/* gmarkup.c - Simple XML-like parser
*
* Copyright 2000, 2003 Red Hat, Inc.
* Copyright 2007, 2008 Ryan Lortie <desrt@desrt.ca>
*
* GLib is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* GLib is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with GLib; see the file COPYING.LIB. If not,
* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include <stdarg.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include "gmarkup.h"
#include "galloca.h"
#include "gstrfuncs.h"
#include "gstring.h"
#include "gtestutils.h"
#include "glibintl.h"
/**
* SECTION:markup
* @Title: Simple XML Subset Parser
* @Short_description: parses a subset of XML
* @See_also: <ulink url="http://www.w3.org/TR/REC-xml/">XML
* Specification</ulink>
*
* The "GMarkup" parser is intended to parse a simple markup format
* that's a subset of XML. This is a small, efficient, easy-to-use
* parser. It should not be used if you expect to interoperate with
* other applications generating full-scale XML. However, it's very
* useful for application data files, config files, etc. where you
* know your application will be the only one writing the file.
* Full-scale XML parsers should be able to parse the subset used by
* GMarkup, so you can easily migrate to full-scale XML at a later
* time if the need arises.
*
* GMarkup is not guaranteed to signal an error on all invalid XML;
* the parser may accept documents that an XML parser would not.
* However, XML documents which are not well-formed<footnote
* id="wellformed">Being wellformed is a weaker condition than being
* valid. See the <ulink url="http://www.w3.org/TR/REC-xml/">XML
* specification</ulink> for definitions of these terms.</footnote>
* are not considered valid GMarkup documents.
*
* Simplifications to XML include:
* <itemizedlist>
* <listitem>Only UTF-8 encoding is allowed</listitem>
* <listitem>No user-defined entities</listitem>
* <listitem>Processing instructions, comments and the doctype declaration
* are "passed through" but are not interpreted in any way</listitem>
* <listitem>No DTD or validation.</listitem>
* </itemizedlist>
*
* The markup format does support:
* <itemizedlist>
* <listitem>Elements</listitem>
* <listitem>Attributes</listitem>
* <listitem>5 standard entities:
* <literal>&amp; &lt; &gt; &quot; &apos;</literal>
* </listitem>
* <listitem>Character references</listitem>
* <listitem>Sections marked as CDATA</listitem>
* </itemizedlist>
*/
GQuark
g_markup_error_quark (void)
{
return g_quark_from_static_string ("g-markup-error-quark");
}
typedef enum
{
STATE_START,
STATE_AFTER_OPEN_ANGLE,
STATE_AFTER_CLOSE_ANGLE,
STATE_AFTER_ELISION_SLASH, /* the slash that obviates need for end element */
STATE_INSIDE_OPEN_TAG_NAME,
STATE_INSIDE_ATTRIBUTE_NAME,
STATE_AFTER_ATTRIBUTE_NAME,
STATE_BETWEEN_ATTRIBUTES,
STATE_AFTER_ATTRIBUTE_EQUALS_SIGN,
STATE_INSIDE_ATTRIBUTE_VALUE_SQ,
STATE_INSIDE_ATTRIBUTE_VALUE_DQ,
STATE_INSIDE_TEXT,
STATE_AFTER_CLOSE_TAG_SLASH,
STATE_INSIDE_CLOSE_TAG_NAME,
STATE_AFTER_CLOSE_TAG_NAME,
STATE_INSIDE_PASSTHROUGH,
STATE_ERROR
} GMarkupParseState;
typedef struct
{
const char *prev_element;
const GMarkupParser *prev_parser;
gpointer prev_user_data;
} GMarkupRecursionTracker;
struct _GMarkupParseContext
{
const GMarkupParser *parser;
GMarkupParseFlags flags;
gint line_number;
gint char_number;
gpointer user_data;
GDestroyNotify dnotify;
/* A piece of character data or an element that
* hasn't "ended" yet so we haven't yet called
* the callback for it.
*/
GString *partial_chunk;
GSList *spare_chunks;
GMarkupParseState state;
GSList *tag_stack;
GSList *tag_stack_gstr;
GSList *spare_list_nodes;
GString **attr_names;
GString **attr_values;
gint cur_attr;
gint alloc_attrs;
const gchar *current_text;
gssize current_text_len;
const gchar *current_text_end;
/* used to save the start of the last interesting thingy */
const gchar *start;
const gchar *iter;
guint document_empty : 1;
guint parsing : 1;
guint awaiting_pop : 1;
gint balance;
/* subparser support */
GSList *subparser_stack; /* (GMarkupRecursionTracker *) */
const char *subparser_element;
gpointer held_user_data;
};
/*
* Helpers to reduce our allocation overhead, we have
* a well defined allocation lifecycle.
*/
static GSList *
get_list_node (GMarkupParseContext *context, gpointer data)
{
GSList *node;
if (context->spare_list_nodes != NULL)
{
node = context->spare_list_nodes;
context->spare_list_nodes = g_slist_remove_link (context->spare_list_nodes, node);
}
else
node = g_slist_alloc();
node->data = data;
return node;
}
static void
free_list_node (GMarkupParseContext *context, GSList *node)
{
node->data = NULL;
context->spare_list_nodes = g_slist_concat (node, context->spare_list_nodes);
}
static inline void
string_blank (GString *string)
{
string->str[0] = '\0';
string->len = 0;
}
/**
* g_markup_parse_context_new:
* @parser: a #GMarkupParser
* @flags: one or more #GMarkupParseFlags
* @user_data: user data to pass to #GMarkupParser functions
* @user_data_dnotify: user data destroy notifier called when
* the parse context is freed
*
* Creates a new parse context. A parse context is used to parse
* marked-up documents. You can feed any number of documents into
* a context, as long as no errors occur; once an error occurs,
* the parse context can't continue to parse text (you have to
* free it and create a new parse context).
*
* Return value: a new #GMarkupParseContext
**/
GMarkupParseContext *
g_markup_parse_context_new (const GMarkupParser *parser,
GMarkupParseFlags flags,
gpointer user_data,
GDestroyNotify user_data_dnotify)
{
GMarkupParseContext *context;
g_return_val_if_fail (parser != NULL, NULL);
context = g_new (GMarkupParseContext, 1);
context->parser = parser;
context->flags = flags;
context->user_data = user_data;
context->dnotify = user_data_dnotify;
context->line_number = 1;
context->char_number = 1;
context->partial_chunk = NULL;
context->spare_chunks = NULL;
context->spare_list_nodes = NULL;
context->state = STATE_START;
context->tag_stack = NULL;
context->tag_stack_gstr = NULL;
context->attr_names = NULL;
context->attr_values = NULL;
context->cur_attr = -1;
context->alloc_attrs = 0;
context->current_text = NULL;
context->current_text_len = -1;
context->current_text_end = NULL;
context->start = NULL;
context->iter = NULL;
context->document_empty = TRUE;
context->parsing = FALSE;
context->awaiting_pop = FALSE;
context->subparser_stack = NULL;
context->subparser_element = NULL;
/* this is only looked at if awaiting_pop = TRUE. initialise anyway. */
context->held_user_data = NULL;
context->balance = 0;
return context;
}
static void
string_full_free (gpointer ptr)
{
g_string_free (ptr, TRUE);
}
static void clear_attributes (GMarkupParseContext *context);
/**
* g_markup_parse_context_free:
* @context: a #GMarkupParseContext
*
* Frees a #GMarkupParseContext.
*
* This function can't be called from inside one of the
* #GMarkupParser functions or while a subparser is pushed.
