bool()
+	case reflect.Complex64, reflect.Complex128:
+		truth = val.Complex() != 0
+	case reflect.Chan, reflect.Func, reflect.Ptr, reflect.Interface:
+		truth = !val.IsNil()
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		truth = val.Int() != 0
+	case reflect.Float32, reflect.Float64:
+		truth = val.Float() != 0
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		truth = val.Uint() != 0
+	case reflect.Struct:
+		truth = true // Struct values are always true.
+	default:
+		return
+	}
+	return truth, true
+}
+
+func (s *state) walkRange(dot reflect.Value, r *parse.RangeNode) {
+	s.at(r)
+	defer s.pop(s.mark())
+	val, _ := indirect(s.evalPipeline(dot, r.Pipe))
+	// mark top of stack before any variables in the body are pushed.
+	mark := s.mark()
+	oneIteration := func(index, elem reflect.Value) {
+		// Set top var (lexically the second if there are two) to the element.
+		if len(r.Pipe.Decl) > 0 {
+			s.setVar(1, elem)
+		}
+		// Set next var (lexically the first if there are two) to the index.
+		if len(r.Pipe.Decl) > 1 {
+			s.setVar(2, index)
+		}
+		s.walk(elem, r.List)
+		s.pop(mark)
+	}
+	switch val.Kind() {
+	case reflect.Array, reflect.Slice:
+		if val.Len() == 0 {
+			break
+		}
+		for i := 0; i < val.Len(); i++ {
+			oneIteration(reflect.ValueOf(i), val.Index(i))
+		}
+		return
+	case reflect.Map:
+		if val.Len() == 0 {
+			break
+		}
+		for _, key := range sortKeys(val.MapKeys()) {
+			oneIteration(key, val.MapIndex(key))
+		}
+		return
+	case reflect.Chan:
+		if val.IsNil() {
+			break
+		}
+		i := 0
+		for ; ; i++ {
+			elem, ok := val.Recv()
+			if !ok {
+				break
+			}
+			oneIteration(reflect.ValueOf(i), elem)
+		}
+		if i == 0 {
+			break
+		}
+		return
+	case reflect.Invalid:
+		break // An invalid value is likely a nil map, etc. and acts like an empty map.
+	default:
+		s.errorf("range can't iterate over %v", val)
+	}
+	if r.ElseList != nil {
+		s.walk(dot, r.ElseList)
+	}
+}
+
+func (s *state) walkTemplate(dot reflect.Value, t *parse.TemplateNode) {
+	s.at(t)
+	tmpl := s.tmpl.tmpl[t.Name]
+	if tmpl == nil {
+		s.errorf("template %q not defined", t.Name)
+	}
+	// Variables declared by the pipeline persist.
+	dot = s.evalPipeline(dot, t.Pipe)
+	newState := *s
+	newState.tmpl = tmpl
+	// No dynamic scoping: template invocations inherit no variables.
+	newState.vars = []variable{{"$", dot}}
+	newState.walk(dot, tmpl.Root)
+}
+
+// Eval functions evaluate pipelines, commands, and their elements and extract
+// values from the data structure by examining fields, calling methods, and so on.
+// The printing of those values happens only through walk functions.
+
+// evalPipeline returns the value acquired by evaluating a pipeline. If the
+// pipeline has a variable declaration, the variable will be pushed on the
+// stack. Callers should therefore pop the stack after they are finished
+// executing commands depending on the pipeline value.
+func (s *state) evalPipeline(dot reflect.Value, pipe *parse.PipeNode) (value reflect.Value) {
+	if pipe == nil {
+		return
+	}
+	s.at(pipe)
+	for _, cmd := range pipe.Cmds {
+		value = s.evalCommand(dot, cmd, value) // previous value is this one's final arg.
+		// If the object has type interface{}, dig down one level to the thing inside.
+		if value.Kind() == reflect.Interface && value.Type().NumMethod() == 0 {
+			value = reflect.ValueOf(value.Interface()) // lovely!
+		}
+	}
+	for _, variable := range pipe.Decl {
+		s.push(variable.Ident[0], value)
+	}
+	return value
+}
+
+func (s *state) notAFunction(args []parse.Node, final reflect.Value) {
+	if len(args) > 1 || final.IsValid() {
+		s.errorf("can't give argument to non-function %s", args[0])
+	}
+}
+
+func (s *state) evalCommand(dot reflect.Value, cmd *parse.CommandNode, final reflect.Value) reflect.Value {
+	firstWord := cmd.Args[0]
+	switch n := firstWord.(type) {
+	case *parse.FieldNode:
+		return s.evalFieldNode(dot, n, cmd.Args, final)
+	case *parse.ChainNode:
+		return s.evalChainNode(dot, n, cmd.Args, final)
+	case *parse.IdentifierNode:
+		// Must be a function.
+		return s.evalFunction(dot, n, cmd, cmd.Args, final)
+	case *parse.PipeNode:
+		// Parenthesized pipeline. The arguments are all inside the pipeline; final is ignored.
+		return s.evalPipeline(dot, n)
+	case *parse.VariableNode:
+		return s.evalVariableNode(dot, n, cmd.Args, final)
+	}
+	s.at(firstWord)
+	s.notAFunction(cmd.Args, final)
+	switch word := firstWord.(type) {
+	case *parse.BoolNode:
+		return reflect.ValueOf(word.True)
+	case *parse.DotNode:
+		return dot
+	case *parse.NilNode:
+		s.errorf("nil is not a command")
+	case *parse.NumberNode:
+		return s.idealConstant(word)
+	case *parse.StringNode:
+		return reflect.ValueOf(word.Text)
+	}
+	s.errorf("can't evaluate command %q", firstWord)
+	panic("not reached")
+}
+
+// idealConstant is called to return the value of a number in a context where
+// we don't know the type. In that case, the syntax of the number tells us
+// its type, and we use Go rules to resolve.  Note there is no such thing as
+// a uint ideal constant in this situation - the value must be of int type.
+func (s *state) idealConstant(constant *parse.NumberNode) reflect.Value {
+	// These are ideal constants but we don't know the type
+	// and we have no context.  (If it was a method argument,
+	// we'd know what we need.) The syntax guides us to some extent.
+	s.at(constant)
+	switch {
+	case constant.IsComplex:
+		return reflect.ValueOf(constant.Complex128) // incontrovertible.
+	case constant.IsFloat && !isHexConstant(constant.Text) && strings.IndexAny(constant.Text, ".eE") >= 0:
+		return reflect.ValueOf(constant.Float64)
+	case constant.IsInt:
+		n := int(constant.Int64)
+		if int64(n) != constant.Int64 {
+			s.errorf("%s overflows int", constant.Text)
+		}
+		return reflect.ValueOf(n)
+	case constant.IsUint:
+		s.errorf("%s overflows int", constant.Text)
+	}
+	return zero
+}
+
+func isHexConstant(s string) bool {
+	return len(s) > 2 && s[0] == '0' && (s[1] == 'x' || s[1] == 'X')
+}
+
+func (s *state) evalFieldNode(dot reflect.Value, field *parse.FieldNode, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(field)
+	return s.evalFieldChain(dot, dot, field, field.Ident, args, final)
+}
+
+func (s *state) evalChainNode(dot reflect.Value, chain *parse.ChainNode, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(chain)
+	// (pipe).Field1.Field2 has pipe as .Node, fields as .Field. Eval the pipeline, then the fields.
+	pipe := s.evalArg(dot, nil, chain.Node)
+	if len(chain.Field) == 0 {
+		s.errorf("internal error: no fields in evalChainNode")
+	}
+	return s.evalFieldChain(dot, pipe, chain, chain.Field, args, final)
+}
+
+func (s *state) evalVariableNode(dot reflect.Value, variable *parse.VariableNode, args []parse.Node, final reflect.Value) reflect.Value {
+	// $x.Field has $x as the first ident, Field as the second. Eval the var, then the fields.
+	s.at(variable)
+	value := s.varValue(variable.Ident[0])
+	if len(variable.Ident) == 1 {
+		s.notAFunction(args, final)
+		return value
+	}
+	return s.evalFieldChain(dot, value, variable, variable.Ident[1:], args, final)
+}
+
+// evalFieldChain evaluates .X.Y.Z possibly followed by arguments.
+// dot is the environment in which to evaluate arguments, while
+// receiver is the value being walked along the chain.
+func (s *state) evalFieldChain(dot, receiver reflect.Value, node parse.Node, ident []string, args []parse.Node, final reflect.Value) reflect.Value {
+	n := len(ident)
+	for i := 0; i < n-1; i++ {
+		receiver = s.evalField(dot, ident[i], node, nil, zero, receiver)
+	}
+	// Now if it's a method, it gets the arguments.
+	return s.evalField(dot, ident[n-1], node, args, final, receiver)
+}
+
+func (s *state) evalFunction(dot reflect.Value, node *parse.IdentifierNode, cmd parse.Node, args []parse.Node, final reflect.Value) reflect.Value {
+	s.at(node)
+	name := node.Ident
+	function, ok := findFunction(name, s.tmpl)
+	if !ok {
+		s.errorf("%q is not a defined function", name)
+	}
+	return s.evalCall(dot, function, cmd, name, args, final)
+}
+
+// evalField evaluates an expression like (.Field) or (.Field arg1 arg2).
+// The 'final' argument represents the return value from the preceding
+// value of the pipeline, if any.
+func (s *state) evalField(dot reflect.Value, fieldName string, node parse.Node, args []parse.Node, final, receiver reflect.Value) reflect.Value {
+	if !receiver.IsValid() {
+		return zero
+	}
+	typ := receiver.Type()
+	receiver, _ = indirect(receiver)
+	// Unless it's an interface, need to get to a value of type *T to guarantee
+	// we see all methods of T and *T.
+	ptr := receiver
+	if ptr.Kind() != reflect.Interface && ptr.CanAddr() {
+		ptr = ptr.Addr()
+	}
+	if method := ptr.MethodByName(fieldName); method.IsValid() {
+		return s.evalCall(dot, method, node, fieldName, args, final)
+	}
+	hasArgs := len(args) > 1 || final.IsValid()
+	// It's not a method; must be a field of a struct or an element of a map. The receiver must not be nil.
+	receiver, isNil := indirect(receiver)
+	if isNil {
+		s.errorf("nil pointer evaluating %s.%s", typ, fieldName)
+	}
+	switch receiver.Kind() {
+	case reflect.Struct:
+		tField, ok := receiver.Type().FieldByName(fieldName)
+		if ok {
+			field := receiver.FieldByIndex(tField.Index)
+			if tField.PkgPath != "" { // field is unexported
+				s.errorf("%s is an unexported field of struct type %s", fieldName, typ)
+			}
+			// If it's a function, we must call it.
+			if hasArgs {
+				s.errorf("%s has arguments but cannot be invoked as function", fieldName)
+			}
+			return field
+		}
+		s.errorf("%s is not a field of struct type %s", fieldName, typ)
+	case reflect.Map:
+		// If it's a map, attempt to use the field name as a key.
+		nameVal := reflect.ValueOf(fieldName)
+		if nameVal.Type().AssignableTo(receiver.Type().Key()) {
+			if hasArgs {
+				s.errorf("%s is not a method but has arguments", fieldName)
+			}
+			return receiver.MapIndex(nameVal)
+		}
+	}
+	s.errorf("can't evaluate field %s in type %s", fieldName, typ)
+	panic("not reached")
+}
+
+var (
+	errorType       = reflect.TypeOf((*error)(nil)).Elem()
+	fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
+)
+
+// evalCall executes a function or method call. If it's a method, fun already has the receiver bound, so
+// it looks just like a function call.  The arg list, if non-nil, includes (in the manner of the shell), arg[0]
+// as the function itself.
+func (s *state) evalCall(dot, fun reflect.Value, node parse.Node, name string, args []parse.Node, final reflect.Value) reflect.Value {
+	if args != nil {
+		args = args[1:] // Zeroth arg is function name/node; not passed to function.
+	}
+	typ := fun.Type()
+	numIn := len(args)
+	if final.IsValid() {
+		numIn++
+	}
+	numFixed := len(args)
+	if typ.IsVariadic() {
+		numFixed = typ.NumIn() - 1 // last arg is the variadic one.
+		if numIn < numFixed {
+			s.errorf("wrong number of args for %s: want at least %d got %d", name, typ.NumIn()-1, len(args))
+		}
+	} else if numIn < typ.NumIn()-1 || !typ.IsVariadic() && numIn != typ.NumIn() {
+		s.errorf("wrong number of args for %s: want %d got %d", name, typ.NumIn(), len(args))
+	}
+	if !goodFunc(typ) {
+		// TODO: This could still be a confusing error; maybe goodFunc should provide info.
+		s.errorf("can't call method/function %q with %d results", name, typ.NumOut())
+	}
+	// Build the arg list.
+	argv := make([]reflect.Value, numIn)
+	// Args must be evaluated. Fixed args first.
+	i := 0
+	for ; i < numFixed && i < len(args); i++ {
+		argv[i] = s.evalArg(dot, typ.In(i), args[i])
+	}
+	// Now the ... args.
+	if typ.IsVariadic() {
+		argType := typ.In(typ.NumIn() - 1).Elem() // Argument is a slice.
+		for ; i < len(args); i++ {
+			argv[i] = s.evalArg(dot, argType, args[i])
+		}
+	}
+	// Add final value if necessary.
+	if final.IsValid() {
+		t := typ.In(typ.NumIn() - 1)
+		if typ.IsVariadic() {
+			t = t.Elem()
+		}
+		argv[i] = s.validateType(final, t)
+	}
+	result := fun.Call(argv)
+	// If we have an error that is not nil, stop execution and return that error to the caller.
+	if len(result) == 2 && !result[1].IsNil() {
+		s.at(node)
+		s.errorf("error calling %s: %s", name, result[1].Interface().(error))
+	}
+	return result[0]
+}
+
+// canBeNil reports whether an untyped nil can be assigned to the type. See reflect.Zero.
+func canBeNil(typ reflect.Type) bool {
+	switch typ.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return true
+	}
+	return false
+}
+
+// validateType guarantees that the value is valid and assignable to the type.
+func (s *state) validateType(value reflect.Value, typ reflect.Type) reflect.Value {
+	if !value.IsValid() {
+		if typ == nil || canBeNil(typ) {
+			// An untyped nil interface{}. Accept as a proper nil value.
+			return reflect.Zero(typ)
+		}
+		s.errorf("invalid value; expected %s", typ)
+	}
+	if typ != nil && !value.Type().AssignableTo(typ) {
+		if value.Kind() == reflect.Interface && !value.IsNil() {
+			value = value.Elem()
+			if value.Type().AssignableTo(typ) {
+				return value
+			}
+			// fallthrough
+		}
+		// Does one dereference or indirection work? We could do more, as we
+		// do with method receivers, but that gets messy and method receivers
+		// are much more constrained, so it makes more sense there than here.
+		// Besides, one is almost always all you need.
+		switch {
+		case value.Kind() == reflect.Ptr && value.Type().Elem().AssignableTo(typ):
+			value = value.Elem()
+			if !value.IsValid() {
+				s.errorf("dereference of nil pointer of type %s", typ)
+			}
+		case reflect.PtrTo(value.Type()).AssignableTo(typ) && value.CanAddr():
+			value = value.Addr()
+		default:
+			s.errorf("wrong type for value; expected %s; got %s", typ, value.Type())
+		}
+	}
+	return value
+}
+
+func (s *state) evalArg(dot reflect.Value, typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	switch arg := n.(type) {
+	case *parse.DotNode:
+		return s.validateType(dot, typ)
+	case *parse.NilNode:
+		if canBeNil(typ) {
+			return reflect.Zero(typ)
+		}
+		s.errorf("cannot assign nil to %s", typ)
+	case *parse.FieldNode:
+		return s.validateType(s.evalFieldNode(dot, arg, []parse.Node{n}, zero), typ)
+	case *parse.VariableNode:
+		return s.validateType(s.evalVariableNode(dot, arg, nil, zero), typ)
+	case *parse.PipeNode:
+		return s.validateType(s.evalPipeline(dot, arg), typ)
+	case *parse.IdentifierNode:
+		return s.evalFunction(dot, arg, arg, nil, zero)
+	case *parse.ChainNode:
+		return s.validateType(s.evalChainNode(dot, arg, nil, zero), typ)
+	}
+	switch typ.Kind() {
+	case reflect.Bool:
+		return s.evalBool(typ, n)
+	case reflect.Complex64, reflect.Complex128:
+		return s.evalComplex(typ, n)
+	case reflect.Float32, reflect.Float64:
+		return s.evalFloat(typ, n)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return s.evalInteger(typ, n)
+	case reflect.Interface:
+		if typ.NumMethod() == 0 {
+			return s.evalEmptyInterface(dot, n)
+		}
+	case reflect.String:
+		return s.evalString(typ, n)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return s.evalUnsignedInteger(typ, n)
+	}
+	s.errorf("can't handle %s for arg of type %s", n, typ)
+	panic("not reached")
+}
+
+func (s *state) evalBool(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.BoolNode); ok {
+		value := reflect.New(typ).Elem()
+		value.SetBool(n.True)
+		return value
+	}
+	s.errorf("expected bool; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalString(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.StringNode); ok {
+		value := reflect.New(typ).Elem()
+		value.SetString(n.Text)
+		return value
+	}
+	s.errorf("expected string; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalInteger(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsInt {
+		value := reflect.New(typ).Elem()
+		value.SetInt(n.Int64)
+		return value
+	}
+	s.errorf("expected integer; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalUnsignedInteger(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsUint {
+		value := reflect.New(typ).Elem()
+		value.SetUint(n.Uint64)
+		return value
+	}
+	s.errorf("expected unsigned integer; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalFloat(typ reflect.Type, n parse.Node) reflect.Value {
+	s.at(n)
+	if n, ok := n.(*parse.NumberNode); ok && n.IsFloat {
+		value := reflect.New(typ).Elem()
+		value.SetFloat(n.Float64)
+		return value
+	}
+	s.errorf("expected float; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalComplex(typ reflect.Type, n parse.Node) reflect.Value {
+	if n, ok := n.(*parse.NumberNode); ok && n.IsComplex {
+		value := reflect.New(typ).Elem()
+		value.SetComplex(n.Complex128)
+		return value
+	}
+	s.errorf("expected complex; found %s", n)
+	panic("not reached")
+}
+
+func (s *state) evalEmptyInterface(dot reflect.Value, n parse.Node) reflect.Value {
+	s.at(n)
+	switch n := n.(type) {
+	case *parse.BoolNode:
+		return reflect.ValueOf(n.True)
+	case *parse.DotNode:
+		return dot
+	case *parse.FieldNode:
+		return s.evalFieldNode(dot, n, nil, zero)
+	case *parse.IdentifierNode:
+		return s.evalFunction(dot, n, n, nil, zero)
+	case *parse.NilNode:
+		// NilNode is handled in evalArg, the only place that calls here.
+		s.errorf("evalEmptyInterface: nil (can't happen)")
+	case *parse.NumberNode:
+		return s.idealConstant(n)
+	case *parse.StringNode:
+		return reflect.ValueOf(n.Text)
+	case *parse.VariableNode:
+		return s.evalVariableNode(dot, n, nil, zero)
+	case *parse.PipeNode:
+		return s.evalPipeline(dot, n)
+	}
+	s.errorf("can't handle assignment of %s to empty interface argument", n)
+	panic("not reached")
+}
+
+// indirect returns the item at the end of indirection, and a bool to indicate if it's nil.
+// We indirect through pointers and empty interfaces (only) because
+// non-empty interfaces have methods we might need.
+func indirect(v reflect.Value) (rv reflect.Value, isNil bool) {
+	for ; v.Kind() == reflect.Ptr || v.Kind() == reflect.Interface; v = v.Elem() {
+		if v.IsNil() {
+			return v, true
+		}
+		if v.Kind() == reflect.Interface && v.NumMethod() > 0 {
+			break
+		}
+	}
+	return v, false
+}
+
+// printValue writes the textual representation of the value to the output of
+// the template.
+func (s *state) printValue(n parse.Node, v reflect.Value) {
+	s.at(n)
+	iface, ok := printableValue(v)
+	if !ok {
+		s.errorf("can't print %s of type %s", n, v.Type())
+	}
+	fmt.Fprint(s.wr, iface)
+}
+
+// printableValue returns the, possibly indirected, interface value inside v that
+// is best for a call to formatted printer.
+func printableValue(v reflect.Value) (interface{}, bool) {
+	if v.Kind() == reflect.Ptr {
+		v, _ = indirect(v) // fmt.Fprint handles nil.
+	}
+	if !v.IsValid() {
+		return "<no value>", true
+	}
+
+	if !v.Type().Implements(errorType) && !v.Type().Implements(fmtStringerType) {
+		if v.CanAddr() && (reflect.PtrTo(v.Type()).Implements(errorType) || reflect.PtrTo(v.Type()).Implements(fmtStringerType)) {
+			v = v.Addr()
+		} else {
+			switch v.Kind() {
+			case reflect.Chan, reflect.Func:
+				return nil, false
+			}
+		}
+	}
+	return v.Interface(), true
+}
+
+// Types to help sort the keys in a map for reproducible output.
+
+type rvs []reflect.Value
+
+func (x rvs) Len() int      { return len(x) }
+func (x rvs) Swap(i, j int) { x[i], x[j] = x[j], x[i] }
+
+type rvInts struct{ rvs }
+
+func (x rvInts) Less(i, j int) bool { return x.rvs[i].Int() < x.rvs[j].Int() }
+
+type rvUints struct{ rvs }
+
+func (x rvUints) Less(i, j int) bool { return x.rvs[i].Uint() < x.rvs[j].Uint() }
+
+type rvFloats struct{ rvs }
+
+func (x rvFloats) Less(i, j int) bool { return x.rvs[i].Float() < x.rvs[j].Float() }
+
+type rvStrings struct{ rvs }
+
+func (x rvStrings) Less(i, j int) bool { return x.rvs[i].String() < x.rvs[j].String() }
+
+// sortKeys sorts (if it can) the slice of reflect.Values, which is a slice of map keys.
+func sortKeys(v []reflect.Value) []reflect.Value {
+	if len(v) <= 1 {
+		return v
+	}
+	switch v[0].Kind() {
+	case reflect.Float32, reflect.Float64:
+		sort.Sort(rvFloats{v})
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		sort.Sort(rvInts{v})
+	case reflect.String:
+		sort.Sort(rvStrings{v})
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		sort.Sort(rvUints{v})
+	}
+	return v
+}

vendor/github.com/alecthomas/template/funcs.go

@@ -0,0 +1,598 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"reflect"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// FuncMap is the type of the map defining the mapping from names to functions.
+// Each function must have either a single return value, or two return values of
+// which the second has type error. In that case, if the second (error)
+// return value evaluates to non-nil during execution, execution terminates and
+// Execute returns that error.
+type FuncMap map[string]interface{}
+
+var builtins = FuncMap{
+	"and":      and,
+	"call":     call,
+	"html":     HTMLEscaper,
+	"index":    index,
+	"js":       JSEscaper,
+	"len":      length,
+	"not":      not,
+	"or":       or,
+	"print":    fmt.Sprint,
+	"printf":   fmt.Sprintf,
+	"println":  fmt.Sprintln,
+	"urlquery": URLQueryEscaper,
+
+	// Comparisons
+	"eq": eq, // ==
+	"ge": ge, // >=
+	"gt": gt, // >
+	"le": le, // <=
+	"lt": lt, // <
+	"ne": ne, // !=
+}
+
+var builtinFuncs = createValueFuncs(builtins)
+
+// createValueFuncs turns a FuncMap into a map[string]reflect.Value
+func createValueFuncs(funcMap FuncMap) map[string]reflect.Value {
+	m := make(map[string]reflect.Value)
+	addValueFuncs(m, funcMap)
+	return m
+}
+
+// addValueFuncs adds to values the functions in funcs, converting them to reflect.Values.
+func addValueFuncs(out map[string]reflect.Value, in FuncMap) {
+	for name, fn := range in {
+		v := reflect.ValueOf(fn)
+		if v.Kind() != reflect.Func {
+			panic("value for " + name + " not a function")
+		}
+		if !goodFunc(v.Type()) {
+			panic(fmt.Errorf("can't install method/function %q with %d results", name, v.Type().NumOut()))
+		}
+		out[name] = v
+	}
+}
+
+// addFuncs adds to values the functions in funcs. It does no checking of the input -
+// call addValueFuncs first.
+func addFuncs(out, in FuncMap) {
+	for name, fn := range in {
+		out[name] = fn
+	}
+}
+
+// goodFunc checks that the function or method has the right result signature.
+func goodFunc(typ reflect.Type) bool {
+	// We allow functions with 1 result or 2 results where the second is an error.
+	switch {
+	case typ.NumOut() == 1:
+		return true
+	case typ.NumOut() == 2 && typ.Out(1) == errorType:
+		return true
+	}
+	return false
+}
+
+// findFunction looks for a function in the template, and global map.
+func findFunction(name string, tmpl *Template) (reflect.Value, bool) {
+	if tmpl != nil && tmpl.common != nil {
+		if fn := tmpl.execFuncs[name]; fn.IsValid() {
+			return fn, true
+		}
+	}
+	if fn := builtinFuncs[name]; fn.IsValid() {
+		return fn, true
+	}
+	return reflect.Value{}, false
+}
+
+// Indexing.
+
+// index returns the result of indexing its first argument by the following
+// arguments.  Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
+// indexed item must be a map, slice, or array.
+func index(item interface{}, indices ...interface{}) (interface{}, error) {
+	v := reflect.ValueOf(item)
+	for _, i := range indices {
+		index := reflect.ValueOf(i)
+		var isNil bool
+		if v, isNil = indirect(v); isNil {
+			return nil, fmt.Errorf("index of nil pointer")
+		}
+		switch v.Kind() {
+		case reflect.Array, reflect.Slice, reflect.String:
+			var x int64
+			switch index.Kind() {
+			case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+				x = index.Int()
+			case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+				x = int64(index.Uint())
+			default:
+				return nil, fmt.Errorf("cannot index slice/array with type %s", index.Type())
+			}
+			if x < 0 || x >= int64(v.Len()) {
+				return nil, fmt.Errorf("index out of range: %d", x)
+			}
+			v = v.Index(int(x))
+		case reflect.Map:
+			if !index.IsValid() {
+				index = reflect.Zero(v.Type().Key())
+			}
+			if !index.Type().AssignableTo(v.Type().Key()) {
+				return nil, fmt.Errorf("%s is not index type for %s", index.Type(), v.Type())
+			}
+			if x := v.MapIndex(index); x.IsValid() {
+				v = x
+			} else {
+				v = reflect.Zero(v.Type().Elem())
+			}
+		default:
+			return nil, fmt.Errorf("can't index item of type %s", v.Type())
+		}
+	}
+	return v.Interface(), nil
+}
+
+// Length
+
+// length returns the length of the item, with an error if it has no defined length.
+func length(item interface{}) (int, error) {
+	v, isNil := indirect(reflect.ValueOf(item))
+	if isNil {
+		return 0, fmt.Errorf("len of nil pointer")
+	}
+	switch v.Kind() {
+	case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
+		return v.Len(), nil
+	}
+	return 0, fmt.Errorf("len of type %s", v.Type())
+}
+
+// Function invocation
+
+// call returns the result of evaluating the first argument as a function.
+// The function must return 1 result, or 2 results, the second of which is an error.
+func call(fn interface{}, args ...interface{}) (interface{}, error) {
+	v := reflect.ValueOf(fn)
+	typ := v.Type()
+	if typ.Kind() != reflect.Func {
+		return nil, fmt.Errorf("non-function of type %s", typ)
+	}
+	if !goodFunc(typ) {
+		return nil, fmt.Errorf("function called with %d args; should be 1 or 2", typ.NumOut())
+	}
+	numIn := typ.NumIn()
+	var dddType reflect.Type
+	if typ.IsVariadic() {
+		if len(args) < numIn-1 {
+			return nil, fmt.Errorf("wrong number of args: got %d want at least %d", len(args), numIn-1)
+		}
+		dddType = typ.In(numIn - 1).Elem()
+	} else {
+		if len(args) != numIn {
+			return nil, fmt.Errorf("wrong number of args: got %d want %d", len(args), numIn)
+		}
+	}
+	argv := make([]reflect.Value, len(args))
+	for i, arg := range args {
+		value := reflect.ValueOf(arg)
+		// Compute the expected type. Clumsy because of variadics.
+		var argType reflect.Type
+		if !typ.IsVariadic() || i < numIn-1 {
+			argType = typ.In(i)
+		} else {
+			argType = dddType
+		}
+		if !value.IsValid() && canBeNil(argType) {
+			value = reflect.Zero(argType)
+		}
+		if !value.Type().AssignableTo(argType) {
+			return nil, fmt.Errorf("arg %d has type %s; should be %s", i, value.Type(), argType)
+		}
+		argv[i] = value
+	}
+	result := v.Call(argv)
+	if len(result) == 2 && !result[1].IsNil() {
+		return result[0].Interface(), result[1].Interface().(error)
+	}
+	return result[0].Interface(), nil
+}
+
+// Boolean logic.
+
+func truth(a interface{}) bool {
+	t, _ := isTrue(reflect.ValueOf(a))
+	return t
+}
+
+// and computes the Boolean AND of its arguments, returning
+// the first false argument it encounters, or the last argument.
+func and(arg0 interface{}, args ...interface{}) interface{} {
+	if !truth(arg0) {
+		return arg0
+	}
+	for i := range args {
+		arg0 = args[i]
+		if !truth(arg0) {
+			break
+		}
+	}
+	return arg0
+}
+
+// or computes the Boolean OR of its arguments, returning
+// the first true argument it encounters, or the last argument.
+func or(arg0 interface{}, args ...interface{}) interface{} {
+	if truth(arg0) {
+		return arg0
+	}
+	for i := range args {
+		arg0 = args[i]
+		if truth(arg0) {
+			break
+		}
+	}
+	return arg0
+}
+
+// not returns the Boolean negation of its argument.
+func not(arg interface{}) (truth bool) {
+	truth, _ = isTrue(reflect.ValueOf(arg))
+	return !truth
+}
+
+// Comparison.
+
+// TODO: Perhaps allow comparison between signed and unsigned integers.
+
+var (
+	errBadComparisonType = errors.New("invalid type for comparison")
+	errBadComparison     = errors.New("incompatible types for comparison")
+	errNoComparison      = errors.New("missing argument for comparison")
+)
+
+type kind int
+
+const (
+	invalidKind kind = iota
+	boolKind
+	complexKind
+	intKind
+	floatKind
+	integerKind
+	stringKind
+	uintKind
+)
+
+func basicKind(v reflect.Value) (kind, error) {
+	switch v.Kind() {
+	case reflect.Bool:
+		return boolKind, nil
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return intKind, nil
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		return uintKind, nil
+	case reflect.Float32, reflect.Float64:
+		return floatKind, nil
+	case reflect.Complex64, reflect.Complex128:
+		return complexKind, nil
+	case reflect.String:
+		return stringKind, nil
+	}
+	return invalidKind, errBadComparisonType
+}
+
+// eq evaluates the comparison a == b || a == c || ...
+func eq(arg1 interface{}, arg2 ...interface{}) (bool, error) {
+	v1 := reflect.ValueOf(arg1)
+	k1, err := basicKind(v1)
+	if err != nil {
+		return false, err
+	}
+	if len(arg2) == 0 {
+		return false, errNoComparison
+	}
+	for _, arg := range arg2 {
+		v2 := reflect.ValueOf(arg)
+		k2, err := basicKind(v2)
+		if err != nil {
+			return false, err
+		}
+		truth := false
+		if k1 != k2 {
+			// Special case: Can compare integer values regardless of type's sign.
+			switch {
+			case k1 == intKind && k2 == uintKind:
+				truth = v1.Int() >= 0 && uint64(v1.Int()) == v2.Uint()
+			case k1 == uintKind && k2 == intKind:
+				truth = v2.Int() >= 0 && v1.Uint() == uint64(v2.Int())
+			default:
+				return false, errBadComparison
+			}
+		} else {
+			switch k1 {
+			case boolKind:
+				truth = v1.Bool() == v2.Bool()
+			case complexKind:
+				truth = v1.Complex() == v2.Complex()
+			case floatKind:
+				truth = v1.Float() == v2.Float()
+			case intKind:
+				truth = v1.Int() == v2.Int()
+			case stringKind:
+				truth = v1.String() == v2.String()
+			case uintKind:
+				truth = v1.Uint() == v2.Uint()
+			default:
+				panic("invalid kind")
+			}
+		}
+		if truth {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// ne evaluates the comparison a != b.
+func ne(arg1, arg2 interface{}) (bool, error) {
+	// != is the inverse of ==.
+	equal, err := eq(arg1, arg2)
+	return !equal, err
+}
+
+// lt evaluates the comparison a < b.
+func lt(arg1, arg2 interface{}) (bool, error) {
+	v1 := reflect.ValueOf(arg1)
+	k1, err := basicKind(v1)
+	if err != nil {
+		return false, err
+	}
+	v2 := reflect.ValueOf(arg2)
+	k2, err := basicKind(v2)
+	if err != nil {
+		return false, err
+	}
+	truth := false
+	if k1 != k2 {
+		// Special case: Can compare integer values regardless of type's sign.
+		switch {
+		case k1 == intKind && k2 == uintKind:
+			truth = v1.Int() < 0 || uint64(v1.Int()) < v2.Uint()
+		case k1 == uintKind && k2 == intKind:
+			truth = v2.Int() >= 0 && v1.Uint() < uint64(v2.Int())
+		default:
+			return false, errBadComparison
+		}
+	} else {
+		switch k1 {
+		case boolKind, complexKind:
+			return false, errBadComparisonType
+		case floatKind:
+			truth = v1.Float() < v2.Float()
+		case intKind:
+			truth = v1.Int() < v2.Int()
+		case stringKind:
+			truth = v1.String() < v2.String()
+		case uintKind:
+			truth = v1.Uint() < v2.Uint()
+		default:
+			panic("invalid kind")
+		}
+	}
+	return truth, nil
+}
+
+// le evaluates the comparison <= b.
+func le(arg1, arg2 interface{}) (bool, error) {
+	// <= is < or ==.
+	lessThan, err := lt(arg1, arg2)
+	if lessThan || err != nil {
+		return lessThan, err
+	}
+	return eq(arg1, arg2)
+}
+
+// gt evaluates the comparison a > b.
+func gt(arg1, arg2 interface{}) (bool, error) {
+	// > is the inverse of <=.
+	lessOrEqual, err := le(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessOrEqual, nil
+}
+
+// ge evaluates the comparison a >= b.
+func ge(arg1, arg2 interface{}) (bool, error) {
+	// >= is the inverse of <.
+	lessThan, err := lt(arg1, arg2)
+	if err != nil {
+		return false, err
+	}
+	return !lessThan, nil
+}
+
+// HTML escaping.
+
+var (
+	htmlQuot = []byte("&#34;") // shorter than "&quot;"
+	htmlApos = []byte("&#39;") // shorter than "&apos;" and apos was not in HTML until HTML5
+	htmlAmp  = []byte("&amp;")
+	htmlLt   = []byte("&lt;")
+	htmlGt   = []byte("&gt;")
+)
+
+// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
+func HTMLEscape(w io.Writer, b []byte) {
+	last := 0
+	for i, c := range b {
+		var html []byte
+		switch c {
+		case '"':
+			html = htmlQuot
+		case '\'':
+			html = htmlApos
+		case '&':
+			html = htmlAmp
+		case '<':
+			html = htmlLt
+		case '>':
+			html = htmlGt
+		default:
+			continue
+		}
+		w.Write(b[last:i])
+		w.Write(html)
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
+func HTMLEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if strings.IndexAny(s, `'"&<>`) < 0 {
+		return s
+	}
+	var b bytes.Buffer
+	HTMLEscape(&b, []byte(s))
+	return b.String()
+}
+
+// HTMLEscaper returns the escaped HTML equivalent of the textual
+// representation of its arguments.
+func HTMLEscaper(args ...interface{}) string {
+	return HTMLEscapeString(evalArgs(args))
+}
+
+// JavaScript escaping.
+
+var (
+	jsLowUni = []byte(`\u00`)
+	hex      = []byte("0123456789ABCDEF")
+
+	jsBackslash = []byte(`\\`)
+	jsApos      = []byte(`\'`)
+	jsQuot      = []byte(`\"`)
+	jsLt        = []byte(`\x3C`)
+	jsGt        = []byte(`\x3E`)
+)
+
+// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
+func JSEscape(w io.Writer, b []byte) {
+	last := 0
+	for i := 0; i < len(b); i++ {
+		c := b[i]
+
+		if !jsIsSpecial(rune(c)) {
+			// fast path: nothing to do
+			continue
+		}
+		w.Write(b[last:i])
+
+		if c < utf8.RuneSelf {
+			// Quotes, slashes and angle brackets get quoted.
+			// Control characters get written as \u00XX.
+			switch c {
+			case '\\':
+				w.Write(jsBackslash)
+			case '\'':
+				w.Write(jsApos)
+			case '"':
+				w.Write(jsQuot)
+			case '<':
+				w.Write(jsLt)
+			case '>':
+				w.Write(jsGt)
+			default:
+				w.Write(jsLowUni)
+				t, b := c>>4, c&0x0f
+				w.Write(hex[t : t+1])
+				w.Write(hex[b : b+1])
+			}
+		} else {
+			// Unicode rune.
+			r, size := utf8.DecodeRune(b[i:])
+			if unicode.IsPrint(r) {
+				w.Write(b[i : i+size])
+			} else {
+				fmt.Fprintf(w, "\\u%04X", r)
+			}
+			i += size - 1
+		}
+		last = i + 1
+	}
+	w.Write(b[last:])
+}
+
+// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s.
+func JSEscapeString(s string) string {
+	// Avoid allocation if we can.
+	if strings.IndexFunc(s, jsIsSpecial) < 0 {
+		return s
+	}
+	var b bytes.Buffer
+	JSEscape(&b, []byte(s))
+	return b.String()
+}
+
+func jsIsSpecial(r rune) bool {
+	switch r {
+	case '\\', '\'', '"', '<', '>':
+		return true
+	}
+	return r < ' ' || utf8.RuneSelf <= r
+}
+
+// JSEscaper returns the escaped JavaScript equivalent of the textual
+// representation of its arguments.
+func JSEscaper(args ...interface{}) string {
+	return JSEscapeString(evalArgs(args))
+}
+
+// URLQueryEscaper returns the escaped value of the textual representation of
+// its arguments in a form suitable for embedding in a URL query.
+func URLQueryEscaper(args ...interface{}) string {
+	return url.QueryEscape(evalArgs(args))
+}
+
+// evalArgs formats the list of arguments into a string. It is therefore equivalent to
+//	fmt.Sprint(args...)
+// except that each argument is indirected (if a pointer), as required,
+// using the same rules as the default string evaluation during template
+// execution.
+func evalArgs(args []interface{}) string {
+	ok := false
+	var s string
+	// Fast path for simple common case.
+	if len(args) == 1 {
+		s, ok = args[0].(string)
+	}
+	if !ok {
+		for i, arg := range args {
+			a, ok := printableValue(reflect.ValueOf(arg))
+			if ok {
+				args[i] = a
+			} // else left fmt do its thing
+		}
+		s = fmt.Sprint(args...)
+	}
+	return s
+}

vendor/github.com/alecthomas/template/helper.go

@@ -0,0 +1,108 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Helper functions to make constructing templates easier.
+
+package template
+
+import (
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+)
+
+// Functions and methods to parse templates.
+
+// Must is a helper that wraps a call to a function returning (*Template, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//	var t = template.Must(template.New("name").Parse("text"))
+func Must(t *Template, err error) *Template {
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+// ParseFiles creates a new Template and parses the template definitions from
+// the named files. The returned template's name will have the (base) name and
+// (parsed) contents of the first file. There must be at least one file.
+// If an error occurs, parsing stops and the returned *Template is nil.
+func ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(nil, filenames...)
+}
+
+// ParseFiles parses the named files and associates the resulting templates with
+// t. If an error occurs, parsing stops and the returned template is nil;
+// otherwise it is t. There must be at least one file.
+func (t *Template) ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(t, filenames...)
+}
+
+// parseFiles is the helper for the method and function. If the argument
+// template is nil, it is created from the first file.
+func parseFiles(t *Template, filenames ...string) (*Template, error) {
+	if len(filenames) == 0 {
+		// Not really a problem, but be consistent.
+		return nil, fmt.Errorf("template: no files named in call to ParseFiles")
+	}
+	for _, filename := range filenames {
+		b, err := ioutil.ReadFile(filename)
+		if err != nil {
+			return nil, err
+		}
+		s := string(b)
+		name := filepath.Base(filename)
+		// First template becomes return value if not already defined,
+		// and we use that one for subsequent New calls to associate
+		// all the templates together. Also, if this file has the same name
+		// as t, this file becomes the contents of t, so
+		//  t, err := New(name).Funcs(xxx).ParseFiles(name)
+		// works. Otherwise we create a new template associated with t.
+		var tmpl *Template
+		if t == nil {
+			t = New(name)
+		}
+		if name == t.Name() {
+			tmpl = t
+		} else {
+			tmpl = t.New(name)
+		}
+		_, err = tmpl.Parse(s)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return t, nil
+}
+
+// ParseGlob creates a new Template and parses the template definitions from the
+// files identified by the pattern, which must match at least one file. The
+// returned template will have the (base) name and (parsed) contents of the
+// first file matched by the pattern. ParseGlob is equivalent to calling
+// ParseFiles with the list of files matched by the pattern.
+func ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(nil, pattern)
+}
+
+// ParseGlob parses the template definitions in the files identified by the
+// pattern and associates the resulting templates with t. The pattern is
+// processed by filepath.Glob and must match at least one file. ParseGlob is
+// equivalent to calling t.ParseFiles with the list of files matched by the
+// pattern.
+func (t *Template) ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(t, pattern)
+}
+
+// parseGlob is the implementation of the function and method ParseGlob.
+func parseGlob(t *Template, pattern string) (*Template, error) {
+	filenames, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, err
+	}
+	if len(filenames) == 0 {
+		return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+	}
+	return parseFiles(t, filenames...)
+}

vendor/github.com/alecthomas/template/parse/lex.go

@@ -0,0 +1,556 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package parse
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// item represents a token or text string returned from the scanner.
+type item struct {
+	typ itemType // The type of this item.
+	pos Pos      // The starting position, in bytes, of this item in the input string.
+	val string   // The value of this item.
+}
+
+func (i item) String() string {
+	switch {
+	case i.typ == itemEOF:
+		return "EOF"
+	case i.typ == itemError:
+		return i.val
+	case i.typ > itemKeyword:
+		return fmt.Sprintf("<%s>", i.val)
+	case len(i.val) > 10:
+		return fmt.Sprintf("%.10q...", i.val)
+	}
+	return fmt.Sprintf("%q", i.val)
+}
+
+// itemType identifies the type of lex items.
+type itemType int
+
+const (
+	itemError        itemType = iota // error occurred; value is text of error
+	itemBool                         // boolean constant
+	itemChar                         // printable ASCII character; grab bag for comma etc.
+	itemCharConstant                 // character constant
+	itemComplex                      // complex constant (1+2i); imaginary is just a number
+	itemColonEquals                  // colon-equals (':=') introducing a declaration
+	itemEOF
+	itemField        // alphanumeric identifier starting with '.'
+	itemIdentifier   // alphanumeric identifier not starting with '.'
+	itemLeftDelim    // left action delimiter
+	itemLeftParen    // '(' inside action
+	itemNumber       // simple number, including imaginary
+	itemPipe         // pipe symbol
+	itemRawString    // raw quoted string (includes quotes)
+	itemRightDelim   // right action delimiter
+	itemElideNewline // elide newline after right delim
+	itemRightParen   // ')' inside action
+	itemSpace        // run of spaces separating arguments
+	itemString       // quoted string (includes quotes)
+	itemText         // plain text
+	itemVariable     // variable starting with '$', such as '$' or  '$1' or '$hello'
+	// Keywords appear after all the rest.
+	itemKeyword  // used only to delimit the keywords
+	itemDot      // the cursor, spelled '.'
+	itemDefine   // define keyword
+	itemElse     // else keyword
+	itemEnd      // end keyword
+	itemIf       // if keyword
+	itemNil      // the untyped nil constant, easiest to treat as a keyword
+	itemRange    // range keyword
+	itemTemplate // template keyword
+	itemWith     // with keyword
+)
+
+var key = map[string]itemType{
+	".":        itemDot,
+	"define":   itemDefine,
+	"else":     itemElse,
+	"end":      itemEnd,
+	"if":       itemIf,
+	"range":    itemRange,
+	"nil":      itemNil,
+	"template": itemTemplate,
+	"with":     itemWith,
+}
+
+const eof = -1
+
+// stateFn represents the state of the scanner as a function that returns the next state.
+type stateFn func(*lexer) stateFn
+
+// lexer holds the state of the scanner.
+type lexer struct {
+	name       string    // the name of the input; used only for error reports
+	input      string    // the string being scanned
+	leftDelim  string    // start of action
+	rightDelim string    // end of action
+	state      stateFn   // the next lexing function to enter
+	pos        Pos       // current position in the input
+	start      Pos       // start position of this item
+	width      Pos       // width of last rune read from input
+	lastPos    Pos       // position of most recent item returned by nextItem
+	items      chan item // channel of scanned items
+	parenDepth int       // nesting depth of ( ) exprs
+}
+
+// next returns the next rune in the input.
+func (l *lexer) next() rune {
+	if int(l.pos) >= len(l.input) {
+		l.width = 0
+		return eof
+	}
+	r, w := utf8.DecodeRuneInString(l.input[l.pos:])
+	l.width = Pos(w)
+	l.pos += l.width
+	return r
+}
+
+// peek returns but does not consume the next rune in the input.
+func (l *lexer) peek() rune {
+	r := l.next()
+	l.backup()
+	return r
+}
+
+// backup steps back one rune. Can only be called once per call of next.
+func (l *lexer) backup() {
+	l.pos -= l.width
+}
+
+// emit passes an item back to the client.
+func (l *lexer) emit(t itemType) {
+	l.items <- item{t, l.start, l.input[l.start:l.pos]}
+	l.start = l.pos
+}
+
+// ignore skips over the pending input before this point.
+func (l *lexer) ignore() {
+	l.start = l.pos
+}
+
+// accept consumes the next rune if it's from the valid set.
+func (l *lexer) accept(valid string) bool {
+	if strings.IndexRune(valid, l.next()) >= 0 {
+		return true
+	}
+	l.backup()
+	return false
+}
+
+// acceptRun consumes a run of runes from the valid set.
+func (l *lexer) acceptRun(valid string) {
+	for strings.IndexRune(valid, l.next()) >= 0 {
+	}
+	l.backup()
+}
+
+// lineNumber reports which line we're on, based on the position of
+// the previous item returned by nextItem. Doing it this way
+// means we don't have to worry about peek double counting.
+func (l *lexer) lineNumber() int {
+	return 1 + strings.Count(l.input[:l.lastPos], "\n")
+}
+
+// errorf returns an error token and terminates the scan by passing
+// back a nil pointer that will be the next state, terminating l.nextItem.
+func (l *lexer) errorf(format string, args ...interface{}) stateFn {
+	l.items <- item{itemError, l.start, fmt.Sprintf(format, args...)}
+	return nil
+}
+
+// nextItem returns the next item from the input.
+func (l *lexer) nextItem() item {
+	item := <-l.items
+	l.lastPos = item.pos
+	return item
+}
+
+// lex creates a new scanner for the input string.
+func lex(name, input, left, right string) *lexer {
+	if left == "" {
+		left = leftDelim
+	}
+	if right == "" {
+		right = rightDelim
+	}
+	l := &lexer{
+		name:       name,
+		input:      input,
+		leftDelim:  left,
+		rightDelim: right,
+		items:      make(chan item),
+	}
+	go l.run()
+	return l
+}
+
+// run runs the state machine for the lexer.
+func (l *lexer) run() {
+	for l.state = lexText; l.state != nil; {
+		l.state = l.state(l)
+	}
+}
+
+// state functions
+
+const (
+	leftDelim    = "{{"
+	rightDelim   = "}}"
+	leftComment  = "/*"
+	rightComment = "*/"
+)
+
+// lexText scans until an opening action delimiter, "{{".
+func lexText(l *lexer) stateFn {
+	for {
+		if strings.HasPrefix(l.input[l.pos:], l.leftDelim) {
+			if l.pos > l.start {
+				l.emit(itemText)
+			}
+			return lexLeftDelim
+		}
+		if l.next() == eof {
+			break
+		}
+	}
+	// Correctly reached EOF.
+	if l.pos > l.start {
+		l.emit(itemText)
+	}
+	l.emit(itemEOF)
+	return nil
+}
+
+// lexLeftDelim scans the left delimiter, which is known to be present.
+func lexLeftDelim(l *lexer) stateFn {
+	l.pos += Pos(len(l.leftDelim))
+	if strings.HasPrefix(l.input[l.pos:], leftComment) {
+		return lexComment
+	}
+	l.emit(itemLeftDelim)
+	l.parenDepth = 0
+	return lexInsideAction
+}
+
+// lexComment scans a comment. The left comment marker is known to be present.
+func lexComment(l *lexer) stateFn {
+	l.pos += Pos(len(leftComment))
+	i := strings.Index(l.input[l.pos:], rightComment)
+	if i < 0 {
+		return l.errorf("unclosed comment")
+	}
+	l.pos += Pos(i + len(rightComment))
+	if !strings.HasPrefix(l.input[l.pos:], l.rightDelim) {
+		return l.errorf("comment ends before closing delimiter")
+
+	}
+	l.pos += Pos(len(l.rightDelim))
+	l.ignore()
+	return lexText
+}
+
+// lexRightDelim scans the right delimiter, which is known to be present.
+func lexRightDelim(l *lexer) stateFn {
+	l.pos += Pos(len(l.rightDelim))
+	l.emit(itemRightDelim)
+	if l.peek() == '\\' {
+		l.pos++
+		l.emit(itemElideNewline)
+	}
+	return lexText
+}
+
+// lexInsideAction scans the elements inside action delimiters.
+func lexInsideAction(l *lexer) stateFn {
+	// Either number, quoted string, or identifier.
+	// Spaces separate arguments; runs of spaces turn into itemSpace.
+	// Pipe symbols separate and are emitted.
+	if strings.HasPrefix(l.input[l.pos:], l.rightDelim+"\\") || strings.HasPrefix(l.input[l.pos:], l.rightDelim) {
+		if l.parenDepth == 0 {
+			return lexRightDelim
+		}
+		return l.errorf("unclosed left paren")
+	}
+	switch r := l.next(); {
+	case r == eof || isEndOfLine(r):
+		return l.errorf("unclosed action")
+	case isSpace(r):
+		return lexSpace
+	case r == ':':
+		if l.next() != '=' {
+			return l.errorf("expected :=")
+		}
+		l.emit(itemColonEquals)
+	case r == '|':
+		l.emit(itemPipe)
+	case r == '"':
+		return lexQuote
+	case r == '`':
+		return lexRawQuote
+	case r == '$':
+		return lexVariable
+	case r == '\'':
+		return lexChar
+	case r == '.':
+		// special look-ahead for ".field" so we don't break l.backup().
+		if l.pos < Pos(len(l.input)) {
+			r := l.input[l.pos]
+			if r < '0' || '9' < r {
+				return lexField
+			}
+		}
+		fallthrough // '.' can start a number.
+	case r == '+' || r == '-' || ('0' <= r && r <= '9'):
+		l.backup()
+		return lexNumber
+	case isAlphaNumeric(r):
+		l.backup()
+		return lexIdentifier
+	case r == '(':
+		l.emit(itemLeftParen)
+		l.parenDepth++
+		return lexInsideAction
+	case r == ')':
+		l.emit(itemRightParen)
+		l.parenDepth--
+		if l.parenDepth < 0 {
+			return l.errorf("unexpected right paren %#U", r)
+		}
+		return lexInsideAction
+	case r <= unicode.MaxASCII && unicode.IsPrint(r):
+		l.emit(itemChar)
+		return lexInsideAction
+	default:
+		return l.errorf("unrecognized character in action: %#U", r)
+	}
+	return lexInsideAction
+}
+
+// lexSpace scans a run of space characters.
+// One space has already been seen.
+func lexSpace(l *lexer) stateFn {
+	for isSpace(l.peek()) {
+		l.next()
+	}
+	l.emit(itemSpace)
+	return lexInsideAction
+}
+
+// lexIdentifier scans an alphanumeric.
+func lexIdentifier(l *lexer) stateFn {
+Loop:
+	for {
+		switch r := l.next(); {
+		case isAlphaNumeric(r):
+			// absorb.
+		default:
+			l.backup()
+			word := l.input[l.start:l.pos]
+			if !l.atTerminator() {
+				return l.errorf("bad character %#U", r)
+			}
+			switch {
+			case key[word] > itemKeyword:
+				l.emit(key[word])
+			case word[0] == '.':
+				l.emit(itemField)
+			case word == "true", word == "false":
+				l.emit(itemBool)
+			default:
+				l.emit(itemIdentifier)
+			}
+			break Loop
+		}
+	}
+	return lexInsideAction
+}
+
+// lexField scans a field: .Alphanumeric.
+// The . has been scanned.
+func lexField(l *lexer) stateFn {
+	return lexFieldOrVariable(l, itemField)
+}
+
+// lexVariable scans a Variable: $Alphanumeric.
+// The $ has been scanned.
+func lexVariable(l *lexer) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "$".
+		l.emit(itemVariable)
+		return lexInsideAction
+	}
+	return lexFieldOrVariable(l, itemVariable)
+}
+
+// lexVariable scans a field or variable: [.$]Alphanumeric.
+// The . or $ has been scanned.
+func lexFieldOrVariable(l *lexer, typ itemType) stateFn {
+	if l.atTerminator() { // Nothing interesting follows -> "." or "$".
+		if typ == itemVariable {
+			l.emit(itemVariable)
+		} else {
+			l.emit(itemDot)
+		}
+		return lexInsideAction
+	}
+	var r rune
+	for {
+		r = l.next()
+		if !isAlphaNumeric(r) {
+			l.backup()
+			break
+		}
+	}
+	if !l.atTerminator() {
+		return l.errorf("bad character %#U", r)
+	}
+	l.emit(typ)
+	return lexInsideAction
+}
+
+// atTerminator reports whether the input is at valid termination character to
+// appear after an identifier. Breaks .X.Y into two pieces. Also catches cases
+// like "$x+2" not being acceptable without a space, in case we decide one
+// day to implement arithmetic.
+func (l *lexer) atTerminator() bool {
+	r := l.peek()
+	if isSpace(r) || isEndOfLine(r) {
+		return true
+	}
+	switch r {
+	case eof, '.', ',', '|', ':', ')', '(':
+		return true
+	}
+	// Does r start the delimiter? This can be ambiguous (with delim=="//", $x/2 will
+	// succeed but should fail) but only in extremely rare cases caused by willfully
+	// bad choice of delimiter.
+	if rd, _ := utf8.DecodeRuneInString(l.rightDelim); rd == r {
+		return true
+	}
+	return false
+}
+
+// lexChar scans a character constant. The initial quote is already
+// scanned. Syntax checking is done by the parser.
+func lexChar(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated character constant")
+		case '\'':
+			break Loop
+		}
+	}
+	l.emit(itemCharConstant)
+	return lexInsideAction
+}
+
+// lexNumber scans a number: decimal, octal, hex, float, or imaginary. This
+// isn't a perfect number scanner - for instance it accepts "." and "0x0.2"
+// and "089" - but when it's wrong the input is invalid and the parser (via
+// strconv) will notice.
+func lexNumber(l *lexer) stateFn {
+	if !l.scanNumber() {
+		return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+	}
+	if sign := l.peek(); sign == '+' || sign == '-' {
+		// Complex: 1+2i. No spaces, must end in 'i'.
+		if !l.scanNumber() || l.input[l.pos-1] != 'i' {
+			return l.errorf("bad number syntax: %q", l.input[l.start:l.pos])
+		}
+		l.emit(itemComplex)
+	} else {
+		l.emit(itemNumber)
+	}
+	return lexInsideAction
+}
+
+func (l *lexer) scanNumber() bool {
+	// Optional leading sign.
+	l.accept("+-")
+	// Is it hex?
+	digits := "0123456789"
+	if l.accept("0") && l.accept("xX") {
+		digits = "0123456789abcdefABCDEF"
+	}
+	l.acceptRun(digits)
+	if l.accept(".") {
+		l.acceptRun(digits)
+	}
+	if l.accept("eE") {
+		l.accept("+-")
+		l.acceptRun("0123456789")
+	}
+	// Is it imaginary?
+	l.accept("i")
+	// Next thing mustn't be alphanumeric.
+	if isAlphaNumeric(l.peek()) {
+		l.next()
+		return false
+	}
+	return true
+}
+
+// lexQuote scans a quoted string.
+func lexQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case '\\':
+			if r := l.next(); r != eof && r != '\n' {
+				break
+			}
+			fallthrough
+		case eof, '\n':
+			return l.errorf("unterminated quoted string")
+		case '"':
+			break Loop
+		}
+	}
+	l.emit(itemString)
+	return lexInsideAction
+}
+
+// lexRawQuote scans a raw quoted string.
+func lexRawQuote(l *lexer) stateFn {
+Loop:
+	for {
+		switch l.next() {
+		case eof, '\n':
+			return l.errorf("unterminated raw quoted string")
+		case '`':
+			break Loop
+		}
+	}
+	l.emit(itemRawString)
+	return lexInsideAction
+}
+
+// isSpace reports whether r is a space character.
+func isSpace(r rune) bool {
+	return r == ' ' || r == '\t'
+}
+
+// isEndOfLine reports whether r is an end-of-line character.
+func isEndOfLine(r rune) bool {
+	return r == '\r' || r == '\n'
+}
+
+// isAlphaNumeric reports whether r is an alphabetic, digit, or underscore.
+func isAlphaNumeric(r rune) bool {
+	return r == '_' || unicode.IsLetter(r) || unicode.IsDigit(r)
+}

