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ruby--ruby/ext/psych/yaml/scanner.c
hsbt e221c6cefc * ext/psych/lib/psych.rb: Merge psych-2.0.5. bump version to 
libyaml-0.1.6 for CVE-2014-2525.
* ext/psych/yaml/config.h: ditto.
* ext/psych/yaml/scanner.c: ditto.
* ext/psych/yaml/yaml_private.h: ditto.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45453 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
2014-03-28 00:19:15 +00:00

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/*
* Introduction
* ************
*
* The following notes assume that you are familiar with the YAML specification
* (http://yaml.org/spec/cvs/current.html). We mostly follow it, although in
* some cases we are less restrictive that it requires.
*
* The process of transforming a YAML stream into a sequence of events is
* divided on two steps: Scanning and Parsing.
*
* The Scanner transforms the input stream into a sequence of tokens, while the
* parser transform the sequence of tokens produced by the Scanner into a
* sequence of parsing events.
*
* The Scanner is rather clever and complicated. The Parser, on the contrary,
* is a straightforward implementation of a recursive-descendant parser (or,
* LL(1) parser, as it is usually called).
*
* Actually there are two issues of Scanning that might be called "clever", the
* rest is quite straightforward. The issues are "block collection start" and
* "simple keys". Both issues are explained below in details.
*
* Here the Scanning step is explained and implemented. We start with the list
* of all the tokens produced by the Scanner together with short descriptions.
*
* Now, tokens:
*
* STREAM-START(encoding) # The stream start.
* STREAM-END # The stream end.
* VERSION-DIRECTIVE(major,minor) # The '%YAML' directive.
* TAG-DIRECTIVE(handle,prefix) # The '%TAG' directive.
* DOCUMENT-START # '---'
* DOCUMENT-END # '...'
* BLOCK-SEQUENCE-START # Indentation increase denoting a block
* BLOCK-MAPPING-START # sequence or a block mapping.
* BLOCK-END # Indentation decrease.
* FLOW-SEQUENCE-START # '['
* FLOW-SEQUENCE-END # ']'
* BLOCK-SEQUENCE-START # '{'
* BLOCK-SEQUENCE-END # '}'
* BLOCK-ENTRY # '-'
* FLOW-ENTRY # ','
* KEY # '?' or nothing (simple keys).
* VALUE # ':'
* ALIAS(anchor) # '*anchor'
* ANCHOR(anchor) # '&anchor'
* TAG(handle,suffix) # '!handle!suffix'
* SCALAR(value,style) # A scalar.
*
* The following two tokens are "virtual" tokens denoting the beginning and the
* end of the stream:
*
* STREAM-START(encoding)
* STREAM-END
*
* We pass the information about the input stream encoding with the
* STREAM-START token.
*
* The next two tokens are responsible for tags:
*
* VERSION-DIRECTIVE(major,minor)
* TAG-DIRECTIVE(handle,prefix)
*
* Example:
*
* %YAML 1.1
* %TAG ! !foo
* %TAG !yaml! tag:yaml.org,2002:
* ---
*
* The corresponding sequence of tokens:
*
* STREAM-START(utf-8)
* VERSION-DIRECTIVE(1,1)
* TAG-DIRECTIVE("!","!foo")
* TAG-DIRECTIVE("!yaml","tag:yaml.org,2002:")
* DOCUMENT-START
* STREAM-END
*
* Note that the VERSION-DIRECTIVE and TAG-DIRECTIVE tokens occupy a whole
* line.
*
* The document start and end indicators are represented by:
*
* DOCUMENT-START
* DOCUMENT-END
*
* Note that if a YAML stream contains an implicit document (without '---'
* and '...' indicators), no DOCUMENT-START and DOCUMENT-END tokens will be
* produced.
*
* In the following examples, we present whole documents together with the
* produced tokens.
*
* 1. An implicit document:
*
* 'a scalar'
*
* Tokens:
*
* STREAM-START(utf-8)
* SCALAR("a scalar",single-quoted)
* STREAM-END
*
* 2. An explicit document:
*
* ---
* 'a scalar'
* ...
*
* Tokens:
*
* STREAM-START(utf-8)
* DOCUMENT-START
* SCALAR("a scalar",single-quoted)
* DOCUMENT-END
* STREAM-END
*
* 3. Several documents in a stream:
*
* 'a scalar'
* ---
* 'another scalar'
* ---
* 'yet another scalar'
*
* Tokens:
*
* STREAM-START(utf-8)
* SCALAR("a scalar",single-quoted)
* DOCUMENT-START
* SCALAR("another scalar",single-quoted)
* DOCUMENT-START
* SCALAR("yet another scalar",single-quoted)
* STREAM-END
*
* We have already introduced the SCALAR token above. The following tokens are
* used to describe aliases, anchors, tag, and scalars:
*
* ALIAS(anchor)
* ANCHOR(anchor)
* TAG(handle,suffix)
* SCALAR(value,style)
*
* The following series of examples illustrate the usage of these tokens:
*
* 1. A recursive sequence:
*
* &A [ *A ]
*
* Tokens:
*
* STREAM-START(utf-8)
* ANCHOR("A")
* FLOW-SEQUENCE-START
* ALIAS("A")
* FLOW-SEQUENCE-END
* STREAM-END
*
* 2. A tagged scalar:
*
* !!float "3.14" # A good approximation.
*
* Tokens:
*
* STREAM-START(utf-8)
* TAG("!!","float")
* SCALAR("3.14",double-quoted)
* STREAM-END
*
* 3. Various scalar styles:
*
* --- # Implicit empty plain scalars do not produce tokens.
* --- a plain scalar
* --- 'a single-quoted scalar'
* --- "a double-quoted scalar"
* --- |-
* a literal scalar
* --- >-
* a folded
* scalar
*
* Tokens:
*
* STREAM-START(utf-8)
* DOCUMENT-START
* DOCUMENT-START
* SCALAR("a plain scalar",plain)
* DOCUMENT-START
* SCALAR("a single-quoted scalar",single-quoted)
* DOCUMENT-START
* SCALAR("a double-quoted scalar",double-quoted)
* DOCUMENT-START
* SCALAR("a literal scalar",literal)
* DOCUMENT-START
* SCALAR("a folded scalar",folded)
* STREAM-END
*
* Now it's time to review collection-related tokens. We will start with
* flow collections:
*
* FLOW-SEQUENCE-START
* FLOW-SEQUENCE-END
* FLOW-MAPPING-START
* FLOW-MAPPING-END
* FLOW-ENTRY
* KEY
* VALUE
*
* The tokens FLOW-SEQUENCE-START, FLOW-SEQUENCE-END, FLOW-MAPPING-START, and
* FLOW-MAPPING-END represent the indicators '[', ']', '{', and '}'
* correspondingly. FLOW-ENTRY represent the ',' indicator. Finally the
* indicators '?' and ':', which are used for denoting mapping keys and values,
* are represented by the KEY and VALUE tokens.
*
* The following examples show flow collections:
*
* 1. A flow sequence:
*
* [item 1, item 2, item 3]
*
* Tokens:
*
* STREAM-START(utf-8)
* FLOW-SEQUENCE-START
* SCALAR("item 1",plain)
* FLOW-ENTRY
* SCALAR("item 2",plain)
* FLOW-ENTRY
* SCALAR("item 3",plain)
* FLOW-SEQUENCE-END
* STREAM-END
*
* 2. A flow mapping:
*
* {
* a simple key: a value, # Note that the KEY token is produced.
* ? a complex key: another value,
* }
*
* Tokens:
*
* STREAM-START(utf-8)
* FLOW-MAPPING-START
* KEY
* SCALAR("a simple key",plain)
* VALUE
* SCALAR("a value",plain)
* FLOW-ENTRY
* KEY
* SCALAR("a complex key",plain)
* VALUE
* SCALAR("another value",plain)
* FLOW-ENTRY
* FLOW-MAPPING-END
* STREAM-END
*
* A simple key is a key which is not denoted by the '?' indicator. Note that
* the Scanner still produce the KEY token whenever it encounters a simple key.
*
* For scanning block collections, the following tokens are used (note that we
* repeat KEY and VALUE here):
*
* BLOCK-SEQUENCE-START
* BLOCK-MAPPING-START
* BLOCK-END
* BLOCK-ENTRY
* KEY
* VALUE
*
* The tokens BLOCK-SEQUENCE-START and BLOCK-MAPPING-START denote indentation
* increase that precedes a block collection (cf. the INDENT token in Python).
* The token BLOCK-END denote indentation decrease that ends a block collection
* (cf. the DEDENT token in Python). However YAML has some syntax pecularities
* that makes detections of these tokens more complex.
*
* The tokens BLOCK-ENTRY, KEY, and VALUE are used to represent the indicators
* '-', '?', and ':' correspondingly.
*
* The following examples show how the tokens BLOCK-SEQUENCE-START,
* BLOCK-MAPPING-START, and BLOCK-END are emitted by the Scanner:
*
* 1. Block sequences:
*
* - item 1
* - item 2
* -
* - item 3.1
* - item 3.2
* -
* key 1: value 1
* key 2: value 2
*
* Tokens:
*
* STREAM-START(utf-8)
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* SCALAR("item 1",plain)
* BLOCK-ENTRY
* SCALAR("item 2",plain)
* BLOCK-ENTRY
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* SCALAR("item 3.1",plain)
* BLOCK-ENTRY
* SCALAR("item 3.2",plain)
* BLOCK-END
* BLOCK-ENTRY
* BLOCK-MAPPING-START
* KEY
* SCALAR("key 1",plain)
* VALUE
* SCALAR("value 1",plain)
* KEY
* SCALAR("key 2",plain)
* VALUE
* SCALAR("value 2",plain)
* BLOCK-END
* BLOCK-END
* STREAM-END
*
* 2. Block mappings:
*
* a simple key: a value # The KEY token is produced here.
