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khenaidood948f772021-08-11 17:49:24 -04001//
2// Copyright (c) 2011-2019 Canonical Ltd
3// Copyright (c) 2006-2010 Kirill Simonov
4//
5// Permission is hereby granted, free of charge, to any person obtaining a copy of
6// this software and associated documentation files (the "Software"), to deal in
7// the Software without restriction, including without limitation the rights to
8// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
9// of the Software, and to permit persons to whom the Software is furnished to do
10// so, subject to the following conditions:
11//
12// The above copyright notice and this permission notice shall be included in all
13// copies or substantial portions of the Software.
14//
15// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21// SOFTWARE.
22
23package yaml
24
25import (
26 "io"
27)
28
29func yaml_insert_token(parser *yaml_parser_t, pos int, token *yaml_token_t) {
30 //fmt.Println("yaml_insert_token", "pos:", pos, "typ:", token.typ, "head:", parser.tokens_head, "len:", len(parser.tokens))
31
32 // Check if we can move the queue at the beginning of the buffer.
33 if parser.tokens_head > 0 && len(parser.tokens) == cap(parser.tokens) {
34 if parser.tokens_head != len(parser.tokens) {
35 copy(parser.tokens, parser.tokens[parser.tokens_head:])
36 }
37 parser.tokens = parser.tokens[:len(parser.tokens)-parser.tokens_head]
38 parser.tokens_head = 0
39 }
40 parser.tokens = append(parser.tokens, *token)
41 if pos < 0 {
42 return
43 }
44 copy(parser.tokens[parser.tokens_head+pos+1:], parser.tokens[parser.tokens_head+pos:])
45 parser.tokens[parser.tokens_head+pos] = *token
46}
47
48// Create a new parser object.
49func yaml_parser_initialize(parser *yaml_parser_t) bool {
50 *parser = yaml_parser_t{
51 raw_buffer: make([]byte, 0, input_raw_buffer_size),
52 buffer: make([]byte, 0, input_buffer_size),
53 }
54 return true
55}
56
57// Destroy a parser object.
58func yaml_parser_delete(parser *yaml_parser_t) {
59 *parser = yaml_parser_t{}
60}
61
62// String read handler.
63func yaml_string_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
64 if parser.input_pos == len(parser.input) {
65 return 0, io.EOF
66 }
67 n = copy(buffer, parser.input[parser.input_pos:])
68 parser.input_pos += n
69 return n, nil
70}
71
72// Reader read handler.
73func yaml_reader_read_handler(parser *yaml_parser_t, buffer []byte) (n int, err error) {
74 return parser.input_reader.Read(buffer)
75}
76
77// Set a string input.
78func yaml_parser_set_input_string(parser *yaml_parser_t, input []byte) {
79 if parser.read_handler != nil {
80 panic("must set the input source only once")
81 }
82 parser.read_handler = yaml_string_read_handler
83 parser.input = input
84 parser.input_pos = 0
85}
86
87// Set a file input.
88func yaml_parser_set_input_reader(parser *yaml_parser_t, r io.Reader) {
89 if parser.read_handler != nil {
90 panic("must set the input source only once")
91 }
92 parser.read_handler = yaml_reader_read_handler
93 parser.input_reader = r
94}
95
96// Set the source encoding.
97func yaml_parser_set_encoding(parser *yaml_parser_t, encoding yaml_encoding_t) {
98 if parser.encoding != yaml_ANY_ENCODING {
99 panic("must set the encoding only once")
100 }
101 parser.encoding = encoding
102}
103
104// Create a new emitter object.
105func yaml_emitter_initialize(emitter *yaml_emitter_t) {
106 *emitter = yaml_emitter_t{
107 buffer: make([]byte, output_buffer_size),
108 raw_buffer: make([]byte, 0, output_raw_buffer_size),
109 states: make([]yaml_emitter_state_t, 0, initial_stack_size),
110 events: make([]yaml_event_t, 0, initial_queue_size),
111 best_width: -1,
112 }
113}
114
115// Destroy an emitter object.
116func yaml_emitter_delete(emitter *yaml_emitter_t) {
117 *emitter = yaml_emitter_t{}
118}
119
120// String write handler.
