Ruby 2.0.0p247(2013-06-27revision41674)

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scanner.c
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1
2 /*
3 * Introduction
4 * ************
5 *
6 * The following notes assume that you are familiar with the YAML specification
7 * (http://yaml.org/spec/cvs/current.html). We mostly follow it, although in
8 * some cases we are less restrictive that it requires.
9 *
10 * The process of transforming a YAML stream into a sequence of events is
11 * divided on two steps: Scanning and Parsing.
12 *
13 * The Scanner transforms the input stream into a sequence of tokens, while the
14 * parser transform the sequence of tokens produced by the Scanner into a
15 * sequence of parsing events.
16 *
17 * The Scanner is rather clever and complicated. The Parser, on the contrary,
18 * is a straightforward implementation of a recursive-descendant parser (or,
19 * LL(1) parser, as it is usually called).
20 *
21 * Actually there are two issues of Scanning that might be called "clever", the
22 * rest is quite straightforward. The issues are "block collection start" and
23 * "simple keys". Both issues are explained below in details.
24 *
25 * Here the Scanning step is explained and implemented. We start with the list
26 * of all the tokens produced by the Scanner together with short descriptions.
27 *
28 * Now, tokens:
29 *
30 * STREAM-START(encoding) # The stream start.
31 * STREAM-END # The stream end.
32 * VERSION-DIRECTIVE(major,minor) # The '%YAML' directive.
33 * TAG-DIRECTIVE(handle,prefix) # The '%TAG' directive.
34 * DOCUMENT-START # '---'
35 * DOCUMENT-END # '...'
36 * BLOCK-SEQUENCE-START # Indentation increase denoting a block
37 * BLOCK-MAPPING-START # sequence or a block mapping.
38 * BLOCK-END # Indentation decrease.
39 * FLOW-SEQUENCE-START # '['
40 * FLOW-SEQUENCE-END # ']'
41 * BLOCK-SEQUENCE-START # '{'
42 * BLOCK-SEQUENCE-END # '}'
43 * BLOCK-ENTRY # '-'
44 * FLOW-ENTRY # ','
45 * KEY # '?' or nothing (simple keys).
46 * VALUE # ':'
47 * ALIAS(anchor) # '*anchor'
48 * ANCHOR(anchor) # '&anchor'
49 * TAG(handle,suffix) # '!handle!suffix'
50 * SCALAR(value,style) # A scalar.
51 *
52 * The following two tokens are "virtual" tokens denoting the beginning and the
53 * end of the stream:
54 *
55 * STREAM-START(encoding)
56 * STREAM-END
57 *
58 * We pass the information about the input stream encoding with the
59 * STREAM-START token.
60 *
61 * The next two tokens are responsible for tags:
62 *
63 * VERSION-DIRECTIVE(major,minor)
64 * TAG-DIRECTIVE(handle,prefix)
65 *
66 * Example:
67 *
68 * %YAML 1.1
69 * %TAG ! !foo
70 * %TAG !yaml! tag:yaml.org,2002:
71 * ---
72 *
73 * The correspoding sequence of tokens:
74 *
75 * STREAM-START(utf-8)
76 * VERSION-DIRECTIVE(1,1)
77 * TAG-DIRECTIVE("!","!foo")
78 * TAG-DIRECTIVE("!yaml","tag:yaml.org,2002:")
79 * DOCUMENT-START
80 * STREAM-END
81 *
82 * Note that the VERSION-DIRECTIVE and TAG-DIRECTIVE tokens occupy a whole
83 * line.
84 *
85 * The document start and end indicators are represented by:
86 *
87 * DOCUMENT-START
88 * DOCUMENT-END
89 *
90 * Note that if a YAML stream contains an implicit document (without '---'
91 * and '...' indicators), no DOCUMENT-START and DOCUMENT-END tokens will be
92 * produced.
93 *
94 * In the following examples, we present whole documents together with the
95 * produced tokens.
96 *
97 * 1. An implicit document:
98 *
99 * 'a scalar'
100 *
101 * Tokens:
102 *
103 * STREAM-START(utf-8)
104 * SCALAR("a scalar",single-quoted)
105 * STREAM-END
106 *
107 * 2. An explicit document:
108 *
109 * ---
110 * 'a scalar'
111 * ...
112 *
113 * Tokens:
114 *
115 * STREAM-START(utf-8)
116 * DOCUMENT-START
117 * SCALAR("a scalar",single-quoted)
118 * DOCUMENT-END
119 * STREAM-END
120 *
121 * 3. Several documents in a stream:
122 *
123 * 'a scalar'
124 * ---
125 * 'another scalar'
126 * ---
127 * 'yet another scalar'
128 *
129 * Tokens:
130 *
131 * STREAM-START(utf-8)
132 * SCALAR("a scalar",single-quoted)
133 * DOCUMENT-START
134 * SCALAR("another scalar",single-quoted)
135 * DOCUMENT-START
136 * SCALAR("yet another scalar",single-quoted)
137 * STREAM-END
138 *
139 * We have already introduced the SCALAR token above. The following tokens are
140 * used to describe aliases, anchors, tag, and scalars:
141 *
142 * ALIAS(anchor)
143 * ANCHOR(anchor)
144 * TAG(handle,suffix)
145 * SCALAR(value,style)
146 *
147 * The following series of examples illustrate the usage of these tokens:
148 *
149 * 1. A recursive sequence:
150 *
151 * &A [ *A ]
152 *
153 * Tokens:
154 *
155 * STREAM-START(utf-8)
156 * ANCHOR("A")
157 * FLOW-SEQUENCE-START
158 * ALIAS("A")
159 * FLOW-SEQUENCE-END
160 * STREAM-END
161 *
162 * 2. A tagged scalar:
163 *
164 * !!float "3.14" # A good approximation.
165 *
166 * Tokens:
167 *
168 * STREAM-START(utf-8)
169 * TAG("!!","float")
170 * SCALAR("3.14",double-quoted)
171 * STREAM-END
172 *
173 * 3. Various scalar styles:
174 *
175 * --- # Implicit empty plain scalars do not produce tokens.
176 * --- a plain scalar
177 * --- 'a single-quoted scalar'
178 * --- "a double-quoted scalar"
179 * --- |-
180 * a literal scalar
181 * --- >-
182 * a folded
183 * scalar
184 *
185 * Tokens:
186 *
187 * STREAM-START(utf-8)
188 * DOCUMENT-START
189 * DOCUMENT-START
190 * SCALAR("a plain scalar",plain)
191 * DOCUMENT-START
192 * SCALAR("a single-quoted scalar",single-quoted)
193 * DOCUMENT-START
194 * SCALAR("a double-quoted scalar",double-quoted)
195 * DOCUMENT-START
196 * SCALAR("a literal scalar",literal)
197 * DOCUMENT-START
198 * SCALAR("a folded scalar",folded)
199 * STREAM-END
200 *
201 * Now it's time to review collection-related tokens. We will start with
202 * flow collections:
203 *
204 * FLOW-SEQUENCE-START
205 * FLOW-SEQUENCE-END
206 * FLOW-MAPPING-START
207 * FLOW-MAPPING-END
208 * FLOW-ENTRY
209 * KEY
210 * VALUE
211 *
212 * The tokens FLOW-SEQUENCE-START, FLOW-SEQUENCE-END, FLOW-MAPPING-START, and
213 * FLOW-MAPPING-END represent the indicators '[', ']', '{', and '}'
214 * correspondingly. FLOW-ENTRY represent the ',' indicator. Finally the
215 * indicators '?' and ':', which are used for denoting mapping keys and values,
216 * are represented by the KEY and VALUE tokens.
217 *
218 * The following examples show flow collections:
219 *
220 * 1. A flow sequence:
221 *
222 * [item 1, item 2, item 3]
223 *
224 * Tokens:
225 *
226 * STREAM-START(utf-8)
227 * FLOW-SEQUENCE-START
228 * SCALAR("item 1",plain)
229 * FLOW-ENTRY
230 * SCALAR("item 2",plain)
231 * FLOW-ENTRY
232 * SCALAR("item 3",plain)
233 * FLOW-SEQUENCE-END
234 * STREAM-END
235 *
236 * 2. A flow mapping:
237 *
238 * {
239 * a simple key: a value, # Note that the KEY token is produced.
240 * ? a complex key: another value,
241 * }
242 *
243 * Tokens:
244 *
245 * STREAM-START(utf-8)
246 * FLOW-MAPPING-START
247 * KEY
248 * SCALAR("a simple key",plain)
249 * VALUE
250 * SCALAR("a value",plain)
251 * FLOW-ENTRY
252 * KEY
253 * SCALAR("a complex key",plain)
254 * VALUE
255 * SCALAR("another value",plain)
256 * FLOW-ENTRY
257 * FLOW-MAPPING-END
258 * STREAM-END
259 *
260 * A simple key is a key which is not denoted by the '?' indicator. Note that
261 * the Scanner still produce the KEY token whenever it encounters a simple key.
262 *
263 * For scanning block collections, the following tokens are used (note that we
264 * repeat KEY and VALUE here):
265 *
266 * BLOCK-SEQUENCE-START
267 * BLOCK-MAPPING-START
268 * BLOCK-END
269 * BLOCK-ENTRY
270 * KEY
271 * VALUE
272 *
273 * The tokens BLOCK-SEQUENCE-START and BLOCK-MAPPING-START denote indentation
274 * increase that precedes a block collection (cf. the INDENT token in Python).
275 * The token BLOCK-END denote indentation decrease that ends a block collection
276 * (cf. the DEDENT token in Python). However YAML has some syntax pecularities
277 * that makes detections of these tokens more complex.
278 *
279 * The tokens BLOCK-ENTRY, KEY, and VALUE are used to represent the indicators
280 * '-', '?', and ':' correspondingly.
281 *
282 * The following examples show how the tokens BLOCK-SEQUENCE-START,
283 * BLOCK-MAPPING-START, and BLOCK-END are emitted by the Scanner:
284 *
285 * 1. Block sequences:
286 *
287 * - item 1
288 * - item 2
289 * -
290 * - item 3.1
291 * - item 3.2
292 * -
293 * key 1: value 1
294 * key 2: value 2
295 *
296 * Tokens:
297 *
298 * STREAM-START(utf-8)
299 * BLOCK-SEQUENCE-START
300 * BLOCK-ENTRY
301 * SCALAR("item 1",plain)
302 * BLOCK-ENTRY
303 * SCALAR("item 2",plain)
304 * BLOCK-ENTRY
305 * BLOCK-SEQUENCE-START
306 * BLOCK-ENTRY
307 * SCALAR("item 3.1",plain)
308 * BLOCK-ENTRY
309 * SCALAR("item 3.2",plain)
310 * BLOCK-END
311 * BLOCK-ENTRY
312 * BLOCK-MAPPING-START
313 * KEY
314 * SCALAR("key 1",plain)
315 * VALUE
316 * SCALAR("value 1",plain)
317 * KEY
318 * SCALAR("key 2",plain)
319 * VALUE
320 * SCALAR("value 2",plain)
321 * BLOCK-END
322 * BLOCK-END
323 * STREAM-END
324 *
325 * 2. Block mappings:
326 *
327 * a simple key: a value # The KEY token is produced here.
328 * ? a complex key
329 * : another value
330 * a mapping:
331 * key 1: value 1
332 * key 2: value 2
333 * a sequence:
334 * - item 1
335 * - item 2
336 *
337 * Tokens:
338 *
339 * STREAM-START(utf-8)
340 * BLOCK-MAPPING-START
341 * KEY
342 * SCALAR("a simple key",plain)
343 * VALUE
344 * SCALAR("a value",plain)
345 * KEY
346 * SCALAR("a complex key",plain)
347 * VALUE
348 * SCALAR("another value",plain)
349 * KEY
350 * SCALAR("a mapping",plain)
351 * BLOCK-MAPPING-START
352 * KEY
353 * SCALAR("key 1",plain)
354 * VALUE
355 * SCALAR("value 1",plain)
356 * KEY
357 * SCALAR("key 2",plain)
358 * VALUE
359 * SCALAR("value 2",plain)
360 * BLOCK-END
361 * KEY
362 * SCALAR("a sequence",plain)
363 * VALUE
364 * BLOCK-SEQUENCE-START
365 * BLOCK-ENTRY
366 * SCALAR("item 1",plain)
367 * BLOCK-ENTRY
368 * SCALAR("item 2",plain)
369 * BLOCK-END
370 * BLOCK-END
371 * STREAM-END
372 *
373 * YAML does not always require to start a new block collection from a new
374 * line. If the current line contains only '-', '?', and ':' indicators, a new
375 * block collection may start at the current line. The following examples
376 * illustrate this case:
377 *
378 * 1. Collections in a sequence:
379 *
380 * - - item 1
381 * - item 2
382 * - key 1: value 1
383 * key 2: value 2
384 * - ? complex key
385 * : complex value
386 *
387 * Tokens:
388 *
389 * STREAM-START(utf-8)
390 * BLOCK-SEQUENCE-START
391 * BLOCK-ENTRY
392 * BLOCK-SEQUENCE-START
393 * BLOCK-ENTRY
394 * SCALAR("item 1",plain)
395 * BLOCK-ENTRY
396 * SCALAR("item 2",plain)
397 * BLOCK-END
398 * BLOCK-ENTRY
399 * BLOCK-MAPPING-START
400 * KEY
401 * SCALAR("key 1",plain)
402 * VALUE
403 * SCALAR("value 1",plain)
404 * KEY
405 * SCALAR("key 2",plain)
406 * VALUE
407 * SCALAR("value 2",plain)
408 * BLOCK-END
409 * BLOCK-ENTRY
410 * BLOCK-MAPPING-START
411 * KEY
412 * SCALAR("complex key")
413 * VALUE
414 * SCALAR("complex value")
415 * BLOCK-END
416 * BLOCK-END
417 * STREAM-END
418 *
419 * 2. Collections in a mapping:
420 *
421 * ? a sequence
422 * : - item 1
423 * - item 2
424 * ? a mapping
425 * : key 1: value 1
426 * key 2: value 2
427 *
428 * Tokens:
429 *
430 * STREAM-START(utf-8)
431 * BLOCK-MAPPING-START
432 * KEY
433 * SCALAR("a sequence",plain)
434 * VALUE
435 * BLOCK-SEQUENCE-START
436 * BLOCK-ENTRY
437 * SCALAR("item 1",plain)
438 * BLOCK-ENTRY
439 * SCALAR("item 2",plain)
440 * BLOCK-END
441 * KEY
442 * SCALAR("a mapping",plain)
443 * VALUE
444 * BLOCK-MAPPING-START
445 * KEY
446 * SCALAR("key 1",plain)
447 * VALUE
448 * SCALAR("value 1",plain)
449 * KEY
450 * SCALAR("key 2",plain)
451 * VALUE
452 * SCALAR("value 2",plain)
453 * BLOCK-END
454 * BLOCK-END
455 * STREAM-END
456 *
457 * YAML also permits non-indented sequences if they are included into a block
458 * mapping. In this case, the token BLOCK-SEQUENCE-START is not produced:
459 *
460 * key:
461 * - item 1 # BLOCK-SEQUENCE-START is NOT produced here.