* ? a complex key
* : another value
* a mapping:
* key 1: value 1
* key 2: value 2
* a sequence:
* - item 1
* - item 2
*
* Tokens:
*
* STREAM-START(utf-8)
* BLOCK-MAPPING-START
* KEY
* SCALAR("a simple key",plain)
* VALUE
* SCALAR("a value",plain)
* KEY
* SCALAR("a complex key",plain)
* VALUE
* SCALAR("another value",plain)
* KEY
* SCALAR("a mapping",plain)
* BLOCK-MAPPING-START
* KEY
* SCALAR("key 1",plain)
* VALUE
* SCALAR("value 1",plain)
* KEY
* SCALAR("key 2",plain)
* VALUE
* SCALAR("value 2",plain)
* BLOCK-END
* KEY
* SCALAR("a sequence",plain)
* VALUE
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* SCALAR("item 1",plain)
* BLOCK-ENTRY
* SCALAR("item 2",plain)
* BLOCK-END
* BLOCK-END
* STREAM-END
*
* YAML does not always require to start a new block collection from a new
* line. If the current line contains only '-', '?', and ':' indicators, a new
* block collection may start at the current line. The following examples
* illustrate this case:
*
* 1. Collections in a sequence:
*
* - - item 1
* - item 2
* - key 1: value 1
* key 2: value 2
* - ? complex key
* : complex value
*
* Tokens:
*
* STREAM-START(utf-8)
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* SCALAR("item 1",plain)
* BLOCK-ENTRY
* SCALAR("item 2",plain)
* BLOCK-END
* BLOCK-ENTRY
* BLOCK-MAPPING-START
* KEY
* SCALAR("key 1",plain)
* VALUE
* SCALAR("value 1",plain)
* KEY
* SCALAR("key 2",plain)
* VALUE
* SCALAR("value 2",plain)
* BLOCK-END
* BLOCK-ENTRY
* BLOCK-MAPPING-START
* KEY
* SCALAR("complex key")
* VALUE
* SCALAR("complex value")
* BLOCK-END
* BLOCK-END
* STREAM-END
*
* 2. Collections in a mapping:
*
* ? a sequence
* : - item 1
* - item 2
* ? a mapping
* : key 1: value 1
* key 2: value 2
*
* Tokens:
*
* STREAM-START(utf-8)
* BLOCK-MAPPING-START
* KEY
* SCALAR("a sequence",plain)
* VALUE
* BLOCK-SEQUENCE-START
* BLOCK-ENTRY
* SCALAR("item 1",plain)
* BLOCK-ENTRY
* SCALAR("item 2",plain)
* BLOCK-END
* KEY
* SCALAR("a mapping",plain)
* VALUE
* BLOCK-MAPPING-START
* KEY
* SCALAR("key 1",plain)
* VALUE
* SCALAR("value 1",plain)
* KEY
* SCALAR("key 2",plain)
* VALUE
* SCALAR("value 2",plain)
* BLOCK-END
* BLOCK-END
* STREAM-END
*
* YAML also permits non-indented sequences if they are included into a block
* mapping. In this case, the token BLOCK-SEQUENCE-START is not produced:
*
* key:
* - item 1 # BLOCK-SEQUENCE-START is NOT produced here.
* - item 2
*
* Tokens:
*
* STREAM-START(utf-8)
* BLOCK-MAPPING-START
* KEY
* SCALAR("key",plain)
* VALUE
* BLOCK-ENTRY
* SCALAR("item 1",plain)
* BLOCK-ENTRY
* SCALAR("item 2",plain)
* BLOCK-END
*/
#include "yaml_private.h"
/*
* Ensure that the buffer contains the required number of characters.
* Return 1 on success, 0 on failure (reader error or memory error).
*/
#define CACHE(parser,length) \
(parser->unread >= (length) \
? 1 \
: yaml_parser_update_buffer(parser, (length)))
/*
* Advance the buffer pointer.
*/
#define SKIP(parser) \
(parser->mark.index ++, \
parser->mark.column ++, \
parser->unread --, \
parser->buffer.pointer += WIDTH(parser->buffer))
#define SKIP_LINE(parser) \
(IS_CRLF(parser->buffer) ? \
(parser->mark.index += 2, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread -= 2, \
parser->buffer.pointer += 2) : \
IS_BREAK(parser->buffer) ? \
(parser->mark.index ++, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread --, \
parser->buffer.pointer += WIDTH(parser->buffer)) : 0)
/*
* Copy a character to a string buffer and advance pointers.
*/
#define READ(parser,string) \
(STRING_EXTEND(parser,string) ? \
(COPY(string,parser->buffer), \
parser->mark.index ++, \
parser->mark.column ++, \
parser->unread --, \
1) : 0)
/*
* Copy a line break character to a string buffer and advance pointers.
*/
#define READ_LINE(parser,string) \
(STRING_EXTEND(parser,string) ? \
(((CHECK_AT(parser->buffer,'\r',0) \
&& CHECK_AT(parser->buffer,'\n',1)) ? /* CR LF -> LF */ \
(*((string).pointer++) = (yaml_char_t) '\n', \
parser->buffer.pointer += 2, \
parser->mark.index += 2, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread -= 2) : \
(CHECK_AT(parser->buffer,'\r',0) \
|| CHECK_AT(parser->buffer,'\n',0)) ? /* CR|LF -> LF */ \
(*((string).pointer++) = (yaml_char_t) '\n', \
parser->buffer.pointer ++, \
parser->mark.index ++, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread --) : \
(CHECK_AT(parser->buffer,'\xC2',0) \
&& CHECK_AT(parser->buffer,'\x85',1)) ? /* NEL -> LF */ \
(*((string).pointer++) = (yaml_char_t) '\n', \
parser->buffer.pointer += 2, \
parser->mark.index ++, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread --) : \
(CHECK_AT(parser->buffer,'\xE2',0) && \
CHECK_AT(parser->buffer,'\x80',1) && \
(CHECK_AT(parser->buffer,'\xA8',2) || \
CHECK_AT(parser->buffer,'\xA9',2))) ? /* LS|PS -> LS|PS */ \
(*((string).pointer++) = *(parser->buffer.pointer++), \
*((string).pointer++) = *(parser->buffer.pointer++), \
*((string).pointer++) = *(parser->buffer.pointer++), \
parser->mark.index ++, \
parser->mark.column = 0, \
parser->mark.line ++, \
parser->unread --) : 0), \
1) : 0)
/*
* Public API declarations.
*/
YAML_DECLARE(int)
yaml_parser_scan(yaml_parser_t *parser, yaml_token_t *token);
/*
* Error handling.
*/
static int
yaml_parser_set_scanner_error(yaml_parser_t *parser, const char *context,
yaml_mark_t context_mark, const char *problem);
/*
* High-level token API.
*/
YAML_DECLARE(int)
yaml_parser_fetch_more_tokens(yaml_parser_t *parser);
static int
yaml_parser_fetch_next_token(yaml_parser_t *parser);
/*
* Potential simple keys.
*/
static int
yaml_parser_stale_simple_keys(yaml_parser_t *parser);
static int
yaml_parser_save_simple_key(yaml_parser_t *parser);
static int
yaml_parser_remove_simple_key(yaml_parser_t *parser);
static int
yaml_parser_increase_flow_level(yaml_parser_t *parser);
static int
yaml_parser_decrease_flow_level(yaml_parser_t *parser);
/*
* Indentation treatment.
*/
static int
yaml_parser_roll_indent(yaml_parser_t *parser, ptrdiff_t column,
ptrdiff_t number, yaml_token_type_t type, yaml_mark_t mark);
static int
yaml_parser_unroll_indent(yaml_parser_t *parser, ptrdiff_t column);
/*
* Token fetchers.
*/
static int
yaml_parser_fetch_stream_start(yaml_parser_t *parser);
static int
yaml_parser_fetch_stream_end(yaml_parser_t *parser);
static int
yaml_parser_fetch_directive(yaml_parser_t *parser);
static int
yaml_parser_fetch_document_indicator(yaml_parser_t *parser,
yaml_token_type_t type);
static int
yaml_parser_fetch_flow_collection_start(yaml_parser_t *parser,
yaml_token_type_t type);
static int
yaml_parser_fetch_flow_collection_end(yaml_parser_t *parser,
yaml_token_type_t type);
static int
yaml_parser_fetch_flow_entry(yaml_parser_t *parser);
static int
yaml_parser_fetch_block_entry(yaml_parser_t *parser);
static int
yaml_parser_fetch_key(yaml_parser_t *parser);
static int
yaml_parser_fetch_value(yaml_parser_t *parser);
static int
yaml_parser_fetch_anchor(yaml_parser_t *parser, yaml_token_type_t type);
static int
yaml_parser_fetch_tag(yaml_parser_t *parser);
static int
yaml_parser_fetch_block_scalar(yaml_parser_t *parser, int literal);
static int
yaml_parser_fetch_flow_scalar(yaml_parser_t *parser, int single);
static int
yaml_parser_fetch_plain_scalar(yaml_parser_t *parser);
/*
* Token scanners.
*/
static int
yaml_parser_scan_to_next_token(yaml_parser_t *parser);
static int
yaml_parser_scan_directive(yaml_parser_t *parser, yaml_token_t *token);
static int
yaml_parser_scan_directive_name(yaml_parser_t *parser,
yaml_mark_t start_mark, yaml_char_t **name);
static int
yaml_parser_scan_version_directive_value(yaml_parser_t *parser,
yaml_mark_t start_mark, int *major, int *minor);
static int
yaml_parser_scan_version_directive_number(yaml_parser_t *parser,
yaml_mark_t start_mark, int *number);
static int
yaml_parser_scan_tag_directive_value(yaml_parser_t *parser,
yaml_mark_t mark, yaml_char_t **handle, yaml_char_t **prefix);
static int
yaml_parser_scan_anchor(yaml_parser_t *parser, yaml_token_t *token,
yaml_token_type_t type);
static int
yaml_parser_scan_tag(yaml_parser_t *parser, yaml_token_t *token);
static int
yaml_parser_scan_tag_handle(yaml_parser_t *parser, int directive,
yaml_mark_t start_mark, yaml_char_t **handle);
static int
yaml_parser_scan_tag_uri(yaml_parser_t *parser, int directive,
yaml_char_t *head, yaml_mark_t start_mark, yaml_char_t **uri);
static int
yaml_parser_scan_uri_escapes(yaml_parser_t *parser, int directive,
yaml_mark_t start_mark, yaml_string_t *string);
static int
yaml_parser_scan_block_scalar(yaml_parser_t *parser, yaml_token_t *token,
int literal);
static int
yaml_parser_scan_block_scalar_breaks(yaml_parser_t *parser,
int *indent, yaml_string_t *breaks,
yaml_mark_t start_mark, yaml_mark_t *end_mark);
static int
yaml_parser_scan_flow_scalar(yaml_parser_t *parser, yaml_token_t *token,
int single);
static int
yaml_parser_scan_plain_scalar(yaml_parser_t *parser, yaml_token_t *token);
/*
* Get the next token.
