//
// Copyright (c) 2011-2019 Canonical Ltd
// Copyright (c) 2006-2010 Kirill Simonov
//
// 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.
package yaml
import (
"bytes"
)
// The parser implements the following grammar:
//
// stream ::= STREAM-START implicit_document? explicit_document* STREAM-END
// implicit_document ::= block_node DOCUMENT-END*
// explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
// block_node_or_indentless_sequence ::=
// ALIAS
// | properties (block_content | indentless_block_sequence)?
// | block_content
// | indentless_block_sequence
// block_node ::= ALIAS
// | properties block_content?
// | block_content
// flow_node ::= ALIAS
// | properties flow_content?
// | flow_content
// properties ::= TAG ANCHOR? | ANCHOR TAG?
// block_content ::= block_collection | flow_collection | SCALAR
// flow_content ::= flow_collection | SCALAR
// block_collection ::= block_sequence | block_mapping
// flow_collection ::= flow_sequence | flow_mapping
// block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
// indentless_sequence ::= (BLOCK-ENTRY block_node?)+
// block_mapping ::= BLOCK-MAPPING_START
// ((KEY block_node_or_indentless_sequence?)?
// (VALUE block_node_or_indentless_sequence?)?)*
// BLOCK-END
// flow_sequence ::= FLOW-SEQUENCE-START
// (flow_sequence_entry FLOW-ENTRY)*
// flow_sequence_entry?
// FLOW-SEQUENCE-END
// flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// flow_mapping ::= FLOW-MAPPING-START
// (flow_mapping_entry FLOW-ENTRY)*
// flow_mapping_entry?
// FLOW-MAPPING-END
// flow_mapping_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// Peek the next token in the token queue.
func peek_token(parser *yaml_parser_t) *yaml_token_t {
if parser.token_available || yaml_parser_fetch_more_tokens(parser) {
token := &parser.tokens[parser.tokens_head]
yaml_parser_unfold_comments(parser, token)
return token
}
return nil
}
// yaml_parser_unfold_comments walks through the comments queue and joins all
// comments behind the position of the provided token into the respective
// top-level comment slices in the parser.
func yaml_parser_unfold_comments(parser *yaml_parser_t, token *yaml_token_t) {
for parser.comments_head < len(parser.comments) && token.start_mark.index >= parser.comments[parser.comments_head].token_mark.index {
comment := &parser.comments[parser.comments_head]
if len(comment.head) > 0 {
if token.typ == yaml_BLOCK_END_TOKEN {
// No heads on ends, so keep comment.head for a follow up token.
break
}
if len(parser.head_comment) > 0 {
parser.head_comment = append(parser.head_comment, '\n')
}
parser.head_comment = append(parser.head_comment, comment.head...)
}
if len(comment.foot) > 0 {
if len(parser.foot_comment) > 0 {
parser.foot_comment = append(parser.foot_comment, '\n')
}
parser.foot_comment = append(parser.foot_comment, comment.foot...)
}
if len(comment.line) > 0 {
if len(parser.line_comment) > 0 {
parser.line_comment = append(parser.line_comment, '\n')
}
parser.line_comment = append(parser.line_comment, comment.line...)
}
*comment = yaml_comment_t{}
parser.comments_head++
}
}
// Remove the next token from the queue (must be called after peek_token).
func skip_token(parser *yaml_parser_t) {
parser.token_available = false
parser.tokens_parsed++
parser.stream_end_produced = parser.tokens[parser.tokens_head].typ == yaml_STREAM_END_TOKEN
parser.tokens_head++
}
// Get the next event.
func yaml_parser_parse(parser *yaml_parser_t, event *yaml_event_t) bool {
// Erase the event object.