*/
void
g_markup_parse_context_free (GMarkupParseContext *context)
{
g_return_if_fail (context != NULL);
g_return_if_fail (!context->parsing);
g_return_if_fail (!context->subparser_stack);
g_return_if_fail (!context->awaiting_pop);
if (context->dnotify)
(* context->dnotify) (context->user_data);
clear_attributes (context);
g_free (context->attr_names);
g_free (context->attr_values);
g_slist_free_full (context->tag_stack_gstr, string_full_free);
g_slist_free (context->tag_stack);
g_slist_free_full (context->spare_chunks, string_full_free);
g_slist_free (context->spare_list_nodes);
if (context->partial_chunk)
g_string_free (context->partial_chunk, TRUE);
g_free (context);
}
static void pop_subparser_stack (GMarkupParseContext *context);
static void
mark_error (GMarkupParseContext *context,
GError *error)
{
context->state = STATE_ERROR;
if (context->parser->error)
(*context->parser->error) (context, error, context->user_data);
/* report the error all the way up to free all the user-data */
while (context->subparser_stack)
{
pop_subparser_stack (context);
context->awaiting_pop = FALSE; /* already been freed */
if (context->parser->error)
(*context->parser->error) (context, error, context->user_data);
}
}
static void
set_error (GMarkupParseContext *context,
GError **error,
GMarkupError code,
const gchar *format,
...) G_GNUC_PRINTF (4, 5);
static void
set_error_literal (GMarkupParseContext *context,
GError **error,
GMarkupError code,
const gchar *message)
{
GError *tmp_error;
tmp_error = g_error_new_literal (G_MARKUP_ERROR, code, message);
g_prefix_error (&tmp_error,
_("Error on line %d char %d: "),
context->line_number,
context->char_number);
mark_error (context, tmp_error);
g_propagate_error (error, tmp_error);
}
static void
set_error (GMarkupParseContext *context,
GError **error,
GMarkupError code,
const gchar *format,
...)
{
gchar *s;
gchar *s_valid;
va_list args;
va_start (args, format);
s = g_strdup_vprintf (format, args);
va_end (args);
/* Make sure that the GError message is valid UTF-8
* even if it is complaining about invalid UTF-8 in the markup
*/
s_valid = _g_utf8_make_valid (s);
set_error_literal (context, error, code, s);
g_free (s);
g_free (s_valid);
}
static void
propagate_error (GMarkupParseContext *context,
GError **dest,
GError *src)
{
if (context->flags & G_MARKUP_PREFIX_ERROR_POSITION)
g_prefix_error (&src,
_("Error on line %d char %d: "),
context->line_number,
context->char_number);
mark_error (context, src);
g_propagate_error (dest, src);
}
#define IS_COMMON_NAME_END_CHAR(c) \
((c) == '=' || (c) == '/' || (c) == '>' || (c) == ' ')
static gboolean
slow_name_validate (GMarkupParseContext *context,
const gchar *name,
GError **error)
{
const gchar *p = name;
if (!g_utf8_validate (name, strlen (name), NULL))
{
set_error (context, error, G_MARKUP_ERROR_BAD_UTF8,
_("Invalid UTF-8 encoded text in name - not valid '%s'"), name);
return FALSE;
}
if (!(g_ascii_isalpha (*p) ||
(!IS_COMMON_NAME_END_CHAR (*p) &&
(*p == '_' ||
*p == ':' ||
g_unichar_isalpha (g_utf8_get_char (p))))))
{
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("'%s' is not a valid name "), name);
return FALSE;
}
for (p = g_utf8_next_char (name); *p != '\0'; p = g_utf8_next_char (p))
{
/* is_name_char */
if (!(g_ascii_isalnum (*p) ||
(!IS_COMMON_NAME_END_CHAR (*p) &&
(*p == '.' ||
*p == '-' ||
*p == '_' ||
*p == ':' ||
g_unichar_isalpha (g_utf8_get_char (p))))))
{
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("'%s' is not a valid name: '%c' "), name, *p);
return FALSE;
}
}
return TRUE;
}
/*
* Use me for elements, attributes etc.
*/
static gboolean
name_validate (GMarkupParseContext *context,
const gchar *name,
GError **error)
{
char mask;
const char *p;
/* name start char */
p = name;
if (G_UNLIKELY (IS_COMMON_NAME_END_CHAR (*p) ||
!(g_ascii_isalpha (*p) || *p == '_' || *p == ':')))
goto slow_validate;
for (mask = *p++; *p != '\0'; p++)
{
mask |= *p;
/* is_name_char */
if (G_UNLIKELY (!(g_ascii_isalnum (*p) ||
(!IS_COMMON_NAME_END_CHAR (*p) &&
(*p == '.' ||
*p == '-' ||
*p == '_' ||
*p == ':')))))
goto slow_validate;
}
if (mask & 0x80) /* un-common / non-ascii */
goto slow_validate;
return TRUE;
slow_validate:
return slow_name_validate (context, name, error);
}
static gboolean
text_validate (GMarkupParseContext *context,
const gchar *p,
gint len,
GError **error)
{
if (!g_utf8_validate (p, len, NULL))
{
set_error (context, error, G_MARKUP_ERROR_BAD_UTF8,
_("Invalid UTF-8 encoded text in name - not valid '%s'"), p);
return FALSE;
}
else
return TRUE;
}
static gchar*
char_str (gunichar c,
gchar *buf)
{
memset (buf, 0, 8);
g_unichar_to_utf8 (c, buf);
return buf;
}
static gchar*
utf8_str (const gchar *utf8,
gchar *buf)
{
char_str (g_utf8_get_char (utf8), buf);
return buf;
}
static void
set_unescape_error (GMarkupParseContext *context,
GError **error,
const gchar *remaining_text,
GMarkupError code,
const gchar *format,
...)
{
GError *tmp_error;
gchar *s;
va_list args;
gint remaining_newlines;
const gchar *p;
remaining_newlines = 0;
p = remaining_text;
while (*p != '\0')
{
if (*p == '\n')
++remaining_newlines;
++p;
}
va_start (args, format);
s = g_strdup_vprintf (format, args);
va_end (args);
tmp_error = g_error_new (G_MARKUP_ERROR,
code,
_("Error on line %d: %s"),
context->line_number - remaining_newlines,
s);
g_free (s);
mark_error (context, tmp_error);
g_propagate_error (error, tmp_error);
}
/*
* re-write the GString in-place, unescaping anything that escaped.
* most XML does not contain entities, or escaping.
*/
static gboolean
unescape_gstring_inplace (GMarkupParseContext *context,
GString *string,
gboolean *is_ascii,
GError **error)
{
char mask, *to;
int line_num = 1;
const char *from;
gboolean normalize_attribute;
*is_ascii = FALSE;
/* are we unescaping an attribute or not ? */
if (context->state == STATE_INSIDE_ATTRIBUTE_VALUE_SQ ||
context->state == STATE_INSIDE_ATTRIBUTE_VALUE_DQ)
normalize_attribute = TRUE;
else
normalize_attribute = FALSE;
/*
* Meeks' theorum: unescaping can only shrink text.
* for < etc. this is obvious, for  more
* thought is required, but this is patently so.