121func yaml_string_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
122 *emitter.output_buffer = append(*emitter.output_buffer, buffer...)
123 return nil
124}
125
126// yaml_writer_write_handler uses emitter.output_writer to write the
127// emitted text.
128func yaml_writer_write_handler(emitter *yaml_emitter_t, buffer []byte) error {
129 _, err := emitter.output_writer.Write(buffer)
130 return err
131}
132
133// Set a string output.
134func yaml_emitter_set_output_string(emitter *yaml_emitter_t, output_buffer *[]byte) {
135 if emitter.write_handler != nil {
136 panic("must set the output target only once")
137 }
138 emitter.write_handler = yaml_string_write_handler
139 emitter.output_buffer = output_buffer
140}
141
142// Set a file output.
143func yaml_emitter_set_output_writer(emitter *yaml_emitter_t, w io.Writer) {
144 if emitter.write_handler != nil {
145 panic("must set the output target only once")
146 }
147 emitter.write_handler = yaml_writer_write_handler
148 emitter.output_writer = w
149}
150
151// Set the output encoding.
152func yaml_emitter_set_encoding(emitter *yaml_emitter_t, encoding yaml_encoding_t) {
153 if emitter.encoding != yaml_ANY_ENCODING {
154 panic("must set the output encoding only once")
155 }
156 emitter.encoding = encoding
157}
158
159// Set the canonical output style.
160func yaml_emitter_set_canonical(emitter *yaml_emitter_t, canonical bool) {
161 emitter.canonical = canonical
162}
163
164// Set the indentation increment.
165func yaml_emitter_set_indent(emitter *yaml_emitter_t, indent int) {
166 if indent < 2 || indent > 9 {
167 indent = 2
168 }
169 emitter.best_indent = indent
170}
171
172// Set the preferred line width.
173func yaml_emitter_set_width(emitter *yaml_emitter_t, width int) {
174 if width < 0 {
175 width = -1
176 }
177 emitter.best_width = width
178}
179
180// Set if unescaped non-ASCII characters are allowed.
181func yaml_emitter_set_unicode(emitter *yaml_emitter_t, unicode bool) {
182 emitter.unicode = unicode
183}
184
185// Set the preferred line break character.
186func yaml_emitter_set_break(emitter *yaml_emitter_t, line_break yaml_break_t) {
187 emitter.line_break = line_break
188}
189
190///*
191// * Destroy a token object.
192// */
193//
194//YAML_DECLARE(void)
195//yaml_token_delete(yaml_token_t *token)
196//{
197// assert(token); // Non-NULL token object expected.
198//
199// switch (token.type)
200// {
201// case YAML_TAG_DIRECTIVE_TOKEN:
202// yaml_free(token.data.tag_directive.handle);
203// yaml_free(token.data.tag_directive.prefix);
204// break;
205//
206// case YAML_ALIAS_TOKEN:
207// yaml_free(token.data.alias.value);
208// break;
209//
210// case YAML_ANCHOR_TOKEN:
211// yaml_free(token.data.anchor.value);
212// break;
213//
214// case YAML_TAG_TOKEN:
215// yaml_free(token.data.tag.handle);
216// yaml_free(token.data.tag.suffix);
217// break;
218//
219// case YAML_SCALAR_TOKEN:
220// yaml_free(token.data.scalar.value);
221// break;
222//
223// default:
224// break;
225// }
226//
227// memset(token, 0, sizeof(yaml_token_t));
228//}
229//
230///*
231// * Check if a string is a valid UTF-8 sequence.
232// *
233// * Check 'reader.c' for more details on UTF-8 encoding.