*event = yaml_event_t{}
// No events after the end of the stream or error.
if parser.stream_end_produced || parser.error != yaml_NO_ERROR || parser.state == yaml_PARSE_END_STATE {
return true
}
// Generate the next event.
return yaml_parser_state_machine(parser, event)
}
// Set parser error.
func yaml_parser_set_parser_error(parser *yaml_parser_t, problem string, problem_mark yaml_mark_t) bool {
parser.error = yaml_PARSER_ERROR
parser.problem = problem
parser.problem_mark = problem_mark
return false
}
func yaml_parser_set_parser_error_context(parser *yaml_parser_t, context string, context_mark yaml_mark_t, problem string, problem_mark yaml_mark_t) bool {
parser.error = yaml_PARSER_ERROR
parser.context = context
parser.context_mark = context_mark
parser.problem = problem
parser.problem_mark = problem_mark
return false
}
// State dispatcher.
func yaml_parser_state_machine(parser *yaml_parser_t, event *yaml_event_t) bool {
//trace("yaml_parser_state_machine", "state:", parser.state.String())
switch parser.state {
case yaml_PARSE_STREAM_START_STATE:
return yaml_parser_parse_stream_start(parser, event)
case yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE:
return yaml_parser_parse_document_start(parser, event, true)
case yaml_PARSE_DOCUMENT_START_STATE:
return yaml_parser_parse_document_start(parser, event, false)
case yaml_PARSE_DOCUMENT_CONTENT_STATE:
return yaml_parser_parse_document_content(parser, event)
case yaml_PARSE_DOCUMENT_END_STATE:
return yaml_parser_parse_document_end(parser, event)
case yaml_PARSE_BLOCK_NODE_STATE:
return yaml_parser_parse_node(parser, event, true, false)
case yaml_PARSE_BLOCK_NODE_OR_INDENTLESS_SEQUENCE_STATE:
return yaml_parser_parse_node(parser, event, true, true)
case yaml_PARSE_FLOW_NODE_STATE:
return yaml_parser_parse_node(parser, event, false, false)
case yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE:
return yaml_parser_parse_block_sequence_entry(parser, event, true)
case yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE:
return yaml_parser_parse_block_sequence_entry(parser, event, false)
case yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE:
return yaml_parser_parse_indentless_sequence_entry(parser, event)
case yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE:
return yaml_parser_parse_block_mapping_key(parser, event, true)
case yaml_PARSE_BLOCK_MAPPING_KEY_STATE:
return yaml_parser_parse_block_mapping_key(parser, event, false)
case yaml_PARSE_BLOCK_MAPPING_VALUE_STATE:
return yaml_parser_parse_block_mapping_value(parser, event)
case yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE:
return yaml_parser_parse_flow_sequence_entry(parser, event, true)
case yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE:
return yaml_parser_parse_flow_sequence_entry(parser, event, false)
case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE:
return yaml_parser_parse_flow_sequence_entry_mapping_key(parser, event)
case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE:
return yaml_parser_parse_flow_sequence_entry_mapping_value(parser, event)
case yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE:
return yaml_parser_parse_flow_sequence_entry_mapping_end(parser, event)
case yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE:
return yaml_parser_parse_flow_mapping_key(parser, event, true)
case yaml_PARSE_FLOW_MAPPING_KEY_STATE:
return yaml_parser_parse_flow_mapping_key(parser, event, false)
case yaml_PARSE_FLOW_MAPPING_VALUE_STATE:
return yaml_parser_parse_flow_mapping_value(parser, event, false)
case yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE:
return yaml_parser_parse_flow_mapping_value(parser, event, true)
default:
panic("invalid parser state")
}
}
// Parse the production:
// stream ::= STREAM-START implicit_document? explicit_document* STREAM-END
// ************
func yaml_parser_parse_stream_start(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_STREAM_START_TOKEN {
return yaml_parser_set_parser_error(parser, "did not find expected <stream-start>", token.start_mark)
}
parser.state = yaml_PARSE_IMPLICIT_DOCUMENT_START_STATE
*event = yaml_event_t{
typ: yaml_STREAM_START_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
encoding: token.encoding,
}
skip_token(parser)
return true
}
// Parse the productions:
// implicit_document ::= block_node DOCUMENT-END*
// *
// explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
// *************************
func yaml_parser_parse_document_start(parser *yaml_parser_t, event *yaml_event_t, implicit bool) bool {
token := peek_token(parser)
if token == nil {
return false
}
// Parse extra document end indicators.