vendor/github.com/alecthomas/template/parse/node.go

@@ -0,0 +1,834 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Parse nodes.
+
+package parse
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+var textFormat = "%s" // Changed to "%q" in tests for better error messages.
+
+// A Node is an element in the parse tree. The interface is trivial.
+// The interface contains an unexported method so that only
+// types local to this package can satisfy it.
+type Node interface {
+	Type() NodeType
+	String() string
+	// Copy does a deep copy of the Node and all its components.
+	// To avoid type assertions, some XxxNodes also have specialized
+	// CopyXxx methods that return *XxxNode.
+	Copy() Node
+	Position() Pos // byte position of start of node in full original input string
+	// tree returns the containing *Tree.
+	// It is unexported so all implementations of Node are in this package.
+	tree() *Tree
+}
+
+// NodeType identifies the type of a parse tree node.
+type NodeType int
+
+// Pos represents a byte position in the original input text from which
+// this template was parsed.
+type Pos int
+
+func (p Pos) Position() Pos {
+	return p
+}
+
+// Type returns itself and provides an easy default implementation
+// for embedding in a Node. Embedded in all non-trivial Nodes.
+func (t NodeType) Type() NodeType {
+	return t
+}
+
+const (
+	NodeText       NodeType = iota // Plain text.
+	NodeAction                     // A non-control action such as a field evaluation.
+	NodeBool                       // A boolean constant.
+	NodeChain                      // A sequence of field accesses.
+	NodeCommand                    // An element of a pipeline.
+	NodeDot                        // The cursor, dot.
+	nodeElse                       // An else action. Not added to tree.
+	nodeEnd                        // An end action. Not added to tree.
+	NodeField                      // A field or method name.
+	NodeIdentifier                 // An identifier; always a function name.
+	NodeIf                         // An if action.
+	NodeList                       // A list of Nodes.
+	NodeNil                        // An untyped nil constant.
+	NodeNumber                     // A numerical constant.
+	NodePipe                       // A pipeline of commands.
+	NodeRange                      // A range action.
+	NodeString                     // A string constant.
+	NodeTemplate                   // A template invocation action.
+	NodeVariable                   // A $ variable.
+	NodeWith                       // A with action.
+)
+
+// Nodes.
+
+// ListNode holds a sequence of nodes.
+type ListNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Nodes []Node // The element nodes in lexical order.
+}
+
+func (t *Tree) newList(pos Pos) *ListNode {
+	return &ListNode{tr: t, NodeType: NodeList, Pos: pos}
+}
+
+func (l *ListNode) append(n Node) {
+	l.Nodes = append(l.Nodes, n)
+}
+
+func (l *ListNode) tree() *Tree {
+	return l.tr
+}
+
+func (l *ListNode) String() string {
+	b := new(bytes.Buffer)
+	for _, n := range l.Nodes {
+		fmt.Fprint(b, n)
+	}
+	return b.String()
+}
+
+func (l *ListNode) CopyList() *ListNode {
+	if l == nil {
+		return l
+	}
+	n := l.tr.newList(l.Pos)
+	for _, elem := range l.Nodes {
+		n.append(elem.Copy())
+	}
+	return n
+}
+
+func (l *ListNode) Copy() Node {
+	return l.CopyList()
+}
+
+// TextNode holds plain text.
+type TextNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Text []byte // The text; may span newlines.
+}
+
+func (t *Tree) newText(pos Pos, text string) *TextNode {
+	return &TextNode{tr: t, NodeType: NodeText, Pos: pos, Text: []byte(text)}
+}
+
+func (t *TextNode) String() string {
+	return fmt.Sprintf(textFormat, t.Text)
+}
+
+func (t *TextNode) tree() *Tree {
+	return t.tr
+}
+
+func (t *TextNode) Copy() Node {
+	return &TextNode{tr: t.tr, NodeType: NodeText, Pos: t.Pos, Text: append([]byte{}, t.Text...)}
+}
+
+// PipeNode holds a pipeline with optional declaration
+type PipeNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int             // The line number in the input (deprecated; kept for compatibility)
+	Decl []*VariableNode // Variable declarations in lexical order.
+	Cmds []*CommandNode  // The commands in lexical order.
+}
+
+func (t *Tree) newPipeline(pos Pos, line int, decl []*VariableNode) *PipeNode {
+	return &PipeNode{tr: t, NodeType: NodePipe, Pos: pos, Line: line, Decl: decl}
+}
+
+func (p *PipeNode) append(command *CommandNode) {
+	p.Cmds = append(p.Cmds, command)
+}
+
+func (p *PipeNode) String() string {
+	s := ""
+	if len(p.Decl) > 0 {
+		for i, v := range p.Decl {
+			if i > 0 {
+				s += ", "
+			}
+			s += v.String()
+		}
+		s += " := "
+	}
+	for i, c := range p.Cmds {
+		if i > 0 {
+			s += " | "
+		}
+		s += c.String()
+	}
+	return s
+}
+
+func (p *PipeNode) tree() *Tree {
+	return p.tr
+}
+
+func (p *PipeNode) CopyPipe() *PipeNode {
+	if p == nil {
+		return p
+	}
+	var decl []*VariableNode
+	for _, d := range p.Decl {
+		decl = append(decl, d.Copy().(*VariableNode))
+	}
+	n := p.tr.newPipeline(p.Pos, p.Line, decl)
+	for _, c := range p.Cmds {
+		n.append(c.Copy().(*CommandNode))
+	}
+	return n
+}
+
+func (p *PipeNode) Copy() Node {
+	return p.CopyPipe()
+}
+
+// ActionNode holds an action (something bounded by delimiters).
+// Control actions have their own nodes; ActionNode represents simple
+// ones such as field evaluations and parenthesized pipelines.
+type ActionNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int       // The line number in the input (deprecated; kept for compatibility)
+	Pipe *PipeNode // The pipeline in the action.
+}
+
+func (t *Tree) newAction(pos Pos, line int, pipe *PipeNode) *ActionNode {
+	return &ActionNode{tr: t, NodeType: NodeAction, Pos: pos, Line: line, Pipe: pipe}
+}
+
+func (a *ActionNode) String() string {
+	return fmt.Sprintf("{{%s}}", a.Pipe)
+
+}
+
+func (a *ActionNode) tree() *Tree {
+	return a.tr
+}
+
+func (a *ActionNode) Copy() Node {
+	return a.tr.newAction(a.Pos, a.Line, a.Pipe.CopyPipe())
+
+}
+
+// CommandNode holds a command (a pipeline inside an evaluating action).
+type CommandNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Args []Node // Arguments in lexical order: Identifier, field, or constant.
+}
+
+func (t *Tree) newCommand(pos Pos) *CommandNode {
+	return &CommandNode{tr: t, NodeType: NodeCommand, Pos: pos}
+}
+
+func (c *CommandNode) append(arg Node) {
+	c.Args = append(c.Args, arg)
+}
+
+func (c *CommandNode) String() string {
+	s := ""
+	for i, arg := range c.Args {
+		if i > 0 {
+			s += " "
+		}
+		if arg, ok := arg.(*PipeNode); ok {
+			s += "(" + arg.String() + ")"
+			continue
+		}
+		s += arg.String()
+	}
+	return s
+}
+
+func (c *CommandNode) tree() *Tree {
+	return c.tr
+}
+
+func (c *CommandNode) Copy() Node {
+	if c == nil {
+		return c
+	}
+	n := c.tr.newCommand(c.Pos)
+	for _, c := range c.Args {
+		n.append(c.Copy())
+	}
+	return n
+}
+
+// IdentifierNode holds an identifier.
+type IdentifierNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident string // The identifier's name.
+}
+
+// NewIdentifier returns a new IdentifierNode with the given identifier name.
+func NewIdentifier(ident string) *IdentifierNode {
+	return &IdentifierNode{NodeType: NodeIdentifier, Ident: ident}
+}
+
+// SetPos sets the position. NewIdentifier is a public method so we can't modify its signature.
+// Chained for convenience.
+// TODO: fix one day?
+func (i *IdentifierNode) SetPos(pos Pos) *IdentifierNode {
+	i.Pos = pos
+	return i
+}
+
+// SetTree sets the parent tree for the node. NewIdentifier is a public method so we can't modify its signature.
+// Chained for convenience.
+// TODO: fix one day?
+func (i *IdentifierNode) SetTree(t *Tree) *IdentifierNode {
+	i.tr = t
+	return i
+}
+
+func (i *IdentifierNode) String() string {
+	return i.Ident
+}
+
+func (i *IdentifierNode) tree() *Tree {
+	return i.tr
+}
+
+func (i *IdentifierNode) Copy() Node {
+	return NewIdentifier(i.Ident).SetTree(i.tr).SetPos(i.Pos)
+}
+
+// VariableNode holds a list of variable names, possibly with chained field
+// accesses. The dollar sign is part of the (first) name.
+type VariableNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident []string // Variable name and fields in lexical order.
+}
+
+func (t *Tree) newVariable(pos Pos, ident string) *VariableNode {
+	return &VariableNode{tr: t, NodeType: NodeVariable, Pos: pos, Ident: strings.Split(ident, ".")}
+}
+
+func (v *VariableNode) String() string {
+	s := ""
+	for i, id := range v.Ident {
+		if i > 0 {
+			s += "."
+		}
+		s += id
+	}
+	return s
+}
+
+func (v *VariableNode) tree() *Tree {
+	return v.tr
+}
+
+func (v *VariableNode) Copy() Node {
+	return &VariableNode{tr: v.tr, NodeType: NodeVariable, Pos: v.Pos, Ident: append([]string{}, v.Ident...)}
+}
+
+// DotNode holds the special identifier '.'.
+type DotNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newDot(pos Pos) *DotNode {
+	return &DotNode{tr: t, NodeType: NodeDot, Pos: pos}
+}
+
+func (d *DotNode) Type() NodeType {
+	// Override method on embedded NodeType for API compatibility.
+	// TODO: Not really a problem; could change API without effect but
+	// api tool complains.
+	return NodeDot
+}
+
+func (d *DotNode) String() string {
+	return "."
+}
+
+func (d *DotNode) tree() *Tree {
+	return d.tr
+}
+
+func (d *DotNode) Copy() Node {
+	return d.tr.newDot(d.Pos)
+}
+
+// NilNode holds the special identifier 'nil' representing an untyped nil constant.
+type NilNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newNil(pos Pos) *NilNode {
+	return &NilNode{tr: t, NodeType: NodeNil, Pos: pos}
+}
+
+func (n *NilNode) Type() NodeType {
+	// Override method on embedded NodeType for API compatibility.
+	// TODO: Not really a problem; could change API without effect but
+	// api tool complains.
+	return NodeNil
+}
+
+func (n *NilNode) String() string {
+	return "nil"
+}
+
+func (n *NilNode) tree() *Tree {
+	return n.tr
+}
+
+func (n *NilNode) Copy() Node {
+	return n.tr.newNil(n.Pos)
+}
+
+// FieldNode holds a field (identifier starting with '.').
+// The names may be chained ('.x.y').
+// The period is dropped from each ident.
+type FieldNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Ident []string // The identifiers in lexical order.
+}
+
+func (t *Tree) newField(pos Pos, ident string) *FieldNode {
+	return &FieldNode{tr: t, NodeType: NodeField, Pos: pos, Ident: strings.Split(ident[1:], ".")} // [1:] to drop leading period
+}
+
+func (f *FieldNode) String() string {
+	s := ""
+	for _, id := range f.Ident {
+		s += "." + id
+	}
+	return s
+}
+
+func (f *FieldNode) tree() *Tree {
+	return f.tr
+}
+
+func (f *FieldNode) Copy() Node {
+	return &FieldNode{tr: f.tr, NodeType: NodeField, Pos: f.Pos, Ident: append([]string{}, f.Ident...)}
+}
+
+// ChainNode holds a term followed by a chain of field accesses (identifier starting with '.').
+// The names may be chained ('.x.y').
+// The periods are dropped from each ident.
+type ChainNode struct {
+	NodeType
+	Pos
+	tr    *Tree
+	Node  Node
+	Field []string // The identifiers in lexical order.
+}
+
+func (t *Tree) newChain(pos Pos, node Node) *ChainNode {
+	return &ChainNode{tr: t, NodeType: NodeChain, Pos: pos, Node: node}
+}
+
+// Add adds the named field (which should start with a period) to the end of the chain.
+func (c *ChainNode) Add(field string) {
+	if len(field) == 0 || field[0] != '.' {
+		panic("no dot in field")
+	}
+	field = field[1:] // Remove leading dot.
+	if field == "" {
+		panic("empty field")
+	}
+	c.Field = append(c.Field, field)
+}
+
+func (c *ChainNode) String() string {
+	s := c.Node.String()
+	if _, ok := c.Node.(*PipeNode); ok {
+		s = "(" + s + ")"
+	}
+	for _, field := range c.Field {
+		s += "." + field
+	}
+	return s
+}
+
+func (c *ChainNode) tree() *Tree {
+	return c.tr
+}
+
+func (c *ChainNode) Copy() Node {
+	return &ChainNode{tr: c.tr, NodeType: NodeChain, Pos: c.Pos, Node: c.Node, Field: append([]string{}, c.Field...)}
+}
+
+// BoolNode holds a boolean constant.
+type BoolNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	True bool // The value of the boolean constant.
+}
+
+func (t *Tree) newBool(pos Pos, true bool) *BoolNode {
+	return &BoolNode{tr: t, NodeType: NodeBool, Pos: pos, True: true}
+}
+
+func (b *BoolNode) String() string {
+	if b.True {
+		return "true"
+	}
+	return "false"
+}
+
+func (b *BoolNode) tree() *Tree {
+	return b.tr
+}
+
+func (b *BoolNode) Copy() Node {
+	return b.tr.newBool(b.Pos, b.True)
+}
+
+// NumberNode holds a number: signed or unsigned integer, float, or complex.
+// The value is parsed and stored under all the types that can represent the value.
+// This simulates in a small amount of code the behavior of Go's ideal constants.
+type NumberNode struct {
+	NodeType
+	Pos
+	tr         *Tree
+	IsInt      bool       // Number has an integral value.
+	IsUint     bool       // Number has an unsigned integral value.
+	IsFloat    bool       // Number has a floating-point value.
+	IsComplex  bool       // Number is complex.
+	Int64      int64      // The signed integer value.
+	Uint64     uint64     // The unsigned integer value.
+	Float64    float64    // The floating-point value.
+	Complex128 complex128 // The complex value.
+	Text       string     // The original textual representation from the input.
+}
+
+func (t *Tree) newNumber(pos Pos, text string, typ itemType) (*NumberNode, error) {
+	n := &NumberNode{tr: t, NodeType: NodeNumber, Pos: pos, Text: text}
+	switch typ {
+	case itemCharConstant:
+		rune, _, tail, err := strconv.UnquoteChar(text[1:], text[0])
+		if err != nil {
+			return nil, err
+		}
+		if tail != "'" {
+			return nil, fmt.Errorf("malformed character constant: %s", text)
+		}
+		n.Int64 = int64(rune)
+		n.IsInt = true
+		n.Uint64 = uint64(rune)
+		n.IsUint = true
+		n.Float64 = float64(rune) // odd but those are the rules.
+		n.IsFloat = true
+		return n, nil
+	case itemComplex:
+		// fmt.Sscan can parse the pair, so let it do the work.
+		if _, err := fmt.Sscan(text, &n.Complex128); err != nil {
+			return nil, err
+		}
+		n.IsComplex = true
+		n.simplifyComplex()
+		return n, nil
+	}
+	// Imaginary constants can only be complex unless they are zero.
+	if len(text) > 0 && text[len(text)-1] == 'i' {
+		f, err := strconv.ParseFloat(text[:len(text)-1], 64)
+		if err == nil {
+			n.IsComplex = true
+			n.Complex128 = complex(0, f)
+			n.simplifyComplex()
+			return n, nil
+		}
+	}
+	// Do integer test first so we get 0x123 etc.
+	u, err := strconv.ParseUint(text, 0, 64) // will fail for -0; fixed below.
+	if err == nil {
+		n.IsUint = true
+		n.Uint64 = u
+	}
+	i, err := strconv.ParseInt(text, 0, 64)
+	if err == nil {
+		n.IsInt = true
+		n.Int64 = i
+		if i == 0 {
+			n.IsUint = true // in case of -0.
+			n.Uint64 = u
+		}
+	}
+	// If an integer extraction succeeded, promote the float.
+	if n.IsInt {
+		n.IsFloat = true
+		n.Float64 = float64(n.Int64)
+	} else if n.IsUint {
+		n.IsFloat = true
+		n.Float64 = float64(n.Uint64)
+	} else {
+		f, err := strconv.ParseFloat(text, 64)
+		if err == nil {
+			n.IsFloat = true
+			n.Float64 = f
+			// If a floating-point extraction succeeded, extract the int if needed.
+			if !n.IsInt && float64(int64(f)) == f {
+				n.IsInt = true
+				n.Int64 = int64(f)
+			}
+			if !n.IsUint && float64(uint64(f)) == f {
+				n.IsUint = true
+				n.Uint64 = uint64(f)
+			}
+		}
+	}
+	if !n.IsInt && !n.IsUint && !n.IsFloat {
+		return nil, fmt.Errorf("illegal number syntax: %q", text)
+	}
+	return n, nil
+}
+
+// simplifyComplex pulls out any other types that are represented by the complex number.
+// These all require that the imaginary part be zero.
+func (n *NumberNode) simplifyComplex() {
+	n.IsFloat = imag(n.Complex128) == 0
+	if n.IsFloat {
+		n.Float64 = real(n.Complex128)
+		n.IsInt = float64(int64(n.Float64)) == n.Float64
+		if n.IsInt {
+			n.Int64 = int64(n.Float64)
+		}
+		n.IsUint = float64(uint64(n.Float64)) == n.Float64
+		if n.IsUint {
+			n.Uint64 = uint64(n.Float64)
+		}
+	}
+}
+
+func (n *NumberNode) String() string {
+	return n.Text
+}
+
+func (n *NumberNode) tree() *Tree {
+	return n.tr
+}
+
+func (n *NumberNode) Copy() Node {
+	nn := new(NumberNode)
+	*nn = *n // Easy, fast, correct.
+	return nn
+}
+
+// StringNode holds a string constant. The value has been "unquoted".
+type StringNode struct {
+	NodeType
+	Pos
+	tr     *Tree
+	Quoted string // The original text of the string, with quotes.
+	Text   string // The string, after quote processing.
+}
+
+func (t *Tree) newString(pos Pos, orig, text string) *StringNode {
+	return &StringNode{tr: t, NodeType: NodeString, Pos: pos, Quoted: orig, Text: text}
+}
+
+func (s *StringNode) String() string {
+	return s.Quoted
+}
+
+func (s *StringNode) tree() *Tree {
+	return s.tr
+}
+
+func (s *StringNode) Copy() Node {
+	return s.tr.newString(s.Pos, s.Quoted, s.Text)
+}
+
+// endNode represents an {{end}} action.
+// It does not appear in the final parse tree.
+type endNode struct {
+	NodeType
+	Pos
+	tr *Tree
+}
+
+func (t *Tree) newEnd(pos Pos) *endNode {
+	return &endNode{tr: t, NodeType: nodeEnd, Pos: pos}
+}
+
+func (e *endNode) String() string {
+	return "{{end}}"
+}
+
+func (e *endNode) tree() *Tree {
+	return e.tr
+}
+
+func (e *endNode) Copy() Node {
+	return e.tr.newEnd(e.Pos)
+}
+
+// elseNode represents an {{else}} action. Does not appear in the final tree.
+type elseNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int // The line number in the input (deprecated; kept for compatibility)
+}
+
+func (t *Tree) newElse(pos Pos, line int) *elseNode {
+	return &elseNode{tr: t, NodeType: nodeElse, Pos: pos, Line: line}
+}
+
+func (e *elseNode) Type() NodeType {
+	return nodeElse
+}
+
+func (e *elseNode) String() string {
+	return "{{else}}"
+}
+
+func (e *elseNode) tree() *Tree {
+	return e.tr
+}
+
+func (e *elseNode) Copy() Node {
+	return e.tr.newElse(e.Pos, e.Line)
+}
+
+// BranchNode is the common representation of if, range, and with.
+type BranchNode struct {
+	NodeType
+	Pos
+	tr       *Tree
+	Line     int       // The line number in the input (deprecated; kept for compatibility)
+	Pipe     *PipeNode // The pipeline to be evaluated.
+	List     *ListNode // What to execute if the value is non-empty.
+	ElseList *ListNode // What to execute if the value is empty (nil if absent).
+}
+
+func (b *BranchNode) String() string {
+	name := ""
+	switch b.NodeType {
+	case NodeIf:
+		name = "if"
+	case NodeRange:
+		name = "range"
+	case NodeWith:
+		name = "with"
+	default:
+		panic("unknown branch type")
+	}
+	if b.ElseList != nil {
+		return fmt.Sprintf("{{%s %s}}%s{{else}}%s{{end}}", name, b.Pipe, b.List, b.ElseList)
+	}
+	return fmt.Sprintf("{{%s %s}}%s{{end}}", name, b.Pipe, b.List)
+}
+
+func (b *BranchNode) tree() *Tree {
+	return b.tr
+}
+
+func (b *BranchNode) Copy() Node {
+	switch b.NodeType {
+	case NodeIf:
+		return b.tr.newIf(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	case NodeRange:
+		return b.tr.newRange(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	case NodeWith:
+		return b.tr.newWith(b.Pos, b.Line, b.Pipe, b.List, b.ElseList)
+	default:
+		panic("unknown branch type")
+	}
+}
+
+// IfNode represents an {{if}} action and its commands.
+type IfNode struct {
+	BranchNode
+}
+
+func (t *Tree) newIf(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *IfNode {
+	return &IfNode{BranchNode{tr: t, NodeType: NodeIf, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (i *IfNode) Copy() Node {
+	return i.tr.newIf(i.Pos, i.Line, i.Pipe.CopyPipe(), i.List.CopyList(), i.ElseList.CopyList())
+}
+
+// RangeNode represents a {{range}} action and its commands.
+type RangeNode struct {
+	BranchNode
+}
+
+func (t *Tree) newRange(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *RangeNode {
+	return &RangeNode{BranchNode{tr: t, NodeType: NodeRange, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (r *RangeNode) Copy() Node {
+	return r.tr.newRange(r.Pos, r.Line, r.Pipe.CopyPipe(), r.List.CopyList(), r.ElseList.CopyList())
+}
+
+// WithNode represents a {{with}} action and its commands.
+type WithNode struct {
+	BranchNode
+}
+
+func (t *Tree) newWith(pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) *WithNode {
+	return &WithNode{BranchNode{tr: t, NodeType: NodeWith, Pos: pos, Line: line, Pipe: pipe, List: list, ElseList: elseList}}
+}
+
+func (w *WithNode) Copy() Node {
+	return w.tr.newWith(w.Pos, w.Line, w.Pipe.CopyPipe(), w.List.CopyList(), w.ElseList.CopyList())
+}
+
+// TemplateNode represents a {{template}} action.
+type TemplateNode struct {
+	NodeType
+	Pos
+	tr   *Tree
+	Line int       // The line number in the input (deprecated; kept for compatibility)
+	Name string    // The name of the template (unquoted).
+	Pipe *PipeNode // The command to evaluate as dot for the template.
+}
+
+func (t *Tree) newTemplate(pos Pos, line int, name string, pipe *PipeNode) *TemplateNode {
+	return &TemplateNode{tr: t, NodeType: NodeTemplate, Pos: pos, Line: line, Name: name, Pipe: pipe}
+}
+
+func (t *TemplateNode) String() string {
+	if t.Pipe == nil {
+		return fmt.Sprintf("{{template %q}}", t.Name)
+	}
+	return fmt.Sprintf("{{template %q %s}}", t.Name, t.Pipe)
+}
+
+func (t *TemplateNode) tree() *Tree {
+	return t.tr
+}
+
+func (t *TemplateNode) Copy() Node {
+	return t.tr.newTemplate(t.Pos, t.Line, t.Name, t.Pipe.CopyPipe())
+}

vendor/github.com/alecthomas/template/parse/parse.go

@@ -0,0 +1,700 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package parse builds parse trees for templates as defined by text/template
+// and html/template. Clients should use those packages to construct templates
+// rather than this one, which provides shared internal data structures not
+// intended for general use.
+package parse
+
+import (
+	"bytes"
+	"fmt"
+	"runtime"
+	"strconv"
+	"strings"
+)
+
+// Tree is the representation of a single parsed template.
+type Tree struct {
+	Name      string    // name of the template represented by the tree.
+	ParseName string    // name of the top-level template during parsing, for error messages.
+	Root      *ListNode // top-level root of the tree.
+	text      string    // text parsed to create the template (or its parent)
+	// Parsing only; cleared after parse.
+	funcs     []map[string]interface{}
+	lex       *lexer
+	token     [3]item // three-token lookahead for parser.
+	peekCount int
+	vars      []string // variables defined at the moment.
+}
+
+// Copy returns a copy of the Tree. Any parsing state is discarded.
+func (t *Tree) Copy() *Tree {
+	if t == nil {
+		return nil
+	}
+	return &Tree{
+		Name:      t.Name,
+		ParseName: t.ParseName,
+		Root:      t.Root.CopyList(),
+		text:      t.text,
+	}
+}
+
+// Parse returns a map from template name to parse.Tree, created by parsing the
+// templates described in the argument string. The top-level template will be
+// given the specified name. If an error is encountered, parsing stops and an
+// empty map is returned with the error.
+func Parse(name, text, leftDelim, rightDelim string, funcs ...map[string]interface{}) (treeSet map[string]*Tree, err error) {
+	treeSet = make(map[string]*Tree)
+	t := New(name)
+	t.text = text
+	_, err = t.Parse(text, leftDelim, rightDelim, treeSet, funcs...)
+	return
+}
+
+// next returns the next token.
+func (t *Tree) next() item {
+	if t.peekCount > 0 {
+		t.peekCount--
+	} else {
+		t.token[0] = t.lex.nextItem()
+	}
+	return t.token[t.peekCount]
+}
+
+// backup backs the input stream up one token.
+func (t *Tree) backup() {
+	t.peekCount++
+}
+
+// backup2 backs the input stream up two tokens.
+// The zeroth token is already there.
+func (t *Tree) backup2(t1 item) {
+	t.token[1] = t1
+	t.peekCount = 2
+}
+
+// backup3 backs the input stream up three tokens
+// The zeroth token is already there.
+func (t *Tree) backup3(t2, t1 item) { // Reverse order: we're pushing back.
+	t.token[1] = t1
+	t.token[2] = t2
+	t.peekCount = 3
+}
+
+// peek returns but does not consume the next token.
+func (t *Tree) peek() item {
+	if t.peekCount > 0 {
+		return t.token[t.peekCount-1]
+	}
+	t.peekCount = 1
+	t.token[0] = t.lex.nextItem()
+	return t.token[0]
+}
+
+// nextNonSpace returns the next non-space token.
+func (t *Tree) nextNonSpace() (token item) {
+	for {
+		token = t.next()
+		if token.typ != itemSpace {
+			break
+		}
+	}
+	return token
+}
+
+// peekNonSpace returns but does not consume the next non-space token.
+func (t *Tree) peekNonSpace() (token item) {
+	for {
+		token = t.next()
+		if token.typ != itemSpace {
+			break
+		}
+	}
+	t.backup()
+	return token
+}
+
+// Parsing.
+
+// New allocates a new parse tree with the given name.
+func New(name string, funcs ...map[string]interface{}) *Tree {
+	return &Tree{
+		Name:  name,
+		funcs: funcs,
+	}
+}
+
+// ErrorContext returns a textual representation of the location of the node in the input text.
+// The receiver is only used when the node does not have a pointer to the tree inside,
+// which can occur in old code.
+func (t *Tree) ErrorContext(n Node) (location, context string) {
+	pos := int(n.Position())
+	tree := n.tree()
+	if tree == nil {
+		tree = t
+	}
+	text := tree.text[:pos]
+	byteNum := strings.LastIndex(text, "\n")
+	if byteNum == -1 {
+		byteNum = pos // On first line.
+	} else {
+		byteNum++ // After the newline.
+		byteNum = pos - byteNum
+	}
+	lineNum := 1 + strings.Count(text, "\n")
+	context = n.String()
+	if len(context) > 20 {
+		context = fmt.Sprintf("%.20s...", context)
+	}
+	return fmt.Sprintf("%s:%d:%d", tree.ParseName, lineNum, byteNum), context
+}
+
+// errorf formats the error and terminates processing.
+func (t *Tree) errorf(format string, args ...interface{}) {
+	t.Root = nil
+	format = fmt.Sprintf("template: %s:%d: %s", t.ParseName, t.lex.lineNumber(), format)
+	panic(fmt.Errorf(format, args...))
+}
+
+// error terminates processing.
+func (t *Tree) error(err error) {
+	t.errorf("%s", err)
+}
+
+// expect consumes the next token and guarantees it has the required type.
+func (t *Tree) expect(expected itemType, context string) item {
+	token := t.nextNonSpace()
+	if token.typ != expected {
+		t.unexpected(token, context)
+	}
+	return token
+}
+
+// expectOneOf consumes the next token and guarantees it has one of the required types.
+func (t *Tree) expectOneOf(expected1, expected2 itemType, context string) item {
+	token := t.nextNonSpace()
+	if token.typ != expected1 && token.typ != expected2 {
+		t.unexpected(token, context)
+	}
+	return token
+}
+
+// unexpected complains about the token and terminates processing.
+func (t *Tree) unexpected(token item, context string) {
+	t.errorf("unexpected %s in %s", token, context)
+}
+
+// recover is the handler that turns panics into returns from the top level of Parse.
+func (t *Tree) recover(errp *error) {
+	e := recover()
+	if e != nil {
+		if _, ok := e.(runtime.Error); ok {
+			panic(e)
+		}
+		if t != nil {
+			t.stopParse()
+		}
+		*errp = e.(error)
+	}
+	return
+}
+
+// startParse initializes the parser, using the lexer.
+func (t *Tree) startParse(funcs []map[string]interface{}, lex *lexer) {
+	t.Root = nil
+	t.lex = lex
+	t.vars = []string{"$"}
+	t.funcs = funcs
+}
+
+// stopParse terminates parsing.
+func (t *Tree) stopParse() {
+	t.lex = nil
+	t.vars = nil
+	t.funcs = nil
+}
+
+// Parse parses the template definition string to construct a representation of
+// the template for execution. If either action delimiter string is empty, the
+// default ("{{" or "}}") is used. Embedded template definitions are added to
+// the treeSet map.
+func (t *Tree) Parse(text, leftDelim, rightDelim string, treeSet map[string]*Tree, funcs ...map[string]interface{}) (tree *Tree, err error) {
+	defer t.recover(&err)
+	t.ParseName = t.Name
+	t.startParse(funcs, lex(t.Name, text, leftDelim, rightDelim))
+	t.text = text
+	t.parse(treeSet)
+	t.add(treeSet)
+	t.stopParse()
+	return t, nil
+}
+
+// add adds tree to the treeSet.
+func (t *Tree) add(treeSet map[string]*Tree) {
+	tree := treeSet[t.Name]
+	if tree == nil || IsEmptyTree(tree.Root) {
+		treeSet[t.Name] = t
+		return
+	}
+	if !IsEmptyTree(t.Root) {
+		t.errorf("template: multiple definition of template %q", t.Name)
+	}
+}
+
+// IsEmptyTree reports whether this tree (node) is empty of everything but space.
+func IsEmptyTree(n Node) bool {
+	switch n := n.(type) {
+	case nil:
+		return true
+	case *ActionNode:
+	case *IfNode:
+	case *ListNode:
+		for _, node := range n.Nodes {
+			if !IsEmptyTree(node) {
+				return false
+			}
+		}
+		return true
+	case *RangeNode:
+	case *TemplateNode:
+	case *TextNode:
+		return len(bytes.TrimSpace(n.Text)) == 0
+	case *WithNode:
+	default:
+		panic("unknown node: " + n.String())
+	}
+	return false
+}
+
+// parse is the top-level parser for a template, essentially the same
+// as itemList except it also parses {{define}} actions.
+// It runs to EOF.
+func (t *Tree) parse(treeSet map[string]*Tree) (next Node) {
+	t.Root = t.newList(t.peek().pos)
+	for t.peek().typ != itemEOF {
+		if t.peek().typ == itemLeftDelim {
+			delim := t.next()
+			if t.nextNonSpace().typ == itemDefine {
+				newT := New("definition") // name will be updated once we know it.
+				newT.text = t.text
+				newT.ParseName = t.ParseName
+				newT.startParse(t.funcs, t.lex)
+				newT.parseDefinition(treeSet)
+				continue
+			}
+			t.backup2(delim)
+		}
+		n := t.textOrAction()
+		if n.Type() == nodeEnd {
+			t.errorf("unexpected %s", n)
+		}
+		t.Root.append(n)
+	}
+	return nil
+}
+
+// parseDefinition parses a {{define}} ...  {{end}} template definition and
+// installs the definition in the treeSet map.  The "define" keyword has already
+// been scanned.
+func (t *Tree) parseDefinition(treeSet map[string]*Tree) {
+	const context = "define clause"
+	name := t.expectOneOf(itemString, itemRawString, context)
+	var err error
+	t.Name, err = strconv.Unquote(name.val)
+	if err != nil {
+		t.error(err)
+	}
+	t.expect(itemRightDelim, context)
+	var end Node
+	t.Root, end = t.itemList()
+	if end.Type() != nodeEnd {
+		t.errorf("unexpected %s in %s", end, context)
+	}
+	t.add(treeSet)
+	t.stopParse()
+}
+
+// itemList:
+//	textOrAction*
+// Terminates at {{end}} or {{else}}, returned separately.
+func (t *Tree) itemList() (list *ListNode, next Node) {
+	list = t.newList(t.peekNonSpace().pos)
+	for t.peekNonSpace().typ != itemEOF {
+		n := t.textOrAction()
+		switch n.Type() {
+		case nodeEnd, nodeElse:
+			return list, n
+		}
+		list.append(n)
+	}
+	t.errorf("unexpected EOF")
+	return
+}
+
+// textOrAction:
+//	text | action
+func (t *Tree) textOrAction() Node {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemElideNewline:
+		return t.elideNewline()
+	case itemText:
+		return t.newText(token.pos, token.val)
+	case itemLeftDelim:
+		return t.action()
+	default:
+		t.unexpected(token, "input")
+	}
+	return nil
+}
+
+// elideNewline:
+// Remove newlines trailing rightDelim if \\ is present.
+func (t *Tree) elideNewline() Node {
+	token := t.peek()
+	if token.typ != itemText {
+		t.unexpected(token, "input")
+		return nil
+	}
+
+	t.next()
+	stripped := strings.TrimLeft(token.val, "\n\r")
+	diff := len(token.val) - len(stripped)
+	if diff > 0 {
+		// This is a bit nasty. We mutate the token in-place to remove
+		// preceding newlines.
+		token.pos += Pos(diff)
+		token.val = stripped
+	}
+	return t.newText(token.pos, token.val)
+}
+
+// Action:
+//	control
+//	command ("|" command)*
+// Left delim is past. Now get actions.
+// First word could be a keyword such as range.
+func (t *Tree) action() (n Node) {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemElse:
+		return t.elseControl()
+	case itemEnd:
+		return t.endControl()
+	case itemIf:
+		return t.ifControl()
+	case itemRange:
+		return t.rangeControl()
+	case itemTemplate:
+		return t.templateControl()
+	case itemWith:
+		return t.withControl()
+	}
+	t.backup()
+	// Do not pop variables; they persist until "end".
+	return t.newAction(t.peek().pos, t.lex.lineNumber(), t.pipeline("command"))
+}
+
+// Pipeline:
+//	declarations? command ('|' command)*
+func (t *Tree) pipeline(context string) (pipe *PipeNode) {
+	var decl []*VariableNode
+	pos := t.peekNonSpace().pos
+	// Are there declarations?
+	for {
+		if v := t.peekNonSpace(); v.typ == itemVariable {
+			t.next()
+			// Since space is a token, we need 3-token look-ahead here in the worst case:
+			// in "$x foo" we need to read "foo" (as opposed to ":=") to know that $x is an
+			// argument variable rather than a declaration. So remember the token
+			// adjacent to the variable so we can push it back if necessary.
+			tokenAfterVariable := t.peek()
+			if next := t.peekNonSpace(); next.typ == itemColonEquals || (next.typ == itemChar && next.val == ",") {
+				t.nextNonSpace()
+				variable := t.newVariable(v.pos, v.val)
+				decl = append(decl, variable)
+				t.vars = append(t.vars, v.val)
+				if next.typ == itemChar && next.val == "," {
+					if context == "range" && len(decl) < 2 {
+						continue
+					}
+					t.errorf("too many declarations in %s", context)
+				}
+			} else if tokenAfterVariable.typ == itemSpace {
+				t.backup3(v, tokenAfterVariable)
+			} else {
+				t.backup2(v)
+			}
+		}
+		break
+	}
+	pipe = t.newPipeline(pos, t.lex.lineNumber(), decl)
+	for {
+		switch token := t.nextNonSpace(); token.typ {
+		case itemRightDelim, itemRightParen:
+			if len(pipe.Cmds) == 0 {
+				t.errorf("missing value for %s", context)
+			}
+			if token.typ == itemRightParen {
+				t.backup()
+			}
+			return
+		case itemBool, itemCharConstant, itemComplex, itemDot, itemField, itemIdentifier,
+			itemNumber, itemNil, itemRawString, itemString, itemVariable, itemLeftParen:
+			t.backup()
+			pipe.append(t.command())
+		default:
+			t.unexpected(token, context)
+		}
+	}
+}
+
+func (t *Tree) parseControl(allowElseIf bool, context string) (pos Pos, line int, pipe *PipeNode, list, elseList *ListNode) {
+	defer t.popVars(len(t.vars))
+	line = t.lex.lineNumber()
+	pipe = t.pipeline(context)
+	var next Node
+	list, next = t.itemList()
+	switch next.Type() {
+	case nodeEnd: //done
+	case nodeElse:
+		if allowElseIf {
+			// Special case for "else if". If the "else" is followed immediately by an "if",
+			// the elseControl will have left the "if" token pending. Treat
+			//	{{if a}}_{{else if b}}_{{end}}
+			// as
+			//	{{if a}}_{{else}}{{if b}}_{{end}}{{end}}.
+			// To do this, parse the if as usual and stop at it {{end}}; the subsequent{{end}}
+			// is assumed. This technique works even for long if-else-if chains.
+			// TODO: Should we allow else-if in with and range?
+			if t.peek().typ == itemIf {
+				t.next() // Consume the "if" token.
+				elseList = t.newList(next.Position())
+				elseList.append(t.ifControl())
+				// Do not consume the next item - only one {{end}} required.
+				break
+			}
+		}
+		elseList, next = t.itemList()
+		if next.Type() != nodeEnd {
+			t.errorf("expected end; found %s", next)
+		}
+	}
+	return pipe.Position(), line, pipe, list, elseList
+}
+
+// If:
+//	{{if pipeline}} itemList {{end}}
+//	{{if pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Tree) ifControl() Node {
+	return t.newIf(t.parseControl(true, "if"))
+}
+
+// Range:
+//	{{range pipeline}} itemList {{end}}
+//	{{range pipeline}} itemList {{else}} itemList {{end}}
+// Range keyword is past.
+func (t *Tree) rangeControl() Node {
+	return t.newRange(t.parseControl(false, "range"))
+}
+
+// With:
+//	{{with pipeline}} itemList {{end}}
+//	{{with pipeline}} itemList {{else}} itemList {{end}}
+// If keyword is past.
+func (t *Tree) withControl() Node {
+	return t.newWith(t.parseControl(false, "with"))
+}
+
+// End:
+//	{{end}}
+// End keyword is past.
+func (t *Tree) endControl() Node {
+	return t.newEnd(t.expect(itemRightDelim, "end").pos)
+}
+
+// Else:
+//	{{else}}
+// Else keyword is past.
+func (t *Tree) elseControl() Node {
+	// Special case for "else if".
+	peek := t.peekNonSpace()
+	if peek.typ == itemIf {
+		// We see "{{else if ... " but in effect rewrite it to {{else}}{{if ... ".
+		return t.newElse(peek.pos, t.lex.lineNumber())
+	}
+	return t.newElse(t.expect(itemRightDelim, "else").pos, t.lex.lineNumber())
+}
+
+// Template:
+//	{{template stringValue pipeline}}
+// Template keyword is past.  The name must be something that can evaluate
+// to a string.
+func (t *Tree) templateControl() Node {
+	var name string
+	token := t.nextNonSpace()
+	switch token.typ {
+	case itemString, itemRawString:
+		s, err := strconv.Unquote(token.val)
+		if err != nil {
+			t.error(err)
+		}
+		name = s
+	default:
+		t.unexpected(token, "template invocation")
+	}
+	var pipe *PipeNode
+	if t.nextNonSpace().typ != itemRightDelim {
+		t.backup()
+		// Do not pop variables; they persist until "end".
+		pipe = t.pipeline("template")
+	}
+	return t.newTemplate(token.pos, t.lex.lineNumber(), name, pipe)
+}
+
+// command:
+//	operand (space operand)*
+// space-separated arguments up to a pipeline character or right delimiter.
+// we consume the pipe character but leave the right delim to terminate the action.
+func (t *Tree) command() *CommandNode {
+	cmd := t.newCommand(t.peekNonSpace().pos)
+	for {
+		t.peekNonSpace() // skip leading spaces.
+		operand := t.operand()
+		if operand != nil {
+			cmd.append(operand)
+		}
+		switch token := t.next(); token.typ {
+		case itemSpace:
+			continue
+		case itemError:
+			t.errorf("%s", token.val)
+		case itemRightDelim, itemRightParen:
+			t.backup()
+		case itemPipe:
+		default:
+			t.errorf("unexpected %s in operand; missing space?", token)
+		}
+		break
+	}
+	if len(cmd.Args) == 0 {
+		t.errorf("empty command")
+	}
+	return cmd
+}
+
+// operand:
+//	term .Field*
+// An operand is a space-separated component of a command,
+// a term possibly followed by field accesses.
+// A nil return means the next item is not an operand.
+func (t *Tree) operand() Node {
+	node := t.term()
+	if node == nil {
+		return nil
+	}
+	if t.peek().typ == itemField {
+		chain := t.newChain(t.peek().pos, node)
+		for t.peek().typ == itemField {
+			chain.Add(t.next().val)
+		}
+		// Compatibility with original API: If the term is of type NodeField
+		// or NodeVariable, just put more fields on the original.
+		// Otherwise, keep the Chain node.
+		// TODO: Switch to Chains always when we can.
+		switch node.Type() {
+		case NodeField:
+			node = t.newField(chain.Position(), chain.String())
+		case NodeVariable:
+			node = t.newVariable(chain.Position(), chain.String())
+		default:
+			node = chain
+		}
+	}
+	return node
+}
+
+// term:
+//	literal (number, string, nil, boolean)
+//	function (identifier)
+//	.
+//	.Field
+//	$
+//	'(' pipeline ')'
+// A term is a simple "expression".
+// A nil return means the next item is not a term.
+func (t *Tree) term() Node {
+	switch token := t.nextNonSpace(); token.typ {
+	case itemError:
+		t.errorf("%s", token.val)
+	case itemIdentifier:
+		if !t.hasFunction(token.val) {
+			t.errorf("function %q not defined", token.val)
+		}
+		return NewIdentifier(token.val).SetTree(t).SetPos(token.pos)
+	case itemDot:
+		return t.newDot(token.pos)
+	case itemNil:
+		return t.newNil(token.pos)
+	case itemVariable:
+		return t.useVar(token.pos, token.val)
+	case itemField:
+		return t.newField(token.pos, token.val)
+	case itemBool:
+		return t.newBool(token.pos, token.val == "true")
+	case itemCharConstant, itemComplex, itemNumber:
+		number, err := t.newNumber(token.pos, token.val, token.typ)
+		if err != nil {
+			t.error(err)
+		}
+		return number
+	case itemLeftParen:
+		pipe := t.pipeline("parenthesized pipeline")
+		if token := t.next(); token.typ != itemRightParen {
+			t.errorf("unclosed right paren: unexpected %s", token)
+		}
+		return pipe
+	case itemString, itemRawString:
+		s, err := strconv.Unquote(token.val)
+		if err != nil {
+			t.error(err)
+		}
+		return t.newString(token.pos, token.val, s)
+	}
+	t.backup()
+	return nil
+}
+
+// hasFunction reports if a function name exists in the Tree's maps.
+func (t *Tree) hasFunction(name string) bool {
+	for _, funcMap := range t.funcs {
+		if funcMap == nil {
+			continue
+		}
+		if funcMap[name] != nil {
+			return true
+		}
+	}
+	return false
+}
+
+// popVars trims the variable list to the specified length
+func (t *Tree) popVars(n int) {
+	t.vars = t.vars[:n]
+}
+
+// useVar returns a node for a variable reference. It errors if the
+// variable is not defined.
+func (t *Tree) useVar(pos Pos, name string) Node {
+	v := t.newVariable(pos, name)
+	for _, varName := range t.vars {
+		if varName == v.Ident[0] {
+			return v
+		}
+	}
+	t.errorf("undefined variable %q", v.Ident[0])
+	return nil
+}

vendor/github.com/alecthomas/template/template.go

@@ -0,0 +1,218 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package template
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/alecthomas/template/parse"
+)
+
+// common holds the information shared by related templates.
+type common struct {
+	tmpl map[string]*Template
+	// We use two maps, one for parsing and one for execution.
+	// This separation makes the API cleaner since it doesn't
+	// expose reflection to the client.
+	parseFuncs FuncMap
+	execFuncs  map[string]reflect.Value
+}
+
+// Template is the representation of a parsed template. The *parse.Tree
+// field is exported only for use by html/template and should be treated
+// as unexported by all other clients.
+type Template struct {
+	name string
+	*parse.Tree
+	*common
+	leftDelim  string
+	rightDelim string
+}
+
+// New allocates a new template with the given name.
+func New(name string) *Template {
+	return &Template{
+		name: name,
+	}
+}
+
+// Name returns the name of the template.
+func (t *Template) Name() string {
+	return t.name
+}
+
+// New allocates a new template associated with the given one and with the same
+// delimiters. The association, which is transitive, allows one template to
+// invoke another with a {{template}} action.
+func (t *Template) New(name string) *Template {
+	t.init()
+	return &Template{
+		name:       name,
+		common:     t.common,
+		leftDelim:  t.leftDelim,
+		rightDelim: t.rightDelim,
+	}
+}
+
+func (t *Template) init() {
+	if t.common == nil {
+		t.common = new(common)
+		t.tmpl = make(map[string]*Template)
+		t.parseFuncs = make(FuncMap)
+		t.execFuncs = make(map[string]reflect.Value)
+	}
+}
+
+// Clone returns a duplicate of the template, including all associated
+// templates. The actual representation is not copied, but the name space of
+// associated templates is, so further calls to Parse in the copy will add
+// templates to the copy but not to the original. Clone can be used to prepare
+// common templates and use them with variant definitions for other templates
+// by adding the variants after the clone is made.
+func (t *Template) Clone() (*Template, error) {
+	nt := t.copy(nil)
+	nt.init()
+	nt.tmpl[t.name] = nt
+	for k, v := range t.tmpl {
+		if k == t.name { // Already installed.
+			continue
+		}
+		// The associated templates share nt's common structure.
+		tmpl := v.copy(nt.common)
+		nt.tmpl[k] = tmpl
+	}
+	for k, v := range t.parseFuncs {
+		nt.parseFuncs[k] = v
+	}
+	for k, v := range t.execFuncs {
+		nt.execFuncs[k] = v
+	}
+	return nt, nil
+}
+
+// copy returns a shallow copy of t, with common set to the argument.
+func (t *Template) copy(c *common) *Template {
+	nt := New(t.name)
+	nt.Tree = t.Tree
+	nt.common = c
+	nt.leftDelim = t.leftDelim
+	nt.rightDelim = t.rightDelim
+	return nt
+}
+
+// AddParseTree creates a new template with the name and parse tree
+// and associates it with t.
+func (t *Template) AddParseTree(name string, tree *parse.Tree) (*Template, error) {
+	if t.common != nil && t.tmpl[name] != nil {
+		return nil, fmt.Errorf("template: redefinition of template %q", name)
+	}
+	nt := t.New(name)
+	nt.Tree = tree
+	t.tmpl[name] = nt
+	return nt, nil
+}
+
+// Templates returns a slice of the templates associated with t, including t
+// itself.
+func (t *Template) Templates() []*Template {
+	if t.common == nil {
+		return nil
+	}
+	// Return a slice so we don't expose the map.
+	m := make([]*Template, 0, len(t.tmpl))
+	for _, v := range t.tmpl {
+		m = append(m, v)
+	}
+	return m
+}
+
+// Delims sets the action delimiters to the specified strings, to be used in
+// subsequent calls to Parse, ParseFiles, or ParseGlob. Nested template
+// definitions will inherit the settings. An empty delimiter stands for the
+// corresponding default: {{ or }}.
+// The return value is the template, so calls can be chained.
+func (t *Template) Delims(left, right string) *Template {
+	t.leftDelim = left
+	t.rightDelim = right
+	return t
+}
+
+// Funcs adds the elements of the argument map to the template's function map.
+// It panics if a value in the map is not a function with appropriate return
+// type. However, it is legal to overwrite elements of the map. The return
+// value is the template, so calls can be chained.
+func (t *Template) Funcs(funcMap FuncMap) *Template {
+	t.init()
+	addValueFuncs(t.execFuncs, funcMap)
+	addFuncs(t.parseFuncs, funcMap)
+	return t
+}
+
+// Lookup returns the template with the given name that is associated with t,
+// or nil if there is no such template.
+func (t *Template) Lookup(name string) *Template {
+	if t.common == nil {
+		return nil
+	}
+	return t.tmpl[name]
+}
+
+// Parse parses a string into a template. Nested template definitions will be
+// associated with the top-level template t. Parse may be called multiple times
+// to parse definitions of templates to associate with t. It is an error if a
+// resulting template is non-empty (contains content other than template
+// definitions) and would replace a non-empty template with the same name.
+// (In multiple calls to Parse with the same receiver template, only one call
+// can contain text other than space, comments, and template definitions.)
+func (t *Template) Parse(text string) (*Template, error) {
+	t.init()
+	trees, err := parse.Parse(t.name, text, t.leftDelim, t.rightDelim, t.parseFuncs, builtins)
+	if err != nil {
+		return nil, err
+	}
+	// Add the newly parsed trees, including the one for t, into our common structure.
+	for name, tree := range trees {
+		// If the name we parsed is the name of this template, overwrite this template.
+		// The associate method checks it's not a redefinition.
+		tmpl := t
+		if name != t.name {
+			tmpl = t.New(name)
+		}
+		// Even if t == tmpl, we need to install it in the common.tmpl map.
+		if replace, err := t.associate(tmpl, tree); err != nil {
+			return nil, err
+		} else if replace {
+			tmpl.Tree = tree
+		}
+		tmpl.leftDelim = t.leftDelim
+		tmpl.rightDelim = t.rightDelim
+	}
+	return t, nil
+}
+
+// associate installs the new template into the group of templates associated
+// with t. It is an error to reuse a name except to overwrite an empty
+// template. The two are already known to share the common structure.
+// The boolean return value reports wither to store this tree as t.Tree.
+func (t *Template) associate(new *Template, tree *parse.Tree) (bool, error) {
+	if new.common != t.common {
+		panic("internal error: associate not common")
+	}
+	name := new.name
+	if old := t.tmpl[name]; old != nil {
+		oldIsEmpty := parse.IsEmptyTree(old.Root)
+		newIsEmpty := parse.IsEmptyTree(tree.Root)
+		if newIsEmpty {
+			// Whether old is empty or not, new is empty; no reason to replace old.
+			return false, nil
+		}
+		if !oldIsEmpty {
+			return false, fmt.Errorf("template: redefinition of template %q", name)
+		}
+	}
+	t.tmpl[name] = new
+	return true, nil
+}

vendor/github.com/alecthomas/units/COPYING

@@ -0,0 +1,19 @@
+Copyright (C) 2014 Alec Thomas
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/github.com/alecthomas/units/README.md