*/
mask = 0;
for (from = to = string->str; *from != '\0'; from++, to++)
{
*to = *from;
mask |= *to;
if (*to == '\n')
line_num++;
if (normalize_attribute && (*to == '\t' || *to == '\n'))
*to = ' ';
if (*to == '\r')
{
*to = normalize_attribute ? ' ' : '\n';
if (from[1] == '\n')
from++;
}
if (*from == '&')
{
from++;
if (*from == '#')
{
gboolean is_hex = FALSE;
gulong l;
gchar *end = NULL;
from++;
if (*from == 'x')
{
is_hex = TRUE;
from++;
}
/* digit is between start and p */
errno = 0;
if (is_hex)
l = strtoul (from, &end, 16);
else
l = strtoul (from, &end, 10);
if (end == from || errno != 0)
{
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Failed to parse '%-.*s', which "
"should have been a digit "
"inside a character reference "
"(ê for example) - perhaps "
"the digit is too large"),
end - from, from);
return FALSE;
}
else if (*end != ';')
{
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Character reference did not end with a "
"semicolon; "
"most likely you used an ampersand "
"character without intending to start "
"an entity - escape ampersand as &"));
return FALSE;
}
else
{
/* characters XML 1.1 permits */
if ((0 < l && l <= 0xD7FF) ||
(0xE000 <= l && l <= 0xFFFD) ||
(0x10000 <= l && l <= 0x10FFFF))
{
gchar buf[8];
char_str (l, buf);
strcpy (to, buf);
to += strlen (buf) - 1;
from = end;
if (l >= 0x80) /* not ascii */
mask |= 0x80;
}
else
{
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Character reference '%-.*s' does not "
"encode a permitted character"),
end - from, from);
return FALSE;
}
}
}
else if (strncmp (from, "lt;", 3) == 0)
{
*to = '<';
from += 2;
}
else if (strncmp (from, "gt;", 3) == 0)
{
*to = '>';
from += 2;
}
else if (strncmp (from, "amp;", 4) == 0)
{
*to = '&';
from += 3;
}
else if (strncmp (from, "quot;", 5) == 0)
{
*to = '"';
from += 4;
}
else if (strncmp (from, "apos;", 5) == 0)
{
*to = '\'';
from += 4;
}
else
{
if (*from == ';')
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Empty entity '&;' seen; valid "
"entities are: & " < > '"));
else
{
const char *end = strchr (from, ';');
if (end)
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Entity name '%-.*s' is not known"),
end-from, from);
else
set_unescape_error (context, error,
from, G_MARKUP_ERROR_PARSE,
_("Entity did not end with a semicolon; "
"most likely you used an ampersand "
"character without intending to start "
"an entity - escape ampersand as &"));
}
return FALSE;
}
}
}
g_assert (to - string->str <= string->len);
if (to - string->str != string->len)
g_string_truncate (string, to - string->str);
*is_ascii = !(mask & 0x80);
return TRUE;
}
static inline gboolean
advance_char (GMarkupParseContext *context)
{
context->iter++;
context->char_number++;
if (G_UNLIKELY (context->iter == context->current_text_end))
return FALSE;
else if (G_UNLIKELY (*context->iter == '\n'))
{
context->line_number++;
context->char_number = 1;
}
return TRUE;
}
static inline gboolean
xml_isspace (char c)
{
return c == ' ' || c == '\t' || c == '\n' || c == '\r';
}
static void
skip_spaces (GMarkupParseContext *context)
{
do
{
if (!xml_isspace (*context->iter))
return;
}
while (advance_char (context));
}
static void
advance_to_name_end (GMarkupParseContext *context)
{
do
{
if (IS_COMMON_NAME_END_CHAR (*(context->iter)))
return;
if (xml_isspace (*(context->iter)))
return;
}
while (advance_char (context));
}
static void
release_chunk (GMarkupParseContext *context, GString *str)
{
GSList *node;
if (!str)
return;
if (str->allocated_len > 256)
{ /* large strings are unusual and worth freeing */
g_string_free (str, TRUE);
return;
}
string_blank (str);
node = get_list_node (context, str);
context->spare_chunks = g_slist_concat (node, context->spare_chunks);
}
static void
add_to_partial (GMarkupParseContext *context,
const gchar *text_start,
const gchar *text_end)
{
if (context->partial_chunk == NULL)
{ /* allocate a new chunk to parse into */
if (context->spare_chunks != NULL)
{
GSList *node = context->spare_chunks;
context->spare_chunks = g_slist_remove_link (context->spare_chunks, node);
context->partial_chunk = node->data;
free_list_node (context, node);
}
else
context->partial_chunk = g_string_sized_new (MAX (28, text_end - text_start));
}
if (text_start != text_end)
g_string_insert_len (context->partial_chunk, -1,
text_start, text_end - text_start);
}
static inline void
truncate_partial (GMarkupParseContext *context)
{
if (context->partial_chunk != NULL)
string_blank (context->partial_chunk);
}
static inline const gchar*
current_element (GMarkupParseContext *context)
{
return context->tag_stack->data;
}
static void
pop_subparser_stack (GMarkupParseContext *context)
{
GMarkupRecursionTracker *tracker;
g_assert (context->subparser_stack);
tracker = context->subparser_stack->data;
context->awaiting_pop = TRUE;
context->held_user_data = context->user_data;
context->user_data = tracker->prev_user_data;
context->parser = tracker->prev_parser;
context->subparser_element = tracker->prev_element;
g_slice_free (GMarkupRecursionTracker, tracker);
context->subparser_stack = g_slist_delete_link (context->subparser_stack,
context->subparser_stack);
}
static void
push_partial_as_tag (GMarkupParseContext *context)
{
GString *str = context->partial_chunk;
/* sadly, this is exported by gmarkup_get_element_stack as-is */
context->tag_stack = g_slist_concat (get_list_node (context, str->str), context->tag_stack);
context->tag_stack_gstr = g_slist_concat (get_list_node (context, str), context->tag_stack_gstr);
context->partial_chunk = NULL;
}
static void
pop_tag (GMarkupParseContext *context)
{
GSList *nodea, *nodeb;
nodea = context->tag_stack;
nodeb = context->tag_stack_gstr;
release_chunk (context, nodeb->data);
context->tag_stack = g_slist_remove_link (context->tag_stack, nodea);
context->tag_stack_gstr = g_slist_remove_link (context->tag_stack_gstr, nodeb);
free_list_node (context, nodea);
free_list_node (context, nodeb);
}
static void
possibly_finish_subparser (GMarkupParseContext *context)
{
if (current_element (context) == context->subparser_element)
pop_subparser_stack (context);
}
static void
ensure_no_outstanding_subparser (GMarkupParseContext *context)
{
if (context->awaiting_pop)
g_critical ("During the first end_element call after invoking a "
"subparser you must pop the subparser stack and handle "
"the freeing of the subparser user_data. This can be "
"done by calling the end function of the subparser. "
"Very probably, your program just leaked memory.");
/* let valgrind watch the pointer disappear... */
context->held_user_data = NULL;
context->awaiting_pop = FALSE;
}
static const gchar*
current_attribute (GMarkupParseContext *context)
{
g_assert (context->cur_attr >= 0);
return context->attr_names[context->cur_attr]->str;
}
static void
add_attribute (GMarkupParseContext *context, GString *str)
{
if (context->cur_attr + 2 >= context->alloc_attrs)
{
context->alloc_attrs += 5; /* silly magic number */
context->attr_names = g_realloc (context->attr_names, sizeof(GString*)*context->alloc_attrs);
context->attr_values = g_realloc (context->attr_values, sizeof(GString*)*context->alloc_attrs);
}
context->cur_attr++;
context->attr_names[context->cur_attr] = str;
context->attr_values[context->cur_attr] = NULL;
context->attr_names[context->cur_attr+1] = NULL;
context->attr_values[context->cur_attr+1] = NULL;
}
static void
clear_attributes (GMarkupParseContext *context)
{
/* Go ahead and free the attributes. */
for (; context->cur_attr >= 0; context->cur_attr--)
{
int pos = context->cur_attr;
release_chunk (context, context->attr_names[pos]);
release_chunk (context, context->attr_values[pos]);
context->attr_names[pos] = context->attr_values[pos] = NULL;
}
g_assert (context->cur_attr == -1);
g_assert (context->attr_names == NULL ||
context->attr_names[0] == NULL);
g_assert (context->attr_values == NULL ||
context->attr_values[0] == NULL);
}
/* This has to be a separate function to ensure the alloca's
* are unwound on exit - otherwise we grow & blow the stack
* with large documents
*/
static inline void
emit_start_element (GMarkupParseContext *context,
GError **error)
{
int i;
const gchar *start_name;
const gchar **attr_names;
const gchar **attr_values;
GError *tmp_error;
attr_names = g_newa (const gchar *, context->cur_attr + 2);
attr_values = g_newa (const gchar *, context->cur_attr + 2);
for (i = 0; i < context->cur_attr + 1; i++)
{
attr_names[i] = context->attr_names[i]->str;
attr_values[i] = context->attr_values[i]->str;
}
attr_names[i] = NULL;
attr_values[i] = NULL;
/* Call user callback for element start */
tmp_error = NULL;
start_name = current_element (context);
if (context->parser->start_element &&
name_validate (context, start_name, error))
(* context->parser->start_element) (context,
start_name,
(const gchar **)attr_names,
(const gchar **)attr_values,
context->user_data,
&tmp_error);
clear_attributes (context);
if (tmp_error != NULL)
propagate_error (context, error, tmp_error);
}
/**
* g_markup_parse_context_parse:
* @context: a #GMarkupParseContext
* @text: chunk of text to parse
* @text_len: length of @text in bytes
* @error: return location for a #GError
*
* Feed some data to the #GMarkupParseContext.