if !implicit {
for token.typ == yaml_DOCUMENT_END_TOKEN {
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
}
}
if implicit && token.typ != yaml_VERSION_DIRECTIVE_TOKEN &&
token.typ != yaml_TAG_DIRECTIVE_TOKEN &&
token.typ != yaml_DOCUMENT_START_TOKEN &&
token.typ != yaml_STREAM_END_TOKEN {
// Parse an implicit document.
if !yaml_parser_process_directives(parser, nil, nil) {
return false
}
parser.states = append(parser.states, yaml_PARSE_DOCUMENT_END_STATE)
parser.state = yaml_PARSE_BLOCK_NODE_STATE
var head_comment []byte
if len(parser.head_comment) > 0 {
// [Go] Scan the header comment backwards, and if an empty line is found, break
// the header so the part before the last empty line goes into the
// document header, while the bottom of it goes into a follow up event.
for i := len(parser.head_comment) - 1; i > 0; i-- {
if parser.head_comment[i] == '\n' {
if i == len(parser.head_comment)-1 {
head_comment = parser.head_comment[:i]
parser.head_comment = parser.head_comment[i+1:]
break
} else if parser.head_comment[i-1] == '\n' {
head_comment = parser.head_comment[:i-1]
parser.head_comment = parser.head_comment[i+1:]
break
}
}
}
}
*event = yaml_event_t{
typ: yaml_DOCUMENT_START_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
head_comment: head_comment,
}
} else if token.typ != yaml_STREAM_END_TOKEN {
// Parse an explicit document.
var version_directive *yaml_version_directive_t
var tag_directives []yaml_tag_directive_t
start_mark := token.start_mark
if !yaml_parser_process_directives(parser, &version_directive, &tag_directives) {
return false
}
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_DOCUMENT_START_TOKEN {
yaml_parser_set_parser_error(parser,
"did not find expected <document start>", token.start_mark)
return false
}
parser.states = append(parser.states, yaml_PARSE_DOCUMENT_END_STATE)
parser.state = yaml_PARSE_DOCUMENT_CONTENT_STATE
end_mark := token.end_mark
*event = yaml_event_t{
typ: yaml_DOCUMENT_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
version_directive: version_directive,
tag_directives: tag_directives,
implicit: false,
}
skip_token(parser)
} else {
// Parse the stream end.
parser.state = yaml_PARSE_END_STATE
*event = yaml_event_t{
typ: yaml_STREAM_END_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
}
skip_token(parser)
}
return true
}
// Parse the productions:
// explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
// ***********
//
func yaml_parser_parse_document_content(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_VERSION_DIRECTIVE_TOKEN ||
token.typ == yaml_TAG_DIRECTIVE_TOKEN ||
token.typ == yaml_DOCUMENT_START_TOKEN ||
token.typ == yaml_DOCUMENT_END_TOKEN ||
token.typ == yaml_STREAM_END_TOKEN {
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
return yaml_parser_process_empty_scalar(parser, event,
token.start_mark)
}
return yaml_parser_parse_node(parser, event, true, false)
}
// Parse the productions:
// implicit_document ::= block_node DOCUMENT-END*
// *************
// explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
//
func yaml_parser_parse_document_end(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
start_mark := token.start_mark
end_mark := token.start_mark
implicit := true
if token.typ == yaml_DOCUMENT_END_TOKEN {
end_mark = token.end_mark
skip_token(parser)
implicit = false
}
parser.tag_directives = parser.tag_directives[:0]
parser.state = yaml_PARSE_DOCUMENT_START_STATE
*event = yaml_event_t{
typ: yaml_DOCUMENT_END_EVENT,
start_mark: start_mark,
end_mark: end_mark,
implicit: implicit,
}
yaml_parser_set_event_comments(parser, event)
if len(event.head_comment) > 0 && len(event.foot_comment) == 0 {
event.foot_comment = event.head_comment
event.head_comment = nil
}
return true
}
func yaml_parser_set_event_comments(parser *yaml_parser_t, event *yaml_event_t) {
event.head_comment = parser.head_comment
event.line_comment = parser.line_comment
event.foot_comment = parser.foot_comment
parser.head_comment = nil
parser.line_comment = nil
parser.foot_comment = nil
parser.tail_comment = nil
parser.stem_comment = nil
}
// Parse the productions:
// block_node_or_indentless_sequence ::=
// ALIAS
// *****
// | properties (block_content | indentless_block_sequence)?