234// */
235//
236//static int
237//yaml_check_utf8(yaml_char_t *start, size_t length)
238//{
239// yaml_char_t *end = start+length;
240// yaml_char_t *pointer = start;
241//
242// while (pointer < end) {
243// unsigned char octet;
244// unsigned int width;
245// unsigned int value;
246// size_t k;
247//
248// octet = pointer[0];
249// width = (octet & 0x80) == 0x00 ? 1 :
250// (octet & 0xE0) == 0xC0 ? 2 :
251// (octet & 0xF0) == 0xE0 ? 3 :
252// (octet & 0xF8) == 0xF0 ? 4 : 0;
253// value = (octet & 0x80) == 0x00 ? octet & 0x7F :
254// (octet & 0xE0) == 0xC0 ? octet & 0x1F :
255// (octet & 0xF0) == 0xE0 ? octet & 0x0F :
256// (octet & 0xF8) == 0xF0 ? octet & 0x07 : 0;
257// if (!width) return 0;
258// if (pointer+width > end) return 0;
259// for (k = 1; k < width; k ++) {
260// octet = pointer[k];
261// if ((octet & 0xC0) != 0x80) return 0;
262// value = (value << 6) + (octet & 0x3F);
263// }
264// if (!((width == 1) ||
265// (width == 2 && value >= 0x80) ||
266// (width == 3 && value >= 0x800) ||
267// (width == 4 && value >= 0x10000))) return 0;
268//
269// pointer += width;
270// }
271//
272// return 1;
273//}
274//
275
276// Create STREAM-START.
277func yaml_stream_start_event_initialize(event *yaml_event_t, encoding yaml_encoding_t) {
278 *event = yaml_event_t{
279 typ: yaml_STREAM_START_EVENT,
280 encoding: encoding,
281 }
282}
283
284// Create STREAM-END.
285func yaml_stream_end_event_initialize(event *yaml_event_t) {
286 *event = yaml_event_t{
287 typ: yaml_STREAM_END_EVENT,
288 }
289}
290
291// Create DOCUMENT-START.
292func yaml_document_start_event_initialize(
293 event *yaml_event_t,
294 version_directive *yaml_version_directive_t,
295 tag_directives []yaml_tag_directive_t,
296 implicit bool,
297) {
298 *event = yaml_event_t{
299 typ: yaml_DOCUMENT_START_EVENT,
300 version_directive: version_directive,
301 tag_directives: tag_directives,
302 implicit: implicit,
303 }
304}
305
306// Create DOCUMENT-END.
307func yaml_document_end_event_initialize(event *yaml_event_t, implicit bool) {
308 *event = yaml_event_t{
309 typ: yaml_DOCUMENT_END_EVENT,
310 implicit: implicit,
311 }
312}
313
314// Create ALIAS.
315func yaml_alias_event_initialize(event *yaml_event_t, anchor []byte) bool {
316 *event = yaml_event_t{
317 typ: yaml_ALIAS_EVENT,
318 anchor: anchor,
319 }
320 return true
321}
322
323// Create SCALAR.
324func yaml_scalar_event_initialize(event *yaml_event_t, anchor, tag, value []byte, plain_implicit, quoted_implicit bool, style yaml_scalar_style_t) bool {
325 *event = yaml_event_t{
326 typ: yaml_SCALAR_EVENT,
327 anchor: anchor,
328 tag: tag,
329 value: value,
330 implicit: plain_implicit,
331 quoted_implicit: quoted_implicit,
332 style: yaml_style_t(style),
333 }
334 return true
335}
336
337// Create SEQUENCE-START.
338func yaml_sequence_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_sequence_style_t) bool {
339 *event = yaml_event_t{
340 typ: yaml_SEQUENCE_START_EVENT,
341 anchor: anchor,
342 tag: tag,
343 implicit: implicit,
344 style: yaml_style_t(style),
345 }
346 return true
347}
348
349// Create SEQUENCE-END.
350func yaml_sequence_end_event_initialize(event *yaml_event_t) bool {
351 *event = yaml_event_t{
352 typ: yaml_SEQUENCE_END_EVENT,
353 }
354 return true
355}
356
357// Create MAPPING-START.
358func yaml_mapping_start_event_initialize(event *yaml_event_t, anchor, tag []byte, implicit bool, style yaml_mapping_style_t) {
359 *event = yaml_event_t{
360 typ: yaml_MAPPING_START_EVENT,
361 anchor: anchor,
362 tag: tag,
363 implicit: implicit,
364 style: yaml_style_t(style),
365 }
366}
367
368// Create MAPPING-END.