*
* The data need not be valid UTF-8; an error will be signaled if
* it's invalid. The data need not be an entire document; you can
* feed a document into the parser incrementally, via multiple calls
* to this function. Typically, as you receive data from a network
* connection or file, you feed each received chunk of data into this
* function, aborting the process if an error occurs. Once an error
* is reported, no further data may be fed to the #GMarkupParseContext;
* all errors are fatal.
*
* Return value: %FALSE if an error occurred, %TRUE on success
*/
gboolean
g_markup_parse_context_parse (GMarkupParseContext *context,
const gchar *text,
gssize text_len,
GError **error)
{
g_return_val_if_fail (context != NULL, FALSE);
g_return_val_if_fail (text != NULL, FALSE);
g_return_val_if_fail (context->state != STATE_ERROR, FALSE);
g_return_val_if_fail (!context->parsing, FALSE);
if (text_len < 0)
text_len = strlen (text);
if (text_len == 0)
return TRUE;
context->parsing = TRUE;
context->current_text = text;
context->current_text_len = text_len;
context->current_text_end = context->current_text + text_len;
context->iter = context->current_text;
context->start = context->iter;
if (context->current_text_len == 0)
goto finished;
while (context->iter != context->current_text_end)
{
switch (context->state)
{
case STATE_START:
/* Possible next state: AFTER_OPEN_ANGLE */
g_assert (context->tag_stack == NULL);
/* whitespace is ignored outside of any elements */
skip_spaces (context);
if (context->iter != context->current_text_end)
{
if (*context->iter == '<')
{
/* Move after the open angle */
advance_char (context);
context->state = STATE_AFTER_OPEN_ANGLE;
/* this could start a passthrough */
context->start = context->iter;
/* document is now non-empty */
context->document_empty = FALSE;
}
else
{
set_error_literal (context,
error,
G_MARKUP_ERROR_PARSE,
_("Document must begin with an element (e.g. <book>)"));
}
}
break;
case STATE_AFTER_OPEN_ANGLE:
/* Possible next states: INSIDE_OPEN_TAG_NAME,
* AFTER_CLOSE_TAG_SLASH, INSIDE_PASSTHROUGH
*/
if (*context->iter == '?' ||
*context->iter == '!')
{
/* include < in the passthrough */
const gchar *openangle = "<";
add_to_partial (context, openangle, openangle + 1);
context->start = context->iter;
context->balance = 1;
context->state = STATE_INSIDE_PASSTHROUGH;
}
else if (*context->iter == '/')
{
/* move after it */
advance_char (context);
context->state = STATE_AFTER_CLOSE_TAG_SLASH;
}
else if (!IS_COMMON_NAME_END_CHAR (*(context->iter)))
{
context->state = STATE_INSIDE_OPEN_TAG_NAME;
/* start of tag name */
context->start = context->iter;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("'%s' is not a valid character following "
"a '<' character; it may not begin an "
"element name"),
utf8_str (context->iter, buf));
}
break;
/* The AFTER_CLOSE_ANGLE state is actually sort of
* broken, because it doesn't correspond to a range
* of characters in the input stream as the others do,
* and thus makes things harder to conceptualize
*/
case STATE_AFTER_CLOSE_ANGLE:
/* Possible next states: INSIDE_TEXT, STATE_START */
if (context->tag_stack == NULL)
{
context->start = NULL;
context->state = STATE_START;
}
else
{
context->start = context->iter;
context->state = STATE_INSIDE_TEXT;
}
break;
case STATE_AFTER_ELISION_SLASH:
/* Possible next state: AFTER_CLOSE_ANGLE */
{
/* We need to pop the tag stack and call the end_element
* function, since this is the close tag
*/
GError *tmp_error = NULL;
g_assert (context->tag_stack != NULL);
possibly_finish_subparser (context);
tmp_error = NULL;
if (context->parser->end_element)
(* context->parser->end_element) (context,
current_element (context),
context->user_data,
&tmp_error);
ensure_no_outstanding_subparser (context);
if (tmp_error)
{
mark_error (context, tmp_error);
g_propagate_error (error, tmp_error);
}
else
{
if (*context->iter == '>')
{
/* move after the close angle */
advance_char (context);
context->state = STATE_AFTER_CLOSE_ANGLE;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Odd character '%s', expected a '>' character "
"to end the empty-element tag '%s'"),
utf8_str (context->iter, buf),
current_element (context));
}
}
pop_tag (context);
}
break;
case STATE_INSIDE_OPEN_TAG_NAME:
/* Possible next states: BETWEEN_ATTRIBUTES */
/* if there's a partial chunk then it's the first part of the
* tag name. If there's a context->start then it's the start
* of the tag name in current_text, the partial chunk goes
* before that start though.
*/
advance_to_name_end (context);
if (context->iter == context->current_text_end)
{
/* The name hasn't necessarily ended. Merge with
* partial chunk, leave state unchanged.
*/
add_to_partial (context, context->start, context->iter);
}
else
{
/* The name has ended. Combine it with the partial chunk
* if any; push it on the stack; enter next state.
*/
add_to_partial (context, context->start, context->iter);
push_partial_as_tag (context);
context->state = STATE_BETWEEN_ATTRIBUTES;
context->start = NULL;
}
break;
case STATE_INSIDE_ATTRIBUTE_NAME:
/* Possible next states: AFTER_ATTRIBUTE_NAME */
advance_to_name_end (context);
add_to_partial (context, context->start, context->iter);
/* read the full name, if we enter the equals sign state
* then add the attribute to the list (without the value),
* otherwise store a partial chunk to be prepended later.
*/
if (context->iter != context->current_text_end)
context->state = STATE_AFTER_ATTRIBUTE_NAME;
break;
case STATE_AFTER_ATTRIBUTE_NAME:
/* Possible next states: AFTER_ATTRIBUTE_EQUALS_SIGN */
skip_spaces (context);
if (context->iter != context->current_text_end)
{
/* The name has ended. Combine it with the partial chunk
* if any; push it on the stack; enter next state.