// ********** *
// | block_content | indentless_block_sequence
// *
// block_node ::= ALIAS
// *****
// | properties block_content?
// ********** *
// | block_content
// *
// flow_node ::= ALIAS
// *****
// | properties flow_content?
// ********** *
// | flow_content
// *
// properties ::= TAG ANCHOR? | ANCHOR TAG?
// *************************
// block_content ::= block_collection | flow_collection | SCALAR
// ******
// flow_content ::= flow_collection | SCALAR
// ******
func yaml_parser_parse_node(parser *yaml_parser_t, event *yaml_event_t, block, indentless_sequence bool) bool {
//defer trace("yaml_parser_parse_node", "block:", block, "indentless_sequence:", indentless_sequence)()
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_ALIAS_TOKEN {
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
*event = yaml_event_t{
typ: yaml_ALIAS_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
anchor: token.value,
}
yaml_parser_set_event_comments(parser, event)
skip_token(parser)
return true
}
start_mark := token.start_mark
end_mark := token.start_mark
var tag_token bool
var tag_handle, tag_suffix, anchor []byte
var tag_mark yaml_mark_t
if token.typ == yaml_ANCHOR_TOKEN {
anchor = token.value
start_mark = token.start_mark
end_mark = token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_TAG_TOKEN {
tag_token = true
tag_handle = token.value
tag_suffix = token.suffix
tag_mark = token.start_mark
end_mark = token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
}
} else if token.typ == yaml_TAG_TOKEN {
tag_token = true
tag_handle = token.value
tag_suffix = token.suffix
start_mark = token.start_mark
tag_mark = token.start_mark
end_mark = token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_ANCHOR_TOKEN {
anchor = token.value
end_mark = token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
}
}
var tag []byte
if tag_token {
if len(tag_handle) == 0 {
tag = tag_suffix
tag_suffix = nil
} else {
for i := range parser.tag_directives {
if bytes.Equal(parser.tag_directives[i].handle, tag_handle) {
tag = append([]byte(nil), parser.tag_directives[i].prefix...)
tag = append(tag, tag_suffix...)
break
}
}
if len(tag) == 0 {
yaml_parser_set_parser_error_context(parser,
"while parsing a node", start_mark,
"found undefined tag handle", tag_mark)
return false
}
}
}
implicit := len(tag) == 0
if indentless_sequence && token.typ == yaml_BLOCK_ENTRY_TOKEN {
end_mark = token.end_mark
parser.state = yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE
*event = yaml_event_t{
typ: yaml_SEQUENCE_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
style: yaml_style_t(yaml_BLOCK_SEQUENCE_STYLE),
}
return true
}
if token.typ == yaml_SCALAR_TOKEN {
var plain_implicit, quoted_implicit bool
end_mark = token.end_mark
if (len(tag) == 0 && token.style == yaml_PLAIN_SCALAR_STYLE) || (len(tag) == 1 && tag[0] == '!') {
plain_implicit = true
} else if len(tag) == 0 {
quoted_implicit = true
}
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
*event = yaml_event_t{
typ: yaml_SCALAR_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
value: token.value,
implicit: plain_implicit,
quoted_implicit: quoted_implicit,
style: yaml_style_t(token.style),
}
yaml_parser_set_event_comments(parser, event)
skip_token(parser)
return true
}
if token.typ == yaml_FLOW_SEQUENCE_START_TOKEN {
// [Go] Some of the events below can be merged as they differ only on style.
