gotosocial/vendor/github.com/leodido/go-urn/machine.go.rl

386 lines
9.5 KiB
Ragel

package urn
import (
"fmt"
scimschema "github.com/leodido/go-urn/scim/schema"
)
var (
errPrefix = "expecting the prefix to be the \"urn\" string (whatever case) [col %d]"
errIdentifier = "expecting the identifier to be string (1..31 alnum chars, also containing dashes but not at its beginning) [col %d]"
errSpecificString = "expecting the specific string to be a string containing alnum, hex, or others ([()+,-.:=@;$_!*']) chars [col %d]"
errNoUrnWithinID = "expecting the identifier to not contain the \"urn\" reserved string [col %d]"
errHex = "expecting the percent encoded chars to be well-formed (%%alnum{2}) [col %d]"
errSCIMNamespace = "expecing the SCIM namespace identifier (ietf:params:scim) [col %d]"
errSCIMType = "expecting a correct SCIM type (schemas, api, param) [col %d]"
errSCIMName = "expecting one or more alnum char in the SCIM name part [col %d]"
errSCIMOther = "expecting a well-formed other SCIM part [col %d]"
errSCIMOtherIncomplete = "expecting a not empty SCIM other part after colon [col %d]"
err8141InformalID = "informal URN namespace must be in the form urn-[1-9][0-9] [col %d]"
err8141SpecificString = "expecting the specific string to contain alnum, hex, or others ([~&()+,-.:=@;$_!*'] or [/?] not in first position) chars [col %d]"
err8141Identifier = "expecting the indentifier to be a string with (length 2 to 32 chars) containing alnum (or dashes) not starting or ending with a dash [col %d]"
err8141RComponentStart = "expecting only one r-component (starting with the ?+ sequence) [col %d]"
err8141QComponentStart = "expecting only one q-component (starting with the ?= sequence) [col %d]"
err8141MalformedRComp = "expecting a non-empty r-component containing alnum, hex, or others ([~&()+,-.:=@;$_!*'] or [/?] but not at its beginning) [col %d]"
err8141MalformedQComp = "expecting a non-empty q-component containing alnum, hex, or others ([~&()+,-.:=@;$_!*'] or [/?] but not at its beginning) [col %d]"
)
%%{
machine urn;
# unsigned alphabet
alphtype uint8;
action mark {
m.pb = m.p
}
action tolower {
// List of positions in the buffer to later lowercase
output.tolower = append(output.tolower, m.p - m.pb)
}
action set_pre {
output.prefix = string(m.text())
}
action throw_pre_urn_err {
if m.parsingMode != RFC8141Only {
// Throw an error when:
// - we are entering here matching the the prefix in the namespace identifier part
// - looking ahead (3 chars) we find a colon
if pos := m.p + 3; pos < m.pe && m.data[pos] == 58 && output.prefix != "" {
m.err = fmt.Errorf(errNoUrnWithinID, pos)
fhold;
fgoto fail;
}
}
}
action set_nid {
output.ID = string(m.text())
}
action set_nss {
output.SS = string(m.text())
// Iterate upper letters lowering them
for _, i := range output.tolower {
m.data[m.pb+i] = m.data[m.pb+i] + 32
}
output.norm = string(m.text())
// Revert the buffer to the original
for _, i := range output.tolower {
m.data[m.pb+i] = m.data[m.pb+i] - 32
}
}
action err_pre {
m.err = fmt.Errorf(errPrefix, m.p)
fhold;
fgoto fail;
}
action err_nid {
m.err = fmt.Errorf(errIdentifier, m.p)
fhold;
fgoto fail;
}
action err_nss {
m.err = fmt.Errorf(errSpecificString, m.p)
fhold;
fgoto fail;
}
action err_urn {
m.err = fmt.Errorf(errNoUrnWithinID, m.p)
fhold;
fgoto fail;
}
action err_hex {
if m.parsingMode == RFC2141Only || m.parsingMode == RFC8141Only {
m.err = fmt.Errorf(errHex, m.p)
fhold;
fgoto fail;
}
}
action base_type {
output.kind = RFC2141;
}
pre = ([uU] @err(err_pre) [rR] @err(err_pre) [nN] @err(err_pre)) >mark >throw_pre_urn_err %set_pre;
nid = (alnum >mark (alnum | '-'){0,31}) $err(err_nid) %set_nid;
hex = '%' (digit | lower | upper >tolower){2} $err(err_hex);
sss = (alnum | [()+,\-.:=@;$_!*']);
nss = (sss | hex)+ $err(err_nss);
nid_not_urn = (nid - pre %err(err_urn));
urn = pre ':' @err(err_pre) (nid_not_urn ':' nss >mark %set_nss) %eof(base_type);
### SCIM BEG
action err_scim_nid {
m.err = fmt.Errorf(errSCIMNamespace, m.p)
fhold;
fgoto fail;
}
action err_scim_type {
m.err = fmt.Errorf(errSCIMType, m.p)
fhold;
fgoto fail;
}
action err_scim_name {
m.err = fmt.Errorf(errSCIMName, m.p)
fhold;
fgoto fail;
}
action err_scim_other {
if m.p == m.pe {
m.err = fmt.Errorf(errSCIMOtherIncomplete, m.p-1)
} else {
m.err = fmt.Errorf(errSCIMOther, m.p)
}
fhold;
fgoto fail;
}
action scim_type {
output.kind = RFC7643;