*/
YAML_DECLARE(int)
yaml_parser_scan(yaml_parser_t *parser, yaml_token_t *token)
{
assert(parser); /* Non-NULL parser object is expected. */
assert(token); /* Non-NULL token object is expected. */
/* Erase the token object. */
memset(token, 0, sizeof(yaml_token_t));
/* No tokens after STREAM-END or error. */
if (parser->stream_end_produced || parser->error) {
return 1;
}
/* Ensure that the tokens queue contains enough tokens. */
if (!parser->token_available) {
if (!yaml_parser_fetch_more_tokens(parser))
return 0;
}
/* Fetch the next token from the queue. */
*token = DEQUEUE(parser, parser->tokens);
parser->token_available = 0;
parser->tokens_parsed ++;
if (token->type == YAML_STREAM_END_TOKEN) {
parser->stream_end_produced = 1;
}
return 1;
}
/*
* Set the scanner error and return 0.
*/
static int
yaml_parser_set_scanner_error(yaml_parser_t *parser, const char *context,
yaml_mark_t context_mark, const char *problem)
{
parser->error = YAML_SCANNER_ERROR;
parser->context = context;
parser->context_mark = context_mark;
parser->problem = problem;
parser->problem_mark = parser->mark;
return 0;
}
/*
* Ensure that the tokens queue contains at least one token which can be
* returned to the Parser.
*/
YAML_DECLARE(int)
yaml_parser_fetch_more_tokens(yaml_parser_t *parser)
{
int need_more_tokens;
/* While we need more tokens to fetch, do it. */
while (1)
{
/*
* Check if we really need to fetch more tokens.
*/
need_more_tokens = 0;
if (parser->tokens.head == parser->tokens.tail)
{
/* Queue is empty. */
need_more_tokens = 1;
}
else
{
yaml_simple_key_t *simple_key;
/* Check if any potential simple key may occupy the head position. */
if (!yaml_parser_stale_simple_keys(parser))
return 0;
for (simple_key = parser->simple_keys.start;
simple_key != parser->simple_keys.top; simple_key++) {
if (simple_key->possible
&& simple_key->token_number == parser->tokens_parsed) {
need_more_tokens = 1;
break;
}
}
}
/* We are finished. */
if (!need_more_tokens)
break;
/* Fetch the next token. */
if (!yaml_parser_fetch_next_token(parser))
return 0;
}
parser->token_available = 1;
return 1;
}
/*
* The dispatcher for token fetchers.
*/
static int
yaml_parser_fetch_next_token(yaml_parser_t *parser)
{
/* Ensure that the buffer is initialized. */
if (!CACHE(parser, 1))
return 0;
/* Check if we just started scanning. Fetch STREAM-START then. */
if (!parser->stream_start_produced)
return yaml_parser_fetch_stream_start(parser);
/* Eat whitespaces and comments until we reach the next token. */
if (!yaml_parser_scan_to_next_token(parser))
return 0;
/* Remove obsolete potential simple keys. */
if (!yaml_parser_stale_simple_keys(parser))
return 0;
/* Check the indentation level against the current column. */
if (!yaml_parser_unroll_indent(parser, parser->mark.column))
return 0;
/*
* Ensure that the buffer contains at least 4 characters. 4 is the length
* of the longest indicators ('--- ' and '... ').
*/
if (!CACHE(parser, 4))
return 0;
/* Is it the end of the stream? */
if (IS_Z(parser->buffer))
return yaml_parser_fetch_stream_end(parser);
/* Is it a directive? */
if (parser->mark.column == 0 && CHECK(parser->buffer, '%'))
return yaml_parser_fetch_directive(parser);
/* Is it the document start indicator? */
if (parser->mark.column == 0
&& CHECK_AT(parser->buffer, '-', 0)
&& CHECK_AT(parser->buffer, '-', 1)
&& CHECK_AT(parser->buffer, '-', 2)
&& IS_BLANKZ_AT(parser->buffer, 3))
return yaml_parser_fetch_document_indicator(parser,
YAML_DOCUMENT_START_TOKEN);
/* Is it the document end indicator? */
if (parser->mark.column == 0
&& CHECK_AT(parser->buffer, '.', 0)
&& CHECK_AT(parser->buffer, '.', 1)
&& CHECK_AT(parser->buffer, '.', 2)
&& IS_BLANKZ_AT(parser->buffer, 3))
return yaml_parser_fetch_document_indicator(parser,
YAML_DOCUMENT_END_TOKEN);
/* Is it the flow sequence start indicator? */
if (CHECK(parser->buffer, '['))
return yaml_parser_fetch_flow_collection_start(parser,
YAML_FLOW_SEQUENCE_START_TOKEN);
/* Is it the flow mapping start indicator? */
if (CHECK(parser->buffer, '{'))
return yaml_parser_fetch_flow_collection_start(parser,
YAML_FLOW_MAPPING_START_TOKEN);
/* Is it the flow sequence end indicator? */
if (CHECK(parser->buffer, ']'))
return yaml_parser_fetch_flow_collection_end(parser,
YAML_FLOW_SEQUENCE_END_TOKEN);
/* Is it the flow mapping end indicator? */
if (CHECK(parser->buffer, '}'))
return yaml_parser_fetch_flow_collection_end(parser,
YAML_FLOW_MAPPING_END_TOKEN);
/* Is it the flow entry indicator? */
if (CHECK(parser->buffer, ','))
return yaml_parser_fetch_flow_entry(parser);
/* Is it the block entry indicator? */
if (CHECK(parser->buffer, '-') && IS_BLANKZ_AT(parser->buffer, 1))
return yaml_parser_fetch_block_entry(parser);
/* Is it the key indicator? */
if (CHECK(parser->buffer, '?')
&& (parser->flow_level || IS_BLANKZ_AT(parser->buffer, 1)))
return yaml_parser_fetch_key(parser);
/* Is it the value indicator? */
if (CHECK(parser->buffer, ':')
&& (parser->flow_level || IS_BLANKZ_AT(parser->buffer, 1)))
return yaml_parser_fetch_value(parser);
/* Is it an alias? */
if (CHECK(parser->buffer, '*'))
return yaml_parser_fetch_anchor(parser, YAML_ALIAS_TOKEN);
/* Is it an anchor? */
if (CHECK(parser->buffer, '&'))
return yaml_parser_fetch_anchor(parser, YAML_ANCHOR_TOKEN);
/* Is it a tag? */
if (CHECK(parser->buffer, '!'))
return yaml_parser_fetch_tag(parser);
/* Is it a literal scalar? */
if (CHECK(parser->buffer, '|') && !parser->flow_level)
return yaml_parser_fetch_block_scalar(parser, 1);
/* Is it a folded scalar? */
if (CHECK(parser->buffer, '>') && !parser->flow_level)
return yaml_parser_fetch_block_scalar(parser, 0);
/* Is it a single-quoted scalar? */
if (CHECK(parser->buffer, '\''))
return yaml_parser_fetch_flow_scalar(parser, 1);
/* Is it a double-quoted scalar? */
if (CHECK(parser->buffer, '"'))
return yaml_parser_fetch_flow_scalar(parser, 0);
/*
* Is it a plain scalar?
*
* A plain scalar may start with any non-blank characters except
*
* '-', '?', ':', ',', '[', ']', '{', '}',
* '#', '&', '*', '!', '|', '>', '\'', '\"',
* '%', '@', '`'.
*
* In the block context (and, for the '-' indicator, in the flow context
* too), it may also start with the characters
*
* '-', '?', ':'
*
* if it is followed by a non-space character.
*
* The last rule is more restrictive than the specification requires.
*/
if (!(IS_BLANKZ(parser->buffer) || CHECK(parser->buffer, '-')
|| CHECK(parser->buffer, '?') || CHECK(parser->buffer, ':')
|| CHECK(parser->buffer, ',') || CHECK(parser->buffer, '[')
|| CHECK(parser->buffer, ']') || CHECK(parser->buffer, '{')
|| CHECK(parser->buffer, '}') || CHECK(parser->buffer, '#')
|| CHECK(parser->buffer, '&') || CHECK(parser->buffer, '*')
|| CHECK(parser->buffer, '!') || CHECK(parser->buffer, '|')
|| CHECK(parser->buffer, '>') || CHECK(parser->buffer, '\'')
|| CHECK(parser->buffer, '"') || CHECK(parser->buffer, '%')
|| CHECK(parser->buffer, '@') || CHECK(parser->buffer, '`')) ||
(CHECK(parser->buffer, '-') && !IS_BLANK_AT(parser->buffer, 1)) ||
(!parser->flow_level &&
(CHECK(parser->buffer, '?') || CHECK(parser->buffer, ':'))
&& !IS_BLANKZ_AT(parser->buffer, 1)))
return yaml_parser_fetch_plain_scalar(parser);
/*
* If we don't determine the token type so far, it is an error.
*/
return yaml_parser_set_scanner_error(parser,
"while scanning for the next token", parser->mark,
"found character that cannot start any token");
}
/*
* Check the list of potential simple keys and remove the positions that
* cannot contain simple keys anymore.
*/
static int
yaml_parser_stale_simple_keys(yaml_parser_t *parser)
{
yaml_simple_key_t *simple_key;
/* Check for a potential simple key for each flow level. */
for (simple_key = parser->simple_keys.start;
simple_key != parser->simple_keys.top; simple_key ++)
{
/*
* The specification requires that a simple key
*
* - is limited to a single line,
* - is shorter than 1024 characters.
*/
if (simple_key->possible
&& (simple_key->mark.line < parser->mark.line
|| simple_key->mark.index+1024 < parser->mark.index)) {
/* Check if the potential simple key to be removed is required. */
if (simple_key->required) {
return yaml_parser_set_scanner_error(parser,
"while scanning a simple key", simple_key->mark,
"could not find expected ':'");
}
simple_key->possible = 0;
}
}
return 1;
}
/*
* Check if a simple key may start at the current position and add it if
* needed.
*/
static int
yaml_parser_save_simple_key(yaml_parser_t *parser)
{
/*
* A simple key is required at the current position if the scanner is in
* the block context and the current column coincides with the indentation
* level.
*/
int required = (!parser->flow_level
&& parser->indent == (ptrdiff_t)parser->mark.column);
/*
* A simple key is required only when it is the first token in the current
* line. Therefore it is always allowed. But we add a check anyway.
*/
assert(parser->simple_key_allowed || !required); /* Impossible. */
/*
* If the current position may start a simple key, save it.