@@ -0,0 +1,11 @@
+# Units - Helpful unit multipliers and functions for Go
+
+The goal of this package is to have functionality similar to the [time](http://golang.org/pkg/time/) package.
+
+It allows for code like this:
+
+```go
+n, err := ParseBase2Bytes("1KB")
+// n == 1024
+n = units.Mebibyte * 512
+```

vendor/github.com/alecthomas/units/bytes.go

@@ -0,0 +1,83 @@
+package units
+
+// Base2Bytes is the old non-SI power-of-2 byte scale (1024 bytes in a kilobyte,
+// etc.).
+type Base2Bytes int64
+
+// Base-2 byte units.
+const (
+	Kibibyte Base2Bytes = 1024
+	KiB                 = Kibibyte
+	Mebibyte            = Kibibyte * 1024
+	MiB                 = Mebibyte
+	Gibibyte            = Mebibyte * 1024
+	GiB                 = Gibibyte
+	Tebibyte            = Gibibyte * 1024
+	TiB                 = Tebibyte
+	Pebibyte            = Tebibyte * 1024
+	PiB                 = Pebibyte
+	Exbibyte            = Pebibyte * 1024
+	EiB                 = Exbibyte
+)
+
+var (
+	bytesUnitMap    = MakeUnitMap("iB", "B", 1024)
+	oldBytesUnitMap = MakeUnitMap("B", "B", 1024)
+)
+
+// ParseBase2Bytes supports both iB and B in base-2 multipliers. That is, KB
+// and KiB are both 1024.
+func ParseBase2Bytes(s string) (Base2Bytes, error) {
+	n, err := ParseUnit(s, bytesUnitMap)
+	if err != nil {
+		n, err = ParseUnit(s, oldBytesUnitMap)
+	}
+	return Base2Bytes(n), err
+}
+
+func (b Base2Bytes) String() string {
+	return ToString(int64(b), 1024, "iB", "B")
+}
+
+var (
+	metricBytesUnitMap = MakeUnitMap("B", "B", 1000)
+)
+
+// MetricBytes are SI byte units (1000 bytes in a kilobyte).
+type MetricBytes SI
+
+// SI base-10 byte units.
+const (
+	Kilobyte MetricBytes = 1000
+	KB                   = Kilobyte
+	Megabyte             = Kilobyte * 1000
+	MB                   = Megabyte
+	Gigabyte             = Megabyte * 1000
+	GB                   = Gigabyte
+	Terabyte             = Gigabyte * 1000
+	TB                   = Terabyte
+	Petabyte             = Terabyte * 1000
+	PB                   = Petabyte
+	Exabyte              = Petabyte * 1000
+	EB                   = Exabyte
+)
+
+// ParseMetricBytes parses base-10 metric byte units. That is, KB is 1000 bytes.
+func ParseMetricBytes(s string) (MetricBytes, error) {
+	n, err := ParseUnit(s, metricBytesUnitMap)
+	return MetricBytes(n), err
+}
+
+func (m MetricBytes) String() string {
+	return ToString(int64(m), 1000, "B", "B")
+}
+
+// ParseStrictBytes supports both iB and B suffixes for base 2 and metric,
+// respectively. That is, KiB represents 1024 and KB represents 1000.
+func ParseStrictBytes(s string) (int64, error) {
+	n, err := ParseUnit(s, bytesUnitMap)
+	if err != nil {
+		n, err = ParseUnit(s, metricBytesUnitMap)
+	}
+	return int64(n), err
+}

vendor/github.com/alecthomas/units/doc.go

@@ -0,0 +1,13 @@
+// Package units provides helpful unit multipliers and functions for Go.
+//
+// The goal of this package is to have functionality similar to the time [1] package.
+//
+//
+// [1] http://golang.org/pkg/time/
+//
+// It allows for code like this:
+//
+//     n, err := ParseBase2Bytes("1KB")
+//     // n == 1024
+//     n = units.Mebibyte * 512
+package units

vendor/github.com/alecthomas/units/si.go

@@ -0,0 +1,26 @@
+package units
+
+// SI units.
+type SI int64
+
+// SI unit multiples.
+const (
+	Kilo SI = 1000
+	Mega    = Kilo * 1000
+	Giga    = Mega * 1000
+	Tera    = Giga * 1000
+	Peta    = Tera * 1000
+	Exa     = Peta * 1000
+)
+
+func MakeUnitMap(suffix, shortSuffix string, scale int64) map[string]float64 {
+	return map[string]float64{
+		shortSuffix:  1,
+		"K" + suffix: float64(scale),
+		"M" + suffix: float64(scale * scale),
+		"G" + suffix: float64(scale * scale * scale),
+		"T" + suffix: float64(scale * scale * scale * scale),
+		"P" + suffix: float64(scale * scale * scale * scale * scale),
+		"E" + suffix: float64(scale * scale * scale * scale * scale * scale),
+	}
+}

vendor/github.com/alecthomas/units/util.go

@@ -0,0 +1,138 @@
+package units
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+var (
+	siUnits = []string{"", "K", "M", "G", "T", "P", "E"}
+)
+
+func ToString(n int64, scale int64, suffix, baseSuffix string) string {
+	mn := len(siUnits)
+	out := make([]string, mn)
+	for i, m := range siUnits {
+		if n%scale != 0 || i == 0 && n == 0 {
+			s := suffix
+			if i == 0 {
+				s = baseSuffix
+			}
+			out[mn-1-i] = fmt.Sprintf("%d%s%s", n%scale, m, s)
+		}
+		n /= scale
+		if n == 0 {
+			break
+		}
+	}
+	return strings.Join(out, "")
+}
+
+// Below code ripped straight from http://golang.org/src/pkg/time/format.go?s=33392:33438#L1123
+var errLeadingInt = errors.New("units: bad [0-9]*") // never printed
+
+// leadingInt consumes the leading [0-9]* from s.
+func leadingInt(s string) (x int64, rem string, err error) {
+	i := 0
+	for ; i < len(s); i++ {
+		c := s[i]
+		if c < '0' || c > '9' {
+			break
+		}
+		if x >= (1<<63-10)/10 {
+			// overflow
+			return 0, "", errLeadingInt
+		}
+		x = x*10 + int64(c) - '0'
+	}
+	return x, s[i:], nil
+}
+
+func ParseUnit(s string, unitMap map[string]float64) (int64, error) {
+	// [-+]?([0-9]*(\.[0-9]*)?[a-z]+)+
+	orig := s
+	f := float64(0)
+	neg := false
+
+	// Consume [-+]?
+	if s != "" {
+		c := s[0]
+		if c == '-' || c == '+' {
+			neg = c == '-'
+			s = s[1:]
+		}
+	}
+	// Special case: if all that is left is "0", this is zero.
+	if s == "0" {
+		return 0, nil
+	}
+	if s == "" {
+		return 0, errors.New("units: invalid " + orig)
+	}
+	for s != "" {
+		g := float64(0) // this element of the sequence
+
+		var x int64
+		var err error
+
+		// The next character must be [0-9.]
+		if !(s[0] == '.' || ('0' <= s[0] && s[0] <= '9')) {
+			return 0, errors.New("units: invalid " + orig)
+		}
+		// Consume [0-9]*
+		pl := len(s)
+		x, s, err = leadingInt(s)
+		if err != nil {
+			return 0, errors.New("units: invalid " + orig)
+		}
+		g = float64(x)
+		pre := pl != len(s) // whether we consumed anything before a period
+
+		// Consume (\.[0-9]*)?
+		post := false
+		if s != "" && s[0] == '.' {
+			s = s[1:]
+			pl := len(s)
+			x, s, err = leadingInt(s)
+			if err != nil {
+				return 0, errors.New("units: invalid " + orig)
+			}
+			scale := 1.0
+			for n := pl - len(s); n > 0; n-- {
+				scale *= 10
+			}
+			g += float64(x) / scale
+			post = pl != len(s)
+		}
+		if !pre && !post {
+			// no digits (e.g. ".s" or "-.s")
+			return 0, errors.New("units: invalid " + orig)
+		}
+
+		// Consume unit.
+		i := 0
+		for ; i < len(s); i++ {
+			c := s[i]
+			if c == '.' || ('0' <= c && c <= '9') {
+				break
+			}
+		}
+		u := s[:i]
+		s = s[i:]
+		unit, ok := unitMap[u]
+		if !ok {
+			return 0, errors.New("units: unknown unit " + u + " in " + orig)
+		}
+
+		f += g * unit
+	}
+
+	if neg {
+		f = -f
+	}
+	if f < float64(-1<<63) || f > float64(1<<63-1) {
+		return 0, errors.New("units: overflow parsing unit")
+	}
+	return int64(f), nil
+}

vendor/github.com/prometheus/common/expfmt/decode.go

@@ -31,6 +31,7 @@ type Decoder interface {
 	Decode(*dto.MetricFamily) error
 }
 
+// DecodeOptions contains options used by the Decoder and in sample extraction.
 type DecodeOptions struct {
 	// Timestamp is added to each value from the stream that has no explicit timestamp set.
 	Timestamp model.Time
@@ -46,10 +47,7 @@ func ResponseFormat(h http.Header) Format {
 		return FmtUnknown
 	}
 
-	const (
+	const textType = "text/plain"
-		textType = "text/plain"
-		jsonType = "application/json"
-	)
 
 	switch mediatype {
 	case ProtoType:
@@ -66,22 +64,6 @@ func ResponseFormat(h http.Header) Format {
 			return FmtUnknown
 		}
 		return FmtText
-
-	case jsonType:
-		var prometheusAPIVersion string
-
-		if params["schema"] == "prometheus/telemetry" && params["version"] != "" {
-			prometheusAPIVersion = params["version"]
-		} else {
-			prometheusAPIVersion = h.Get("X-Prometheus-API-Version")
-		}
-
-		switch prometheusAPIVersion {
-		case "0.0.2", "":
-			return fmtJSON2
-		default:
-			return FmtUnknown
-		}
 	}
 
 	return FmtUnknown
@@ -93,8 +75,6 @@ func NewDecoder(r io.Reader, format Format) Decoder {
 	switch format {
 	case FmtProtoDelim:
 		return &protoDecoder{r: r}
-	case fmtJSON2:
-		return newJSON2Decoder(r)
 	}
 	return &textDecoder{r: r}
 }
@@ -132,7 +112,7 @@ func (d *protoDecoder) Decode(v *dto.MetricFamily) error {
 	return nil
 }
 
-// textDecoder implements the Decoder interface for the text protcol.
+// textDecoder implements the Decoder interface for the text protocol.
 type textDecoder struct {
 	r    io.Reader
 	p    TextParser
@@ -163,6 +143,8 @@ func (d *textDecoder) Decode(v *dto.MetricFamily) error {
 	return nil
 }
 
+// SampleDecoder wraps a Decoder to extract samples from the metric families
+// decoded by the wrapped Decoder.
 type SampleDecoder struct {
 	Dec  Decoder
 	Opts *DecodeOptions
@@ -170,37 +152,51 @@ type SampleDecoder struct {
 	f dto.MetricFamily
 }
 
+// Decode calls the Decode method of the wrapped Decoder and then extracts the
+// samples from the decoded MetricFamily into the provided model.Vector.
 func (sd *SampleDecoder) Decode(s *model.Vector) error {
-	if err := sd.Dec.Decode(&sd.f); err != nil {
+	err := sd.Dec.Decode(&sd.f)
+	if err != nil {
 		return err
 	}
-	*s = extractSamples(&sd.f, sd.Opts)
+	*s, err = extractSamples(&sd.f, sd.Opts)
-	return nil
+	return err
 }
 
-// Extract samples builds a slice of samples from the provided metric families.
+// ExtractSamples builds a slice of samples from the provided metric
-func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) model.Vector {
+// families. If an error occurs during sample extraction, it continues to
-	var all model.Vector
+// extract from the remaining metric families. The returned error is the last
+// error that has occured.
+func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) (model.Vector, error) {
+	var (
+		all     model.Vector
+		lastErr error
+	)
 	for _, f := range fams {
-		all = append(all, extractSamples(f, o)...)
+		some, err := extractSamples(f, o)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		all = append(all, some...)
 	}
-	return all
+	return all, lastErr
 }
 
-func extractSamples(f *dto.MetricFamily, o *DecodeOptions) model.Vector {
+func extractSamples(f *dto.MetricFamily, o *DecodeOptions) (model.Vector, error) {
 	switch f.GetType() {
 	case dto.MetricType_COUNTER:
-		return extractCounter(o, f)
+		return extractCounter(o, f), nil
 	case dto.MetricType_GAUGE:
-		return extractGauge(o, f)
+		return extractGauge(o, f), nil
 	case dto.MetricType_SUMMARY:
-		return extractSummary(o, f)
+		return extractSummary(o, f), nil
 	case dto.MetricType_UNTYPED:
-		return extractUntyped(o, f)
+		return extractUntyped(o, f), nil
 	case dto.MetricType_HISTOGRAM:
-		return extractHistogram(o, f)
+		return extractHistogram(o, f), nil
 	}
-	panic("expfmt.extractSamples: unknown metric family type")
+	return nil, fmt.Errorf("expfmt.extractSamples: unknown metric family type %v", f.GetType())
 }
 
 func extractCounter(o *DecodeOptions, f *dto.MetricFamily) model.Vector {

vendor/github.com/prometheus/common/expfmt/expfmt.go

@@ -11,14 +11,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// A package for reading and writing Prometheus metrics.
+// Package expfmt contains tools for reading and writing Prometheus metrics.
 package expfmt
 
+// Format specifies the HTTP content type of the different wire protocols.
 type Format string
 
+// Constants to assemble the Content-Type values for the different wire protocols.
 const (
-	TextVersion = "0.0.4"
+	TextVersion   = "0.0.4"
-
 	ProtoType     = `application/vnd.google.protobuf`
 	ProtoProtocol = `io.prometheus.client.MetricFamily`
 	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
@@ -29,9 +30,6 @@ const (
 	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
 	FmtProtoText    Format = ProtoFmt + ` encoding=text`
 	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
-
-	// fmtJSON2 is hidden as it is deprecated.
-	fmtJSON2 Format = `application/json; version=0.0.2`
 )
 
 const (

vendor/github.com/prometheus/common/expfmt/fuzz.go

@@ -20,8 +20,8 @@ import "bytes"
 
 // Fuzz text metric parser with with github.com/dvyukov/go-fuzz:
 //
-//     go-fuzz-build github.com/prometheus/client_golang/text
+//     go-fuzz-build github.com/prometheus/common/expfmt
-//     go-fuzz -bin text-fuzz.zip -workdir fuzz
+//     go-fuzz -bin expfmt-fuzz.zip -workdir fuzz
 //
 // Further input samples should go in the folder fuzz/corpus.
 func Fuzz(in []byte) int {

vendor/github.com/prometheus/common/expfmt/json_decode.go

@@ -1,174 +0,0 @@
-// Copyright 2015 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package expfmt
-
-import (
-	"encoding/json"
-	"fmt"
-	"io"
-	"sort"
-
-	"github.com/golang/protobuf/proto"
-	dto "github.com/prometheus/client_model/go"
-
-	"github.com/prometheus/common/model"
-)
-
-type json2Decoder struct {
-	dec  *json.Decoder
-	fams []*dto.MetricFamily
-}
-
-func newJSON2Decoder(r io.Reader) Decoder {
-	return &json2Decoder{
-		dec: json.NewDecoder(r),
-	}
-}
-
-type histogram002 struct {
-	Labels model.LabelSet     `json:"labels"`
-	Values map[string]float64 `json:"value"`
-}
-
-type counter002 struct {
-	Labels model.LabelSet `json:"labels"`
-	Value  float64        `json:"value"`
-}
-
-func protoLabelSet(base, ext model.LabelSet) ([]*dto.LabelPair, error) {
-	labels := base.Clone().Merge(ext)
-	delete(labels, model.MetricNameLabel)
-
-	names := make([]string, 0, len(labels))
-	for ln := range labels {
-		names = append(names, string(ln))
-	}
-	sort.Strings(names)
-
-	pairs := make([]*dto.LabelPair, 0, len(labels))
-
-	for _, ln := range names {
-		if !model.LabelNameRE.MatchString(ln) {
-			return nil, fmt.Errorf("invalid label name %q", ln)
-		}
-		lv := labels[model.LabelName(ln)]
-
-		pairs = append(pairs, &dto.LabelPair{
-			Name:  proto.String(ln),
-			Value: proto.String(string(lv)),
-		})
-	}
-
-	return pairs, nil
-}
-
-func (d *json2Decoder) more() error {
-	var entities []struct {
-		BaseLabels model.LabelSet `json:"baseLabels"`
-		Docstring  string         `json:"docstring"`
-		Metric     struct {
-			Type   string          `json:"type"`
-			Values json.RawMessage `json:"value"`
-		} `json:"metric"`
-	}
-
-	if err := d.dec.Decode(&entities); err != nil {
-		return err
-	}
-	for _, e := range entities {
-		f := &dto.MetricFamily{
-			Name:   proto.String(string(e.BaseLabels[model.MetricNameLabel])),
-			Help:   proto.String(e.Docstring),
-			Type:   dto.MetricType_UNTYPED.Enum(),
-			Metric: []*dto.Metric{},
-		}
-
-		d.fams = append(d.fams, f)
-
-		switch e.Metric.Type {
-		case "counter", "gauge":
-			var values []counter002
-
-			if err := json.Unmarshal(e.Metric.Values, &values); err != nil {
-				return fmt.Errorf("could not extract %s value: %s", e.Metric.Type, err)
-			}
-
-			for _, ctr := range values {
-				labels, err := protoLabelSet(e.BaseLabels, ctr.Labels)
-				if err != nil {
-					return err
-				}
-				f.Metric = append(f.Metric, &dto.Metric{
-					Label: labels,
-					Untyped: &dto.Untyped{
-						Value: proto.Float64(ctr.Value),
-					},
-				})
-			}
-
-		case "histogram":
-			var values []histogram002
-
-			if err := json.Unmarshal(e.Metric.Values, &values); err != nil {
-				return fmt.Errorf("could not extract %s value: %s", e.Metric.Type, err)
-			}
-
-			for _, hist := range values {
-				quants := make([]string, 0, len(values))
-				for q := range hist.Values {
-					quants = append(quants, q)
-				}
-
-				sort.Strings(quants)
-
-				for _, q := range quants {
-					value := hist.Values[q]
-					// The correct label is "quantile" but to not break old expressions
-					// this remains "percentile"
-					hist.Labels["percentile"] = model.LabelValue(q)
-
-					labels, err := protoLabelSet(e.BaseLabels, hist.Labels)
-					if err != nil {
-						return err
-					}
-
-					f.Metric = append(f.Metric, &dto.Metric{
-						Label: labels,
-						Untyped: &dto.Untyped{
-							Value: proto.Float64(value),
-						},
-					})
-				}
-			}
-
-		default:
-			return fmt.Errorf("unknown metric type %q", e.Metric.Type)
-		}
-	}
-	return nil
-}
-
-// Decode implements the Decoder interface.
-func (d *json2Decoder) Decode(v *dto.MetricFamily) error {
-	if len(d.fams) == 0 {
-		if err := d.more(); err != nil {
-			return err
-		}
-	}
-
-	*v = *d.fams[0]
-	d.fams = d.fams[1:]
-
-	return nil
-}

vendor/github.com/prometheus/common/expfmt/text_create.go

@@ -14,7 +14,6 @@
 package expfmt
 
 import (
-	"bytes"
 	"fmt"
 	"io"
 	"math"
@@ -26,9 +25,12 @@ import (
 
 // MetricFamilyToText converts a MetricFamily proto message into text format and
 // writes the resulting lines to 'out'. It returns the number of bytes written
-// and any error encountered.  This function does not perform checks on the
+// and any error encountered. The output will have the same order as the input,
-// content of the metric and label names, i.e. invalid metric or label names
+// no further sorting is performed. Furthermore, this function assumes the input
+// is already sanitized and does not perform any sanity checks. If the input
+// contains duplicate metrics or invalid metric or label names, the conversion
 // will result in invalid text format output.
+//
 // This method fulfills the type 'prometheus.encoder'.
 func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
 	var written int
@@ -285,21 +287,17 @@ func labelPairsToText(
 	return written, nil
 }
 
+var (
+	escape                = strings.NewReplacer("\\", `\\`, "\n", `\n`)
+	escapeWithDoubleQuote = strings.NewReplacer("\\", `\\`, "\n", `\n`, "\"", `\"`)
+)
+
 // escapeString replaces '\' by '\\', new line character by '\n', and - if
 // includeDoubleQuote is true - '"' by '\"'.
 func escapeString(v string, includeDoubleQuote bool) string {
-	result := bytes.NewBuffer(make([]byte, 0, len(v)))
+	if includeDoubleQuote {
-	for _, c := range v {
+		return escapeWithDoubleQuote.Replace(v)
-		switch {
-		case c == '\\':
-			result.WriteString(`\\`)
-		case includeDoubleQuote && c == '"':
-			result.WriteString(`\"`)
-		case c == '\n':
-			result.WriteString(`\n`)
-		default:
-			result.WriteRune(c)
-		}
 	}
-	return result.String()
+
+	return escape.Replace(v)
 }

vendor/github.com/prometheus/common/expfmt/text_parse.go

@@ -47,7 +47,7 @@ func (e ParseError) Error() string {
 }
 
 // TextParser is used to parse the simple and flat text-based exchange format. Its
-// nil value is ready to use.
+// zero value is ready to use.
 type TextParser struct {
 	metricFamiliesByName map[string]*dto.MetricFamily
 	buf                  *bufio.Reader // Where the parsed input is read through.
@@ -315,6 +315,10 @@ func (p *TextParser) startLabelValue() stateFn {
 	if p.readTokenAsLabelValue(); p.err != nil {
 		return nil
 	}
+	if !model.LabelValue(p.currentToken.String()).IsValid() {
+		p.parseError(fmt.Sprintf("invalid label value %q", p.currentToken.String()))
+		return nil
+	}
 	p.currentLabelPair.Value = proto.String(p.currentToken.String())
 	// Special treatment of summaries:
 	// - Quantile labels are special, will result in dto.Quantile later.

vendor/github.com/prometheus/common/log/eventlog_formatter.go

@@ -0,0 +1,89 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build windows
+
+package log
+
+import (
+	"fmt"
+	"os"
+
+	"golang.org/x/sys/windows/svc/eventlog"
+
+	"github.com/sirupsen/logrus"
+)
+
+func init() {
+	setEventlogFormatter = func(l logger, name string, debugAsInfo bool) error {
+		if name == "" {
+			return fmt.Errorf("missing name parameter")
+		}
+
+		fmter, err := newEventlogger(name, debugAsInfo, l.entry.Logger.Formatter)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "error creating eventlog formatter: %v\n", err)
+			l.Errorf("can't connect logger to eventlog: %v", err)
+			return err
+		}
+		l.entry.Logger.Formatter = fmter
+		return nil
+	}
+}
+
+type eventlogger struct {
+	log         *eventlog.Log
+	debugAsInfo bool
+	wrap        logrus.Formatter
+}
+
+func newEventlogger(name string, debugAsInfo bool, fmter logrus.Formatter) (*eventlogger, error) {
+	logHandle, err := eventlog.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	return &eventlogger{log: logHandle, debugAsInfo: debugAsInfo, wrap: fmter}, nil
+}
+
+func (s *eventlogger) Format(e *logrus.Entry) ([]byte, error) {
+	data, err := s.wrap.Format(e)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "eventlogger: can't format entry: %v\n", err)
+		return data, err
+	}
+
+	switch e.Level {
+	case logrus.PanicLevel:
+		fallthrough
+	case logrus.FatalLevel:
+		fallthrough
+	case logrus.ErrorLevel:
+		err = s.log.Error(102, e.Message)
+	case logrus.WarnLevel:
+		err = s.log.Warning(101, e.Message)
+	case logrus.InfoLevel:
+		err = s.log.Info(100, e.Message)
+	case logrus.DebugLevel:
+		if s.debugAsInfo {
+			err = s.log.Info(100, e.Message)
+		}
+	default:
+		err = s.log.Info(100, e.Message)
+	}
+
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "eventlogger: can't send log to eventlog: %v\n", err)
+	}
+
+	return data, err
+}

vendor/github.com/prometheus/common/log/log.go

@@ -14,88 +14,59 @@
 package log
 
 import (
-	"flag"
 	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
 	"net/url"
 	"os"
 	"runtime"
+	"strconv"
 	"strings"
 
-	"github.com/Sirupsen/logrus"
+	"github.com/sirupsen/logrus"
+	"gopkg.in/alecthomas/kingpin.v2"
 )
 
-type levelFlag struct{}
-
-// String implements flag.Value.
-func (f levelFlag) String() string {
-	return origLogger.Level.String()
-}
-
-// Set implements flag.Value.
-func (f levelFlag) Set(level string) error {
-	l, err := logrus.ParseLevel(level)
-	if err != nil {
-		return err
-	}
-	origLogger.Level = l
-	return nil
-}
-
 // setSyslogFormatter is nil if the target architecture does not support syslog.
-var setSyslogFormatter func(string, string) error
+var setSyslogFormatter func(logger, string, string) error
+
+// setEventlogFormatter is nil if the target OS does not support Eventlog (i.e., is not Windows).
+var setEventlogFormatter func(logger, string, bool) error
 
 func setJSONFormatter() {
 	origLogger.Formatter = &logrus.JSONFormatter{}
 }
 
-type logFormatFlag struct{ uri string }
+type loggerSettings struct {
-
+	level  string
-// String implements flag.Value.
+	format string
-func (f logFormatFlag) String() string {
-	return f.uri
 }
 
-// Set implements flag.Value.
+func (s *loggerSettings) apply(ctx *kingpin.ParseContext) error {
-func (f logFormatFlag) Set(format string) error {
+	err := baseLogger.SetLevel(s.level)
-	f.uri = format
-	u, err := url.Parse(format)
 	if err != nil {
 		return err
 	}
-	if u.Scheme != "logger" {
+	err = baseLogger.SetFormat(s.format)
-		return fmt.Errorf("invalid scheme %s", u.Scheme)
+	return err
-	}
-	jsonq := u.Query().Get("json")
-	if jsonq == "true" {
-		setJSONFormatter()
-	}
-
-	switch u.Opaque {
-	case "syslog":
-		if setSyslogFormatter == nil {
-			return fmt.Errorf("system does not support syslog")
-		}
-		appname := u.Query().Get("appname")
-		facility := u.Query().Get("local")
-		return setSyslogFormatter(appname, facility)
-	case "stdout":
-		origLogger.Out = os.Stdout
-	case "stderr":
-		origLogger.Out = os.Stderr
-
-	default:
-		return fmt.Errorf("unsupported logger %s", u.Opaque)
-	}
-	return nil
 }
 
-func init() {
+// AddFlags adds the flags used by this package to the Kingpin application.
-	// In order for these flags to take effect, the user of the package must call
+// To use the default Kingpin application, call AddFlags(kingpin.CommandLine)
-	// flag.Parse() before logging anything.
+func AddFlags(a *kingpin.Application) {
-	flag.Var(levelFlag{}, "log.level", "Only log messages with the given severity or above. Valid levels: [debug, info, warn, error, fatal].")
+	s := loggerSettings{}
-	flag.Var(logFormatFlag{}, "log.format", "If set use a syslog logger or JSON logging. Example: logger:syslog?appname=bob&local=7 or logger:stdout?json=true. Defaults to stderr.")
+	kingpin.Flag("log.level", "Only log messages with the given severity or above. Valid levels: [debug, info, warn, error, fatal]").
+		Default(origLogger.Level.String()).
+		StringVar(&s.level)
+	defaultFormat := url.URL{Scheme: "logger", Opaque: "stderr"}
+	kingpin.Flag("log.format", `Set the log target and format. Example: "logger:syslog?appname=bob&local=7" or "logger:stdout?json=true"`).
+		Default(defaultFormat.String()).
+		StringVar(&s.format)
+	a.Action(s.apply)
 }
 
+// Logger is the interface for loggers used in the Prometheus components.
 type Logger interface {
 	Debug(...interface{})
 	Debugln(...interface{})
@@ -118,6 +89,9 @@ type Logger interface {
 	Fatalf(string, ...interface{})
 
 	With(key string, value interface{}) Logger
+
+	SetFormat(string) error
+	SetLevel(string) error
 }
 
 type logger struct {
@@ -203,6 +177,58 @@ func (l logger) Fatalf(format string, args ...interface{}) {
 	l.sourced().Fatalf(format, args...)
 }
 
+func (l logger) SetLevel(level string) error {
+	lvl, err := logrus.ParseLevel(level)
+	if err != nil {
+		return err
+	}
+
+	l.entry.Logger.Level = lvl
+	return nil
+}
+
+func (l logger) SetFormat(format string) error {
+	u, err := url.Parse(format)
+	if err != nil {
+		return err
+	}
+	if u.Scheme != "logger" {
+		return fmt.Errorf("invalid scheme %s", u.Scheme)
+	}
+	jsonq := u.Query().Get("json")
+	if jsonq == "true" {
+		setJSONFormatter()
+	}
+
+	switch u.Opaque {
+	case "syslog":
+		if setSyslogFormatter == nil {
+			return fmt.Errorf("system does not support syslog")
+		}
+		appname := u.Query().Get("appname")
+		facility := u.Query().Get("local")
+		return setSyslogFormatter(l, appname, facility)
+	case "eventlog":
+		if setEventlogFormatter == nil {
+			return fmt.Errorf("system does not support eventlog")
+		}
+		name := u.Query().Get("name")
+		debugAsInfo := false
+		debugAsInfoRaw := u.Query().Get("debugAsInfo")
+		if parsedDebugAsInfo, err := strconv.ParseBool(debugAsInfoRaw); err == nil {
+			debugAsInfo = parsedDebugAsInfo
+		}
+		return setEventlogFormatter(l, name, debugAsInfo)
+	case "stdout":
+		l.entry.Logger.Out = os.Stdout
+	case "stderr":
+		l.entry.Logger.Out = os.Stderr
+	default:
+		return fmt.Errorf("unsupported logger %q", u.Opaque)
+	}
+	return nil
+}
+
 // sourced adds a source field to the logger that contains
 // the file name and line where the logging happened.
 func (l logger) sourced() *logrus.Entry {
@@ -220,10 +246,26 @@ func (l logger) sourced() *logrus.Entry {
 var origLogger = logrus.New()
 var baseLogger = logger{entry: logrus.NewEntry(origLogger)}
 
+// Base returns the default Logger logging to
 func Base() Logger {
 	return baseLogger
 }
 
+// NewLogger returns a new Logger logging to out.
+func NewLogger(w io.Writer) Logger {
+	l := logrus.New()
+	l.Out = w
+	return logger{entry: logrus.NewEntry(l)}
+}
+
+// NewNopLogger returns a logger that discards all log messages.
+func NewNopLogger() Logger {
+	l := logrus.New()
+	l.Out = ioutil.Discard
+	return logger{entry: logrus.NewEntry(l)}
+}
+
+// With adds a field to the logger.
 func With(key string, value interface{}) Logger {
 	return baseLogger.With(key, value)
 }
@@ -233,7 +275,7 @@ func Debug(args ...interface{}) {
 	baseLogger.sourced().Debug(args...)
 }
 
-// Debug logs a message at level Debug on the standard logger.
+// Debugln logs a message at level Debug on the standard logger.
 func Debugln(args ...interface{}) {
 	baseLogger.sourced().Debugln(args...)
 }
@@ -248,7 +290,7 @@ func Info(args ...interface{}) {
 	baseLogger.sourced().Info(args...)
 }
 
-// Info logs a message at level Info on the standard logger.
+// Infoln logs a message at level Info on the standard logger.
 func Infoln(args ...interface{}) {
 	baseLogger.sourced().Infoln(args...)
 }
@@ -263,7 +305,7 @@ func Warn(args ...interface{}) {
 	baseLogger.sourced().Warn(args...)
 }
 
-// Warn logs a message at level Warn on the standard logger.
+// Warnln logs a message at level Warn on the standard logger.
 func Warnln(args ...interface{}) {
 	baseLogger.sourced().Warnln(args...)
 }
@@ -278,7 +320,7 @@ func Error(args ...interface{}) {
 	baseLogger.sourced().Error(args...)
 }
 
-// Error logs a message at level Error on the standard logger.
+// Errorln logs a message at level Error on the standard logger.
 func Errorln(args ...interface{}) {
 	baseLogger.sourced().Errorln(args...)
 }
@@ -293,7 +335,7 @@ func Fatal(args ...interface{}) {
 	baseLogger.sourced().Fatal(args...)
 }
 
-// Fatal logs a message at level Fatal on the standard logger.
+// Fatalln logs a message at level Fatal on the standard logger.
 func Fatalln(args ...interface{}) {
 	baseLogger.sourced().Fatalln(args...)
 }
@@ -302,3 +344,16 @@ func Fatalln(args ...interface{}) {
 func Fatalf(format string, args ...interface{}) {
 	baseLogger.sourced().Fatalf(format, args...)
 }
+
+type errorLogWriter struct{}
+
+func (errorLogWriter) Write(b []byte) (int, error) {
+	baseLogger.sourced().Error(string(b))
+	return len(b), nil
+}
+
+// NewErrorLogger returns a log.Logger that is meant to be used
+// in the ErrorLog field of an http.Server to log HTTP server errors.
+func NewErrorLogger() *log.Logger {
+	return log.New(&errorLogWriter{}, "", 0)
+}

vendor/github.com/prometheus/common/log/syslog_formatter.go

@@ -20,11 +20,13 @@ import (
 	"log/syslog"
 	"os"
 
-	"github.com/Sirupsen/logrus"
+	"github.com/sirupsen/logrus"
 )
 
+var _ logrus.Formatter = (*syslogger)(nil)
+
 func init() {
-	setSyslogFormatter = func(appname, local string) error {
+	setSyslogFormatter = func(l logger, appname, local string) error {
 		if appname == "" {
 			return fmt.Errorf("missing appname parameter")
 		}
@@ -32,18 +34,18 @@ func init() {
 			return fmt.Errorf("missing local parameter")
 		}
 
-		fmter, err := newSyslogger(appname, local, origLogger.Formatter)
+		fmter, err := newSyslogger(appname, local, l.entry.Logger.Formatter)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "error creating syslog formatter: %v\n", err)
-			origLogger.Errorf("can't connect logger to syslog: %v", err)
+			l.entry.Errorf("can't connect logger to syslog: %v", err)
 			return err
 		}
-		origLogger.Formatter = fmter
+		l.entry.Logger.Formatter = fmter
 		return nil
 	}
 }
 
-var ceeTag = []byte("@cee:")
+var prefixTag []byte
 
 type syslogger struct {
 	wrap logrus.Formatter
@@ -56,6 +58,11 @@ func newSyslogger(appname string, facility string, fmter logrus.Formatter) (*sys
 		return nil, err
 	}
 	out, err := syslog.New(priority, appname)
+	_, isJSON := fmter.(*logrus.JSONFormatter)
+	if isJSON {
+		// add cee tag to json formatted syslogs
+		prefixTag = []byte("@cee:")
+	}
 	return &syslogger{
 		out:  out,
 		wrap: fmter,
@@ -92,7 +99,7 @@ func (s *syslogger) Format(e *logrus.Entry) ([]byte, error) {
 	}
 	// only append tag to data sent to syslog (line), not to what
 	// is returned
-	line := string(append(ceeTag, data...))
+	line := string(append(prefixTag, data...))
 
 	switch e.Level {
 	case logrus.PanicLevel:

vendor/github.com/prometheus/common/model/labels.go

@@ -80,14 +80,18 @@ const (
 	QuantileLabel = "quantile"
 )
 
-// LabelNameRE is a regular expression matching valid label names.
+// LabelNameRE is a regular expression matching valid label names. Note that the
+// IsValid method of LabelName performs the same check but faster than a match
+// with this regular expression.
 var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
 
 // A LabelName is a key for a LabelSet or Metric.  It has a value associated
 // therewith.
 type LabelName string
 
-// IsValid is true iff the label name matches the pattern of LabelNameRE.
+// IsValid is true iff the label name matches the pattern of LabelNameRE. This
+// method, however, does not use LabelNameRE for the check but a much faster
+// hardcoded implementation.
 func (ln LabelName) IsValid() bool {
 	if len(ln) == 0 {
 		return false
@@ -106,7 +110,7 @@ func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	if err := unmarshal(&s); err != nil {
 		return err
 	}
-	if !LabelNameRE.MatchString(s) {
+	if !LabelName(s).IsValid() {
 		return fmt.Errorf("%q is not a valid label name", s)
 	}
 	*ln = LabelName(s)
@@ -119,7 +123,7 @@ func (ln *LabelName) UnmarshalJSON(b []byte) error {
 	if err := json.Unmarshal(b, &s); err != nil {
 		return err
 	}
-	if !LabelNameRE.MatchString(s) {
+	if !LabelName(s).IsValid() {
 		return fmt.Errorf("%q is not a valid label name", s)
 	}
 	*ln = LabelName(s)

vendor/github.com/prometheus/common/model/labelset.go

@@ -160,7 +160,7 @@ func (l *LabelSet) UnmarshalJSON(b []byte) error {
 	// LabelName as a string and does not call its UnmarshalJSON method.
 	// Thus, we have to replicate the behavior here.
 	for ln := range m {
-		if !LabelNameRE.MatchString(string(ln)) {
+		if !ln.IsValid() {
 			return fmt.Errorf("%q is not a valid label name", ln)
 		}
 	}

vendor/github.com/prometheus/common/model/metric.go

@@ -21,8 +21,11 @@ import (
 )
 
 var (
-	separator    = []byte{0}
+	separator = []byte{0}
-	MetricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
+	// MetricNameRE is a regular expression matching valid metric
+	// names. Note that the IsValidMetricName function performs the same
+	// check but faster than a match with this regular expression.
+	MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
 )
 
 // A Metric is similar to a LabelSet, but the key difference is that a Metric is
@@ -41,7 +44,7 @@ func (m Metric) Before(o Metric) bool {
 
 // Clone returns a copy of the Metric.
 func (m Metric) Clone() Metric {
-	clone := Metric{}
+	clone := make(Metric, len(m))
 	for k, v := range m {
 		clone[k] = v
 	}
@@ -85,6 +88,8 @@ func (m Metric) FastFingerprint() Fingerprint {
 }
 
 // IsValidMetricName returns true iff name matches the pattern of MetricNameRE.
+// This function, however, does not use MetricNameRE for the check but a much
+// faster hardcoded implementation.
 func IsValidMetricName(n LabelValue) bool {
 	if len(n) == 0 {
 		return false

vendor/github.com/prometheus/common/model/model.go

@@ -12,5 +12,5 @@
 // limitations under the License.
 
 // Package model contains common data structures that are shared across
-// Prometheus componenets and libraries.
+// Prometheus components and libraries.
 package model

vendor/github.com/prometheus/common/model/time.go

@@ -163,9 +163,21 @@ func (t *Time) UnmarshalJSON(b []byte) error {
 // This type should not propagate beyond the scope of input/output processing.
 type Duration time.Duration
 
+// Set implements pflag/flag.Value
+func (d *Duration) Set(s string) error {
+	var err error
+	*d, err = ParseDuration(s)
+	return err
+}
+
+// Type implements pflag.Value
+func (d *Duration) Type() string {
+	return "duration"
+}
+
 var durationRE = regexp.MustCompile("^([0-9]+)(y|w|d|h|m|s|ms)$")
 
-// StringToDuration parses a string into a time.Duration, assuming that a year
+// ParseDuration parses a string into a time.Duration, assuming that a year
 // always has 365d, a week always has 7d, and a day always has 24h.
 func ParseDuration(durationStr string) (Duration, error) {
 	matches := durationRE.FindStringSubmatch(durationStr)

vendor/github.com/prometheus/common/model/value.go

@@ -16,11 +16,28 @@ package model
 import (
 	"encoding/json"
 	"fmt"
+	"math"
 	"sort"
 	"strconv"
 	"strings"
 )
 
+var (
+	// ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
+	// non-existing sample pair. It is a SamplePair with timestamp Earliest and
+	// value 0.0. Note that the natural zero value of SamplePair has a timestamp
+	// of 0, which is possible to appear in a real SamplePair and thus not
+	// suitable to signal a non-existing SamplePair.
+	ZeroSamplePair = SamplePair{Timestamp: Earliest}
+
+	// ZeroSample is the pseudo zero-value of Sample used to signal a
+	// non-existing sample. It is a Sample with timestamp Earliest, value 0.0,
+	// and metric nil. Note that the natural zero value of Sample has a timestamp
+	// of 0, which is possible to appear in a real Sample and thus not suitable
+	// to signal a non-existing Sample.
+	ZeroSample = Sample{Timestamp: Earliest}
+)
+
 // A SampleValue is a representation of a value for a given sample at a given
 // time.
 type SampleValue float64
@@ -43,8 +60,14 @@ func (v *SampleValue) UnmarshalJSON(b []byte) error {
 	return nil
 }
 
+// Equal returns true if the value of v and o is equal or if both are NaN. Note
+// that v==o is false if both are NaN. If you want the conventional float
+// behavior, use == to compare two SampleValues.
 func (v SampleValue) Equal(o SampleValue) bool {
-	return v == o
+	if v == o {
+		return true
+	}
+	return math.IsNaN(float64(v)) && math.IsNaN(float64(o))
 }
 
 func (v SampleValue) String() string {
@@ -77,9 +100,9 @@ func (s *SamplePair) UnmarshalJSON(b []byte) error {
 }
 
 // Equal returns true if this SamplePair and o have equal Values and equal
-// Timestamps.
+// Timestamps. The sematics of Value equality is defined by SampleValue.Equal.
 func (s *SamplePair) Equal(o *SamplePair) bool {
-	return s == o || (s.Value == o.Value && s.Timestamp.Equal(o.Timestamp))
+	return s == o || (s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp))
 }
 
 func (s SamplePair) String() string {
@@ -93,7 +116,8 @@ type Sample struct {
 	Timestamp Time        `json:"timestamp"`
 }
 
-// Equal compares first the metrics, then the timestamp, then the value.
+// Equal compares first the metrics, then the timestamp, then the value. The
+// sematics of value equality is defined by SampleValue.Equal.
 func (s *Sample) Equal(o *Sample) bool {
 	if s == o {
 		return true
@@ -105,11 +129,8 @@ func (s *Sample) Equal(o *Sample) bool {
 	if !s.Timestamp.Equal(o.Timestamp) {
 		return false
 	}
-	if s.Value != o.Value {
-		return false
-	}
 
-	return true
+	return s.Value.Equal(o.Value)
 }
 
 func (s Sample) String() string {

vendor/github.com/sirupsen/logrus/CHANGELOG.md

@@ -0,0 +1,113 @@
+# 1.0.3
+
+* Replace example files with testable examples
+
+# 1.0.2
+
+* bug: quote non-string values in text formatter (#583)
+* Make (*Logger) SetLevel a public method
+
+# 1.0.1
+
+* bug: fix escaping in text formatter (#575)
+
+# 1.0.0
+
+* Officially changed name to lower-case
+* bug: colors on Windows 10 (#541)
+* bug: fix race in accessing level (#512)
+
+# 0.11.5
+
+* feature: add writer and writerlevel to entry (#372)
+
+# 0.11.4
+
+* bug: fix undefined variable on solaris (#493)
+
+# 0.11.3
+
+* formatter: configure quoting of empty values (#484)
+* formatter: configure quoting character (default is `"`) (#484)
+* bug: fix not importing io correctly in non-linux environments (#481)
+
+# 0.11.2
+
+* bug: fix windows terminal detection (#476)
+
+# 0.11.1
+
+* bug: fix tty detection with custom out (#471)
+
+# 0.11.0
+
+* performance: Use bufferpool to allocate (#370)
+* terminal: terminal detection for app-engine (#343)
+* feature: exit handler (#375)
+
+# 0.10.0
+
+* feature: Add a test hook (#180)
+* feature: `ParseLevel` is now case-insensitive (#326)
+* feature: `FieldLogger` interface that generalizes `Logger` and `Entry` (#308)
+* performance: avoid re-allocations on `WithFields` (#335)
+
+# 0.9.0
+
+* logrus/text_formatter: don't emit empty msg
+* logrus/hooks/airbrake: move out of main repository
+* logrus/hooks/sentry: move out of main repository
+* logrus/hooks/papertrail: move out of main repository
+* logrus/hooks/bugsnag: move out of main repository
+* logrus/core: run tests with `-race`
+* logrus/core: detect TTY based on `stderr`
+* logrus/core: support `WithError` on logger
+* logrus/core: Solaris support
+
+# 0.8.7
+
+* logrus/core: fix possible race (#216)
+* logrus/doc: small typo fixes and doc improvements
+
+
+# 0.8.6
+
+* hooks/raven: allow passing an initialized client
+
+# 0.8.5
+
+* logrus/core: revert #208
+
+# 0.8.4
+
+* formatter/text: fix data race (#218)
+
+# 0.8.3
+
+* logrus/core: fix entry log level (#208)
+* logrus/core: improve performance of text formatter by 40%
+* logrus/core: expose `LevelHooks` type
+* logrus/core: add support for DragonflyBSD and NetBSD
+* formatter/text: print structs more verbosely
+
+# 0.8.2
+
+* logrus: fix more Fatal family functions
+
+# 0.8.1
+
+* logrus: fix not exiting on `Fatalf` and `Fatalln`
+
+# 0.8.0
+
+* logrus: defaults to stderr instead of stdout
+* hooks/sentry: add special field for `*http.Request`
+* formatter/text: ignore Windows for colors
+
+# 0.7.3
+
+* formatter/\*: allow configuration of timestamp layout
+
+# 0.7.2
+
+* formatter/text: Add configuration option for time format (#158)

vendor/github.com/sirupsen/logrus/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Simon Eskildsen
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