end_mark = token.end_mark
parser.state = yaml_PARSE_FLOW_SEQUENCE_FIRST_ENTRY_STATE
*event = yaml_event_t{
typ: yaml_SEQUENCE_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
style: yaml_style_t(yaml_FLOW_SEQUENCE_STYLE),
}
yaml_parser_set_event_comments(parser, event)
return true
}
if token.typ == yaml_FLOW_MAPPING_START_TOKEN {
end_mark = token.end_mark
parser.state = yaml_PARSE_FLOW_MAPPING_FIRST_KEY_STATE
*event = yaml_event_t{
typ: yaml_MAPPING_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
style: yaml_style_t(yaml_FLOW_MAPPING_STYLE),
}
yaml_parser_set_event_comments(parser, event)
return true
}
if block && token.typ == yaml_BLOCK_SEQUENCE_START_TOKEN {
end_mark = token.end_mark
parser.state = yaml_PARSE_BLOCK_SEQUENCE_FIRST_ENTRY_STATE
*event = yaml_event_t{
typ: yaml_SEQUENCE_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
style: yaml_style_t(yaml_BLOCK_SEQUENCE_STYLE),
}
if parser.stem_comment != nil {
event.head_comment = parser.stem_comment
parser.stem_comment = nil
}
return true
}
if block && token.typ == yaml_BLOCK_MAPPING_START_TOKEN {
end_mark = token.end_mark
parser.state = yaml_PARSE_BLOCK_MAPPING_FIRST_KEY_STATE
*event = yaml_event_t{
typ: yaml_MAPPING_START_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
style: yaml_style_t(yaml_BLOCK_MAPPING_STYLE),
}
if parser.stem_comment != nil {
event.head_comment = parser.stem_comment
parser.stem_comment = nil
}
return true
}
if len(anchor) > 0 || len(tag) > 0 {
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
*event = yaml_event_t{
typ: yaml_SCALAR_EVENT,
start_mark: start_mark,
end_mark: end_mark,
anchor: anchor,
tag: tag,
implicit: implicit,
quoted_implicit: false,
style: yaml_style_t(yaml_PLAIN_SCALAR_STYLE),
}
return true
}
context := "while parsing a flow node"
if block {
context = "while parsing a block node"
}
yaml_parser_set_parser_error_context(parser, context, start_mark,
"did not find expected node content", token.start_mark)
return false
}
// Parse the productions:
// block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
// ******************** *********** * *********
//
func yaml_parser_parse_block_sequence_entry(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
if first {
token := peek_token(parser)
if token == nil {
return false
}
parser.marks = append(parser.marks, token.start_mark)
skip_token(parser)
}
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_BLOCK_ENTRY_TOKEN {
mark := token.end_mark
prior_head_len := len(parser.head_comment)
skip_token(parser)
yaml_parser_split_stem_comment(parser, prior_head_len)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_BLOCK_ENTRY_TOKEN && token.typ != yaml_BLOCK_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE)
return yaml_parser_parse_node(parser, event, true, false)
} else {
parser.state = yaml_PARSE_BLOCK_SEQUENCE_ENTRY_STATE
return yaml_parser_process_empty_scalar(parser, event, mark)
}
}
if token.typ == yaml_BLOCK_END_TOKEN {
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
*event = yaml_event_t{
typ: yaml_SEQUENCE_END_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
}
skip_token(parser)
return true
}
context_mark := parser.marks[len(parser.marks)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
return yaml_parser_set_parser_error_context(parser,
"while parsing a block collection", context_mark,
"did not find expected '-' indicator", token.start_mark)
}
// Parse the productions:
// indentless_sequence ::= (BLOCK-ENTRY block_node?)+
// *********** *
func yaml_parser_parse_indentless_sequence_entry(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_BLOCK_ENTRY_TOKEN {
mark := token.end_mark
prior_head_len := len(parser.head_comment)
skip_token(parser)
yaml_parser_split_stem_comment(parser, prior_head_len)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_BLOCK_ENTRY_TOKEN &&
token.typ != yaml_KEY_TOKEN &&
token.typ != yaml_VALUE_TOKEN &&
token.typ != yaml_BLOCK_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE)
return yaml_parser_parse_node(parser, event, true, false)
}
parser.state = yaml_PARSE_INDENTLESS_SEQUENCE_ENTRY_STATE
return yaml_parser_process_empty_scalar(parser, event, mark)
}
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
*event = yaml_event_t{
typ: yaml_SEQUENCE_END_EVENT,
start_mark: token.start_mark,
end_mark: token.start_mark, // [Go] Shouldn't this be token.end_mark?
}
return true
}
// Split stem comment from head comment.