*/
if (!name_validate (context, context->partial_chunk->str, error))
break;
add_attribute (context, context->partial_chunk);
context->partial_chunk = NULL;
context->start = NULL;
if (*context->iter == '=')
{
advance_char (context);
context->state = STATE_AFTER_ATTRIBUTE_EQUALS_SIGN;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Odd character '%s', expected a '=' after "
"attribute name '%s' of element '%s'"),
utf8_str (context->iter, buf),
current_attribute (context),
current_element (context));
}
}
break;
case STATE_BETWEEN_ATTRIBUTES:
/* Possible next states: AFTER_CLOSE_ANGLE,
* AFTER_ELISION_SLASH, INSIDE_ATTRIBUTE_NAME
*/
skip_spaces (context);
if (context->iter != context->current_text_end)
{
if (*context->iter == '/')
{
advance_char (context);
context->state = STATE_AFTER_ELISION_SLASH;
}
else if (*context->iter == '>')
{
advance_char (context);
context->state = STATE_AFTER_CLOSE_ANGLE;
}
else if (!IS_COMMON_NAME_END_CHAR (*(context->iter)))
{
context->state = STATE_INSIDE_ATTRIBUTE_NAME;
/* start of attribute name */
context->start = context->iter;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Odd character '%s', expected a '>' or '/' "
"character to end the start tag of "
"element '%s', or optionally an attribute; "
"perhaps you used an invalid character in "
"an attribute name"),
utf8_str (context->iter, buf),
current_element (context));
}
/* If we're done with attributes, invoke
* the start_element callback
*/
if (context->state == STATE_AFTER_ELISION_SLASH ||
context->state == STATE_AFTER_CLOSE_ANGLE)
emit_start_element (context, error);
}
break;
case STATE_AFTER_ATTRIBUTE_EQUALS_SIGN:
/* Possible next state: INSIDE_ATTRIBUTE_VALUE_[SQ/DQ] */
skip_spaces (context);
if (context->iter != context->current_text_end)
{
if (*context->iter == '"')
{
advance_char (context);
context->state = STATE_INSIDE_ATTRIBUTE_VALUE_DQ;
context->start = context->iter;
}
else if (*context->iter == '\'')
{
advance_char (context);
context->state = STATE_INSIDE_ATTRIBUTE_VALUE_SQ;
context->start = context->iter;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Odd character '%s', expected an open quote mark "
"after the equals sign when giving value for "
"attribute '%s' of element '%s'"),
utf8_str (context->iter, buf),
current_attribute (context),
current_element (context));
}
}
break;
case STATE_INSIDE_ATTRIBUTE_VALUE_SQ:
case STATE_INSIDE_ATTRIBUTE_VALUE_DQ:
/* Possible next states: BETWEEN_ATTRIBUTES */
{
gchar delim;
if (context->state == STATE_INSIDE_ATTRIBUTE_VALUE_SQ)
{
delim = '\'';
}
else
{
delim = '"';
}
do
{
if (*context->iter == delim)
break;
}
while (advance_char (context));
}
if (context->iter == context->current_text_end)
{
/* The value hasn't necessarily ended. Merge with
* partial chunk, leave state unchanged.
*/
add_to_partial (context, context->start, context->iter);
}
else
{
gboolean is_ascii;
/* The value has ended at the quote mark. Combine it
* with the partial chunk if any; set it for the current
* attribute.
*/
add_to_partial (context, context->start, context->iter);
g_assert (context->cur_attr >= 0);
if (unescape_gstring_inplace (context, context->partial_chunk, &is_ascii, error) &&
(is_ascii || text_validate (context, context->partial_chunk->str,
context->partial_chunk->len, error)))
{
/* success, advance past quote and set state. */
context->attr_values[context->cur_attr] = context->partial_chunk;
context->partial_chunk = NULL;
advance_char (context);
context->state = STATE_BETWEEN_ATTRIBUTES;
context->start = NULL;
}
truncate_partial (context);
}
break;
case STATE_INSIDE_TEXT:
/* Possible next states: AFTER_OPEN_ANGLE */
do
{
if (*context->iter == '<')
break;
}
while (advance_char (context));
/* The text hasn't necessarily ended. Merge with
* partial chunk, leave state unchanged.
*/
add_to_partial (context, context->start, context->iter);
if (context->iter != context->current_text_end)
{
gboolean is_ascii;
/* The text has ended at the open angle. Call the text
* callback.
*/
if (unescape_gstring_inplace (context, context->partial_chunk, &is_ascii, error) &&
(is_ascii || text_validate (context, context->partial_chunk->str,
context->partial_chunk->len, error)))
{
GError *tmp_error = NULL;
if (context->parser->text)
(*context->parser->text) (context,
context->partial_chunk->str,
context->partial_chunk->len,
context->user_data,
&tmp_error);
if (tmp_error == NULL)
{
/* advance past open angle and set state. */
advance_char (context);
context->state = STATE_AFTER_OPEN_ANGLE;
/* could begin a passthrough */
context->start = context->iter;
}
else
propagate_error (context, error, tmp_error);
}
truncate_partial (context);
}
break;
case STATE_AFTER_CLOSE_TAG_SLASH:
/* Possible next state: INSIDE_CLOSE_TAG_NAME */
if (!IS_COMMON_NAME_END_CHAR (*(context->iter)))
{
context->state = STATE_INSIDE_CLOSE_TAG_NAME;
/* start of tag name */
context->start = context->iter;
}
else
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("'%s' is not a valid character following "
"the characters '</'; '%s' may not begin an "
"element name"),
utf8_str (context->iter, buf),
utf8_str (context->iter, buf));
}
break;
case STATE_INSIDE_CLOSE_TAG_NAME:
/* Possible next state: AFTER_CLOSE_TAG_NAME */
advance_to_name_end (context);
add_to_partial (context, context->start, context->iter);
if (context->iter != context->current_text_end)
context->state = STATE_AFTER_CLOSE_TAG_NAME;
break;
case STATE_AFTER_CLOSE_TAG_NAME:
/* Possible next state: AFTER_CLOSE_TAG_SLASH */
skip_spaces (context);
if (context->iter != context->current_text_end)
{
GString *close_name;
close_name = context->partial_chunk;
context->partial_chunk = NULL;
if (*context->iter != '>')
{
gchar buf[8];
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("'%s' is not a valid character following "
"the close element name '%s'; the allowed "
"character is '>'"),
utf8_str (context->iter, buf),
close_name->str);
}
else if (context->tag_stack == NULL)
{
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Element '%s' was closed, no element "
"is currently open"),
close_name->str);
}
else if (strcmp (close_name->str, current_element (context)) != 0)
{
set_error (context,
error,
G_MARKUP_ERROR_PARSE,
_("Element '%s' was closed, but the currently "
"open element is '%s'"),
close_name->str,
current_element (context));
}
else
{
GError *tmp_error;
advance_char (context);
context->state = STATE_AFTER_CLOSE_ANGLE;
context->start = NULL;
possibly_finish_subparser (context);
/* call the end_element callback */
tmp_error = NULL;
if (context->parser->end_element)
(* context->parser->end_element) (context,
close_name->str,
context->user_data,
&tmp_error);
ensure_no_outstanding_subparser (context);
pop_tag (context);
if (tmp_error)
propagate_error (context, error, tmp_error);
}
context->partial_chunk = close_name;
truncate_partial (context);
}
break;
case STATE_INSIDE_PASSTHROUGH:
/* Possible next state: AFTER_CLOSE_ANGLE */
do
{
if (*context->iter == '<')
context->balance++;
if (*context->iter == '>')
{
gchar *str;
gsize len;
context->balance--;
add_to_partial (context, context->start, context->iter);
context->start = context->iter;
str = context->partial_chunk->str;
len = context->partial_chunk->len;
if (str[1] == '?' && str[len - 1] == '?')
break;
if (strncmp (str, "<!--", 4) == 0 &&
strcmp (str + len - 2, "--") == 0)
break;
if (strncmp (str, "<![CDATA[", 9) == 0 &&
strcmp (str + len - 2, "]]") == 0)
break;
if (strncmp (str, "<!DOCTYPE", 9) == 0 &&
context->balance == 0)
break;
}
}
while (advance_char (context));
if (context->iter == context->current_text_end)
{
/* The passthrough hasn't necessarily ended. Merge with
* partial chunk, leave state unchanged.