*/
if (parser->simple_key_allowed)
{
yaml_simple_key_t simple_key;
simple_key.possible = 1;
simple_key.required = required;
simple_key.token_number =
parser->tokens_parsed + (parser->tokens.tail - parser->tokens.head);
simple_key.mark = parser->mark;
if (!yaml_parser_remove_simple_key(parser)) return 0;
*(parser->simple_keys.top-1) = simple_key;
}
return 1;
}
/*
* Remove a potential simple key at the current flow level.
*/
static int
yaml_parser_remove_simple_key(yaml_parser_t *parser)
{
yaml_simple_key_t *simple_key = parser->simple_keys.top-1;
if (simple_key->possible)
{
/* If the key is required, it is an error. */
if (simple_key->required) {
return yaml_parser_set_scanner_error(parser,
"while scanning a simple key", simple_key->mark,
"could not find expected ':'");
}
}
/* Remove the key from the stack. */
simple_key->possible = 0;
return 1;
}
/*
* Increase the flow level and resize the simple key list if needed.
*/
static int
yaml_parser_increase_flow_level(yaml_parser_t *parser)
{
yaml_simple_key_t empty_simple_key = { 0, 0, 0, { 0, 0, 0 } };
/* Reset the simple key on the next level. */
if (!PUSH(parser, parser->simple_keys, empty_simple_key))
return 0;
/* Increase the flow level. */
if (parser->flow_level == INT_MAX) {
parser->error = YAML_MEMORY_ERROR;
return 0;
}
parser->flow_level++;
return 1;
}
/*
* Decrease the flow level.
*/
static int
yaml_parser_decrease_flow_level(yaml_parser_t *parser)
{
if (parser->flow_level) {
parser->flow_level --;
(void)POP(parser, parser->simple_keys);
}
return 1;
}
/*
* Push the current indentation level to the stack and set the new level
* the current column is greater than the indentation level. In this case,
* append or insert the specified token into the token queue.
*
*/
static int
yaml_parser_roll_indent(yaml_parser_t *parser, ptrdiff_t column,
ptrdiff_t number, yaml_token_type_t type, yaml_mark_t mark)
{
yaml_token_t token;
/* In the flow context, do nothing. */
if (parser->flow_level)
return 1;
if (parser->indent < column)
{
/*
* Push the current indentation level to the stack and set the new
* indentation level.
*/
if (!PUSH(parser, parser->indents, parser->indent))
return 0;
#if PTRDIFF_MAX > INT_MAX
if (column > INT_MAX) {
parser->error = YAML_MEMORY_ERROR;
return 0;
}
#endif
parser->indent = (int)column;
/* Create a token and insert it into the queue. */
TOKEN_INIT(token, type, mark, mark);
if (number == -1) {
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
}
else {
if (!QUEUE_INSERT(parser,
parser->tokens, number - parser->tokens_parsed, token))
return 0;
}
}
return 1;
}
/*
* Pop indentation levels from the indents stack until the current level
* becomes less or equal to the column. For each intendation level, append
* the BLOCK-END token.
*/
static int
yaml_parser_unroll_indent(yaml_parser_t *parser, ptrdiff_t column)
{
yaml_token_t token;
/* In the flow context, do nothing. */
if (parser->flow_level)
return 1;
/* Loop through the intendation levels in the stack. */
while (parser->indent > column)
{
/* Create a token and append it to the queue. */
TOKEN_INIT(token, YAML_BLOCK_END_TOKEN, parser->mark, parser->mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
/* Pop the indentation level. */
parser->indent = POP(parser, parser->indents);
}
return 1;
}
/*
* Initialize the scanner and produce the STREAM-START token.
*/
static int
yaml_parser_fetch_stream_start(yaml_parser_t *parser)
{
yaml_simple_key_t simple_key = { 0, 0, 0, { 0, 0, 0 } };
yaml_token_t token;
/* Set the initial indentation. */
parser->indent = -1;
/* Initialize the simple key stack. */
if (!PUSH(parser, parser->simple_keys, simple_key))
return 0;
/* A simple key is allowed at the beginning of the stream. */
parser->simple_key_allowed = 1;
/* We have started. */
parser->stream_start_produced = 1;
/* Create the STREAM-START token and append it to the queue. */
STREAM_START_TOKEN_INIT(token, parser->encoding,
parser->mark, parser->mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the STREAM-END token and shut down the scanner.
*/
static int
yaml_parser_fetch_stream_end(yaml_parser_t *parser)
{
yaml_token_t token;
/* Force new line. */
if (parser->mark.column != 0) {
parser->mark.column = 0;
parser->mark.line ++;
}
/* Reset the indentation level. */
if (!yaml_parser_unroll_indent(parser, -1))
return 0;
/* Reset simple keys. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
parser->simple_key_allowed = 0;
/* Create the STREAM-END token and append it to the queue. */
STREAM_END_TOKEN_INIT(token, parser->mark, parser->mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce a VERSION-DIRECTIVE or TAG-DIRECTIVE token.
*/
static int
yaml_parser_fetch_directive(yaml_parser_t *parser)
{
yaml_token_t token;
/* Reset the indentation level. */
if (!yaml_parser_unroll_indent(parser, -1))
return 0;
/* Reset simple keys. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
parser->simple_key_allowed = 0;
/* Create the YAML-DIRECTIVE or TAG-DIRECTIVE token. */
if (!yaml_parser_scan_directive(parser, &token))
return 0;
/* Append the token to the queue. */
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Produce the DOCUMENT-START or DOCUMENT-END token.
*/
static int
yaml_parser_fetch_document_indicator(yaml_parser_t *parser,
yaml_token_type_t type)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* Reset the indentation level. */
if (!yaml_parser_unroll_indent(parser, -1))
return 0;
/* Reset simple keys. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
parser->simple_key_allowed = 0;
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
SKIP(parser);
SKIP(parser);
end_mark = parser->mark;
/* Create the DOCUMENT-START or DOCUMENT-END token. */
TOKEN_INIT(token, type, start_mark, end_mark);
/* Append the token to the queue. */
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
*/
static int
yaml_parser_fetch_flow_collection_start(yaml_parser_t *parser,
yaml_token_type_t type)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* The indicators '[' and '{' may start a simple key. */
if (!yaml_parser_save_simple_key(parser))
return 0;
/* Increase the flow level. */
if (!yaml_parser_increase_flow_level(parser))
return 0;
/* A simple key may follow the indicators '[' and '{'. */
parser->simple_key_allowed = 1;
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the FLOW-SEQUENCE-START of FLOW-MAPPING-START token. */
TOKEN_INIT(token, type, start_mark, end_mark);
/* Append the token to the queue. */
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the FLOW-SEQUENCE-END or FLOW-MAPPING-END token.
*/
static int
yaml_parser_fetch_flow_collection_end(yaml_parser_t *parser,
yaml_token_type_t type)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* Reset any potential simple key on the current flow level. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
/* Decrease the flow level. */
if (!yaml_parser_decrease_flow_level(parser))
return 0;
/* No simple keys after the indicators ']' and '}'. */
parser->simple_key_allowed = 0;
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the FLOW-SEQUENCE-END of FLOW-MAPPING-END token. */
TOKEN_INIT(token, type, start_mark, end_mark);
/* Append the token to the queue. */
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the FLOW-ENTRY token.
*/
static int
yaml_parser_fetch_flow_entry(yaml_parser_t *parser)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* Reset any potential simple keys on the current flow level. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
/* Simple keys are allowed after ','. */
parser->simple_key_allowed = 1;
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the FLOW-ENTRY token and append it to the queue. */
TOKEN_INIT(token, YAML_FLOW_ENTRY_TOKEN, start_mark, end_mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the BLOCK-ENTRY token.
*/
static int
yaml_parser_fetch_block_entry(yaml_parser_t *parser)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* Check if the scanner is in the block context. */
if (!parser->flow_level)
{
/* Check if we are allowed to start a new entry. */
if (!parser->simple_key_allowed) {
return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
"block sequence entries are not allowed in this context");
}
/* Add the BLOCK-SEQUENCE-START token if needed. */
if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
YAML_BLOCK_SEQUENCE_START_TOKEN, parser->mark))
return 0;
}
else
{
/*
* It is an error for the '-' indicator to occur in the flow context,
* but we let the Parser detect and report about it because the Parser
* is able to point to the context.
*/
}
/* Reset any potential simple keys on the current flow level. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
/* Simple keys are allowed after '-'. */
parser->simple_key_allowed = 1;
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the BLOCK-ENTRY token and append it to the queue. */
TOKEN_INIT(token, YAML_BLOCK_ENTRY_TOKEN, start_mark, end_mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the KEY token.
*/
static int
yaml_parser_fetch_key(yaml_parser_t *parser)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
/* In the block context, additional checks are required. */
if (!parser->flow_level)
{
/* Check if we are allowed to start a new key (not nessesary simple). */
if (!parser->simple_key_allowed) {
return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
"mapping keys are not allowed in this context");
}
/* Add the BLOCK-MAPPING-START token if needed. */
if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
YAML_BLOCK_MAPPING_START_TOKEN, parser->mark))
return 0;
}
/* Reset any potential simple keys on the current flow level. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
/* Simple keys are allowed after '?' in the block context. */
parser->simple_key_allowed = (!parser->flow_level);
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the KEY token and append it to the queue. */
TOKEN_INIT(token, YAML_KEY_TOKEN, start_mark, end_mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the VALUE token.
*/
static int
yaml_parser_fetch_value(yaml_parser_t *parser)
{
yaml_mark_t start_mark, end_mark;
yaml_token_t token;
yaml_simple_key_t *simple_key = parser->simple_keys.top-1;
/* Have we found a simple key? */
if (simple_key->possible)
{
/* Create the KEY token and insert it into the queue. */
TOKEN_INIT(token, YAML_KEY_TOKEN, simple_key->mark, simple_key->mark);
if (!QUEUE_INSERT(parser, parser->tokens,
simple_key->token_number - parser->tokens_parsed, token))
return 0;
/* In the block context, we may need to add the BLOCK-MAPPING-START token. */
if (!yaml_parser_roll_indent(parser, simple_key->mark.column,
simple_key->token_number,
YAML_BLOCK_MAPPING_START_TOKEN, simple_key->mark))
return 0;
/* Remove the simple key. */
simple_key->possible = 0;
/* A simple key cannot follow another simple key. */
parser->simple_key_allowed = 0;
}
else
{
/* The ':' indicator follows a complex key. */
/* In the block context, extra checks are required. */
if (!parser->flow_level)
{
/* Check if we are allowed to start a complex value. */
if (!parser->simple_key_allowed) {
return yaml_parser_set_scanner_error(parser, NULL, parser->mark,
"mapping values are not allowed in this context");
}
/* Add the BLOCK-MAPPING-START token if needed. */
if (!yaml_parser_roll_indent(parser, parser->mark.column, -1,
YAML_BLOCK_MAPPING_START_TOKEN, parser->mark))
return 0;
}
/* Simple keys after ':' are allowed in the block context. */
parser->simple_key_allowed = (!parser->flow_level);
}
/* Consume the token. */
start_mark = parser->mark;
SKIP(parser);
end_mark = parser->mark;
/* Create the VALUE token and append it to the queue. */
TOKEN_INIT(token, YAML_VALUE_TOKEN, start_mark, end_mark);
if (!ENQUEUE(parser, parser->tokens, token))
return 0;
return 1;
}
/*
* Produce the ALIAS or ANCHOR token.