//
// When a sequence or map is found under a sequence entry, the former head comment
// is assigned to the underlying sequence or map as a whole, not the individual
// sequence or map entry as would be expected otherwise. To handle this case the
// previous head comment is moved aside as the stem comment.
func yaml_parser_split_stem_comment(parser *yaml_parser_t, stem_len int) {
if stem_len == 0 {
return
}
token := peek_token(parser)
if token == nil || token.typ != yaml_BLOCK_SEQUENCE_START_TOKEN && token.typ != yaml_BLOCK_MAPPING_START_TOKEN {
return
}
parser.stem_comment = parser.head_comment[:stem_len]
if len(parser.head_comment) == stem_len {
parser.head_comment = nil
} else {
// Copy suffix to prevent very strange bugs if someone ever appends
// further bytes to the prefix in the stem_comment slice above.
parser.head_comment = append([]byte(nil), parser.head_comment[stem_len+1:]...)
}
}
// Parse the productions:
// block_mapping ::= BLOCK-MAPPING_START
// *******************
// ((KEY block_node_or_indentless_sequence?)?
// *** *
// (VALUE block_node_or_indentless_sequence?)?)*
//
// BLOCK-END
// *********
//
func yaml_parser_parse_block_mapping_key(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
if first {
token := peek_token(parser)
if token == nil {
return false
}
parser.marks = append(parser.marks, token.start_mark)
skip_token(parser)
}
token := peek_token(parser)
if token == nil {
return false
}
// [Go] A tail comment was left from the prior mapping value processed. Emit an event
// as it needs to be processed with that value and not the following key.
if len(parser.tail_comment) > 0 {
*event = yaml_event_t{
typ: yaml_TAIL_COMMENT_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
foot_comment: parser.tail_comment,
}
parser.tail_comment = nil
return true
}
if token.typ == yaml_KEY_TOKEN {
mark := token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_KEY_TOKEN &&
token.typ != yaml_VALUE_TOKEN &&
token.typ != yaml_BLOCK_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_BLOCK_MAPPING_VALUE_STATE)
return yaml_parser_parse_node(parser, event, true, true)
} else {
parser.state = yaml_PARSE_BLOCK_MAPPING_VALUE_STATE
return yaml_parser_process_empty_scalar(parser, event, mark)
}
} else if token.typ == yaml_BLOCK_END_TOKEN {
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
*event = yaml_event_t{
typ: yaml_MAPPING_END_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
}
yaml_parser_set_event_comments(parser, event)
skip_token(parser)
return true
}
context_mark := parser.marks[len(parser.marks)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
return yaml_parser_set_parser_error_context(parser,
"while parsing a block mapping", context_mark,
"did not find expected key", token.start_mark)
}
// Parse the productions:
// block_mapping ::= BLOCK-MAPPING_START
//
// ((KEY block_node_or_indentless_sequence?)?
//
// (VALUE block_node_or_indentless_sequence?)?)*
// ***** *
// BLOCK-END
//
//
func yaml_parser_parse_block_mapping_value(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_VALUE_TOKEN {
mark := token.end_mark
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_KEY_TOKEN &&
token.typ != yaml_VALUE_TOKEN &&
token.typ != yaml_BLOCK_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_BLOCK_MAPPING_KEY_STATE)
return yaml_parser_parse_node(parser, event, true, true)
}
parser.state = yaml_PARSE_BLOCK_MAPPING_KEY_STATE
return yaml_parser_process_empty_scalar(parser, event, mark)
}
parser.state = yaml_PARSE_BLOCK_MAPPING_KEY_STATE
return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
}
// Parse the productions:
// flow_sequence ::= FLOW-SEQUENCE-START
// *******************
// (flow_sequence_entry FLOW-ENTRY)*
// * **********
// flow_sequence_entry?