462 * - item 2
463 *
464 * Tokens:
465 *
466 * STREAM-START(utf-8)
467 * BLOCK-MAPPING-START
468 * KEY
469 * SCALAR("key",plain)
470 * VALUE
471 * BLOCK-ENTRY
472 * SCALAR("item 1",plain)
473 * BLOCK-ENTRY
474 * SCALAR("item 2",plain)
475 * BLOCK-END
476 */
477
478 #include "yaml_private.h"
479
480 /*
481 * Ensure that the buffer contains the required number of characters.
482 * Return 1 on success, 0 on failure (reader error or memory error).
483 */
484
485 #define CACHE(parser,length) \
486 (parser->unread >= (length) \
487 ? 1 \
488 : yaml_parser_update_buffer(parser, (length)))
489
490 /*
491 * Advance the buffer pointer.
492 */
493
494 #define SKIP(parser) \
495 (parser->mark.index ++, \
496 parser->mark.column ++, \
497 parser->unread --, \
498 parser->buffer.pointer += WIDTH(parser->buffer))
499
500 #define SKIP_LINE(parser) \
501 (IS_CRLF(parser->buffer) ? \
502 (parser->mark.index += 2, \
503 parser->mark.column = 0, \
504 parser->mark.line ++, \
505 parser->unread -= 2, \
506 parser->buffer.pointer += 2) : \
507 IS_BREAK(parser->buffer) ? \
508 (parser->mark.index ++, \
509 parser->mark.column = 0, \
510 parser->mark.line ++, \
511 parser->unread --, \
512 parser->buffer.pointer += WIDTH(parser->buffer)) : 0)
513
514 /*
515 * Copy a character to a string buffer and advance pointers.
516 */
517
518 #define READ(parser,string) \
519 (STRING_EXTEND(parser,string) ? \
520 (COPY(string,parser->buffer), \
521 parser->mark.index ++, \
522 parser->mark.column ++, \
523 parser->unread --, \
524 1) : 0)
525
526 /*
527 * Copy a line break character to a string buffer and advance pointers.
528 */
529
530 #define READ_LINE(parser,string) \
531 (STRING_EXTEND(parser,string) ? \
532 (((CHECK_AT(parser->buffer,'\r',0) \
533 && CHECK_AT(parser->buffer,'\n',1)) ? /* CR LF -> LF */ \
534 (*((string).pointer++) = (yaml_char_t) '\n', \
535 parser->buffer.pointer += 2, \
536 parser->mark.index += 2, \
537 parser->mark.column = 0, \
538 parser->mark.line ++, \
539 parser->unread -= 2) : \
540 (CHECK_AT(parser->buffer,'\r',0) \
541 || CHECK_AT(parser->buffer,'\n',0)) ? /* CR|LF -> LF */ \
542 (*((string).pointer++) = (yaml_char_t) '\n', \
543 parser->buffer.pointer ++, \
544 parser->mark.index ++, \
545 parser->mark.column = 0, \
546 parser->mark.line ++, \
547 parser->unread --) : \
548 (CHECK_AT(parser->buffer,'\xC2',0) \
549 && CHECK_AT(parser->buffer,'\x85',1)) ? /* NEL -> LF */ \
550 (*((string).pointer++) = (yaml_char_t) '\n', \
551 parser->buffer.pointer += 2, \
552 parser->mark.index ++, \
553 parser->mark.column = 0, \
554 parser->mark.line ++, \
555 parser->unread --) : \
556 (CHECK_AT(parser->buffer,'\xE2',0) && \
557 CHECK_AT(parser->buffer,'\x80',1) && \
558 (CHECK_AT(parser->buffer,'\xA8',2) || \
559 CHECK_AT(parser->buffer,'\xA9',2))) ? /* LS|PS -> LS|PS */ \
560 (*((string).pointer++) = *(parser->buffer.pointer++), \
561 *((string).pointer++) = *(parser->buffer.pointer++), \
562 *((string).pointer++) = *(parser->buffer.pointer++), \
563 parser->mark.index ++, \
564 parser->mark.column = 0, \
565 parser->mark.line ++, \
566 parser->unread --) : 0), \
567 1) : 0)
568
569 /*
570 * Public API declarations.
571 */
572
573 YAML_DECLARE(int)
574 yaml_parser_scan(yaml_parser_t *parser, yaml_token_t *token);
575
576 /*
577 * Error handling.
578 */
579
580 static int
581 yaml_parser_set_scanner_error(yaml_parser_t *parser, const char *context,
582 yaml_mark_t context_mark, const char *problem);
583
584 /*
585 * High-level token API.
586 */
587
588 YAML_DECLARE(int)
589 yaml_parser_fetch_more_tokens(yaml_parser_t *parser);
590
591 static int
592 yaml_parser_fetch_next_token(yaml_parser_t *parser);
593
594 /*
595 * Potential simple keys.
596 */
597
598 static int
599 yaml_parser_stale_simple_keys(yaml_parser_t *parser);
600
601 static int
602 yaml_parser_save_simple_key(yaml_parser_t *parser);
603
604 static int
605 yaml_parser_remove_simple_key(yaml_parser_t *parser);
606
607 static int
608 yaml_parser_increase_flow_level(yaml_parser_t *parser);
609
610 static int
611 yaml_parser_decrease_flow_level(yaml_parser_t *parser);
612
613 /*
614 * Indentation treatment.
615 */
616
617 static int
618 yaml_parser_roll_indent(yaml_parser_t *parser, int column,
619 int number, yaml_token_type_t type, yaml_mark_t mark);
620
621 static int
622 yaml_parser_unroll_indent(yaml_parser_t *parser, int column);
623
624 /*
625 * Token fetchers.
626 */
627
628 static int
629 yaml_parser_fetch_stream_start(yaml_parser_t *parser);
630
631 static int
632 yaml_parser_fetch_stream_end(yaml_parser_t *parser);
633
634 static int
635 yaml_parser_fetch_directive(yaml_parser_t *parser);
636
637 static int
638 yaml_parser_fetch_document_indicator(yaml_parser_t *parser,
639 yaml_token_type_t type);
640
641 static int
642 yaml_parser_fetch_flow_collection_start(yaml_parser_t *parser,
643 yaml_token_type_t type);
644
645 static int
646 yaml_parser_fetch_flow_collection_end(yaml_parser_t *parser,
647 yaml_token_type_t type);
648
649 static int
650 yaml_parser_fetch_flow_entry(yaml_parser_t *parser);
651
652 static int
653 yaml_parser_fetch_block_entry(yaml_parser_t *parser);
654
655 static int
656 yaml_parser_fetch_key(yaml_parser_t *parser);
657
658 static int
659 yaml_parser_fetch_value(yaml_parser_t *parser);
660
661 static int
662 yaml_parser_fetch_anchor(yaml_parser_t *parser, yaml_token_type_t type);
663
664 static int
665 yaml_parser_fetch_tag(yaml_parser_t *parser);
666
667 static int
668 yaml_parser_fetch_block_scalar(yaml_parser_t *parser, int literal);
669
670 static int
671 yaml_parser_fetch_flow_scalar(yaml_parser_t *parser, int single);
672
673 static int
674 yaml_parser_fetch_plain_scalar(yaml_parser_t *parser);
675
676 /*
677 * Token scanners.
678 */
679
680 static int
681 yaml_parser_scan_to_next_token(yaml_parser_t *parser);
682
683 static int
684 yaml_parser_scan_directive(yaml_parser_t *parser, yaml_token_t *token);
685
686 static int
687 yaml_parser_scan_directive_name(yaml_parser_t *parser,
688 yaml_mark_t start_mark, yaml_char_t **name);
689
690 static int
691 yaml_parser_scan_version_directive_value(yaml_parser_t *parser,
692 yaml_mark_t start_mark, int *major, int *minor);
693
694 static int
695 yaml_parser_scan_version_directive_number(yaml_parser_t *parser,
696 yaml_mark_t start_mark, int *number);
697
698 static int
699 yaml_parser_scan_tag_directive_value(yaml_parser_t *parser,
700 yaml_mark_t mark, yaml_char_t **handle, yaml_char_t **prefix);
701
702 static int
703 yaml_parser_scan_anchor(yaml_parser_t *parser, yaml_token_t *token,
704 yaml_token_type_t type);
705
706 static int
707 yaml_parser_scan_tag(yaml_parser_t *parser, yaml_token_t *token);
708
709 static int
710 yaml_parser_scan_tag_handle(yaml_parser_t *parser, int directive,
711 yaml_mark_t start_mark, yaml_char_t **handle);
712
713 static int
714 yaml_parser_scan_tag_uri(yaml_parser_t *parser, int directive,
715 yaml_char_t *head, yaml_mark_t start_mark, yaml_char_t **uri);
716
717 static int
718 yaml_parser_scan_uri_escapes(yaml_parser_t *parser, int directive,
719 yaml_mark_t start_mark, yaml_string_t *string);
720
721 static int
722 yaml_parser_scan_block_scalar(yaml_parser_t *parser, yaml_token_t *token,
723 int literal);
724
725 static int
726 yaml_parser_scan_block_scalar_breaks(yaml_parser_t *parser,
727 int *indent, yaml_string_t *breaks,
728 yaml_mark_t start_mark, yaml_mark_t *end_mark);
729
730 static int
731 yaml_parser_scan_flow_scalar(yaml_parser_t *parser, yaml_token_t *token,
732 int single);
733
734 static int
735 yaml_parser_scan_plain_scalar(yaml_parser_t *parser, yaml_token_t *token);
736
737 /*
738 * Get the next token.
739 */
740
741 YAML_DECLARE(int)
742 yaml_parser_scan(yaml_parser_t *parser, yaml_token_t *token)
743 {
744 assert(parser); /* Non-NULL parser object is expected. */
745 assert(token); /* Non-NULL token object is expected. */
746
747 /* Erase the token object. */
748
749 memset(token, 0, sizeof(yaml_token_t));
750
751 /* No tokens after STREAM-END or error. */
752
753 if (parser->stream_end_produced || parser->error) {
754 return 1;
755 }
756
757 /* Ensure that the tokens queue contains enough tokens. */
758
759 if (!parser->token_available) {
760 if (!yaml_parser_fetch_more_tokens(parser))
761 return 0;
762 }
763
764 /* Fetch the next token from the queue. */
765
766 *token = DEQUEUE(parser, parser->tokens);
767 parser->token_available = 0;
768 parser->tokens_parsed ++;
769
770 if (token->type == YAML_STREAM_END_TOKEN) {
771 parser->stream_end_produced = 1;
772 }
773
774 return 1;
775 }
776
777 /*
778 * Set the scanner error and return 0.
779 */
780
781 static int
782 yaml_parser_set_scanner_error(yaml_parser_t *parser, const char *context,
783 yaml_mark_t context_mark, const char *problem)
784 {
785 parser->error = YAML_SCANNER_ERROR;
786 parser->context = context;
787 parser->context_mark = context_mark;
788 parser->problem = problem;
789 parser->problem_mark = parser->mark;
790
791 return 0;
792 }
793
794 /*
795 * Ensure that the tokens queue contains at least one token which can be
796 * returned to the Parser.
797 */
798
799 YAML_DECLARE(int)
800 yaml_parser_fetch_more_tokens(yaml_parser_t *parser)
801 {
802 int need_more_tokens;
803
804 /* While we need more tokens to fetch, do it. */
805
806 while (1)
807 {
808 /*
809 * Check if we really need to fetch more tokens.
810 */
811
812 need_more_tokens = 0;
813
814 if (parser->tokens.head == parser->tokens.tail)
815 {
816 /* Queue is empty. */
817
818 need_more_tokens = 1;
819 }
820 else
821 {
822 yaml_simple_key_t *simple_key;
823
824 /* Check if any potential simple key may occupy the head position. */
825
826 if (!yaml_parser_stale_simple_keys(parser))
827 return 0;
828
829 for (simple_key = parser->simple_keys.start;
830 simple_key != parser->simple_keys.top; simple_key++) {
831 if (simple_key->possible
832 && simple_key->token_number == parser->tokens_parsed) {
833 need_more_tokens = 1;
834 break;
835 }
836 }
837 }
838
839 /* We are finished. */
840
841 if (!need_more_tokens)
842 break;
843
844 /* Fetch the next token. */
845
846 if (!yaml_parser_fetch_next_token(parser))
847 return 0;
848 }
849
850 parser->token_available = 1;
851
852 return 1;
853 }
854
855 /*
856 * The dispatcher for token fetchers.