*/
add_to_partial (context, context->start, context->iter);
}
else
{
/* The passthrough has ended at the close angle. Combine
* it with the partial chunk if any. Call the passthrough
* callback. Note that the open/close angles are
* included in the text of the passthrough.
*/
GError *tmp_error = NULL;
advance_char (context); /* advance past close angle */
add_to_partial (context, context->start, context->iter);
if (context->flags & G_MARKUP_TREAT_CDATA_AS_TEXT &&
strncmp (context->partial_chunk->str, "<![CDATA[", 9) == 0)
{
if (context->parser->text &&
text_validate (context,
context->partial_chunk->str + 9,
context->partial_chunk->len - 12,
error))
(*context->parser->text) (context,
context->partial_chunk->str + 9,
context->partial_chunk->len - 12,
context->user_data,
&tmp_error);
}
else if (context->parser->passthrough &&
text_validate (context,
context->partial_chunk->str,
context->partial_chunk->len,
error))
(*context->parser->passthrough) (context,
context->partial_chunk->str,
context->partial_chunk->len,
context->user_data,
&tmp_error);
truncate_partial (context);
if (tmp_error == NULL)
{
context->state = STATE_AFTER_CLOSE_ANGLE;
context->start = context->iter; /* could begin text */
}
else
propagate_error (context, error, tmp_error);
}
break;
case STATE_ERROR:
goto finished;
break;
default:
g_assert_not_reached ();
break;
}
}
finished:
context->parsing = FALSE;
return context->state != STATE_ERROR;
}
/**
* g_markup_parse_context_end_parse:
* @context: a #GMarkupParseContext
* @error: return location for a #GError
*
* Signals to the #GMarkupParseContext that all data has been
* fed into the parse context with g_markup_parse_context_parse().
*
* This function reports an error if the document isn't complete,
* for example if elements are still open.
*
* Return value: %TRUE on success, %FALSE if an error was set
*/
gboolean
g_markup_parse_context_end_parse (GMarkupParseContext *context,
GError **error)
{
g_return_val_if_fail (context != NULL, FALSE);
g_return_val_if_fail (!context->parsing, FALSE);
g_return_val_if_fail (context->state != STATE_ERROR, FALSE);
if (context->partial_chunk != NULL)
{
g_string_free (context->partial_chunk, TRUE);
context->partial_chunk = NULL;
}
if (context->document_empty)
{
set_error_literal (context, error, G_MARKUP_ERROR_EMPTY,
_("Document was empty or contained only whitespace"));
return FALSE;
}
context->parsing = TRUE;
switch (context->state)
{
case STATE_START:
/* Nothing to do */
break;
case STATE_AFTER_OPEN_ANGLE:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly just after an open angle bracket '<'"));
break;
case STATE_AFTER_CLOSE_ANGLE:
if (context->tag_stack != NULL)
{
/* Error message the same as for INSIDE_TEXT */
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly with elements still open - "
"'%s' was the last element opened"),
current_element (context));
}
break;
case STATE_AFTER_ELISION_SLASH:
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly, expected to see a close angle "
"bracket ending the tag <%s/>"), current_element (context));
break;
case STATE_INSIDE_OPEN_TAG_NAME:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly inside an element name"));
break;
case STATE_INSIDE_ATTRIBUTE_NAME:
case STATE_AFTER_ATTRIBUTE_NAME:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly inside an attribute name"));
break;
case STATE_BETWEEN_ATTRIBUTES:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly inside an element-opening "
"tag."));
break;
case STATE_AFTER_ATTRIBUTE_EQUALS_SIGN:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly after the equals sign "
"following an attribute name; no attribute value"));
break;
case STATE_INSIDE_ATTRIBUTE_VALUE_SQ:
case STATE_INSIDE_ATTRIBUTE_VALUE_DQ:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly while inside an attribute "
"value"));
break;
case STATE_INSIDE_TEXT:
g_assert (context->tag_stack != NULL);
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly with elements still open - "
"'%s' was the last element opened"),
current_element (context));
break;
case STATE_AFTER_CLOSE_TAG_SLASH:
case STATE_INSIDE_CLOSE_TAG_NAME:
case STATE_AFTER_CLOSE_TAG_NAME:
set_error (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly inside the close tag for "
"element '%s'"), current_element (context));
break;
case STATE_INSIDE_PASSTHROUGH:
set_error_literal (context, error, G_MARKUP_ERROR_PARSE,
_("Document ended unexpectedly inside a comment or "
"processing instruction"));
break;
case STATE_ERROR:
default:
g_assert_not_reached ();
break;
}
context->parsing = FALSE;
return context->state != STATE_ERROR;
}
/**
* g_markup_parse_context_get_element:
* @context: a #GMarkupParseContext
*
* Retrieves the name of the currently open element.
*
* If called from the start_element or end_element handlers this will
* give the element_name as passed to those functions. For the parent
* elements, see g_markup_parse_context_get_element_stack().
*
* Returns: the name of the currently open element, or %NULL
*
* Since: 2.2
*/
G_CONST_RETURN gchar *
g_markup_parse_context_get_element (GMarkupParseContext *context)
{
g_return_val_if_fail (context != NULL, NULL);
if (context->tag_stack == NULL)
return NULL;
else
return current_element (context);
}
/**
* g_markup_parse_context_get_element_stack:
* @context: a #GMarkupParseContext
*
* Retrieves the element stack from the internal state of the parser.
*
* The returned #GSList is a list of strings where the first item is
* the currently open tag (as would be returned by
* g_markup_parse_context_get_element()) and the next item is its
* immediate parent.
*
* This function is intended to be used in the start_element and
* end_element handlers where g_markup_parse_context_get_element()
* would merely return the name of the element that is being
* processed.
*
* Returns: the element stack, which must not be modified
*
* Since: 2.16
*/
G_CONST_RETURN GSList *
g_markup_parse_context_get_element_stack (GMarkupParseContext *context)
{
g_return_val_if_fail (context != NULL, NULL);
return context->tag_stack;
}
/**
* g_markup_parse_context_get_position:
* @context: a #GMarkupParseContext
* @line_number: (allow-none): return location for a line number, or %NULL
* @char_number: (allow-none): return location for a char-on-line number, or %NULL
*
* Retrieves the current line number and the number of the character on
* that line. Intended for use in error messages; there are no strict
* semantics for what constitutes the "current" line number other than
* "the best number we could come up with for error messages."
*/
void
g_markup_parse_context_get_position (GMarkupParseContext *context,
gint *line_number,
gint *char_number)
{
g_return_if_fail (context != NULL);
if (line_number)
*line_number = context->line_number;
if (char_number)
*char_number = context->char_number;
}
/**
* g_markup_parse_context_get_user_data:
* @context: a #GMarkupParseContext
*
* Returns the user_data associated with @context.
*
* This will either be the user_data that was provided to
* g_markup_parse_context_new() or to the most recent call
* of g_markup_parse_context_push().
*
* Returns: the provided user_data. The returned data belongs to
* the markup context and will be freed when g_markup_context_free()
* is called.