// *
// FLOW-SEQUENCE-END
// *****************
// flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// *
//
func yaml_parser_parse_flow_sequence_entry(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
if first {
token := peek_token(parser)
if token == nil {
return false
}
parser.marks = append(parser.marks, token.start_mark)
skip_token(parser)
}
token := peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
if !first {
if token.typ == yaml_FLOW_ENTRY_TOKEN {
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
} else {
context_mark := parser.marks[len(parser.marks)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
return yaml_parser_set_parser_error_context(parser,
"while parsing a flow sequence", context_mark,
"did not find expected ',' or ']'", token.start_mark)
}
}
if token.typ == yaml_KEY_TOKEN {
parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_KEY_STATE
*event = yaml_event_t{
typ: yaml_MAPPING_START_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
implicit: true,
style: yaml_style_t(yaml_FLOW_MAPPING_STYLE),
}
skip_token(parser)
return true
} else if token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE)
return yaml_parser_parse_node(parser, event, false, false)
}
}
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
*event = yaml_event_t{
typ: yaml_SEQUENCE_END_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
}
yaml_parser_set_event_comments(parser, event)
skip_token(parser)
return true
}
//
// Parse the productions:
// flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// *** *
//
func yaml_parser_parse_flow_sequence_entry_mapping_key(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_VALUE_TOKEN &&
token.typ != yaml_FLOW_ENTRY_TOKEN &&
token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE)
return yaml_parser_parse_node(parser, event, false, false)
}
mark := token.end_mark
skip_token(parser)
parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_VALUE_STATE
return yaml_parser_process_empty_scalar(parser, event, mark)
}
// Parse the productions:
// flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// ***** *
//
func yaml_parser_parse_flow_sequence_entry_mapping_value(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
if token.typ == yaml_VALUE_TOKEN {
skip_token(parser)
token := peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_FLOW_ENTRY_TOKEN && token.typ != yaml_FLOW_SEQUENCE_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE)
return yaml_parser_parse_node(parser, event, false, false)
}
}
parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_MAPPING_END_STATE
return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
}
// Parse the productions:
// flow_sequence_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// *
//
func yaml_parser_parse_flow_sequence_entry_mapping_end(parser *yaml_parser_t, event *yaml_event_t) bool {
token := peek_token(parser)
if token == nil {
return false
}
parser.state = yaml_PARSE_FLOW_SEQUENCE_ENTRY_STATE
*event = yaml_event_t{
typ: yaml_MAPPING_END_EVENT,
start_mark: token.start_mark,
end_mark: token.start_mark, // [Go] Shouldn't this be end_mark?
}
return true
}
// Parse the productions:
// flow_mapping ::= FLOW-MAPPING-START
// ******************
// (flow_mapping_entry FLOW-ENTRY)*
// * **********
// flow_mapping_entry?
// ******************
// FLOW-MAPPING-END
// ****************
// flow_mapping_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// * *** *
//
func yaml_parser_parse_flow_mapping_key(parser *yaml_parser_t, event *yaml_event_t, first bool) bool {
if first {
token := peek_token(parser)
parser.marks = append(parser.marks, token.start_mark)
skip_token(parser)
}
token := peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_FLOW_MAPPING_END_TOKEN {
if !first {
if token.typ == yaml_FLOW_ENTRY_TOKEN {
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
} else {
context_mark := parser.marks[len(parser.marks)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
return yaml_parser_set_parser_error_context(parser,
"while parsing a flow mapping", context_mark,
"did not find expected ',' or '}'", token.start_mark)
}
}
if token.typ == yaml_KEY_TOKEN {
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_VALUE_TOKEN &&
token.typ != yaml_FLOW_ENTRY_TOKEN &&
token.typ != yaml_FLOW_MAPPING_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_VALUE_STATE)
return yaml_parser_parse_node(parser, event, false, false)
} else {
parser.state = yaml_PARSE_FLOW_MAPPING_VALUE_STATE
return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
}
} else if token.typ != yaml_FLOW_MAPPING_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_EMPTY_VALUE_STATE)
return yaml_parser_parse_node(parser, event, false, false)
}
}
parser.state = parser.states[len(parser.states)-1]
parser.states = parser.states[:len(parser.states)-1]
parser.marks = parser.marks[:len(parser.marks)-1]
*event = yaml_event_t{
typ: yaml_MAPPING_END_EVENT,
start_mark: token.start_mark,
end_mark: token.end_mark,
}
yaml_parser_set_event_comments(parser, event)
skip_token(parser)
return true
}
// Parse the productions:
// flow_mapping_entry ::= flow_node | KEY flow_node? (VALUE flow_node?)?