857 */
858
859 static int
860 yaml_parser_fetch_next_token(yaml_parser_t *parser)
861 {
862 /* Ensure that the buffer is initialized. */
863
864 if (!CACHE(parser, 1))
865 return 0;
866
867 /* Check if we just started scanning. Fetch STREAM-START then. */
868
869 if (!parser->stream_start_produced)
870 return yaml_parser_fetch_stream_start(parser);
871
872 /* Eat whitespaces and comments until we reach the next token. */
873
874 if (!yaml_parser_scan_to_next_token(parser))
875 return 0;
876
877 /* Remove obsolete potential simple keys. */
878
879 if (!yaml_parser_stale_simple_keys(parser))
880 return 0;
881
882 /* Check the indentation level against the current column. */
883
884 if (!yaml_parser_unroll_indent(parser, parser->mark.column))
885 return 0;
886
887 /*
888 * Ensure that the buffer contains at least 4 characters. 4 is the length
889 * of the longest indicators ('--- ' and '... ').
890 */
891
892 if (!CACHE(parser, 4))
893 return 0;
894
895 /* Is it the end of the stream? */
896
897 if (IS_Z(parser->buffer))
898 return yaml_parser_fetch_stream_end(parser);
899
900 /* Is it a directive? */
901
902 if (parser->mark.column == 0 && CHECK(parser->buffer, '%'))
903 return yaml_parser_fetch_directive(parser);
904
905 /* Is it the document start indicator? */
906
907 if (parser->mark.column == 0
908 && CHECK_AT(parser->buffer, '-', 0)
909 && CHECK_AT(parser->buffer, '-', 1)
910 && CHECK_AT(parser->buffer, '-', 2)
911 && IS_BLANKZ_AT(parser->buffer, 3))
912 return yaml_parser_fetch_document_indicator(parser,
913 YAML_DOCUMENT_START_TOKEN);
914
915 /* Is it the document end indicator? */
916
917 if (parser->mark.column == 0
918 && CHECK_AT(parser->buffer, '.', 0)
919 && CHECK_AT(parser->buffer, '.', 1)
920 && CHECK_AT(parser->buffer, '.', 2)
921 && IS_BLANKZ_AT(parser->buffer, 3))
922 return yaml_parser_fetch_document_indicator(parser,
923 YAML_DOCUMENT_END_TOKEN);
924
925 /* Is it the flow sequence start indicator? */
926
927 if (CHECK(parser->buffer, '['))
928 return yaml_parser_fetch_flow_collection_start(parser,
929 YAML_FLOW_SEQUENCE_START_TOKEN);
930
931 /* Is it the flow mapping start indicator? */
932
933 if (CHECK(parser->buffer, '{'))
934 return yaml_parser_fetch_flow_collection_start(parser,
935 YAML_FLOW_MAPPING_START_TOKEN);
936
937 /* Is it the flow sequence end indicator? */
938
939 if (CHECK(parser->buffer, ']'))
940 return yaml_parser_fetch_flow_collection_end(parser,
941 YAML_FLOW_SEQUENCE_END_TOKEN);
942
943 /* Is it the flow mapping end indicator? */
944
945 if (CHECK(parser->buffer, '}'))
946 return yaml_parser_fetch_flow_collection_end(parser,
947 YAML_FLOW_MAPPING_END_TOKEN);
948
949 /* Is it the flow entry indicator? */
950
951 if (CHECK(parser->buffer, ','))
952 return yaml_parser_fetch_flow_entry(parser);
953
954 /* Is it the block entry indicator? */
955
956 if (CHECK(parser->buffer, '-') && IS_BLANKZ_AT(parser->buffer, 1))
957 return yaml_parser_fetch_block_entry(parser);
958
959 /* Is it the key indicator? */
960
961 if (CHECK(parser->buffer, '?')
962 && (parser->flow_level || IS_BLANKZ_AT(parser->buffer, 1)))
963 return yaml_parser_fetch_key(parser);
964
965 /* Is it the value indicator? */
966
967 if (CHECK(parser->buffer, ':')
968 && (parser->flow_level || IS_BLANKZ_AT(parser->buffer, 1)))
969 return yaml_parser_fetch_value(parser);
970
971 /* Is it an alias? */
972
973 if (CHECK(parser->buffer, '*'))
974 return yaml_parser_fetch_anchor(parser, YAML_ALIAS_TOKEN);
975
976 /* Is it an anchor? */
977
978 if (CHECK(parser->buffer, '&'))
979 return yaml_parser_fetch_anchor(parser, YAML_ANCHOR_TOKEN);
980
981 /* Is it a tag? */
982
983 if (CHECK(parser->buffer, '!'))
984 return yaml_parser_fetch_tag(parser);
985
986 /* Is it a literal scalar? */
987
988 if (CHECK(parser->buffer, '|') && !parser->flow_level)
989 return yaml_parser_fetch_block_scalar(parser, 1);
990
991 /* Is it a folded scalar? */
992
993 if (CHECK(parser->buffer, '>') && !parser->flow_level)
994 return yaml_parser_fetch_block_scalar(parser, 0);
995
996 /* Is it a single-quoted scalar? */
997
998 if (CHECK(parser->buffer, '\''))
999 return yaml_parser_fetch_flow_scalar(parser, 1);
1000
1001 /* Is it a double-quoted scalar? */
1002
1003 if (CHECK(parser->buffer, '"'))
1004 return yaml_parser_fetch_flow_scalar(parser, 0);
1005
1006 /*
1007 * Is it a plain scalar?
1008 *
1009 * A plain scalar may start with any non-blank characters except
1010 *
1011 * '-', '?', ':', ',', '[', ']', '{', '}',
1012 * '#', '&', '*', '!', '|', '>', '\'', '\"',
1013 * '%', '@', '`'.
1014 *
1015 * In the block context (and, for the '-' indicator, in the flow context
1016 * too), it may also start with the characters
1017 *
1018 * '-', '?', ':'
1019 *
1020 * if it is followed by a non-space character.
1021 *
1022 * The last rule is more restrictive than the specification requires.
1023 */
1024
1025 if (!(IS_BLANKZ(parser->buffer) || CHECK(parser->buffer, '-')
1026 || CHECK(parser->buffer, '?') || CHECK(parser->buffer, ':')
1027 || CHECK(parser->buffer, ',') || CHECK(parser->buffer, '[')
1028 || CHECK(parser->buffer, ']') || CHECK(parser->buffer, '{')
1029 || CHECK(parser->buffer, '}') || CHECK(parser->buffer, '#')
1030 || CHECK(parser->buffer, '&') || CHECK(parser->buffer, '*')
1031 || CHECK(parser->buffer, '!') || CHECK(parser->buffer, '|')
1032 || CHECK(parser->buffer, '>') || CHECK(parser->buffer, '\'')
1033 || CHECK(parser->buffer, '"') || CHECK(parser->buffer, '%')
1034 || CHECK(parser->buffer, '@') || CHECK(parser->buffer, '`')) ||
1035 (CHECK(parser->buffer, '-') && !IS_BLANK_AT(parser->buffer, 1)) ||
1036 (!parser->flow_level &&
1037 (CHECK(parser->buffer, '?') || CHECK(parser->buffer, ':'))
1038 && !IS_BLANKZ_AT(parser->buffer, 1)))
1039 return yaml_parser_fetch_plain_scalar(parser);
1040
1041 /*
1042 * If we don't determine the token type so far, it is an error.
1043 */
1044
1045 return yaml_parser_set_scanner_error(parser,
1046 "while scanning for the next token", parser->mark,
1047 "found character that cannot start any token");
1048 }
1049
1050 /*
1051 * Check the list of potential simple keys and remove the positions that
1052 * cannot contain simple keys anymore.
1053 */
1054
1055 static int
1056 yaml_parser_stale_simple_keys(yaml_parser_t *parser)
1057 {
1058 yaml_simple_key_t *simple_key;
1059
1060 /* Check for a potential simple key for each flow level. */
1061
1062 for (simple_key = parser->simple_keys.start;
1063 simple_key != parser->simple_keys.top; simple_key ++)
1064 {
1065 /*
1066 * The specification requires that a simple key
1067 *
1068 * - is limited to a single line,
1069 * - is shorter than 1024 characters.
1070 */
1071
1072 if (simple_key->possible
1073 && (simple_key->mark.line < parser->mark.line
1074 || simple_key->mark.index+1024 < parser->mark.index)) {
1075
1076 /* Check if the potential simple key to be removed is required. */
1077
1078 if (simple_key->required) {
1079 return yaml_parser_set_scanner_error(parser,
1080 "while scanning a simple key", simple_key->mark,
1081 "could not find expected ':'");
1082 }
1083
1084 simple_key->possible = 0;
1085 }
1086 }
1087
1088 return 1;
1089 }
1090
1091 /*
1092 * Check if a simple key may start at the current position and add it if
1093 * needed.
1094 */
1095
1096 static int
1097 yaml_parser_save_simple_key(yaml_parser_t *parser)
1098 {
1099 /*
1100 * A simple key is required at the current position if the scanner is in
1101 * the block context and the current column coincides with the indentation
1102 * level.
1103 */
1104
1105 int required = (!parser->flow_level
1106 && parser->indent == (int)parser->mark.column);
1107
1108 /*
1109 * A simple key is required only when it is the first token in the current
1110 * line. Therefore it is always allowed. But we add a check anyway.
1111 */
1112
1113 assert(parser->simple_key_allowed || !required); /* Impossible. */
1114
1115 /*
1116 * If the current position may start a simple key, save it.
1117 */
1118
1119 if (parser->simple_key_allowed)
1120 {
1121 yaml_simple_key_t simple_key;
1122 simple_key.possible = 1;
1123 simple_key.required = required;
1124 simple_key.token_number =
1125 parser->tokens_parsed + (parser->tokens.tail - parser->tokens.head);
1126 simple_key.mark = parser->mark;
1127
1128 if (!yaml_parser_remove_simple_key(parser)) return 0;
1129
1130 *(parser->simple_keys.top-1) = simple_key;
1131 }
1132
1133 return 1;
1134 }
1135
1136 /*
1137 * Remove a potential simple key at the current flow level.
1138 */
1139
1140 static int
1141 yaml_parser_remove_simple_key(yaml_parser_t *parser)
1142 {
1143 yaml_simple_key_t *simple_key = parser->simple_keys.top-1;
1144
1145 if (simple_key->possible)
1146 {
1147 /* If the key is required, it is an error. */
1148
1149 if (simple_key->required) {
1150 return yaml_parser_set_scanner_error(parser,
1151 "while scanning a simple key", simple_key->mark,
1152 "could not find expected ':'");
1153 }
1154 }
1155
1156 /* Remove the key from the stack. */
1157
1158 simple_key->possible = 0;
1159
1160 return 1;
1161 }
1162
1163 /*
1164 * Increase the flow level and resize the simple key list if needed.
1165 */
1166
1167 static int
1168 yaml_parser_increase_flow_level(yaml_parser_t *parser)
1169 {
1170 yaml_simple_key_t empty_simple_key = { 0, 0, 0, { 0, 0, 0 } };
1171
1172 /* Reset the simple key on the next level. */
1173
1174 if (!PUSH(parser, parser->simple_keys, empty_simple_key))
1175 return 0;
1176
1177 /* Increase the flow level. */
1178
1179 parser->flow_level++;
1180
1181 return 1;
1182 }
1183
1184 /*
1185 * Decrease the flow level.
1186 */
1187
1188 static int
1189 yaml_parser_decrease_flow_level(yaml_parser_t *parser)
1190 {
1191 yaml_simple_key_t dummy_key; /* Used to eliminate a compiler warning. */
1192
1193 if (parser->flow_level) {
1194 parser->flow_level --;
1195 dummy_key = POP(parser, parser->simple_keys);
1196 }
1197
1198 return 1;
1199 }
1200
1201 /*
1202 * Push the current indentation level to the stack and set the new level
1203 * the current column is greater than the indentation level. In this case,
1204 * append or insert the specified token into the token queue.
1205 *
1206 */
1207
1208 static int
1209 yaml_parser_roll_indent(yaml_parser_t *parser, int column,
1210 int number, yaml_token_type_t type, yaml_mark_t mark)
1211 {
1212 yaml_token_t token;
1213
1214 /* In the flow context, do nothing. */
1215
1216 if (parser->flow_level)
1217 return 1;
1218
1219 if (parser->indent < column)
1220 {
1221 /*
1222 * Push the current indentation level to the stack and set the new
1223 * indentation level.
1224 */
1225
1226 if (!PUSH(parser, parser->indents, parser->indent))
1227 return 0;
1228
1229 parser->indent = column;
1230
1231 /* Create a token and insert it into the queue. */
1232
1233 TOKEN_INIT(token, type, mark, mark);
1234
1235 if (number == -1) {
1236 if (!ENQUEUE(parser, parser->tokens, token))
1237 return 0;
1238 }
1239 else {
1240 if (!QUEUE_INSERT(parser,
1241 parser->tokens, number - parser->tokens_parsed, token))
1242 return 0;
1243 }
1244 }
1245
1246 return 1;
1247 }
1248
1249 /*
1250 * Pop indentation levels from the indents stack until the current level
1251 * becomes less or equal to the column. For each indentation level, append
1252 * the BLOCK-END token.
1253 */
1254
1255
1256 static int
1257 yaml_parser_unroll_indent(yaml_parser_t *parser, int column)
1258 {
1259 yaml_token_t token;
1260
1261 /* In the flow context, do nothing. */
1262
1263 if (parser->flow_level)
1264 return 1;
1265
1266 /* Loop through the indentation levels in the stack. */
1267
1268 while (parser->indent > column)
1269 {
1270 /* Create a token and append it to the queue. */
1271
1272 TOKEN_INIT(token, YAML_BLOCK_END_TOKEN, parser->mark, parser->mark);
1273
1274 if (!ENQUEUE(parser, parser->tokens, token))
1275 return 0;
1276
1277 /* Pop the indentation level. */
1278
1279 parser->indent = POP(parser, parser->indents);
1280 }
1281
1282 return 1;
1283 }
1284
1285 /*
1286 * Initialize the scanner and produce the STREAM-START token.