vendor/github.com/sirupsen/logrus/README.md

@@ -0,0 +1,507 @@
+# Logrus <img src="http://i.imgur.com/hTeVwmJ.png" width="40" height="40" alt=":walrus:" class="emoji" title=":walrus:"/>&nbsp;[![Build Status](https://travis-ci.org/sirupsen/logrus.svg?branch=master)](https://travis-ci.org/sirupsen/logrus)&nbsp;[![GoDoc](https://godoc.org/github.com/sirupsen/logrus?status.svg)](https://godoc.org/github.com/sirupsen/logrus)
+
+Logrus is a structured logger for Go (golang), completely API compatible with
+the standard library logger.
+
+**Seeing weird case-sensitive problems?** It's in the past been possible to
+import Logrus as both upper- and lower-case. Due to the Go package environment,
+this caused issues in the community and we needed a standard. Some environments
+experienced problems with the upper-case variant, so the lower-case was decided.
+Everything using `logrus` will need to use the lower-case:
+`github.com/sirupsen/logrus`. Any package that isn't, should be changed.
+
+To fix Glide, see [these
+comments](https://github.com/sirupsen/logrus/issues/553#issuecomment-306591437).
+For an in-depth explanation of the casing issue, see [this
+comment](https://github.com/sirupsen/logrus/issues/570#issuecomment-313933276).
+
+**Are you interested in assisting in maintaining Logrus?** Currently I have a
+lot of obligations, and I am unable to provide Logrus with the maintainership it
+needs. If you'd like to help, please reach out to me at `simon at author's
+username dot com`.
+
+Nicely color-coded in development (when a TTY is attached, otherwise just
+plain text):
+
+![Colored](http://i.imgur.com/PY7qMwd.png)
+
+With `log.SetFormatter(&log.JSONFormatter{})`, for easy parsing by logstash
+or Splunk:
+
+```json
+{"animal":"walrus","level":"info","msg":"A group of walrus emerges from the
+ocean","size":10,"time":"2014-03-10 19:57:38.562264131 -0400 EDT"}
+
+{"level":"warning","msg":"The group's number increased tremendously!",
+"number":122,"omg":true,"time":"2014-03-10 19:57:38.562471297 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"A giant walrus appears!",
+"size":10,"time":"2014-03-10 19:57:38.562500591 -0400 EDT"}
+
+{"animal":"walrus","level":"info","msg":"Tremendously sized cow enters the ocean.",
+"size":9,"time":"2014-03-10 19:57:38.562527896 -0400 EDT"}
+
+{"level":"fatal","msg":"The ice breaks!","number":100,"omg":true,
+"time":"2014-03-10 19:57:38.562543128 -0400 EDT"}
+```
+
+With the default `log.SetFormatter(&log.TextFormatter{})` when a TTY is not
+attached, the output is compatible with the
+[logfmt](http://godoc.org/github.com/kr/logfmt) format:
+
+```text
+time="2015-03-26T01:27:38-04:00" level=debug msg="Started observing beach" animal=walrus number=8
+time="2015-03-26T01:27:38-04:00" level=info msg="A group of walrus emerges from the ocean" animal=walrus size=10
+time="2015-03-26T01:27:38-04:00" level=warning msg="The group's number increased tremendously!" number=122 omg=true
+time="2015-03-26T01:27:38-04:00" level=debug msg="Temperature changes" temperature=-4
+time="2015-03-26T01:27:38-04:00" level=panic msg="It's over 9000!" animal=orca size=9009
+time="2015-03-26T01:27:38-04:00" level=fatal msg="The ice breaks!" err=&{0x2082280c0 map[animal:orca size:9009] 2015-03-26 01:27:38.441574009 -0400 EDT panic It's over 9000!} number=100 omg=true
+exit status 1
+```
+
+#### Case-sensitivity
+
+The organization's name was changed to lower-case--and this will not be changed
+back. If you are getting import conflicts due to case sensitivity, please use
+the lower-case import: `github.com/sirupsen/logrus`.
+
+#### Example
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+```go
+package main
+
+import (
+  log "github.com/sirupsen/logrus"
+)
+
+func main() {
+  log.WithFields(log.Fields{
+    "animal": "walrus",
+  }).Info("A walrus appears")
+}
+```
+
+Note that it's completely api-compatible with the stdlib logger, so you can
+replace your `log` imports everywhere with `log "github.com/sirupsen/logrus"`
+and you'll now have the flexibility of Logrus. You can customize it all you
+want:
+
+```go
+package main
+
+import (
+  "os"
+  log "github.com/sirupsen/logrus"
+)
+
+func init() {
+  // Log as JSON instead of the default ASCII formatter.
+  log.SetFormatter(&log.JSONFormatter{})
+
+  // Output to stdout instead of the default stderr
+  // Can be any io.Writer, see below for File example
+  log.SetOutput(os.Stdout)
+
+  // Only log the warning severity or above.
+  log.SetLevel(log.WarnLevel)
+}
+
+func main() {
+  log.WithFields(log.Fields{
+    "animal": "walrus",
+    "size":   10,
+  }).Info("A group of walrus emerges from the ocean")
+
+  log.WithFields(log.Fields{
+    "omg":    true,
+    "number": 122,
+  }).Warn("The group's number increased tremendously!")
+
+  log.WithFields(log.Fields{
+    "omg":    true,
+    "number": 100,
+  }).Fatal("The ice breaks!")
+
+  // A common pattern is to re-use fields between logging statements by re-using
+  // the logrus.Entry returned from WithFields()
+  contextLogger := log.WithFields(log.Fields{
+    "common": "this is a common field",
+    "other": "I also should be logged always",
+  })
+
+  contextLogger.Info("I'll be logged with common and other field")
+  contextLogger.Info("Me too")
+}
+```
+
+For more advanced usage such as logging to multiple locations from the same
+application, you can also create an instance of the `logrus` Logger:
+
+```go
+package main
+
+import (
+  "os"
+  "github.com/sirupsen/logrus"
+)
+
+// Create a new instance of the logger. You can have any number of instances.
+var log = logrus.New()
+
+func main() {
+  // The API for setting attributes is a little different than the package level
+  // exported logger. See Godoc.
+  log.Out = os.Stdout
+
+  // You could set this to any `io.Writer` such as a file
+  // file, err := os.OpenFile("logrus.log", os.O_CREATE|os.O_WRONLY, 0666)
+  // if err == nil {
+  //  log.Out = file
+  // } else {
+  //  log.Info("Failed to log to file, using default stderr")
+  // }
+
+  log.WithFields(logrus.Fields{
+    "animal": "walrus",
+    "size":   10,
+  }).Info("A group of walrus emerges from the ocean")
+}
+```
+
+#### Fields
+
+Logrus encourages careful, structured logging through logging fields instead of
+long, unparseable error messages. For example, instead of: `log.Fatalf("Failed
+to send event %s to topic %s with key %d")`, you should log the much more
+discoverable:
+
+```go
+log.WithFields(log.Fields{
+  "event": event,
+  "topic": topic,
+  "key": key,
+}).Fatal("Failed to send event")
+```
+
+We've found this API forces you to think about logging in a way that produces
+much more useful logging messages. We've been in countless situations where just
+a single added field to a log statement that was already there would've saved us
+hours. The `WithFields` call is optional.
+
+In general, with Logrus using any of the `printf`-family functions should be
+seen as a hint you should add a field, however, you can still use the
+`printf`-family functions with Logrus.
+
+#### Default Fields
+
+Often it's helpful to have fields _always_ attached to log statements in an
+application or parts of one. For example, you may want to always log the
+`request_id` and `user_ip` in the context of a request. Instead of writing
+`log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})` on
+every line, you can create a `logrus.Entry` to pass around instead:
+
+```go
+requestLogger := log.WithFields(log.Fields{"request_id": request_id, "user_ip": user_ip})
+requestLogger.Info("something happened on that request") # will log request_id and user_ip
+requestLogger.Warn("something not great happened")
+```
+
+#### Hooks
+
+You can add hooks for logging levels. For example to send errors to an exception
+tracking service on `Error`, `Fatal` and `Panic`, info to StatsD or log to
+multiple places simultaneously, e.g. syslog.
+
+Logrus comes with [built-in hooks](hooks/). Add those, or your custom hook, in
+`init`:
+
+```go
+import (
+  log "github.com/sirupsen/logrus"
+  "gopkg.in/gemnasium/logrus-airbrake-hook.v2" // the package is named "aibrake"
+  logrus_syslog "github.com/sirupsen/logrus/hooks/syslog"
+  "log/syslog"
+)
+
+func init() {
+
+  // Use the Airbrake hook to report errors that have Error severity or above to
+  // an exception tracker. You can create custom hooks, see the Hooks section.
+  log.AddHook(airbrake.NewHook(123, "xyz", "production"))
+
+  hook, err := logrus_syslog.NewSyslogHook("udp", "localhost:514", syslog.LOG_INFO, "")
+  if err != nil {
+    log.Error("Unable to connect to local syslog daemon")
+  } else {
+    log.AddHook(hook)
+  }
+}
+```
+Note: Syslog hook also support connecting to local syslog (Ex. "/dev/log" or "/var/run/syslog" or "/var/run/log"). For the detail, please check the [syslog hook README](hooks/syslog/README.md).
+
+| Hook  | Description |
+| ----- | ----------- |
+| [Airbrake "legacy"](https://github.com/gemnasium/logrus-airbrake-legacy-hook) | Send errors to an exception tracking service compatible with the Airbrake API V2. Uses [`airbrake-go`](https://github.com/tobi/airbrake-go) behind the scenes. |
+| [Airbrake](https://github.com/gemnasium/logrus-airbrake-hook) | Send errors to the Airbrake API V3. Uses the official [`gobrake`](https://github.com/airbrake/gobrake) behind the scenes. |
+| [Amazon Kinesis](https://github.com/evalphobia/logrus_kinesis) | Hook for logging to [Amazon Kinesis](https://aws.amazon.com/kinesis/) |
+| [Amqp-Hook](https://github.com/vladoatanasov/logrus_amqp) | Hook for logging to Amqp broker (Like RabbitMQ) |
+| [AzureTableHook](https://github.com/kpfaulkner/azuretablehook/) | Hook for logging to Azure Table Storage|
+| [Bugsnag](https://github.com/Shopify/logrus-bugsnag/blob/master/bugsnag.go) | Send errors to the Bugsnag exception tracking service. |
+| [DeferPanic](https://github.com/deferpanic/dp-logrus) | Hook for logging to DeferPanic |
+| [Discordrus](https://github.com/kz/discordrus) | Hook for logging to [Discord](https://discordapp.com/) |
+| [ElasticSearch](https://github.com/sohlich/elogrus) | Hook for logging to ElasticSearch|
+| [Firehose](https://github.com/beaubrewer/logrus_firehose) | Hook for logging to [Amazon Firehose](https://aws.amazon.com/kinesis/firehose/)
+| [Fluentd](https://github.com/evalphobia/logrus_fluent) | Hook for logging to fluentd |
+| [Go-Slack](https://github.com/multiplay/go-slack) | Hook for logging to [Slack](https://slack.com) |
+| [Graylog](https://github.com/gemnasium/logrus-graylog-hook) | Hook for logging to [Graylog](http://graylog2.org/) |
+| [Hiprus](https://github.com/nubo/hiprus) | Send errors to a channel in hipchat. |
+| [Honeybadger](https://github.com/agonzalezro/logrus_honeybadger) | Hook for sending exceptions to Honeybadger |
+| [InfluxDB](https://github.com/Abramovic/logrus_influxdb) | Hook for logging to influxdb |
+| [Influxus](http://github.com/vlad-doru/influxus) | Hook for concurrently logging to [InfluxDB](http://influxdata.com/) |
+| [Journalhook](https://github.com/wercker/journalhook) | Hook for logging to `systemd-journald` |
+| [KafkaLogrus](https://github.com/tracer0tong/kafkalogrus) | Hook for logging to Kafka |
+| [LFShook](https://github.com/rifflock/lfshook) | Hook for logging to the local filesystem |
+| [Logentries](https://github.com/jcftang/logentriesrus) | Hook for logging to [Logentries](https://logentries.com/) |
+| [Logentrus](https://github.com/puddingfactory/logentrus) | Hook for logging to [Logentries](https://logentries.com/) |
+| [Logmatic.io](https://github.com/logmatic/logmatic-go) | Hook for logging to [Logmatic.io](http://logmatic.io/) |
+| [Logrusly](https://github.com/sebest/logrusly) | Send logs to [Loggly](https://www.loggly.com/) |
+| [Logstash](https://github.com/bshuster-repo/logrus-logstash-hook) | Hook for logging to [Logstash](https://www.elastic.co/products/logstash) |
+| [Mail](https://github.com/zbindenren/logrus_mail) | Hook for sending exceptions via mail |
+| [Mattermost](https://github.com/shuLhan/mattermost-integration/tree/master/hooks/logrus) | Hook for logging to [Mattermost](https://mattermost.com/) |
+| [Mongodb](https://github.com/weekface/mgorus) | Hook for logging to mongodb |
+| [NATS-Hook](https://github.com/rybit/nats_logrus_hook) | Hook for logging to [NATS](https://nats.io) |
+| [Octokit](https://github.com/dorajistyle/logrus-octokit-hook) | Hook for logging to github via octokit |
+| [Papertrail](https://github.com/polds/logrus-papertrail-hook) | Send errors to the [Papertrail](https://papertrailapp.com) hosted logging service via UDP. |
+| [PostgreSQL](https://github.com/gemnasium/logrus-postgresql-hook) | Send logs to [PostgreSQL](http://postgresql.org) |
+| [Pushover](https://github.com/toorop/logrus_pushover) | Send error via [Pushover](https://pushover.net) |
+| [Raygun](https://github.com/squirkle/logrus-raygun-hook) | Hook for logging to [Raygun.io](http://raygun.io/) |
+| [Redis-Hook](https://github.com/rogierlommers/logrus-redis-hook) | Hook for logging to a ELK stack (through Redis) |
+| [Rollrus](https://github.com/heroku/rollrus) | Hook for sending errors to rollbar |
+| [Scribe](https://github.com/sagar8192/logrus-scribe-hook) | Hook for logging to [Scribe](https://github.com/facebookarchive/scribe)|
+| [Sentry](https://github.com/evalphobia/logrus_sentry) | Send errors to the Sentry error logging and aggregation service. |
+| [Slackrus](https://github.com/johntdyer/slackrus) | Hook for Slack chat. |
+| [Stackdriver](https://github.com/knq/sdhook) | Hook for logging to [Google Stackdriver](https://cloud.google.com/logging/) |
+| [Sumorus](https://github.com/doublefree/sumorus) | Hook for logging to [SumoLogic](https://www.sumologic.com/)|
+| [Syslog](https://github.com/sirupsen/logrus/blob/master/hooks/syslog/syslog.go) | Send errors to remote syslog server. Uses standard library `log/syslog` behind the scenes. |
+| [Syslog TLS](https://github.com/shinji62/logrus-syslog-ng) | Send errors to remote syslog server with TLS support. |
+| [Telegram](https://github.com/rossmcdonald/telegram_hook) | Hook for logging errors to [Telegram](https://telegram.org/) |
+| [TraceView](https://github.com/evalphobia/logrus_appneta) | Hook for logging to [AppNeta TraceView](https://www.appneta.com/products/traceview/) |
+| [Typetalk](https://github.com/dragon3/logrus-typetalk-hook) | Hook for logging to [Typetalk](https://www.typetalk.in/) |
+| [logz.io](https://github.com/ripcurld00d/logrus-logzio-hook) | Hook for logging to [logz.io](https://logz.io), a Log as a Service using Logstash |
+| [SQS-Hook](https://github.com/tsarpaul/logrus_sqs) | Hook for logging to [Amazon Simple Queue Service (SQS)](https://aws.amazon.com/sqs/) |
+
+#### Level logging
+
+Logrus has six logging levels: Debug, Info, Warning, Error, Fatal and Panic.
+
+```go
+log.Debug("Useful debugging information.")
+log.Info("Something noteworthy happened!")
+log.Warn("You should probably take a look at this.")
+log.Error("Something failed but I'm not quitting.")
+// Calls os.Exit(1) after logging
+log.Fatal("Bye.")
+// Calls panic() after logging
+log.Panic("I'm bailing.")
+```
+
+You can set the logging level on a `Logger`, then it will only log entries with
+that severity or anything above it:
+
+```go
+// Will log anything that is info or above (warn, error, fatal, panic). Default.
+log.SetLevel(log.InfoLevel)
+```
+
+It may be useful to set `log.Level = logrus.DebugLevel` in a debug or verbose
+environment if your application has that.
+
+#### Entries
+
+Besides the fields added with `WithField` or `WithFields` some fields are
+automatically added to all logging events:
+
+1. `time`. The timestamp when the entry was created.
+2. `msg`. The logging message passed to `{Info,Warn,Error,Fatal,Panic}` after
+   the `AddFields` call. E.g. `Failed to send event.`
+3. `level`. The logging level. E.g. `info`.
+
+#### Environments
+
+Logrus has no notion of environment.
+
+If you wish for hooks and formatters to only be used in specific environments,
+you should handle that yourself. For example, if your application has a global
+variable `Environment`, which is a string representation of the environment you
+could do:
+
+```go
+import (
+  log "github.com/sirupsen/logrus"
+)
+
+init() {
+  // do something here to set environment depending on an environment variable
+  // or command-line flag
+  if Environment == "production" {
+    log.SetFormatter(&log.JSONFormatter{})
+  } else {
+    // The TextFormatter is default, you don't actually have to do this.
+    log.SetFormatter(&log.TextFormatter{})
+  }
+}
+```
+
+This configuration is how `logrus` was intended to be used, but JSON in
+production is mostly only useful if you do log aggregation with tools like
+Splunk or Logstash.
+
+#### Formatters
+
+The built-in logging formatters are:
+
+* `logrus.TextFormatter`. Logs the event in colors if stdout is a tty, otherwise
+  without colors.
+  * *Note:* to force colored output when there is no TTY, set the `ForceColors`
+    field to `true`.  To force no colored output even if there is a TTY  set the
+    `DisableColors` field to `true`. For Windows, see
+    [github.com/mattn/go-colorable](https://github.com/mattn/go-colorable).
+  * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#TextFormatter).
+* `logrus.JSONFormatter`. Logs fields as JSON.
+  * All options are listed in the [generated docs](https://godoc.org/github.com/sirupsen/logrus#JSONFormatter).
+
+Third party logging formatters:
+
+* [`FluentdFormatter`](https://github.com/joonix/log). Formats entries that can by parsed by Kubernetes and Google Container Engine.
+* [`logstash`](https://github.com/bshuster-repo/logrus-logstash-hook). Logs fields as [Logstash](http://logstash.net) Events.
+* [`prefixed`](https://github.com/x-cray/logrus-prefixed-formatter). Displays log entry source along with alternative layout.
+* [`zalgo`](https://github.com/aybabtme/logzalgo). Invoking the P͉̫o̳̼̊w̖͈̰͎e̬͔̭͂r͚̼̹̲ ̫͓͉̳͈ō̠͕͖̚f̝͍̠ ͕̲̞͖͑Z̖̫̤̫ͪa͉̬͈̗l͖͎g̳̥o̰̥̅!̣͔̲̻͊̄ ̙̘̦̹̦.
+
+You can define your formatter by implementing the `Formatter` interface,
+requiring a `Format` method. `Format` takes an `*Entry`. `entry.Data` is a
+`Fields` type (`map[string]interface{}`) with all your fields as well as the
+default ones (see Entries section above):
+
+```go
+type MyJSONFormatter struct {
+}
+
+log.SetFormatter(new(MyJSONFormatter))
+
+func (f *MyJSONFormatter) Format(entry *Entry) ([]byte, error) {
+  // Note this doesn't include Time, Level and Message which are available on
+  // the Entry. Consult `godoc` on information about those fields or read the
+  // source of the official loggers.
+  serialized, err := json.Marshal(entry.Data)
+    if err != nil {
+      return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+    }
+  return append(serialized, '\n'), nil
+}
+```
+
+#### Logger as an `io.Writer`
+
+Logrus can be transformed into an `io.Writer`. That writer is the end of an `io.Pipe` and it is your responsibility to close it.
+
+```go
+w := logger.Writer()
+defer w.Close()
+
+srv := http.Server{
+    // create a stdlib log.Logger that writes to
+    // logrus.Logger.
+    ErrorLog: log.New(w, "", 0),
+}
+```
+
+Each line written to that writer will be printed the usual way, using formatters
+and hooks. The level for those entries is `info`.
+
+This means that we can override the standard library logger easily:
+
+```go
+logger := logrus.New()
+logger.Formatter = &logrus.JSONFormatter{}
+
+// Use logrus for standard log output
+// Note that `log` here references stdlib's log
+// Not logrus imported under the name `log`.
+log.SetOutput(logger.Writer())
+```
+
+#### Rotation
+
+Log rotation is not provided with Logrus. Log rotation should be done by an
+external program (like `logrotate(8)`) that can compress and delete old log
+entries. It should not be a feature of the application-level logger.
+
+#### Tools
+
+| Tool | Description |
+| ---- | ----------- |
+|[Logrus Mate](https://github.com/gogap/logrus_mate)|Logrus mate is a tool for Logrus to manage loggers, you can initial logger's level, hook and formatter by config file, the logger will generated with different config at different environment.|
+|[Logrus Viper Helper](https://github.com/heirko/go-contrib/tree/master/logrusHelper)|An Helper around Logrus to wrap with spf13/Viper to load configuration with fangs! And to simplify Logrus configuration use some behavior of [Logrus Mate](https://github.com/gogap/logrus_mate). [sample](https://github.com/heirko/iris-contrib/blob/master/middleware/logrus-logger/example) |
+
+#### Testing
+
+Logrus has a built in facility for asserting the presence of log messages. This is implemented through the `test` hook and provides:
+
+* decorators for existing logger (`test.NewLocal` and `test.NewGlobal`) which basically just add the `test` hook
+* a test logger (`test.NewNullLogger`) that just records log messages (and does not output any):
+
+```go
+import(
+  "github.com/sirupsen/logrus"
+  "github.com/sirupsen/logrus/hooks/test"
+  "github.com/stretchr/testify/assert"
+  "testing"
+)
+
+func TestSomething(t*testing.T){
+  logger, hook := test.NewNullLogger()
+  logger.Error("Helloerror")
+
+  assert.Equal(t, 1, len(hook.Entries))
+  assert.Equal(t, logrus.ErrorLevel, hook.LastEntry().Level)
+  assert.Equal(t, "Helloerror", hook.LastEntry().Message)
+
+  hook.Reset()
+  assert.Nil(t, hook.LastEntry())
+}
+```
+
+#### Fatal handlers
+
+Logrus can register one or more functions that will be called when any `fatal`
+level message is logged. The registered handlers will be executed before
+logrus performs a `os.Exit(1)`. This behavior may be helpful if callers need
+to gracefully shutdown. Unlike a `panic("Something went wrong...")` call which can be intercepted with a deferred `recover` a call to `os.Exit(1)` can not be intercepted.
+
+```
+...
+handler := func() {
+  // gracefully shutdown something...
+}
+logrus.RegisterExitHandler(handler)
+...
+```
+
+#### Thread safety
+
+By default Logger is protected by mutex for concurrent writes, this mutex is invoked when calling hooks and writing logs.
+If you are sure such locking is not needed, you can call logger.SetNoLock() to disable the locking.
+
+Situation when locking is not needed includes:
+
+* You have no hooks registered, or hooks calling is already thread-safe.
+
+* Writing to logger.Out is already thread-safe, for example:
+
+  1) logger.Out is protected by locks.
+
+  2) logger.Out is a os.File handler opened with `O_APPEND` flag, and every write is smaller than 4k. (This allow multi-thread/multi-process writing)
+
+     (Refer to http://www.notthewizard.com/2014/06/17/are-files-appends-really-atomic/)

vendor/github.com/sirupsen/logrus/alt_exit.go

@@ -0,0 +1,64 @@
+package logrus
+
+// The following code was sourced and modified from the
+// https://github.com/tebeka/atexit package governed by the following license:
+//
+// Copyright (c) 2012 Miki Tebeka <miki.tebeka@gmail.com>.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do so,
+// subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+import (
+	"fmt"
+	"os"
+)
+
+var handlers = []func(){}
+
+func runHandler(handler func()) {
+	defer func() {
+		if err := recover(); err != nil {
+			fmt.Fprintln(os.Stderr, "Error: Logrus exit handler error:", err)
+		}
+	}()
+
+	handler()
+}
+
+func runHandlers() {
+	for _, handler := range handlers {
+		runHandler(handler)
+	}
+}
+
+// Exit runs all the Logrus atexit handlers and then terminates the program using os.Exit(code)
+func Exit(code int) {
+	runHandlers()
+	os.Exit(code)
+}
+
+// RegisterExitHandler adds a Logrus Exit handler, call logrus.Exit to invoke
+// all handlers. The handlers will also be invoked when any Fatal log entry is
+// made.
+//
+// This method is useful when a caller wishes to use logrus to log a fatal
+// message but also needs to gracefully shutdown. An example usecase could be
+// closing database connections, or sending a alert that the application is
+// closing.
+func RegisterExitHandler(handler func()) {
+	handlers = append(handlers, handler)
+}

vendor/github.com/sirupsen/logrus/appveyor.yml

@@ -0,0 +1,14 @@
+version: "{build}"
+platform: x64
+clone_folder: c:\gopath\src\github.com\sirupsen\logrus
+environment:  
+  GOPATH: c:\gopath
+branches:  
+  only:
+    - master
+install:  
+  - set PATH=%GOPATH%\bin;c:\go\bin;%PATH%
+  - go version
+build_script:  
+  - go get -t
+  - go test

vendor/github.com/sirupsen/logrus/doc.go

@@ -0,0 +1,26 @@
+/*
+Package logrus is a structured logger for Go, completely API compatible with the standard library logger.
+
+
+The simplest way to use Logrus is simply the package-level exported logger:
+
+  package main
+
+  import (
+    log "github.com/sirupsen/logrus"
+  )
+
+  func main() {
+    log.WithFields(log.Fields{
+      "animal": "walrus",
+      "number": 1,
+      "size":   10,
+    }).Info("A walrus appears")
+  }
+
+Output:
+  time="2015-09-07T08:48:33Z" level=info msg="A walrus appears" animal=walrus number=1 size=10
+
+For a full guide visit https://github.com/sirupsen/logrus
+*/
+package logrus

vendor/github.com/sirupsen/logrus/entry.go

@@ -0,0 +1,279 @@
+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"sync"
+	"time"
+)
+
+var bufferPool *sync.Pool
+
+func init() {
+	bufferPool = &sync.Pool{
+		New: func() interface{} {
+			return new(bytes.Buffer)
+		},
+	}
+}
+
+// Defines the key when adding errors using WithError.
+var ErrorKey = "error"
+
+// An entry is the final or intermediate Logrus logging entry. It contains all
+// the fields passed with WithField{,s}. It's finally logged when Debug, Info,
+// Warn, Error, Fatal or Panic is called on it. These objects can be reused and
+// passed around as much as you wish to avoid field duplication.
+type Entry struct {
+	Logger *Logger
+
+	// Contains all the fields set by the user.
+	Data Fields
+
+	// Time at which the log entry was created
+	Time time.Time
+
+	// Level the log entry was logged at: Debug, Info, Warn, Error, Fatal or Panic
+	// This field will be set on entry firing and the value will be equal to the one in Logger struct field.
+	Level Level
+
+	// Message passed to Debug, Info, Warn, Error, Fatal or Panic
+	Message string
+
+	// When formatter is called in entry.log(), an Buffer may be set to entry
+	Buffer *bytes.Buffer
+}
+
+func NewEntry(logger *Logger) *Entry {
+	return &Entry{
+		Logger: logger,
+		// Default is three fields, give a little extra room
+		Data: make(Fields, 5),
+	}
+}
+
+// Returns the string representation from the reader and ultimately the
+// formatter.
+func (entry *Entry) String() (string, error) {
+	serialized, err := entry.Logger.Formatter.Format(entry)
+	if err != nil {
+		return "", err
+	}
+	str := string(serialized)
+	return str, nil
+}
+
+// Add an error as single field (using the key defined in ErrorKey) to the Entry.
+func (entry *Entry) WithError(err error) *Entry {
+	return entry.WithField(ErrorKey, err)
+}
+
+// Add a single field to the Entry.
+func (entry *Entry) WithField(key string, value interface{}) *Entry {
+	return entry.WithFields(Fields{key: value})
+}
+
+// Add a map of fields to the Entry.
+func (entry *Entry) WithFields(fields Fields) *Entry {
+	data := make(Fields, len(entry.Data)+len(fields))
+	for k, v := range entry.Data {
+		data[k] = v
+	}
+	for k, v := range fields {
+		data[k] = v
+	}
+	return &Entry{Logger: entry.Logger, Data: data}
+}
+
+// This function is not declared with a pointer value because otherwise
+// race conditions will occur when using multiple goroutines
+func (entry Entry) log(level Level, msg string) {
+	var buffer *bytes.Buffer
+	entry.Time = time.Now()
+	entry.Level = level
+	entry.Message = msg
+
+	entry.Logger.mu.Lock()
+	err := entry.Logger.Hooks.Fire(level, &entry)
+	entry.Logger.mu.Unlock()
+	if err != nil {
+		entry.Logger.mu.Lock()
+		fmt.Fprintf(os.Stderr, "Failed to fire hook: %v\n", err)
+		entry.Logger.mu.Unlock()
+	}
+	buffer = bufferPool.Get().(*bytes.Buffer)
+	buffer.Reset()
+	defer bufferPool.Put(buffer)
+	entry.Buffer = buffer
+	serialized, err := entry.Logger.Formatter.Format(&entry)
+	entry.Buffer = nil
+	if err != nil {
+		entry.Logger.mu.Lock()
+		fmt.Fprintf(os.Stderr, "Failed to obtain reader, %v\n", err)
+		entry.Logger.mu.Unlock()
+	} else {
+		entry.Logger.mu.Lock()
+		_, err = entry.Logger.Out.Write(serialized)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Failed to write to log, %v\n", err)
+		}
+		entry.Logger.mu.Unlock()
+	}
+
+	// To avoid Entry#log() returning a value that only would make sense for
+	// panic() to use in Entry#Panic(), we avoid the allocation by checking
+	// directly here.
+	if level <= PanicLevel {
+		panic(&entry)
+	}
+}
+
+func (entry *Entry) Debug(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.log(DebugLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Print(args ...interface{}) {
+	entry.Info(args...)
+}
+
+func (entry *Entry) Info(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.log(InfoLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warn(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.log(WarnLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Warning(args ...interface{}) {
+	entry.Warn(args...)
+}
+
+func (entry *Entry) Error(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.log(ErrorLevel, fmt.Sprint(args...))
+	}
+}
+
+func (entry *Entry) Fatal(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.log(FatalLevel, fmt.Sprint(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panic(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.log(PanicLevel, fmt.Sprint(args...))
+	}
+	panic(fmt.Sprint(args...))
+}
+
+// Entry Printf family functions
+
+func (entry *Entry) Debugf(format string, args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Infof(format string, args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Printf(format string, args ...interface{}) {
+	entry.Infof(format, args...)
+}
+
+func (entry *Entry) Warnf(format string, args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Warningf(format string, args ...interface{}) {
+	entry.Warnf(format, args...)
+}
+
+func (entry *Entry) Errorf(format string, args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(fmt.Sprintf(format, args...))
+	}
+}
+
+func (entry *Entry) Fatalf(format string, args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(fmt.Sprintf(format, args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicf(format string, args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(fmt.Sprintf(format, args...))
+	}
+}
+
+// Entry Println family functions
+
+func (entry *Entry) Debugln(args ...interface{}) {
+	if entry.Logger.level() >= DebugLevel {
+		entry.Debug(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Infoln(args ...interface{}) {
+	if entry.Logger.level() >= InfoLevel {
+		entry.Info(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Println(args ...interface{}) {
+	entry.Infoln(args...)
+}
+
+func (entry *Entry) Warnln(args ...interface{}) {
+	if entry.Logger.level() >= WarnLevel {
+		entry.Warn(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Warningln(args ...interface{}) {
+	entry.Warnln(args...)
+}
+
+func (entry *Entry) Errorln(args ...interface{}) {
+	if entry.Logger.level() >= ErrorLevel {
+		entry.Error(entry.sprintlnn(args...))
+	}
+}
+
+func (entry *Entry) Fatalln(args ...interface{}) {
+	if entry.Logger.level() >= FatalLevel {
+		entry.Fatal(entry.sprintlnn(args...))
+	}
+	Exit(1)
+}
+
+func (entry *Entry) Panicln(args ...interface{}) {
+	if entry.Logger.level() >= PanicLevel {
+		entry.Panic(entry.sprintlnn(args...))
+	}
+}
+
+// Sprintlnn => Sprint no newline. This is to get the behavior of how
+// fmt.Sprintln where spaces are always added between operands, regardless of
+// their type. Instead of vendoring the Sprintln implementation to spare a
+// string allocation, we do the simplest thing.
+func (entry *Entry) sprintlnn(args ...interface{}) string {
+	msg := fmt.Sprintln(args...)
+	return msg[:len(msg)-1]
+}

vendor/github.com/sirupsen/logrus/exported.go

@@ -0,0 +1,193 @@
+package logrus
+
+import (
+	"io"
+)
+
+var (
+	// std is the name of the standard logger in stdlib `log`
+	std = New()
+)
+
+func StandardLogger() *Logger {
+	return std
+}
+
+// SetOutput sets the standard logger output.
+func SetOutput(out io.Writer) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Out = out
+}
+
+// SetFormatter sets the standard logger formatter.
+func SetFormatter(formatter Formatter) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Formatter = formatter
+}
+
+// SetLevel sets the standard logger level.
+func SetLevel(level Level) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.SetLevel(level)
+}
+
+// GetLevel returns the standard logger level.
+func GetLevel() Level {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	return std.level()
+}
+
+// AddHook adds a hook to the standard logger hooks.
+func AddHook(hook Hook) {
+	std.mu.Lock()
+	defer std.mu.Unlock()
+	std.Hooks.Add(hook)
+}
+
+// WithError creates an entry from the standard logger and adds an error to it, using the value defined in ErrorKey as key.
+func WithError(err error) *Entry {
+	return std.WithField(ErrorKey, err)
+}
+
+// WithField creates an entry from the standard logger and adds a field to
+// it. If you want multiple fields, use `WithFields`.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithField(key string, value interface{}) *Entry {
+	return std.WithField(key, value)
+}
+
+// WithFields creates an entry from the standard logger and adds multiple
+// fields to it. This is simply a helper for `WithField`, invoking it
+// once for each field.
+//
+// Note that it doesn't log until you call Debug, Print, Info, Warn, Fatal
+// or Panic on the Entry it returns.
+func WithFields(fields Fields) *Entry {
+	return std.WithFields(fields)
+}
+
+// Debug logs a message at level Debug on the standard logger.
+func Debug(args ...interface{}) {
+	std.Debug(args...)
+}
+
+// Print logs a message at level Info on the standard logger.
+func Print(args ...interface{}) {
+	std.Print(args...)
+}
+
+// Info logs a message at level Info on the standard logger.
+func Info(args ...interface{}) {
+	std.Info(args...)
+}
+
+// Warn logs a message at level Warn on the standard logger.
+func Warn(args ...interface{}) {
+	std.Warn(args...)
+}
+
+// Warning logs a message at level Warn on the standard logger.
+func Warning(args ...interface{}) {
+	std.Warning(args...)
+}
+
+// Error logs a message at level Error on the standard logger.
+func Error(args ...interface{}) {
+	std.Error(args...)
+}
+
+// Panic logs a message at level Panic on the standard logger.
+func Panic(args ...interface{}) {
+	std.Panic(args...)
+}
+
+// Fatal logs a message at level Fatal on the standard logger.
+func Fatal(args ...interface{}) {
+	std.Fatal(args...)
+}
+
+// Debugf logs a message at level Debug on the standard logger.
+func Debugf(format string, args ...interface{}) {
+	std.Debugf(format, args...)
+}
+
+// Printf logs a message at level Info on the standard logger.
+func Printf(format string, args ...interface{}) {
+	std.Printf(format, args...)
+}
+
+// Infof logs a message at level Info on the standard logger.
+func Infof(format string, args ...interface{}) {
+	std.Infof(format, args...)
+}
+
+// Warnf logs a message at level Warn on the standard logger.
+func Warnf(format string, args ...interface{}) {
+	std.Warnf(format, args...)
+}
+
+// Warningf logs a message at level Warn on the standard logger.
+func Warningf(format string, args ...interface{}) {
+	std.Warningf(format, args...)
+}
+
+// Errorf logs a message at level Error on the standard logger.
+func Errorf(format string, args ...interface{}) {
+	std.Errorf(format, args...)
+}
+
+// Panicf logs a message at level Panic on the standard logger.
+func Panicf(format string, args ...interface{}) {
+	std.Panicf(format, args...)
+}
+
+// Fatalf logs a message at level Fatal on the standard logger.
+func Fatalf(format string, args ...interface{}) {
+	std.Fatalf(format, args...)
+}
+
+// Debugln logs a message at level Debug on the standard logger.
+func Debugln(args ...interface{}) {
+	std.Debugln(args...)
+}
+
+// Println logs a message at level Info on the standard logger.
+func Println(args ...interface{}) {
+	std.Println(args...)
+}
+
+// Infoln logs a message at level Info on the standard logger.
+func Infoln(args ...interface{}) {
+	std.Infoln(args...)
+}
+
+// Warnln logs a message at level Warn on the standard logger.
+func Warnln(args ...interface{}) {
+	std.Warnln(args...)
+}
+
+// Warningln logs a message at level Warn on the standard logger.
+func Warningln(args ...interface{}) {
+	std.Warningln(args...)
+}
+
+// Errorln logs a message at level Error on the standard logger.
+func Errorln(args ...interface{}) {
+	std.Errorln(args...)
+}
+
+// Panicln logs a message at level Panic on the standard logger.
+func Panicln(args ...interface{}) {
+	std.Panicln(args...)
+}
+
+// Fatalln logs a message at level Fatal on the standard logger.
+func Fatalln(args ...interface{}) {
+	std.Fatalln(args...)
+}

vendor/github.com/sirupsen/logrus/formatter.go

@@ -0,0 +1,45 @@
+package logrus
+
+import "time"
+
+const defaultTimestampFormat = time.RFC3339
+
+// The Formatter interface is used to implement a custom Formatter. It takes an
+// `Entry`. It exposes all the fields, including the default ones:
+//
+// * `entry.Data["msg"]`. The message passed from Info, Warn, Error ..
+// * `entry.Data["time"]`. The timestamp.
+// * `entry.Data["level"]. The level the entry was logged at.
+//
+// Any additional fields added with `WithField` or `WithFields` are also in
+// `entry.Data`. Format is expected to return an array of bytes which are then
+// logged to `logger.Out`.
+type Formatter interface {
+	Format(*Entry) ([]byte, error)
+}
+
+// This is to not silently overwrite `time`, `msg` and `level` fields when
+// dumping it. If this code wasn't there doing:
+//
+//  logrus.WithField("level", 1).Info("hello")
+//
+// Would just silently drop the user provided level. Instead with this code
+// it'll logged as:
+//
+//  {"level": "info", "fields.level": 1, "msg": "hello", "time": "..."}
+//
+// It's not exported because it's still using Data in an opinionated way. It's to
+// avoid code duplication between the two default formatters.
+func prefixFieldClashes(data Fields) {
+	if t, ok := data["time"]; ok {
+		data["fields.time"] = t
+	}
+
+	if m, ok := data["msg"]; ok {
+		data["fields.msg"] = m
+	}
+
+	if l, ok := data["level"]; ok {
+		data["fields.level"] = l
+	}
+}

vendor/github.com/sirupsen/logrus/hooks.go

@@ -0,0 +1,34 @@
+package logrus
+
+// A hook to be fired when logging on the logging levels returned from
+// `Levels()` on your implementation of the interface. Note that this is not
+// fired in a goroutine or a channel with workers, you should handle such
+// functionality yourself if your call is non-blocking and you don't wish for
+// the logging calls for levels returned from `Levels()` to block.
+type Hook interface {
+	Levels() []Level
+	Fire(*Entry) error
+}
+
+// Internal type for storing the hooks on a logger instance.
+type LevelHooks map[Level][]Hook
+
+// Add a hook to an instance of logger. This is called with
+// `log.Hooks.Add(new(MyHook))` where `MyHook` implements the `Hook` interface.
+func (hooks LevelHooks) Add(hook Hook) {
+	for _, level := range hook.Levels() {
+		hooks[level] = append(hooks[level], hook)
+	}
+}
+
+// Fire all the hooks for the passed level. Used by `entry.log` to fire
+// appropriate hooks for a log entry.
+func (hooks LevelHooks) Fire(level Level, entry *Entry) error {
+	for _, hook := range hooks[level] {
+		if err := hook.Fire(entry); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

vendor/github.com/sirupsen/logrus/json_formatter.go

@@ -0,0 +1,79 @@
+package logrus
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+type fieldKey string
+
+// FieldMap allows customization of the key names for default fields.
+type FieldMap map[fieldKey]string
+
+// Default key names for the default fields
+const (
+	FieldKeyMsg   = "msg"
+	FieldKeyLevel = "level"
+	FieldKeyTime  = "time"
+)
+
+func (f FieldMap) resolve(key fieldKey) string {
+	if k, ok := f[key]; ok {
+		return k
+	}
+
+	return string(key)
+}
+
+// JSONFormatter formats logs into parsable json
+type JSONFormatter struct {
+	// TimestampFormat sets the format used for marshaling timestamps.
+	TimestampFormat string
+
+	// DisableTimestamp allows disabling automatic timestamps in output
+	DisableTimestamp bool
+
+	// FieldMap allows users to customize the names of keys for default fields.
+	// As an example:
+	// formatter := &JSONFormatter{
+	//   	FieldMap: FieldMap{
+	// 		 FieldKeyTime: "@timestamp",
+	// 		 FieldKeyLevel: "@level",
+	// 		 FieldKeyMsg: "@message",
+	//    },
+	// }
+	FieldMap FieldMap
+}
+
+// Format renders a single log entry
+func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
+	data := make(Fields, len(entry.Data)+3)
+	for k, v := range entry.Data {
+		switch v := v.(type) {
+		case error:
+			// Otherwise errors are ignored by `encoding/json`
+			// https://github.com/sirupsen/logrus/issues/137
+			data[k] = v.Error()
+		default:
+			data[k] = v
+		}
+	}
+	prefixFieldClashes(data)
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+
+	if !f.DisableTimestamp {
+		data[f.FieldMap.resolve(FieldKeyTime)] = entry.Time.Format(timestampFormat)
+	}
+	data[f.FieldMap.resolve(FieldKeyMsg)] = entry.Message
+	data[f.FieldMap.resolve(FieldKeyLevel)] = entry.Level.String()
+
+	serialized, err := json.Marshal(data)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+	}
+	return append(serialized, '\n'), nil
+}

vendor/github.com/sirupsen/logrus/logger.go

@@ -0,0 +1,323 @@
+package logrus
+
+import (
+	"io"
+	"os"
+	"sync"
+	"sync/atomic"
+)
+
+type Logger struct {
+	// The logs are `io.Copy`'d to this in a mutex. It's common to set this to a
+	// file, or leave it default which is `os.Stderr`. You can also set this to
+	// something more adventorous, such as logging to Kafka.
+	Out io.Writer
+	// Hooks for the logger instance. These allow firing events based on logging
+	// levels and log entries. For example, to send errors to an error tracking
+	// service, log to StatsD or dump the core on fatal errors.
+	Hooks LevelHooks
+	// All log entries pass through the formatter before logged to Out. The
+	// included formatters are `TextFormatter` and `JSONFormatter` for which
+	// TextFormatter is the default. In development (when a TTY is attached) it
+	// logs with colors, but to a file it wouldn't. You can easily implement your
+	// own that implements the `Formatter` interface, see the `README` or included
+	// formatters for examples.
+	Formatter Formatter
+	// The logging level the logger should log at. This is typically (and defaults
+	// to) `logrus.Info`, which allows Info(), Warn(), Error() and Fatal() to be
+	// logged.
+	Level Level
+	// Used to sync writing to the log. Locking is enabled by Default
+	mu MutexWrap
+	// Reusable empty entry
+	entryPool sync.Pool
+}
+
+type MutexWrap struct {
+	lock     sync.Mutex
+	disabled bool
+}
+
+func (mw *MutexWrap) Lock() {
+	if !mw.disabled {
+		mw.lock.Lock()
+	}
+}
+
+func (mw *MutexWrap) Unlock() {
+	if !mw.disabled {
+		mw.lock.Unlock()
+	}
+}
+
+func (mw *MutexWrap) Disable() {
+	mw.disabled = true
+}
+
+// Creates a new logger. Configuration should be set by changing `Formatter`,
+// `Out` and `Hooks` directly on the default logger instance. You can also just
+// instantiate your own:
+//
+//    var log = &Logger{
+//      Out: os.Stderr,
+//      Formatter: new(JSONFormatter),
+//      Hooks: make(LevelHooks),
+//      Level: logrus.DebugLevel,
+//    }
+//
+// It's recommended to make this a global instance called `log`.
+func New() *Logger {
+	return &Logger{
+		Out:       os.Stderr,
+		Formatter: new(TextFormatter),
+		Hooks:     make(LevelHooks),
+		Level:     InfoLevel,
+	}
+}
+
+func (logger *Logger) newEntry() *Entry {
+	entry, ok := logger.entryPool.Get().(*Entry)
+	if ok {
+		return entry
+	}
+	return NewEntry(logger)
+}
+
+func (logger *Logger) releaseEntry(entry *Entry) {
+	logger.entryPool.Put(entry)
+}
+
+// Adds a field to the log entry, note that it doesn't log until you call
+// Debug, Print, Info, Warn, Fatal or Panic. It only creates a log entry.
+// If you want multiple fields, use `WithFields`.
+func (logger *Logger) WithField(key string, value interface{}) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithField(key, value)
+}
+
+// Adds a struct of fields to the log entry. All it does is call `WithField` for
+// each `Field`.
+func (logger *Logger) WithFields(fields Fields) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithFields(fields)
+}
+
+// Add an error as single field to the log entry.  All it does is call
+// `WithError` for the given `error`.
+func (logger *Logger) WithError(err error) *Entry {
+	entry := logger.newEntry()
+	defer logger.releaseEntry(entry)
+	return entry.WithError(err)
+}
+
+func (logger *Logger) Debugf(format string, args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infof(format string, args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infof(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Printf(format string, args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Printf(format, args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningf(format string, args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorf(format string, args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalf(format string, args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalf(format, args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicf(format string, args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicf(format, args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debug(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debug(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Info(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Info(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Print(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Info(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warn(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warning(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warn(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Error(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Error(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatal(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatal(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panic(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panic(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Debugln(args ...interface{}) {
+	if logger.level() >= DebugLevel {
+		entry := logger.newEntry()
+		entry.Debugln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Infoln(args ...interface{}) {
+	if logger.level() >= InfoLevel {
+		entry := logger.newEntry()
+		entry.Infoln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Println(args ...interface{}) {
+	entry := logger.newEntry()
+	entry.Println(args...)
+	logger.releaseEntry(entry)
+}
+
+func (logger *Logger) Warnln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Warningln(args ...interface{}) {
+	if logger.level() >= WarnLevel {
+		entry := logger.newEntry()
+		entry.Warnln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Errorln(args ...interface{}) {
+	if logger.level() >= ErrorLevel {
+		entry := logger.newEntry()
+		entry.Errorln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+func (logger *Logger) Fatalln(args ...interface{}) {
+	if logger.level() >= FatalLevel {
+		entry := logger.newEntry()
+		entry.Fatalln(args...)
+		logger.releaseEntry(entry)
+	}
+	Exit(1)
+}
+
+func (logger *Logger) Panicln(args ...interface{}) {
+	if logger.level() >= PanicLevel {
+		entry := logger.newEntry()
+		entry.Panicln(args...)
+		logger.releaseEntry(entry)
+	}
+}
+
+//When file is opened with appending mode, it's safe to
+//write concurrently to a file (within 4k message on Linux).
+//In these cases user can choose to disable the lock.
+func (logger *Logger) SetNoLock() {
+	logger.mu.Disable()
+}
+
+func (logger *Logger) level() Level {
+	return Level(atomic.LoadUint32((*uint32)(&logger.Level)))
+}
+
+func (logger *Logger) SetLevel(level Level) {
+	atomic.StoreUint32((*uint32)(&logger.Level), uint32(level))
+}
+
+func (logger *Logger) AddHook(hook Hook) {
+	logger.mu.Lock()
+	defer logger.mu.Unlock()
+	logger.Hooks.Add(hook)
+}

vendor/github.com/sirupsen/logrus/logrus.go

@@ -0,0 +1,143 @@
+package logrus
+
+import (
+	"fmt"
+	"log"
+	"strings"
+)
+
+// Fields type, used to pass to `WithFields`.
+type Fields map[string]interface{}
+
+// Level type
+type Level uint32
+
+// Convert the Level to a string. E.g. PanicLevel becomes "panic".
+func (level Level) String() string {
+	switch level {
+	case DebugLevel:
+		return "debug"
+	case InfoLevel:
+		return "info"
+	case WarnLevel:
+		return "warning"
+	case ErrorLevel:
+		return "error"
+	case FatalLevel:
+		return "fatal"
+	case PanicLevel:
+		return "panic"
+	}
+
+	return "unknown"
+}
+
+// ParseLevel takes a string level and returns the Logrus log level constant.
+func ParseLevel(lvl string) (Level, error) {
+	switch strings.ToLower(lvl) {
+	case "panic":
+		return PanicLevel, nil
+	case "fatal":
+		return FatalLevel, nil
+	case "error":
+		return ErrorLevel, nil
+	case "warn", "warning":
+		return WarnLevel, nil
+	case "info":
+		return InfoLevel, nil
+	case "debug":
+		return DebugLevel, nil
+	}
+
+	var l Level
+	return l, fmt.Errorf("not a valid logrus Level: %q", lvl)
+}
+
+// A constant exposing all logging levels
+var AllLevels = []Level{
+	PanicLevel,
+	FatalLevel,
+	ErrorLevel,
+	WarnLevel,
+	InfoLevel,
+	DebugLevel,
+}
+
+// These are the different logging levels. You can set the logging level to log
+// on your instance of logger, obtained with `logrus.New()`.
+const (
+	// PanicLevel level, highest level of severity. Logs and then calls panic with the
+	// message passed to Debug, Info, ...
+	PanicLevel Level = iota
+	// FatalLevel level. Logs and then calls `os.Exit(1)`. It will exit even if the
+	// logging level is set to Panic.
+	FatalLevel
+	// ErrorLevel level. Logs. Used for errors that should definitely be noted.
+	// Commonly used for hooks to send errors to an error tracking service.
+	ErrorLevel
+	// WarnLevel level. Non-critical entries that deserve eyes.
+	WarnLevel
+	// InfoLevel level. General operational entries about what's going on inside the
+	// application.
+	InfoLevel
+	// DebugLevel level. Usually only enabled when debugging. Very verbose logging.
+	DebugLevel
+)
+
+// Won't compile if StdLogger can't be realized by a log.Logger
+var (
+	_ StdLogger = &log.Logger{}
+	_ StdLogger = &Entry{}
+	_ StdLogger = &Logger{}
+)
+
+// StdLogger is what your logrus-enabled library should take, that way
+// it'll accept a stdlib logger and a logrus logger. There's no standard
+// interface, this is the closest we get, unfortunately.
+type StdLogger interface {
+	Print(...interface{})
+	Printf(string, ...interface{})
+	Println(...interface{})
+
+	Fatal(...interface{})
+	Fatalf(string, ...interface{})
+	Fatalln(...interface{})
+
+	Panic(...interface{})
+	Panicf(string, ...interface{})
+	Panicln(...interface{})
+}
+
+// The FieldLogger interface generalizes the Entry and Logger types
+type FieldLogger interface {
+	WithField(key string, value interface{}) *Entry
+	WithFields(fields Fields) *Entry
+	WithError(err error) *Entry
+
+	Debugf(format string, args ...interface{})
+	Infof(format string, args ...interface{})
+	Printf(format string, args ...interface{})
+	Warnf(format string, args ...interface{})
+	Warningf(format string, args ...interface{})
+	Errorf(format string, args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Panicf(format string, args ...interface{})
+
+	Debug(args ...interface{})
+	Info(args ...interface{})
+	Print(args ...interface{})
+	Warn(args ...interface{})
+	Warning(args ...interface{})
+	Error(args ...interface{})
+	Fatal(args ...interface{})
+	Panic(args ...interface{})
+
+	Debugln(args ...interface{})
+	Infoln(args ...interface{})
+	Println(args ...interface{})
+	Warnln(args ...interface{})
+	Warningln(args ...interface{})
+	Errorln(args ...interface{})
+	Fatalln(args ...interface{})
+	Panicln(args ...interface{})
+}

vendor/github.com/sirupsen/logrus/terminal_bsd.go

@@ -0,0 +1,10 @@
+// +build darwin freebsd openbsd netbsd dragonfly
+// +build !appengine
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+
+type Termios unix.Termios

vendor/github.com/sirupsen/logrus/terminal_linux.go

@@ -0,0 +1,14 @@
+// Based on ssh/terminal:
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !appengine
+
+package logrus
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+
+type Termios unix.Termios

vendor/github.com/sirupsen/logrus/text_formatter.go

@@ -0,0 +1,191 @@
+package logrus
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+const (
+	nocolor = 0
+	red     = 31
+	green   = 32
+	yellow  = 33
+	blue    = 36
+	gray    = 37
+)
+
+var (
+	baseTimestamp time.Time
+)
+
+func init() {
+	baseTimestamp = time.Now()
+}
+
+// TextFormatter formats logs into text
+type TextFormatter struct {
+	// Set to true to bypass checking for a TTY before outputting colors.
+	ForceColors bool
+
+	// Force disabling colors.
+	DisableColors bool
+
+	// Disable timestamp logging. useful when output is redirected to logging
+	// system that already adds timestamps.
+	DisableTimestamp bool
+
+	// Enable logging the full timestamp when a TTY is attached instead of just
+	// the time passed since beginning of execution.
+	FullTimestamp bool
+
+	// TimestampFormat to use for display when a full timestamp is printed
+	TimestampFormat string
+
+	// The fields are sorted by default for a consistent output. For applications
+	// that log extremely frequently and don't use the JSON formatter this may not
+	// be desired.
+	DisableSorting bool
+
+	// QuoteEmptyFields will wrap empty fields in quotes if true
+	QuoteEmptyFields bool
+
+	// Whether the logger's out is to a terminal
+	isTerminal bool
+
+	sync.Once
+}
+
+func (f *TextFormatter) init(entry *Entry) {
+	if entry.Logger != nil {
+		f.isTerminal = f.checkIfTerminal(entry.Logger.Out)
+	}
+}
+
+func (f *TextFormatter) checkIfTerminal(w io.Writer) bool {
+	switch v := w.(type) {
+	case *os.File:
+		return terminal.IsTerminal(int(v.Fd()))
+	default:
+		return false
+	}
+}
+
+// Format renders a single log entry
+func (f *TextFormatter) Format(entry *Entry) ([]byte, error) {
+	var b *bytes.Buffer
+	keys := make([]string, 0, len(entry.Data))
+	for k := range entry.Data {
+		keys = append(keys, k)
+	}
+
+	if !f.DisableSorting {
+		sort.Strings(keys)
+	}
+	if entry.Buffer != nil {
+		b = entry.Buffer
+	} else {
+		b = &bytes.Buffer{}
+	}
+
+	prefixFieldClashes(entry.Data)
+
+	f.Do(func() { f.init(entry) })
+
+	isColored := (f.ForceColors || f.isTerminal) && !f.DisableColors
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = defaultTimestampFormat
+	}
+	if isColored {
+		f.printColored(b, entry, keys, timestampFormat)
+	} else {
+		if !f.DisableTimestamp {
+			f.appendKeyValue(b, "time", entry.Time.Format(timestampFormat))
+		}
+		f.appendKeyValue(b, "level", entry.Level.String())
+		if entry.Message != "" {
+			f.appendKeyValue(b, "msg", entry.Message)
+		}
+		for _, key := range keys {
+			f.appendKeyValue(b, key, entry.Data[key])
+		}
+	}
+
+	b.WriteByte('\n')
+	return b.Bytes(), nil
+}
+
+func (f *TextFormatter) printColored(b *bytes.Buffer, entry *Entry, keys []string, timestampFormat string) {
+	var levelColor int
+	switch entry.Level {
+	case DebugLevel:
+		levelColor = gray
+	case WarnLevel:
+		levelColor = yellow
+	case ErrorLevel, FatalLevel, PanicLevel:
+		levelColor = red
+	default:
+		levelColor = blue
+	}
+
+	levelText := strings.ToUpper(entry.Level.String())[0:4]
+
+	if f.DisableTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m %-44s ", levelColor, levelText, entry.Message)
+	} else if !f.FullTimestamp {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%04d] %-44s ", levelColor, levelText, int(entry.Time.Sub(baseTimestamp)/time.Second), entry.Message)
+	} else {
+		fmt.Fprintf(b, "\x1b[%dm%s\x1b[0m[%s] %-44s ", levelColor, levelText, entry.Time.Format(timestampFormat), entry.Message)
+	}
+	for _, k := range keys {
+		v := entry.Data[k]
+		fmt.Fprintf(b, " \x1b[%dm%s\x1b[0m=", levelColor, k)
+		f.appendValue(b, v)
+	}
+}
+
+func (f *TextFormatter) needsQuoting(text string) bool {
+	if f.QuoteEmptyFields && len(text) == 0 {
+		return true
+	}
+	for _, ch := range text {
+		if !((ch >= 'a' && ch <= 'z') ||
+			(ch >= 'A' && ch <= 'Z') ||
+			(ch >= '0' && ch <= '9') ||
+			ch == '-' || ch == '.' || ch == '_' || ch == '/' || ch == '@' || ch == '^' || ch == '+') {
+			return true
+		}
+	}
+	return false
+}
+
+func (f *TextFormatter) appendKeyValue(b *bytes.Buffer, key string, value interface{}) {
+	if b.Len() > 0 {
+		b.WriteByte(' ')
+	}
+	b.WriteString(key)
+	b.WriteByte('=')
+	f.appendValue(b, value)
+}
+
+func (f *TextFormatter) appendValue(b *bytes.Buffer, value interface{}) {
+	stringVal, ok := value.(string)
+	if !ok {
+		stringVal = fmt.Sprint(value)
+	}
+
+	if !f.needsQuoting(stringVal) {
+		b.WriteString(stringVal)
+	} else {
+		b.WriteString(fmt.Sprintf("%q", stringVal))
+	}
+}

vendor/github.com/sirupsen/logrus/writer.go

@@ -0,0 +1,62 @@
+package logrus
+
+import (
+	"bufio"
+	"io"
+	"runtime"
+)
+
+func (logger *Logger) Writer() *io.PipeWriter {
+	return logger.WriterLevel(InfoLevel)
+}
+
+func (logger *Logger) WriterLevel(level Level) *io.PipeWriter {
+	return NewEntry(logger).WriterLevel(level)
+}
+
+func (entry *Entry) Writer() *io.PipeWriter {
+	return entry.WriterLevel(InfoLevel)
+}
+
+func (entry *Entry) WriterLevel(level Level) *io.PipeWriter {
+	reader, writer := io.Pipe()
+
+	var printFunc func(args ...interface{})
+
+	switch level {
+	case DebugLevel:
+		printFunc = entry.Debug
+	case InfoLevel:
+		printFunc = entry.Info
+	case WarnLevel:
+		printFunc = entry.Warn
+	case ErrorLevel:
+		printFunc = entry.Error
+	case FatalLevel:
+		printFunc = entry.Fatal
+	case PanicLevel:
+		printFunc = entry.Panic
+	default:
+		printFunc = entry.Print
+	}
+
+	go entry.writerScanner(reader, printFunc)
+	runtime.SetFinalizer(writer, writerFinalizer)
+
+	return writer
+}
+
+func (entry *Entry) writerScanner(reader *io.PipeReader, printFunc func(args ...interface{})) {
+	scanner := bufio.NewScanner(reader)
+	for scanner.Scan() {
+		printFunc(scanner.Text())
+	}
+	if err := scanner.Err(); err != nil {
+		entry.Errorf("Error while reading from Writer: %s", err)
+	}
+	reader.Close()
+}
+
+func writerFinalizer(writer *io.PipeWriter) {
+	writer.Close()
+}

vendor/golang.org/x/crypto/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/crypto/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/crypto/ssh/terminal/terminal.go