}
action create_scim {
output.scim = &SCIM{};
}
action set_scim_type {
output.scim.Type = scimschema.TypeFromString(string(m.text()))
}
action mark_scim_name {
output.scim.pos = m.p
}
action set_scim_name {
output.scim.Name = string(m.data[output.scim.pos:m.p])
}
action mark_scim_other {
output.scim.pos = m.p
}
action set_scim_other {
output.scim.Other = string(m.data[output.scim.pos:m.p])
}
scim_nid = 'ietf:params:scim' >mark %set_nid %create_scim $err(err_scim_nid);
scim_other = ':' (sss | hex)+ >mark_scim_other %set_scim_other $err(err_scim_other);
scim_name = (alnum)+ >mark_scim_name %set_scim_name $err(err_scim_name);
scim_type = ('schemas' | 'api' | 'param') >mark %set_scim_type $err(err_scim_type);
scim_only := pre ':' @err(err_pre) (scim_nid ':' scim_type ':' scim_name scim_other? %set_nss) %eof(scim_type);
### SCIM END
### 8141 BEG
action err_nss_8141 {
m.err = fmt.Errorf(err8141SpecificString, m.p)
fhold;
fgoto fail;
}
action err_nid_8141 {
m.err = fmt.Errorf(err8141Identifier, m.p)
fhold;
fgoto fail;
}
action rfc8141_type {
output.kind = RFC8141;
}
action set_r_component {
output.rComponent = string(m.text())
}
action set_q_component {
output.qComponent = string(m.text())
}
action set_f_component {
output.fComponent = string(m.text())
}
action informal_nid_match {
fhold;
m.err = fmt.Errorf(err8141InformalID, m.p);
fgoto fail;
}
action mark_r_start {
if output.rStart {
m.err = fmt.Errorf(err8141RComponentStart, m.p)
fhold;
fgoto fail;
}
output.rStart = true
}
action mark_q_start {
if output.qStart {
m.err = fmt.Errorf(err8141QComponentStart, m.p)
fhold;
fgoto fail;
}
output.qStart = true
}
action err_malformed_r_component {
m.err = fmt.Errorf(err8141MalformedRComp, m.p)
fhold;
fgoto fail;
}
action err_malformed_q_component {
m.err = fmt.Errorf(err8141MalformedQComp, m.p)
fhold;
fgoto fail;
}
pchar = (sss | '~' | '&' | hex);
component = pchar (pchar | '/' | '?')*;
r_start = ('?+') %mark_r_start;
r_component = r_start <: (r_start | component)+ $err(err_malformed_r_component) >mark %set_r_component;
q_start = ('?=') %mark_q_start;
q_component = q_start <: (q_start | component)+ $err(err_malformed_q_component) >mark %set_q_component;
rq_components = (r_component :>> q_component? | q_component);
fragment = (pchar | '/' | '?')*;
f_component = '#' fragment >mark %set_f_component;
nss_rfc8141 = (pchar >mark (pchar | '/')*) $err(err_nss_8141) %set_nss;
nid_rfc8141 = (alnum >mark (alnum | '-'){0,30} alnum) $err(err_nid_8141) %set_nid;
informal_id = pre ('-' [a-zA-z0] %to(informal_nid_match));
nid_rfc8141_not_urn = (nid_rfc8141 - informal_id?);
rfc8141_only := pre ':' @err(err_pre) nid_rfc8141_not_urn ':' nss_rfc8141 rq_components? f_component? %eof(rfc8141_type);
### 8141 END
fail := (any - [\n\r])* @err{ fgoto main; };
main := urn;
}%%
%% write data noerror noprefix;
// Machine is the interface representing the FSM
type Machine interface {
Error() error
Parse(input []byte) (*URN, error)
WithParsingMode(ParsingMode)
}
type machine struct {
data []byte
cs int
p, pe, eof, pb int
err error
startParsingAt int
parsingMode ParsingMode
parsingModeSet bool
}
// NewMachine creates a new FSM able to parse RFC 2141 strings.
func NewMachine(options ...Option) Machine {
m := &machine{
parsingModeSet: false,
}
for _, o := range options {
o(m)
}
// Set default parsing mode
if !m.parsingModeSet {
m.WithParsingMode(DefaultParsingMode)
}
%% access m.;
%% variable p m.p;
%% variable pe m.pe;
%% variable eof m.eof;
%% variable data m.data;
return m
}
// Err returns the error that occurred on the last call to Parse.
//
// If the result is nil, then the line was parsed successfully.
func (m *machine) Error() error {
return m.err
}
func (m *machine) text() []byte {
return m.data[m.pb:m.p]
}
// Parse parses the input byte array as a RFC 2141 or RFC7643 string.
func (m *machine) Parse(input []byte) (*URN, error) {
m.data = input
m.p = 0
m.pb = 0
m.pe = len(input)
m.eof = len(input)
m.err = nil
m.cs = m.startParsingAt
output := &URN{
tolower: []int{},
}
%% write exec;
if m.cs < first_final || m.cs == en_fail {
return nil, m.err
}
return output, nil
}
func (m *machine) WithParsingMode(x ParsingMode) {
m.parsingMode = x
switch m.parsingMode {
case RFC2141Only:
m.startParsingAt = en_main
case RFC8141Only:
m.startParsingAt = en_rfc8141_only
case RFC7643Only:
m.startParsingAt = en_scim_only
}
m.parsingModeSet = true
}