1287 */
1288
1289 static int
1290 yaml_parser_fetch_stream_start(yaml_parser_t *parser)
1291 {
1292 yaml_simple_key_t simple_key = { 0, 0, 0, { 0, 0, 0 } };
1293 yaml_token_t token;
1294
1295 /* Set the initial indentation. */
1296
1297 parser->indent = -1;
1298
1299 /* Initialize the simple key stack. */
1300
1301 if (!PUSH(parser, parser->simple_keys, simple_key))
1302 return 0;
1303
1304 /* A simple key is allowed at the beginning of the stream. */
1305
1306 parser->simple_key_allowed = 1;
1307
1308 /* We have started. */
1309
1310 parser->stream_start_produced = 1;
1311
1312 /* Create the STREAM-START token and append it to the queue. */
1313
1314 STREAM_START_TOKEN_INIT(token, parser->encoding,
1315 parser->mark, parser->mark);
1316
1317 if (!ENQUEUE(parser, parser->tokens, token))
1318 return 0;
1319
1320 return 1;
1321 }
1322
1323 /*
1324 * Produce the STREAM-END token and shut down the scanner.
1325 */
1326
1327 static int
1328 yaml_parser_fetch_stream_end(yaml_parser_t *parser)
1329 {
1330 yaml_token_t token;
1331
1332 /* Force new line. */
1333
1334 if (parser->mark.column != 0) {
1335 parser->mark.column = 0;
1336 parser->mark.line ++;
1337 }
1338
1339 /* Reset the indentation level. */
1340
1341 if (!yaml_parser_unroll_indent(parser, -1))
1342 return 0;
1343
1344 /* Reset simple keys. */
1345
1346 if (!yaml_parser_remove_simple_key(parser))
1347 return 0;
1348
1349 parser->simple_key_allowed = 0;
1350
1351 /* Create the STREAM-END token and append it to the queue. */
1352
1353 STREAM_END_TOKEN_INIT(token, parser->mark, parser->mark);
1354
1355 if (!ENQUEUE(parser, parser->tokens, token))
1356 return 0;
1357
1358 return 1;
1359 }
1360
1361 /*
1362 * Produce a VERSION-DIRECTIVE or TAG-DIRECTIVE token.
1363 */
1364
1365 static int
1366 yaml_parser_fetch_directive(yaml_parser_t *parser)
1367 {
1368 yaml_token_t token;
1369
1370 /* Reset the indentation level. */
1371
1372 if (!yaml_parser_unroll_indent(parser, -1))
1373 return 0;
1374
1375 /* Reset simple keys. */
1376
1377 if (!yaml_parser_remove_simple_key(parser))
1378 return 0;
1379
1380 parser->simple_key_allowed = 0;
1381
1382 /* Create the YAML-DIRECTIVE or TAG-DIRECTIVE token. */
1383
1384 if (!yaml_parser_scan_directive(parser, &token))
1385 return 0;
1386
1387 /* Append the token to the queue. */
1388
1389 if (!ENQUEUE(parser, parser->tokens, token)) {
1390 yaml_token_delete(&token);
1391 return 0;
1392 }
1393
1394 return 1;
1395 }
1396
1397 /*
1398 * Produce the DOCUMENT-START or DOCUMENT-END token.
1399 */
1400
1401 static int
1402 yaml_parser_fetch_document_indicator(yaml_parser_t *parser,
1403 yaml_token_type_t type)
1404 {
1405 yaml_mark_t start_mark, end_mark;
1406 yaml_token_t token;
1407
1408 /* Reset the indentation level. */
1409
1410 if (!yaml_parser_unroll_indent(parser, -1))
1411 return 0;
1412
1413 /* Reset simple keys. */
1414
1415 if (!yaml_parser_remove_simple_key(parser))
1416 return 0;
1417
1418 parser->simple_key_allowed = 0;
1419
1420 /* Consume the token. */
1421
1422 start_mark = parser->mark;
1423
1424 SKIP(parser);
1425 SKIP(parser);
1426 SKIP(parser);
1427
1428 end_mark = parser->mark;
1429
1430 /* Create the DOCUMENT-START or DOCUMENT-END token. */
1431
1432 TOKEN_INIT(token, type, start_mark, end_mark);
1433
1434 /* Append the token to the queue. */
1435
1436 if (!ENQUEUE(parser, parser->tokens, token))
1437 return 0;
1438
1439 return 1;
1440 }
1441
1442 /*
1443 * Produce the FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
1444 */
1445
1446 static int
1447 yaml_parser_fetch_flow_collection_start(yaml_parser_t *parser,
1448 yaml_token_type_t type)
1449 {
1450 yaml_mark_t start_mark, end_mark;
1451 yaml_token_t token;
1452
1453 /* The indicators '[' and '{' may start a simple key. */
1454
1455 if (!yaml_parser_save_simple_key(parser))
1456 return 0;
1457
1458 /* Increase the flow level. */
1459
1460 if (!yaml_parser_increase_flow_level(parser))
1461 return 0;
1462
1463 /* A simple key may follow the indicators '[' and '{'. */
1464
1465 parser->simple_key_allowed = 1;
1466
1467 /* Consume the token. */
1468
1469 start_mark = parser->mark;
1470 SKIP(parser);
1471 end_mark = parser->mark;
1472
1473 /* Create the FLOW-SEQUENCE-START of FLOW-MAPPING-START token. */
1474
1475 TOKEN_INIT(token, type, start_mark, end_mark);
1476
1477 /* Append the token to the queue. */
1478
1479 if (!ENQUEUE(parser, parser->tokens, token))
1480 return 0;
1481
1482 return 1;
1483 }
1484
1485 /*
1486 * Produce the FLOW-SEQUENCE-END or FLOW-MAPPING-END token.
1487 */
1488
1489 static int
1490 yaml_parser_fetch_flow_collection_end(yaml_parser_t *parser,
1491 yaml_token_type_t type)
1492 {
1493 yaml_mark_t start_mark, end_mark;
1494 yaml_token_t token;
1495
1496 /* Reset any potential simple key on the current flow level. */
1497
1498 if (!yaml_parser_remove_simple_key(parser))
1499 return 0;
1500
1501 /* Decrease the flow level. */
1502
1503 if (!yaml_parser_decrease_flow_level(parser))
1504 return 0;
1505
1506 /* No simple keys after the indicators ']' and '}'. */
1507
1508 parser->simple_key_allowed = 0;
1509
1510 /* Consume the token. */
1511
1512 start_mark = parser->mark;
1513 SKIP(parser);
1514 end_mark = parser->mark;
1515
1516 /* Create the FLOW-SEQUENCE-END of FLOW-MAPPING-END token. */
1517
1518 TOKEN_INIT(token, type, start_mark, end_mark);
1519
1520 /* Append the token to the queue. */
1521
1522 if (!ENQUEUE(parser, parser->tokens, token))
1523 return 0;
1524
1525 return 1;
1526 }
1527
1528 /*
1529 * Produce the FLOW-ENTRY token.
1530 */
1531
1532 static int
1533 yaml_parser_fetch_flow_entry(yaml_parser_t *parser)
1534 {
1535 yaml_mark_t start_mark, end_mark;
1536 yaml_token_t token;
1537
1538 /* Reset any potential simple keys on the current flow level. */
1539
1540 if (!yaml_parser_remove_simple_key(parser))
1541 return 0;
1542
1543 /* Simple keys are allowed after ','. */
1544
1545 parser->simple_key_allowed = 1;
1546
1547 /* Consume the token. */
1548
1549 start_mark = parser->mark;
1550 SKIP(parser);
1551 end_mark = parser->mark;
1552
1553 /* Create the FLOW-ENTRY token and append it to the queue. */
1554
1555 TOKEN_INIT(token, YAML_FLOW_ENTRY_TOKEN, start_mark, end_mark);
1556
1557 if (!ENQUEUE(parser, parser->tokens, token))
1558 return 0;
1559
1560 return 1;
1561 }
1562
1563 /*
1564 * Produce the BLOCK-ENTRY token.
1565 */
1566
1567 static int
1568 yaml_parser_fetch_block_entry(yaml_parser_t *parser)
1569 {
1570 yaml_mark_t start_mark, end_mark;
1571 yaml_token_t token;
1572
1573 /* Check if the scanner is in the block context. */
1574
1575 if (!parser->flow_level)
1576 {
1577 /* Check if we are allowed to start a new entry. */
1578
1579 if (!parser->simple_key_allowed) {
1580 return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
1581 "block sequence entries are not allowed in this context");
1582 }
1583
1584 /* Add the BLOCK-SEQUENCE-START token if needed. */
1585
1586 if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
1587 YAML_BLOCK_SEQUENCE_START_TOKEN, parser->mark))
1588 return 0;
1589 }
1590 else
1591 {
1592 /*
1593 * It is an error for the '-' indicator to occur in the flow context,
1594 * but we let the Parser detect and report about it because the Parser
1595 * is able to point to the context.
1596 */
1597 }
1598
1599 /* Reset any potential simple keys on the current flow level. */
1600
1601 if (!yaml_parser_remove_simple_key(parser))
1602 return 0;
1603
1604 /* Simple keys are allowed after '-'. */
1605
1606 parser->simple_key_allowed = 1;
1607
1608 /* Consume the token. */
1609
1610 start_mark = parser->mark;
1611 SKIP(parser);
1612 end_mark = parser->mark;
1613
1614 /* Create the BLOCK-ENTRY token and append it to the queue. */
1615
1616 TOKEN_INIT(token, YAML_BLOCK_ENTRY_TOKEN, start_mark, end_mark);
1617
1618 if (!ENQUEUE(parser, parser->tokens, token))
1619 return 0;
1620
1621 return 1;
1622 }
1623
1624 /*
1625 * Produce the KEY token.
1626 */
1627
1628 static int
1629 yaml_parser_fetch_key(yaml_parser_t *parser)
1630 {
1631 yaml_mark_t start_mark, end_mark;
1632 yaml_token_t token;
1633
1634 /* In the block context, additional checks are required. */
1635
1636 if (!parser->flow_level)
1637 {
1638 /* Check if we are allowed to start a new key (not nessesary simple). */
1639
1640 if (!parser->simple_key_allowed) {
1641 return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
1642 "mapping keys are not allowed in this context");
1643 }
1644
1645 /* Add the BLOCK-MAPPING-START token if needed. */
1646
1647 if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
1648 YAML_BLOCK_MAPPING_START_TOKEN, parser->mark))
1649 return 0;
1650 }
1651
1652 /* Reset any potential simple keys on the current flow level. */
1653
1654 if (!yaml_parser_remove_simple_key(parser))
1655 return 0;
1656
1657 /* Simple keys are allowed after '?' in the block context. */
1658
1659 parser->simple_key_allowed = (!parser->flow_level);
1660
1661 /* Consume the token. */
1662
1663 start_mark = parser->mark;
1664 SKIP(parser);
1665 end_mark = parser->mark;
1666
1667 /* Create the KEY token and append it to the queue. */
1668
1669 TOKEN_INIT(token, YAML_KEY_TOKEN, start_mark, end_mark);
1670
1671 if (!ENQUEUE(parser, parser->tokens, token))
1672 return 0;
1673
1674 return 1;
1675 }
1676
1677 /*
1678 * Produce the VALUE token.
1679 */
1680
1681 static int
1682 yaml_parser_fetch_value(yaml_parser_t *parser)
1683 {
1684 yaml_mark_t start_mark, end_mark;
1685 yaml_token_t token;
1686 yaml_simple_key_t *simple_key = parser->simple_keys.top-1;
1687
1688 /* Have we found a simple key? */
1689
1690 if (simple_key->possible)
1691 {
1692
1693 /* Create the KEY token and insert it into the queue. */
1694
1695 TOKEN_INIT(token, YAML_KEY_TOKEN, simple_key->mark, simple_key->mark);
1696
1697 if (!QUEUE_INSERT(parser, parser->tokens,
1698 simple_key->token_number - parser->tokens_parsed, token))
1699 return 0;
1700
1701 /* In the block context, we may need to add the BLOCK-MAPPING-START token. */
1702
1703 if (!yaml_parser_roll_indent(parser, simple_key->mark.column,
1704 simple_key->token_number,
1705 YAML_BLOCK_MAPPING_START_TOKEN, simple_key->mark))
1706 return 0;
1707
1708 /* Remove the simple key. */
1709
1710 simple_key->possible = 0;
1711
1712 /* A simple key cannot follow another simple key. */
1713
1714 parser->simple_key_allowed = 0;
1715 }
1716 else
1717 {
1718 /* The ':' indicator follows a complex key. */
1719
1720 /* In the block context, extra checks are required. */
1721
1722 if (!parser->flow_level)
1723 {
1724 /* Check if we are allowed to start a complex value. */
1725
1726 if (!parser->simple_key_allowed) {
1727 return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
1728 "mapping values are not allowed in this context");
1729 }
1730
1731 /* Add the BLOCK-MAPPING-START token if needed. */
1732
1733 if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
1734 YAML_BLOCK_MAPPING_START_TOKEN, parser->mark))
1735 return 0;
1736 }
1737
1738 /* Simple keys after ':' are allowed in the block context. */
1739
1740 parser->simple_key_allowed = (!parser->flow_level);
1741 }
1742
1743 /* Consume the token. */
1744
1745 start_mark = parser->mark;
1746 SKIP(parser);
1747 end_mark = parser->mark;
1748
1749 /* Create the VALUE token and append it to the queue. */
1750
1751 TOKEN_INIT(token, YAML_VALUE_TOKEN, start_mark, end_mark);
1752
1753 if (!ENQUEUE(parser, parser->tokens, token))
1754 return 0;
1755
1756 return 1;
1757 }
1758
1759 /*
1760 * Produce the ALIAS or ANCHOR token.