369func yaml_mapping_end_event_initialize(event *yaml_event_t) {
370 *event = yaml_event_t{
371 typ: yaml_MAPPING_END_EVENT,
372 }
373}
374
375// Destroy an event object.
376func yaml_event_delete(event *yaml_event_t) {
377 *event = yaml_event_t{}
378}
379
380///*
381// * Create a document object.
382// */
383//
384//YAML_DECLARE(int)
385//yaml_document_initialize(document *yaml_document_t,
386// version_directive *yaml_version_directive_t,
387// tag_directives_start *yaml_tag_directive_t,
388// tag_directives_end *yaml_tag_directive_t,
389// start_implicit int, end_implicit int)
390//{
391// struct {
392// error yaml_error_type_t
393// } context
394// struct {
395// start *yaml_node_t
396// end *yaml_node_t
397// top *yaml_node_t
398// } nodes = { NULL, NULL, NULL }
399// version_directive_copy *yaml_version_directive_t = NULL
400// struct {
401// start *yaml_tag_directive_t
402// end *yaml_tag_directive_t
403// top *yaml_tag_directive_t
404// } tag_directives_copy = { NULL, NULL, NULL }
405// value yaml_tag_directive_t = { NULL, NULL }
406// mark yaml_mark_t = { 0, 0, 0 }
407//
408// assert(document) // Non-NULL document object is expected.
409// assert((tag_directives_start && tag_directives_end) ||
410// (tag_directives_start == tag_directives_end))
411// // Valid tag directives are expected.
412//
413// if (!STACK_INIT(&context, nodes, INITIAL_STACK_SIZE)) goto error
414//
415// if (version_directive) {
416// version_directive_copy = yaml_malloc(sizeof(yaml_version_directive_t))
417// if (!version_directive_copy) goto error
418// version_directive_copy.major = version_directive.major
419// version_directive_copy.minor = version_directive.minor
420// }
421//
422// if (tag_directives_start != tag_directives_end) {
423// tag_directive *yaml_tag_directive_t
424// if (!STACK_INIT(&context, tag_directives_copy, INITIAL_STACK_SIZE))
425// goto error
426// for (tag_directive = tag_directives_start
427// tag_directive != tag_directives_end; tag_directive ++) {
428// assert(tag_directive.handle)
429// assert(tag_directive.prefix)
430// if (!yaml_check_utf8(tag_directive.handle,
431// strlen((char *)tag_directive.handle)))
432// goto error
433// if (!yaml_check_utf8(tag_directive.prefix,
434// strlen((char *)tag_directive.prefix)))
435// goto error
436// value.handle = yaml_strdup(tag_directive.handle)
437// value.prefix = yaml_strdup(tag_directive.prefix)
438// if (!value.handle || !value.prefix) goto error
439// if (!PUSH(&context, tag_directives_copy, value))
440// goto error
441// value.handle = NULL
442// value.prefix = NULL
443// }
444// }
445//
446// DOCUMENT_INIT(*document, nodes.start, nodes.end, version_directive_copy,
447// tag_directives_copy.start, tag_directives_copy.top,
448// start_implicit, end_implicit, mark, mark)
449//
450// return 1
451//
452//error:
453// STACK_DEL(&context, nodes)
454// yaml_free(version_directive_copy)
455// while (!STACK_EMPTY(&context, tag_directives_copy)) {
456// value yaml_tag_directive_t = POP(&context, tag_directives_copy)
457// yaml_free(value.handle)
458// yaml_free(value.prefix)
459// }
460// STACK_DEL(&context, tag_directives_copy)
461// yaml_free(value.handle)
462// yaml_free(value.prefix)
463//
464// return 0
465//}
466//
467///*
468// * Destroy a document object.
469// */
470//
471//YAML_DECLARE(void)
472//yaml_document_delete(document *yaml_document_t)
473//{
474// struct {
475// error yaml_error_type_t
476// } context
477// tag_directive *yaml_tag_directive_t
478//
479// context.error = YAML_NO_ERROR // Eliminate a compiler warning.
480//
481// assert(document) // Non-NULL document object is expected.
