diff options
Diffstat (limited to 'loader.c')
| -rw-r--r-- | loader.c | 444 |
1 files changed, 444 insertions, 0 deletions
diff --git a/loader.c b/loader.c new file mode 100644 index 0000000..db8501a --- /dev/null +++ b/loader.c @@ -0,0 +1,444 @@ + +#include "yaml_private.h" + +/* + * API functions. + */ + +YAML_DECLARE(int) +yaml_parser_load(yaml_parser_t *parser, yaml_document_t *document); + +/* + * Error handling. + */ + +static int +yaml_parser_set_composer_error(yaml_parser_t *parser, + const char *problem, yaml_mark_t problem_mark); + +static int +yaml_parser_set_composer_error_context(yaml_parser_t *parser, + const char *context, yaml_mark_t context_mark, + const char *problem, yaml_mark_t problem_mark); + + +/* + * Alias handling. + */ + +static int +yaml_parser_register_anchor(yaml_parser_t *parser, + int index, yaml_char_t *anchor); + +/* + * Clean up functions. + */ + +static void +yaml_parser_delete_aliases(yaml_parser_t *parser); + +/* + * Composer functions. + */ + +static int +yaml_parser_load_document(yaml_parser_t *parser, yaml_event_t *first_event); + +static int +yaml_parser_load_node(yaml_parser_t *parser, yaml_event_t *first_event); + +static int +yaml_parser_load_alias(yaml_parser_t *parser, yaml_event_t *first_event); + +static int +yaml_parser_load_scalar(yaml_parser_t *parser, yaml_event_t *first_event); + +static int +yaml_parser_load_sequence(yaml_parser_t *parser, yaml_event_t *first_event); + +static int +yaml_parser_load_mapping(yaml_parser_t *parser, yaml_event_t *first_event); + +/* + * Load the next document of the stream. + */ + +YAML_DECLARE(int) +yaml_parser_load(yaml_parser_t *parser, yaml_document_t *document) +{ + yaml_event_t event; + + assert(parser); /* Non-NULL parser object is expected. */ + assert(document); /* Non-NULL document object is expected. */ + + memset(document, 0, sizeof(yaml_document_t)); + if (!STACK_INIT(parser, document->nodes, yaml_node_t*)) + goto error; + + if (!parser->stream_start_produced) { + if (!yaml_parser_parse(parser, &event)) goto error; + assert(event.type == YAML_STREAM_START_EVENT); + /* STREAM-START is expected. */ + } + + if (parser->stream_end_produced) { + return 1; + } + + if (!yaml_parser_parse(parser, &event)) goto error; + if (event.type == YAML_STREAM_END_EVENT) { + return 1; + } + + if (!STACK_INIT(parser, parser->aliases, yaml_alias_data_t*)) + goto error; + + parser->document = document; + + if (!yaml_parser_load_document(parser, &event)) goto error; + + yaml_parser_delete_aliases(parser); + parser->document = NULL; + + return 1; + +error: + + yaml_parser_delete_aliases(parser); + yaml_document_delete(document); + parser->document = NULL; + + return 0; +} + +/* + * Set composer error. + */ + +static int +yaml_parser_set_composer_error(yaml_parser_t *parser, + const char *problem, yaml_mark_t problem_mark) +{ + parser->error = YAML_COMPOSER_ERROR; + parser->problem = problem; + parser->problem_mark = problem_mark; + + return 0; +} + +/* + * Set composer error with context. + */ + +static int +yaml_parser_set_composer_error_context(yaml_parser_t *parser, + const char *context, yaml_mark_t context_mark, + const char *problem, yaml_mark_t problem_mark) +{ + parser->error = YAML_COMPOSER_ERROR; + parser->context = context; + parser->context_mark = context_mark; + parser->problem = problem; + parser->problem_mark = problem_mark; + + return 0; +} + +/* + * Delete the stack of aliases. + */ + +static void +yaml_parser_delete_aliases(yaml_parser_t *parser) +{ + while (!STACK_EMPTY(parser, parser->aliases)) { + yaml_free(POP(parser, parser->aliases).anchor); + } + STACK_DEL(parser, parser->aliases); +} + +/* + * Compose a document object. + */ + +static int +yaml_parser_load_document(yaml_parser_t *parser, yaml_event_t *first_event) +{ + yaml_event_t event; + + assert(first_event->type == YAML_DOCUMENT_START_EVENT); + /* DOCUMENT-START is expected. */ + + parser->document->version_directive + = first_event->data.document_start.version_directive; + parser->document->tag_directives.start + = first_event->data.document_start.tag_directives.start; + parser->document->tag_directives.end + = first_event->data.document_start.tag_directives.end; + parser->document->start_implicit + = first_event->data.document_start.implicit; + parser->document->start_mark = first_event->start_mark; + + if (!yaml_parser_parse(parser, &event)) return 0; + + if (!yaml_parser_load_node(parser, &event)) return 0; + + if (!yaml_parser_parse(parser, &event)) return 0; + assert(event.type == YAML_DOCUMENT_END_EVENT); + /* DOCUMENT-END is expected. */ + + parser->document->end_implicit = event.data.document_end.implicit; + parser->document->end_mark = event.end_mark; + + return 1; +} + +/* + * Compose a node. + */ + +static int +yaml_parser_load_node(yaml_parser_t *parser, yaml_event_t *first_event) +{ + switch (first_event->type) { + case YAML_ALIAS_EVENT: + return yaml_parser_load_alias(parser, first_event); + case YAML_SCALAR_EVENT: + return yaml_parser_load_scalar(parser, first_event); + case YAML_SEQUENCE_START_EVENT: + return yaml_parser_load_sequence(parser, first_event); + case YAML_MAPPING_START_EVENT: + return yaml_parser_load_mapping(parser, first_event); + default: + assert(0); /* Could not happen. */ + return 0; + } + + return 0; +} + +/* + * Add an anchor. + */ + +static int +yaml_parser_register_anchor(yaml_parser_t *parser, + int index, yaml_char_t *anchor) +{ + yaml_alias_data_t data; + yaml_alias_data_t *alias_data; + + if (!anchor) return 1; + + data.anchor = anchor; + data.index = index; + data.mark = parser->document->nodes.start[index-1].start_mark; + + for (alias_data = parser->aliases.start; + alias_data != parser->aliases.top; alias_data ++) { + if (strcmp((char *)alias_data->anchor, (char *)anchor) == 0) { + yaml_free(anchor); + return yaml_parser_set_composer_error_context(parser, + "found duplicate anchor; first occurrence", + alias_data->mark, "second occurrence", data.mark); + } + } + + if (!PUSH(parser, parser->aliases, data)) { + yaml_free(anchor); + return 0; + } + + return 1; +} + +/* + * Compose a node corresponding to an alias. + */ + +static int +yaml_parser_load_alias(yaml_parser_t *parser, yaml_event_t *first_event) +{ + yaml_char_t *anchor = first_event->data.alias.anchor; + yaml_alias_data_t *alias_data; + + for (alias_data = parser->aliases.start; + alias_data != parser->aliases.top; alias_data ++) { + if (strcmp((char *)alias_data->anchor, (char *)anchor) == 0) { + yaml_free(anchor); + return alias_data->index; + } + } + + yaml_free(anchor); + return yaml_parser_set_composer_error(parser, "found undefined alias", + first_event->start_mark); +} + +/* + * Compose a scalar node. + */ + +static int +yaml_parser_load_scalar(yaml_parser_t *parser, yaml_event_t *first_event) +{ + yaml_node_t node; + int index; + yaml_char_t *tag = first_event->data.scalar.tag; + + if (!STACK_LIMIT(parser, parser->document->nodes, INT_MAX-1)) goto error; + + if (!tag || strcmp((char *)tag, "!") == 0) { + yaml_free(tag); + tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_SCALAR_TAG); + if (!tag) goto error; + } + + SCALAR_NODE_INIT(node, tag, first_event->data.scalar.value, + first_event->data.scalar.length, first_event->data.scalar.style, + first_event->start_mark, first_event->end_mark); + + if (!PUSH(parser, parser->document->nodes, node)) goto error; + + index = parser->document->nodes.top - parser->document->nodes.start; + + if (!yaml_parser_register_anchor(parser, index, + first_event->data.scalar.anchor)) return 