1761 */
1762
1763 static int
1764 yaml_parser_fetch_anchor(yaml_parser_t *parser, yaml_token_type_t type)
1765 {
1766 yaml_token_t token;
1767
1768 /* An anchor or an alias could be a simple key. */
1769
1770 if (!yaml_parser_save_simple_key(parser))
1771 return 0;
1772
1773 /* A simple key cannot follow an anchor or an alias. */
1774
1775 parser->simple_key_allowed = 0;
1776
1777 /* Create the ALIAS or ANCHOR token and append it to the queue. */
1778
1779 if (!yaml_parser_scan_anchor(parser, &token, type))
1780 return 0;
1781
1782 if (!ENQUEUE(parser, parser->tokens, token)) {
1783 yaml_token_delete(&token);
1784 return 0;
1785 }
1786 return 1;
1787 }
1788
1789 /*
1790 * Produce the TAG token.
1791 */
1792
1793 static int
1794 yaml_parser_fetch_tag(yaml_parser_t *parser)
1795 {
1796 yaml_token_t token;
1797
1798 /* A tag could be a simple key. */
1799
1800 if (!yaml_parser_save_simple_key(parser))
1801 return 0;
1802
1803 /* A simple key cannot follow a tag. */
1804
1805 parser->simple_key_allowed = 0;
1806
1807 /* Create the TAG token and append it to the queue. */
1808
1809 if (!yaml_parser_scan_tag(parser, &token))
1810 return 0;
1811
1812 if (!ENQUEUE(parser, parser->tokens, token)) {
1813 yaml_token_delete(&token);
1814 return 0;
1815 }
1816
1817 return 1;
1818 }
1819
1820 /*
1821 * Produce the SCALAR(...,literal) or SCALAR(...,folded) tokens.
1822 */
1823
1824 static int
1825 yaml_parser_fetch_block_scalar(yaml_parser_t *parser, int literal)
1826 {
1827 yaml_token_t token;
1828
1829 /* Remove any potential simple keys. */
1830
1831 if (!yaml_parser_remove_simple_key(parser))
1832 return 0;
1833
1834 /* A simple key may follow a block scalar. */
1835
1836 parser->simple_key_allowed = 1;
1837
1838 /* Create the SCALAR token and append it to the queue. */
1839
1840 if (!yaml_parser_scan_block_scalar(parser, &token, literal))
1841 return 0;
1842
1843 if (!ENQUEUE(parser, parser->tokens, token)) {
1844 yaml_token_delete(&token);
1845 return 0;
1846 }
1847
1848 return 1;
1849 }
1850
1851 /*
1852 * Produce the SCALAR(...,single-quoted) or SCALAR(...,double-quoted) tokens.
1853 */
1854
1855 static int
1856 yaml_parser_fetch_flow_scalar(yaml_parser_t *parser, int single)
1857 {
1858 yaml_token_t token;
1859
1860 /* A plain scalar could be a simple key. */
1861
1862 if (!yaml_parser_save_simple_key(parser))
1863 return 0;
1864
1865 /* A simple key cannot follow a flow scalar. */
1866
1867 parser->simple_key_allowed = 0;
1868
1869 /* Create the SCALAR token and append it to the queue. */
1870
1871 if (!yaml_parser_scan_flow_scalar(parser, &token, single))
1872 return 0;
1873
1874 if (!ENQUEUE(parser, parser->tokens, token)) {
1875 yaml_token_delete(&token);
1876 return 0;
1877 }
1878
1879 return 1;
1880 }
1881
1882 /*
1883 * Produce the SCALAR(...,plain) token.
1884 */
1885
1886 static int
1887 yaml_parser_fetch_plain_scalar(yaml_parser_t *parser)
1888 {
1889 yaml_token_t token;
1890
1891 /* A plain scalar could be a simple key. */
1892
1893 if (!yaml_parser_save_simple_key(parser))
1894 return 0;
1895
1896 /* A simple key cannot follow a flow scalar. */
1897
1898 parser->simple_key_allowed = 0;
1899
1900 /* Create the SCALAR token and append it to the queue. */
1901
1902 if (!yaml_parser_scan_plain_scalar(parser, &token))
1903 return 0;
1904
1905 if (!ENQUEUE(parser, parser->tokens, token)) {
1906 yaml_token_delete(&token);
1907 return 0;
1908 }
1909
1910 return 1;
1911 }
1912
1913 /*
1914 * Eat whitespaces and comments until the next token is found.
1915 */
1916
1917 static int
1918 yaml_parser_scan_to_next_token(yaml_parser_t *parser)
1919 {
1920 /* Until the next token is not found. */
1921
1922 while (1)
1923 {
1924 /* Allow the BOM mark to start a line. */
1925
1926 if (!CACHE(parser, 1)) return 0;
1927
1928 if (parser->mark.column == 0 && IS_BOM(parser->buffer))
1929 SKIP(parser);
1930
1931 /*
1932 * Eat whitespaces.
1933 *
1934 * Tabs are allowed:
1935 *
1936 * - in the flow context;
1937 * - in the block context, but not at the beginning of the line or
1938 * after '-', '?', or ':' (complex value).
1939 */
1940
1941 if (!CACHE(parser, 1)) return 0;
1942
1943 while (CHECK(parser->buffer,' ') ||
1944 ((parser->flow_level || !parser->simple_key_allowed) &&
1945 CHECK(parser->buffer, '\t'))) {
1946 SKIP(parser);
1947 if (!CACHE(parser, 1)) return 0;
1948 }
1949
1950 /* Eat a comment until a line break. */
1951
1952 if (CHECK(parser->buffer, '#')) {
1953 while (!IS_BREAKZ(parser->buffer)) {
1954 SKIP(parser);
1955 if (!CACHE(parser, 1)) return 0;
1956 }
1957 }
1958
1959 /* If it is a line break, eat it. */
1960
1961 if (IS_BREAK(parser->buffer))
1962 {
1963 if (!CACHE(parser, 2)) return 0;
1964 SKIP_LINE(parser);
1965
1966 /* In the block context, a new line may start a simple key. */
1967
1968 if (!parser->flow_level) {
1969 parser->simple_key_allowed = 1;
1970 }
1971 }
1972 else
1973 {
1974 /* We have found a token. */
1975
1976 break;
1977 }
1978 }
1979
1980 return 1;
1981 }
1982
1983 /*
1984 * Scan a YAML-DIRECTIVE or TAG-DIRECTIVE token.
1985 *
1986 * Scope:
1987 * %YAML 1.1 # a comment \n
1988 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1989 * %TAG !yaml! tag:yaml.org,2002: \n
1990 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1991 */
1992
1993 int
1994 yaml_parser_scan_directive(yaml_parser_t *parser, yaml_token_t *token)
1995 {
1996 yaml_mark_t start_mark, end_mark;
1997 yaml_char_t *name = NULL;
1998 int major, minor;
1999 yaml_char_t *handle = NULL, *prefix = NULL;
2000
2001 /* Eat '%'. */
2002
2003 start_mark = parser->mark;
2004
2005 SKIP(parser);
2006
2007 /* Scan the directive name. */
2008
2009 if (!yaml_parser_scan_directive_name(parser, start_mark, &name))
2010 goto error;
2011
2012 /* Is it a YAML directive? */
2013
2014 if (strcmp((char *)name, "YAML") == 0)
2015 {
2016 /* Scan the VERSION directive value. */
2017
2018 if (!yaml_parser_scan_version_directive_value(parser, start_mark,
2019 &major, &minor))
2020 goto error;
2021
2022 end_mark = parser->mark;
2023
2024 /* Create a VERSION-DIRECTIVE token. */
2025
2026 VERSION_DIRECTIVE_TOKEN_INIT(*token, major, minor,
2027 start_mark, end_mark);
2028 }
2029
2030 /* Is it a TAG directive? */
2031
2032 else if (strcmp((char *)name, "TAG") == 0)
2033 {
2034 /* Scan the TAG directive value. */
2035
2036 if (!yaml_parser_scan_tag_directive_value(parser, start_mark,
2037 &handle, &prefix))
2038 goto error;
2039
2040 end_mark = parser->mark;
2041
2042 /* Create a TAG-DIRECTIVE token. */
2043
2044 TAG_DIRECTIVE_TOKEN_INIT(*token, handle, prefix,
2045 start_mark, end_mark);
2046 }
2047
2048 /* Unknown directive. */
2049
2050 else
2051 {
2052 yaml_parser_set_scanner_error(parser, "while scanning a directive",
2053 start_mark, "found uknown directive name");
2054 goto error;
2055 }
2056
2057 /* Eat the rest of the line including any comments. */
2058
2059 if (!CACHE(parser, 1)) goto error;
2060
2061 while (IS_BLANK(parser->buffer)) {
2062 SKIP(parser);
2063 if (!CACHE(parser, 1)) goto error;
2064 }
2065
2066 if (CHECK(parser->buffer, '#')) {
2067 while (!IS_BREAKZ(parser->buffer)) {
2068 SKIP(parser);
2069 if (!CACHE(parser, 1)) goto error;
2070 }
2071 }
2072
2073 /* Check if we are at the end of the line. */
2074
2075 if (!IS_BREAKZ(parser->buffer)) {
2076 yaml_parser_set_scanner_error(parser, "while scanning a directive",
2077 start_mark, "did not find expected comment or line break");
2078 goto error;
2079 }
2080
2081 /* Eat a line break. */
2082
2083 if (IS_BREAK(parser->buffer)) {
2084 if (!CACHE(parser, 2)) goto error;
2085 SKIP_LINE(parser);
2086 }
2087
2088 yaml_free(name);
2089
2090 return 1;
2091
2092 error:
2093 yaml_free(prefix);
2094 yaml_free(handle);
2095 yaml_free(name);
2096 return 0;
2097 }
2098
2099 /*
2100 * Scan the directive name.
2101 *
2102 * Scope:
2103 * %YAML 1.1 # a comment \n
2104 * ^^^^
2105 * %TAG !yaml! tag:yaml.org,2002: \n
2106 * ^^^
2107 */
2108
2109 static int
2110 yaml_parser_scan_directive_name(yaml_parser_t *parser,
2111 yaml_mark_t start_mark, yaml_char_t **name)
2112 {
2113 yaml_string_t string = NULL_STRING;
2114
2115 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
2116
2117 /* Consume the directive name. */
2118
2119 if (!CACHE(parser, 1)) goto error;
2120
2121 while (IS_ALPHA(parser->buffer))
2122 {
2123 if (!READ(parser, string)) goto error;
2124 if (!CACHE(parser, 1)) goto error;
2125 }
2126
2127 /* Check if the name is empty. */
2128
2129 if (string.start == string.pointer) {
2130 yaml_parser_set_scanner_error(parser, "while scanning a directive",
2131 start_mark, "could not find expected directive name");
2132 goto error;
2133 }
2134
2135 /* Check for an blank character after the name. */
2136
2137 if (!IS_BLANKZ(parser->buffer)) {
2138 yaml_parser_set_scanner_error(parser, "while scanning a directive",
2139 start_mark, "found unexpected non-alphabetical character");
2140 goto error;
2141 }
2142
2143 *name = string.start;
2144
2145 return 1;
2146
2147 error:
2148 STRING_DEL(parser, string);
2149 return 0;
2150 }
2151
2152 /*
2153 * Scan the value of VERSION-DIRECTIVE.
2154 *
2155 * Scope:
2156 * %YAML 1.1 # a comment \n
2157 * ^^^^^^
2158 */
2159
2160 static int
2161 yaml_parser_scan_version_directive_value(yaml_parser_t *parser,
2162 yaml_mark_t start_mark, int *major, int *minor)
2163 {
2164 /* Eat whitespaces. */
2165
2166 if (!CACHE(parser, 1)) return 0;
2167
2168 while (IS_BLANK(parser->buffer)) {
2169 SKIP(parser);
2170 if (!CACHE(parser, 1)) return 0;
2171 }
2172
2173 /* Consume the major version number. */
2174
2175 if (!yaml_parser_scan_version_directive_number(parser, start_mark, major))
2176 return 0;
2177
2178 /* Eat '.'. */
2179
2180 if (!CHECK(parser->buffer, '.')) {
2181 return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
2182 start_mark, "did not find expected digit or '.' character");
2183 }
2184
2185 SKIP(parser);
2186
2187 /* Consume the minor version number. */
2188
2189 if (!yaml_parser_scan_version_directive_number(parser, start_mark, minor))
2190 return 0;
2191
2192 return 1;
2193 }
2194
2195 #define MAX_NUMBER_LENGTH 9
2196
2197 /*
2198 * Scan the version number of VERSION-DIRECTIVE.
2199 *
2200 * Scope:
2201 * %YAML 1.1 # a comment \n
2202 * ^
2203 * %YAML 1.1 # a comment \n
2204 * ^
2205 */
2206
2207 static int
2208 yaml_parser_scan_version_directive_number(yaml_parser_t *parser,
2209 yaml_mark_t start_mark, int *number)
2210 {
2211 int value = 0;
2212 size_t length = 0;
2213
2214 /* Repeat while the next character is digit. */
2215
2216 if (!CACHE(parser, 1)) return 0;
2217
2218 while (IS_DIGIT(parser->buffer))
2219 {
2220 /* Check if the number is too long. */
2221
2222 if (++length > MAX_NUMBER_LENGTH) {
2223 return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
2224 start_mark, "found extremely long version number");
2225 }
2226
2227 value = value*10 + AS_DIGIT(parser->buffer);
2228
2229 SKIP(parser);
2230
2231 if (!CACHE(parser, 1)) return 0;
2232 }
2233
2234 /* Check if the number was present. */
2235
2236 if (!length) {
2237 return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
2238 start_mark, "did not find expected version number");
2239 }
2240
2241 *number = value;
2242
2243 return 1;
2244 }
2245
2246 /*
2247 * Scan the value of a TAG-DIRECTIVE token.