*/
static int
yaml_parser_fetch_anchor(yaml_parser_t *parser, yaml_token_type_t type)
{
yaml_token_t token;
/* An anchor or an alias could be a simple key. */
if (!yaml_parser_save_simple_key(parser))
return 0;
/* A simple key cannot follow an anchor or an alias. */
parser->simple_key_allowed = 0;
/* Create the ALIAS or ANCHOR token and append it to the queue. */
if (!yaml_parser_scan_anchor(parser, &token, type))
return 0;
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Produce the TAG token.
*/
static int
yaml_parser_fetch_tag(yaml_parser_t *parser)
{
yaml_token_t token;
/* A tag could be a simple key. */
if (!yaml_parser_save_simple_key(parser))
return 0;
/* A simple key cannot follow a tag. */
parser->simple_key_allowed = 0;
/* Create the TAG token and append it to the queue. */
if (!yaml_parser_scan_tag(parser, &token))
return 0;
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Produce the SCALAR(...,literal) or SCALAR(...,folded) tokens.
*/
static int
yaml_parser_fetch_block_scalar(yaml_parser_t *parser, int literal)
{
yaml_token_t token;
/* Remove any potential simple keys. */
if (!yaml_parser_remove_simple_key(parser))
return 0;
/* A simple key may follow a block scalar. */
parser->simple_key_allowed = 1;
/* Create the SCALAR token and append it to the queue. */
if (!yaml_parser_scan_block_scalar(parser, &token, literal))
return 0;
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Produce the SCALAR(...,single-quoted) or SCALAR(...,double-quoted) tokens.
*/
static int
yaml_parser_fetch_flow_scalar(yaml_parser_t *parser, int single)
{
yaml_token_t token;
/* A plain scalar could be a simple key. */
if (!yaml_parser_save_simple_key(parser))
return 0;
/* A simple key cannot follow a flow scalar. */
parser->simple_key_allowed = 0;
/* Create the SCALAR token and append it to the queue. */
if (!yaml_parser_scan_flow_scalar(parser, &token, single))
return 0;
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Produce the SCALAR(...,plain) token.
*/
static int
yaml_parser_fetch_plain_scalar(yaml_parser_t *parser)
{
yaml_token_t token;
/* A plain scalar could be a simple key. */
if (!yaml_parser_save_simple_key(parser))
return 0;
/* A simple key cannot follow a flow scalar. */
parser->simple_key_allowed = 0;
/* Create the SCALAR token and append it to the queue. */
if (!yaml_parser_scan_plain_scalar(parser, &token))
return 0;
if (!ENQUEUE(parser, parser->tokens, token)) {
yaml_token_delete(&token);
return 0;
}
return 1;
}
/*
* Eat whitespaces and comments until the next token is found.
*/
static int
yaml_parser_scan_to_next_token(yaml_parser_t *parser)
{
/* Until the next token is not found. */
while (1)
{
/* Allow the BOM mark to start a line. */
if (!CACHE(parser, 1)) return 0;
if (parser->mark.column == 0 && IS_BOM(parser->buffer))
SKIP(parser);
/*
* Eat whitespaces.
*
* Tabs are allowed:
*
* - in the flow context;
* - in the block context, but not at the beginning of the line or
* after '-', '?', or ':' (complex value).
*/
if (!CACHE(parser, 1)) return 0;
while (CHECK(parser->buffer,' ') ||
((parser->flow_level || !parser->simple_key_allowed) &&
CHECK(parser->buffer, '\t'))) {
SKIP(parser);
if (!CACHE(parser, 1)) return 0;
}
/* Eat a comment until a line break. */
if (CHECK(parser->buffer, '#')) {
while (!IS_BREAKZ(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) return 0;
}
}
/* If it is a line break, eat it. */
if (IS_BREAK(parser->buffer))
{
if (!CACHE(parser, 2)) return 0;
SKIP_LINE(parser);
/* In the block context, a new line may start a simple key. */
if (!parser->flow_level) {
parser->simple_key_allowed = 1;
}
}
else
{
/* We have found a token. */
break;
}
}
return 1;
}
/*
* Scan a YAML-DIRECTIVE or TAG-DIRECTIVE token.
*
* Scope:
* %YAML 1.1 # a comment \n
* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
* %TAG !yaml! tag:yaml.org,2002: \n
* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*/
int
yaml_parser_scan_directive(yaml_parser_t *parser, yaml_token_t *token)
{
yaml_mark_t start_mark, end_mark;
yaml_char_t *name = NULL;
int major, minor;
yaml_char_t *handle = NULL, *prefix = NULL;
/* Eat '%'. */
start_mark = parser->mark;
SKIP(parser);
/* Scan the directive name. */
if (!yaml_parser_scan_directive_name(parser, start_mark, &name))
goto error;
/* Is it a YAML directive? */
if (strcmp((char *)name, "YAML") == 0)
{
/* Scan the VERSION directive value. */
if (!yaml_parser_scan_version_directive_value(parser, start_mark,
&major, &minor))
goto error;
end_mark = parser->mark;
/* Create a VERSION-DIRECTIVE token. */
VERSION_DIRECTIVE_TOKEN_INIT(*token, major, minor,
start_mark, end_mark);
}
/* Is it a TAG directive? */
else if (strcmp((char *)name, "TAG") == 0)
{
/* Scan the TAG directive value. */
if (!yaml_parser_scan_tag_directive_value(parser, start_mark,
&handle, &prefix))
goto error;
end_mark = parser->mark;
/* Create a TAG-DIRECTIVE token. */
TAG_DIRECTIVE_TOKEN_INIT(*token, handle, prefix,
start_mark, end_mark);
}
/* Unknown directive. */
else
{
yaml_parser_set_scanner_error(parser, "while scanning a directive",
start_mark, "found uknown directive name");
goto error;
}
/* Eat the rest of the line including any comments. */
if (!CACHE(parser, 1)) goto error;
while (IS_BLANK(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
if (CHECK(parser->buffer, '#')) {
while (!IS_BREAKZ(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
}
/* Check if we are at the end of the line. */
if (!IS_BREAKZ(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a directive",
start_mark, "did not find expected comment or line break");
goto error;
}
/* Eat a line break. */
if (IS_BREAK(parser->buffer)) {
if (!CACHE(parser, 2)) goto error;
SKIP_LINE(parser);
}
yaml_free(name);
return 1;
error:
yaml_free(prefix);
yaml_free(handle);
yaml_free(name);
return 0;
}
/*
* Scan the directive name.
*
* Scope:
* %YAML 1.1 # a comment \n
* ^^^^
* %TAG !yaml! tag:yaml.org,2002: \n
* ^^^
*/
static int
yaml_parser_scan_directive_name(yaml_parser_t *parser,
yaml_mark_t start_mark, yaml_char_t **name)
{
yaml_string_t string = NULL_STRING;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
/* Consume the directive name. */
if (!CACHE(parser, 1)) goto error;
while (IS_ALPHA(parser->buffer))
{
if (!READ(parser, string)) goto error;
if (!CACHE(parser, 1)) goto error;
}
/* Check if the name is empty. */
if (string.start == string.pointer) {
yaml_parser_set_scanner_error(parser, "while scanning a directive",
start_mark, "could not find expected directive name");
goto error;
}
/* Check for an blank character after the name. */
if (!IS_BLANKZ(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a directive",
start_mark, "found unexpected non-alphabetical character");
goto error;
}
*name = string.start;
return 1;
error:
STRING_DEL(parser, string);
return 0;
}
/*
* Scan the value of VERSION-DIRECTIVE.
*
* Scope:
* %YAML 1.1 # a comment \n
* ^^^^^^
*/
static int
yaml_parser_scan_version_directive_value(yaml_parser_t *parser,
yaml_mark_t start_mark, int *major, int *minor)
{
/* Eat whitespaces. */
if (!CACHE(parser, 1)) return 0;
while (IS_BLANK(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) return 0;
}
/* Consume the major version number. */
if (!yaml_parser_scan_version_directive_number(parser, start_mark, major))
return 0;
/* Eat '.'. */
if (!CHECK(parser->buffer, '.')) {
return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
start_mark, "did not find expected digit or '.' character");
}
SKIP(parser);
/* Consume the minor version number. */
if (!yaml_parser_scan_version_directive_number(parser, start_mark, minor))
return 0;
return 1;
}
#define MAX_NUMBER_LENGTH 9
/*
* Scan the version number of VERSION-DIRECTIVE.
*
* Scope:
* %YAML 1.1 # a comment \n
* ^
* %YAML 1.1 # a comment \n
* ^
*/
static int
yaml_parser_scan_version_directive_number(yaml_parser_t *parser,
yaml_mark_t start_mark, int *number)
{
int value = 0;
size_t length = 0;
/* Repeat while the next character is digit. */
if (!CACHE(parser, 1)) return 0;
while (IS_DIGIT(parser->buffer))
{
/* Check if the number is too long. */
if (++length > MAX_NUMBER_LENGTH) {
return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
start_mark, "found extremely long version number");
}
value = value*10 + AS_DIGIT(parser->buffer);
SKIP(parser);
if (!CACHE(parser, 1)) return 0;
}
/* Check if the number was present. */
if (!length) {
return yaml_parser_set_scanner_error(parser, "while scanning a %YAML directive",
start_mark, "did not find expected version number");
}
*number = value;
return 1;
}
/*
* Scan the value of a TAG-DIRECTIVE token.