482//
483// while (!STACK_EMPTY(&context, document.nodes)) {
484// node yaml_node_t = POP(&context, document.nodes)
485// yaml_free(node.tag)
486// switch (node.type) {
487// case YAML_SCALAR_NODE:
488// yaml_free(node.data.scalar.value)
489// break
490// case YAML_SEQUENCE_NODE:
491// STACK_DEL(&context, node.data.sequence.items)
492// break
493// case YAML_MAPPING_NODE:
494// STACK_DEL(&context, node.data.mapping.pairs)
495// break
496// default:
497// assert(0) // Should not happen.
498// }
499// }
500// STACK_DEL(&context, document.nodes)
501//
502// yaml_free(document.version_directive)
503// for (tag_directive = document.tag_directives.start
504// tag_directive != document.tag_directives.end
505// tag_directive++) {
506// yaml_free(tag_directive.handle)
507// yaml_free(tag_directive.prefix)
508// }
509// yaml_free(document.tag_directives.start)
510//
511// memset(document, 0, sizeof(yaml_document_t))
512//}
513//
514///**
515// * Get a document node.
516// */
517//
518//YAML_DECLARE(yaml_node_t *)
519//yaml_document_get_node(document *yaml_document_t, index int)
520//{
521// assert(document) // Non-NULL document object is expected.
522//
523// if (index > 0 && document.nodes.start + index <= document.nodes.top) {
524// return document.nodes.start + index - 1
525// }
526// return NULL
527//}
528//
529///**
530// * Get the root object.
531// */
532//
533//YAML_DECLARE(yaml_node_t *)
534//yaml_document_get_root_node(document *yaml_document_t)
535//{
536// assert(document) // Non-NULL document object is expected.
537//
538// if (document.nodes.top != document.nodes.start) {
539// return document.nodes.start
540// }
541// return NULL
542//}
543//
544///*
545// * Add a scalar node to a document.
546// */
547//
548//YAML_DECLARE(int)
549//yaml_document_add_scalar(document *yaml_document_t,
550// tag *yaml_char_t, value *yaml_char_t, length int,
551// style yaml_scalar_style_t)
552//{
553// struct {
554// error yaml_error_type_t
555// } context
556// mark yaml_mark_t = { 0, 0, 0 }
557// tag_copy *yaml_char_t = NULL
558// value_copy *yaml_char_t = NULL
559// node yaml_node_t
560//
561// assert(document) // Non-NULL document object is expected.
562// assert(value) // Non-NULL value is expected.
563//
564// if (!tag) {
565// tag = (yaml_char_t *)YAML_DEFAULT_SCALAR_TAG
566// }
567//
568// if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
569// tag_copy = yaml_strdup(tag)
570// if (!tag_copy) goto error
571//
572// if (length < 0) {
573// length = strlen((char *)value)
574// }
575//
576// if (!yaml_check_utf8(value, length)) goto error
577// value_copy = yaml_malloc(length+1)
578// if (!value_copy) goto error
579// memcpy(value_copy, value, length)
580// value_copy[length] = '\0'
581//
582// SCALAR_NODE_INIT(node, tag_copy, value_copy, length, style, mark, mark)
583// if (!PUSH(&context, document.nodes, node)) goto error
584//
585// return document.nodes.top - document.nodes.start
586//
587//error:
588// yaml_free(tag_copy)
589// yaml_free(value_copy)
590//
591// return 0
592//}
593//
594///*
595// * Add a sequence node to a document.
596// */
597//
598//YAML_DECLARE(int)
599//yaml_document_add_sequence(document *yaml_document_t,
600// tag *yaml_char_t, style yaml_sequence_style_t)
601//{
602// struct {
603// error yaml_error_type_t
604// } context
605// mark yaml_mark_t = { 0, 0, 0 }
606// tag_copy *yaml_char_t = NULL
607// struct {
608// start *yaml_node_item_t
609// end *yaml_node_item_t
610// top *yaml_node_item_t
611// } items = { NULL, NULL, NULL }
612// node yaml_node_t
613//
614// assert(document) // Non-NULL document object is expected.
