Ruby 2.0.0p247(2013-06-27revision41674)

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loader.c
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1
2 #include "yaml_private.h"
3
4 /*
5 * API functions.
6 */
7
8 YAML_DECLARE(int)
9 yaml_parser_load(yaml_parser_t *parser, yaml_document_t *document);
10
11 /*
12 * Error handling.
13 */
14
15 static int
16 yaml_parser_set_composer_error(yaml_parser_t *parser,
17 const char *problem, yaml_mark_t problem_mark);
18
19 static int
20 yaml_parser_set_composer_error_context(yaml_parser_t *parser,
21 const char *context, yaml_mark_t context_mark,
22 const char *problem, yaml_mark_t problem_mark);
23
24
25 /*
26 * Alias handling.
27 */
28
29 static int
30 yaml_parser_register_anchor(yaml_parser_t *parser,
31 int index, yaml_char_t *anchor);
32
33 /*
34 * Clean up functions.
35 */
36
37 static void
38 yaml_parser_delete_aliases(yaml_parser_t *parser);
39
40 /*
41 * Composer functions.
42 */
43
44 static int
45 yaml_parser_load_document(yaml_parser_t *parser, yaml_event_t *first_event);
46
47 static int
48 yaml_parser_load_node(yaml_parser_t *parser, yaml_event_t *first_event);
49
50 static int
51 yaml_parser_load_alias(yaml_parser_t *parser, yaml_event_t *first_event);
52
53 static int
54 yaml_parser_load_scalar(yaml_parser_t *parser, yaml_event_t *first_event);
55
56 static int
57 yaml_parser_load_sequence(yaml_parser_t *parser, yaml_event_t *first_event);
58
59 static int
60 yaml_parser_load_mapping(yaml_parser_t *parser, yaml_event_t *first_event);
61
62 /*
63 * Load the next document of the stream.
64 */
65
66 YAML_DECLARE(int)
67 yaml_parser_load(yaml_parser_t *parser, yaml_document_t *document)
68 {
69 yaml_event_t event;
70
71 assert(parser); /* Non-NULL parser object is expected. */
72 assert(document); /* Non-NULL document object is expected. */
73
74 memset(document, 0, sizeof(yaml_document_t));
75 if (!STACK_INIT(parser, document->nodes, INITIAL_STACK_SIZE))
76 goto error;
77
78 if (!parser->stream_start_produced) {
79 if (!yaml_parser_parse(parser, &event)) goto error;
80 assert(event.type == YAML_STREAM_START_EVENT);
81 /* STREAM-START is expected. */
82 }
83
84 if (parser->stream_end_produced) {
85 return 1;
86 }
87
88 if (!yaml_parser_parse(parser, &event)) goto error;
89 if (event.type == YAML_STREAM_END_EVENT) {
90 return 1;
91 }
92
93 if (!STACK_INIT(parser, parser->aliases, INITIAL_STACK_SIZE))
94 goto error;
95
96 parser->document = document;
97
98 if (!yaml_parser_load_document(parser, &event)) goto error;
99
100 yaml_parser_delete_aliases(parser);
101 parser->document = NULL;
102
103 return 1;
104
105 error:
106
107 yaml_parser_delete_aliases(parser);
108 yaml_document_delete(document);
109 parser->document = NULL;
110
111 return 0;
112 }
113
114 /*
115 * Set composer error.
116 */
117
118 static int
119 yaml_parser_set_composer_error(yaml_parser_t *parser,
120 const char *problem, yaml_mark_t problem_mark)
121 {
122 parser->error = YAML_COMPOSER_ERROR;
123 parser->problem = problem;
124 parser->problem_mark = problem_mark;
125
126 return 0;
127 }
128
129 /*
130 * Set composer error with context.
131 */
132
133 static int
134 yaml_parser_set_composer_error_context(yaml_parser_t *parser,
135 const char *context, yaml_mark_t context_mark,
136 const char *problem, yaml_mark_t problem_mark)
137 {
138 parser->error = YAML_COMPOSER_ERROR;
139 parser->context = context;
140 parser->context_mark = context_mark;
141 parser->problem = problem;
142 parser->problem_mark = problem_mark;
143
144 return 0;
145 }
146
147 /*
148 * Delete the stack of aliases.
149 */
150
151 static void
152 yaml_parser_delete_aliases(yaml_parser_t *parser)
153 {
154 while (!STACK_EMPTY(parser, parser->aliases)) {
155 yaml_free(POP(parser, parser->aliases).anchor);
156 }
157 STACK_DEL(parser, parser->aliases);
158 }
159
160 /*
161 * Compose a document object.
