gotosocial/vendor/github.com/godbus/dbus/v5/dbus.go

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package dbus
import (
"errors"
"fmt"
"reflect"
"strings"
)
var (
byteType = reflect.TypeOf(byte(0))
boolType = reflect.TypeOf(false)
uint8Type = reflect.TypeOf(uint8(0))
int16Type = reflect.TypeOf(int16(0))
uint16Type = reflect.TypeOf(uint16(0))
intType = reflect.TypeOf(int(0))
uintType = reflect.TypeOf(uint(0))
int32Type = reflect.TypeOf(int32(0))
uint32Type = reflect.TypeOf(uint32(0))
int64Type = reflect.TypeOf(int64(0))
uint64Type = reflect.TypeOf(uint64(0))
float64Type = reflect.TypeOf(float64(0))
stringType = reflect.TypeOf("")
signatureType = reflect.TypeOf(Signature{""})
objectPathType = reflect.TypeOf(ObjectPath(""))
variantType = reflect.TypeOf(Variant{Signature{""}, nil})
interfacesType = reflect.TypeOf([]interface{}{})
interfaceType = reflect.TypeOf((*interface{})(nil)).Elem()
unixFDType = reflect.TypeOf(UnixFD(0))
unixFDIndexType = reflect.TypeOf(UnixFDIndex(0))
errType = reflect.TypeOf((*error)(nil)).Elem()
)
// An InvalidTypeError signals that a value which cannot be represented in the
// D-Bus wire format was passed to a function.
type InvalidTypeError struct {
Type reflect.Type
}
func (e InvalidTypeError) Error() string {
return "dbus: invalid type " + e.Type.String()
}
// Store copies the values contained in src to dest, which must be a slice of
// pointers. It converts slices of interfaces from src to corresponding structs
// in dest. An error is returned if the lengths of src and dest or the types of
// their elements don't match.
func Store(src []interface{}, dest ...interface{}) error {
if len(src) != len(dest) {
return errors.New("dbus.Store: length mismatch")
}
for i := range src {
if err := storeInterfaces(src[i], dest[i]); err != nil {
return err
}
}
return nil
}
func storeInterfaces(src, dest interface{}) error {
return store(reflect.ValueOf(dest), reflect.ValueOf(src))
}
func store(dest, src reflect.Value) error {
if dest.Kind() == reflect.Ptr {
if dest.IsNil() {
dest.Set(reflect.New(dest.Type().Elem()))
}
return store(dest.Elem(), src)
}
switch src.Kind() {
case reflect.Slice:
return storeSlice(dest, src)
case reflect.Map:
return storeMap(dest, src)
default:
return storeBase(dest, src)
}
}
func storeBase(dest, src reflect.Value) error {
return setDest(dest, src)
}
func setDest(dest, src reflect.Value) error {
if !isVariant(src.Type()) && isVariant(dest.Type()) {
//special conversion for dbus.Variant
dest.Set(reflect.ValueOf(MakeVariant(src.Interface())))
return nil
}
if isVariant(src.Type()) && !isVariant(dest.Type()) {
src = getVariantValue(src)
return store(dest, src)
}
if !src.Type().ConvertibleTo(dest.Type()) {
return fmt.Errorf(
"dbus.Store: type mismatch: cannot convert %s to %s",
src.Type(), dest.Type())
}
dest.Set(src.Convert(dest.Type()))
return nil
}
func kindsAreCompatible(dest, src reflect.Type) bool {
switch {
case isVariant(dest):
return true
case dest.Kind() == reflect.Interface:
return true
default:
return dest.Kind() == src.Kind()
}
}
func isConvertibleTo(dest, src reflect.Type) bool {
switch {
case isVariant(dest):
return true
case dest.Kind() == reflect.Interface:
return true
case dest.Kind() == reflect.Slice:
return src.Kind() == reflect.Slice &&
isConvertibleTo(dest.Elem(), src.Elem())
case dest.Kind() == reflect.Struct:
return src == interfacesType
default:
return src.ConvertibleTo(dest)
}
}
func storeMap(dest, src reflect.Value) error {
switch {
case !kindsAreCompatible(dest.Type(), src.Type()):
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"map: cannot store a value of %s into %s",
src.Type(), dest.Type())
case isVariant(dest.Type()):
return storeMapIntoVariant(dest, src)
case dest.Kind() == reflect.Interface:
return storeMapIntoInterface(dest, src)
case isConvertibleTo(dest.Type().Key(), src.Type().Key()) &&
isConvertibleTo(dest.Type().Elem(), src.Type().Elem()):
return storeMapIntoMap(dest, src)
default:
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"map: cannot convert a value of %s into %s",
src.Type(), dest.Type())
}
}
func storeMapIntoVariant(dest, src reflect.Value) error {
dv := reflect.MakeMap(src.Type())
err := store(dv, src)
if err != nil {
return err
}
return storeBase(dest, dv)
}
func storeMapIntoInterface(dest, src reflect.Value) error {
var dv reflect.Value
if isVariant(src.Type().Elem()) {
//Convert variants to interface{} recursively when converting
//to interface{}
dv = reflect.MakeMap(
reflect.MapOf(src.Type().Key(), interfaceType))
} else {
dv = reflect.MakeMap(src.Type())
}
err := store(dv, src)
if err != nil {
return err
}
return storeBase(dest, dv)
}
func storeMapIntoMap(dest, src reflect.Value) error {
if dest.IsNil() {
dest.Set(reflect.MakeMap(dest.Type()))
}
keys := src.MapKeys()
for _, key := range keys {
dkey := key.Convert(dest.Type().Key())
dval := reflect.New(dest.Type().Elem()).Elem()
err := store(dval, getVariantValue(src.MapIndex(key)))
if err != nil {
return err
}
dest.SetMapIndex(dkey, dval)
}
return nil
}
func storeSlice(dest, src reflect.Value) error {
switch {
case src.Type() == interfacesType && dest.Kind() == reflect.Struct:
//The decoder always decodes structs as slices of interface{}
return storeStruct(dest, src)
case !kindsAreCompatible(dest.Type(), src.Type()):
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"slice: cannot store a value of %s into %s",
src.Type(), dest.Type())
case isVariant(dest.Type()):
return storeSliceIntoVariant(dest, src)
case dest.Kind() == reflect.Interface:
return storeSliceIntoInterface(dest, src)
case isConvertibleTo(dest.Type().Elem(), src.Type().Elem()):
return storeSliceIntoSlice(dest, src)
default:
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"slice: cannot convert a value of %s into %s",
src.Type(), dest.Type())
}
}
func storeStruct(dest, src reflect.Value) error {
if isVariant(dest.Type()) {
return storeBase(dest, src)
}
dval := make([]interface{}, 0, dest.NumField())
dtype := dest.Type()
for i := 0; i < dest.NumField(); i++ {
field := dest.Field(i)
ftype := dtype.Field(i)
if ftype.PkgPath != "" {
continue
}
if ftype.Tag.Get("dbus") == "-" {
continue
}
dval = append(dval, field.Addr().Interface())
}
if src.Len() != len(dval) {
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"destination struct does not have "+
"enough fields need: %d have: %d",
src.Len(), len(dval))
}
return Store(src.Interface().([]interface{}), dval...)