// * ***** *
//
func yaml_parser_parse_flow_mapping_value(parser *yaml_parser_t, event *yaml_event_t, empty bool) bool {
token := peek_token(parser)
if token == nil {
return false
}
if empty {
parser.state = yaml_PARSE_FLOW_MAPPING_KEY_STATE
return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
}
if token.typ == yaml_VALUE_TOKEN {
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
if token.typ != yaml_FLOW_ENTRY_TOKEN && token.typ != yaml_FLOW_MAPPING_END_TOKEN {
parser.states = append(parser.states, yaml_PARSE_FLOW_MAPPING_KEY_STATE)
return yaml_parser_parse_node(parser, event, false, false)
}
}
parser.state = yaml_PARSE_FLOW_MAPPING_KEY_STATE
return yaml_parser_process_empty_scalar(parser, event, token.start_mark)
}
// Generate an empty scalar event.
func yaml_parser_process_empty_scalar(parser *yaml_parser_t, event *yaml_event_t, mark yaml_mark_t) bool {
*event = yaml_event_t{
typ: yaml_SCALAR_EVENT,
start_mark: mark,
end_mark: mark,
value: nil, // Empty
implicit: true,
style: yaml_style_t(yaml_PLAIN_SCALAR_STYLE),
}
return true
}
var default_tag_directives = []yaml_tag_directive_t{
{[]byte("!"), []byte("!")},
{[]byte("!!"), []byte("tag:yaml.org,2002:")},
}
// Parse directives.
func yaml_parser_process_directives(parser *yaml_parser_t,
version_directive_ref **yaml_version_directive_t,
tag_directives_ref *[]yaml_tag_directive_t) bool {
var version_directive *yaml_version_directive_t
var tag_directives []yaml_tag_directive_t
token := peek_token(parser)
if token == nil {
return false
}
for token.typ == yaml_VERSION_DIRECTIVE_TOKEN || token.typ == yaml_TAG_DIRECTIVE_TOKEN {
if token.typ == yaml_VERSION_DIRECTIVE_TOKEN {
if version_directive != nil {
yaml_parser_set_parser_error(parser,
"found duplicate %YAML directive", token.start_mark)
return false
}
if token.major != 1 || token.minor != 1 {
yaml_parser_set_parser_error(parser,
"found incompatible YAML document", token.start_mark)
return false
}
version_directive = &yaml_version_directive_t{
major: token.major,
minor: token.minor,
}
} else if token.typ == yaml_TAG_DIRECTIVE_TOKEN {
value := yaml_tag_directive_t{
handle: token.value,
prefix: token.prefix,
}
if !yaml_parser_append_tag_directive(parser, value, false, token.start_mark) {
return false
}
tag_directives = append(tag_directives, value)
}
skip_token(parser)
token = peek_token(parser)
if token == nil {
return false
}
}
for i := range default_tag_directives {
if !yaml_parser_append_tag_directive(parser, default_tag_directives[i], true, token.start_mark) {
return false
}
}
if version_directive_ref != nil {
*version_directive_ref = version_directive
}
if tag_directives_ref != nil {
*tag_directives_ref = tag_directives
}
return true
}
// Append a tag directive to the directives stack.
func yaml_parser_append_tag_directive(parser *yaml_parser_t, value yaml_tag_directive_t, allow_duplicates bool, mark yaml_mark_t) bool {
for i := range parser.tag_directives {
if bytes.Equal(value.handle, parser.tag_directives[i].handle) {
if allow_duplicates {
return true
}
return yaml_parser_set_parser_error(parser, "found duplicate %TAG directive", mark)
}
}
// [Go] I suspect the copy is unnecessary. This was likely done
// because there was no way to track ownership of the data.
value_copy := yaml_tag_directive_t{
handle: make([]byte, len(value.handle)),
prefix: make([]byte, len(value.prefix)),
}
copy(value_copy.handle, value.handle)
copy(value_copy.prefix, value.prefix)
parser.tag_directives = append(parser.tag_directives, value_copy)
return true
}