0; + + return index; + +error: + yaml_free(tag); + yaml_free(first_event->data.scalar.anchor); + yaml_free(first_event->data.scalar.value); + return 0; +} + +/* + * Compose a sequence node. + */ + +static int +yaml_parser_load_sequence(yaml_parser_t *parser, yaml_event_t *first_event) +{ + yaml_event_t event; + yaml_node_t node; + struct { + yaml_node_item_t *start; + yaml_node_item_t *end; + yaml_node_item_t *top; + } items = { NULL, NULL, NULL }; + int index, item_index; + yaml_char_t *tag = first_event->data.sequence_start.tag; + + if (!STACK_LIMIT(parser, parser->document->nodes, INT_MAX-1)) goto error; + + if (!tag || strcmp((char *)tag, "!") == 0) { + yaml_free(tag); + tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_SEQUENCE_TAG); + if (!tag) goto error; + } + + if (!STACK_INIT(parser, items, yaml_node_item_t*)) goto error; + + SEQUENCE_NODE_INIT(node, tag, items.start, items.end, + first_event->data.sequence_start.style, + first_event->start_mark, first_event->end_mark); + + if (!PUSH(parser, parser->document->nodes, node)) goto error; + + index = parser->document->nodes.top - parser->document->nodes.start; + + if (!yaml_parser_register_anchor(parser, index, + first_event->data.sequence_start.anchor)) return 0; + + if (!yaml_parser_parse(parser, &event)) return 0; + + while (event.type != YAML_SEQUENCE_END_EVENT) { + if (!STACK_LIMIT(parser, + parser->document->nodes.start[index-1].data.sequence.items, + INT_MAX-1)) return 0; + item_index = yaml_parser_load_node(parser, &event); + if (!item_index) return 0; + if (!PUSH(parser, + parser->document->nodes.start[index-1].data.sequence.items, + item_index)) return 0; + if (!yaml_parser_parse(parser, &event)) return 0; + } + + parser->document->nodes.start[index-1].end_mark = event.end_mark; + + return index; + +error: + yaml_free(tag); + yaml_free(first_event->data.sequence_start.anchor); + return 0; +} + +/* + * Compose a mapping node. + */ + +static int +yaml_parser_load_mapping(yaml_parser_t *parser, yaml_event_t *first_event) +{ + yaml_event_t event; + yaml_node_t node; + struct { + yaml_node_pair_t *start; + yaml_node_pair_t *end; + yaml_node_pair_t *top; + } pairs = { NULL, NULL, NULL }; + int index; + yaml_node_pair_t pair; + yaml_char_t *tag = first_event->data.mapping_start.tag; + + if (!STACK_LIMIT(parser, parser->document->nodes, INT_MAX-1)) goto error; + + if (!tag || strcmp((char *)tag, "!") == 0) { + yaml_free(tag); + tag = yaml_strdup((yaml_char_t *)YAML_DEFAULT_MAPPING_TAG); + if (!tag) goto error; + } + + if (!STACK_INIT(parser, pairs, yaml_node_pair_t*)) goto error; + + MAPPING_NODE_INIT(node, tag, pairs.start, pairs.end, + first_event->data.mapping_start.style, + first_event->start_mark, first_event->end_mark); + + if (!PUSH(parser, parser->document->nodes, node)) goto error; + + index = parser->document->nodes.top - parser->document->nodes.start; + + if (!yaml_parser_register_anchor(parser, index, + first_event->data.mapping_start.anchor)) return 0; + + if (!yaml_parser_parse(parser, &event)) return 0; + + while (event.type != YAML_MAPPING_END_EVENT) { + if (!STACK_LIMIT(parser, + parser->document->nodes.start[index-1].data.mapping.pairs, + INT_MAX-1)) return 0; + pair.key = yaml_parser_load_node(parser, &event); + if (!pair.key) return 0; + if (!yaml_parser_parse(parser, &event)) return 0; + pair.value = yaml_parser_load_node(parser, &event); + if (!pair.value) return 0; + if (!PUSH(parser, + parser->document->nodes.start[index-1].data.mapping.pairs, + pair)) return 0; + if (!yaml_parser_parse(parser, &event)) return 0; + } + + parser->document->nodes.start[index-1].end_mark = event.end_mark; + + return index; + +error: + yaml_free(tag); + yaml_free(first_event->data.mapping_start.anchor); + return 0; +} + |