*
* Scope:
* %TAG !yaml! tag:yaml.org,2002: \n
* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*/
static int
yaml_parser_scan_tag_directive_value(yaml_parser_t *parser,
yaml_mark_t start_mark, yaml_char_t **handle, yaml_char_t **prefix)
{
yaml_char_t *handle_value = NULL;
yaml_char_t *prefix_value = NULL;
/* Eat whitespaces. */
if (!CACHE(parser, 1)) goto error;
while (IS_BLANK(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
/* Scan a handle. */
if (!yaml_parser_scan_tag_handle(parser, 1, start_mark, &handle_value))
goto error;
/* Expect a whitespace. */
if (!CACHE(parser, 1)) goto error;
if (!IS_BLANK(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
start_mark, "did not find expected whitespace");
goto error;
}
/* Eat whitespaces. */
while (IS_BLANK(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
/* Scan a prefix. */
if (!yaml_parser_scan_tag_uri(parser, 1, NULL, start_mark, &prefix_value))
goto error;
/* Expect a whitespace or line break. */
if (!CACHE(parser, 1)) goto error;
if (!IS_BLANKZ(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a %TAG directive",
start_mark, "did not find expected whitespace or line break");
goto error;
}
*handle = handle_value;
*prefix = prefix_value;
return 1;
error:
yaml_free(handle_value);
yaml_free(prefix_value);
return 0;
}
static int
yaml_parser_scan_anchor(yaml_parser_t *parser, yaml_token_t *token,
yaml_token_type_t type)
{
int length = 0;
yaml_mark_t start_mark, end_mark;
yaml_string_t string = NULL_STRING;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
/* Eat the indicator character. */
start_mark = parser->mark;
SKIP(parser);
/* Consume the value. */
if (!CACHE(parser, 1)) goto error;
while (IS_ALPHA(parser->buffer)) {
if (!READ(parser, string)) goto error;
if (!CACHE(parser, 1)) goto error;
length ++;
}
end_mark = parser->mark;
/*
* Check if length of the anchor is greater than 0 and it is followed by
* a whitespace character or one of the indicators:
*
* '?', ':', ',', ']', '}', '%', '@', '`'.
*/
if (!length || !(IS_BLANKZ(parser->buffer) || CHECK(parser->buffer, '?')
|| CHECK(parser->buffer, ':') || CHECK(parser->buffer, ',')
|| CHECK(parser->buffer, ']') || CHECK(parser->buffer, '}')
|| CHECK(parser->buffer, '%') || CHECK(parser->buffer, '@')
|| CHECK(parser->buffer, '`'))) {
yaml_parser_set_scanner_error(parser, type == YAML_ANCHOR_TOKEN ?
"while scanning an anchor" : "while scanning an alias", start_mark,
"did not find expected alphabetic or numeric character");
goto error;
}
/* Create a token. */
if (type == YAML_ANCHOR_TOKEN) {
ANCHOR_TOKEN_INIT(*token, string.start, start_mark, end_mark);
}
else {
ALIAS_TOKEN_INIT(*token, string.start, start_mark, end_mark);
}
return 1;
error:
STRING_DEL(parser, string);
return 0;
}
/*
* Scan a TAG token.
*/
static int
yaml_parser_scan_tag(yaml_parser_t *parser, yaml_token_t *token)
{
yaml_char_t *handle = NULL;
yaml_char_t *suffix = NULL;
yaml_mark_t start_mark, end_mark;
start_mark = parser->mark;
/* Check if the tag is in the canonical form. */
if (!CACHE(parser, 2)) goto error;
if (CHECK_AT(parser->buffer, '<', 1))
{
/* Set the handle to '' */
handle = yaml_malloc(1);
if (!handle) goto error;
handle[0] = '\0';
/* Eat '!<' */
SKIP(parser);
SKIP(parser);
/* Consume the tag value. */
if (!yaml_parser_scan_tag_uri(parser, 0, NULL, start_mark, &suffix))
goto error;
/* Check for '>' and eat it. */
if (!CHECK(parser->buffer, '>')) {
yaml_parser_set_scanner_error(parser, "while scanning a tag",
start_mark, "did not find the expected '>'");
goto error;
}
SKIP(parser);
}
else
{
/* The tag has either the '!suffix' or the '!handle!suffix' form. */
/* First, try to scan a handle. */
if (!yaml_parser_scan_tag_handle(parser, 0, start_mark, &handle))
goto error;
/* Check if it is, indeed, handle. */
if (handle[0] == '!' && handle[1] != '\0' && handle[strlen((char *)handle)-1] == '!')
{
/* Scan the suffix now. */
if (!yaml_parser_scan_tag_uri(parser, 0, NULL, start_mark, &suffix))
goto error;
}
else
{
/* It wasn't a handle after all. Scan the rest of the tag. */
if (!yaml_parser_scan_tag_uri(parser, 0, handle, start_mark, &suffix))
goto error;
/* Set the handle to '!'. */
yaml_free(handle);
handle = yaml_malloc(2);
if (!handle) goto error;
handle[0] = '!';
handle[1] = '\0';
/*
* A special case: the '!' tag. Set the handle to '' and the
* suffix to '!'.
*/
if (suffix[0] == '\0') {
yaml_char_t *tmp = handle;
handle = suffix;
suffix = tmp;
}
}
}
/* Check the character which ends the tag. */
if (!CACHE(parser, 1)) goto error;
if (!IS_BLANKZ(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a tag",
start_mark, "did not find expected whitespace or line break");
goto error;
}
end_mark = parser->mark;
/* Create a token. */
TAG_TOKEN_INIT(*token, handle, suffix, start_mark, end_mark);
return 1;
error:
yaml_free(handle);
yaml_free(suffix);
return 0;
}
/*
* Scan a tag handle.
*/
static int
yaml_parser_scan_tag_handle(yaml_parser_t *parser, int directive,
yaml_mark_t start_mark, yaml_char_t **handle)
{
yaml_string_t string = NULL_STRING;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
/* Check the initial '!' character. */
if (!CACHE(parser, 1)) goto error;
if (!CHECK(parser->buffer, '!')) {
yaml_parser_set_scanner_error(parser, directive ?
"while scanning a tag directive" : "while scanning a tag",
start_mark, "did not find expected '!'");
goto error;
}
/* Copy the '!' character. */
if (!READ(parser, string)) goto error;
/* Copy all subsequent alphabetical and numerical characters. */
if (!CACHE(parser, 1)) goto error;
while (IS_ALPHA(parser->buffer))
{
if (!READ(parser, string)) goto error;
if (!CACHE(parser, 1)) goto error;
}
/* Check if the trailing character is '!' and copy it. */
if (CHECK(parser->buffer, '!'))
{
if (!READ(parser, string)) goto error;
}
else
{
/*
* It's either the '!' tag or not really a tag handle. If it's a %TAG
* directive, it's an error. If it's a tag token, it must be a part of
* URI.
*/
if (directive && !(string.start[0] == '!' && string.start[1] == '\0')) {
yaml_parser_set_scanner_error(parser, "while parsing a tag directive",
start_mark, "did not find expected '!'");
goto error;
}
}
*handle = string.start;
return 1;
error:
STRING_DEL(parser, string);
return 0;
}
/*
* Scan a tag.
*/
static int
yaml_parser_scan_tag_uri(yaml_parser_t *parser, int directive,
yaml_char_t *head, yaml_mark_t start_mark, yaml_char_t **uri)
{
size_t length = head ? strlen((char *)head) : 0;
yaml_string_t string = NULL_STRING;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
/* Resize the string to include the head. */
while ((size_t)(string.end - string.start) <= length) {
if (!yaml_string_extend(&string.start, &string.pointer, &string.end)) {
parser->error = YAML_MEMORY_ERROR;
goto error;
}
}
/*
* Copy the head if needed.
*
* Note that we don't copy the leading '!' character.
*/
if (length > 1) {
memcpy(string.start, head+1, length-1);
string.pointer += length-1;
}
/* Scan the tag. */
if (!CACHE(parser, 1)) goto error;
/*
* The set of characters that may appear in URI is as follows:
*
* '0'-'9', 'A'-'Z', 'a'-'z', '_', '-', ';', '/', '?', ':', '@', '&',
* '=', '+', '$', ',', '.', '!', '~', '*', '\'', '(', ')', '[', ']',
* '%'.
*/
while (IS_ALPHA(parser->buffer) || CHECK(parser->buffer, ';')
|| CHECK(parser->buffer, '/') || CHECK(parser->buffer, '?')
|| CHECK(parser->buffer, ':') || CHECK(parser->buffer, '@')
|| CHECK(parser->buffer, '&') || CHECK(parser->buffer, '=')
|| CHECK(parser->buffer, '+') || CHECK(parser->buffer, '$')
|| CHECK(parser->buffer, ',') || CHECK(parser->buffer, '.')
|| CHECK(parser->buffer, '!') || CHECK(parser->buffer, '~')
|| CHECK(parser->buffer, '*') || CHECK(parser->buffer, '\'')
|| CHECK(parser->buffer, '(') || CHECK(parser->buffer, ')')
|| CHECK(parser->buffer, '[') || CHECK(parser->buffer, ']')
|| CHECK(parser->buffer, '%'))
{
/* Check if it is a URI-escape sequence. */
if (CHECK(parser->buffer, '%')) {
if (!STRING_EXTEND(parser, string))
goto error;
if (!yaml_parser_scan_uri_escapes(parser,
directive, start_mark, &string)) goto error;
}
else {
if (!READ(parser, string)) goto error;
}
length ++;
if (!CACHE(parser, 1)) goto error;
}
/* Check if the tag is non-empty. */
if (!length) {
if (!STRING_EXTEND(parser, string))
goto error;
yaml_parser_set_scanner_error(parser, directive ?
"while parsing a %TAG directive" : "while parsing a tag",
start_mark, "did not find expected tag URI");
goto error;
}
*uri = string.start;
return 1;
error:
STRING_DEL(parser, string);
return 0;
}
/*
* Decode an URI-escape sequence corresponding to a single UTF-8 character.
*/
static int
yaml_parser_scan_uri_escapes(yaml_parser_t *parser, int directive,
yaml_mark_t start_mark, yaml_string_t *string)
{
int width = 0;
/* Decode the required number of characters. */
do {
unsigned char octet = 0;
/* Check for a URI-escaped octet. */
if (!CACHE(parser, 3)) return 0;
if (!(CHECK(parser->buffer, '%')
&& IS_HEX_AT(parser->buffer, 1)
&& IS_HEX_AT(parser->buffer, 2))) {
return yaml_parser_set_scanner_error(parser, directive ?