615//
616// if (!tag) {
617// tag = (yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG
618// }
619//
620// if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
621// tag_copy = yaml_strdup(tag)
622// if (!tag_copy) goto error
623//
624// if (!STACK_INIT(&context, items, INITIAL_STACK_SIZE)) goto error
625//
626// SEQUENCE_NODE_INIT(node, tag_copy, items.start, items.end,
627// style, mark, mark)
628// if (!PUSH(&context, document.nodes, node)) goto error
629//
630// return document.nodes.top - document.nodes.start
631//
632//error:
633// STACK_DEL(&context, items)
634// yaml_free(tag_copy)
635//
636// return 0
637//}
638//
639///*
640// * Add a mapping node to a document.
641// */
642//
643//YAML_DECLARE(int)
644//yaml_document_add_mapping(document *yaml_document_t,
645// tag *yaml_char_t, style yaml_mapping_style_t)
646//{
647// struct {
648// error yaml_error_type_t
649// } context
650// mark yaml_mark_t = { 0, 0, 0 }
651// tag_copy *yaml_char_t = NULL
652// struct {
653// start *yaml_node_pair_t
654// end *yaml_node_pair_t
655// top *yaml_node_pair_t
656// } pairs = { NULL, NULL, NULL }
657// node yaml_node_t
658//
659// assert(document) // Non-NULL document object is expected.
660//
661// if (!tag) {
662// tag = (yaml_char_t *)YAML_DEFAULT_MAPPING_TAG
663// }
664//
665// if (!yaml_check_utf8(tag, strlen((char *)tag))) goto error
666// tag_copy = yaml_strdup(tag)
667// if (!tag_copy) goto error
668//
669// if (!STACK_INIT(&context, pairs, INITIAL_STACK_SIZE)) goto error
670//
671// MAPPING_NODE_INIT(node, tag_copy, pairs.start, pairs.end,
672// style, mark, mark)
673// if (!PUSH(&context, document.nodes, node)) goto error
674//
675// return document.nodes.top - document.nodes.start
676//
677//error:
678// STACK_DEL(&context, pairs)
679// yaml_free(tag_copy)
680//
681// return 0
682//}
683//
684///*
685// * Append an item to a sequence node.
686// */
687//
688//YAML_DECLARE(int)
689//yaml_document_append_sequence_item(document *yaml_document_t,
690// sequence int, item int)
691//{
692// struct {
693// error yaml_error_type_t
694// } context
695//
696// assert(document) // Non-NULL document is required.
697// assert(sequence > 0
698// && document.nodes.start + sequence <= document.nodes.top)
699// // Valid sequence id is required.
700// assert(document.nodes.start[sequence-1].type == YAML_SEQUENCE_NODE)
701// // A sequence node is required.
702// assert(item > 0 && document.nodes.start + item <= document.nodes.top)
703// // Valid item id is required.
704//
705// if (!PUSH(&context,
706// document.nodes.start[sequence-1].data.sequence.items, item))
707// return 0
708//
709// return 1
710//}
711//
712///*
713// * Append a pair of a key and a value to a mapping node.
714// */
715//
716//YAML_DECLARE(int)
717//yaml_document_append_mapping_pair(document *yaml_document_t,
718// mapping int, key int, value int)
719//{
720// struct {
721// error yaml_error_type_t
722// } context
723//
724// pair yaml_node_pair_t
725//
726// assert(document) // Non-NULL document is required.
727// assert(mapping > 0
728// && document.nodes.start + mapping <= document.nodes.top)
729// // Valid mapping id is required.
730// assert(document.nodes.start[mapping-1].type == YAML_MAPPING_NODE)
731// // A mapping node is required.
732// assert(key > 0 && document.nodes.start + key <= document.nodes.top)
733// // Valid key id is required.
734// assert(value > 0 && document.nodes.start + value <= document.nodes.top)
735// // Valid value id is required.
736//
737// pair.key = key
738// pair.value = value
739//
740// if (!PUSH(&context,
741// document.nodes.start[mapping-1].data.mapping.pairs, pair))
742// return 0
743//
744// return 1
745//}
746//
747//