@@ -0,0 +1,951 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package terminal
+
+import (
+	"bytes"
+	"io"
+	"sync"
+	"unicode/utf8"
+)
+
+// EscapeCodes contains escape sequences that can be written to the terminal in
+// order to achieve different styles of text.
+type EscapeCodes struct {
+	// Foreground colors
+	Black, Red, Green, Yellow, Blue, Magenta, Cyan, White []byte
+
+	// Reset all attributes
+	Reset []byte
+}
+
+var vt100EscapeCodes = EscapeCodes{
+	Black:   []byte{keyEscape, '[', '3', '0', 'm'},
+	Red:     []byte{keyEscape, '[', '3', '1', 'm'},
+	Green:   []byte{keyEscape, '[', '3', '2', 'm'},
+	Yellow:  []byte{keyEscape, '[', '3', '3', 'm'},
+	Blue:    []byte{keyEscape, '[', '3', '4', 'm'},
+	Magenta: []byte{keyEscape, '[', '3', '5', 'm'},
+	Cyan:    []byte{keyEscape, '[', '3', '6', 'm'},
+	White:   []byte{keyEscape, '[', '3', '7', 'm'},
+
+	Reset: []byte{keyEscape, '[', '0', 'm'},
+}
+
+// Terminal contains the state for running a VT100 terminal that is capable of
+// reading lines of input.
+type Terminal struct {
+	// AutoCompleteCallback, if non-null, is called for each keypress with
+	// the full input line and the current position of the cursor (in
+	// bytes, as an index into |line|). If it returns ok=false, the key
+	// press is processed normally. Otherwise it returns a replacement line
+	// and the new cursor position.
+	AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool)
+
+	// Escape contains a pointer to the escape codes for this terminal.
+	// It's always a valid pointer, although the escape codes themselves
+	// may be empty if the terminal doesn't support them.
+	Escape *EscapeCodes
+
+	// lock protects the terminal and the state in this object from
+	// concurrent processing of a key press and a Write() call.
+	lock sync.Mutex
+
+	c      io.ReadWriter
+	prompt []rune
+
+	// line is the current line being entered.
+	line []rune
+	// pos is the logical position of the cursor in line
+	pos int
+	// echo is true if local echo is enabled
+	echo bool
+	// pasteActive is true iff there is a bracketed paste operation in
+	// progress.
+	pasteActive bool
+
+	// cursorX contains the current X value of the cursor where the left
+	// edge is 0. cursorY contains the row number where the first row of
+	// the current line is 0.
+	cursorX, cursorY int
+	// maxLine is the greatest value of cursorY so far.
+	maxLine int
+
+	termWidth, termHeight int
+
+	// outBuf contains the terminal data to be sent.
+	outBuf []byte
+	// remainder contains the remainder of any partial key sequences after
+	// a read. It aliases into inBuf.
+	remainder []byte
+	inBuf     [256]byte
+
+	// history contains previously entered commands so that they can be
+	// accessed with the up and down keys.
+	history stRingBuffer
+	// historyIndex stores the currently accessed history entry, where zero
+	// means the immediately previous entry.
+	historyIndex int
+	// When navigating up and down the history it's possible to return to
+	// the incomplete, initial line. That value is stored in
+	// historyPending.
+	historyPending string
+}
+
+// NewTerminal runs a VT100 terminal on the given ReadWriter. If the ReadWriter is
+// a local terminal, that terminal must first have been put into raw mode.
+// prompt is a string that is written at the start of each input line (i.e.
+// "> ").
+func NewTerminal(c io.ReadWriter, prompt string) *Terminal {
+	return &Terminal{
+		Escape:       &vt100EscapeCodes,
+		c:            c,
+		prompt:       []rune(prompt),
+		termWidth:    80,
+		termHeight:   24,
+		echo:         true,
+		historyIndex: -1,
+	}
+}
+
+const (
+	keyCtrlD     = 4
+	keyCtrlU     = 21
+	keyEnter     = '\r'
+	keyEscape    = 27
+	keyBackspace = 127
+	keyUnknown   = 0xd800 /* UTF-16 surrogate area */ + iota
+	keyUp
+	keyDown
+	keyLeft
+	keyRight
+	keyAltLeft
+	keyAltRight
+	keyHome
+	keyEnd
+	keyDeleteWord
+	keyDeleteLine
+	keyClearScreen
+	keyPasteStart
+	keyPasteEnd
+)
+
+var (
+	crlf       = []byte{'\r', '\n'}
+	pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
+	pasteEnd   = []byte{keyEscape, '[', '2', '0', '1', '~'}
+)
+
+// bytesToKey tries to parse a key sequence from b. If successful, it returns
+// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
+func bytesToKey(b []byte, pasteActive bool) (rune, []byte) {
+	if len(b) == 0 {
+		return utf8.RuneError, nil
+	}
+
+	if !pasteActive {
+		switch b[0] {
+		case 1: // ^A
+			return keyHome, b[1:]
+		case 5: // ^E
+			return keyEnd, b[1:]
+		case 8: // ^H
+			return keyBackspace, b[1:]
+		case 11: // ^K
+			return keyDeleteLine, b[1:]
+		case 12: // ^L
+			return keyClearScreen, b[1:]
+		case 23: // ^W
+			return keyDeleteWord, b[1:]
+		}
+	}
+
+	if b[0] != keyEscape {
+		if !utf8.FullRune(b) {
+			return utf8.RuneError, b
+		}
+		r, l := utf8.DecodeRune(b)
+		return r, b[l:]
+	}
+
+	if !pasteActive && len(b) >= 3 && b[0] == keyEscape && b[1] == '[' {
+		switch b[2] {
+		case 'A':
+			return keyUp, b[3:]
+		case 'B':
+			return keyDown, b[3:]
+		case 'C':
+			return keyRight, b[3:]
+		case 'D':
+			return keyLeft, b[3:]
+		case 'H':
+			return keyHome, b[3:]
+		case 'F':
+			return keyEnd, b[3:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && b[0] == keyEscape && b[1] == '[' && b[2] == '1' && b[3] == ';' && b[4] == '3' {
+		switch b[5] {
+		case 'C':
+			return keyAltRight, b[6:]
+		case 'D':
+			return keyAltLeft, b[6:]
+		}
+	}
+
+	if !pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteStart) {
+		return keyPasteStart, b[6:]
+	}
+
+	if pasteActive && len(b) >= 6 && bytes.Equal(b[:6], pasteEnd) {
+		return keyPasteEnd, b[6:]
+	}
+
+	// If we get here then we have a key that we don't recognise, or a
+	// partial sequence. It's not clear how one should find the end of a
+	// sequence without knowing them all, but it seems that [a-zA-Z~] only
+	// appears at the end of a sequence.
+	for i, c := range b[0:] {
+		if c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c == '~' {
+			return keyUnknown, b[i+1:]
+		}
+	}
+
+	return utf8.RuneError, b
+}
+
+// queue appends data to the end of t.outBuf
+func (t *Terminal) queue(data []rune) {
+	t.outBuf = append(t.outBuf, []byte(string(data))...)
+}
+
+var eraseUnderCursor = []rune{' ', keyEscape, '[', 'D'}
+var space = []rune{' '}
+
+func isPrintable(key rune) bool {
+	isInSurrogateArea := key >= 0xd800 && key <= 0xdbff
+	return key >= 32 && !isInSurrogateArea
+}
+
+// moveCursorToPos appends data to t.outBuf which will move the cursor to the
+// given, logical position in the text.
+func (t *Terminal) moveCursorToPos(pos int) {
+	if !t.echo {
+		return
+	}
+
+	x := visualLength(t.prompt) + pos
+	y := x / t.termWidth
+	x = x % t.termWidth
+
+	up := 0
+	if y < t.cursorY {
+		up = t.cursorY - y
+	}
+
+	down := 0
+	if y > t.cursorY {
+		down = y - t.cursorY
+	}
+
+	left := 0
+	if x < t.cursorX {
+		left = t.cursorX - x
+	}
+
+	right := 0
+	if x > t.cursorX {
+		right = x - t.cursorX
+	}
+
+	t.cursorX = x
+	t.cursorY = y
+	t.move(up, down, left, right)
+}
+
+func (t *Terminal) move(up, down, left, right int) {
+	movement := make([]rune, 3*(up+down+left+right))
+	m := movement
+	for i := 0; i < up; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'A'
+		m = m[3:]
+	}
+	for i := 0; i < down; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'B'
+		m = m[3:]
+	}
+	for i := 0; i < left; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'D'
+		m = m[3:]
+	}
+	for i := 0; i < right; i++ {
+		m[0] = keyEscape
+		m[1] = '['
+		m[2] = 'C'
+		m = m[3:]
+	}
+
+	t.queue(movement)
+}
+
+func (t *Terminal) clearLineToRight() {
+	op := []rune{keyEscape, '[', 'K'}
+	t.queue(op)
+}
+
+const maxLineLength = 4096
+
+func (t *Terminal) setLine(newLine []rune, newPos int) {
+	if t.echo {
+		t.moveCursorToPos(0)
+		t.writeLine(newLine)
+		for i := len(newLine); i < len(t.line); i++ {
+			t.writeLine(space)
+		}
+		t.moveCursorToPos(newPos)
+	}
+	t.line = newLine
+	t.pos = newPos
+}
+
+func (t *Terminal) advanceCursor(places int) {
+	t.cursorX += places
+	t.cursorY += t.cursorX / t.termWidth
+	if t.cursorY > t.maxLine {
+		t.maxLine = t.cursorY
+	}
+	t.cursorX = t.cursorX % t.termWidth
+
+	if places > 0 && t.cursorX == 0 {
+		// Normally terminals will advance the current position
+		// when writing a character. But that doesn't happen
+		// for the last character in a line. However, when
+		// writing a character (except a new line) that causes
+		// a line wrap, the position will be advanced two
+		// places.
+		//
+		// So, if we are stopping at the end of a line, we
+		// need to write a newline so that our cursor can be
+		// advanced to the next line.
+		t.outBuf = append(t.outBuf, '\r', '\n')
+	}
+}
+
+func (t *Terminal) eraseNPreviousChars(n int) {
+	if n == 0 {
+		return
+	}
+
+	if t.pos < n {
+		n = t.pos
+	}
+	t.pos -= n
+	t.moveCursorToPos(t.pos)
+
+	copy(t.line[t.pos:], t.line[n+t.pos:])
+	t.line = t.line[:len(t.line)-n]
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+		for i := 0; i < n; i++ {
+			t.queue(space)
+		}
+		t.advanceCursor(n)
+		t.moveCursorToPos(t.pos)
+	}
+}
+
+// countToLeftWord returns then number of characters from the cursor to the
+// start of the previous word.
+func (t *Terminal) countToLeftWord() int {
+	if t.pos == 0 {
+		return 0
+	}
+
+	pos := t.pos - 1
+	for pos > 0 {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos--
+	}
+	for pos > 0 {
+		if t.line[pos] == ' ' {
+			pos++
+			break
+		}
+		pos--
+	}
+
+	return t.pos - pos
+}
+
+// countToRightWord returns then number of characters from the cursor to the
+// start of the next word.
+func (t *Terminal) countToRightWord() int {
+	pos := t.pos
+	for pos < len(t.line) {
+		if t.line[pos] == ' ' {
+			break
+		}
+		pos++
+	}
+	for pos < len(t.line) {
+		if t.line[pos] != ' ' {
+			break
+		}
+		pos++
+	}
+	return pos - t.pos
+}
+
+// visualLength returns the number of visible glyphs in s.
+func visualLength(runes []rune) int {
+	inEscapeSeq := false
+	length := 0
+
+	for _, r := range runes {
+		switch {
+		case inEscapeSeq:
+			if (r >= 'a' && r <= 'z') || (r >= 'A' && r <= 'Z') {
+				inEscapeSeq = false
+			}
+		case r == '\x1b':
+			inEscapeSeq = true
+		default:
+			length++
+		}
+	}
+
+	return length
+}
+
+// handleKey processes the given key and, optionally, returns a line of text
+// that the user has entered.
+func (t *Terminal) handleKey(key rune) (line string, ok bool) {
+	if t.pasteActive && key != keyEnter {
+		t.addKeyToLine(key)
+		return
+	}
+
+	switch key {
+	case keyBackspace:
+		if t.pos == 0 {
+			return
+		}
+		t.eraseNPreviousChars(1)
+	case keyAltLeft:
+		// move left by a word.
+		t.pos -= t.countToLeftWord()
+		t.moveCursorToPos(t.pos)
+	case keyAltRight:
+		// move right by a word.
+		t.pos += t.countToRightWord()
+		t.moveCursorToPos(t.pos)
+	case keyLeft:
+		if t.pos == 0 {
+			return
+		}
+		t.pos--
+		t.moveCursorToPos(t.pos)
+	case keyRight:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos++
+		t.moveCursorToPos(t.pos)
+	case keyHome:
+		if t.pos == 0 {
+			return
+		}
+		t.pos = 0
+		t.moveCursorToPos(t.pos)
+	case keyEnd:
+		if t.pos == len(t.line) {
+			return
+		}
+		t.pos = len(t.line)
+		t.moveCursorToPos(t.pos)
+	case keyUp:
+		entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1)
+		if !ok {
+			return "", false
+		}
+		if t.historyIndex == -1 {
+			t.historyPending = string(t.line)
+		}
+		t.historyIndex++
+		runes := []rune(entry)
+		t.setLine(runes, len(runes))
+	case keyDown:
+		switch t.historyIndex {
+		case -1:
+			return
+		case 0:
+			runes := []rune(t.historyPending)
+			t.setLine(runes, len(runes))
+			t.historyIndex--
+		default:
+			entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1)
+			if ok {
+				t.historyIndex--
+				runes := []rune(entry)
+				t.setLine(runes, len(runes))
+			}
+		}
+	case keyEnter:
+		t.moveCursorToPos(len(t.line))
+		t.queue([]rune("\r\n"))
+		line = string(t.line)
+		ok = true
+		t.line = t.line[:0]
+		t.pos = 0
+		t.cursorX = 0
+		t.cursorY = 0
+		t.maxLine = 0
+	case keyDeleteWord:
+		// Delete zero or more spaces and then one or more characters.
+		t.eraseNPreviousChars(t.countToLeftWord())
+	case keyDeleteLine:
+		// Delete everything from the current cursor position to the
+		// end of line.
+		for i := t.pos; i < len(t.line); i++ {
+			t.queue(space)
+			t.advanceCursor(1)
+		}
+		t.line = t.line[:t.pos]
+		t.moveCursorToPos(t.pos)
+	case keyCtrlD:
+		// Erase the character under the current position.
+		// The EOF case when the line is empty is handled in
+		// readLine().
+		if t.pos < len(t.line) {
+			t.pos++
+			t.eraseNPreviousChars(1)
+		}
+	case keyCtrlU:
+		t.eraseNPreviousChars(t.pos)
+	case keyClearScreen:
+		// Erases the screen and moves the cursor to the home position.
+		t.queue([]rune("\x1b[2J\x1b[H"))
+		t.queue(t.prompt)
+		t.cursorX, t.cursorY = 0, 0
+		t.advanceCursor(visualLength(t.prompt))
+		t.setLine(t.line, t.pos)
+	default:
+		if t.AutoCompleteCallback != nil {
+			prefix := string(t.line[:t.pos])
+			suffix := string(t.line[t.pos:])
+
+			t.lock.Unlock()
+			newLine, newPos, completeOk := t.AutoCompleteCallback(prefix+suffix, len(prefix), key)
+			t.lock.Lock()
+
+			if completeOk {
+				t.setLine([]rune(newLine), utf8.RuneCount([]byte(newLine)[:newPos]))
+				return
+			}
+		}
+		if !isPrintable(key) {
+			return
+		}
+		if len(t.line) == maxLineLength {
+			return
+		}
+		t.addKeyToLine(key)
+	}
+	return
+}
+
+// addKeyToLine inserts the given key at the current position in the current
+// line.
+func (t *Terminal) addKeyToLine(key rune) {
+	if len(t.line) == cap(t.line) {
+		newLine := make([]rune, len(t.line), 2*(1+len(t.line)))
+		copy(newLine, t.line)
+		t.line = newLine
+	}
+	t.line = t.line[:len(t.line)+1]
+	copy(t.line[t.pos+1:], t.line[t.pos:])
+	t.line[t.pos] = key
+	if t.echo {
+		t.writeLine(t.line[t.pos:])
+	}
+	t.pos++
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) writeLine(line []rune) {
+	for len(line) != 0 {
+		remainingOnLine := t.termWidth - t.cursorX
+		todo := len(line)
+		if todo > remainingOnLine {
+			todo = remainingOnLine
+		}
+		t.queue(line[:todo])
+		t.advanceCursor(visualLength(line[:todo]))
+		line = line[todo:]
+	}
+}
+
+// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
+func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
+	for len(buf) > 0 {
+		i := bytes.IndexByte(buf, '\n')
+		todo := len(buf)
+		if i >= 0 {
+			todo = i
+		}
+
+		var nn int
+		nn, err = w.Write(buf[:todo])
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		buf = buf[todo:]
+
+		if i >= 0 {
+			if _, err = w.Write(crlf); err != nil {
+				return n, err
+			}
+			n += 1
+			buf = buf[1:]
+		}
+	}
+
+	return n, nil
+}
+
+func (t *Terminal) Write(buf []byte) (n int, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		// This is the easy case: there's nothing on the screen that we
+		// have to move out of the way.
+		return writeWithCRLF(t.c, buf)
+	}
+
+	// We have a prompt and possibly user input on the screen. We
+	// have to clear it first.
+	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
+	t.cursorX = 0
+	t.clearLineToRight()
+
+	for t.cursorY > 0 {
+		t.move(1 /* up */, 0, 0, 0)
+		t.cursorY--
+		t.clearLineToRight()
+	}
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+
+	if n, err = writeWithCRLF(t.c, buf); err != nil {
+		return
+	}
+
+	t.writeLine(t.prompt)
+	if t.echo {
+		t.writeLine(t.line)
+	}
+
+	t.moveCursorToPos(t.pos)
+
+	if _, err = t.c.Write(t.outBuf); err != nil {
+		return
+	}
+	t.outBuf = t.outBuf[:0]
+	return
+}
+
+// ReadPassword temporarily changes the prompt and reads a password, without
+// echo, from the terminal.
+func (t *Terminal) ReadPassword(prompt string) (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	oldPrompt := t.prompt
+	t.prompt = []rune(prompt)
+	t.echo = false
+
+	line, err = t.readLine()
+
+	t.prompt = oldPrompt
+	t.echo = true
+
+	return
+}
+
+// ReadLine returns a line of input from the terminal.
+func (t *Terminal) ReadLine() (line string, err error) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	return t.readLine()
+}
+
+func (t *Terminal) readLine() (line string, err error) {
+	// t.lock must be held at this point
+
+	if t.cursorX == 0 && t.cursorY == 0 {
+		t.writeLine(t.prompt)
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+	}
+
+	lineIsPasted := t.pasteActive
+
+	for {
+		rest := t.remainder
+		lineOk := false
+		for !lineOk {
+			var key rune
+			key, rest = bytesToKey(rest, t.pasteActive)
+			if key == utf8.RuneError {
+				break
+			}
+			if !t.pasteActive {
+				if key == keyCtrlD {
+					if len(t.line) == 0 {
+						return "", io.EOF
+					}
+				}
+				if key == keyPasteStart {
+					t.pasteActive = true
+					if len(t.line) == 0 {
+						lineIsPasted = true
+					}
+					continue
+				}
+			} else if key == keyPasteEnd {
+				t.pasteActive = false
+				continue
+			}
+			if !t.pasteActive {
+				lineIsPasted = false
+			}
+			line, lineOk = t.handleKey(key)
+		}
+		if len(rest) > 0 {
+			n := copy(t.inBuf[:], rest)
+			t.remainder = t.inBuf[:n]
+		} else {
+			t.remainder = nil
+		}
+		t.c.Write(t.outBuf)
+		t.outBuf = t.outBuf[:0]
+		if lineOk {
+			if t.echo {
+				t.historyIndex = -1
+				t.history.Add(line)
+			}
+			if lineIsPasted {
+				err = ErrPasteIndicator
+			}
+			return
+		}
+
+		// t.remainder is a slice at the beginning of t.inBuf
+		// containing a partial key sequence
+		readBuf := t.inBuf[len(t.remainder):]
+		var n int
+
+		t.lock.Unlock()
+		n, err = t.c.Read(readBuf)
+		t.lock.Lock()
+
+		if err != nil {
+			return
+		}
+
+		t.remainder = t.inBuf[:n+len(t.remainder)]
+	}
+}
+
+// SetPrompt sets the prompt to be used when reading subsequent lines.
+func (t *Terminal) SetPrompt(prompt string) {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	t.prompt = []rune(prompt)
+}
+
+func (t *Terminal) clearAndRepaintLinePlusNPrevious(numPrevLines int) {
+	// Move cursor to column zero at the start of the line.
+	t.move(t.cursorY, 0, t.cursorX, 0)
+	t.cursorX, t.cursorY = 0, 0
+	t.clearLineToRight()
+	for t.cursorY < numPrevLines {
+		// Move down a line
+		t.move(0, 1, 0, 0)
+		t.cursorY++
+		t.clearLineToRight()
+	}
+	// Move back to beginning.
+	t.move(t.cursorY, 0, 0, 0)
+	t.cursorX, t.cursorY = 0, 0
+
+	t.queue(t.prompt)
+	t.advanceCursor(visualLength(t.prompt))
+	t.writeLine(t.line)
+	t.moveCursorToPos(t.pos)
+}
+
+func (t *Terminal) SetSize(width, height int) error {
+	t.lock.Lock()
+	defer t.lock.Unlock()
+
+	if width == 0 {
+		width = 1
+	}
+
+	oldWidth := t.termWidth
+	t.termWidth, t.termHeight = width, height
+
+	switch {
+	case width == oldWidth:
+		// If the width didn't change then nothing else needs to be
+		// done.
+		return nil
+	case len(t.line) == 0 && t.cursorX == 0 && t.cursorY == 0:
+		// If there is nothing on current line and no prompt printed,
+		// just do nothing
+		return nil
+	case width < oldWidth:
+		// Some terminals (e.g. xterm) will truncate lines that were
+		// too long when shinking. Others, (e.g. gnome-terminal) will
+		// attempt to wrap them. For the former, repainting t.maxLine
+		// works great, but that behaviour goes badly wrong in the case
+		// of the latter because they have doubled every full line.
+
+		// We assume that we are working on a terminal that wraps lines
+		// and adjust the cursor position based on every previous line
+		// wrapping and turning into two. This causes the prompt on
+		// xterms to move upwards, which isn't great, but it avoids a
+		// huge mess with gnome-terminal.
+		if t.cursorX >= t.termWidth {
+			t.cursorX = t.termWidth - 1
+		}
+		t.cursorY *= 2
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine * 2)
+	case width > oldWidth:
+		// If the terminal expands then our position calculations will
+		// be wrong in the future because we think the cursor is
+		// |t.pos| chars into the string, but there will be a gap at
+		// the end of any wrapped line.
+		//
+		// But the position will actually be correct until we move, so
+		// we can move back to the beginning and repaint everything.
+		t.clearAndRepaintLinePlusNPrevious(t.maxLine)
+	}
+
+	_, err := t.c.Write(t.outBuf)
+	t.outBuf = t.outBuf[:0]
+	return err
+}
+
+type pasteIndicatorError struct{}
+
+func (pasteIndicatorError) Error() string {
+	return "terminal: ErrPasteIndicator not correctly handled"
+}
+
+// ErrPasteIndicator may be returned from ReadLine as the error, in addition
+// to valid line data. It indicates that bracketed paste mode is enabled and
+// that the returned line consists only of pasted data. Programs may wish to
+// interpret pasted data more literally than typed data.
+var ErrPasteIndicator = pasteIndicatorError{}
+
+// SetBracketedPasteMode requests that the terminal bracket paste operations
+// with markers. Not all terminals support this but, if it is supported, then
+// enabling this mode will stop any autocomplete callback from running due to
+// pastes. Additionally, any lines that are completely pasted will be returned
+// from ReadLine with the error set to ErrPasteIndicator.
+func (t *Terminal) SetBracketedPasteMode(on bool) {
+	if on {
+		io.WriteString(t.c, "\x1b[?2004h")
+	} else {
+		io.WriteString(t.c, "\x1b[?2004l")
+	}
+}
+
+// stRingBuffer is a ring buffer of strings.
+type stRingBuffer struct {
+	// entries contains max elements.
+	entries []string
+	max     int
+	// head contains the index of the element most recently added to the ring.
+	head int
+	// size contains the number of elements in the ring.
+	size int
+}
+
+func (s *stRingBuffer) Add(a string) {
+	if s.entries == nil {
+		const defaultNumEntries = 100
+		s.entries = make([]string, defaultNumEntries)
+		s.max = defaultNumEntries
+	}
+
+	s.head = (s.head + 1) % s.max
+	s.entries[s.head] = a
+	if s.size < s.max {
+		s.size++
+	}
+}
+
+// NthPreviousEntry returns the value passed to the nth previous call to Add.
+// If n is zero then the immediately prior value is returned, if one, then the
+// next most recent, and so on. If such an element doesn't exist then ok is
+// false.
+func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
+	if n >= s.size {
+		return "", false
+	}
+	index := s.head - n
+	if index < 0 {
+		index += s.max
+	}
+	return s.entries[index], true
+}
+
+// readPasswordLine reads from reader until it finds \n or io.EOF.
+// The slice returned does not include the \n.
+// readPasswordLine also ignores any \r it finds.
+func readPasswordLine(reader io.Reader) ([]byte, error) {
+	var buf [1]byte
+	var ret []byte
+
+	for {
+		n, err := reader.Read(buf[:])
+		if n > 0 {
+			switch buf[0] {
+			case '\n':
+				return ret, nil
+			case '\r':
+				// remove \r from passwords on Windows
+			default:
+				ret = append(ret, buf[0])
+			}
+			continue
+		}
+		if err != nil {
+			if err == io.EOF && len(ret) > 0 {
+				return ret, nil
+			}
+			return ret, err
+		}
+	}
+}

vendor/golang.org/x/crypto/ssh/terminal/util.go

@@ -0,0 +1,123 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux,!appengine netbsd openbsd
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal // import "golang.org/x/crypto/ssh/terminal"
+
+import (
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+// State contains the state of a terminal.
+type State struct {
+	termios syscall.Termios
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	var termios syscall.Termios
+	_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&termios)), 0, 0, 0)
+	return err == 0
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	var oldState State
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState.termios)), 0, 0, 0); err != 0 {
+		return nil, err
+	}
+
+	newState := oldState.termios
+	// This attempts to replicate the behaviour documented for cfmakeraw in
+	// the termios(3) manpage.
+	newState.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
+	newState.Oflag &^= syscall.OPOST
+	newState.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
+	newState.Cflag &^= syscall.CSIZE | syscall.PARENB
+	newState.Cflag |= syscall.CS8
+	newState.Cc[unix.VMIN] = 1
+	newState.Cc[unix.VTIME] = 0
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	var oldState State
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState.termios)), 0, 0, 0); err != 0 {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&state.termios)), 0, 0, 0); err != 0 {
+		return err
+	}
+	return nil
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	var dimensions [4]uint16
+
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(&dimensions)), 0, 0, 0); err != 0 {
+		return -1, -1, err
+	}
+	return int(dimensions[1]), int(dimensions[0]), nil
+}
+
+// passwordReader is an io.Reader that reads from a specific file descriptor.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return syscall.Read(int(r), buf)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	var oldState syscall.Termios
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlReadTermios, uintptr(unsafe.Pointer(&oldState)), 0, 0, 0); err != 0 {
+		return nil, err
+	}
+
+	newState := oldState
+	newState.Lflag &^= syscall.ECHO
+	newState.Lflag |= syscall.ICANON | syscall.ISIG
+	newState.Iflag |= syscall.ICRNL
+	if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&newState)), 0, 0, 0); err != 0 {
+		return nil, err
+	}
+
+	defer func() {
+		syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&oldState)), 0, 0, 0)
+	}()
+
+	return readPasswordLine(passwordReader(fd))
+}

vendor/golang.org/x/crypto/ssh/terminal/util_bsd.go

@@ -0,0 +1,12 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd netbsd openbsd
+
+package terminal
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TIOCGETA
+const ioctlWriteTermios = unix.TIOCSETA

vendor/golang.org/x/crypto/ssh/terminal/util_linux.go

@@ -0,0 +1,10 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package terminal
+
+import "golang.org/x/sys/unix"
+
+const ioctlReadTermios = unix.TCGETS
+const ioctlWriteTermios = unix.TCSETS

vendor/golang.org/x/crypto/ssh/terminal/util_plan9.go

@@ -0,0 +1,58 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal
+
+import (
+	"fmt"
+	"runtime"
+)
+
+type State struct{}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	return false
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: MakeRaw not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	return nil, fmt.Errorf("terminal: GetState not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	return fmt.Errorf("terminal: Restore not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	return 0, 0, fmt.Errorf("terminal: GetSize not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	return nil, fmt.Errorf("terminal: ReadPassword not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}

vendor/golang.org/x/crypto/ssh/terminal/util_solaris.go

@@ -0,0 +1,128 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build solaris
+
+package terminal // import "golang.org/x/crypto/ssh/terminal"
+
+import (
+	"golang.org/x/sys/unix"
+	"io"
+	"syscall"
+)
+
+// State contains the state of a terminal.
+type State struct {
+	state *unix.Termios
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	_, err := unix.IoctlGetTermio(fd, unix.TCGETA)
+	return err == nil
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
+	val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+	oldState := *val
+
+	newState := oldState
+	newState.Lflag &^= syscall.ECHO
+	newState.Lflag |= syscall.ICANON | syscall.ISIG
+	newState.Iflag |= syscall.ICRNL
+	err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState)
+	if err != nil {
+		return nil, err
+	}
+
+	defer unix.IoctlSetTermios(fd, unix.TCSETS, &oldState)
+
+	var buf [16]byte
+	var ret []byte
+	for {
+		n, err := syscall.Read(fd, buf[:])
+		if err != nil {
+			return nil, err
+		}
+		if n == 0 {
+			if len(ret) == 0 {
+				return nil, io.EOF
+			}
+			break
+		}
+		if buf[n-1] == '\n' {
+			n--
+		}
+		ret = append(ret, buf[:n]...)
+		if n < len(buf) {
+			break
+		}
+	}
+
+	return ret, nil
+}
+
+// MakeRaw puts the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+// see http://cr.illumos.org/~webrev/andy_js/1060/
+func MakeRaw(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+	oldTermios := *oldTermiosPtr
+
+	newTermios := oldTermios
+	newTermios.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
+	newTermios.Oflag &^= syscall.OPOST
+	newTermios.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
+	newTermios.Cflag &^= syscall.CSIZE | syscall.PARENB
+	newTermios.Cflag |= syscall.CS8
+	newTermios.Cc[unix.VMIN] = 1
+	newTermios.Cc[unix.VTIME] = 0
+
+	if err := unix.IoctlSetTermios(fd, unix.TCSETS, &newTermios); err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, oldState *State) error {
+	return unix.IoctlSetTermios(fd, unix.TCSETS, oldState.state)
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
+	if err != nil {
+		return nil, err
+	}
+
+	return &State{
+		state: oldTermiosPtr,
+	}, nil
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
+	if err != nil {
+		return 0, 0, err
+	}
+	return int(ws.Col), int(ws.Row), nil
+}

vendor/golang.org/x/crypto/ssh/terminal/util_windows.go

@@ -0,0 +1,102 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+// Package terminal provides support functions for dealing with terminals, as
+// commonly found on UNIX systems.
+//
+// Putting a terminal into raw mode is the most common requirement:
+//
+// 	oldState, err := terminal.MakeRaw(0)
+// 	if err != nil {
+// 	        panic(err)
+// 	}
+// 	defer terminal.Restore(0, oldState)
+package terminal
+
+import (
+	"golang.org/x/sys/windows"
+)
+
+type State struct {
+	mode uint32
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd int) bool {
+	var st uint32
+	err := windows.GetConsoleMode(windows.Handle(fd), &st)
+	return err == nil
+}
+
+// MakeRaw put the terminal connected to the given file descriptor into raw
+// mode and returns the previous state of the terminal so that it can be
+// restored.
+func MakeRaw(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	raw := st &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), raw); err != nil {
+		return nil, err
+	}
+	return &State{st}, nil
+}
+
+// GetState returns the current state of a terminal which may be useful to
+// restore the terminal after a signal.
+func GetState(fd int) (*State, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	return &State{st}, nil
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func Restore(fd int, state *State) error {
+	return windows.SetConsoleMode(windows.Handle(fd), state.mode)
+}
+
+// GetSize returns the dimensions of the given terminal.
+func GetSize(fd int) (width, height int, err error) {
+	var info windows.ConsoleScreenBufferInfo
+	if err := windows.GetConsoleScreenBufferInfo(windows.Handle(fd), &info); err != nil {
+		return 0, 0, err
+	}
+	return int(info.Size.X), int(info.Size.Y), nil
+}
+
+// passwordReader is an io.Reader that reads from a specific Windows HANDLE.
+type passwordReader int
+
+func (r passwordReader) Read(buf []byte) (int, error) {
+	return windows.Read(windows.Handle(r), buf)
+}
+
+// ReadPassword reads a line of input from a terminal without local echo.  This
+// is commonly used for inputting passwords and other sensitive data. The slice
+// returned does not include the \n.
+func ReadPassword(fd int) ([]byte, error) {
+	var st uint32
+	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
+		return nil, err
+	}
+	old := st
+
+	st &^= (windows.ENABLE_ECHO_INPUT)
+	st |= (windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	if err := windows.SetConsoleMode(windows.Handle(fd), st); err != nil {
+		return nil, err
+	}
+
+	defer func() {
+		windows.SetConsoleMode(windows.Handle(fd), old)
+	}()
+
+	return readPasswordLine(passwordReader(fd))
+}

vendor/golang.org/x/sys/windows/asm_windows_386.s

@@ -0,0 +1,13 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//
+// System calls for 386, Windows are implemented in runtime/syscall_windows.goc
+//
+
+TEXT ·getprocaddress(SB), 7, $0-8
+	JMP	syscall·getprocaddress(SB)
+
+TEXT ·loadlibrary(SB), 7, $0-4
+	JMP	syscall·loadlibrary(SB)

vendor/golang.org/x/sys/windows/asm_windows_amd64.s

@@ -0,0 +1,13 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//
+// System calls for amd64, Windows are implemented in runtime/syscall_windows.goc
+//
+
+TEXT ·getprocaddress(SB), 7, $0-32
+	JMP	syscall·getprocaddress(SB)
+
+TEXT ·loadlibrary(SB), 7, $0-8
+	JMP	syscall·loadlibrary(SB)

vendor/golang.org/x/sys/windows/dll_windows.go

@@ -0,0 +1,377 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+import (
+	"sync"
+	"sync/atomic"
+	"syscall"
+	"unsafe"
+)
+
+// DLLError describes reasons for DLL load failures.
+type DLLError struct {
+	Err     error
+	ObjName string
+	Msg     string
+}
+
+func (e *DLLError) Error() string { return e.Msg }
+
+// Implemented in runtime/syscall_windows.goc; we provide jumps to them in our assembly file.
+func loadlibrary(filename *uint16) (handle uintptr, err syscall.Errno)
+func getprocaddress(handle uintptr, procname *uint8) (proc uintptr, err syscall.Errno)
+
+// A DLL implements access to a single DLL.
+type DLL struct {
+	Name   string
+	Handle Handle
+}
+
+// LoadDLL loads DLL file into memory.
+//
+// Warning: using LoadDLL without an absolute path name is subject to
+// DLL preloading attacks. To safely load a system DLL, use LazyDLL
+// with System set to true, or use LoadLibraryEx directly.
+func LoadDLL(name string) (dll *DLL, err error) {
+	namep, err := UTF16PtrFromString(name)
+	if err != nil {
+		return nil, err
+	}
+	h, e := loadlibrary(namep)
+	if e != 0 {
+		return nil, &DLLError{
+			Err:     e,
+			ObjName: name,
+			Msg:     "Failed to load " + name + ": " + e.Error(),
+		}
+	}
+	d := &DLL{
+		Name:   name,
+		Handle: Handle(h),
+	}
+	return d, nil
+}
+
+// MustLoadDLL is like LoadDLL but panics if load operation failes.
+func MustLoadDLL(name string) *DLL {
+	d, e := LoadDLL(name)
+	if e != nil {
+		panic(e)
+	}
+	return d
+}
+
+// FindProc searches DLL d for procedure named name and returns *Proc
+// if found. It returns an error if search fails.
+func (d *DLL) FindProc(name string) (proc *Proc, err error) {
+	namep, err := BytePtrFromString(name)
+	if err != nil {
+		return nil, err
+	}
+	a, e := getprocaddress(uintptr(d.Handle), namep)
+	if e != 0 {
+		return nil, &DLLError{
+			Err:     e,
+			ObjName: name,
+			Msg:     "Failed to find " + name + " procedure in " + d.Name + ": " + e.Error(),
+		}
+	}
+	p := &Proc{
+		Dll:  d,
+		Name: name,
+		addr: a,
+	}
+	return p, nil
+}
+
+// MustFindProc is like FindProc but panics if search fails.
+func (d *DLL) MustFindProc(name string) *Proc {
+	p, e := d.FindProc(name)
+	if e != nil {
+		panic(e)
+	}
+	return p
+}
+
+// Release unloads DLL d from memory.
+func (d *DLL) Release() (err error) {
+	return FreeLibrary(d.Handle)
+}
+
+// A Proc implements access to a procedure inside a DLL.
+type Proc struct {
+	Dll  *DLL
+	Name string
+	addr uintptr
+}
+
+// Addr returns the address of the procedure represented by p.
+// The return value can be passed to Syscall to run the procedure.
+func (p *Proc) Addr() uintptr {
+	return p.addr
+}
+
+//go:uintptrescapes
+
+// Call executes procedure p with arguments a. It will panic, if more then 15 arguments
+// are supplied.
+//
+// The returned error is always non-nil, constructed from the result of GetLastError.
+// Callers must inspect the primary return value to decide whether an error occurred
+// (according to the semantics of the specific function being called) before consulting
+// the error. The error will be guaranteed to contain windows.Errno.
+func (p *Proc) Call(a ...uintptr) (r1, r2 uintptr, lastErr error) {
+	switch len(a) {
+	case 0:
+		return syscall.Syscall(p.Addr(), uintptr(len(a)), 0, 0, 0)
+	case 1:
+		return syscall.Syscall(p.Addr(), uintptr(len(a)), a[0], 0, 0)
+	case 2:
+		return syscall.Syscall(p.Addr(), uintptr(len(a)), a[0], a[1], 0)
+	case 3:
+		return syscall.Syscall(p.Addr(), uintptr(len(a)), a[0], a[1], a[2])
+	case 4:
+		return syscall.Syscall6(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], 0, 0)
+	case 5:
+		return syscall.Syscall6(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], 0)
+	case 6:
+		return syscall.Syscall6(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5])
+	case 7:
+		return syscall.Syscall9(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], 0, 0)
+	case 8:
+		return syscall.Syscall9(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], 0)
+	case 9:
+		return syscall.Syscall9(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8])
+	case 10:
+		return syscall.Syscall12(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], 0, 0)
+	case 11:
+		return syscall.Syscall12(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], 0)
+	case 12:
+		return syscall.Syscall12(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11])
+	case 13:
+		return syscall.Syscall15(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11], a[12], 0, 0)
+	case 14:
+		return syscall.Syscall15(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11], a[12], a[13], 0)
+	case 15:
+		return syscall.Syscall15(p.Addr(), uintptr(len(a)), a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7], a[8], a[9], a[10], a[11], a[12], a[13], a[14])
+	default:
+		panic("Call " + p.Name + " with too many arguments " + itoa(len(a)) + ".")
+	}
+}
+
+// A LazyDLL implements access to a single DLL.
+// It will delay the load of the DLL until the first
+// call to its Handle method or to one of its
+// LazyProc's Addr method.
+type LazyDLL struct {
+	Name string
+
+	// System determines whether the DLL must be loaded from the
+	// Windows System directory, bypassing the normal DLL search
+	// path.
+	System bool
+
+	mu  sync.Mutex
+	dll *DLL // non nil once DLL is loaded
+}
+
+// Load loads DLL file d.Name into memory. It returns an error if fails.
+// Load will not try to load DLL, if it is already loaded into memory.
+func (d *LazyDLL) Load() error {
+	// Non-racy version of:
+	// if d.dll != nil {
+	if atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&d.dll))) != nil {
+		return nil
+	}
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if d.dll != nil {
+		return nil
+	}
+
+	// kernel32.dll is special, since it's where LoadLibraryEx comes from.
+	// The kernel already special-cases its name, so it's always
+	// loaded from system32.
+	var dll *DLL
+	var err error
+	if d.Name == "kernel32.dll" {
+		dll, err = LoadDLL(d.Name)
+	} else {
+		dll, err = loadLibraryEx(d.Name, d.System)
+	}
+	if err != nil {
+		return err
+	}
+
+	// Non-racy version of:
+	// d.dll = dll
+	atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&d.dll)), unsafe.Pointer(dll))
+	return nil
+}
+
+// mustLoad is like Load but panics if search fails.
+func (d *LazyDLL) mustLoad() {
+	e := d.Load()
+	if e != nil {
+		panic(e)
+	}
+}
+
+// Handle returns d's module handle.
+func (d *LazyDLL) Handle() uintptr {
+	d.mustLoad()
+	return uintptr(d.dll.Handle)
+}
+
+// NewProc returns a LazyProc for accessing the named procedure in the DLL d.
+func (d *LazyDLL) NewProc(name string) *LazyProc {
+	return &LazyProc{l: d, Name: name}
+}
+
+// NewLazyDLL creates new LazyDLL associated with DLL file.
+func NewLazyDLL(name string) *LazyDLL {
+	return &LazyDLL{Name: name}
+}
+
+// NewLazySystemDLL is like NewLazyDLL, but will only
+// search Windows System directory for the DLL if name is
+// a base name (like "advapi32.dll").
+func NewLazySystemDLL(name string) *LazyDLL {
+	return &LazyDLL{Name: name, System: true}
+}
+
+// A LazyProc implements access to a procedure inside a LazyDLL.
+// It delays the lookup until the Addr method is called.
+type LazyProc struct {
+	Name string
+
+	mu   sync.Mutex
+	l    *LazyDLL
+	proc *Proc
+}
+
+// Find searches DLL for procedure named p.Name. It returns
+// an error if search fails. Find will not search procedure,
+// if it is already found and loaded into memory.
+func (p *LazyProc) Find() error {
+	// Non-racy version of:
+	// if p.proc == nil {
+	if atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&p.proc))) == nil {
+		p.mu.Lock()
+		defer p.mu.Unlock()
+		if p.proc == nil {
+			e := p.l.Load()
+			if e != nil {
+				return e
+			}
+			proc, e := p.l.dll.FindProc(p.Name)
+			if e != nil {
+				return e
+			}
+			// Non-racy version of:
+			// p.proc = proc
+			atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&p.proc)), unsafe.Pointer(proc))
+		}
+	}
+	return nil
+}
+
+// mustFind is like Find but panics if search fails.
+func (p *LazyProc) mustFind() {
+	e := p.Find()
+	if e != nil {
+		panic(e)
+	}
+}
+
+// Addr returns the address of the procedure represented by p.
+// The return value can be passed to Syscall to run the procedure.
+func (p *LazyProc) Addr() uintptr {
+	p.mustFind()
+	return p.proc.Addr()
+}
+
+//go:uintptrescapes
+
+// Call executes procedure p with arguments a. It will panic, if more then 15 arguments
+// are supplied.
+//
+// The returned error is always non-nil, constructed from the result of GetLastError.
+// Callers must inspect the primary return value to decide whether an error occurred
+// (according to the semantics of the specific function being called) before consulting
+// the error. The error will be guaranteed to contain windows.Errno.
+func (p *LazyProc) Call(a ...uintptr) (r1, r2 uintptr, lastErr error) {
+	p.mustFind()
+	return p.proc.Call(a...)
+}
+
+var canDoSearchSystem32Once struct {
+	sync.Once
+	v bool
+}
+
+func initCanDoSearchSystem32() {
+	// https://msdn.microsoft.com/en-us/library/ms684179(v=vs.85).aspx says:
+	// "Windows 7, Windows Server 2008 R2, Windows Vista, and Windows
+	// Server 2008: The LOAD_LIBRARY_SEARCH_* flags are available on
+	// systems that have KB2533623 installed. To determine whether the
+	// flags are available, use GetProcAddress to get the address of the
+	// AddDllDirectory, RemoveDllDirectory, or SetDefaultDllDirectories
+	// function. If GetProcAddress succeeds, the LOAD_LIBRARY_SEARCH_*
+	// flags can be used with LoadLibraryEx."
+	canDoSearchSystem32Once.v = (modkernel32.NewProc("AddDllDirectory").Find() == nil)
+}
+
+func canDoSearchSystem32() bool {
+	canDoSearchSystem32Once.Do(initCanDoSearchSystem32)
+	return canDoSearchSystem32Once.v
+}
+
+func isBaseName(name string) bool {
+	for _, c := range name {
+		if c == ':' || c == '/' || c == '\\' {
+			return false
+		}
+	}
+	return true
+}
+
+// loadLibraryEx wraps the Windows LoadLibraryEx function.
+//
+// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms684179(v=vs.85).aspx
+//
+// If name is not an absolute path, LoadLibraryEx searches for the DLL
+// in a variety of automatic locations unless constrained by flags.
+// See: https://msdn.microsoft.com/en-us/library/ff919712%28VS.85%29.aspx
+func loadLibraryEx(name string, system bool) (*DLL, error) {
+	loadDLL := name
+	var flags uintptr
+	if system {
+		if canDoSearchSystem32() {
+			const LOAD_LIBRARY_SEARCH_SYSTEM32 = 0x00000800
+			flags = LOAD_LIBRARY_SEARCH_SYSTEM32
+		} else if isBaseName(name) {
+			// WindowsXP or unpatched Windows machine
+			// trying to load "foo.dll" out of the system
+			// folder, but LoadLibraryEx doesn't support
+			// that yet on their system, so emulate it.
+			windir, _ := Getenv("WINDIR") // old var; apparently works on XP
+			if windir == "" {
+				return nil, errString("%WINDIR% not defined")
+			}
+			loadDLL = windir + "\\System32\\" + name
+		}
+	}
+	h, err := LoadLibraryEx(loadDLL, 0, flags)
+	if err != nil {
+		return nil, err
+	}
+	return &DLL{Name: name, Handle: h}, nil
+}
+
+type errString string
+
+func (s errString) Error() string { return string(s) }

vendor/golang.org/x/sys/windows/env_unset.go

@@ -0,0 +1,15 @@
+// Copyright 2014 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+// +build go1.4
+
+package windows
+
+import "syscall"
+
+func Unsetenv(key string) error {
+	// This was added in Go 1.4.
+	return syscall.Unsetenv(key)
+}

vendor/golang.org/x/sys/windows/env_windows.go

@@ -0,0 +1,25 @@
+// Copyright 2010 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Windows environment variables.
+
+package windows
+
+import "syscall"
+
+func Getenv(key string) (value string, found bool) {
+	return syscall.Getenv(key)
+}
+
+func Setenv(key, value string) error {
+	return syscall.Setenv(key, value)
+}
+
+func Clearenv() {
+	syscall.Clearenv()
+}
+
+func Environ() []string {
+	return syscall.Environ()
+}

vendor/golang.org/x/sys/windows/eventlog.go

@@ -0,0 +1,20 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package windows
+
+const (
+	EVENTLOG_SUCCESS          = 0
+	EVENTLOG_ERROR_TYPE       = 1
+	EVENTLOG_WARNING_TYPE     = 2
+	EVENTLOG_INFORMATION_TYPE = 4
+	EVENTLOG_AUDIT_SUCCESS    = 8
+	EVENTLOG_AUDIT_FAILURE    = 16
+)
+
+//sys	RegisterEventSource(uncServerName *uint16, sourceName *uint16) (handle Handle, err error) [failretval==0] = advapi32.RegisterEventSourceW
+//sys	DeregisterEventSource(handle Handle) (err error) = advapi32.DeregisterEventSource
+//sys	ReportEvent(log Handle, etype uint16, category uint16, eventId uint32, usrSId uintptr, numStrings uint16, dataSize uint32, strings **uint16, rawData *byte) (err error) = advapi32.ReportEventW

vendor/golang.org/x/sys/windows/exec_windows.go

@@ -0,0 +1,97 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Fork, exec, wait, etc.
+
+package windows
+
+// EscapeArg rewrites command line argument s as prescribed
+// in http://msdn.microsoft.com/en-us/library/ms880421.
+// This function returns "" (2 double quotes) if s is empty.
+// Alternatively, these transformations are done:
+// - every back slash (\) is doubled, but only if immediately
+//   followed by double quote (");
+// - every double quote (") is escaped by back slash (\);
+// - finally, s is wrapped with double quotes (arg -> "arg"),
+//   but only if there is space or tab inside s.
+func EscapeArg(s string) string {
+	if len(s) == 0 {
+		return "\"\""
+	}
+	n := len(s)
+	hasSpace := false
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"', '\\':
+			n++
+		case ' ', '\t':
+			hasSpace = true
+		}
+	}
+	if hasSpace {
+		n += 2
+	}
+	if n == len(s) {
+		return s
+	}
+
+	qs := make([]byte, n)
+	j := 0
+	if hasSpace {
+		qs[j] = '"'
+		j++
+	}
+	slashes := 0
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		default:
+			slashes = 0
+			qs[j] = s[i]
+		case '\\':
+			slashes++
+			qs[j] = s[i]
+		case '"':
+			for ; slashes > 0; slashes-- {
+				qs[j] = '\\'
+				j++
+			}
+			qs[j] = '\\'
+			j++
+			qs[j] = s[i]
+		}
+		j++
+	}
+	if hasSpace {
+		for ; slashes > 0; slashes-- {
+			qs[j] = '\\'
+			j++
+		}
+		qs[j] = '"'
+		j++
+	}
+	return string(qs[:j])
+}
+
+func CloseOnExec(fd Handle) {
+	SetHandleInformation(Handle(fd), HANDLE_FLAG_INHERIT, 0)
+}
+
+// FullPath retrieves the full path of the specified file.
+func FullPath(name string) (path string, err error) {
+	p, err := UTF16PtrFromString(name)
+	if err != nil {
+		return "", err
+	}
+	n := uint32(100)
+	for {
+		buf := make([]uint16, n)
+		n, err = GetFullPathName(p, uint32(len(buf)), &buf[0], nil)
+		if err != nil {
+			return "", err
+		}
+		if n <= uint32(len(buf)) {
+			return UTF16ToString(buf[:n]), nil
+		}
+	}
+}

vendor/golang.org/x/sys/windows/memory_windows.go

@@ -0,0 +1,26 @@
+// Copyright 2017 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+const (
+	MEM_COMMIT      = 0x00001000
+	MEM_RESERVE     = 0x00002000
+	MEM_DECOMMIT    = 0x00004000
+	MEM_RELEASE     = 0x00008000
+	MEM_RESET       = 0x00080000
+	MEM_TOP_DOWN    = 0x00100000
+	MEM_WRITE_WATCH = 0x00200000
+	MEM_PHYSICAL    = 0x00400000
+	MEM_RESET_UNDO  = 0x01000000
+	MEM_LARGE_PAGES = 0x20000000
+
+	PAGE_NOACCESS          = 0x01
+	PAGE_READONLY          = 0x02
+	PAGE_READWRITE         = 0x04
+	PAGE_WRITECOPY         = 0x08
+	PAGE_EXECUTE_READ      = 0x20
+	PAGE_EXECUTE_READWRITE = 0x40
+	PAGE_EXECUTE_WRITECOPY = 0x80
+)