"while parsing a %TAG directive" : "while parsing a tag",
start_mark, "did not find URI escaped octet");
}
/* Get the octet. */
octet = (AS_HEX_AT(parser->buffer, 1) << 4) + AS_HEX_AT(parser->buffer, 2);
/* If it is the leading octet, determine the length of the UTF-8 sequence. */
if (!width)
{
width = (octet & 0x80) == 0x00 ? 1 :
(octet & 0xE0) == 0xC0 ? 2 :
(octet & 0xF0) == 0xE0 ? 3 :
(octet & 0xF8) == 0xF0 ? 4 : 0;
if (!width) {
return yaml_parser_set_scanner_error(parser, directive ?
"while parsing a %TAG directive" : "while parsing a tag",
start_mark, "found an incorrect leading UTF-8 octet");
}
}
else
{
/* Check if the trailing octet is correct. */
if ((octet & 0xC0) != 0x80) {
return yaml_parser_set_scanner_error(parser, directive ?
"while parsing a %TAG directive" : "while parsing a tag",
start_mark, "found an incorrect trailing UTF-8 octet");
}
}
/* Copy the octet and move the pointers. */
*(string->pointer++) = octet;
SKIP(parser);
SKIP(parser);
SKIP(parser);
} while (--width);
return 1;
}
/*
* Scan a block scalar.
*/
static int
yaml_parser_scan_block_scalar(yaml_parser_t *parser, yaml_token_t *token,
int literal)
{
yaml_mark_t start_mark;
yaml_mark_t end_mark;
yaml_string_t string = NULL_STRING;
yaml_string_t leading_break = NULL_STRING;
yaml_string_t trailing_breaks = NULL_STRING;
int chomping = 0;
int increment = 0;
int indent = 0;
int leading_blank = 0;
int trailing_blank = 0;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
/* Eat the indicator '|' or '>'. */
start_mark = parser->mark;
SKIP(parser);
/* Scan the additional block scalar indicators. */
if (!CACHE(parser, 1)) goto error;
/* Check for a chomping indicator. */
if (CHECK(parser->buffer, '+') || CHECK(parser->buffer, '-'))
{
/* Set the chomping method and eat the indicator. */
chomping = CHECK(parser->buffer, '+') ? +1 : -1;
SKIP(parser);
/* Check for an indentation indicator. */
if (!CACHE(parser, 1)) goto error;
if (IS_DIGIT(parser->buffer))
{
/* Check that the intendation is greater than 0. */
if (CHECK(parser->buffer, '0')) {
yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
start_mark, "found an intendation indicator equal to 0");
goto error;
}
/* Get the intendation level and eat the indicator. */
increment = AS_DIGIT(parser->buffer);
SKIP(parser);
}
}
/* Do the same as above, but in the opposite order. */
else if (IS_DIGIT(parser->buffer))
{
if (CHECK(parser->buffer, '0')) {
yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
start_mark, "found an intendation indicator equal to 0");
goto error;
}
increment = AS_DIGIT(parser->buffer);
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
if (CHECK(parser->buffer, '+') || CHECK(parser->buffer, '-')) {
chomping = CHECK(parser->buffer, '+') ? +1 : -1;
SKIP(parser);
}
}
/* Eat whitespaces and comments to the end of the line. */
if (!CACHE(parser, 1)) goto error;
while (IS_BLANK(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
if (CHECK(parser->buffer, '#')) {
while (!IS_BREAKZ(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) goto error;
}
}
/* Check if we are at the end of the line. */
if (!IS_BREAKZ(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
start_mark, "did not find expected comment or line break");
goto error;
}
/* Eat a line break. */
if (IS_BREAK(parser->buffer)) {
if (!CACHE(parser, 2)) goto error;
SKIP_LINE(parser);
}
end_mark = parser->mark;
/* Set the intendation level if it was specified. */
if (increment) {
indent = parser->indent >= 0 ? parser->indent+increment : increment;
}
/* Scan the leading line breaks and determine the indentation level if needed. */
if (!yaml_parser_scan_block_scalar_breaks(parser, &indent, &trailing_breaks,
start_mark, &end_mark)) goto error;
/* Scan the block scalar content. */
if (!CACHE(parser, 1)) goto error;
while ((int)parser->mark.column == indent && !IS_Z(parser->buffer))
{
/*
* We are at the beginning of a non-empty line.
*/
/* Is it a trailing whitespace? */
trailing_blank = IS_BLANK(parser->buffer);
/* Check if we need to fold the leading line break. */
if (!literal && (*leading_break.start == '\n')
&& !leading_blank && !trailing_blank)
{
/* Do we need to join the lines by space? */
if (*trailing_breaks.start == '\0') {
if (!STRING_EXTEND(parser, string)) goto error;
*(string.pointer ++) = ' ';
}
CLEAR(parser, leading_break);
}
else {
if (!JOIN(parser, string, leading_break)) goto error;
CLEAR(parser, leading_break);
}
/* Append the remaining line breaks. */
if (!JOIN(parser, string, trailing_breaks)) goto error;
CLEAR(parser, trailing_breaks);
/* Is it a leading whitespace? */
leading_blank = IS_BLANK(parser->buffer);
/* Consume the current line. */
while (!IS_BREAKZ(parser->buffer)) {
if (!READ(parser, string)) goto error;
if (!CACHE(parser, 1)) goto error;
}
/* Consume the line break. */
if (!CACHE(parser, 2)) goto error;
if (!READ_LINE(parser, leading_break)) goto error;
/* Eat the following intendation spaces and line breaks. */
if (!yaml_parser_scan_block_scalar_breaks(parser,
&indent, &trailing_breaks, start_mark, &end_mark)) goto error;
}
/* Chomp the tail. */
if (chomping != -1) {
if (!JOIN(parser, string, leading_break)) goto error;
}
if (chomping == 1) {
if (!JOIN(parser, string, trailing_breaks)) goto error;
}
/* Create a token. */
SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
literal ? YAML_LITERAL_SCALAR_STYLE : YAML_FOLDED_SCALAR_STYLE,
start_mark, end_mark);
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
return 1;
error:
STRING_DEL(parser, string);
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
return 0;
}
/*
* Scan intendation spaces and line breaks for a block scalar. Determine the
* intendation level if needed.
*/
static int
yaml_parser_scan_block_scalar_breaks(yaml_parser_t *parser,
int *indent, yaml_string_t *breaks,
yaml_mark_t start_mark, yaml_mark_t *end_mark)
{
int max_indent = 0;
*end_mark = parser->mark;
/* Eat the intendation spaces and line breaks. */
while (1)
{
/* Eat the intendation spaces. */
if (!CACHE(parser, 1)) return 0;
while ((!*indent || (int)parser->mark.column < *indent)
&& IS_SPACE(parser->buffer)) {
SKIP(parser);
if (!CACHE(parser, 1)) return 0;
}
if ((int)parser->mark.column > max_indent)
max_indent = (int)parser->mark.column;
/* Check for a tab character messing the intendation. */
if ((!*indent || (int)parser->mark.column < *indent)
&& IS_TAB(parser->buffer)) {
return yaml_parser_set_scanner_error(parser, "while scanning a block scalar",
start_mark, "found a tab character where an intendation space is expected");
}
/* Have we found a non-empty line? */
if (!IS_BREAK(parser->buffer)) break;
/* Consume the line break. */
if (!CACHE(parser, 2)) return 0;
if (!READ_LINE(parser, *breaks)) return 0;
*end_mark = parser->mark;
}
/* Determine the indentation level if needed. */
if (!*indent) {
*indent = max_indent;
if (*indent < parser->indent + 1)
*indent = parser->indent + 1;
if (*indent < 1)
*indent = 1;
}
return 1;
}
/*
* Scan a quoted scalar.