}
func storeSliceIntoVariant(dest, src reflect.Value) error {
dv := reflect.MakeSlice(src.Type(), src.Len(), src.Cap())
err := store(dv, src)
if err != nil {
return err
}
return storeBase(dest, dv)
}
func storeSliceIntoInterface(dest, src reflect.Value) error {
var dv reflect.Value
if isVariant(src.Type().Elem()) {
//Convert variants to interface{} recursively when converting
//to interface{}
dv = reflect.MakeSlice(reflect.SliceOf(interfaceType),
src.Len(), src.Cap())
} else {
dv = reflect.MakeSlice(src.Type(), src.Len(), src.Cap())
}
err := store(dv, src)
if err != nil {
return err
}
return storeBase(dest, dv)
}
func storeSliceIntoSlice(dest, src reflect.Value) error {
if dest.IsNil() || dest.Len() < src.Len() {
dest.Set(reflect.MakeSlice(dest.Type(), src.Len(), src.Cap()))
}
if dest.Len() != src.Len() {
return fmt.Errorf(
"dbus.Store: type mismatch: "+
"slices are different lengths "+
"need: %d have: %d",
src.Len(), dest.Len())
}
for i := 0; i < src.Len(); i++ {
err := store(dest.Index(i), getVariantValue(src.Index(i)))
if err != nil {
return err
}
}
return nil
}
func getVariantValue(in reflect.Value) reflect.Value {
if isVariant(in.Type()) {
return reflect.ValueOf(in.Interface().(Variant).Value())
}
return in
}
func isVariant(t reflect.Type) bool {
return t == variantType
}
// An ObjectPath is an object path as defined by the D-Bus spec.
type ObjectPath string
// IsValid returns whether the object path is valid.
func (o ObjectPath) IsValid() bool {
s := string(o)
if len(s) == 0 {
return false
}
if s[0] != '/' {
return false
}
if s[len(s)-1] == '/' && len(s) != 1 {
return false
}
// probably not used, but technically possible
if s == "/" {
return true
}
split := strings.Split(s[1:], "/")
for _, v := range split {
if len(v) == 0 {
return false
}
for _, c := range v {
if !isMemberChar(c) {
return false
}
}
}
return true
}
// A UnixFD is a Unix file descriptor sent over the wire. See the package-level
// documentation for more information about Unix file descriptor passsing.
type UnixFD int32
// A UnixFDIndex is the representation of a Unix file descriptor in a message.
type UnixFDIndex uint32
// alignment returns the alignment of values of type t.
func alignment(t reflect.Type) int {
switch t {
case variantType:
return 1
case objectPathType:
return 4
case signatureType:
return 1
case interfacesType:
return 4
}
switch t.Kind() {
case reflect.Uint8:
return 1
case reflect.Uint16, reflect.Int16:
return 2
case reflect.Uint, reflect.Int, reflect.Uint32, reflect.Int32, reflect.String, reflect.Array, reflect.Slice, reflect.Map:
return 4
case reflect.Uint64, reflect.Int64, reflect.Float64, reflect.Struct:
return 8
case reflect.Ptr:
return alignment(t.Elem())
}
return 1
}
// isKeyType returns whether t is a valid type for a D-Bus dict.
func isKeyType(t reflect.Type) bool {
switch t.Kind() {
case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
reflect.Int16, reflect.Int32, reflect.Int64, reflect.Float64,
reflect.String, reflect.Uint, reflect.Int:
return true
}
return false
}
// isValidInterface returns whether s is a valid name for an interface.
func isValidInterface(s string) bool {
if len(s) == 0 || len(s) > 255 || s[0] == '.' {
return false
}
elem := strings.Split(s, ".")
if len(elem) < 2 {
return false
}
for _, v := range elem {
if len(v) == 0 {
return false
}
if v[0] >= '0' && v[0] <= '9' {
return false
}
for _, c := range v {
if !isMemberChar(c) {
return false
}
}
}
return true
}
// isValidMember returns whether s is a valid name for a member.
func isValidMember(s string) bool {
if len(s) == 0 || len(s) > 255 {
return false
}
i := strings.Index(s, ".")
if i != -1 {
return false
}
if s[0] >= '0' && s[0] <= '9' {
return false
}
for _, c := range s {
if !isMemberChar(c) {
return false
}
}
return true
}
func isMemberChar(c rune) bool {
return (c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') ||
(c >= 'a' && c <= 'z') || c == '_'
}