162 */
163
164 static int
165 yaml_parser_load_document(yaml_parser_t *parser, yaml_event_t *first_event)
166 {
167 yaml_event_t event;
168
169 assert(first_event->type == YAML_DOCUMENT_START_EVENT);
170 /* DOCUMENT-START is expected. */
171
172 parser->document->version_directive
173 = first_event->data.document_start.version_directive;
174 parser->document->tag_directives.start
175 = first_event->data.document_start.tag_directives.start;
176 parser->document->tag_directives.end
177 = first_event->data.document_start.tag_directives.end;
178 parser->document->start_implicit
179 = first_event->data.document_start.implicit;
180 parser->document->start_mark = first_event->start_mark;
181
182 if (!yaml_parser_parse(parser, &event)) return 0;
183
184 if (!yaml_parser_load_node(parser, &event)) return 0;
185
186 if (!yaml_parser_parse(parser, &event)) return 0;
187 assert(event.type == YAML_DOCUMENT_END_EVENT);
188 /* DOCUMENT-END is expected. */
189
190 parser->document->end_implicit = event.data.document_end.implicit;
191 parser->document->end_mark = event.end_mark;
192
193 return 1;
194 }
195
196 /*
197 * Compose a node.
198 */
199
200 static int
201 yaml_parser_load_node(yaml_parser_t *parser, yaml_event_t *first_event)
202 {
203 switch (first_event->type) {
204 case YAML_ALIAS_EVENT:
205 return yaml_parser_load_alias(parser, first_event);
206 case YAML_SCALAR_EVENT:
207 return yaml_parser_load_scalar(parser, first_event);
208 case YAML_SEQUENCE_START_EVENT:
209 return yaml_parser_load_sequence(parser, first_event);
210 case YAML_MAPPING_START_EVENT:
211 return yaml_parser_load_mapping(parser, first_event);
212 default:
213 assert(0); /* Could not happen. */
214 return 0;
215 }
216
217 return 0;
218 }
219
220 /*
221 * Add an anchor.
222 */
223
224 static int
225 yaml_parser_register_anchor(yaml_parser_t *parser,
226 int index, yaml_char_t *anchor)
227 {
228 yaml_alias_data_t data;
229 yaml_alias_data_t *alias_data;
230
231 if (!anchor) return 1;
232
233 data.anchor = anchor;
234 data.index = index;
235 data.mark = parser->document->nodes.start[index-1].start_mark;
236
237 for (alias_data = parser->aliases.start;
238 alias_data != parser->aliases.top; alias_data ++) {
239 if (strcmp((char *)alias_data->anchor, (char *)anchor) == 0) {
240 yaml_free(anchor);
241 return yaml_parser_set_composer_error_context(parser,
242 "found duplicate anchor; first occurence",
243 alias_data->mark, "second occurence", data.mark);
244 }
245 }
246
247 if (!PUSH(parser, parser->aliases, data)) {
248 yaml_free(anchor);
249 return 0;
250 }
251
252 return 1;
253 }
254
255 /*
256 * Compose a node corresponding to an alias.
257 */
258
259 static int
260 yaml_parser_load_alias(yaml_parser_t *parser, yaml_event_t *first_event)
261 {
262 yaml_char_t *anchor = first_event->data.alias.anchor;
263 yaml_alias_data_t *alias_data;
264
265 for (alias_data = parser->aliases.start;
266 alias_data != parser->aliases.top; alias_data ++) {
267 if (strcmp((char *)alias_data->anchor, (char *)anchor) == 0) {
268 yaml_free(anchor);
269 return alias_data->index;
270 }
271 }
272
273 yaml_free(anchor);
274 return yaml_parser_set_composer_error(parser, "found undefined alias",
275 first_event->start_mark);
276 }
277
278 /*
279 * Compose a scalar node.
280 */
281
282 static int
283 yaml_parser_load_scalar(yaml_parser_t *parser, yaml_event_t *first_event)
284 {
285 yaml_node_t node;
286 int index;
287 yaml_char_t *tag = first_event->data.scalar.tag;
288
289 if (!tag || strcmp((char *)tag, "!") == 0) {
290 yaml_free(tag);
291 tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_SCALAR_TAG);
292 if (!tag) goto error;
293 }
294
295 SCALAR_NODE_INIT(node, tag, first_event->data.scalar.value,
296 first_event->data.scalar.length, first_event->data.scalar.style,
297 first_event->start_mark, first_event->end_mark);
298
299 if (!PUSH(parser, parser->document->nodes, node)) goto error;
300
301 index = parser->document->nodes.top - parser->document->nodes.start;
302
303 if (!yaml_parser_register_anchor(parser, index,
304 first_event->data.scalar.anchor)) return 0;
305
306 return index;
307
308 error:
309 yaml_free(tag);
310 yaml_free(first_event->data.scalar.anchor);
311 yaml_free(first_event->data.scalar.value);
312 return 0;
313 }
314
315 /*
316 * Compose a sequence node.