*/
static int
yaml_parser_scan_flow_scalar(yaml_parser_t *parser, yaml_token_t *token,
int single)
{
yaml_mark_t start_mark;
yaml_mark_t end_mark;
yaml_string_t string = NULL_STRING;
yaml_string_t leading_break = NULL_STRING;
yaml_string_t trailing_breaks = NULL_STRING;
yaml_string_t whitespaces = NULL_STRING;
int leading_blanks;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, whitespaces, INITIAL_STRING_SIZE)) goto error;
/* Eat the left quote. */
start_mark = parser->mark;
SKIP(parser);
/* Consume the content of the quoted scalar. */
while (1)
{
/* Check that there are no document indicators at the beginning of the line. */
if (!CACHE(parser, 4)) goto error;
if (parser->mark.column == 0 &&
((CHECK_AT(parser->buffer, '-', 0) &&
CHECK_AT(parser->buffer, '-', 1) &&
CHECK_AT(parser->buffer, '-', 2)) ||
(CHECK_AT(parser->buffer, '.', 0) &&
CHECK_AT(parser->buffer, '.', 1) &&
CHECK_AT(parser->buffer, '.', 2))) &&
IS_BLANKZ_AT(parser->buffer, 3))
{
yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
start_mark, "found unexpected document indicator");
goto error;
}
/* Check for EOF. */
if (IS_Z(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a quoted scalar",
start_mark, "found unexpected end of stream");
goto error;
}
/* Consume non-blank characters. */
if (!CACHE(parser, 2)) goto error;
leading_blanks = 0;
while (!IS_BLANKZ(parser->buffer))
{
/* Check for an escaped single quote. */
if (single && CHECK_AT(parser->buffer, '\'', 0)
&& CHECK_AT(parser->buffer, '\'', 1))
{
if (!STRING_EXTEND(parser, string)) goto error;
*(string.pointer++) = '\'';
SKIP(parser);
SKIP(parser);
}
/* Check for the right quote. */
else if (CHECK(parser->buffer, single ? '\'' : '"'))
{
break;
}
/* Check for an escaped line break. */
else if (!single && CHECK(parser->buffer, '\\')
&& IS_BREAK_AT(parser->buffer, 1))
{
if (!CACHE(parser, 3)) goto error;
SKIP(parser);
SKIP_LINE(parser);
leading_blanks = 1;
break;
}
/* Check for an escape sequence. */
else if (!single && CHECK(parser->buffer, '\\'))
{
size_t code_length = 0;
if (!STRING_EXTEND(parser, string)) goto error;
/* Check the escape character. */
switch (parser->buffer.pointer[1])
{
case '0':
*(string.pointer++) = '\0';
break;
case 'a':
*(string.pointer++) = '\x07';
break;
case 'b':
*(string.pointer++) = '\x08';
break;
case 't':
case '\t':
*(string.pointer++) = '\x09';
break;
case 'n':
*(string.pointer++) = '\x0A';
break;
case 'v':
*(string.pointer++) = '\x0B';
break;
case 'f':
*(string.pointer++) = '\x0C';
break;
case 'r':
*(string.pointer++) = '\x0D';
break;
case 'e':
*(string.pointer++) = '\x1B';
break;
case ' ':
*(string.pointer++) = '\x20';
break;
case '"':
*(string.pointer++) = '"';
break;
case '\'':
*(string.pointer++) = '\'';
break;
case '\\':
*(string.pointer++) = '\\';
break;
case 'N': /* NEL (#x85) */
*(string.pointer++) = '\xC2';
*(string.pointer++) = '\x85';
break;
case '_': /* #xA0 */
*(string.pointer++) = '\xC2';
*(string.pointer++) = '\xA0';
break;
case 'L': /* LS (#x2028) */
*(string.pointer++) = '\xE2';
*(string.pointer++) = '\x80';
*(string.pointer++) = '\xA8';
break;
case 'P': /* PS (#x2029) */
*(string.pointer++) = '\xE2';
*(string.pointer++) = '\x80';
*(string.pointer++) = '\xA9';
break;
case 'x':
code_length = 2;
break;
case 'u':
code_length = 4;
break;
case 'U':
code_length = 8;
break;
default:
yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
start_mark, "found unknown escape character");
goto error;
}
SKIP(parser);
SKIP(parser);
/* Consume an arbitrary escape code. */
if (code_length)
{
unsigned int value = 0;
size_t k;
/* Scan the character value. */
if (!CACHE(parser, code_length)) goto error;
for (k = 0; k < code_length; k ++) {
if (!IS_HEX_AT(parser->buffer, k)) {
yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
start_mark, "did not find expected hexdecimal number");
goto error;
}
value = (value << 4) + AS_HEX_AT(parser->buffer, k);
}
/* Check the value and write the character. */
if ((value >= 0xD800 && value <= 0xDFFF) || value > 0x10FFFF) {
yaml_parser_set_scanner_error(parser, "while parsing a quoted scalar",
start_mark, "found invalid Unicode character escape code");
goto error;
}
if (value <= 0x7F) {
*(string.pointer++) = value;
}
else if (value <= 0x7FF) {
*(string.pointer++) = 0xC0 + (value >> 6);
*(string.pointer++) = 0x80 + (value & 0x3F);
}
else if (value <= 0xFFFF) {
*(string.pointer++) = 0xE0 + (value >> 12);
*(string.pointer++) = 0x80 + ((value >> 6) & 0x3F);
*(string.pointer++) = 0x80 + (value & 0x3F);
}
else {
*(string.pointer++) = 0xF0 + (value >> 18);
*(string.pointer++) = 0x80 + ((value >> 12) & 0x3F);
*(string.pointer++) = 0x80 + ((value >> 6) & 0x3F);
*(string.pointer++) = 0x80 + (value & 0x3F);
}
/* Advance the pointer. */
for (k = 0; k < code_length; k ++) {
SKIP(parser);
}
}
}
else
{
/* It is a non-escaped non-blank character. */
if (!READ(parser, string)) goto error;
}
if (!CACHE(parser, 2)) goto error;
}
/* Check if we are at the end of the scalar. */
if (CHECK(parser->buffer, single ? '\'' : '"'))
break;
/* Consume blank characters. */
if (!CACHE(parser, 1)) goto error;
while (IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer))
{
if (IS_BLANK(parser->buffer))
{
/* Consume a space or a tab character. */
if (!leading_blanks) {
if (!READ(parser, whitespaces)) goto error;
}
else {
SKIP(parser);
}
}
else
{
if (!CACHE(parser, 2)) goto error;
/* Check if it is a first line break. */
if (!leading_blanks)
{
CLEAR(parser, whitespaces);
if (!READ_LINE(parser, leading_break)) goto error;
leading_blanks = 1;
}
else
{
if (!READ_LINE(parser, trailing_breaks)) goto error;
}
}
if (!CACHE(parser, 1)) goto error;
}
/* Join the whitespaces or fold line breaks. */
if (leading_blanks)
{
/* Do we need to fold line breaks? */
if (leading_break.start[0] == '\n') {
if (trailing_breaks.start[0] == '\0') {
if (!STRING_EXTEND(parser, string)) goto error;
*(string.pointer++) = ' ';
}
else {
if (!JOIN(parser, string, trailing_breaks)) goto error;
CLEAR(parser, trailing_breaks);
}
CLEAR(parser, leading_break);
}
else {
if (!JOIN(parser, string, leading_break)) goto error;
if (!JOIN(parser, string, trailing_breaks)) goto error;
CLEAR(parser, leading_break);
CLEAR(parser, trailing_breaks);
}
}
else
{
if (!JOIN(parser, string, whitespaces)) goto error;
CLEAR(parser, whitespaces);
}
}
/* Eat the right quote. */
SKIP(parser);
end_mark = parser->mark;
/* Create a token. */
SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
single ? YAML_SINGLE_QUOTED_SCALAR_STYLE : YAML_DOUBLE_QUOTED_SCALAR_STYLE,
start_mark, end_mark);
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
STRING_DEL(parser, whitespaces);
return 1;
error:
STRING_DEL(parser, string);
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
STRING_DEL(parser, whitespaces);
return 0;
}
/*
* Scan a plain scalar.
*/
static int
yaml_parser_scan_plain_scalar(yaml_parser_t *parser, yaml_token_t *token)
{
yaml_mark_t start_mark;
yaml_mark_t end_mark;
yaml_string_t string = NULL_STRING;
yaml_string_t leading_break = NULL_STRING;
yaml_string_t trailing_breaks = NULL_STRING;
yaml_string_t whitespaces = NULL_STRING;
int leading_blanks = 0;
int indent = parser->indent+1;
if (!STRING_INIT(parser, string, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, leading_break, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, trailing_breaks, INITIAL_STRING_SIZE)) goto error;
if (!STRING_INIT(parser, whitespaces, INITIAL_STRING_SIZE)) goto error;
start_mark = end_mark = parser->mark;
/* Consume the content of the plain scalar. */
while (1)
{
/* Check for a document indicator. */
if (!CACHE(parser, 4)) goto error;
if (parser->mark.column == 0 &&
((CHECK_AT(parser->buffer, '-', 0) &&
CHECK_AT(parser->buffer, '-', 1) &&
CHECK_AT(parser->buffer, '-', 2)) ||
(CHECK_AT(parser->buffer, '.', 0) &&
CHECK_AT(parser->buffer, '.', 1) &&
CHECK_AT(parser->buffer, '.', 2))) &&
IS_BLANKZ_AT(parser->buffer, 3)) break;
/* Check for a comment. */
if (CHECK(parser->buffer, '#'))
break;
/* Consume non-blank characters. */
while (!IS_BLANKZ(parser->buffer))
{
/* Check for 'x:x' in the flow context. TODO: Fix the test "spec-08-13". */
if (parser->flow_level
&& CHECK(parser->buffer, ':')
&& !IS_BLANKZ_AT(parser->buffer, 1)) {
yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
start_mark, "found unexpected ':'");
goto error;
}
/* Check for indicators that may end a plain scalar. */
if ((CHECK(parser->buffer, ':') && IS_BLANKZ_AT(parser->buffer, 1))
|| (parser->flow_level &&
(CHECK(parser->buffer, ',') || CHECK(parser->buffer, ':')
|| CHECK(parser->buffer, '?') || CHECK(parser->buffer, '[')
|| CHECK(parser->buffer, ']') || CHECK(parser->buffer, '{')
|| CHECK(parser->buffer, '}'))))
break;
/* Check if we need to join whitespaces and breaks. */
if (leading_blanks || whitespaces.start != whitespaces.pointer)
{
if (leading_blanks)
{
/* Do we need to fold line breaks? */
if (leading_break.start[0] == '\n') {
if (trailing_breaks.start[0] == '\0') {
if (!STRING_EXTEND(parser, string)) goto error;
*(string.pointer++) = ' ';
}
else {
if (!JOIN(parser, string, trailing_breaks)) goto error;
CLEAR(parser, trailing_breaks);
}
CLEAR(parser, leading_break);
}
else {
if (!JOIN(parser, string, leading_break)) goto error;
if (!JOIN(parser, string, trailing_breaks)) goto error;
CLEAR(parser, leading_break);
CLEAR(parser, trailing_breaks);
}
leading_blanks = 0;
}
else
{
if (!JOIN(parser, string, whitespaces)) goto error;
CLEAR(parser, whitespaces);
}
}
/* Copy the character. */
if (!READ(parser, string)) goto error;
end_mark = parser->mark;
if (!CACHE(parser, 2)) goto error;
}
/* Is it the end? */
if (!(IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer)))
break;
/* Consume blank characters. */
if (!CACHE(parser, 1)) goto error;
while (IS_BLANK(parser->buffer) || IS_BREAK(parser->buffer))
{
if (IS_BLANK(parser->buffer))
{
/* Check for tab character that abuse intendation. */
if (leading_blanks && (int)parser->mark.column < indent
&& IS_TAB(parser->buffer)) {
yaml_parser_set_scanner_error(parser, "while scanning a plain scalar",
start_mark, "found a tab character that violate intendation");
goto error;
}
/* Consume a space or a tab character. */
if (!leading_blanks) {
if (!READ(parser, whitespaces)) goto error;
}
else {
SKIP(parser);
}
}
else
{
if (!CACHE(parser, 2)) goto error;
/* Check if it is a first line break. */
if (!leading_blanks)
{
CLEAR(parser, whitespaces);
if (!READ_LINE(parser, leading_break)) goto error;
leading_blanks = 1;
}
else
{
if (!READ_LINE(parser, trailing_breaks)) goto error;
}
}
if (!CACHE(parser, 1)) goto error;
}
/* Check intendation level. */
if (!parser->flow_level && (int)parser->mark.column < indent)
break;
}
/* Create a token. */
SCALAR_TOKEN_INIT(*token, string.start, string.pointer-string.start,
YAML_PLAIN_SCALAR_STYLE, start_mark, end_mark);
/* Note that we change the 'simple_key_allowed' flag. */
if (leading_blanks) {
parser->simple_key_allowed = 1;
}
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
STRING_DEL(parser, whitespaces);
return 1;
error:
STRING_DEL(parser, string);
STRING_DEL(parser, leading_break);
STRING_DEL(parser, trailing_breaks);
STRING_DEL(parser, whitespaces);
return 0;
}
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