vendor/golang.org/x/sys/windows/mksyscall.go

@@ -0,0 +1,7 @@
+// Copyright 2009 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go eventlog.go service.go syscall_windows.go security_windows.go

vendor/golang.org/x/sys/windows/race.go

@@ -0,0 +1,30 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows,race
+
+package windows
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+const raceenabled = true
+
+func raceAcquire(addr unsafe.Pointer) {
+	runtime.RaceAcquire(addr)
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+	runtime.RaceReleaseMerge(addr)
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+	runtime.RaceReadRange(addr, len)
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+	runtime.RaceWriteRange(addr, len)
+}

vendor/golang.org/x/sys/windows/race0.go

@@ -0,0 +1,25 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows,!race
+
+package windows
+
+import (
+	"unsafe"
+)
+
+const raceenabled = false
+
+func raceAcquire(addr unsafe.Pointer) {
+}
+
+func raceReleaseMerge(addr unsafe.Pointer) {
+}
+
+func raceReadRange(addr unsafe.Pointer, len int) {
+}
+
+func raceWriteRange(addr unsafe.Pointer, len int) {
+}

vendor/golang.org/x/sys/windows/registry/key.go

@@ -0,0 +1,200 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+// Package registry provides access to the Windows registry.
+//
+// Here is a simple example, opening a registry key and reading a string value from it.
+//
+//	k, err := registry.OpenKey(registry.LOCAL_MACHINE, `SOFTWARE\Microsoft\Windows NT\CurrentVersion`, registry.QUERY_VALUE)
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//	defer k.Close()
+//
+//	s, _, err := k.GetStringValue("SystemRoot")
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//	fmt.Printf("Windows system root is %q\n", s)
+//
+package registry
+
+import (
+	"io"
+	"syscall"
+	"time"
+)
+
+const (
+	// Registry key security and access rights.
+	// See https://msdn.microsoft.com/en-us/library/windows/desktop/ms724878.aspx
+	// for details.
+	ALL_ACCESS         = 0xf003f
+	CREATE_LINK        = 0x00020
+	CREATE_SUB_KEY     = 0x00004
+	ENUMERATE_SUB_KEYS = 0x00008
+	EXECUTE            = 0x20019
+	NOTIFY             = 0x00010
+	QUERY_VALUE        = 0x00001
+	READ               = 0x20019
+	SET_VALUE          = 0x00002
+	WOW64_32KEY        = 0x00200
+	WOW64_64KEY        = 0x00100
+	WRITE              = 0x20006
+)
+
+// Key is a handle to an open Windows registry key.
+// Keys can be obtained by calling OpenKey; there are
+// also some predefined root keys such as CURRENT_USER.
+// Keys can be used directly in the Windows API.
+type Key syscall.Handle
+
+const (
+	// Windows defines some predefined root keys that are always open.
+	// An application can use these keys as entry points to the registry.
+	// Normally these keys are used in OpenKey to open new keys,
+	// but they can also be used anywhere a Key is required.
+	CLASSES_ROOT     = Key(syscall.HKEY_CLASSES_ROOT)
+	CURRENT_USER     = Key(syscall.HKEY_CURRENT_USER)
+	LOCAL_MACHINE    = Key(syscall.HKEY_LOCAL_MACHINE)
+	USERS            = Key(syscall.HKEY_USERS)
+	CURRENT_CONFIG   = Key(syscall.HKEY_CURRENT_CONFIG)
+	PERFORMANCE_DATA = Key(syscall.HKEY_PERFORMANCE_DATA)
+)
+
+// Close closes open key k.
+func (k Key) Close() error {
+	return syscall.RegCloseKey(syscall.Handle(k))
+}
+
+// OpenKey opens a new key with path name relative to key k.
+// It accepts any open key, including CURRENT_USER and others,
+// and returns the new key and an error.
+// The access parameter specifies desired access rights to the
+// key to be opened.
+func OpenKey(k Key, path string, access uint32) (Key, error) {
+	p, err := syscall.UTF16PtrFromString(path)
+	if err != nil {
+		return 0, err
+	}
+	var subkey syscall.Handle
+	err = syscall.RegOpenKeyEx(syscall.Handle(k), p, 0, access, &subkey)
+	if err != nil {
+		return 0, err
+	}
+	return Key(subkey), nil
+}
+
+// OpenRemoteKey opens a predefined registry key on another
+// computer pcname. The key to be opened is specified by k, but
+// can only be one of LOCAL_MACHINE, PERFORMANCE_DATA or USERS.
+// If pcname is "", OpenRemoteKey returns local computer key.
+func OpenRemoteKey(pcname string, k Key) (Key, error) {
+	var err error
+	var p *uint16
+	if pcname != "" {
+		p, err = syscall.UTF16PtrFromString(`\\` + pcname)
+		if err != nil {
+			return 0, err
+		}
+	}
+	var remoteKey syscall.Handle
+	err = regConnectRegistry(p, syscall.Handle(k), &remoteKey)
+	if err != nil {
+		return 0, err
+	}
+	return Key(remoteKey), nil
+}
+
+// ReadSubKeyNames returns the names of subkeys of key k.
+// The parameter n controls the number of returned names,
+// analogous to the way os.File.Readdirnames works.
+func (k Key) ReadSubKeyNames(n int) ([]string, error) {
+	ki, err := k.Stat()
+	if err != nil {
+		return nil, err
+	}
+	names := make([]string, 0, ki.SubKeyCount)
+	buf := make([]uint16, ki.MaxSubKeyLen+1) // extra room for terminating zero byte
+loopItems:
+	for i := uint32(0); ; i++ {
+		if n > 0 {
+			if len(names) == n {
+				return names, nil
+			}
+		}
+		l := uint32(len(buf))
+		for {
+			err := syscall.RegEnumKeyEx(syscall.Handle(k), i, &buf[0], &l, nil, nil, nil, nil)
+			if err == nil {
+				break
+			}
+			if err == syscall.ERROR_MORE_DATA {
+				// Double buffer size and try again.
+				l = uint32(2 * len(buf))
+				buf = make([]uint16, l)
+				continue
+			}
+			if err == _ERROR_NO_MORE_ITEMS {
+				break loopItems
+			}
+			return names, err
+		}
+		names = append(names, syscall.UTF16ToString(buf[:l]))
+	}
+	if n > len(names) {
+		return names, io.EOF
+	}
+	return names, nil
+}
+
+// CreateKey creates a key named path under open key k.
+// CreateKey returns the new key and a boolean flag that reports
+// whether the key already existed.
+// The access parameter specifies the access rights for the key
+// to be created.
+func CreateKey(k Key, path string, access uint32) (newk Key, openedExisting bool, err error) {
+	var h syscall.Handle
+	var d uint32
+	err = regCreateKeyEx(syscall.Handle(k), syscall.StringToUTF16Ptr(path),
+		0, nil, _REG_OPTION_NON_VOLATILE, access, nil, &h, &d)
+	if err != nil {
+		return 0, false, err
+	}
+	return Key(h), d == _REG_OPENED_EXISTING_KEY, nil
+}
+
+// DeleteKey deletes the subkey path of key k and its values.
+func DeleteKey(k Key, path string) error {
+	return regDeleteKey(syscall.Handle(k), syscall.StringToUTF16Ptr(path))
+}
+
+// A KeyInfo describes the statistics of a key. It is returned by Stat.
+type KeyInfo struct {
+	SubKeyCount     uint32
+	MaxSubKeyLen    uint32 // size of the key's subkey with the longest name, in Unicode characters, not including the terminating zero byte
+	ValueCount      uint32
+	MaxValueNameLen uint32 // size of the key's longest value name, in Unicode characters, not including the terminating zero byte
+	MaxValueLen     uint32 // longest data component among the key's values, in bytes
+	lastWriteTime   syscall.Filetime
+}
+
+// ModTime returns the key's last write time.
+func (ki *KeyInfo) ModTime() time.Time {
+	return time.Unix(0, ki.lastWriteTime.Nanoseconds())
+}
+
+// Stat retrieves information about the open key k.
+func (k Key) Stat() (*KeyInfo, error) {
+	var ki KeyInfo
+	err := syscall.RegQueryInfoKey(syscall.Handle(k), nil, nil, nil,
+		&ki.SubKeyCount, &ki.MaxSubKeyLen, nil, &ki.ValueCount,
+		&ki.MaxValueNameLen, &ki.MaxValueLen, nil, &ki.lastWriteTime)
+	if err != nil {
+		return nil, err
+	}
+	return &ki, nil
+}

vendor/golang.org/x/sys/windows/registry/mksyscall.go

@@ -0,0 +1,7 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package registry
+
+//go:generate go run $GOROOT/src/syscall/mksyscall_windows.go -output zsyscall_windows.go syscall.go

vendor/golang.org/x/sys/windows/registry/syscall.go

@@ -0,0 +1,32 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package registry
+
+import "syscall"
+
+const (
+	_REG_OPTION_NON_VOLATILE = 0
+
+	_REG_CREATED_NEW_KEY     = 1
+	_REG_OPENED_EXISTING_KEY = 2
+
+	_ERROR_NO_MORE_ITEMS syscall.Errno = 259
+)
+
+func LoadRegLoadMUIString() error {
+	return procRegLoadMUIStringW.Find()
+}
+
+//sys	regCreateKeyEx(key syscall.Handle, subkey *uint16, reserved uint32, class *uint16, options uint32, desired uint32, sa *syscall.SecurityAttributes, result *syscall.Handle, disposition *uint32) (regerrno error) = advapi32.RegCreateKeyExW
+//sys	regDeleteKey(key syscall.Handle, subkey *uint16) (regerrno error) = advapi32.RegDeleteKeyW
+//sys	regSetValueEx(key syscall.Handle, valueName *uint16, reserved uint32, vtype uint32, buf *byte, bufsize uint32) (regerrno error) = advapi32.RegSetValueExW
+//sys	regEnumValue(key syscall.Handle, index uint32, name *uint16, nameLen *uint32, reserved *uint32, valtype *uint32, buf *byte, buflen *uint32) (regerrno error) = advapi32.RegEnumValueW
+//sys	regDeleteValue(key syscall.Handle, name *uint16) (regerrno error) = advapi32.RegDeleteValueW
+//sys   regLoadMUIString(key syscall.Handle, name *uint16, buf *uint16, buflen uint32, buflenCopied *uint32, flags uint32, dir *uint16) (regerrno error) = advapi32.RegLoadMUIStringW
+//sys	regConnectRegistry(machinename *uint16, key syscall.Handle, result *syscall.Handle) (regerrno error) = advapi32.RegConnectRegistryW
+
+//sys	expandEnvironmentStrings(src *uint16, dst *uint16, size uint32) (n uint32, err error) = kernel32.ExpandEnvironmentStringsW

vendor/golang.org/x/sys/windows/registry/value.go

@@ -0,0 +1,384 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package registry
+
+import (
+	"errors"
+	"io"
+	"syscall"
+	"unicode/utf16"
+	"unsafe"
+)
+
+const (
+	// Registry value types.
+	NONE                       = 0
+	SZ                         = 1
+	EXPAND_SZ                  = 2
+	BINARY                     = 3
+	DWORD                      = 4
+	DWORD_BIG_ENDIAN           = 5
+	LINK                       = 6
+	MULTI_SZ                   = 7
+	RESOURCE_LIST              = 8
+	FULL_RESOURCE_DESCRIPTOR   = 9
+	RESOURCE_REQUIREMENTS_LIST = 10
+	QWORD                      = 11
+)
+
+var (
+	// ErrShortBuffer is returned when the buffer was too short for the operation.
+	ErrShortBuffer = syscall.ERROR_MORE_DATA
+
+	// ErrNotExist is returned when a registry key or value does not exist.
+	ErrNotExist = syscall.ERROR_FILE_NOT_FOUND
+
+	// ErrUnexpectedType is returned by Get*Value when the value's type was unexpected.
+	ErrUnexpectedType = errors.New("unexpected key value type")
+)
+
+// GetValue retrieves the type and data for the specified value associated
+// with an open key k. It fills up buffer buf and returns the retrieved
+// byte count n. If buf is too small to fit the stored value it returns
+// ErrShortBuffer error along with the required buffer size n.
+// If no buffer is provided, it returns true and actual buffer size n.
+// If no buffer is provided, GetValue returns the value's type only.
+// If the value does not exist, the error returned is ErrNotExist.
+//
+// GetValue is a low level function. If value's type is known, use the appropriate
+// Get*Value function instead.
+func (k Key) GetValue(name string, buf []byte) (n int, valtype uint32, err error) {
+	pname, err := syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return 0, 0, err
+	}
+	var pbuf *byte
+	if len(buf) > 0 {
+		pbuf = (*byte)(unsafe.Pointer(&buf[0]))
+	}
+	l := uint32(len(buf))
+	err = syscall.RegQueryValueEx(syscall.Handle(k), pname, nil, &valtype, pbuf, &l)
+	if err != nil {
+		return int(l), valtype, err
+	}
+	return int(l), valtype, nil
+}
+
+func (k Key) getValue(name string, buf []byte) (date []byte, valtype uint32, err error) {
+	p, err := syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return nil, 0, err
+	}
+	var t uint32
+	n := uint32(len(buf))
+	for {
+		err = syscall.RegQueryValueEx(syscall.Handle(k), p, nil, &t, (*byte)(unsafe.Pointer(&buf[0])), &n)
+		if err == nil {
+			return buf[:n], t, nil
+		}
+		if err != syscall.ERROR_MORE_DATA {
+			return nil, 0, err
+		}
+		if n <= uint32(len(buf)) {
+			return nil, 0, err
+		}
+		buf = make([]byte, n)
+	}
+}
+
+// GetStringValue retrieves the string value for the specified
+// value name associated with an open key k. It also returns the value's type.
+// If value does not exist, GetStringValue returns ErrNotExist.
+// If value is not SZ or EXPAND_SZ, it will return the correct value
+// type and ErrUnexpectedType.
+func (k Key) GetStringValue(name string) (val string, valtype uint32, err error) {
+	data, typ, err2 := k.getValue(name, make([]byte, 64))
+	if err2 != nil {
+		return "", typ, err2
+	}
+	switch typ {
+	case SZ, EXPAND_SZ:
+	default:
+		return "", typ, ErrUnexpectedType
+	}
+	if len(data) == 0 {
+		return "", typ, nil
+	}
+	u := (*[1 << 29]uint16)(unsafe.Pointer(&data[0]))[:]
+	return syscall.UTF16ToString(u), typ, nil
+}
+
+// GetMUIStringValue retrieves the localized string value for
+// the specified value name associated with an open key k.
+// If the value name doesn't exist or the localized string value
+// can't be resolved, GetMUIStringValue returns ErrNotExist.
+// GetMUIStringValue panics if the system doesn't support
+// regLoadMUIString; use LoadRegLoadMUIString to check if
+// regLoadMUIString is supported before calling this function.
+func (k Key) GetMUIStringValue(name string) (string, error) {
+	pname, err := syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return "", err
+	}
+
+	buf := make([]uint16, 1024)
+	var buflen uint32
+	var pdir *uint16
+
+	err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir)
+	if err == syscall.ERROR_FILE_NOT_FOUND { // Try fallback path
+
+		// Try to resolve the string value using the system directory as
+		// a DLL search path; this assumes the string value is of the form
+		// @[path]\dllname,-strID but with no path given, e.g. @tzres.dll,-320.
+
+		// This approach works with tzres.dll but may have to be revised
+		// in the future to allow callers to provide custom search paths.
+
+		var s string
+		s, err = ExpandString("%SystemRoot%\\system32\\")
+		if err != nil {
+			return "", err
+		}
+		pdir, err = syscall.UTF16PtrFromString(s)
+		if err != nil {
+			return "", err
+		}
+
+		err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir)
+	}
+
+	for err == syscall.ERROR_MORE_DATA { // Grow buffer if needed
+		if buflen <= uint32(len(buf)) {
+			break // Buffer not growing, assume race; break
+		}
+		buf = make([]uint16, buflen)
+		err = regLoadMUIString(syscall.Handle(k), pname, &buf[0], uint32(len(buf)), &buflen, 0, pdir)
+	}
+
+	if err != nil {
+		return "", err
+	}
+
+	return syscall.UTF16ToString(buf), nil
+}
+
+// ExpandString expands environment-variable strings and replaces
+// them with the values defined for the current user.
+// Use ExpandString to expand EXPAND_SZ strings.
+func ExpandString(value string) (string, error) {
+	if value == "" {
+		return "", nil
+	}
+	p, err := syscall.UTF16PtrFromString(value)
+	if err != nil {
+		return "", err
+	}
+	r := make([]uint16, 100)
+	for {
+		n, err := expandEnvironmentStrings(p, &r[0], uint32(len(r)))
+		if err != nil {
+			return "", err
+		}
+		if n <= uint32(len(r)) {
+			u := (*[1 << 29]uint16)(unsafe.Pointer(&r[0]))[:]
+			return syscall.UTF16ToString(u), nil
+		}
+		r = make([]uint16, n)
+	}
+}
+
+// GetStringsValue retrieves the []string value for the specified
+// value name associated with an open key k. It also returns the value's type.
+// If value does not exist, GetStringsValue returns ErrNotExist.
+// If value is not MULTI_SZ, it will return the correct value
+// type and ErrUnexpectedType.
+func (k Key) GetStringsValue(name string) (val []string, valtype uint32, err error) {
+	data, typ, err2 := k.getValue(name, make([]byte, 64))
+	if err2 != nil {
+		return nil, typ, err2
+	}
+	if typ != MULTI_SZ {
+		return nil, typ, ErrUnexpectedType
+	}
+	if len(data) == 0 {
+		return nil, typ, nil
+	}
+	p := (*[1 << 29]uint16)(unsafe.Pointer(&data[0]))[:len(data)/2]
+	if len(p) == 0 {
+		return nil, typ, nil
+	}
+	if p[len(p)-1] == 0 {
+		p = p[:len(p)-1] // remove terminating null
+	}
+	val = make([]string, 0, 5)
+	from := 0
+	for i, c := range p {
+		if c == 0 {
+			val = append(val, string(utf16.Decode(p[from:i])))
+			from = i + 1
+		}
+	}
+	return val, typ, nil
+}
+
+// GetIntegerValue retrieves the integer value for the specified
+// value name associated with an open key k. It also returns the value's type.
+// If value does not exist, GetIntegerValue returns ErrNotExist.
+// If value is not DWORD or QWORD, it will return the correct value
+// type and ErrUnexpectedType.
+func (k Key) GetIntegerValue(name string) (val uint64, valtype uint32, err error) {
+	data, typ, err2 := k.getValue(name, make([]byte, 8))
+	if err2 != nil {
+		return 0, typ, err2
+	}
+	switch typ {
+	case DWORD:
+		if len(data) != 4 {
+			return 0, typ, errors.New("DWORD value is not 4 bytes long")
+		}
+		return uint64(*(*uint32)(unsafe.Pointer(&data[0]))), DWORD, nil
+	case QWORD:
+		if len(data) != 8 {
+			return 0, typ, errors.New("QWORD value is not 8 bytes long")
+		}
+		return uint64(*(*uint64)(unsafe.Pointer(&data[0]))), QWORD, nil
+	default:
+		return 0, typ, ErrUnexpectedType
+	}
+}
+
+// GetBinaryValue retrieves the binary value for the specified
+// value name associated with an open key k. It also returns the value's type.
+// If value does not exist, GetBinaryValue returns ErrNotExist.
+// If value is not BINARY, it will return the correct value
+// type and ErrUnexpectedType.
+func (k Key) GetBinaryValue(name string) (val []byte, valtype uint32, err error) {
+	data, typ, err2 := k.getValue(name, make([]byte, 64))
+	if err2 != nil {
+		return nil, typ, err2
+	}
+	if typ != BINARY {
+		return nil, typ, ErrUnexpectedType
+	}
+	return data, typ, nil
+}
+
+func (k Key) setValue(name string, valtype uint32, data []byte) error {
+	p, err := syscall.UTF16PtrFromString(name)
+	if err != nil {
+		return err
+	}
+	if len(data) == 0 {
+		return regSetValueEx(syscall.Handle(k), p, 0, valtype, nil, 0)
+	}
+	return regSetValueEx(syscall.Handle(k), p, 0, valtype, &data[0], uint32(len(data)))
+}
+
+// SetDWordValue sets the data and type of a name value
+// under key k to value and DWORD.
+func (k Key) SetDWordValue(name string, value uint32) error {
+	return k.setValue(name, DWORD, (*[4]byte)(unsafe.Pointer(&value))[:])
+}
+
+// SetQWordValue sets the data and type of a name value
+// under key k to value and QWORD.
+func (k Key) SetQWordValue(name string, value uint64) error {
+	return k.setValue(name, QWORD, (*[8]byte)(unsafe.Pointer(&value))[:])
+}
+
+func (k Key) setStringValue(name string, valtype uint32, value string) error {
+	v, err := syscall.UTF16FromString(value)
+	if err != nil {
+		return err
+	}
+	buf := (*[1 << 29]byte)(unsafe.Pointer(&v[0]))[:len(v)*2]
+	return k.setValue(name, valtype, buf)
+}
+
+// SetStringValue sets the data and type of a name value
+// under key k to value and SZ. The value must not contain a zero byte.
+func (k Key) SetStringValue(name, value string) error {
+	return k.setStringValue(name, SZ, value)
+}
+
+// SetExpandStringValue sets the data and type of a name value
+// under key k to value and EXPAND_SZ. The value must not contain a zero byte.
+func (k Key) SetExpandStringValue(name, value string) error {
+	return k.setStringValue(name, EXPAND_SZ, value)
+}
+
+// SetStringsValue sets the data and type of a name value
+// under key k to value and MULTI_SZ. The value strings
+// must not contain a zero byte.
+func (k Key) SetStringsValue(name string, value []string) error {
+	ss := ""
+	for _, s := range value {
+		for i := 0; i < len(s); i++ {
+			if s[i] == 0 {
+				return errors.New("string cannot have 0 inside")
+			}
+		}
+		ss += s + "\x00"
+	}
+	v := utf16.Encode([]rune(ss + "\x00"))
+	buf := (*[1 << 29]byte)(unsafe.Pointer(&v[0]))[:len(v)*2]
+	return k.setValue(name, MULTI_SZ, buf)
+}
+
+// SetBinaryValue sets the data and type of a name value
+// under key k to value and BINARY.
+func (k Key) SetBinaryValue(name string, value []byte) error {
+	return k.setValue(name, BINARY, value)
+}
+
+// DeleteValue removes a named value from the key k.
+func (k Key) DeleteValue(name string) error {
+	return regDeleteValue(syscall.Handle(k), syscall.StringToUTF16Ptr(name))
+}
+
+// ReadValueNames returns the value names of key k.
+// The parameter n controls the number of returned names,
+// analogous to the way os.File.Readdirnames works.
+func (k Key) ReadValueNames(n int) ([]string, error) {
+	ki, err := k.Stat()
+	if err != nil {
+		return nil, err
+	}
+	names := make([]string, 0, ki.ValueCount)
+	buf := make([]uint16, ki.MaxValueNameLen+1) // extra room for terminating null character
+loopItems:
+	for i := uint32(0); ; i++ {
+		if n > 0 {
+			if len(names) == n {
+				return names, nil
+			}
+		}
+		l := uint32(len(buf))
+		for {
+			err := regEnumValue(syscall.Handle(k), i, &buf[0], &l, nil, nil, nil, nil)
+			if err == nil {
+				break
+			}
+			if err == syscall.ERROR_MORE_DATA {
+				// Double buffer size and try again.
+				l = uint32(2 * len(buf))
+				buf = make([]uint16, l)
+				continue
+			}
+			if err == _ERROR_NO_MORE_ITEMS {
+				break loopItems
+			}
+			return names, err
+		}
+		names = append(names, syscall.UTF16ToString(buf[:l]))
+	}
+	if n > len(names) {
+		return names, io.EOF
+	}
+	return names, nil
+}

vendor/golang.org/x/sys/windows/registry/zsyscall_windows.go

@@ -0,0 +1,120 @@
+// MACHINE GENERATED BY 'go generate' COMMAND; DO NOT EDIT
+
+package registry
+
+import (
+	"syscall"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+var _ unsafe.Pointer
+
+// Do the interface allocations only once for common
+// Errno values.
+const (
+	errnoERROR_IO_PENDING = 997
+)
+
+var (
+	errERROR_IO_PENDING error = syscall.Errno(errnoERROR_IO_PENDING)
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case errnoERROR_IO_PENDING:
+		return errERROR_IO_PENDING
+	}
+	// TODO: add more here, after collecting data on the common
+	// error values see on Windows. (perhaps when running
+	// all.bat?)
+	return e
+}
+
+var (
+	modadvapi32 = windows.NewLazySystemDLL("advapi32.dll")
+	modkernel32 = windows.NewLazySystemDLL("kernel32.dll")
+
+	procRegCreateKeyExW           = modadvapi32.NewProc("RegCreateKeyExW")
+	procRegDeleteKeyW             = modadvapi32.NewProc("RegDeleteKeyW")
+	procRegSetValueExW            = modadvapi32.NewProc("RegSetValueExW")
+	procRegEnumValueW             = modadvapi32.NewProc("RegEnumValueW")
+	procRegDeleteValueW           = modadvapi32.NewProc("RegDeleteValueW")
+	procRegLoadMUIStringW         = modadvapi32.NewProc("RegLoadMUIStringW")
+	procRegConnectRegistryW       = modadvapi32.NewProc("RegConnectRegistryW")
+	procExpandEnvironmentStringsW = modkernel32.NewProc("ExpandEnvironmentStringsW")
+)
+
+func regCreateKeyEx(key syscall.Handle, subkey *uint16, reserved uint32, class *uint16, options uint32, desired uint32, sa *syscall.SecurityAttributes, result *syscall.Handle, disposition *uint32) (regerrno error) {
+	r0, _, _ := syscall.Syscall9(procRegCreateKeyExW.Addr(), 9, uintptr(key), uintptr(unsafe.Pointer(subkey)), uintptr(reserved), uintptr(unsafe.Pointer(class)), uintptr(options), uintptr(desired), uintptr(unsafe.Pointer(sa)), uintptr(unsafe.Pointer(result)), uintptr(unsafe.Pointer(disposition)))
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regDeleteKey(key syscall.Handle, subkey *uint16) (regerrno error) {
+	r0, _, _ := syscall.Syscall(procRegDeleteKeyW.Addr(), 2, uintptr(key), uintptr(unsafe.Pointer(subkey)), 0)
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regSetValueEx(key syscall.Handle, valueName *uint16, reserved uint32, vtype uint32, buf *byte, bufsize uint32) (regerrno error) {
+	r0, _, _ := syscall.Syscall6(procRegSetValueExW.Addr(), 6, uintptr(key), uintptr(unsafe.Pointer(valueName)), uintptr(reserved), uintptr(vtype), uintptr(unsafe.Pointer(buf)), uintptr(bufsize))
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regEnumValue(key syscall.Handle, index uint32, name *uint16, nameLen *uint32, reserved *uint32, valtype *uint32, buf *byte, buflen *uint32) (regerrno error) {
+	r0, _, _ := syscall.Syscall9(procRegEnumValueW.Addr(), 8, uintptr(key), uintptr(index), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(nameLen)), uintptr(unsafe.Pointer(reserved)), uintptr(unsafe.Pointer(valtype)), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(buflen)), 0)
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regDeleteValue(key syscall.Handle, name *uint16) (regerrno error) {
+	r0, _, _ := syscall.Syscall(procRegDeleteValueW.Addr(), 2, uintptr(key), uintptr(unsafe.Pointer(name)), 0)
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regLoadMUIString(key syscall.Handle, name *uint16, buf *uint16, buflen uint32, buflenCopied *uint32, flags uint32, dir *uint16) (regerrno error) {
+	r0, _, _ := syscall.Syscall9(procRegLoadMUIStringW.Addr(), 7, uintptr(key), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(buf)), uintptr(buflen), uintptr(unsafe.Pointer(buflenCopied)), uintptr(flags), uintptr(unsafe.Pointer(dir)), 0, 0)
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func regConnectRegistry(machinename *uint16, key syscall.Handle, result *syscall.Handle) (regerrno error) {
+	r0, _, _ := syscall.Syscall(procRegConnectRegistryW.Addr(), 3, uintptr(unsafe.Pointer(machinename)), uintptr(key), uintptr(unsafe.Pointer(result)))
+	if r0 != 0 {
+		regerrno = syscall.Errno(r0)
+	}
+	return
+}
+
+func expandEnvironmentStrings(src *uint16, dst *uint16, size uint32) (n uint32, err error) {
+	r0, _, e1 := syscall.Syscall(procExpandEnvironmentStringsW.Addr(), 3, uintptr(unsafe.Pointer(src)), uintptr(unsafe.Pointer(dst)), uintptr(size))
+	n = uint32(r0)
+	if n == 0 {
+		if e1 != 0 {
+			err = errnoErr(e1)
+		} else {
+			err = syscall.EINVAL
+		}
+	}
+	return
+}

vendor/golang.org/x/sys/windows/security_windows.go

@@ -0,0 +1,435 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+const (
+	STANDARD_RIGHTS_REQUIRED = 0xf0000
+	STANDARD_RIGHTS_READ     = 0x20000
+	STANDARD_RIGHTS_WRITE    = 0x20000
+	STANDARD_RIGHTS_EXECUTE  = 0x20000
+	STANDARD_RIGHTS_ALL      = 0x1F0000
+)
+
+const (
+	NameUnknown          = 0
+	NameFullyQualifiedDN = 1
+	NameSamCompatible    = 2
+	NameDisplay          = 3
+	NameUniqueId         = 6
+	NameCanonical        = 7
+	NameUserPrincipal    = 8
+	NameCanonicalEx      = 9
+	NameServicePrincipal = 10
+	NameDnsDomain        = 12
+)
+
+// This function returns 1 byte BOOLEAN rather than the 4 byte BOOL.
+// http://blogs.msdn.com/b/drnick/archive/2007/12/19/windows-and-upn-format-credentials.aspx
+//sys	TranslateName(accName *uint16, accNameFormat uint32, desiredNameFormat uint32, translatedName *uint16, nSize *uint32) (err error) [failretval&0xff==0] = secur32.TranslateNameW
+//sys	GetUserNameEx(nameFormat uint32, nameBuffre *uint16, nSize *uint32) (err error) [failretval&0xff==0] = secur32.GetUserNameExW
+
+// TranslateAccountName converts a directory service
+// object name from one format to another.
+func TranslateAccountName(username string, from, to uint32, initSize int) (string, error) {
+	u, e := UTF16PtrFromString(username)
+	if e != nil {
+		return "", e
+	}
+	n := uint32(50)
+	for {
+		b := make([]uint16, n)
+		e = TranslateName(u, from, to, &b[0], &n)
+		if e == nil {
+			return UTF16ToString(b[:n]), nil
+		}
+		if e != ERROR_INSUFFICIENT_BUFFER {
+			return "", e
+		}
+		if n <= uint32(len(b)) {
+			return "", e
+		}
+	}
+}
+
+const (
+	// do not reorder
+	NetSetupUnknownStatus = iota
+	NetSetupUnjoined
+	NetSetupWorkgroupName
+	NetSetupDomainName
+)
+
+type UserInfo10 struct {
+	Name       *uint16
+	Comment    *uint16
+	UsrComment *uint16
+	FullName   *uint16
+}
+
+//sys	NetUserGetInfo(serverName *uint16, userName *uint16, level uint32, buf **byte) (neterr error) = netapi32.NetUserGetInfo
+//sys	NetGetJoinInformation(server *uint16, name **uint16, bufType *uint32) (neterr error) = netapi32.NetGetJoinInformation
+//sys	NetApiBufferFree(buf *byte) (neterr error) = netapi32.NetApiBufferFree
+
+const (
+	// do not reorder
+	SidTypeUser = 1 + iota
+	SidTypeGroup
+	SidTypeDomain
+	SidTypeAlias
+	SidTypeWellKnownGroup
+	SidTypeDeletedAccount
+	SidTypeInvalid
+	SidTypeUnknown
+	SidTypeComputer
+	SidTypeLabel
+)
+
+type SidIdentifierAuthority struct {
+	Value [6]byte
+}
+
+var (
+	SECURITY_NULL_SID_AUTHORITY        = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 0}}
+	SECURITY_WORLD_SID_AUTHORITY       = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 1}}
+	SECURITY_LOCAL_SID_AUTHORITY       = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 2}}
+	SECURITY_CREATOR_SID_AUTHORITY     = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 3}}
+	SECURITY_NON_UNIQUE_AUTHORITY      = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 4}}
+	SECURITY_NT_AUTHORITY              = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 5}}
+	SECURITY_MANDATORY_LABEL_AUTHORITY = SidIdentifierAuthority{[6]byte{0, 0, 0, 0, 0, 16}}
+)
+
+const (
+	SECURITY_NULL_RID                   = 0
+	SECURITY_WORLD_RID                  = 0
+	SECURITY_LOCAL_RID                  = 0
+	SECURITY_CREATOR_OWNER_RID          = 0
+	SECURITY_CREATOR_GROUP_RID          = 1
+	SECURITY_DIALUP_RID                 = 1
+	SECURITY_NETWORK_RID                = 2
+	SECURITY_BATCH_RID                  = 3
+	SECURITY_INTERACTIVE_RID            = 4
+	SECURITY_LOGON_IDS_RID              = 5
+	SECURITY_SERVICE_RID                = 6
+	SECURITY_LOCAL_SYSTEM_RID           = 18
+	SECURITY_BUILTIN_DOMAIN_RID         = 32
+	SECURITY_PRINCIPAL_SELF_RID         = 10
+	SECURITY_CREATOR_OWNER_SERVER_RID   = 0x2
+	SECURITY_CREATOR_GROUP_SERVER_RID   = 0x3
+	SECURITY_LOGON_IDS_RID_COUNT        = 0x3
+	SECURITY_ANONYMOUS_LOGON_RID        = 0x7
+	SECURITY_PROXY_RID                  = 0x8
+	SECURITY_ENTERPRISE_CONTROLLERS_RID = 0x9
+	SECURITY_SERVER_LOGON_RID           = SECURITY_ENTERPRISE_CONTROLLERS_RID
+	SECURITY_AUTHENTICATED_USER_RID     = 0xb
+	SECURITY_RESTRICTED_CODE_RID        = 0xc
+	SECURITY_NT_NON_UNIQUE_RID          = 0x15
+)
+
+//sys	LookupAccountSid(systemName *uint16, sid *SID, name *uint16, nameLen *uint32, refdDomainName *uint16, refdDomainNameLen *uint32, use *uint32) (err error) = advapi32.LookupAccountSidW
+//sys	LookupAccountName(systemName *uint16, accountName *uint16, sid *SID, sidLen *uint32, refdDomainName *uint16, refdDomainNameLen *uint32, use *uint32) (err error) = advapi32.LookupAccountNameW
+//sys	ConvertSidToStringSid(sid *SID, stringSid **uint16) (err error) = advapi32.ConvertSidToStringSidW
+//sys	ConvertStringSidToSid(stringSid *uint16, sid **SID) (err error) = advapi32.ConvertStringSidToSidW
+//sys	GetLengthSid(sid *SID) (len uint32) = advapi32.GetLengthSid
+//sys	CopySid(destSidLen uint32, destSid *SID, srcSid *SID) (err error) = advapi32.CopySid
+//sys	AllocateAndInitializeSid(identAuth *SidIdentifierAuthority, subAuth byte, subAuth0 uint32, subAuth1 uint32, subAuth2 uint32, subAuth3 uint32, subAuth4 uint32, subAuth5 uint32, subAuth6 uint32, subAuth7 uint32, sid **SID) (err error) = advapi32.AllocateAndInitializeSid
+//sys	FreeSid(sid *SID) (err error) [failretval!=0] = advapi32.FreeSid
+//sys	EqualSid(sid1 *SID, sid2 *SID) (isEqual bool) = advapi32.EqualSid
+
+// The security identifier (SID) structure is a variable-length
+// structure used to uniquely identify users or groups.
+type SID struct{}
+
+// StringToSid converts a string-format security identifier
+// sid into a valid, functional sid.
+func StringToSid(s string) (*SID, error) {
+	var sid *SID
+	p, e := UTF16PtrFromString(s)
+	if e != nil {
+		return nil, e
+	}
+	e = ConvertStringSidToSid(p, &sid)
+	if e != nil {
+		return nil, e
+	}
+	defer LocalFree((Handle)(unsafe.Pointer(sid)))
+	return sid.Copy()
+}
+
+// LookupSID retrieves a security identifier sid for the account
+// and the name of the domain on which the account was found.
+// System specify target computer to search.
+func LookupSID(system, account string) (sid *SID, domain string, accType uint32, err error) {
+	if len(account) == 0 {
+		return nil, "", 0, syscall.EINVAL
+	}
+	acc, e := UTF16PtrFromString(account)
+	if e != nil {
+		return nil, "", 0, e
+	}
+	var sys *uint16
+	if len(system) > 0 {
+		sys, e = UTF16PtrFromString(system)
+		if e != nil {
+			return nil, "", 0, e
+		}
+	}
+	n := uint32(50)
+	dn := uint32(50)
+	for {
+		b := make([]byte, n)
+		db := make([]uint16, dn)
+		sid = (*SID)(unsafe.Pointer(&b[0]))
+		e = LookupAccountName(sys, acc, sid, &n, &db[0], &dn, &accType)
+		if e == nil {
+			return sid, UTF16ToString(db), accType, nil
+		}
+		if e != ERROR_INSUFFICIENT_BUFFER {
+			return nil, "", 0, e
+		}
+		if n <= uint32(len(b)) {
+			return nil, "", 0, e
+		}
+	}
+}
+
+// String converts sid to a string format
+// suitable for display, storage, or transmission.
+func (sid *SID) String() (string, error) {
+	var s *uint16
+	e := ConvertSidToStringSid(sid, &s)
+	if e != nil {
+		return "", e
+	}
+	defer LocalFree((Handle)(unsafe.Pointer(s)))
+	return UTF16ToString((*[256]uint16)(unsafe.Pointer(s))[:]), nil
+}
+
+// Len returns the length, in bytes, of a valid security identifier sid.
+func (sid *SID) Len() int {
+	return int(GetLengthSid(sid))
+}
+
+// Copy creates a duplicate of security identifier sid.
+func (sid *SID) Copy() (*SID, error) {
+	b := make([]byte, sid.Len())
+	sid2 := (*SID)(unsafe.Pointer(&b[0]))
+	e := CopySid(uint32(len(b)), sid2, sid)
+	if e != nil {
+		return nil, e
+	}
+	return sid2, nil
+}
+
+// LookupAccount retrieves the name of the account for this sid
+// and the name of the first domain on which this sid is found.
+// System specify target computer to search for.
+func (sid *SID) LookupAccount(system string) (account, domain string, accType uint32, err error) {
+	var sys *uint16
+	if len(system) > 0 {
+		sys, err = UTF16PtrFromString(system)
+		if err != nil {
+			return "", "", 0, err
+		}
+	}
+	n := uint32(50)
+	dn := uint32(50)
+	for {
+		b := make([]uint16, n)
+		db := make([]uint16, dn)
+		e := LookupAccountSid(sys, sid, &b[0], &n, &db[0], &dn, &accType)
+		if e == nil {
+			return UTF16ToString(b), UTF16ToString(db), accType, nil
+		}
+		if e != ERROR_INSUFFICIENT_BUFFER {
+			return "", "", 0, e
+		}
+		if n <= uint32(len(b)) {
+			return "", "", 0, e
+		}
+	}
+}
+
+const (
+	// do not reorder
+	TOKEN_ASSIGN_PRIMARY = 1 << iota
+	TOKEN_DUPLICATE
+	TOKEN_IMPERSONATE
+	TOKEN_QUERY
+	TOKEN_QUERY_SOURCE
+	TOKEN_ADJUST_PRIVILEGES
+	TOKEN_ADJUST_GROUPS
+	TOKEN_ADJUST_DEFAULT
+
+	TOKEN_ALL_ACCESS = STANDARD_RIGHTS_REQUIRED |
+		TOKEN_ASSIGN_PRIMARY |
+		TOKEN_DUPLICATE |
+		TOKEN_IMPERSONATE |
+		TOKEN_QUERY |
+		TOKEN_QUERY_SOURCE |
+		TOKEN_ADJUST_PRIVILEGES |
+		TOKEN_ADJUST_GROUPS |
+		TOKEN_ADJUST_DEFAULT
+	TOKEN_READ  = STANDARD_RIGHTS_READ | TOKEN_QUERY
+	TOKEN_WRITE = STANDARD_RIGHTS_WRITE |
+		TOKEN_ADJUST_PRIVILEGES |
+		TOKEN_ADJUST_GROUPS |
+		TOKEN_ADJUST_DEFAULT
+	TOKEN_EXECUTE = STANDARD_RIGHTS_EXECUTE
+)
+
+const (
+	// do not reorder
+	TokenUser = 1 + iota
+	TokenGroups
+	TokenPrivileges
+	TokenOwner
+	TokenPrimaryGroup
+	TokenDefaultDacl
+	TokenSource
+	TokenType
+	TokenImpersonationLevel
+	TokenStatistics
+	TokenRestrictedSids
+	TokenSessionId
+	TokenGroupsAndPrivileges
+	TokenSessionReference
+	TokenSandBoxInert
+	TokenAuditPolicy
+	TokenOrigin
+	TokenElevationType
+	TokenLinkedToken
+	TokenElevation
+	TokenHasRestrictions
+	TokenAccessInformation
+	TokenVirtualizationAllowed
+	TokenVirtualizationEnabled
+	TokenIntegrityLevel
+	TokenUIAccess
+	TokenMandatoryPolicy
+	TokenLogonSid
+	MaxTokenInfoClass
+)
+
+type SIDAndAttributes struct {
+	Sid        *SID
+	Attributes uint32
+}
+
+type Tokenuser struct {
+	User SIDAndAttributes
+}
+
+type Tokenprimarygroup struct {
+	PrimaryGroup *SID
+}
+
+type Tokengroups struct {
+	GroupCount uint32
+	Groups     [1]SIDAndAttributes
+}
+
+//sys	OpenProcessToken(h Handle, access uint32, token *Token) (err error) = advapi32.OpenProcessToken
+//sys	GetTokenInformation(t Token, infoClass uint32, info *byte, infoLen uint32, returnedLen *uint32) (err error) = advapi32.GetTokenInformation
+//sys	GetUserProfileDirectory(t Token, dir *uint16, dirLen *uint32) (err error) = userenv.GetUserProfileDirectoryW
+
+// An access token contains the security information for a logon session.
+// The system creates an access token when a user logs on, and every
+// process executed on behalf of the user has a copy of the token.
+// The token identifies the user, the user's groups, and the user's
+// privileges. The system uses the token to control access to securable
+// objects and to control the ability of the user to perform various
+// system-related operations on the local computer.
+type Token Handle
+
+// OpenCurrentProcessToken opens the access token
+// associated with current process.
+func OpenCurrentProcessToken() (Token, error) {
+	p, e := GetCurrentProcess()
+	if e != nil {
+		return 0, e
+	}
+	var t Token
+	e = OpenProcessToken(p, TOKEN_QUERY, &t)
+	if e != nil {
+		return 0, e
+	}
+	return t, nil
+}
+
+// Close releases access to access token.
+func (t Token) Close() error {
+	return CloseHandle(Handle(t))
+}
+
+// getInfo retrieves a specified type of information about an access token.
+func (t Token) getInfo(class uint32, initSize int) (unsafe.Pointer, error) {
+	n := uint32(initSize)
+	for {
+		b := make([]byte, n)
+		e := GetTokenInformation(t, class, &b[0], uint32(len(b)), &n)
+		if e == nil {
+			return unsafe.Pointer(&b[0]), nil
+		}
+		if e != ERROR_INSUFFICIENT_BUFFER {
+			return nil, e
+		}
+		if n <= uint32(len(b)) {
+			return nil, e
+		}
+	}
+}
+
+// GetTokenUser retrieves access token t user account information.
+func (t Token) GetTokenUser() (*Tokenuser, error) {
+	i, e := t.getInfo(TokenUser, 50)
+	if e != nil {
+		return nil, e
+	}
+	return (*Tokenuser)(i), nil
+}
+
+// GetTokenGroups retrieves group accounts associated with access token t.
+func (t Token) GetTokenGroups() (*Tokengroups, error) {
+	i, e := t.getInfo(TokenGroups, 50)
+	if e != nil {
+		return nil, e
+	}
+	return (*Tokengroups)(i), nil
+}
+
+// GetTokenPrimaryGroup retrieves access token t primary group information.
+// A pointer to a SID structure representing a group that will become
+// the primary group of any objects created by a process using this access token.
+func (t Token) GetTokenPrimaryGroup() (*Tokenprimarygroup, error) {
+	i, e := t.getInfo(TokenPrimaryGroup, 50)
+	if e != nil {
+		return nil, e
+	}
+	return (*Tokenprimarygroup)(i), nil
+}
+
+// GetUserProfileDirectory retrieves path to the
+// root directory of the access token t user's profile.
+func (t Token) GetUserProfileDirectory() (string, error) {
+	n := uint32(100)
+	for {
+		b := make([]uint16, n)
+		e := GetUserProfileDirectory(t, &b[0], &n)
+		if e == nil {
+			return UTF16ToString(b), nil
+		}
+		if e != ERROR_INSUFFICIENT_BUFFER {
+			return "", e
+		}
+		if n <= uint32(len(b)) {
+			return "", e
+		}
+	}
+}

vendor/golang.org/x/sys/windows/service.go

@@ -0,0 +1,164 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package windows
+
+const (
+	SC_MANAGER_CONNECT            = 1
+	SC_MANAGER_CREATE_SERVICE     = 2
+	SC_MANAGER_ENUMERATE_SERVICE  = 4
+	SC_MANAGER_LOCK               = 8
+	SC_MANAGER_QUERY_LOCK_STATUS  = 16
+	SC_MANAGER_MODIFY_BOOT_CONFIG = 32
+	SC_MANAGER_ALL_ACCESS         = 0xf003f
+)
+
+//sys	OpenSCManager(machineName *uint16, databaseName *uint16, access uint32) (handle Handle, err error) [failretval==0] = advapi32.OpenSCManagerW
+
+const (
+	SERVICE_KERNEL_DRIVER       = 1
+	SERVICE_FILE_SYSTEM_DRIVER  = 2
+	SERVICE_ADAPTER             = 4
+	SERVICE_RECOGNIZER_DRIVER   = 8
+	SERVICE_WIN32_OWN_PROCESS   = 16
+	SERVICE_WIN32_SHARE_PROCESS = 32
+	SERVICE_WIN32               = SERVICE_WIN32_OWN_PROCESS | SERVICE_WIN32_SHARE_PROCESS
+	SERVICE_INTERACTIVE_PROCESS = 256
+	SERVICE_DRIVER              = SERVICE_KERNEL_DRIVER | SERVICE_FILE_SYSTEM_DRIVER | SERVICE_RECOGNIZER_DRIVER
+	SERVICE_TYPE_ALL            = SERVICE_WIN32 | SERVICE_ADAPTER | SERVICE_DRIVER | SERVICE_INTERACTIVE_PROCESS
+
+	SERVICE_BOOT_START   = 0
+	SERVICE_SYSTEM_START = 1
+	SERVICE_AUTO_START   = 2
+	SERVICE_DEMAND_START = 3
+	SERVICE_DISABLED     = 4
+
+	SERVICE_ERROR_IGNORE   = 0
+	SERVICE_ERROR_NORMAL   = 1
+	SERVICE_ERROR_SEVERE   = 2
+	SERVICE_ERROR_CRITICAL = 3
+
+	SC_STATUS_PROCESS_INFO = 0
+
+	SERVICE_STOPPED          = 1
+	SERVICE_START_PENDING    = 2
+	SERVICE_STOP_PENDING     = 3
+	SERVICE_RUNNING          = 4
+	SERVICE_CONTINUE_PENDING = 5
+	SERVICE_PAUSE_PENDING    = 6
+	SERVICE_PAUSED           = 7
+	SERVICE_NO_CHANGE        = 0xffffffff
+
+	SERVICE_ACCEPT_STOP                  = 1
+	SERVICE_ACCEPT_PAUSE_CONTINUE        = 2
+	SERVICE_ACCEPT_SHUTDOWN              = 4
+	SERVICE_ACCEPT_PARAMCHANGE           = 8
+	SERVICE_ACCEPT_NETBINDCHANGE         = 16
+	SERVICE_ACCEPT_HARDWAREPROFILECHANGE = 32
+	SERVICE_ACCEPT_POWEREVENT            = 64
+	SERVICE_ACCEPT_SESSIONCHANGE         = 128
+
+	SERVICE_CONTROL_STOP                  = 1
+	SERVICE_CONTROL_PAUSE                 = 2
+	SERVICE_CONTROL_CONTINUE              = 3
+	SERVICE_CONTROL_INTERROGATE           = 4
+	SERVICE_CONTROL_SHUTDOWN              = 5
+	SERVICE_CONTROL_PARAMCHANGE           = 6
+	SERVICE_CONTROL_NETBINDADD            = 7
+	SERVICE_CONTROL_NETBINDREMOVE         = 8
+	SERVICE_CONTROL_NETBINDENABLE         = 9
+	SERVICE_CONTROL_NETBINDDISABLE        = 10
+	SERVICE_CONTROL_DEVICEEVENT           = 11
+	SERVICE_CONTROL_HARDWAREPROFILECHANGE = 12
+	SERVICE_CONTROL_POWEREVENT            = 13
+	SERVICE_CONTROL_SESSIONCHANGE         = 14
+
+	SERVICE_ACTIVE    = 1
+	SERVICE_INACTIVE  = 2
+	SERVICE_STATE_ALL = 3
+
+	SERVICE_QUERY_CONFIG           = 1
+	SERVICE_CHANGE_CONFIG          = 2
+	SERVICE_QUERY_STATUS           = 4
+	SERVICE_ENUMERATE_DEPENDENTS   = 8
+	SERVICE_START                  = 16
+	SERVICE_STOP                   = 32
+	SERVICE_PAUSE_CONTINUE         = 64
+	SERVICE_INTERROGATE            = 128
+	SERVICE_USER_DEFINED_CONTROL   = 256
+	SERVICE_ALL_ACCESS             = STANDARD_RIGHTS_REQUIRED | SERVICE_QUERY_CONFIG | SERVICE_CHANGE_CONFIG | SERVICE_QUERY_STATUS | SERVICE_ENUMERATE_DEPENDENTS | SERVICE_START | SERVICE_STOP | SERVICE_PAUSE_CONTINUE | SERVICE_INTERROGATE | SERVICE_USER_DEFINED_CONTROL
+	SERVICE_RUNS_IN_SYSTEM_PROCESS = 1
+	SERVICE_CONFIG_DESCRIPTION     = 1
+	SERVICE_CONFIG_FAILURE_ACTIONS = 2
+
+	NO_ERROR = 0
+
+	SC_ENUM_PROCESS_INFO = 0
+)
+
+type SERVICE_STATUS struct {
+	ServiceType             uint32
+	CurrentState            uint32
+	ControlsAccepted        uint32
+	Win32ExitCode           uint32
+	ServiceSpecificExitCode uint32
+	CheckPoint              uint32
+	WaitHint                uint32
+}
+
+type SERVICE_TABLE_ENTRY struct {
+	ServiceName *uint16
+	ServiceProc uintptr
+}
+
+type QUERY_SERVICE_CONFIG struct {
+	ServiceType      uint32
+	StartType        uint32
+	ErrorControl     uint32
+	BinaryPathName   *uint16
+	LoadOrderGroup   *uint16
+	TagId            uint32
+	Dependencies     *uint16
+	ServiceStartName *uint16
+	DisplayName      *uint16
+}
+
+type SERVICE_DESCRIPTION struct {
+	Description *uint16
+}
+
+type SERVICE_STATUS_PROCESS struct {
+	ServiceType             uint32
+	CurrentState            uint32
+	ControlsAccepted        uint32
+	Win32ExitCode           uint32
+	ServiceSpecificExitCode uint32
+	CheckPoint              uint32
+	WaitHint                uint32
+	ProcessId               uint32
+	ServiceFlags            uint32
+}
+
+type ENUM_SERVICE_STATUS_PROCESS struct {
+	ServiceName          *uint16
+	DisplayName          *uint16
+	ServiceStatusProcess SERVICE_STATUS_PROCESS
+}
+
+//sys	CloseServiceHandle(handle Handle) (err error) = advapi32.CloseServiceHandle
+//sys	CreateService(mgr Handle, serviceName *uint16, displayName *uint16, access uint32, srvType uint32, startType uint32, errCtl uint32, pathName *uint16, loadOrderGroup *uint16, tagId *uint32, dependencies *uint16, serviceStartName *uint16, password *uint16) (handle Handle, err error) [failretval==0] = advapi32.CreateServiceW
+//sys	OpenService(mgr Handle, serviceName *uint16, access uint32) (handle Handle, err error) [failretval==0] = advapi32.OpenServiceW
+//sys	DeleteService(service Handle) (err error) = advapi32.DeleteService
+//sys	StartService(service Handle, numArgs uint32, argVectors **uint16) (err error) = advapi32.StartServiceW
+//sys	QueryServiceStatus(service Handle, status *SERVICE_STATUS) (err error) = advapi32.QueryServiceStatus
+//sys	ControlService(service Handle, control uint32, status *SERVICE_STATUS) (err error) = advapi32.ControlService
+//sys	StartServiceCtrlDispatcher(serviceTable *SERVICE_TABLE_ENTRY) (err error) = advapi32.StartServiceCtrlDispatcherW
+//sys	SetServiceStatus(service Handle, serviceStatus *SERVICE_STATUS) (err error) = advapi32.SetServiceStatus
+//sys	ChangeServiceConfig(service Handle, serviceType uint32, startType uint32, errorControl uint32, binaryPathName *uint16, loadOrderGroup *uint16, tagId *uint32, dependencies *uint16, serviceStartName *uint16, password *uint16, displayName *uint16) (err error) = advapi32.ChangeServiceConfigW
+//sys	QueryServiceConfig(service Handle, serviceConfig *QUERY_SERVICE_CONFIG, bufSize uint32, bytesNeeded *uint32) (err error) = advapi32.QueryServiceConfigW
+//sys	ChangeServiceConfig2(service Handle, infoLevel uint32, info *byte) (err error) = advapi32.ChangeServiceConfig2W
+//sys	QueryServiceConfig2(service Handle, infoLevel uint32, buff *byte, buffSize uint32, bytesNeeded *uint32) (err error) = advapi32.QueryServiceConfig2W
+//sys	EnumServicesStatusEx(mgr Handle, infoLevel uint32, serviceType uint32, serviceState uint32, services *byte, bufSize uint32, bytesNeeded *uint32, servicesReturned *uint32, resumeHandle *uint32, groupName *uint16) (err error) = advapi32.EnumServicesStatusExW