317 */
318
319 static int
320 yaml_parser_load_sequence(yaml_parser_t *parser, yaml_event_t *first_event)
321 {
322 yaml_event_t event;
323 yaml_node_t node;
324 struct {
325 yaml_node_item_t *start;
326 yaml_node_item_t *end;
327 yaml_node_item_t *top;
328 } items = { NULL, NULL, NULL };
329 int index, item_index;
330 yaml_char_t *tag = first_event->data.sequence_start.tag;
331
332 if (!tag || strcmp((char *)tag, "!") == 0) {
333 yaml_free(tag);
334 tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG);
335 if (!tag) goto error;
336 }
337
338 if (!STACK_INIT(parser, items, INITIAL_STACK_SIZE)) goto error;
339
340 SEQUENCE_NODE_INIT(node, tag, items.start, items.end,
341 first_event->data.sequence_start.style,
342 first_event->start_mark, first_event->end_mark);
343
344 if (!PUSH(parser, parser->document->nodes, node)) goto error;
345
346 index = parser->document->nodes.top - parser->document->nodes.start;
347
348 if (!yaml_parser_register_anchor(parser, index,
349 first_event->data.sequence_start.anchor)) return 0;
350
351 if (!yaml_parser_parse(parser, &event)) return 0;
352
353 while (event.type != YAML_SEQUENCE_END_EVENT) {
354 item_index = yaml_parser_load_node(parser, &event);
355 if (!item_index) return 0;
356 if (!PUSH(parser,
357 parser->document->nodes.start[index-1].data.sequence.items,
358 item_index)) return 0;
359 if (!yaml_parser_parse(parser, &event)) return 0;
360 }
361
362 parser->document->nodes.start[index-1].end_mark = event.end_mark;
363
364 return index;
365
366 error:
367 yaml_free(tag);
368 yaml_free(first_event->data.sequence_start.anchor);
369 return 0;
370 }
371
372 /*
373 * Compose a mapping node.
374 */
375
376 static int
377 yaml_parser_load_mapping(yaml_parser_t *parser, yaml_event_t *first_event)
378 {
379 yaml_event_t event;
380 yaml_node_t node;
381 struct {
382 yaml_node_pair_t *start;
383 yaml_node_pair_t *end;
384 yaml_node_pair_t *top;
385 } pairs = { NULL, NULL, NULL };
386 int index;
387 yaml_node_pair_t pair;
388 yaml_char_t *tag = first_event->data.mapping_start.tag;
389
390 if (!tag || strcmp((char *)tag, "!") == 0) {
391 yaml_free(tag);
392 tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_MAPPING_TAG);
393 if (!tag) goto error;
394 }
395
396 if (!STACK_INIT(parser, pairs, INITIAL_STACK_SIZE)) goto error;
397
398 MAPPING_NODE_INIT(node, tag, pairs.start, pairs.end,
399 first_event->data.mapping_start.style,
400 first_event->start_mark, first_event->end_mark);
401
402 if (!PUSH(parser, parser->document->nodes, node)) goto error;
403
404 index = parser->document->nodes.top - parser->document->nodes.start;
405
406 if (!yaml_parser_register_anchor(parser, index,
407 first_event->data.mapping_start.anchor)) return 0;
408
409 if (!yaml_parser_parse(parser, &event)) return 0;
410
411 while (event.type != YAML_MAPPING_END_EVENT) {
412 pair.key = yaml_parser_load_node(parser, &event);
413 if (!pair.key) return 0;
414 if (!yaml_parser_parse(parser, &event)) return 0;
415 pair.value = yaml_parser_load_node(parser, &event);
416 if (!pair.value) return 0;
417 if (!PUSH(parser,
418 parser->document->nodes.start[index-1].data.mapping.pairs,
419 pair)) return 0;
420 if (!yaml_parser_parse(parser, &event)) return 0;
421 }
422
423 parser->document->nodes.start[index-1].end_mark = event.end_mark;
424
425 return index;
426
427 error:
428 yaml_free(tag);
429 yaml_free(first_event->data.mapping_start.anchor);
430 return 0;
431 }
432
433