2248 *
2249 * Scope:
2250 * %TAG !yaml! tag:yaml.org,2002: \n
2251 * ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2252 */
2253
2254 static int
2255 yaml_parser_scan_tag_directive_value(yaml_parser_t *parser,
2256 yaml_mark_t start_mark, yaml_char_t **handle, yaml_char_t **prefix)
2257 {
2258 yaml_char_t *handle_value = NULL;
2259 yaml_char_t *prefix_value = NULL;
2260
2261 /* Eat whitespaces. */
2262
2263 if (!CACHE(parser, 1)) goto error;
2264
2265 while (IS_BLANK(parser->buffer)) {
2266 SKIP(parser);
2267 if (!CACHE(parser, 1)) goto error;
2268 }
2269
2270 /* Scan a handle. */
2271
2272 if (!yaml_parser_scan_tag_handle(parser, 1, start_mark, &handle_value))
2273 goto error;
2274
2275 /* Expect a whitespace. */
2276
2277 if (!CACHE(parser, 1)) goto error;
2278
2279 if (!IS_BLANK(parser->buffer)) {
2280 yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
2281 start_mark, "did not find expected whitespace");
2282 goto error;
2283 }
2284
2285 /* Eat whitespaces. */
2286
2287 while (IS_BLANK(parser->buffer)) {
2288 SKIP(parser);
2289 if (!CACHE(parser, 1)) goto error;
2290 }
2291
2292 /* Scan a prefix. */
2293
2294 if (!yaml_parser_scan_tag_uri(parser, 1, NULL, start_mark, &prefix_value))
2295 goto error;
2296
2297 /* Expect a whitespace or line break. */
2298
2299 if (!CACHE(parser, 1)) goto error;
2300
2301 if (!IS_BLANKZ(parser->buffer)) {
2302 yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
2303 start_mark, "did not find expected whitespace or line break");
2304 goto error;
2305 }
2306
2307 *handle = handle_value;
2308 *prefix = prefix_value;
2309
2310 return 1;
2311
2312 error:
2313 yaml_free(handle_value);
2314 yaml_free(prefix_value);
2315 return 0;
2316 }
2317
2318 static int
2319 yaml_parser_scan_anchor(yaml_parser_t *parser, yaml_token_t *token,
2320 yaml_token_type_t type)
2321 {
2322 int length = 0;
2323 yaml_mark_t start_mark, end_mark;
2324 yaml_string_t string = NULL_STRING;
2325
2326 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
2327
2328 /* Eat the indicator character. */
2329
2330 start_mark = parser->mark;
2331
2332 SKIP(parser);
2333
2334 /* Consume the value. */
2335
2336 if (!CACHE(parser, 1)) goto error;
2337
2338 while (IS_ALPHA(parser->buffer)) {
2339 if (!READ(parser, string)) goto error;
2340 if (!CACHE(parser, 1)) goto error;
2341 length ++;
2342 }
2343
2344 end_mark = parser->mark;
2345
2346 /*
2347 * Check if length of the anchor is greater than 0 and it is followed by
2348 * a whitespace character or one of the indicators:
2349 *
2350 * '?', ':', ',', ']', '}', '%', '@', '`'.
2351 */
2352
2353 if (!length || !(IS_BLANKZ(parser->buffer) || CHECK(parser->buffer, '?')
2354 || CHECK(parser->buffer, ':') || CHECK(parser->buffer, ',')
2355 || CHECK(parser->buffer, ']') || CHECK(parser->buffer, '}')
2356 || CHECK(parser->buffer, '%') || CHECK(parser->buffer, '@')
2357 || CHECK(parser->buffer, '`'))) {
2358 yaml_parser_set_scanner_error(parser, type == YAML_ANCHOR_TOKEN ?
2359 "while scanning an anchor" : "while scanning an alias", start_mark,
2360 "did not find expected alphabetic or numeric character");
2361 goto error;
2362 }
2363
2364 /* Create a token. */
2365
2366 if (type == YAML_ANCHOR_TOKEN) {
2367 ANCHOR_TOKEN_INIT(*token, string.start, start_mark, end_mark);
2368 }
2369 else {
2370 ALIAS_TOKEN_INIT(*token, string.start, start_mark, end_mark);
2371 }
2372
2373 return 1;
2374
2375 error:
2376 STRING_DEL(parser, string);
2377 return 0;
2378 }
2379
2380 /*
2381 * Scan a TAG token.
2382 */
2383
2384 static int
2385 yaml_parser_scan_tag(yaml_parser_t *parser, yaml_token_t *token)
2386 {
2387 yaml_char_t *handle = NULL;
2388 yaml_char_t *suffix = NULL;
2389 yaml_mark_t start_mark, end_mark;
2390
2391 start_mark = parser->mark;
2392
2393 /* Check if the tag is in the canonical form. */
2394
2395 if (!CACHE(parser, 2)) goto error;
2396
2397 if (CHECK_AT(parser->buffer, '<', 1))
2398 {
2399 /* Set the handle to '' */
2400
2401 handle = yaml_malloc(1);
2402 if (!handle) goto error;
2403 handle[0] = '\0';
2404
2405 /* Eat '!<' */
2406
2407 SKIP(parser);
2408 SKIP(parser);
2409
2410 /* Consume the tag value. */
2411
2412 if (!yaml_parser_scan_tag_uri(parser, 0, NULL, start_mark, &suffix))
2413 goto error;
2414
2415 /* Check for '>' and eat it. */
2416
2417 if (!CHECK(parser->buffer, '>')) {
2418 yaml_parser_set_scanner_error(parser, "while scanning a tag",
2419 start_mark, "did not find the expected '>'");
2420 goto error;
2421 }
2422
2423 SKIP(parser);
2424 }
2425 else
2426 {
2427 /* The tag has either the '!suffix' or the '!handle!suffix' form. */
2428
2429 /* First, try to scan a handle. */
2430
2431 if (!yaml_parser_scan_tag_handle(parser, 0, start_mark, &handle))
2432 goto error;
2433
2434 /* Check if it is, indeed, handle. */
2435
2436 if (handle[0] == '!' && handle[1] != '\0' && handle[strlen((char *)handle)-1] == '!')
2437 {
2438 /* Scan the suffix now. */
2439
2440 if (!yaml_parser_scan_tag_uri(parser, 0, NULL, start_mark, &suffix))
2441 goto error;
2442 }
2443 else
2444 {
2445 /* It wasn't a handle after all. Scan the rest of the tag. */
2446
2447 if (!yaml_parser_scan_tag_uri(parser, 0, handle, start_mark, &suffix))
2448 goto error;
2449
2450 /* Set the handle to '!'. */
2451
2452 yaml_free(handle);
2453 handle = yaml_malloc(2);
2454 if (!handle) goto error;
2455 handle[0] = '!';
2456 handle[1] = '\0';
2457
2458 /*
2459 * A special case: the '!' tag. Set the handle to '' and the
2460 * suffix to '!'.
2461 */
2462
2463 if (suffix[0] == '\0') {
2464 yaml_char_t *tmp = handle;
2465 handle = suffix;
2466 suffix = tmp;
2467 }
2468 }
2469 }
2470
2471 /* Check the character which ends the tag. */
2472
2473 if (!CACHE(parser, 1)) goto error;
2474
2475 if (!IS_BLANKZ(parser->buffer)) {
2476 yaml_parser_set_scanner_error(parser, "while scanning a tag",
2477 start_mark, "did not find expected whitespace or line break");
2478 goto error;
2479 }
2480
2481 end_mark = parser->mark;
2482
2483 /* Create a token. */
2484
2485 TAG_TOKEN_INIT(*token, handle, suffix, start_mark, end_mark);
2486
2487 return 1;
2488
2489 error:
2490 yaml_free(handle);
2491 yaml_free(suffix);
2492 return 0;
2493 }
2494
2495 /*
2496 * Scan a tag handle.
2497 */
2498
2499 static int
2500 yaml_parser_scan_tag_handle(yaml_parser_t *parser, int directive,
2501 yaml_mark_t start_mark, yaml_char_t **handle)
2502 {
2503 yaml_string_t string = NULL_STRING;
2504
2505 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
2506
2507 /* Check the initial '!' character. */
2508
2509 if (!CACHE(parser, 1)) goto error;
2510
2511 if (!CHECK(parser->buffer, '!')) {
2512 yaml_parser_set_scanner_error(parser, directive ?
2513 "while scanning a tag directive" : "while scanning a tag",
2514 start_mark, "did not find expected '!'");
2515 goto error;
2516 }
2517
2518 /* Copy the '!' character. */
2519
2520 if (!READ(parser, string)) goto error;
2521
2522 /* Copy all subsequent alphabetical and numerical characters. */
2523
2524 if (!CACHE(parser, 1)) goto error;
2525
2526 while (IS_ALPHA(parser->buffer))
2527 {
2528 if (!READ(parser, string)) goto error;
2529 if (!CACHE(parser, 1)) goto error;
2530 }
2531
2532 /* Check if the trailing character is '!' and copy it. */
2533
2534 if (CHECK(parser->buffer, '!'))
2535 {
2536 if (!READ(parser, string)) goto error;
2537 }
2538 else
2539 {
2540 /*
2541 * It's either the '!' tag or not really a tag handle. If it's a %TAG
2542 * directive, it's an error. If it's a tag token, it must be a part of
2543 * URI.
2544 */
2545
2546 if (directive && !(string.start[0] == '!' && string.start[1] == '\0')) {
2547 yaml_parser_set_scanner_error(parser, "while parsing a tag directive",
2548 start_mark, "did not find expected '!'");
2549 goto error;
2550 }
2551 }
2552
2553 *handle = string.start;
2554
2555 return 1;
2556
2557 error:
2558 STRING_DEL(parser, string);
2559 return 0;
2560 }
2561
2562 /*
2563 * Scan a tag.
2564 */
2565
2566 static int
2567 yaml_parser_scan_tag_uri(yaml_parser_t *parser, int directive,
2568 yaml_char_t *head, yaml_mark_t start_mark, yaml_char_t **uri)
2569 {
2570 size_t length = head ? strlen((char *)head) : 0;
2571 yaml_string_t string = NULL_STRING;
2572
2573 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
2574
2575 /* Resize the string to include the head. */
2576
2577 while (string.end - string.start <= (int)length) {
2578 if (!yaml_string_extend(&string.start, &string.pointer, &string.end)) {
2579 parser->error = YAML_MEMORY_ERROR;
2580 goto error;
2581 }
2582 }
2583
2584 /*
2585 * Copy the head if needed.
2586 *
2587 * Note that we don't copy the leading '!' character.
2588 */
2589
2590 if (length > 1) {
2591 memcpy(string.start, head+1, length-1);
2592 string.pointer += length-1;
2593 }
2594
2595 /* Scan the tag. */
2596
2597 if (!CACHE(parser, 1)) goto error;
2598
2599 /*
2600 * The set of characters that may appear in URI is as follows:
2601 *
2602 * '0'-'9', 'A'-'Z', 'a'-'z', '_', '-', ';', '/', '?', ':', '@', '&',
2603 * '=', '+', '$', ',', '.', '!', '~', '*', '\'', '(', ')', '[', ']',
2604 * '%'.
2605 */
2606
2607 while (IS_ALPHA(parser->buffer) || CHECK(parser->buffer, ';')
2608 || CHECK(parser->buffer, '/') || CHECK(parser->buffer, '?')
2609 || CHECK(parser->buffer, ':') || CHECK(parser->buffer, '@')
2610 || CHECK(parser->buffer, '&') || CHECK(parser->buffer, '=')
2611 || CHECK(parser->buffer, '+') || CHECK(parser->buffer, '$')
2612 || CHECK(parser->buffer, ',') || CHECK(parser->buffer, '.')
2613 || CHECK(parser->buffer, '!') || CHECK(parser->buffer, '~')
2614 || CHECK(parser->buffer, '*') || CHECK(parser->buffer, '\'')
2615 || CHECK(parser->buffer, '(') || CHECK(parser->buffer, ')')
2616 || CHECK(parser->buffer, '[') || CHECK(parser->buffer, ']')
2617 || CHECK(parser->buffer, '%'))
2618 {
2619 /* Check if it is a URI-escape sequence. */
2620
2621 if (CHECK(parser->buffer, '%')) {
2622 if (!yaml_parser_scan_uri_escapes(parser,
2623 directive, start_mark, &string)) goto error;
2624 }
2625 else {
2626 if (!READ(parser, string)) goto error;
2627 }
2628
2629 length ++;
2630 if (!CACHE(parser, 1)) goto error;
2631 }
2632
2633 /* Check if the tag is non-empty. */
2634
2635 if (!length) {
2636 if (!STRING_EXTEND(parser, string))
2637 goto error;
2638
2639 yaml_parser_set_scanner_error(parser, directive ?
2640 "while parsing a %TAG directive" : "while parsing a tag",
2641 start_mark, "did not find expected tag URI");
2642 goto error;
2643 }
2644
2645 *uri = string.start;
2646
2647 return 1;
2648
2649 error:
2650 STRING_DEL(parser, string);
2651 return 0;
2652 }
2653
2654 /*
2655 * Decode an URI-escape sequence corresponding to a single UTF-8 character.
2656 */
2657
2658 static int
2659 yaml_parser_scan_uri_escapes(yaml_parser_t *parser, int directive,
2660 yaml_mark_t start_mark, yaml_string_t *string)
2661 {
2662 int width = 0;
2663
2664 /* Decode the required number of characters. */
2665
2666 do {
2667
2668 unsigned char octet = 0;
2669
2670 /* Check for a URI-escaped octet. */
2671
2672 if (!CACHE(parser, 3)) return 0;
2673
2674 if (!(CHECK(parser->buffer, '%')
2675 && IS_HEX_AT(parser->buffer, 1)
2676 && IS_HEX_AT(parser->buffer, 2))) {
2677 return yaml_parser_set_scanner_error(parser, directive ?