*
* Since: 2.18
*/
gpointer
g_markup_parse_context_get_user_data (GMarkupParseContext *context)
{
return context->user_data;
}
/**
* g_markup_parse_context_push:
* @context: a #GMarkupParseContext
* @parser: a #GMarkupParser
* @user_data: user data to pass to #GMarkupParser functions
*
* Temporarily redirects markup data to a sub-parser.
*
* This function may only be called from the start_element handler of
* a #GMarkupParser. It must be matched with a corresponding call to
* g_markup_parse_context_pop() in the matching end_element handler
* (except in the case that the parser aborts due to an error).
*
* All tags, text and other data between the matching tags is
* redirected to the subparser given by @parser. @user_data is used
* as the user_data for that parser. @user_data is also passed to the
* error callback in the event that an error occurs. This includes
* errors that occur in subparsers of the subparser.
*
* The end tag matching the start tag for which this call was made is
* handled by the previous parser (which is given its own user_data)
* which is why g_markup_parse_context_pop() is provided to allow "one
* last access" to the @user_data provided to this function. In the
* case of error, the @user_data provided here is passed directly to
* the error callback of the subparser and g_markup_parse_context()
* should not be called. In either case, if @user_data was allocated
* then it ought to be freed from both of these locations.
*
* This function is not intended to be directly called by users
* interested in invoking subparsers. Instead, it is intended to be
* used by the subparsers themselves to implement a higher-level
* interface.
*
* As an example, see the following implementation of a simple
* parser that counts the number of tags encountered.
*
* |[
* typedef struct
* {
* gint tag_count;
* } CounterData;
*
* static void
* counter_start_element (GMarkupParseContext *context,
* const gchar *element_name,
* const gchar **attribute_names,
* const gchar **attribute_values,
* gpointer user_data,
* GError **error)
* {
* CounterData *data = user_data;
*
* data->tag_count++;
* }
*
* static void
* counter_error (GMarkupParseContext *context,
* GError *error,
* gpointer user_data)
* {
* CounterData *data = user_data;
*
* g_slice_free (CounterData, data);
* }
*
* static GMarkupParser counter_subparser =
* {
* counter_start_element,
* NULL,
* NULL,
* NULL,
* counter_error
* };
* ]|
*
* In order to allow this parser to be easily used as a subparser, the
* following interface is provided:
*
* |[
* void
* start_counting (GMarkupParseContext *context)
* {
* CounterData *data = g_slice_new (CounterData);
*
* data->tag_count = 0;
* g_markup_parse_context_push (context, &counter_subparser, data);
* }
*
* gint
* end_counting (GMarkupParseContext *context)
* {
* CounterData *data = g_markup_parse_context_pop (context);
* int result;
*
* result = data->tag_count;
* g_slice_free (CounterData, data);
*
* return result;
* }
* ]|
*
* The subparser would then be used as follows:
*
* |[
* static void start_element (context, element_name, ...)
* {
* if (strcmp (element_name, "count-these") == 0)
* start_counting (context);
*
* /* else, handle other tags... */
* }
*
* static void end_element (context, element_name, ...)
* {
* if (strcmp (element_name, "count-these") == 0)
* g_print ("Counted %d tags\n", end_counting (context));
*
* /* else, handle other tags... */
* }
* ]|
*
* Since: 2.18
**/
void
g_markup_parse_context_push (GMarkupParseContext *context,
const GMarkupParser *parser,
gpointer user_data)
{
GMarkupRecursionTracker *tracker;
tracker = g_slice_new (GMarkupRecursionTracker);
tracker->prev_element = context->subparser_element;
tracker->prev_parser = context->parser;
tracker->prev_user_data = context->user_data;
context->subparser_element = current_element (context);
context->parser = parser;
context->user_data = user_data;
context->subparser_stack = g_slist_prepend (context->subparser_stack,
tracker);
}
/**
* g_markup_parse_context_pop:
* @context: a #GMarkupParseContext
*
* Completes the process of a temporary sub-parser redirection.
*
* This function exists to collect the user_data allocated by a
* matching call to g_markup_parse_context_push(). It must be called
* in the end_element handler corresponding to the start_element
* handler during which g_markup_parse_context_push() was called.
* You must not call this function from the error callback -- the
* @user_data is provided directly to the callback in that case.
*
* This function is not intended to be directly called by users
* interested in invoking subparsers. Instead, it is intended to
* be used by the subparsers themselves to implement a higher-level
* interface.
*
* Returns: the user data passed to g_markup_parse_context_push()
*
* Since: 2.18
*/
gpointer
g_markup_parse_context_pop (GMarkupParseContext *context)
{
gpointer user_data;
if (!context->awaiting_pop)
possibly_finish_subparser (context);
g_assert (context->awaiting_pop);
context->awaiting_pop = FALSE;
/* valgrind friendliness */
user_data = context->held_user_data;
context->held_user_data = NULL;
return user_data;
}
static void
append_escaped_text (GString *str,
const gchar *text,
gssize length)
{
const gchar *p;
const gchar *end;
gunichar c;
p = text;
end = text + length;
while (p != end)
{
const gchar *next;
next = g_utf8_next_char (p);
switch (*p)
{
case '&':
g_string_append (str, "&");
break;
case '<':
g_string_append (str, "<");
break;
case '>':
g_string_append (str, ">");
break;
case '\'':
g_string_append (str, "'");
break;
case '"':
g_string_append (str, """);
break;
default:
c = g_utf8_get_char (p);
if ((0x1 <= c && c <= 0x8) ||
(0xb <= c && c <= 0xc) ||
(0xe <= c && c <= 0x1f) ||
(0x7f <= c && c <= 0x84) ||
(0x86 <= c && c <= 0x9f))
g_string_append_printf (str, "&#x%x;", c);
else
g_string_append_len (str, p, next - p);
break;
}
p = next;
}
}
/**
* g_markup_escape_text:
* @text: some valid UTF-8 text
* @length: length of @text in bytes, or -1 if the text is nul-terminated
*
* Escapes text so that the markup parser will parse it verbatim.
* Less than, greater than, ampersand, etc. are replaced with the
* corresponding entities. This function would typically be used
* when writing out a file to be parsed with the markup parser.
*
* Note that this function doesn't protect whitespace and line endings
* from being processed according to the XML rules for normalization
* of line endings and attribute values.
*
* Note also that this function will produce character references in
* the range of &#x1; ... &#x1f; for all control sequences
* except for tabstop, newline and carriage return. The character
* references in this range are not valid XML 1.0, but they are
* valid XML 1.1 and will be accepted by the GMarkup parser.
*
* Return value: a newly allocated string with the escaped text
*/
gchar*
g_markup_escape_text (const gchar *text,
gssize length)
{
GString *str;
g_return_val_if_fail (text != NULL, NULL);
if (length < 0)
length = strlen (text);
/* prealloc at least as long as original text */
str = g_string_sized_new (length);
append_escaped_text (str, text, length);
return g_string_free (str, FALSE);
}
/*
* find_conversion:
* @format: a printf-style format string
* @after: location to store a pointer to the character after
* the returned conversion. On a %NULL return, returns the
* pointer to the trailing NUL in the string
*
* Find the next conversion in a printf-style format string.
* Partially based on code from printf-parser.c,
* Copyright (C) 1999-2000, 2002-2003 Free Software Foundation, Inc.
*
* Return value: pointer to the next conversion in @format,
* or %NULL, if none.