vendor/golang.org/x/sys/windows/str.go

@@ -0,0 +1,22 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package windows
+
+func itoa(val int) string { // do it here rather than with fmt to avoid dependency
+	if val < 0 {
+		return "-" + itoa(-val)
+	}
+	var buf [32]byte // big enough for int64
+	i := len(buf) - 1
+	for val >= 10 {
+		buf[i] = byte(val%10 + '0')
+		i--
+		val /= 10
+	}
+	buf[i] = byte(val + '0')
+	return string(buf[i:])
+}

vendor/golang.org/x/sys/windows/svc/eventlog/install.go

@@ -0,0 +1,80 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package eventlog
+
+import (
+	"errors"
+
+	"golang.org/x/sys/windows"
+	"golang.org/x/sys/windows/registry"
+)
+
+const (
+	// Log levels.
+	Info    = windows.EVENTLOG_INFORMATION_TYPE
+	Warning = windows.EVENTLOG_WARNING_TYPE
+	Error   = windows.EVENTLOG_ERROR_TYPE
+)
+
+const addKeyName = `SYSTEM\CurrentControlSet\Services\EventLog\Application`
+
+// Install modifies PC registry to allow logging with an event source src.
+// It adds all required keys and values to the event log registry key.
+// Install uses msgFile as the event message file. If useExpandKey is true,
+// the event message file is installed as REG_EXPAND_SZ value,
+// otherwise as REG_SZ. Use bitwise of log.Error, log.Warning and
+// log.Info to specify events supported by the new event source.
+func Install(src, msgFile string, useExpandKey bool, eventsSupported uint32) error {
+	appkey, err := registry.OpenKey(registry.LOCAL_MACHINE, addKeyName, registry.CREATE_SUB_KEY)
+	if err != nil {
+		return err
+	}
+	defer appkey.Close()
+
+	sk, alreadyExist, err := registry.CreateKey(appkey, src, registry.SET_VALUE)
+	if err != nil {
+		return err
+	}
+	defer sk.Close()
+	if alreadyExist {
+		return errors.New(addKeyName + `\` + src + " registry key already exists")
+	}
+
+	err = sk.SetDWordValue("CustomSource", 1)
+	if err != nil {
+		return err
+	}
+	if useExpandKey {
+		err = sk.SetExpandStringValue("EventMessageFile", msgFile)
+	} else {
+		err = sk.SetStringValue("EventMessageFile", msgFile)
+	}
+	if err != nil {
+		return err
+	}
+	err = sk.SetDWordValue("TypesSupported", eventsSupported)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+// InstallAsEventCreate is the same as Install, but uses
+// %SystemRoot%\System32\EventCreate.exe as the event message file.
+func InstallAsEventCreate(src string, eventsSupported uint32) error {
+	return Install(src, "%SystemRoot%\\System32\\EventCreate.exe", true, eventsSupported)
+}
+
+// Remove deletes all registry elements installed by the correspondent Install.
+func Remove(src string) error {
+	appkey, err := registry.OpenKey(registry.LOCAL_MACHINE, addKeyName, registry.SET_VALUE)
+	if err != nil {
+		return err
+	}
+	defer appkey.Close()
+	return registry.DeleteKey(appkey, src)
+}

vendor/golang.org/x/sys/windows/svc/eventlog/log.go

@@ -0,0 +1,70 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+// Package eventlog implements access to Windows event log.
+//
+package eventlog
+
+import (
+	"errors"
+	"syscall"
+
+	"golang.org/x/sys/windows"
+)
+
+// Log provides access to the system log.
+type Log struct {
+	Handle windows.Handle
+}
+
+// Open retrieves a handle to the specified event log.
+func Open(source string) (*Log, error) {
+	return OpenRemote("", source)
+}
+
+// OpenRemote does the same as Open, but on different computer host.
+func OpenRemote(host, source string) (*Log, error) {
+	if source == "" {
+		return nil, errors.New("Specify event log source")
+	}
+	var s *uint16
+	if host != "" {
+		s = syscall.StringToUTF16Ptr(host)
+	}
+	h, err := windows.RegisterEventSource(s, syscall.StringToUTF16Ptr(source))
+	if err != nil {
+		return nil, err
+	}
+	return &Log{Handle: h}, nil
+}
+
+// Close closes event log l.
+func (l *Log) Close() error {
+	return windows.DeregisterEventSource(l.Handle)
+}
+
+func (l *Log) report(etype uint16, eid uint32, msg string) error {
+	ss := []*uint16{syscall.StringToUTF16Ptr(msg)}
+	return windows.ReportEvent(l.Handle, etype, 0, eid, 0, 1, 0, &ss[0], nil)
+}
+
+// Info writes an information event msg with event id eid to the end of event log l.
+// When EventCreate.exe is used, eid must be between 1 and 1000.
+func (l *Log) Info(eid uint32, msg string) error {
+	return l.report(windows.EVENTLOG_INFORMATION_TYPE, eid, msg)
+}
+
+// Warning writes an warning event msg with event id eid to the end of event log l.
+// When EventCreate.exe is used, eid must be between 1 and 1000.
+func (l *Log) Warning(eid uint32, msg string) error {
+	return l.report(windows.EVENTLOG_WARNING_TYPE, eid, msg)
+}
+
+// Error writes an error event msg with event id eid to the end of event log l.
+// When EventCreate.exe is used, eid must be between 1 and 1000.
+func (l *Log) Error(eid uint32, msg string) error {
+	return l.report(windows.EVENTLOG_ERROR_TYPE, eid, msg)
+}

vendor/golang.org/x/sys/windows/syscall.go

@@ -0,0 +1,71 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+// Package windows contains an interface to the low-level operating system
+// primitives.  OS details vary depending on the underlying system, and
+// by default, godoc will display the OS-specific documentation for the current
+// system.  If you want godoc to display syscall documentation for another
+// system, set $GOOS and $GOARCH to the desired system.  For example, if
+// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
+// to freebsd and $GOARCH to arm.
+// The primary use of this package is inside other packages that provide a more
+// portable interface to the system, such as "os", "time" and "net".  Use
+// those packages rather than this one if you can.
+// For details of the functions and data types in this package consult
+// the manuals for the appropriate operating system.
+// These calls return err == nil to indicate success; otherwise
+// err represents an operating system error describing the failure and
+// holds a value of type syscall.Errno.
+package windows // import "golang.org/x/sys/windows"
+
+import (
+	"syscall"
+)
+
+// ByteSliceFromString returns a NUL-terminated slice of bytes
+// containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, syscall.EINVAL).
+func ByteSliceFromString(s string) ([]byte, error) {
+	for i := 0; i < len(s); i++ {
+		if s[i] == 0 {
+			return nil, syscall.EINVAL
+		}
+	}
+	a := make([]byte, len(s)+1)
+	copy(a, s)
+	return a, nil
+}
+
+// BytePtrFromString returns a pointer to a NUL-terminated array of
+// bytes containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, syscall.EINVAL).
+func BytePtrFromString(s string) (*byte, error) {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		return nil, err
+	}
+	return &a[0], nil
+}
+
+// Single-word zero for use when we need a valid pointer to 0 bytes.
+// See mksyscall.pl.
+var _zero uintptr
+
+func (ts *Timespec) Unix() (sec int64, nsec int64) {
+	return int64(ts.Sec), int64(ts.Nsec)
+}
+
+func (tv *Timeval) Unix() (sec int64, nsec int64) {
+	return int64(tv.Sec), int64(tv.Usec) * 1000
+}
+
+func (ts *Timespec) Nano() int64 {
+	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
+}
+
+func (tv *Timeval) Nano() int64 {
+	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
+}

vendor/golang.org/x/sys/windows/types_windows_386.go

@@ -0,0 +1,22 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+type WSAData struct {
+	Version      uint16
+	HighVersion  uint16
+	Description  [WSADESCRIPTION_LEN + 1]byte
+	SystemStatus [WSASYS_STATUS_LEN + 1]byte
+	MaxSockets   uint16
+	MaxUdpDg     uint16
+	VendorInfo   *byte
+}
+
+type Servent struct {
+	Name    *byte
+	Aliases **byte
+	Port    uint16
+	Proto   *byte
+}

vendor/golang.org/x/sys/windows/types_windows_amd64.go

@@ -0,0 +1,22 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package windows
+
+type WSAData struct {
+	Version      uint16
+	HighVersion  uint16
+	MaxSockets   uint16
+	MaxUdpDg     uint16
+	VendorInfo   *byte
+	Description  [WSADESCRIPTION_LEN + 1]byte
+	SystemStatus [WSASYS_STATUS_LEN + 1]byte
+}
+
+type Servent struct {
+	Name    *byte
+	Aliases **byte
+	Proto   *byte
+	Port    uint16
+}

vendor/gopkg.in/alecthomas/kingpin.v2/COPYING

@@ -0,0 +1,19 @@
+Copyright (C) 2014 Alec Thomas
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

vendor/gopkg.in/alecthomas/kingpin.v2/README.md

@@ -0,0 +1,674 @@
+# Kingpin - A Go (golang) command line and flag parser
+[![](https://godoc.org/github.com/alecthomas/kingpin?status.svg)](http://godoc.org/github.com/alecthomas/kingpin) [![Build Status](https://travis-ci.org/alecthomas/kingpin.svg?branch=master)](https://travis-ci.org/alecthomas/kingpin) [![Gitter chat](https://badges.gitter.im/alecthomas.png)](https://gitter.im/alecthomas/Lobby)
+
+
+
+<!-- MarkdownTOC -->
+
+- [Overview](#overview)
+- [Features](#features)
+- [User-visible changes between v1 and v2](#user-visible-changes-between-v1-and-v2)
+  - [Flags can be used at any point after their definition.](#flags-can-be-used-at-any-point-after-their-definition)
+  - [Short flags can be combined with their parameters](#short-flags-can-be-combined-with-their-parameters)
+- [API changes between v1 and v2](#api-changes-between-v1-and-v2)
+- [Versions](#versions)
+  - [V2 is the current stable version](#v2-is-the-current-stable-version)
+  - [V1 is the OLD stable version](#v1-is-the-old-stable-version)
+- [Change History](#change-history)
+- [Examples](#examples)
+  - [Simple Example](#simple-example)
+  - [Complex Example](#complex-example)
+- [Reference Documentation](#reference-documentation)
+  - [Displaying errors and usage information](#displaying-errors-and-usage-information)
+  - [Sub-commands](#sub-commands)
+  - [Custom Parsers](#custom-parsers)
+  - [Repeatable flags](#repeatable-flags)
+  - [Boolean Values](#boolean-values)
+  - [Default Values](#default-values)
+  - [Place-holders in Help](#place-holders-in-help)
+  - [Consuming all remaining arguments](#consuming-all-remaining-arguments)
+  - [Bash/ZSH Shell Completion](#bashzsh-shell-completion)
+  - [Supporting -h for help](#supporting--h-for-help)
+  - [Custom help](#custom-help)
+
+<!-- /MarkdownTOC -->
+
+## Overview
+
+Kingpin is a [fluent-style](http://en.wikipedia.org/wiki/Fluent_interface),
+type-safe command-line parser. It supports flags, nested commands, and
+positional arguments.
+
+Install it with:
+
+    $ go get gopkg.in/alecthomas/kingpin.v2
+
+It looks like this:
+
+```go
+var (
+  verbose = kingpin.Flag("verbose", "Verbose mode.").Short('v').Bool()
+  name    = kingpin.Arg("name", "Name of user.").Required().String()
+)
+
+func main() {
+  kingpin.Parse()
+  fmt.Printf("%v, %s\n", *verbose, *name)
+}
+```
+
+More [examples](https://github.com/alecthomas/kingpin/tree/master/_examples) are available.
+
+Second to parsing, providing the user with useful help is probably the most
+important thing a command-line parser does. Kingpin tries to provide detailed
+contextual help if `--help` is encountered at any point in the command line
+(excluding after `--`).
+
+## Features
+
+- Help output that isn't as ugly as sin.
+- Fully [customisable help](#custom-help), via Go templates.
+- Parsed, type-safe flags (`kingpin.Flag("f", "help").Int()`)
+- Parsed, type-safe positional arguments (`kingpin.Arg("a", "help").Int()`).
+- Parsed, type-safe, arbitrarily deep commands (`kingpin.Command("c", "help")`).
+- Support for required flags and required positional arguments (`kingpin.Flag("f", "").Required().Int()`).
+- Support for arbitrarily nested default commands (`command.Default()`).
+- Callbacks per command, flag and argument (`kingpin.Command("c", "").Action(myAction)`).
+- POSIX-style short flag combining (`-a -b` -> `-ab`).
+- Short-flag+parameter combining (`-a parm` -> `-aparm`).
+- Read command-line from files (`@<file>`).
+- Automatically generate man pages (`--help-man`).
+
+## User-visible changes between v1 and v2
+
+### Flags can be used at any point after their definition.
+
+Flags can be specified at any point after their definition, not just
+*immediately after their associated command*. From the chat example below, the
+following used to be required:
+
+```
+$ chat --server=chat.server.com:8080 post --image=~/Downloads/owls.jpg pics
+```
+
+But the following will now work:
+
+```
+$ chat post --server=chat.server.com:8080 --image=~/Downloads/owls.jpg pics
+```
+
+### Short flags can be combined with their parameters
+
+Previously, if a short flag was used, any argument to that flag would have to
+be separated by a space. That is no longer the case.
+
+## API changes between v1 and v2
+
+- `ParseWithFileExpansion()` is gone. The new parser directly supports expanding `@<file>`.
+- Added `FatalUsage()` and `FatalUsageContext()` for displaying an error + usage and terminating.
+- `Dispatch()` renamed to `Action()`.
+- Added `ParseContext()` for parsing a command line into its intermediate context form without executing.
+- Added `Terminate()` function to override the termination function.
+- Added `UsageForContextWithTemplate()` for printing usage via a custom template.
+- Added `UsageTemplate()` for overriding the default template to use. Two templates are included:
+    1. `DefaultUsageTemplate` - default template.
+    2. `CompactUsageTemplate` - compact command template for larger applications.
+
+## Versions
+
+Kingpin uses [gopkg.in](https://gopkg.in/alecthomas/kingpin) for versioning.
+
+The current stable version is [gopkg.in/alecthomas/kingpin.v2](https://gopkg.in/alecthomas/kingpin.v2). The previous version, [gopkg.in/alecthomas/kingpin.v1](https://gopkg.in/alecthomas/kingpin.v1), is deprecated and in maintenance mode.
+
+### [V2](https://gopkg.in/alecthomas/kingpin.v2) is the current stable version
+
+Installation:
+
+```sh
+$ go get gopkg.in/alecthomas/kingpin.v2
+```
+
+### [V1](https://gopkg.in/alecthomas/kingpin.v1) is the OLD stable version
+
+Installation:
+
+```sh
+$ go get gopkg.in/alecthomas/kingpin.v1
+```
+
+## Change History
+
+- *2015-09-19* -- Stable v2.1.0 release.
+    - Added `command.Default()` to specify a default command to use if no other
+      command matches. This allows for convenient user shortcuts.
+    - Exposed `HelpFlag` and `VersionFlag` for further customisation.
+    - `Action()` and `PreAction()` added and both now support an arbitrary
+      number of callbacks.
+    - `kingpin.SeparateOptionalFlagsUsageTemplate`.
+    - `--help-long` and `--help-man` (hidden by default) flags.
+    - Flags are "interspersed" by default, but can be disabled with `app.Interspersed(false)`.
+    - Added flags for all simple builtin types (int8, uint16, etc.) and slice variants.
+    - Use `app.Writer(os.Writer)` to specify the default writer for all output functions.
+    - Dropped `os.Writer` prefix from all printf-like functions.
+
+- *2015-05-22* -- Stable v2.0.0 release.
+    - Initial stable release of v2.0.0.
+    - Fully supports interspersed flags, commands and arguments.
+    - Flags can be present at any point after their logical definition.
+    - Application.Parse() terminates if commands are present and a command is not parsed.
+    - Dispatch() -> Action().
+    - Actions are dispatched after all values are populated.
+    - Override termination function (defaults to os.Exit).
+    - Override output stream (defaults to os.Stderr).
+    - Templatised usage help, with default and compact templates.
+    - Make error/usage functions more consistent.
+    - Support argument expansion from files by default (with @<file>).
+    - Fully public data model is available via .Model().
+    - Parser has been completely refactored.
+    - Parsing and execution has been split into distinct stages.
+    - Use `go generate` to generate repeated flags.
+    - Support combined short-flag+argument: -fARG.
+
+- *2015-01-23* -- Stable v1.3.4 release.
+    - Support "--" for separating flags from positional arguments.
+    - Support loading flags from files (ParseWithFileExpansion()). Use @FILE as an argument.
+    - Add post-app and post-cmd validation hooks. This allows arbitrary validation to be added.
+    - A bunch of improvements to help usage and formatting.
+    - Support arbitrarily nested sub-commands.
+
+- *2014-07-08* -- Stable v1.2.0 release.
+    - Pass any value through to `Strings()` when final argument.
+      Allows for values that look like flags to be processed.
+    - Allow `--help` to be used with commands.
+    - Support `Hidden()` flags.
+    - Parser for [units.Base2Bytes](https://github.com/alecthomas/units)
+      type. Allows for flags like `--ram=512MB` or `--ram=1GB`.
+    - Add an `Enum()` value, allowing only one of a set of values
+      to be selected. eg. `Flag(...).Enum("debug", "info", "warning")`.
+
+- *2014-06-27* -- Stable v1.1.0 release.
+    - Bug fixes.
+    - Always return an error (rather than panicing) when misconfigured.
+    - `OpenFile(flag, perm)` value type added, for finer control over opening files.
+    - Significantly improved usage formatting.
+
+- *2014-06-19* -- Stable v1.0.0 release.
+    - Support [cumulative positional](#consuming-all-remaining-arguments) arguments.
+    - Return error rather than panic when there are fatal errors not caught by
+      the type system. eg. when a default value is invalid.
+    - Use gokpg.in.
+
+- *2014-06-10* -- Place-holder streamlining.
+    - Renamed `MetaVar` to `PlaceHolder`.
+    - Removed `MetaVarFromDefault`. Kingpin now uses [heuristics](#place-holders-in-help)
+      to determine what to display.
+
+## Examples
+
+### Simple Example
+
+Kingpin can be used for simple flag+arg applications like so:
+
+```
+$ ping --help
+usage: ping [<flags>] <ip> [<count>]
+
+Flags:
+  --debug            Enable debug mode.
+  --help             Show help.
+  -t, --timeout=5s   Timeout waiting for ping.
+
+Args:
+  <ip>        IP address to ping.
+  [<count>]   Number of packets to send
+$ ping 1.2.3.4 5
+Would ping: 1.2.3.4 with timeout 5s and count 0
+```
+
+From the following source:
+
+```go
+package main
+
+import (
+  "fmt"
+
+  "gopkg.in/alecthomas/kingpin.v2"
+)
+
+var (
+  debug   = kingpin.Flag("debug", "Enable debug mode.").Bool()
+  timeout = kingpin.Flag("timeout", "Timeout waiting for ping.").Default("5s").OverrideDefaultFromEnvar("PING_TIMEOUT").Short('t').Duration()
+  ip      = kingpin.Arg("ip", "IP address to ping.").Required().IP()
+  count   = kingpin.Arg("count", "Number of packets to send").Int()
+)
+
+func main() {
+  kingpin.Version("0.0.1")
+  kingpin.Parse()
+  fmt.Printf("Would ping: %s with timeout %s and count %d\n", *ip, *timeout, *count)
+}
+```
+
+### Complex Example
+
+Kingpin can also produce complex command-line applications with global flags,
+subcommands, and per-subcommand flags, like this:
+
+```
+$ chat --help
+usage: chat [<flags>] <command> [<flags>] [<args> ...]
+
+A command-line chat application.
+
+Flags:
+  --help              Show help.
+  --debug             Enable debug mode.
+  --server=127.0.0.1  Server address.
+
+Commands:
+  help [<command>]
+    Show help for a command.
+
+  register <nick> <name>
+    Register a new user.
+
+  post [<flags>] <channel> [<text>]
+    Post a message to a channel.
+
+$ chat help post
+usage: chat [<flags>] post [<flags>] <channel> [<text>]
+
+Post a message to a channel.
+
+Flags:
+  --image=IMAGE  Image to post.
+
+Args:
+  <channel>  Channel to post to.
+  [<text>]   Text to post.
+
+$ chat post --image=~/Downloads/owls.jpg pics
+...
+```
+
+From this code:
+
+```go
+package main
+
+import (
+  "os"
+  "strings"
+  "gopkg.in/alecthomas/kingpin.v2"
+)
+
+var (
+  app      = kingpin.New("chat", "A command-line chat application.")
+  debug    = app.Flag("debug", "Enable debug mode.").Bool()
+  serverIP = app.Flag("server", "Server address.").Default("127.0.0.1").IP()
+
+  register     = app.Command("register", "Register a new user.")
+  registerNick = register.Arg("nick", "Nickname for user.").Required().String()
+  registerName = register.Arg("name", "Name of user.").Required().String()
+
+  post        = app.Command("post", "Post a message to a channel.")
+  postImage   = post.Flag("image", "Image to post.").File()
+  postChannel = post.Arg("channel", "Channel to post to.").Required().String()
+  postText    = post.Arg("text", "Text to post.").Strings()
+)
+
+func main() {
+  switch kingpin.MustParse(app.Parse(os.Args[1:])) {
+  // Register user
+  case register.FullCommand():
+    println(*registerNick)
+
+  // Post message
+  case post.FullCommand():
+    if *postImage != nil {
+    }
+    text := strings.Join(*postText, " ")
+    println("Post:", text)
+  }
+}
+```
+
+## Reference Documentation
+
+### Displaying errors and usage information
+
+Kingpin exports a set of functions to provide consistent errors and usage
+information to the user.
+
+Error messages look something like this:
+
+    <app>: error: <message>
+
+The functions on `Application` are:
+
+Function | Purpose
+---------|--------------
+`Errorf(format, args)` | Display a printf formatted error to the user.
+`Fatalf(format, args)` | As with Errorf, but also call the termination handler.
+`FatalUsage(format, args)` | As with Fatalf, but also print contextual usage information.
+`FatalUsageContext(context, format, args)` | As with Fatalf, but also print contextual usage information from a `ParseContext`.
+`FatalIfError(err, format, args)` | Conditionally print an error prefixed with format+args, then call the termination handler
+
+There are equivalent global functions in the kingpin namespace for the default
+`kingpin.CommandLine` instance.
+
+### Sub-commands
+
+Kingpin supports nested sub-commands, with separate flag and positional
+arguments per sub-command. Note that positional arguments may only occur after
+sub-commands.
+
+For example:
+
+```go
+var (
+  deleteCommand     = kingpin.Command("delete", "Delete an object.")
+  deleteUserCommand = deleteCommand.Command("user", "Delete a user.")
+  deleteUserUIDFlag = deleteUserCommand.Flag("uid", "Delete user by UID rather than username.")
+  deleteUserUsername = deleteUserCommand.Arg("username", "Username to delete.")
+  deletePostCommand = deleteCommand.Command("post", "Delete a post.")
+)
+
+func main() {
+  switch kingpin.Parse() {
+  case "delete user":
+  case "delete post":
+  }
+}
+```
+
+### Custom Parsers
+
+Kingpin supports both flag and positional argument parsers for converting to
+Go types. For example, some included parsers are `Int()`, `Float()`,
+`Duration()` and `ExistingFile()` (see [parsers.go](./parsers.go) for a complete list of included parsers).
+
+Parsers conform to Go's [`flag.Value`](http://godoc.org/flag#Value)
+interface, so any existing implementations will work.
+
+For example, a parser for accumulating HTTP header values might look like this:
+
+```go
+type HTTPHeaderValue http.Header
+
+func (h *HTTPHeaderValue) Set(value string) error {
+  parts := strings.SplitN(value, ":", 2)
+  if len(parts) != 2 {
+    return fmt.Errorf("expected HEADER:VALUE got '%s'", value)
+  }
+  (*http.Header)(h).Add(parts[0], parts[1])
+  return nil
+}
+
+func (h *HTTPHeaderValue) String() string {
+  return ""
+}
+```
+
+As a convenience, I would recommend something like this:
+
+```go
+func HTTPHeader(s Settings) (target *http.Header) {
+  target = &http.Header{}
+  s.SetValue((*HTTPHeaderValue)(target))
+  return
+}
+```
+
+You would use it like so:
+
+```go
+headers = HTTPHeader(kingpin.Flag("header", "Add a HTTP header to the request.").Short('H'))
+```
+
+### Repeatable flags
+
+Depending on the `Value` they hold, some flags may be repeated. The
+`IsCumulative() bool` function on `Value` tells if it's safe to call `Set()`
+multiple times or if an error should be raised if several values are passed.
+
+The built-in `Value`s returning slices and maps, as well as `Counter` are
+examples of `Value`s that make a flag repeatable.
+
+### Boolean values
+
+Boolean values are uniquely managed by Kingpin. Each boolean flag will have a negative complement:
+`--<name>` and `--no-<name>`.
+
+### Default Values
+
+The default value is the zero value for a type. This can be overridden with
+the `Default(value...)` function on flags and arguments. This function accepts
+one or several strings, which are parsed by the value itself, so they *must*
+be compliant with the format expected.
+
+### Place-holders in Help
+
+The place-holder value for a flag is the value used in the help to describe
+the value of a non-boolean flag.
+
+The value provided to PlaceHolder() is used if provided, then the value
+provided by Default() if provided, then finally the capitalised flag name is
+used.
+
+Here are some examples of flags with various permutations:
+
+    --name=NAME           // Flag(...).String()
+    --name="Harry"        // Flag(...).Default("Harry").String()
+    --name=FULL-NAME      // flag(...).PlaceHolder("FULL-NAME").Default("Harry").String()
+
+### Consuming all remaining arguments
+
+A common command-line idiom is to use all remaining arguments for some
+purpose. eg. The following command accepts an arbitrary number of
+IP addresses as positional arguments:
+
+    ./cmd ping 10.1.1.1 192.168.1.1
+
+Such arguments are similar to [repeatable flags](#repeatable-flags), but for
+arguments. Therefore they use the same `IsCumulative() bool` function on the
+underlying `Value`, so the built-in `Value`s for which the `Set()` function
+can be called several times will consume multiple arguments.
+
+To implement the above example with a custom `Value`, we might do something
+like this:
+
+```go
+type ipList []net.IP
+
+func (i *ipList) Set(value string) error {
+  if ip := net.ParseIP(value); ip == nil {
+    return fmt.Errorf("'%s' is not an IP address", value)
+  } else {
+    *i = append(*i, ip)
+    return nil
+  }
+}
+
+func (i *ipList) String() string {
+  return ""
+}
+
+func (i *ipList) IsCumulative() bool {
+  return true
+}
+
+func IPList(s Settings) (target *[]net.IP) {
+  target = new([]net.IP)
+  s.SetValue((*ipList)(target))
+  return
+}
+```
+
+And use it like so:
+
+```go
+ips := IPList(kingpin.Arg("ips", "IP addresses to ping."))
+```
+
+### Bash/ZSH Shell Completion
+
+By default, all flags and commands/subcommands generate completions 
+internally.
+
+Out of the box, CLI tools using kingpin should be able to take advantage 
+of completion hinting for flags and commands. By specifying 
+`--completion-bash` as the first argument, your CLI tool will show 
+possible subcommands. By ending your argv with `--`, hints for flags 
+will be shown.
+
+To allow your end users to take advantage you must package a 
+`/etc/bash_completion.d` script with your distribution (or the equivalent 
+for your target platform/shell). An alternative is to instruct your end 
+user to source a script from their `bash_profile` (or equivalent).
+
+Fortunately Kingpin makes it easy to generate or source a script for use
+with end users shells. `./yourtool --completion-script-bash` and 
+`./yourtool --completion-script-zsh` will generate these scripts for you.
+
+**Installation by Package**
+
+For the best user experience, you should bundle your pre-created 
+completion script with your CLI tool and install it inside 
+`/etc/bash_completion.d` (or equivalent). A good suggestion is to add 
+this as an automated step to your build pipeline, in the implementation 
+is improved for bug fixed.
+
+**Installation by `bash_profile`**
+
+Alternatively, instruct your users to add an additional statement to 
+their `bash_profile` (or equivalent):
+
+```
+eval "$(your-cli-tool --completion-script-bash)"
+```
+
+Or for ZSH
+
+```
+eval "$(your-cli-tool --completion-script-zsh)"
+```
+
+#### Additional API
+To provide more flexibility, a completion option API has been
+exposed for flags to allow user defined completion options, to extend
+completions further than just EnumVar/Enum. 
+
+
+**Provide Static Options**
+
+When using an `Enum` or `EnumVar`, users are limited to only the options 
+given. Maybe we wish to hint possible options to the user, but also 
+allow them to provide their own custom option. `HintOptions` gives
+this functionality to flags.
+
+```
+app := kingpin.New("completion", "My application with bash completion.")
+app.Flag("port", "Provide a port to connect to").
+    Required().
+    HintOptions("80", "443", "8080").
+    IntVar(&c.port)
+```
+
+**Provide Dynamic Options**
+Consider the case that you needed to read a local database or a file to 
+provide suggestions. You can dynamically generate the options
+
+```
+func listHosts() []string {
+  // Provide a dynamic list of hosts from a hosts file or otherwise
+  // for bash completion. In this example we simply return static slice.
+
+  // You could use this functionality to reach into a hosts file to provide
+  // completion for a list of known hosts.
+  return []string{"sshhost.example", "webhost.example", "ftphost.example"}
+}
+
+app := kingpin.New("completion", "My application with bash completion.")
+app.Flag("flag-1", "").HintAction(listHosts).String()
+```
+
+**EnumVar/Enum**
+When using `Enum` or `EnumVar`, any provided options will be automatically
+used for bash autocompletion. However, if you wish to provide a subset or 
+different options, you can use `HintOptions` or `HintAction` which will override
+the default completion options for `Enum`/`EnumVar`.
+
+
+**Examples**
+You can see an in depth example of the completion API within 
+`examples/completion/main.go`
+
+
+### Supporting -h for help
+
+`kingpin.CommandLine.HelpFlag.Short('h')`
+
+### Custom help
+
+Kingpin v2 supports templatised help using the text/template library (actually, [a fork](https://github.com/alecthomas/template)).
+
+You can specify the template to use with the [Application.UsageTemplate()](http://godoc.org/gopkg.in/alecthomas/kingpin.v2#Application.UsageTemplate) function.
+
+There are four included templates: `kingpin.DefaultUsageTemplate` is the default,
+`kingpin.CompactUsageTemplate` provides a more compact representation for more complex command-line structures,
+`kingpin.SeparateOptionalFlagsUsageTemplate` looks like the default template, but splits required
+and optional command flags into separate lists, and `kingpin.ManPageTemplate` is used to generate man pages.
+
+See the above templates for examples of usage, and the the function [UsageForContextWithTemplate()](https://github.com/alecthomas/kingpin/blob/master/usage.go#L198) method for details on the context.
+
+#### Default help template
+
+```
+$ go run ./examples/curl/curl.go --help
+usage: curl [<flags>] <command> [<args> ...]
+
+An example implementation of curl.
+
+Flags:
+  --help            Show help.
+  -t, --timeout=5s  Set connection timeout.
+  -H, --headers=HEADER=VALUE
+                    Add HTTP headers to the request.
+
+Commands:
+  help [<command>...]
+    Show help.
+
+  get url <url>
+    Retrieve a URL.
+
+  get file <file>
+    Retrieve a file.
+
+  post [<flags>] <url>
+    POST a resource.
+```
+
+#### Compact help template
+
+```
+$ go run ./examples/curl/curl.go --help
+usage: curl [<flags>] <command> [<args> ...]
+
+An example implementation of curl.
+
+Flags:
+  --help            Show help.
+  -t, --timeout=5s  Set connection timeout.
+  -H, --headers=HEADER=VALUE
+                    Add HTTP headers to the request.
+
+Commands:
+  help [<command>...]
+  get [<flags>]
+    url <url>
+    file <file>
+  post [<flags>] <url>
+```

vendor/gopkg.in/alecthomas/kingpin.v2/actions.go

@@ -0,0 +1,42 @@
+package kingpin
+
+// Action callback executed at various stages after all values are populated.
+// The application, commands, arguments and flags all have corresponding
+// actions.
+type Action func(*ParseContext) error
+
+type actionMixin struct {
+	actions    []Action
+	preActions []Action
+}
+
+type actionApplier interface {
+	applyActions(*ParseContext) error
+	applyPreActions(*ParseContext) error
+}
+
+func (a *actionMixin) addAction(action Action) {
+	a.actions = append(a.actions, action)
+}
+
+func (a *actionMixin) addPreAction(action Action) {
+	a.preActions = append(a.preActions, action)
+}
+
+func (a *actionMixin) applyActions(context *ParseContext) error {
+	for _, action := range a.actions {
+		if err := action(context); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (a *actionMixin) applyPreActions(context *ParseContext) error {
+	for _, preAction := range a.preActions {
+		if err := preAction(context); err != nil {
+			return err
+		}
+	}
+	return nil
+}

vendor/gopkg.in/alecthomas/kingpin.v2/app.go

@@ -0,0 +1,685 @@
+package kingpin
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"regexp"
+	"strings"
+)
+
+var (
+	ErrCommandNotSpecified = fmt.Errorf("command not specified")
+)
+
+var (
+	envarTransformRegexp = regexp.MustCompile(`[^a-zA-Z0-9_]+`)
+)
+
+type ApplicationValidator func(*Application) error
+
+// An Application contains the definitions of flags, arguments and commands
+// for an application.
+type Application struct {
+	cmdMixin
+	initialized bool
+
+	Name string
+	Help string
+
+	author         string
+	version        string
+	errorWriter    io.Writer // Destination for errors.
+	usageWriter    io.Writer // Destination for usage
+	usageTemplate  string
+	validator      ApplicationValidator
+	terminate      func(status int) // See Terminate()
+	noInterspersed bool             // can flags be interspersed with args (or must they come first)
+	defaultEnvars  bool
+	completion     bool
+
+	// Help flag. Exposed for user customisation.
+	HelpFlag *FlagClause
+	// Help command. Exposed for user customisation. May be nil.
+	HelpCommand *CmdClause
+	// Version flag. Exposed for user customisation. May be nil.
+	VersionFlag *FlagClause
+}
+
+// New creates a new Kingpin application instance.
+func New(name, help string) *Application {
+	a := &Application{
+		Name:          name,
+		Help:          help,
+		errorWriter:   os.Stderr, // Left for backwards compatibility purposes.
+		usageWriter:   os.Stderr,
+		usageTemplate: DefaultUsageTemplate,
+		terminate:     os.Exit,
+	}
+	a.flagGroup = newFlagGroup()
+	a.argGroup = newArgGroup()
+	a.cmdGroup = newCmdGroup(a)
+	a.HelpFlag = a.Flag("help", "Show context-sensitive help (also try --help-long and --help-man).")
+	a.HelpFlag.Bool()
+	a.Flag("help-long", "Generate long help.").Hidden().PreAction(a.generateLongHelp).Bool()
+	a.Flag("help-man", "Generate a man page.").Hidden().PreAction(a.generateManPage).Bool()
+	a.Flag("completion-bash", "Output possible completions for the given args.").Hidden().BoolVar(&a.completion)
+	a.Flag("completion-script-bash", "Generate completion script for bash.").Hidden().PreAction(a.generateBashCompletionScript).Bool()
+	a.Flag("completion-script-zsh", "Generate completion script for ZSH.").Hidden().PreAction(a.generateZSHCompletionScript).Bool()
+
+	return a
+}
+
+func (a *Application) generateLongHelp(c *ParseContext) error {
+	a.Writer(os.Stdout)
+	if err := a.UsageForContextWithTemplate(c, 2, LongHelpTemplate); err != nil {
+		return err
+	}
+	a.terminate(0)
+	return nil
+}
+
+func (a *Application) generateManPage(c *ParseContext) error {
+	a.Writer(os.Stdout)
+	if err := a.UsageForContextWithTemplate(c, 2, ManPageTemplate); err != nil {
+		return err
+	}
+	a.terminate(0)
+	return nil
+}
+
+func (a *Application) generateBashCompletionScript(c *ParseContext) error {
+	a.Writer(os.Stdout)
+	if err := a.UsageForContextWithTemplate(c, 2, BashCompletionTemplate); err != nil {
+		return err
+	}
+	a.terminate(0)
+	return nil
+}
+
+func (a *Application) generateZSHCompletionScript(c *ParseContext) error {
+	a.Writer(os.Stdout)
+	if err := a.UsageForContextWithTemplate(c, 2, ZshCompletionTemplate); err != nil {
+		return err
+	}
+	a.terminate(0)
+	return nil
+}
+
+// DefaultEnvars configures all flags (that do not already have an associated
+// envar) to use a default environment variable in the form "<app>_<flag>".
+//
+// For example, if the application is named "foo" and a flag is named "bar-
+// waz" the environment variable: "FOO_BAR_WAZ".
+func (a *Application) DefaultEnvars() *Application {
+	a.defaultEnvars = true
+	return a
+}
+
+// Terminate specifies the termination handler. Defaults to os.Exit(status).
+// If nil is passed, a no-op function will be used.
+func (a *Application) Terminate(terminate func(int)) *Application {
+	if terminate == nil {
+		terminate = func(int) {}
+	}
+	a.terminate = terminate
+	return a
+}
+
+// Writer specifies the writer to use for usage and errors. Defaults to os.Stderr.
+// DEPRECATED: See ErrorWriter and UsageWriter.
+func (a *Application) Writer(w io.Writer) *Application {
+	a.errorWriter = w
+	a.usageWriter = w
+	return a
+}
+
+// ErrorWriter sets the io.Writer to use for errors.
+func (a *Application) ErrorWriter(w io.Writer) *Application {
+	a.errorWriter = w
+	return a
+}
+
+// UsageWriter sets the io.Writer to use for errors.
+func (a *Application) UsageWriter(w io.Writer) *Application {
+	a.usageWriter = w
+	return a
+}
+
+// UsageTemplate specifies the text template to use when displaying usage
+// information. The default is UsageTemplate.
+func (a *Application) UsageTemplate(template string) *Application {
+	a.usageTemplate = template
+	return a
+}
+
+// Validate sets a validation function to run when parsing.
+func (a *Application) Validate(validator ApplicationValidator) *Application {
+	a.validator = validator
+	return a
+}
+
+// ParseContext parses the given command line and returns the fully populated
+// ParseContext.
+func (a *Application) ParseContext(args []string) (*ParseContext, error) {
+	return a.parseContext(false, args)
+}
+
+func (a *Application) parseContext(ignoreDefault bool, args []string) (*ParseContext, error) {
+	if err := a.init(); err != nil {
+		return nil, err
+	}
+	context := tokenize(args, ignoreDefault)
+	err := parse(context, a)
+	return context, err
+}
+
+// Parse parses command-line arguments. It returns the selected command and an
+// error. The selected command will be a space separated subcommand, if
+// subcommands have been configured.
+//
+// This will populate all flag and argument values, call all callbacks, and so
+// on.
+func (a *Application) Parse(args []string) (command string, err error) {
+
+	context, parseErr := a.ParseContext(args)
+	selected := []string{}
+	var setValuesErr error
+
+	if context == nil {
+		// Since we do not throw error immediately, there could be a case
+		// where a context returns nil. Protect against that.
+		return "", parseErr
+	}
+
+	if err = a.setDefaults(context); err != nil {
+		return "", err
+	}
+
+	selected, setValuesErr = a.setValues(context)
+
+	if err = a.applyPreActions(context, !a.completion); err != nil {
+		return "", err
+	}
+
+	if a.completion {
+		a.generateBashCompletion(context)
+		a.terminate(0)
+	} else {
+		if parseErr != nil {
+			return "", parseErr
+		}
+
+		a.maybeHelp(context)
+		if !context.EOL() {
+			return "", fmt.Errorf("unexpected argument '%s'", context.Peek())
+		}
+
+		if setValuesErr != nil {
+			return "", setValuesErr
+		}
+
+		command, err = a.execute(context, selected)
+		if err == ErrCommandNotSpecified {
+			a.writeUsage(context, nil)
+		}
+	}
+	return command, err
+}
+
+func (a *Application) writeUsage(context *ParseContext, err error) {
+	if err != nil {
+		a.Errorf("%s", err)
+	}
+	if err := a.UsageForContext(context); err != nil {
+		panic(err)
+	}
+	if err != nil {
+		a.terminate(1)
+	} else {
+		a.terminate(0)
+	}
+}
+
+func (a *Application) maybeHelp(context *ParseContext) {
+	for _, element := range context.Elements {
+		if flag, ok := element.Clause.(*FlagClause); ok && flag == a.HelpFlag {
+			// Re-parse the command-line ignoring defaults, so that help works correctly.
+			context, _ = a.parseContext(true, context.rawArgs)
+			a.writeUsage(context, nil)
+		}
+	}
+}
+
+// Version adds a --version flag for displaying the application version.
+func (a *Application) Version(version string) *Application {
+	a.version = version
+	a.VersionFlag = a.Flag("version", "Show application version.").PreAction(func(*ParseContext) error {
+		fmt.Fprintln(a.usageWriter, version)
+		a.terminate(0)
+		return nil
+	})
+	a.VersionFlag.Bool()
+	return a
+}
+
+// Author sets the author output by some help templates.
+func (a *Application) Author(author string) *Application {
+	a.author = author
+	return a
+}
+
+// Action callback to call when all values are populated and parsing is
+// complete, but before any command, flag or argument actions.
+//
+// All Action() callbacks are called in the order they are encountered on the
+// command line.
+func (a *Application) Action(action Action) *Application {
+	a.addAction(action)
+	return a
+}
+
+// Action called after parsing completes but before validation and execution.
+func (a *Application) PreAction(action Action) *Application {
+	a.addPreAction(action)
+	return a
+}
+
+// Command adds a new top-level command.
+func (a *Application) Command(name, help string) *CmdClause {
+	return a.addCommand(name, help)
+}
+
+// Interspersed control if flags can be interspersed with positional arguments
+//
+// true (the default) means that they can, false means that all the flags must appear before the first positional arguments.
+func (a *Application) Interspersed(interspersed bool) *Application {
+	a.noInterspersed = !interspersed
+	return a
+}
+
+func (a *Application) defaultEnvarPrefix() string {
+	if a.defaultEnvars {
+		return a.Name
+	}
+	return ""
+}
+
+func (a *Application) init() error {
+	if a.initialized {
+		return nil
+	}
+	if a.cmdGroup.have() && a.argGroup.have() {
+		return fmt.Errorf("can't mix top-level Arg()s with Command()s")
+	}
+
+	// If we have subcommands, add a help command at the top-level.
+	if a.cmdGroup.have() {
+		var command []string
+		a.HelpCommand = a.Command("help", "Show help.").PreAction(func(context *ParseContext) error {
+			a.Usage(command)
+			a.terminate(0)
+			return nil
+		})
+		a.HelpCommand.Arg("command", "Show help on command.").StringsVar(&command)
+		// Make help first command.
+		l := len(a.commandOrder)
+		a.commandOrder = append(a.commandOrder[l-1:l], a.commandOrder[:l-1]...)
+	}
+
+	if err := a.flagGroup.init(a.defaultEnvarPrefix()); err != nil {
+		return err
+	}
+	if err := a.cmdGroup.init(); err != nil {
+		return err
+	}
+	if err := a.argGroup.init(); err != nil {
+		return err
+	}
+	for _, cmd := range a.commands {
+		if err := cmd.init(); err != nil {
+			return err
+		}
+	}
+	flagGroups := []*flagGroup{a.flagGroup}
+	for _, cmd := range a.commandOrder {
+		if err := checkDuplicateFlags(cmd, flagGroups); err != nil {
+			return err
+		}
+	}
+	a.initialized = true
+	return nil
+}
+
+// Recursively check commands for duplicate flags.
+func checkDuplicateFlags(current *CmdClause, flagGroups []*flagGroup) error {
+	// Check for duplicates.
+	for _, flags := range flagGroups {
+		for _, flag := range current.flagOrder {
+			if flag.shorthand != 0 {
+				if _, ok := flags.short[string(flag.shorthand)]; ok {
+					return fmt.Errorf("duplicate short flag -%c", flag.shorthand)
+				}
+			}
+			if _, ok := flags.long[flag.name]; ok {
+				return fmt.Errorf("duplicate long flag --%s", flag.name)
+			}
+		}
+	}
+	flagGroups = append(flagGroups, current.flagGroup)
+	// Check subcommands.
+	for _, subcmd := range current.commandOrder {
+		if err := checkDuplicateFlags(subcmd, flagGroups); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (a *Application) execute(context *ParseContext, selected []string) (string, error) {
+	var err error
+
+	if err = a.validateRequired(context); err != nil {
+		return "", err
+	}
+
+	if err = a.applyValidators(context); err != nil {
+		return "", err
+	}
+
+	if err = a.applyActions(context); err != nil {
+		return "", err
+	}
+
+	command := strings.Join(selected, " ")
+	if command == "" && a.cmdGroup.have() {
+		return "", ErrCommandNotSpecified
+	}
+	return command, err
+}
+
+func (a *Application) setDefaults(context *ParseContext) error {
+	flagElements := map[string]*ParseElement{}
+	for _, element := range context.Elements {
+		if flag, ok := element.Clause.(*FlagClause); ok {
+			flagElements[flag.name] = element
+		}
+	}
+
+	argElements := map[string]*ParseElement{}
+	for _, element := range context.Elements {
+		if arg, ok := element.Clause.(*ArgClause); ok {
+			argElements[arg.name] = element
+		}
+	}
+
+	// Check required flags and set defaults.
+	for _, flag := range context.flags.long {
+		if flagElements[flag.name] == nil {
+			if err := flag.setDefault(); err != nil {
+				return err
+			}
+		}
+	}
+
+	for _, arg := range context.arguments.args {
+		if argElements[arg.name] == nil {
+			if err := arg.setDefault(); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func (a *Application) validateRequired(context *ParseContext) error {
+	flagElements := map[string]*ParseElement{}
+	for _, element := range context.Elements {
+		if flag, ok := element.Clause.(*FlagClause); ok {
+			flagElements[flag.name] = element
+		}
+	}
+
+	argElements := map[string]*ParseElement{}
+	for _, element := range context.Elements {
+		if arg, ok := element.Clause.(*ArgClause); ok {
+			argElements[arg.name] = element
+		}
+	}
+
+	// Check required flags and set defaults.
+	for _, flag := range context.flags.long {
+		if flagElements[flag.name] == nil {
+			// Check required flags were provided.
+			if flag.needsValue() {
+				return fmt.Errorf("required flag --%s not provided", flag.name)
+			}
+		}
+	}
+
+	for _, arg := range context.arguments.args {
+		if argElements[arg.name] == nil {
+			if arg.needsValue() {
+				return fmt.Errorf("required argument '%s' not provided", arg.name)
+			}
+		}
+	}
+	return nil
+}
+
+func (a *Application) setValues(context *ParseContext) (selected []string, err error) {
+	// Set all arg and flag values.
+	var (
+		lastCmd *CmdClause
+		flagSet = map[string]struct{}{}
+	)
+	for _, element := range context.Elements {
+		switch clause := element.Clause.(type) {
+		case *FlagClause:
+			if _, ok := flagSet[clause.name]; ok {
+				if v, ok := clause.value.(repeatableFlag); !ok || !v.IsCumulative() {
+					return nil, fmt.Errorf("flag '%s' cannot be repeated", clause.name)
+				}
+			}
+			if err = clause.value.Set(*element.Value); err != nil {
+				return
+			}
+			flagSet[clause.name] = struct{}{}
+
+		case *ArgClause:
+			if err = clause.value.Set(*element.Value); err != nil {
+				return
+			}
+
+		case *CmdClause:
+			if clause.validator != nil {
+				if err = clause.validator(clause); err != nil {
+					return
+				}
+			}
+			selected = append(selected, clause.name)
+			lastCmd = clause
+		}
+	}
+
+	if lastCmd != nil && len(lastCmd.commands) > 0 {
+		return nil, fmt.Errorf("must select a subcommand of '%s'", lastCmd.FullCommand())
+	}
+
+	return
+}
+
+func (a *Application) applyValidators(context *ParseContext) (err error) {
+	// Call command validation functions.
+	for _, element := range context.Elements {
+		if cmd, ok := element.Clause.(*CmdClause); ok && cmd.validator != nil {
+			if err = cmd.validator(cmd); err != nil {
+				return err
+			}
+		}
+	}
+
+	if a.validator != nil {
+		err = a.validator(a)
+	}
+	return err
+}
+
+func (a *Application) applyPreActions(context *ParseContext, dispatch bool) error {
+	if err := a.actionMixin.applyPreActions(context); err != nil {
+		return err
+	}
+	// Dispatch to actions.
+	if dispatch {
+		for _, element := range context.Elements {
+			if applier, ok := element.Clause.(actionApplier); ok {
+				if err := applier.applyPreActions(context); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func (a *Application) applyActions(context *ParseContext) error {
+	if err := a.actionMixin.applyActions(context); err != nil {
+		return err
+	}
+	// Dispatch to actions.
+	for _, element := range context.Elements {
+		if applier, ok := element.Clause.(actionApplier); ok {
+			if err := applier.applyActions(context); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// Errorf prints an error message to w in the format "<appname>: error: <message>".
+func (a *Application) Errorf(format string, args ...interface{}) {
+	fmt.Fprintf(a.errorWriter, a.Name+": error: "+format+"\n", args...)
+}
+
+// Fatalf writes a formatted error to w then terminates with exit status 1.
+func (a *Application) Fatalf(format string, args ...interface{}) {
+	a.Errorf(format, args...)
+	a.terminate(1)
+}
+
+// FatalUsage prints an error message followed by usage information, then
+// exits with a non-zero status.
+func (a *Application) FatalUsage(format string, args ...interface{}) {
+	a.Errorf(format, args...)
+	// Force usage to go to error output.
+	a.usageWriter = a.errorWriter
+	a.Usage([]string{})
+	a.terminate(1)
+}
+
+// FatalUsageContext writes a printf formatted error message to w, then usage
+// information for the given ParseContext, before exiting.
+func (a *Application) FatalUsageContext(context *ParseContext, format string, args ...interface{}) {
+	a.Errorf(format, args...)
+	if err := a.UsageForContext(context); err != nil {
+		panic(err)
+	}
+	a.terminate(1)
+}
+
+// FatalIfError prints an error and exits if err is not nil. The error is printed
+// with the given formatted string, if any.
+func (a *Application) FatalIfError(err error, format string, args ...interface{}) {
+	if err != nil {
+		prefix := ""
+		if format != "" {
+			prefix = fmt.Sprintf(format, args...) + ": "
+		}
+		a.Errorf(prefix+"%s", err)
+		a.terminate(1)
+	}
+}
+
+func (a *Application) completionOptions(context *ParseContext) []string {
+	args := context.rawArgs
+
+	var (
+		currArg string
+		prevArg string
+		target  cmdMixin
+	)
+
+	numArgs := len(args)
+	if numArgs > 1 {
+		args = args[1:]
+		currArg = args[len(args)-1]
+	}
+	if numArgs > 2 {
+		prevArg = args[len(args)-2]
+	}
+
+	target = a.cmdMixin
+	if context.SelectedCommand != nil {
+		// A subcommand was in use. We will use it as the target
+		target = context.SelectedCommand.cmdMixin
+	}
+
+	if (currArg != "" && strings.HasPrefix(currArg, "--")) || strings.HasPrefix(prevArg, "--") {
+		// Perform completion for A flag. The last/current argument started with "-"
+		var (
+			flagName  string // The name of a flag if given (could be half complete)
+			flagValue string // The value assigned to a flag (if given) (could be half complete)
+		)
+
+		if strings.HasPrefix(prevArg, "--") && !strings.HasPrefix(currArg, "--") {
+			// Matches: 	./myApp --flag value
+			// Wont Match: 	./myApp --flag --
+			flagName = prevArg[2:] // Strip the "--"
+			flagValue = currArg
+		} else if strings.HasPrefix(currArg, "--") {
+			// Matches: 	./myApp --flag --
+			// Matches:		./myApp --flag somevalue --
+			// Matches: 	./myApp --
+			flagName = currArg[2:] // Strip the "--"
+		}
+
+		options, flagMatched, valueMatched := target.FlagCompletion(flagName, flagValue)
+		if valueMatched {
+			// Value Matched. Show cmdCompletions
+			return target.CmdCompletion(context)
+		}
+
+		// Add top level flags if we're not at the top level and no match was found.
+		if context.SelectedCommand != nil && !flagMatched {
+			topOptions, topFlagMatched, topValueMatched := a.FlagCompletion(flagName, flagValue)
+			if topValueMatched {
+				// Value Matched. Back to cmdCompletions
+				return target.CmdCompletion(context)
+			}
+
+			if topFlagMatched {
+				// Top level had a flag which matched the input. Return it's options.
+				options = topOptions
+			} else {
+				// Add top level flags
+				options = append(options, topOptions...)
+			}
+		}
+		return options
+	}
+
+	// Perform completion for sub commands and arguments.
+	return target.CmdCompletion(context)
+}
+
+func (a *Application) generateBashCompletion(context *ParseContext) {
+	options := a.completionOptions(context)
+	fmt.Printf("%s", strings.Join(options, "\n"))
+}
+
+func envarTransform(name string) string {
+	return strings.ToUpper(envarTransformRegexp.ReplaceAllString(name, "_"))
+}

