1
2#include "yaml_private.h"
3
4/*
5 * API functions.
6 */
7
8YAML_DECLARE(int)
9yaml_parser_load(yaml_parser_t *parser, yaml_document_t *document);
10
11/*
12 * Error handling.
13 */
14
15static int
16yaml_parser_set_composer_error(yaml_parser_t *parser,
17        const char *problem, yaml_mark_t problem_mark);
18
19static int
20yaml_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
29static int
30yaml_parser_register_anchor(yaml_parser_t *parser,
31        int index, yaml_char_t *anchor);
32
33/*
34 * Clean up functions.
35 */
36
37static void
38yaml_parser_delete_aliases(yaml_parser_t *parser);
39
40/*
41 * Composer functions.
42 */
43
44static int
45yaml_parser_load_document(yaml_parser_t *parser, yaml_event_t *first_event);
46
47static int
48yaml_parser_load_node(yaml_parser_t *parser, yaml_event_t *first_event);
49
50static int
51yaml_parser_load_alias(yaml_parser_t *parser, yaml_event_t *first_event);
52
53static int
54yaml_parser_load_scalar(yaml_parser_t *parser, yaml_event_t *first_event);
55
56static int
57yaml_parser_load_sequence(yaml_parser_t *parser, yaml_event_t *first_event);
58
59static int
60yaml_parser_load_mapping(yaml_parser_t *parser, yaml_event_t *first_event);
61
62/*
63 * Load the next document of the stream.
64 */
65
66YAML_DECLARE(int)
67yaml_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
105error:
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
118static int
119yaml_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
133static int
134yaml_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
151static void
152yaml_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
164static int
165yaml_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
200static int
201yaml_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
224static int
225yaml_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
259static int
260yaml_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
282static int
283yaml_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
308error:
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
319static int
320yaml_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
366error:
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
376static int
377yaml_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
427error:
428    yaml_free(tag);
429    yaml_free(first_event->data.mapping_start.anchor);
430    return 0;
431}
432
433