2678 "while parsing a %TAG directive" : "while parsing a tag",
2679 start_mark, "did not find URI escaped octet");
2680 }
2681
2682 /* Get the octet. */
2683
2684 octet = (AS_HEX_AT(parser->buffer, 1) << 4) + AS_HEX_AT(parser->buffer, 2);
2685
2686 /* If it is the leading octet, determine the length of the UTF-8 sequence. */
2687
2688 if (!width)
2689 {
2690 width = (octet & 0x80) == 0x00 ? 1 :
2691 (octet & 0xE0) == 0xC0 ? 2 :
2692 (octet & 0xF0) == 0xE0 ? 3 :
2693 (octet & 0xF8) == 0xF0 ? 4 : 0;
2694 if (!width) {
2695 return yaml_parser_set_scanner_error(parser, directive ?
2696 "while parsing a %TAG directive" : "while parsing a tag",
2697 start_mark, "found an incorrect leading UTF-8 octet");
2698 }
2699 }
2700 else
2701 {
2702 /* Check if the trailing octet is correct. */
2703
2704 if ((octet & 0xC0) != 0x80) {
2705 return yaml_parser_set_scanner_error(parser, directive ?
2706 "while parsing a %TAG directive" : "while parsing a tag",
2707 start_mark, "found an incorrect trailing UTF-8 octet");
2708 }
2709 }
2710
2711 /* Copy the octet and move the pointers. */
2712
2713 *(string->pointer++) = octet;
2714 SKIP(parser);
2715 SKIP(parser);
2716 SKIP(parser);
2717
2718 } while (--width);
2719
2720 return 1;
2721 }
2722
2723 /*
2724 * Scan a block scalar.
2725 */
2726
2727 static int
2728 yaml_parser_scan_block_scalar(yaml_parser_t *parser, yaml_token_t *token,
2729 int literal)
2730 {
2731 yaml_mark_t start_mark;
2732 yaml_mark_t end_mark;
2733 yaml_string_t string = NULL_STRING;
2734 yaml_string_t leading_break = NULL_STRING;
2735 yaml_string_t trailing_breaks = NULL_STRING;
2736 int chomping = 0;
2737 int increment = 0;
2738 int indent = 0;
2739 int leading_blank = 0;
2740 int trailing_blank = 0;
2741
2742 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
2743 if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
2744 if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
2745
2746 /* Eat the indicator '|' or '>'. */
2747
2748 start_mark = parser->mark;
2749
2750 SKIP(parser);
2751
2752 /* Scan the additional block scalar indicators. */
2753
2754 if (!CACHE(parser, 1)) goto error;
2755
2756 /* Check for a chomping indicator. */
2757
2758 if (CHECK(parser->buffer, '+') || CHECK(parser->buffer, '-'))
2759 {
2760 /* Set the chomping method and eat the indicator. */
2761
2762 chomping = CHECK(parser->buffer, '+') ? +1 : -1;
2763
2764 SKIP(parser);
2765
2766 /* Check for an indentation indicator. */
2767
2768 if (!CACHE(parser, 1)) goto error;
2769
2770 if (IS_DIGIT(parser->buffer))
2771 {
2772 /* Check that the indentation is greater than 0. */
2773
2774 if (CHECK(parser->buffer, '0')) {
2775 yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
2776 start_mark, "found an indentation indicator equal to 0");
2777 goto error;
2778 }
2779
2780 /* Get the indentation level and eat the indicator. */
2781
2782 increment = AS_DIGIT(parser->buffer);
2783
2784 SKIP(parser);
2785 }
2786 }
2787
2788 /* Do the same as above, but in the opposite order. */
2789
2790 else if (IS_DIGIT(parser->buffer))
2791 {
2792 if (CHECK(parser->buffer, '0')) {
2793 yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
2794 start_mark, "found an indentation indicator equal to 0");
2795 goto error;
2796 }
2797
2798 increment = AS_DIGIT(parser->buffer);
2799
2800 SKIP(parser);
2801
2802 if (!CACHE(parser, 1)) goto error;
2803
2804 if (CHECK(parser->buffer, '+') || CHECK(parser->buffer, '-')) {
2805 chomping = CHECK(parser->buffer, '+') ? +1 : -1;
2806
2807 SKIP(parser);
2808 }
2809 }
2810
2811 /* Eat whitespaces and comments to the end of the line. */
2812
2813 if (!CACHE(parser, 1)) goto error;
2814
2815 while (IS_BLANK(parser->buffer)) {
2816 SKIP(parser);
2817 if (!CACHE(parser, 1)) goto error;
2818 }
2819
2820 if (CHECK(parser->buffer, '#')) {
2821 while (!IS_BREAKZ(parser->buffer)) {
2822 SKIP(parser);
2823 if (!CACHE(parser, 1)) goto error;
2824 }
2825 }
2826
2827 /* Check if we are at the end of the line. */
2828
2829 if (!IS_BREAKZ(parser->buffer)) {
2830 yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
2831 start_mark, "did not find expected comment or line break");
2832 goto error;
2833 }
2834
2835 /* Eat a line break. */
2836
2837 if (IS_BREAK(parser->buffer)) {
2838 if (!CACHE(parser, 2)) goto error;
2839 SKIP_LINE(parser);
2840 }
2841
2842 end_mark = parser->mark;
2843
2844 /* Set the indentation level if it was specified. */
2845
2846 if (increment) {
2847 indent = parser->indent >= 0 ? parser->indent+increment : increment;
2848 }
2849
2850 /* Scan the leading line breaks and determine the indentation level if needed. */
2851
2852 if (!yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks,
2853 start_mark, &end_mark)) goto error;
2854
2855 /* Scan the block scalar content. */
2856
2857 if (!CACHE(parser, 1)) goto error;
2858
2859 while ((int)parser->mark.column == indent && !IS_Z(parser->buffer))
2860 {
2861 /*
2862 * We are at the beginning of a non-empty line.
2863 */
2864
2865 /* Is it a trailing whitespace? */
2866
2867 trailing_blank = IS_BLANK(parser->buffer);
2868
2869 /* Check if we need to fold the leading line break. */
2870
2871 if (!literal && (*leading_break.start == '\n')
2872 && !leading_blank && !trailing_blank)
2873 {
2874 /* Do we need to join the lines by space? */
2875
2876 if (*trailing_breaks.start == '\0') {
2877 if (!STRING_EXTEND(parser, string)) goto error;
2878 *(string.pointer ++) = ' ';
2879 }
2880
2881 CLEAR(parser, leading_break);
2882 }
2883 else {
2884 if (!JOIN(parser, string, leading_break)) goto error;
2885 CLEAR(parser, leading_break);
2886 }
2887
2888 /* Append the remaining line breaks. */
2889
2890 if (!JOIN(parser, string, trailing_breaks)) goto error;
2891 CLEAR(parser, trailing_breaks);
2892
2893 /* Is it a leading whitespace? */
2894
2895 leading_blank = IS_BLANK(parser->buffer);
2896
2897 /* Consume the current line. */
2898
2899 while (!IS_BREAKZ(parser->buffer)) {
2900 if (!READ(parser, string)) goto error;
2901 if (!CACHE(parser, 1)) goto error;
2902 }
2903
2904 /* Consume the line break. */
2905
2906 if (!CACHE(parser, 2)) goto error;
2907
2908 if (!READ_LINE(parser, leading_break)) goto error;
2909
2910 /* Eat the following indentation spaces and line breaks. */
2911
2912 if (!yaml_parser_scan_block_scalar_breaks(parser,
2913 &indent, &trailing_breaks, start_mark, &end_mark)) goto error;
2914 }
2915
2916 /* Chomp the tail. */
2917
2918 if (chomping != -1) {
2919 if (!JOIN(parser, string, leading_break)) goto error;
2920 }
2921 if (chomping == 1) {
2922 if (!JOIN(parser, string, trailing_breaks)) goto error;
2923 }
2924
2925 /* Create a token. */
2926
2927 SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
2928 literal ? YAML_LITERAL_SCALAR_STYLE : YAML_FOLDED_SCALAR_STYLE,
2929 start_mark, end_mark);
2930
2931 STRING_DEL(parser, leading_break);
2932 STRING_DEL(parser, trailing_breaks);
2933
2934 return 1;
2935
2936 error:
2937 STRING_DEL(parser, string);
2938 STRING_DEL(parser, leading_break);
2939 STRING_DEL(parser, trailing_breaks);
2940
2941 return 0;
2942 }
2943
2944 /*
2945 * Scan indentation spaces and line breaks for a block scalar. Determine the
2946 * indentation level if needed.
2947 */
2948
2949 static int
2950 yaml_parser_scan_block_scalar_breaks(yaml_parser_t *parser,
2951 int *indent, yaml_string_t *breaks,
2952 yaml_mark_t start_mark, yaml_mark_t *end_mark)
2953 {
2954 int max_indent = 0;
2955
2956 *end_mark = parser->mark;
2957
2958 /* Eat the indentation spaces and line breaks. */
2959
2960 while (1)
2961 {
2962 /* Eat the indentation spaces. */
2963
2964 if (!CACHE(parser, 1)) return 0;
2965
2966 while ((!*indent || (int)parser->mark.column < *indent)
2967 && IS_SPACE(parser->buffer)) {
2968 SKIP(parser);
2969 if (!CACHE(parser, 1)) return 0;
2970 }
2971
2972 if ((int)parser->mark.column > max_indent)
2973 max_indent = (int)parser->mark.column;
2974
2975 /* Check for a tab character messing the indentation. */
2976
2977 if ((!*indent || (int)parser->mark.column < *indent)
2978 && IS_TAB(parser->buffer)) {
2979 return yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
2980 start_mark, "found a tab character where an indentation space is expected");
2981 }
2982
2983 /* Have we found a non-empty line? */
2984
2985 if (!IS_BREAK(parser->buffer)) break;
2986
2987 /* Consume the line break. */
2988
2989 if (!CACHE(parser, 2)) return 0;
2990 if (!READ_LINE(parser, *breaks)) return 0;
2991 *end_mark = parser->mark;
2992 }
2993
2994 /* Determine the indentation level if needed. */
2995
2996 if (!*indent) {
2997 *indent = max_indent;
2998 if (*indent < parser->indent + 1)
2999 *indent = parser->indent + 1;
3000 if (*indent < 1)
3001 *indent = 1;
3002 }
3003
3004 return 1;
3005 }
3006
3007 /*
3008 * Scan a quoted scalar.