vendor/gopkg.in/alecthomas/kingpin.v2/args.go

@@ -0,0 +1,184 @@
+package kingpin
+
+import (
+	"fmt"
+)
+
+type argGroup struct {
+	args []*ArgClause
+}
+
+func newArgGroup() *argGroup {
+	return &argGroup{}
+}
+
+func (a *argGroup) have() bool {
+	return len(a.args) > 0
+}
+
+// GetArg gets an argument definition.
+//
+// This allows existing arguments to be modified after definition but before parsing. Useful for
+// modular applications.
+func (a *argGroup) GetArg(name string) *ArgClause {
+	for _, arg := range a.args {
+		if arg.name == name {
+			return arg
+		}
+	}
+	return nil
+}
+
+func (a *argGroup) Arg(name, help string) *ArgClause {
+	arg := newArg(name, help)
+	a.args = append(a.args, arg)
+	return arg
+}
+
+func (a *argGroup) init() error {
+	required := 0
+	seen := map[string]struct{}{}
+	previousArgMustBeLast := false
+	for i, arg := range a.args {
+		if previousArgMustBeLast {
+			return fmt.Errorf("Args() can't be followed by another argument '%s'", arg.name)
+		}
+		if arg.consumesRemainder() {
+			previousArgMustBeLast = true
+		}
+		if _, ok := seen[arg.name]; ok {
+			return fmt.Errorf("duplicate argument '%s'", arg.name)
+		}
+		seen[arg.name] = struct{}{}
+		if arg.required && required != i {
+			return fmt.Errorf("required arguments found after non-required")
+		}
+		if arg.required {
+			required++
+		}
+		if err := arg.init(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+type ArgClause struct {
+	actionMixin
+	parserMixin
+	completionsMixin
+	envarMixin
+	name          string
+	help          string
+	defaultValues []string
+	required      bool
+}
+
+func newArg(name, help string) *ArgClause {
+	a := &ArgClause{
+		name: name,
+		help: help,
+	}
+	return a
+}
+
+func (a *ArgClause) setDefault() error {
+	if a.HasEnvarValue() {
+		if v, ok := a.value.(remainderArg); !ok || !v.IsCumulative() {
+			// Use the value as-is
+			return a.value.Set(a.GetEnvarValue())
+		}
+		for _, value := range a.GetSplitEnvarValue() {
+			if err := a.value.Set(value); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	if len(a.defaultValues) > 0 {
+		for _, defaultValue := range a.defaultValues {
+			if err := a.value.Set(defaultValue); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	return nil
+}
+
+func (a *ArgClause) needsValue() bool {
+	haveDefault := len(a.defaultValues) > 0
+	return a.required && !(haveDefault || a.HasEnvarValue())
+}
+
+func (a *ArgClause) consumesRemainder() bool {
+	if r, ok := a.value.(remainderArg); ok {
+		return r.IsCumulative()
+	}
+	return false
+}
+
+// Required arguments must be input by the user. They can not have a Default() value provided.
+func (a *ArgClause) Required() *ArgClause {
+	a.required = true
+	return a
+}
+
+// Default values for this argument. They *must* be parseable by the value of the argument.
+func (a *ArgClause) Default(values ...string) *ArgClause {
+	a.defaultValues = values
+	return a
+}
+
+// Envar overrides the default value(s) for a flag from an environment variable,
+// if it is set. Several default values can be provided by using new lines to
+// separate them.
+func (a *ArgClause) Envar(name string) *ArgClause {
+	a.envar = name
+	a.noEnvar = false
+	return a
+}
+
+// NoEnvar forces environment variable defaults to be disabled for this flag.
+// Most useful in conjunction with app.DefaultEnvars().
+func (a *ArgClause) NoEnvar() *ArgClause {
+	a.envar = ""
+	a.noEnvar = true
+	return a
+}
+
+func (a *ArgClause) Action(action Action) *ArgClause {
+	a.addAction(action)
+	return a
+}
+
+func (a *ArgClause) PreAction(action Action) *ArgClause {
+	a.addPreAction(action)
+	return a
+}
+
+// HintAction registers a HintAction (function) for the arg to provide completions
+func (a *ArgClause) HintAction(action HintAction) *ArgClause {
+	a.addHintAction(action)
+	return a
+}
+
+// HintOptions registers any number of options for the flag to provide completions
+func (a *ArgClause) HintOptions(options ...string) *ArgClause {
+	a.addHintAction(func() []string {
+		return options
+	})
+	return a
+}
+
+func (a *ArgClause) init() error {
+	if a.required && len(a.defaultValues) > 0 {
+		return fmt.Errorf("required argument '%s' with unusable default value", a.name)
+	}
+	if a.value == nil {
+		return fmt.Errorf("no parser defined for arg '%s'", a.name)
+	}
+	return nil
+}

vendor/gopkg.in/alecthomas/kingpin.v2/cmd.go

@@ -0,0 +1,274 @@
+package kingpin
+
+import (
+	"fmt"
+	"strings"
+)
+
+type cmdMixin struct {
+	*flagGroup
+	*argGroup
+	*cmdGroup
+	actionMixin
+}
+
+// CmdCompletion returns completion options for arguments, if that's where
+// parsing left off, or commands if there aren't any unsatisfied args.
+func (c *cmdMixin) CmdCompletion(context *ParseContext) []string {
+	var options []string
+
+	// Count args already satisfied - we won't complete those, and add any
+	// default commands' alternatives, since they weren't listed explicitly
+	// and the user may want to explicitly list something else.
+	argsSatisfied := 0
+	for _, el := range context.Elements {
+		switch clause := el.Clause.(type) {
+		case *ArgClause:
+			if el.Value != nil && *el.Value != "" {
+				argsSatisfied++
+			}
+		case *CmdClause:
+			options = append(options, clause.completionAlts...)
+		default:
+		}
+	}
+
+	if argsSatisfied < len(c.argGroup.args) {
+		// Since not all args have been satisfied, show options for the current one
+		options = append(options, c.argGroup.args[argsSatisfied].resolveCompletions()...)
+	} else {
+		// If all args are satisfied, then go back to completing commands
+		for _, cmd := range c.cmdGroup.commandOrder {
+			if !cmd.hidden {
+				options = append(options, cmd.name)
+			}
+		}
+	}
+
+	return options
+}
+
+func (c *cmdMixin) FlagCompletion(flagName string, flagValue string) (choices []string, flagMatch bool, optionMatch bool) {
+	// Check if flagName matches a known flag.
+	// If it does, show the options for the flag
+	// Otherwise, show all flags
+
+	options := []string{}
+
+	for _, flag := range c.flagGroup.flagOrder {
+		// Loop through each flag and determine if a match exists
+		if flag.name == flagName {
+			// User typed entire flag. Need to look for flag options.
+			options = flag.resolveCompletions()
+			if len(options) == 0 {
+				// No Options to Choose From, Assume Match.
+				return options, true, true
+			}
+
+			// Loop options to find if the user specified value matches
+			isPrefix := false
+			matched := false
+
+			for _, opt := range options {
+				if flagValue == opt {
+					matched = true
+				} else if strings.HasPrefix(opt, flagValue) {
+					isPrefix = true
+				}
+			}
+
+			// Matched Flag Directly
+			// Flag Value Not Prefixed, and Matched Directly
+			return options, true, !isPrefix && matched
+		}
+
+		if !flag.hidden {
+			options = append(options, "--"+flag.name)
+		}
+	}
+	// No Flag directly matched.
+	return options, false, false
+
+}
+
+type cmdGroup struct {
+	app          *Application
+	parent       *CmdClause
+	commands     map[string]*CmdClause
+	commandOrder []*CmdClause
+}
+
+func (c *cmdGroup) defaultSubcommand() *CmdClause {
+	for _, cmd := range c.commandOrder {
+		if cmd.isDefault {
+			return cmd
+		}
+	}
+	return nil
+}
+
+func (c *cmdGroup) cmdNames() []string {
+	names := make([]string, 0, len(c.commandOrder))
+	for _, cmd := range c.commandOrder {
+		names = append(names, cmd.name)
+	}
+	return names
+}
+
+// GetArg gets a command definition.
+//
+// This allows existing commands to be modified after definition but before parsing. Useful for
+// modular applications.
+func (c *cmdGroup) GetCommand(name string) *CmdClause {
+	return c.commands[name]
+}
+
+func newCmdGroup(app *Application) *cmdGroup {
+	return &cmdGroup{
+		app:      app,
+		commands: make(map[string]*CmdClause),
+	}
+}
+
+func (c *cmdGroup) flattenedCommands() (out []*CmdClause) {
+	for _, cmd := range c.commandOrder {
+		if len(cmd.commands) == 0 {
+			out = append(out, cmd)
+		}
+		out = append(out, cmd.flattenedCommands()...)
+	}
+	return
+}
+
+func (c *cmdGroup) addCommand(name, help string) *CmdClause {
+	cmd := newCommand(c.app, name, help)
+	c.commands[name] = cmd
+	c.commandOrder = append(c.commandOrder, cmd)
+	return cmd
+}
+
+func (c *cmdGroup) init() error {
+	seen := map[string]bool{}
+	if c.defaultSubcommand() != nil && !c.have() {
+		return fmt.Errorf("default subcommand %q provided but no subcommands defined", c.defaultSubcommand().name)
+	}
+	defaults := []string{}
+	for _, cmd := range c.commandOrder {
+		if cmd.isDefault {
+			defaults = append(defaults, cmd.name)
+		}
+		if seen[cmd.name] {
+			return fmt.Errorf("duplicate command %q", cmd.name)
+		}
+		seen[cmd.name] = true
+		for _, alias := range cmd.aliases {
+			if seen[alias] {
+				return fmt.Errorf("alias duplicates existing command %q", alias)
+			}
+			c.commands[alias] = cmd
+		}
+		if err := cmd.init(); err != nil {
+			return err
+		}
+	}
+	if len(defaults) > 1 {
+		return fmt.Errorf("more than one default subcommand exists: %s", strings.Join(defaults, ", "))
+	}
+	return nil
+}
+
+func (c *cmdGroup) have() bool {
+	return len(c.commands) > 0
+}
+
+type CmdClauseValidator func(*CmdClause) error
+
+// A CmdClause is a single top-level command. It encapsulates a set of flags
+// and either subcommands or positional arguments.
+type CmdClause struct {
+	cmdMixin
+	app            *Application
+	name           string
+	aliases        []string
+	help           string
+	isDefault      bool
+	validator      CmdClauseValidator
+	hidden         bool
+	completionAlts []string
+}
+
+func newCommand(app *Application, name, help string) *CmdClause {
+	c := &CmdClause{
+		app:  app,
+		name: name,
+		help: help,
+	}
+	c.flagGroup = newFlagGroup()
+	c.argGroup = newArgGroup()
+	c.cmdGroup = newCmdGroup(app)
+	return c
+}
+
+// Add an Alias for this command.
+func (c *CmdClause) Alias(name string) *CmdClause {
+	c.aliases = append(c.aliases, name)
+	return c
+}
+
+// Validate sets a validation function to run when parsing.
+func (c *CmdClause) Validate(validator CmdClauseValidator) *CmdClause {
+	c.validator = validator
+	return c
+}
+
+func (c *CmdClause) FullCommand() string {
+	out := []string{c.name}
+	for p := c.parent; p != nil; p = p.parent {
+		out = append([]string{p.name}, out...)
+	}
+	return strings.Join(out, " ")
+}
+
+// Command adds a new sub-command.
+func (c *CmdClause) Command(name, help string) *CmdClause {
+	cmd := c.addCommand(name, help)
+	cmd.parent = c
+	return cmd
+}
+
+// Default makes this command the default if commands don't match.
+func (c *CmdClause) Default() *CmdClause {
+	c.isDefault = true
+	return c
+}
+
+func (c *CmdClause) Action(action Action) *CmdClause {
+	c.addAction(action)
+	return c
+}
+
+func (c *CmdClause) PreAction(action Action) *CmdClause {
+	c.addPreAction(action)
+	return c
+}
+
+func (c *CmdClause) init() error {
+	if err := c.flagGroup.init(c.app.defaultEnvarPrefix()); err != nil {
+		return err
+	}
+	if c.argGroup.have() && c.cmdGroup.have() {
+		return fmt.Errorf("can't mix Arg()s with Command()s")
+	}
+	if err := c.argGroup.init(); err != nil {
+		return err
+	}
+	if err := c.cmdGroup.init(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (c *CmdClause) Hidden() *CmdClause {
+	c.hidden = true
+	return c
+}

vendor/gopkg.in/alecthomas/kingpin.v2/completions.go

@@ -0,0 +1,33 @@
+package kingpin
+
+// HintAction is a function type who is expected to return a slice of possible
+// command line arguments.
+type HintAction func() []string
+type completionsMixin struct {
+	hintActions        []HintAction
+	builtinHintActions []HintAction
+}
+
+func (a *completionsMixin) addHintAction(action HintAction) {
+	a.hintActions = append(a.hintActions, action)
+}
+
+// Allow adding of HintActions which are added internally, ie, EnumVar
+func (a *completionsMixin) addHintActionBuiltin(action HintAction) {
+	a.builtinHintActions = append(a.builtinHintActions, action)
+}
+
+func (a *completionsMixin) resolveCompletions() []string {
+	var hints []string
+
+	options := a.builtinHintActions
+	if len(a.hintActions) > 0 {
+		// User specified their own hintActions. Use those instead.
+		options = a.hintActions
+	}
+
+	for _, hintAction := range options {
+		hints = append(hints, hintAction()...)
+	}
+	return hints
+}

vendor/gopkg.in/alecthomas/kingpin.v2/doc.go

@@ -0,0 +1,68 @@
+// Package kingpin provides command line interfaces like this:
+//
+//     $ chat
+//     usage: chat [<flags>] <command> [<flags>] [<args> ...]
+//
+//     Flags:
+//       --debug              enable debug mode
+//       --help               Show help.
+//       --server=127.0.0.1   server address
+//
+//     Commands:
+//       help <command>
+//         Show help for a command.
+//
+//       post [<flags>] <channel>
+//         Post a message to a channel.
+//
+//       register <nick> <name>
+//         Register a new user.
+//
+//     $ chat help post
+//     usage: chat [<flags>] post [<flags>] <channel> [<text>]
+//
+//     Post a message to a channel.
+//
+//     Flags:
+//       --image=IMAGE   image to post
+//
+//     Args:
+//       <channel>   channel to post to
+//       [<text>]    text to post
+//     $ chat post --image=~/Downloads/owls.jpg pics
+//
+// From code like this:
+//
+//     package main
+//
+//     import "gopkg.in/alecthomas/kingpin.v2"
+//
+//     var (
+//       debug    = kingpin.Flag("debug", "enable debug mode").Default("false").Bool()
+//       serverIP = kingpin.Flag("server", "server address").Default("127.0.0.1").IP()
+//
+//       register     = kingpin.Command("register", "Register a new user.")
+//       registerNick = register.Arg("nick", "nickname for user").Required().String()
+//       registerName = register.Arg("name", "name of user").Required().String()
+//
+//       post        = kingpin.Command("post", "Post a message to a channel.")
+//       postImage   = post.Flag("image", "image to post").ExistingFile()
+//       postChannel = post.Arg("channel", "channel to post to").Required().String()
+//       postText    = post.Arg("text", "text to post").String()
+//     )
+//
+//     func main() {
+//       switch kingpin.Parse() {
+//       // Register user
+//       case "register":
+//         println(*registerNick)
+//
+//       // Post message
+//       case "post":
+//         if *postImage != nil {
+//         }
+//         if *postText != "" {
+//         }
+//       }
+//     }
+package kingpin

vendor/gopkg.in/alecthomas/kingpin.v2/envar.go

@@ -0,0 +1,45 @@
+package kingpin
+
+import (
+	"os"
+	"regexp"
+)
+
+var (
+	envVarValuesSeparator = "\r?\n"
+	envVarValuesTrimmer   = regexp.MustCompile(envVarValuesSeparator + "$")
+	envVarValuesSplitter  = regexp.MustCompile(envVarValuesSeparator)
+)
+
+type envarMixin struct {
+	envar   string
+	noEnvar bool
+}
+
+func (e *envarMixin) HasEnvarValue() bool {
+	return e.GetEnvarValue() != ""
+}
+
+func (e *envarMixin) GetEnvarValue() string {
+	if e.noEnvar || e.envar == "" {
+		return ""
+	}
+	return os.Getenv(e.envar)
+}
+
+func (e *envarMixin) GetSplitEnvarValue() []string {
+	values := make([]string, 0)
+
+	envarValue := e.GetEnvarValue()
+	if envarValue == "" {
+		return values
+	}
+
+	// Split by new line to extract multiple values, if any.
+	trimmed := envVarValuesTrimmer.ReplaceAllString(envarValue, "")
+	for _, value := range envVarValuesSplitter.Split(trimmed, -1) {
+		values = append(values, value)
+	}
+
+	return values
+}

vendor/gopkg.in/alecthomas/kingpin.v2/flags.go

@@ -0,0 +1,308 @@
+package kingpin
+
+import (
+	"fmt"
+	"strings"
+)
+
+type flagGroup struct {
+	short     map[string]*FlagClause
+	long      map[string]*FlagClause
+	flagOrder []*FlagClause
+}
+
+func newFlagGroup() *flagGroup {
+	return &flagGroup{
+		short: map[string]*FlagClause{},
+		long:  map[string]*FlagClause{},
+	}
+}
+
+// GetFlag gets a flag definition.
+//
+// This allows existing flags to be modified after definition but before parsing. Useful for
+// modular applications.
+func (f *flagGroup) GetFlag(name string) *FlagClause {
+	return f.long[name]
+}
+
+// Flag defines a new flag with the given long name and help.
+func (f *flagGroup) Flag(name, help string) *FlagClause {
+	flag := newFlag(name, help)
+	f.long[name] = flag
+	f.flagOrder = append(f.flagOrder, flag)
+	return flag
+}
+
+func (f *flagGroup) init(defaultEnvarPrefix string) error {
+	if err := f.checkDuplicates(); err != nil {
+		return err
+	}
+	for _, flag := range f.long {
+		if defaultEnvarPrefix != "" && !flag.noEnvar && flag.envar == "" {
+			flag.envar = envarTransform(defaultEnvarPrefix + "_" + flag.name)
+		}
+		if err := flag.init(); err != nil {
+			return err
+		}
+		if flag.shorthand != 0 {
+			f.short[string(flag.shorthand)] = flag
+		}
+	}
+	return nil
+}
+
+func (f *flagGroup) checkDuplicates() error {
+	seenShort := map[rune]bool{}
+	seenLong := map[string]bool{}
+	for _, flag := range f.flagOrder {
+		if flag.shorthand != 0 {
+			if _, ok := seenShort[flag.shorthand]; ok {
+				return fmt.Errorf("duplicate short flag -%c", flag.shorthand)
+			}
+			seenShort[flag.shorthand] = true
+		}
+		if _, ok := seenLong[flag.name]; ok {
+			return fmt.Errorf("duplicate long flag --%s", flag.name)
+		}
+		seenLong[flag.name] = true
+	}
+	return nil
+}
+
+func (f *flagGroup) parse(context *ParseContext) (*FlagClause, error) {
+	var token *Token
+
+loop:
+	for {
+		token = context.Peek()
+		switch token.Type {
+		case TokenEOL:
+			break loop
+
+		case TokenLong, TokenShort:
+			flagToken := token
+			defaultValue := ""
+			var flag *FlagClause
+			var ok bool
+			invert := false
+
+			name := token.Value
+			if token.Type == TokenLong {
+				flag, ok = f.long[name]
+				if !ok {
+					if strings.HasPrefix(name, "no-") {
+						name = name[3:]
+						invert = true
+					}
+					flag, ok = f.long[name]
+				}
+				if !ok {
+					return nil, fmt.Errorf("unknown long flag '%s'", flagToken)
+				}
+			} else {
+				flag, ok = f.short[name]
+				if !ok {
+					return nil, fmt.Errorf("unknown short flag '%s'", flagToken)
+				}
+			}
+
+			context.Next()
+
+			fb, ok := flag.value.(boolFlag)
+			if ok && fb.IsBoolFlag() {
+				if invert {
+					defaultValue = "false"
+				} else {
+					defaultValue = "true"
+				}
+			} else {
+				if invert {
+					context.Push(token)
+					return nil, fmt.Errorf("unknown long flag '%s'", flagToken)
+				}
+				token = context.Peek()
+				if token.Type != TokenArg {
+					context.Push(token)
+					return nil, fmt.Errorf("expected argument for flag '%s'", flagToken)
+				}
+				context.Next()
+				defaultValue = token.Value
+			}
+
+			context.matchedFlag(flag, defaultValue)
+			return flag, nil
+
+		default:
+			break loop
+		}
+	}
+	return nil, nil
+}
+
+// FlagClause is a fluid interface used to build flags.
+type FlagClause struct {
+	parserMixin
+	actionMixin
+	completionsMixin
+	envarMixin
+	name          string
+	shorthand     rune
+	help          string
+	defaultValues []string
+	placeholder   string
+	hidden        bool
+}
+
+func newFlag(name, help string) *FlagClause {
+	f := &FlagClause{
+		name: name,
+		help: help,
+	}
+	return f
+}
+
+func (f *FlagClause) setDefault() error {
+	if f.HasEnvarValue() {
+		if v, ok := f.value.(repeatableFlag); !ok || !v.IsCumulative() {
+			// Use the value as-is
+			return f.value.Set(f.GetEnvarValue())
+		} else {
+			for _, value := range f.GetSplitEnvarValue() {
+				if err := f.value.Set(value); err != nil {
+					return err
+				}
+			}
+			return nil
+		}
+	}
+
+	if len(f.defaultValues) > 0 {
+		for _, defaultValue := range f.defaultValues {
+			if err := f.value.Set(defaultValue); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	return nil
+}
+
+func (f *FlagClause) needsValue() bool {
+	haveDefault := len(f.defaultValues) > 0
+	return f.required && !(haveDefault || f.HasEnvarValue())
+}
+
+func (f *FlagClause) init() error {
+	if f.required && len(f.defaultValues) > 0 {
+		return fmt.Errorf("required flag '--%s' with default value that will never be used", f.name)
+	}
+	if f.value == nil {
+		return fmt.Errorf("no type defined for --%s (eg. .String())", f.name)
+	}
+	if v, ok := f.value.(repeatableFlag); (!ok || !v.IsCumulative()) && len(f.defaultValues) > 1 {
+		return fmt.Errorf("invalid default for '--%s', expecting single value", f.name)
+	}
+	return nil
+}
+
+// Dispatch to the given function after the flag is parsed and validated.
+func (f *FlagClause) Action(action Action) *FlagClause {
+	f.addAction(action)
+	return f
+}
+
+func (f *FlagClause) PreAction(action Action) *FlagClause {
+	f.addPreAction(action)
+	return f
+}
+
+// HintAction registers a HintAction (function) for the flag to provide completions
+func (a *FlagClause) HintAction(action HintAction) *FlagClause {
+	a.addHintAction(action)
+	return a
+}
+
+// HintOptions registers any number of options for the flag to provide completions
+func (a *FlagClause) HintOptions(options ...string) *FlagClause {
+	a.addHintAction(func() []string {
+		return options
+	})
+	return a
+}
+
+func (a *FlagClause) EnumVar(target *string, options ...string) {
+	a.parserMixin.EnumVar(target, options...)
+	a.addHintActionBuiltin(func() []string {
+		return options
+	})
+}
+
+func (a *FlagClause) Enum(options ...string) (target *string) {
+	a.addHintActionBuiltin(func() []string {
+		return options
+	})
+	return a.parserMixin.Enum(options...)
+}
+
+// Default values for this flag. They *must* be parseable by the value of the flag.
+func (f *FlagClause) Default(values ...string) *FlagClause {
+	f.defaultValues = values
+	return f
+}
+
+// DEPRECATED: Use Envar(name) instead.
+func (f *FlagClause) OverrideDefaultFromEnvar(envar string) *FlagClause {
+	return f.Envar(envar)
+}
+
+// Envar overrides the default value(s) for a flag from an environment variable,
+// if it is set. Several default values can be provided by using new lines to
+// separate them.
+func (f *FlagClause) Envar(name string) *FlagClause {
+	f.envar = name
+	f.noEnvar = false
+	return f
+}
+
+// NoEnvar forces environment variable defaults to be disabled for this flag.
+// Most useful in conjunction with app.DefaultEnvars().
+func (f *FlagClause) NoEnvar() *FlagClause {
+	f.envar = ""
+	f.noEnvar = true
+	return f
+}
+
+// PlaceHolder sets the place-holder string used for flag values in the help. The
+// default behaviour is to use the value provided by Default() if provided,
+// then fall back on the capitalized flag name.
+func (f *FlagClause) PlaceHolder(placeholder string) *FlagClause {
+	f.placeholder = placeholder
+	return f
+}
+
+// Hidden hides a flag from usage but still allows it to be used.
+func (f *FlagClause) Hidden() *FlagClause {
+	f.hidden = true
+	return f
+}
+
+// Required makes the flag required. You can not provide a Default() value to a Required() flag.
+func (f *FlagClause) Required() *FlagClause {
+	f.required = true
+	return f
+}
+
+// Short sets the short flag name.
+func (f *FlagClause) Short(name rune) *FlagClause {
+	f.shorthand = name
+	return f
+}
+
+// Bool makes this flag a boolean flag.
+func (f *FlagClause) Bool() (target *bool) {
+	target = new(bool)
+	f.SetValue(newBoolValue(target))
+	return
+}

vendor/gopkg.in/alecthomas/kingpin.v2/global.go

@@ -0,0 +1,94 @@
+package kingpin
+
+import (
+	"os"
+	"path/filepath"
+)
+
+var (
+	// CommandLine is the default Kingpin parser.
+	CommandLine = New(filepath.Base(os.Args[0]), "")
+	// Global help flag. Exposed for user customisation.
+	HelpFlag = CommandLine.HelpFlag
+	// Top-level help command. Exposed for user customisation. May be nil.
+	HelpCommand = CommandLine.HelpCommand
+	// Global version flag. Exposed for user customisation. May be nil.
+	VersionFlag = CommandLine.VersionFlag
+)
+
+// Command adds a new command to the default parser.
+func Command(name, help string) *CmdClause {
+	return CommandLine.Command(name, help)
+}
+
+// Flag adds a new flag to the default parser.
+func Flag(name, help string) *FlagClause {
+	return CommandLine.Flag(name, help)
+}
+
+// Arg adds a new argument to the top-level of the default parser.
+func Arg(name, help string) *ArgClause {
+	return CommandLine.Arg(name, help)
+}
+
+// Parse and return the selected command. Will call the termination handler if
+// an error is encountered.
+func Parse() string {
+	selected := MustParse(CommandLine.Parse(os.Args[1:]))
+	if selected == "" && CommandLine.cmdGroup.have() {
+		Usage()
+		CommandLine.terminate(0)
+	}
+	return selected
+}
+
+// Errorf prints an error message to stderr.
+func Errorf(format string, args ...interface{}) {
+	CommandLine.Errorf(format, args...)
+}
+
+// Fatalf prints an error message to stderr and exits.
+func Fatalf(format string, args ...interface{}) {
+	CommandLine.Fatalf(format, args...)
+}
+
+// FatalIfError prints an error and exits if err is not nil. The error is printed
+// with the given prefix.
+func FatalIfError(err error, format string, args ...interface{}) {
+	CommandLine.FatalIfError(err, format, args...)
+}
+
+// FatalUsage prints an error message followed by usage information, then
+// exits with a non-zero status.
+func FatalUsage(format string, args ...interface{}) {
+	CommandLine.FatalUsage(format, args...)
+}
+
+// FatalUsageContext writes a printf formatted error message to stderr, then
+// usage information for the given ParseContext, before exiting.
+func FatalUsageContext(context *ParseContext, format string, args ...interface{}) {
+	CommandLine.FatalUsageContext(context, format, args...)
+}
+
+// Usage prints usage to stderr.
+func Usage() {
+	CommandLine.Usage(os.Args[1:])
+}
+
+// Set global usage template to use (defaults to DefaultUsageTemplate).
+func UsageTemplate(template string) *Application {
+	return CommandLine.UsageTemplate(template)
+}
+
+// MustParse can be used with app.Parse(args) to exit with an error if parsing fails.
+func MustParse(command string, err error) string {
+	if err != nil {
+		Fatalf("%s, try --help", err)
+	}
+	return command
+}
+
+// Version adds a flag for displaying the application version number.
+func Version(version string) *Application {
+	return CommandLine.Version(version)
+}

vendor/gopkg.in/alecthomas/kingpin.v2/guesswidth.go

@@ -0,0 +1,9 @@
+// +build appengine !linux,!freebsd,!darwin,!dragonfly,!netbsd,!openbsd
+
+package kingpin
+
+import "io"
+
+func guessWidth(w io.Writer) int {
+	return 80
+}

vendor/gopkg.in/alecthomas/kingpin.v2/guesswidth_unix.go

@@ -0,0 +1,38 @@
+// +build !appengine,linux freebsd darwin dragonfly netbsd openbsd
+
+package kingpin
+
+import (
+	"io"
+	"os"
+	"strconv"
+	"syscall"
+	"unsafe"
+)
+
+func guessWidth(w io.Writer) int {
+	// check if COLUMNS env is set to comply with
+	// http://pubs.opengroup.org/onlinepubs/009604499/basedefs/xbd_chap08.html
+	colsStr := os.Getenv("COLUMNS")
+	if colsStr != "" {
+		if cols, err := strconv.Atoi(colsStr); err == nil {
+			return cols
+		}
+	}
+
+	if t, ok := w.(*os.File); ok {
+		fd := t.Fd()
+		var dimensions [4]uint16
+
+		if _, _, err := syscall.Syscall6(
+			syscall.SYS_IOCTL,
+			uintptr(fd),
+			uintptr(syscall.TIOCGWINSZ),
+			uintptr(unsafe.Pointer(&dimensions)),
+			0, 0, 0,
+		); err == 0 {
+			return int(dimensions[1])
+		}
+	}
+	return 80
+}

vendor/gopkg.in/alecthomas/kingpin.v2/model.go

@@ -0,0 +1,227 @@
+package kingpin
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Data model for Kingpin command-line structure.
+
+type FlagGroupModel struct {
+	Flags []*FlagModel
+}
+
+func (f *FlagGroupModel) FlagSummary() string {
+	out := []string{}
+	count := 0
+	for _, flag := range f.Flags {
+		if flag.Name != "help" {
+			count++
+		}
+		if flag.Required {
+			if flag.IsBoolFlag() {
+				out = append(out, fmt.Sprintf("--[no-]%s", flag.Name))
+			} else {
+				out = append(out, fmt.Sprintf("--%s=%s", flag.Name, flag.FormatPlaceHolder()))
+			}
+		}
+	}
+	if count != len(out) {
+		out = append(out, "[<flags>]")
+	}
+	return strings.Join(out, " ")
+}
+
+type FlagModel struct {
+	Name        string
+	Help        string
+	Short       rune
+	Default     []string
+	Envar       string
+	PlaceHolder string
+	Required    bool
+	Hidden      bool
+	Value       Value
+}
+
+func (f *FlagModel) String() string {
+	return f.Value.String()
+}
+
+func (f *FlagModel) IsBoolFlag() bool {
+	if fl, ok := f.Value.(boolFlag); ok {
+		return fl.IsBoolFlag()
+	}
+	return false
+}
+
+func (f *FlagModel) FormatPlaceHolder() string {
+	if f.PlaceHolder != "" {
+		return f.PlaceHolder
+	}
+	if len(f.Default) > 0 {
+		ellipsis := ""
+		if len(f.Default) > 1 {
+			ellipsis = "..."
+		}
+		if _, ok := f.Value.(*stringValue); ok {
+			return strconv.Quote(f.Default[0]) + ellipsis
+		}
+		return f.Default[0] + ellipsis
+	}
+	return strings.ToUpper(f.Name)
+}
+
+type ArgGroupModel struct {
+	Args []*ArgModel
+}
+
+func (a *ArgGroupModel) ArgSummary() string {
+	depth := 0
+	out := []string{}
+	for _, arg := range a.Args {
+		h := "<" + arg.Name + ">"
+		if !arg.Required {
+			h = "[" + h
+			depth++
+		}
+		out = append(out, h)
+	}
+	out[len(out)-1] = out[len(out)-1] + strings.Repeat("]", depth)
+	return strings.Join(out, " ")
+}
+
+type ArgModel struct {
+	Name     string
+	Help     string
+	Default  []string
+	Envar    string
+	Required bool
+	Value    Value
+}
+
+func (a *ArgModel) String() string {
+	return a.Value.String()
+}
+
+type CmdGroupModel struct {
+	Commands []*CmdModel
+}
+
+func (c *CmdGroupModel) FlattenedCommands() (out []*CmdModel) {
+	for _, cmd := range c.Commands {
+		if len(cmd.Commands) == 0 {
+			out = append(out, cmd)
+		}
+		out = append(out, cmd.FlattenedCommands()...)
+	}
+	return
+}
+
+type CmdModel struct {
+	Name        string
+	Aliases     []string
+	Help        string
+	FullCommand string
+	Depth       int
+	Hidden      bool
+	Default     bool
+	*FlagGroupModel
+	*ArgGroupModel
+	*CmdGroupModel
+}
+
+func (c *CmdModel) String() string {
+	return c.FullCommand
+}
+
+type ApplicationModel struct {
+	Name    string
+	Help    string
+	Version string
+	Author  string
+	*ArgGroupModel
+	*CmdGroupModel
+	*FlagGroupModel
+}
+
+func (a *Application) Model() *ApplicationModel {
+	return &ApplicationModel{
+		Name:           a.Name,
+		Help:           a.Help,
+		Version:        a.version,
+		Author:         a.author,
+		FlagGroupModel: a.flagGroup.Model(),
+		ArgGroupModel:  a.argGroup.Model(),
+		CmdGroupModel:  a.cmdGroup.Model(),
+	}
+}
+
+func (a *argGroup) Model() *ArgGroupModel {
+	m := &ArgGroupModel{}
+	for _, arg := range a.args {
+		m.Args = append(m.Args, arg.Model())
+	}
+	return m
+}
+
+func (a *ArgClause) Model() *ArgModel {
+	return &ArgModel{
+		Name:     a.name,
+		Help:     a.help,
+		Default:  a.defaultValues,
+		Envar:    a.envar,
+		Required: a.required,
+		Value:    a.value,
+	}
+}
+
+func (f *flagGroup) Model() *FlagGroupModel {
+	m := &FlagGroupModel{}
+	for _, fl := range f.flagOrder {
+		m.Flags = append(m.Flags, fl.Model())
+	}
+	return m
+}
+
+func (f *FlagClause) Model() *FlagModel {
+	return &FlagModel{
+		Name:        f.name,
+		Help:        f.help,
+		Short:       rune(f.shorthand),
+		Default:     f.defaultValues,
+		Envar:       f.envar,
+		PlaceHolder: f.placeholder,
+		Required:    f.required,
+		Hidden:      f.hidden,
+		Value:       f.value,
+	}
+}
+
+func (c *cmdGroup) Model() *CmdGroupModel {
+	m := &CmdGroupModel{}
+	for _, cm := range c.commandOrder {
+		m.Commands = append(m.Commands, cm.Model())
+	}
+	return m
+}
+
+func (c *CmdClause) Model() *CmdModel {
+	depth := 0
+	for i := c; i != nil; i = i.parent {
+		depth++
+	}
+	return &CmdModel{
+		Name:           c.name,
+		Aliases:        c.aliases,
+		Help:           c.help,
+		Depth:          depth,
+		Hidden:         c.hidden,
+		Default:        c.isDefault,
+		FullCommand:    c.FullCommand(),
+		FlagGroupModel: c.flagGroup.Model(),
+		ArgGroupModel:  c.argGroup.Model(),
+		CmdGroupModel:  c.cmdGroup.Model(),
+	}
+}

vendor/gopkg.in/alecthomas/kingpin.v2/parser.go

@@ -0,0 +1,382 @@
+package kingpin
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+	"unicode/utf8"
+)
+
+type TokenType int
+
+// Token types.
+const (
+	TokenShort TokenType = iota
+	TokenLong
+	TokenArg
+	TokenError
+	TokenEOL
+)
+
+func (t TokenType) String() string {
+	switch t {
+	case TokenShort:
+		return "short flag"
+	case TokenLong:
+		return "long flag"
+	case TokenArg:
+		return "argument"
+	case TokenError:
+		return "error"
+	case TokenEOL:
+		return "<EOL>"
+	}
+	return "?"
+}
+
+var (
+	TokenEOLMarker = Token{-1, TokenEOL, ""}
+)
+
+type Token struct {
+	Index int
+	Type  TokenType
+	Value string
+}
+
+func (t *Token) Equal(o *Token) bool {
+	return t.Index == o.Index
+}
+
+func (t *Token) IsFlag() bool {
+	return t.Type == TokenShort || t.Type == TokenLong
+}
+
+func (t *Token) IsEOF() bool {
+	return t.Type == TokenEOL
+}
+
+func (t *Token) String() string {
+	switch t.Type {
+	case TokenShort:
+		return "-" + t.Value
+	case TokenLong:
+		return "--" + t.Value
+	case TokenArg:
+		return t.Value
+	case TokenError:
+		return "error: " + t.Value
+	case TokenEOL:
+		return "<EOL>"
+	default:
+		panic("unhandled type")
+	}
+}
+
+// A union of possible elements in a parse stack.
+type ParseElement struct {
+	// Clause is either *CmdClause, *ArgClause or *FlagClause.
+	Clause interface{}
+	// Value is corresponding value for an ArgClause or FlagClause (if any).
+	Value *string
+}
+
+// ParseContext holds the current context of the parser. When passed to
+// Action() callbacks Elements will be fully populated with *FlagClause,
+// *ArgClause and *CmdClause values and their corresponding arguments (if
+// any).
+type ParseContext struct {
+	SelectedCommand *CmdClause
+	ignoreDefault   bool
+	argsOnly        bool
+	peek            []*Token
+	argi            int // Index of current command-line arg we're processing.
+	args            []string
+	rawArgs         []string
+	flags           *flagGroup
+	arguments       *argGroup
+	argumenti       int // Cursor into arguments
+	// Flags, arguments and commands encountered and collected during parse.
+	Elements []*ParseElement
+}
+
+func (p *ParseContext) nextArg() *ArgClause {
+	if p.argumenti >= len(p.arguments.args) {
+		return nil
+	}
+	arg := p.arguments.args[p.argumenti]
+	if !arg.consumesRemainder() {
+		p.argumenti++
+	}
+	return arg
+}
+
+func (p *ParseContext) next() {
+	p.argi++
+	p.args = p.args[1:]
+}
+
+// HasTrailingArgs returns true if there are unparsed command-line arguments.
+// This can occur if the parser can not match remaining arguments.
+func (p *ParseContext) HasTrailingArgs() bool {
+	return len(p.args) > 0
+}
+
+func tokenize(args []string, ignoreDefault bool) *ParseContext {
+	return &ParseContext{
+		ignoreDefault: ignoreDefault,
+		args:          args,
+		rawArgs:       args,
+		flags:         newFlagGroup(),
+		arguments:     newArgGroup(),
+	}
+}
+
+func (p *ParseContext) mergeFlags(flags *flagGroup) {
+	for _, flag := range flags.flagOrder {
+		if flag.shorthand != 0 {
+			p.flags.short[string(flag.shorthand)] = flag
+		}
+		p.flags.long[flag.name] = flag
+		p.flags.flagOrder = append(p.flags.flagOrder, flag)
+	}
+}
+
+func (p *ParseContext) mergeArgs(args *argGroup) {
+	for _, arg := range args.args {
+		p.arguments.args = append(p.arguments.args, arg)
+	}
+}
+
+func (p *ParseContext) EOL() bool {
+	return p.Peek().Type == TokenEOL
+}
+
+// Next token in the parse context.
+func (p *ParseContext) Next() *Token {
+	if len(p.peek) > 0 {
+		return p.pop()
+	}
+
+	// End of tokens.
+	if len(p.args) == 0 {
+		return &Token{Index: p.argi, Type: TokenEOL}
+	}
+
+	arg := p.args[0]
+	p.next()
+
+	if p.argsOnly {
+		return &Token{p.argi, TokenArg, arg}
+	}
+
+	// All remaining args are passed directly.
+	if arg == "--" {
+		p.argsOnly = true
+		return p.Next()
+	}
+
+	if strings.HasPrefix(arg, "--") {
+		parts := strings.SplitN(arg[2:], "=", 2)
+		token := &Token{p.argi, TokenLong, parts[0]}
+		if len(parts) == 2 {
+			p.Push(&Token{p.argi, TokenArg, parts[1]})
+		}
+		return token
+	}
+
+	if strings.HasPrefix(arg, "-") {
+		if len(arg) == 1 {
+			return &Token{Index: p.argi, Type: TokenShort}
+		}
+		shortRune, size := utf8.DecodeRuneInString(arg[1:])
+		short := string(shortRune)
+		flag, ok := p.flags.short[short]
+		// Not a known short flag, we'll just return it anyway.
+		if !ok {
+		} else if fb, ok := flag.value.(boolFlag); ok && fb.IsBoolFlag() {
+			// Bool short flag.
+		} else {
+			// Short flag with combined argument: -fARG
+			token := &Token{p.argi, TokenShort, short}
+			if len(arg) > size+1 {
+				p.Push(&Token{p.argi, TokenArg, arg[size+1:]})
+			}
+			return token
+		}
+
+		if len(arg) > size+1 {
+			p.args = append([]string{"-" + arg[size+1:]}, p.args...)
+		}
+		return &Token{p.argi, TokenShort, short}
+	} else if strings.HasPrefix(arg, "@") {
+		expanded, err := ExpandArgsFromFile(arg[1:])
+		if err != nil {
+			return &Token{p.argi, TokenError, err.Error()}
+		}
+		if len(p.args) == 0 {
+			p.args = expanded
+		} else {
+			p.args = append(expanded, p.args...)
+		}
+		return p.Next()
+	}
+
+	return &Token{p.argi, TokenArg, arg}
+}
+
+func (p *ParseContext) Peek() *Token {
+	if len(p.peek) == 0 {
+		return p.Push(p.Next())
+	}
+	return p.peek[len(p.peek)-1]
+}
+
+func (p *ParseContext) Push(token *Token) *Token {
+	p.peek = append(p.peek, token)
+	return token
+}
+
+func (p *ParseContext) pop() *Token {
+	end := len(p.peek) - 1
+	token := p.peek[end]
+	p.peek = p.peek[0:end]
+	return token
+}
+
+func (p *ParseContext) String() string {
+	return p.SelectedCommand.FullCommand()
+}
+
+func (p *ParseContext) matchedFlag(flag *FlagClause, value string) {
+	p.Elements = append(p.Elements, &ParseElement{Clause: flag, Value: &value})
+}
+
+func (p *ParseContext) matchedArg(arg *ArgClause, value string) {
+	p.Elements = append(p.Elements, &ParseElement{Clause: arg, Value: &value})
+}
+
+func (p *ParseContext) matchedCmd(cmd *CmdClause) {
+	p.Elements = append(p.Elements, &ParseElement{Clause: cmd})
+	p.mergeFlags(cmd.flagGroup)
+	p.mergeArgs(cmd.argGroup)
+	p.SelectedCommand = cmd
+}
+
+// Expand arguments from a file. Lines starting with # will be treated as comments.
+func ExpandArgsFromFile(filename string) (out []string, err error) {
+	r, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer r.Close()
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		out = append(out, line)
+	}
+	err = scanner.Err()
+	return
+}
+
+func parse(context *ParseContext, app *Application) (err error) {
+	context.mergeFlags(app.flagGroup)
+	context.mergeArgs(app.argGroup)
+
+	cmds := app.cmdGroup
+	ignoreDefault := context.ignoreDefault
+
+loop:
+	for !context.EOL() {
+		token := context.Peek()
+
+		switch token.Type {
+		case TokenLong, TokenShort:
+			if flag, err := context.flags.parse(context); err != nil {
+				if !ignoreDefault {
+					if cmd := cmds.defaultSubcommand(); cmd != nil {
+						cmd.completionAlts = cmds.cmdNames()
+						context.matchedCmd(cmd)
+						cmds = cmd.cmdGroup
+						break
+					}
+				}
+				return err
+			} else if flag == HelpFlag {
+				ignoreDefault = true
+			}
+
+		case TokenArg:
+			if cmds.have() {
+				selectedDefault := false
+				cmd, ok := cmds.commands[token.String()]
+				if !ok {
+					if !ignoreDefault {
+						if cmd = cmds.defaultSubcommand(); cmd != nil {
+							cmd.completionAlts = cmds.cmdNames()
+							selectedDefault = true
+						}
+					}
+					if cmd == nil {
+						return fmt.Errorf("expected command but got %q", token)
+					}
+				}
+				if cmd == HelpCommand {
+					ignoreDefault = true
+				}
+				cmd.completionAlts = nil
+				context.matchedCmd(cmd)
+				cmds = cmd.cmdGroup
+				if !selectedDefault {
+					context.Next()
+				}
+			} else if context.arguments.have() {
+				if app.noInterspersed {
+					// no more flags
+					context.argsOnly = true
+				}
+				arg := context.nextArg()
+				if arg == nil {
+					break loop
+				}
+				context.matchedArg(arg, token.String())
+				context.Next()
+			} else {
+				break loop
+			}
+
+		case TokenEOL:
+			break loop
+		}
+	}
+
+	// Move to innermost default command.
+	for !ignoreDefault {
+		if cmd := cmds.defaultSubcommand(); cmd != nil {
+			cmd.completionAlts = cmds.cmdNames()
+			context.matchedCmd(cmd)
+			cmds = cmd.cmdGroup
+		} else {
+			break
+		}
+	}
+
+	if !context.EOL() {
+		return fmt.Errorf("unexpected %s", context.Peek())
+	}
+
+	// Set defaults for all remaining args.
+	for arg := context.nextArg(); arg != nil && !arg.consumesRemainder(); arg = context.nextArg() {
+		for _, defaultValue := range arg.defaultValues {
+			if err := arg.value.Set(defaultValue); err != nil {
+				return fmt.Errorf("invalid default value '%s' for argument '%s'", defaultValue, arg.name)
+			}
+		}
+	}
+
+	return
+}

vendor/gopkg.in/alecthomas/kingpin.v2/parsers.go

@@ -0,0 +1,212 @@
+package kingpin
+
+import (
+	"net"
+	"net/url"
+	"os"
+	"time"
+
+	"github.com/alecthomas/units"
+)
+
+type Settings interface {
+	SetValue(value Value)
+}
+
+type parserMixin struct {
+	value    Value
+	required bool
+}
+
+func (p *parserMixin) SetValue(value Value) {
+	p.value = value
+}
+
+// StringMap provides key=value parsing into a map.
+func (p *parserMixin) StringMap() (target *map[string]string) {
+	target = &(map[string]string{})
+	p.StringMapVar(target)
+	return
+}
+
+// Duration sets the parser to a time.Duration parser.
+func (p *parserMixin) Duration() (target *time.Duration) {
+	target = new(time.Duration)
+	p.DurationVar(target)
+	return
+}
+
+// Bytes parses numeric byte units. eg. 1.5KB
+func (p *parserMixin) Bytes() (target *units.Base2Bytes) {
+	target = new(units.Base2Bytes)
+	p.BytesVar(target)
+	return
+}
+
+// IP sets the parser to a net.IP parser.
+func (p *parserMixin) IP() (target *net.IP) {
+	target = new(net.IP)
+	p.IPVar(target)
+	return
+}
+
+// TCP (host:port) address.
+func (p *parserMixin) TCP() (target **net.TCPAddr) {
+	target = new(*net.TCPAddr)
+	p.TCPVar(target)
+	return
+}
+
+// TCPVar (host:port) address.
+func (p *parserMixin) TCPVar(target **net.TCPAddr) {
+	p.SetValue(newTCPAddrValue(target))
+}
+
+// ExistingFile sets the parser to one that requires and returns an existing file.
+func (p *parserMixin) ExistingFile() (target *string) {
+	target = new(string)
+	p.ExistingFileVar(target)
+	return
+}
+
+// ExistingDir sets the parser to one that requires and returns an existing directory.
+func (p *parserMixin) ExistingDir() (target *string) {
+	target = new(string)
+	p.ExistingDirVar(target)
+	return
+}
+
+// ExistingFileOrDir sets the parser to one that requires and returns an existing file OR directory.
+func (p *parserMixin) ExistingFileOrDir() (target *string) {
+	target = new(string)
+	p.ExistingFileOrDirVar(target)
+	return
+}
+
+// File returns an os.File against an existing file.
+func (p *parserMixin) File() (target **os.File) {
+	target = new(*os.File)
+	p.FileVar(target)
+	return
+}
+
+// File attempts to open a File with os.OpenFile(flag, perm).
+func (p *parserMixin) OpenFile(flag int, perm os.FileMode) (target **os.File) {
+	target = new(*os.File)
+	p.OpenFileVar(target, flag, perm)
+	return
+}
+
+// URL provides a valid, parsed url.URL.
+func (p *parserMixin) URL() (target **url.URL) {
+	target = new(*url.URL)
+	p.URLVar(target)
+	return
+}
+
+// StringMap provides key=value parsing into a map.
+func (p *parserMixin) StringMapVar(target *map[string]string) {
+	p.SetValue(newStringMapValue(target))
+}
+
+// Float sets the parser to a float64 parser.
+func (p *parserMixin) Float() (target *float64) {
+	return p.Float64()
+}
+
+// Float sets the parser to a float64 parser.
+func (p *parserMixin) FloatVar(target *float64) {
+	p.Float64Var(target)
+}
+
+// Duration sets the parser to a time.Duration parser.
+func (p *parserMixin) DurationVar(target *time.Duration) {
+	p.SetValue(newDurationValue(target))
+}
+
+// BytesVar parses numeric byte units. eg. 1.5KB
+func (p *parserMixin) BytesVar(target *units.Base2Bytes) {
+	p.SetValue(newBytesValue(target))
+}
+
+// IP sets the parser to a net.IP parser.
+func (p *parserMixin) IPVar(target *net.IP) {
+	p.SetValue(newIPValue(target))
+}
+
+// ExistingFile sets the parser to one that requires and returns an existing file.
+func (p *parserMixin) ExistingFileVar(target *string) {
+	p.SetValue(newExistingFileValue(target))
+}
+
+// ExistingDir sets the parser to one that requires and returns an existing directory.
+func (p *parserMixin) ExistingDirVar(target *string) {
+	p.SetValue(newExistingDirValue(target))
+}
+
+// ExistingDir sets the parser to one that requires and returns an existing directory.
+func (p *parserMixin) ExistingFileOrDirVar(target *string) {
+	p.SetValue(newExistingFileOrDirValue(target))
+}
+
+// FileVar opens an existing file.
+func (p *parserMixin) FileVar(target **os.File) {
+	p.SetValue(newFileValue(target, os.O_RDONLY, 0))
+}
+
+// OpenFileVar calls os.OpenFile(flag, perm)
+func (p *parserMixin) OpenFileVar(target **os.File, flag int, perm os.FileMode) {
+	p.SetValue(newFileValue(target, flag, perm))
+}
+
+// URL provides a valid, parsed url.URL.
+func (p *parserMixin) URLVar(target **url.URL) {
+	p.SetValue(newURLValue(target))
+}
+
+// URLList provides a parsed list of url.URL values.
+func (p *parserMixin) URLList() (target *[]*url.URL) {
+	target = new([]*url.URL)
+	p.URLListVar(target)
+	return
+}
+
+// URLListVar provides a parsed list of url.URL values.
+func (p *parserMixin) URLListVar(target *[]*url.URL) {
+	p.SetValue(newURLListValue(target))
+}
+
+// Enum allows a value from a set of options.
+func (p *parserMixin) Enum(options ...string) (target *string) {
+	target = new(string)
+	p.EnumVar(target, options...)
+	return
+}
+
+// EnumVar allows a value from a set of options.
+func (p *parserMixin) EnumVar(target *string, options ...string) {
+	p.SetValue(newEnumFlag(target, options...))
+}
+
+// Enums allows a set of values from a set of options.
+func (p *parserMixin) Enums(options ...string) (target *[]string) {
+	target = new([]string)
+	p.EnumsVar(target, options...)
+	return
+}
+
+// EnumVar allows a value from a set of options.
+func (p *parserMixin) EnumsVar(target *[]string, options ...string) {
+	p.SetValue(newEnumsFlag(target, options...))
+}
+
+// A Counter increments a number each time it is encountered.
+func (p *parserMixin) Counter() (target *int) {
+	target = new(int)
+	p.CounterVar(target)
+	return
+}
+
+func (p *parserMixin) CounterVar(target *int) {
+	p.SetValue(newCounterValue(target))
+}