3009 */
3010
3011 static int
3012 yaml_parser_scan_flow_scalar(yaml_parser_t *parser, yaml_token_t *token,
3013 int single)
3014 {
3015 yaml_mark_t start_mark;
3016 yaml_mark_t end_mark;
3017 yaml_string_t string = NULL_STRING;
3018 yaml_string_t leading_break = NULL_STRING;
3019 yaml_string_t trailing_breaks = NULL_STRING;
3020 yaml_string_t whitespaces = NULL_STRING;
3021 int leading_blanks;
3022
3023 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
3024 if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
3025 if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
3026 if (!STRING_INIT(parser, whitespaces, INITIAL_STRING_SIZE)) goto error;
3027
3028 /* Eat the left quote. */
3029
3030 start_mark = parser->mark;
3031
3032 SKIP(parser);
3033
3034 /* Consume the content of the quoted scalar. */
3035
3036 while (1)
3037 {
3038 /* Check that there are no document indicators at the beginning of the line. */
3039
3040 if (!CACHE(parser, 4)) goto error;
3041
3042 if (parser->mark.column == 0 &&
3043 ((CHECK_AT(parser->buffer, '-', 0) &&
3044 CHECK_AT(parser->buffer, '-', 1) &&
3045 CHECK_AT(parser->buffer, '-', 2)) ||
3046 (CHECK_AT(parser->buffer, '.', 0) &&
3047 CHECK_AT(parser->buffer, '.', 1) &&
3048 CHECK_AT(parser->buffer, '.', 2))) &&
3049 IS_BLANKZ_AT(parser->buffer, 3))
3050 {
3051 yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
3052 start_mark, "found unexpected document indicator");
3053 goto error;
3054 }
3055
3056 /* Check for EOF. */
3057
3058 if (IS_Z(parser->buffer)) {
3059 yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
3060 start_mark, "found unexpected end of stream");
3061 goto error;
3062 }
3063
3064 /* Consume non-blank characters. */
3065
3066 if (!CACHE(parser, 2)) goto error;
3067
3068 leading_blanks = 0;
3069
3070 while (!IS_BLANKZ(parser->buffer))
3071 {
3072 /* Check for an escaped single quote. */
3073
3074 if (single && CHECK_AT(parser->buffer, '\'', 0)
3075 && CHECK_AT(parser->buffer, '\'', 1))
3076 {
3077 if (!STRING_EXTEND(parser, string)) goto error;
3078 *(string.pointer++) = '\'';
3079 SKIP(parser);
3080 SKIP(parser);
3081 }
3082
3083 /* Check for the right quote. */
3084
3085 else if (CHECK(parser->buffer, single ? '\'' : '"'))
3086 {
3087 break;
3088 }
3089
3090 /* Check for an escaped line break. */
3091
3092 else if (!single && CHECK(parser->buffer, '\\')
3093 && IS_BREAK_AT(parser->buffer, 1))
3094 {
3095 if (!CACHE(parser, 3)) goto error;
3096 SKIP(parser);
3097 SKIP_LINE(parser);
3098 leading_blanks = 1;
3099 break;
3100 }
3101
3102 /* Check for an escape sequence. */
3103
3104 else if (!single && CHECK(parser->buffer, '\\'))
3105 {
3106 size_t code_length = 0;
3107
3108 if (!STRING_EXTEND(parser, string)) goto error;
3109
3110 /* Check the escape character. */
3111
3112 switch (parser->buffer.pointer[1])
3113 {
3114 case '0':
3115 *(string.pointer++) = '\0';
3116 break;
3117
3118 case 'a':
3119 *(string.pointer++) = '\x07';
3120 break;
3121
3122 case 'b':
3123 *(string.pointer++) = '\x08';
3124 break;
3125
3126 case 't':
3127 case '\t':
3128 *(string.pointer++) = '\x09';
3129 break;
3130
3131 case 'n':
3132 *(string.pointer++) = '\x0A';
3133 break;
3134
3135 case 'v':
3136 *(string.pointer++) = '\x0B';
3137 break;
3138
3139 case 'f':
3140 *(string.pointer++) = '\x0C';
3141 break;
3142
3143 case 'r':
3144 *(string.pointer++) = '\x0D';
3145 break;
3146
3147 case 'e':
3148 *(string.pointer++) = '\x1B';
3149 break;
3150
3151 case ' ':
3152 *(string.pointer++) = '\x20';
3153 break;
3154
3155 case '"':
3156 *(string.pointer++) = '"';
3157 break;
3158
3159 case '\'':
3160 *(string.pointer++) = '\'';
3161 break;
3162
3163 case '\\':
3164 *(string.pointer++) = '\\';
3165 break;
3166
3167 case 'N': /* NEL (#x85) */
3168 *(string.pointer++) = '\xC2';
3169 *(string.pointer++) = '\x85';
3170 break;
3171
3172 case '_': /* #xA0 */
3173 *(string.pointer++) = '\xC2';
3174 *(string.pointer++) = '\xA0';
3175 break;
3176
3177 case 'L': /* LS (#x2028) */
3178 *(string.pointer++) = '\xE2';
3179 *(string.pointer++) = '\x80';
3180 *(string.pointer++) = '\xA8';
3181 break;
3182
3183 case 'P': /* PS (#x2029) */
3184 *(string.pointer++) = '\xE2';
3185 *(string.pointer++) = '\x80';
3186 *(string.pointer++) = '\xA9';
3187 break;
3188
3189 case 'x':
3190 code_length = 2;
3191 break;
3192
3193 case 'u':
3194 code_length = 4;
3195 break;
3196
3197 case 'U':
3198 code_length = 8;
3199 break;
3200
3201 default:
3202 yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
3203 start_mark, "found unknown escape character");
3204 goto error;
3205 }
3206
3207 SKIP(parser);
3208 SKIP(parser);
3209
3210 /* Consume an arbitrary escape code. */
3211
3212 if (code_length)
3213 {
3214 unsigned int value = 0;
3215 size_t k;
3216
3217 /* Scan the character value. */
3218
3219 if (!CACHE(parser, code_length)) goto error;
3220
3221 for (k = 0; k < code_length; k ++) {
3222 if (!IS_HEX_AT(parser->buffer, k)) {
3223 yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
3224 start_mark, "did not find expected hexdecimal number");
3225 goto error;
3226 }
3227 value = (value << 4) + AS_HEX_AT(parser->buffer, k);
3228 }
3229
3230 /* Check the value and write the character. */
3231
3232 if ((value >= 0xD800 && value <= 0xDFFF) || value > 0x10FFFF) {
3233 yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
3234 start_mark, "found invalid Unicode character escape code");
3235 goto error;
3236 }
3237
3238 if (value <= 0x7F) {
3239 *(string.pointer++) = value;
3240 }
3241 else if (value <= 0x7FF) {
3242 *(string.pointer++) = 0xC0 + (value >> 6);
3243 *(string.pointer++) = 0x80 + (value & 0x3F);
3244 }
3245 else if (value <= 0xFFFF) {
3246 *(string.pointer++) = 0xE0 + (value >> 12);
3247 *(string.pointer++) = 0x80 + ((value >> 6) & 0x3F);
3248 *(string.pointer++) = 0x80 + (value & 0x3F);
3249 }
3250 else {
3251 *(string.pointer++) = 0xF0 + (value >> 18);
3252 *(string.pointer++) = 0x80 + ((value >> 12) & 0x3F);
3253 *(string.pointer++) = 0x80 + ((value >> 6) & 0x3F);
3254 *(string.pointer++) = 0x80 + (value & 0x3F);
3255 }
3256
3257 /* Advance the pointer. */
3258
3259 for (k = 0; k < code_length; k ++) {
3260 SKIP(parser);
3261 }
3262 }
3263 }
3264
3265 else
3266 {
3267 /* It is a non-escaped non-blank character. */
3268
3269 if (!READ(parser, string)) goto error;
3270 }
3271
3272 if (!CACHE(parser, 2)) goto error;
3273 }
3274
3275 /* Check if we are at the end of the scalar. */
3276
3277 if (CHECK(parser->buffer, single ? '\'' : '"'))
3278 break;
3279
3280 /* Consume blank characters. */
3281
3282 if (!CACHE(parser, 1)) goto error;
3283
3284 while (IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer))
3285 {
3286 if (IS_BLANK(parser->buffer))
3287 {
3288 /* Consume a space or a tab character. */
3289
3290 if (!leading_blanks) {
3291 if (!READ(parser, whitespaces)) goto error;
3292 }
3293 else {
3294 SKIP(parser);
3295 }
3296 }
3297 else
3298 {
3299 if (!CACHE(parser, 2)) goto error;
3300
3301 /* Check if it is a first line break. */
3302
3303 if (!leading_blanks)
3304 {
3305 CLEAR(parser, whitespaces);
3306 if (!READ_LINE(parser, leading_break)) goto error;
3307 leading_blanks = 1;
3308 }
3309 else
3310 {
3311 if (!READ_LINE(parser, trailing_breaks)) goto error;
3312 }
3313 }
3314 if (!CACHE(parser, 1)) goto error;
3315 }
3316
3317 /* Join the whitespaces or fold line breaks. */
3318
3319 if (leading_blanks)
3320 {
3321 /* Do we need to fold line breaks? */
3322
3323 if (leading_break.start[0] == '\n') {
3324 if (trailing_breaks.start[0] == '\0') {
3325 if (!STRING_EXTEND(parser, string)) goto error;
3326 *(string.pointer++) = ' ';
3327 }
3328 else {
3329 if (!JOIN(parser, string, trailing_breaks)) goto error;
3330 CLEAR(parser, trailing_breaks);
3331 }
3332 CLEAR(parser, leading_break);
3333 }
3334 else {
3335 if (!JOIN(parser, string, leading_break)) goto error;
3336 if (!JOIN(parser, string, trailing_breaks)) goto error;
3337 CLEAR(parser, leading_break);
3338 CLEAR(parser, trailing_breaks);
3339 }
3340 }
3341 else
3342 {
3343 if (!JOIN(parser, string, whitespaces)) goto error;
3344 CLEAR(parser, whitespaces);
3345 }
3346 }
3347
3348 /* Eat the right quote. */
3349
3350 SKIP(parser);
3351
3352 end_mark = parser->mark;
3353
3354 /* Create a token. */
3355
3356 SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
3357 single ? YAML_SINGLE_QUOTED_SCALAR_STYLE : YAML_DOUBLE_QUOTED_SCALAR_STYLE,
3358 start_mark, end_mark);
3359
3360 STRING_DEL(parser, leading_break);
3361 STRING_DEL(parser, trailing_breaks);
3362 STRING_DEL(parser, whitespaces);
3363
3364 return 1;
3365
3366 error:
3367 STRING_DEL(parser, string);
3368 STRING_DEL(parser, leading_break);
3369 STRING_DEL(parser, trailing_breaks);
3370 STRING_DEL(parser, whitespaces);
3371
3372 return 0;
3373 }
3374
3375 /*
3376 * Scan a plain scalar.
3377 */
3378
3379 static int
3380 yaml_parser_scan_plain_scalar(yaml_parser_t *parser, yaml_token_t *token)
3381 {
3382 yaml_mark_t start_mark;
3383 yaml_mark_t end_mark;
3384 yaml_string_t string = NULL_STRING;
3385 yaml_string_t leading_break = NULL_STRING;
3386 yaml_string_t trailing_breaks = NULL_STRING;
3387 yaml_string_t whitespaces = NULL_STRING;
3388 int leading_blanks = 0;
3389 int indent = parser->indent+1;
3390
3391 if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
3392 if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
3393 if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
3394 if (!STRING_INIT(parser, whitespaces, INITIAL_STRING_SIZE)) goto error;
3395
3396 start_mark = end_mark = parser->mark;
3397
3398 /* Consume the content of the plain scalar. */
3399
3400 while (1)
3401 {
3402 /* Check for a document indicator. */
3403
3404 if (!CACHE(parser, 4)) goto error;
3405
3406 if (parser->mark.column == 0 &&
3407 ((CHECK_AT(parser->buffer, '-', 0) &&
3408 CHECK_AT(parser->buffer, '-', 1) &&
3409 CHECK_AT(parser->buffer, '-', 2)) ||
3410 (CHECK_AT(parser->buffer, '.', 0) &&
3411 CHECK_AT(parser->buffer, '.', 1) &&
3412 CHECK_AT(parser->buffer, '.', 2))) &&
3413 IS_BLANKZ_AT(parser->buffer, 3)) break;
3414
3415 /* Check for a comment. */
3416
3417 if (CHECK(parser->buffer, '#'))
3418 break;
3419
3420 /* Consume non-blank characters. */
3421
3422 while (!IS_BLANKZ(parser->buffer))
3423 {
3424 /* Check for 'x:x' in the flow context. TODO: Fix the test "spec-08-13". */
3425
3426 if (parser->flow_level
3427 && CHECK(parser->buffer, ':')
3428 && !IS_BLANKZ_AT(parser->buffer, 1)) {
3429 yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
3430 start_mark, "found unexpected ':'");
3431 goto error;
3432 }
3433
3434 /* Check for indicators that may end a plain scalar. */
3435
3436 if ((CHECK(parser->buffer, ':') && IS_BLANKZ_AT(parser->buffer, 1))
3437 || (parser->flow_level &&
3438 (CHECK(parser->buffer, ',') || CHECK(parser->buffer, ':')
3439 || CHECK(parser->buffer, '?') || CHECK(parser->buffer, '[')
3440 || CHECK(parser->buffer, ']') || CHECK(parser->buffer, '{')
3441 || CHECK(parser->buffer, '}'))))
3442 break;
3443
3444 /* Check if we need to join whitespaces and breaks. */
3445
3446 if (leading_blanks || whitespaces.start != whitespaces.pointer)
3447 {
3448 if (leading_blanks)
3449 {
3450 /* Do we need to fold line breaks? */
3451
3452 if (leading_break.start[0] == '\n') {
3453 if (trailing_breaks.start[0] == '\0') {
3454 if (!STRING_EXTEND(parser, string)) goto error;
3455 *(string.pointer++) = ' ';
3456 }
3457 else {
3458 if (!JOIN(parser, string, trailing_breaks)) goto error;
3459 CLEAR(parser, trailing_breaks);
3460 }
3461 CLEAR(parser, leading_break);
3462 }
3463 else {
3464 if (!JOIN(parser, string, leading_break)) goto error;
3465 if (!JOIN(parser, string, trailing_breaks)) goto error;
3466 CLEAR(parser, leading_break);
3467 CLEAR(parser, trailing_breaks);
3468 }
3469
3470 leading_blanks = 0;
3471 }
3472 else
3473 {
3474 if (!JOIN(parser, string, whitespaces)) goto error;
3475 CLEAR(parser, whitespaces);
3476 }
3477 }
3478
3479 /* Copy the character. */
3480
3481 if (!READ(parser, string)) goto error;
3482
3483 end_mark = parser->mark;
3484
3485 if (!CACHE(parser, 2)) goto error;
3486 }
3487
3488 /* Is it the end? */
3489
3490 if (!(IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer)))
3491 break;
3492
3493 /* Consume blank characters. */
3494
3495 if (!CACHE(parser, 1)) goto error;
3496
3497 while (IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer))
3498 {
3499 if (IS_BLANK(parser->buffer))
3500 {
3501 /* Check for tab character that abuse indentation. */
3502
3503 if (leading_blanks && (int)parser->mark.column < indent
3504 && IS_TAB(parser->buffer)) {
3505 yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
3506 start_mark, "found a tab character that violates indentation");
3507 goto error;
3508 }
3509
3510 /* Consume a space or a tab character. */
3511
3512 if (!leading_blanks) {
3513 if (!READ(parser, whitespaces)) goto error;
3514 }
3515 else {
3516 SKIP(parser);
3517 }
3518 }
3519 else
3520 {
3521 if (!CACHE(parser, 2)) goto error;
3522
3523 /* Check if it is a first line break. */
3524
3525 if (!leading_blanks)
3526 {
3527 CLEAR(parser, whitespaces);
3528 if (!READ_LINE(parser, leading_break)) goto error;
3529 leading_blanks = 1;
3530 }
3531 else
3532 {
3533 if (!READ_LINE(parser, trailing_breaks)) goto error;
3534 }
3535 }
3536 if (!CACHE(parser, 1)) goto error;
3537 }
3538
3539 /* Check indentation level. */
3540
3541 if (!parser->flow_level && (int)parser->mark.column < indent)
3542 break;
3543 }
3544
3545 /* Create a token. */
3546
3547 SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
3548 YAML_PLAIN_SCALAR_STYLE, start_mark, end_mark);
3549
3550 /* Note that we change the 'simple_key_allowed' flag. */
3551
3552 if (leading_blanks) {
3553 parser->simple_key_allowed = 1;
3554 }
3555
3556 STRING_DEL(parser, leading_break);
3557 STRING_DEL(parser, trailing_breaks);
3558 STRING_DEL(parser, whitespaces);
3559
3560 return 1;
3561
3562 error:
3563 STRING_DEL(parser, string);
3564 STRING_DEL(parser, leading_break);
3565 STRING_DEL(parser, trailing_breaks);
3566 STRING_DEL(parser, whitespaces);
3567
3568 return 0;
3569 }
3570
3571