*/
static const char *
find_conversion (const char *format,
const char **after)
{
const char *start = format;
const char *cp;
while (*start != '\0' && *start != '%')
start++;
if (*start == '\0')
{
*after = start;
return NULL;
}
cp = start + 1;
if (*cp == '\0')
{
*after = cp;
return NULL;
}
/* Test for positional argument. */
if (*cp >= '0' && *cp <= '9')
{
const char *np;
for (np = cp; *np >= '0' && *np <= '9'; np++)
;
if (*np == '$')
cp = np + 1;
}
/* Skip the flags. */
for (;;)
{
if (*cp == '\'' ||
*cp == '-' ||
*cp == '+' ||
*cp == ' ' ||
*cp == '#' ||
*cp == '0')
cp++;
else
break;
}
/* Skip the field width. */
if (*cp == '*')
{
cp++;
/* Test for positional argument. */
if (*cp >= '0' && *cp <= '9')
{
const char *np;
for (np = cp; *np >= '0' && *np <= '9'; np++)
;
if (*np == '$')
cp = np + 1;
}
}
else
{
for (; *cp >= '0' && *cp <= '9'; cp++)
;
}
/* Skip the precision. */
if (*cp == '.')
{
cp++;
if (*cp == '*')
{
/* Test for positional argument. */
if (*cp >= '0' && *cp <= '9')
{
const char *np;
for (np = cp; *np >= '0' && *np <= '9'; np++)
;
if (*np == '$')
cp = np + 1;
}
}
else
{
for (; *cp >= '0' && *cp <= '9'; cp++)
;
}
}
/* Skip argument type/size specifiers. */
while (*cp == 'h' ||
*cp == 'L' ||
*cp == 'l' ||
*cp == 'j' ||
*cp == 'z' ||
*cp == 'Z' ||
*cp == 't')
cp++;
/* Skip the conversion character. */
cp++;
*after = cp;
return start;
}
/**
* g_markup_vprintf_escaped:
* @format: printf() style format string
* @args: variable argument list, similar to vprintf()
*
* Formats the data in @args according to @format, escaping
* all string and character arguments in the fashion
* of g_markup_escape_text(). See g_markup_printf_escaped().
*
* Return value: newly allocated result from formatting
* operation. Free with g_free().
*
* Since: 2.4
*/
gchar *
g_markup_vprintf_escaped (const gchar *format,
va_list args)
{
GString *format1;
GString *format2;
GString *result = NULL;
gchar *output1 = NULL;
gchar *output2 = NULL;
const char *p, *op1, *op2;
va_list args2;
/* The technique here, is that we make two format strings that
* have the identical conversions in the identical order to the
* original strings, but differ in the text in-between. We
* then use the normal g_strdup_vprintf() to format the arguments
* with the two new format strings. By comparing the results,
* we can figure out what segments of the output come from
* the the original format string, and what from the arguments,
* and thus know what portions of the string to escape.
*
* For instance, for:
*
* g_markup_printf_escaped ("%s ate %d apples", "Susan & Fred", 5);
*
* We form the two format strings "%sX%dX" and %sY%sY". The results
* of formatting with those two strings are
*
* "%sX%dX" => "Susan & FredX5X"
* "%sY%dY" => "Susan & FredY5Y"
*
* To find the span of the first argument, we find the first position
* where the two arguments differ, which tells us that the first
* argument formatted to "Susan & Fred". We then escape that
* to "Susan & Fred" and join up with the intermediate portions
* of the format string and the second argument to get
* "Susan & Fred ate 5 apples".
*/
/* Create the two modified format strings
*/
format1 = g_string_new (NULL);
format2 = g_string_new (NULL);
p = format;
while (TRUE)
{
const char *after;
const char *conv = find_conversion (p, &after);
if (!conv)
break;
g_string_append_len (format1, conv, after - conv);
g_string_append_c (format1, 'X');
g_string_append_len (format2, conv, after - conv);
g_string_append_c (format2, 'Y');
p = after;
}
/* Use them to format the arguments
*/
G_VA_COPY (args2, args);
output1 = g_strdup_vprintf (format1->str, args);
if (!output1)
{
va_end (args2);
goto cleanup;
}
output2 = g_strdup_vprintf (format2->str, args2);
va_end (args2);
if (!output2)
goto cleanup;
result = g_string_new (NULL);
/* Iterate through the original format string again,
* copying the non-conversion portions and the escaped
* converted arguments to the output string.
*/
op1 = output1;
op2 = output2;
p = format;
while (TRUE)
{
const char *after;
const char *output_start;
const char *conv = find_conversion (p, &after);
char *escaped;
if (!conv) /* The end, after points to the trailing \0 */
{
g_string_append_len (result, p, after - p);
break;
}
g_string_append_len (result, p, conv - p);
output_start = op1;
while (*op1 == *op2)
{
op1++;
op2++;
}
escaped = g_markup_escape_text (output_start, op1 - output_start);
g_string_append (result, escaped);
g_free (escaped);
p = after;
op1++;
op2++;
}
cleanup:
g_string_free (format1, TRUE);
g_string_free (format2, TRUE);
g_free (output1);
g_free (output2);
if (result)
return g_string_free (result, FALSE);
else
return NULL;
}
/**
* g_markup_printf_escaped:
* @format: printf() style format string
* @Varargs: the arguments to insert in the format string
*
* Formats arguments according to @format, escaping
* all string and character arguments in the fashion
* of g_markup_escape_text(). This is useful when you
* want to insert literal strings into XML-style markup
* output, without having to worry that the strings
* might themselves contain markup.
*
* |[
* const char *store = "Fortnum & Mason";
* const char *item = "Tea";
* char *output;
*
* output = g_markup_printf_escaped ("<purchase>"
* "<store>%s</store>"
* "<item>%s</item>"
* "</purchase>",
* store, item);
* ]|
*
* Return value: newly allocated result from formatting
* operation. Free with g_free().
*
* Since: 2.4
*/
gchar *
g_markup_printf_escaped (const gchar *format, ...)
{
char *result;
va_list args;
va_start (args, format);
result = g_markup_vprintf_escaped (format, args);
va_end (args);
return result;
}
static gboolean
g_markup_parse_boolean (const char *string,
gboolean *value)
{
char const * const falses[] = { "false", "f", "no", "n", "0" };
char const * const trues[] = { "true", "t", "yes", "y", "1" };
int i;
for (i = 0; i < G_N_ELEMENTS (falses); i++)
{
if (g_ascii_strcasecmp (string, falses[i]) == 0)
{
if (value != NULL)
*value = FALSE;
return TRUE;
}
}
for (i = 0; i < G_N_ELEMENTS (trues); i++)
{
if (g_ascii_strcasecmp (string, trues[i]) == 0)
{
if (value != NULL)
*value = TRUE;
return TRUE;
}
}
return FALSE;
}
/**
* GMarkupCollectType:
* @G_MARKUP_COLLECT_INVALID: used to terminate the list of attributes
* to collect
* @G_MARKUP_COLLECT_STRING: collect the string pointer directly from
* the attribute_values[] array. Expects a parameter of type (const
* char **). If %G_MARKUP_COLLECT_OPTIONAL is specified and the
* attribute isn't present then the pointer will be set to %NULL
* @G_MARKUP_COLLECT_STRDUP: as with %G_MARKUP_COLLECT_STRING, but
* expects a parameter of type (char **) and g_strdup()s the
* returned pointer. The pointer must be freed with g_free()
* @G_MARKUP_COLLECT_BOOLEAN: expects a parameter of type (gboolean *)
* and parses the attribute value as a boolean. Sets %FALSE if the
* attribute isn't present. Valid boolean values consist of
* (case-insensitive) "false", "f", "no", "n", "0" and "true", "t",
* "yes", "y", "1"
* @G_MARKUP_COLLECT_TRISTATE: as with %G_MARKUP_COLLECT_BOOLEAN, but
* in the case of a missing attribute a value is set that compares
* equal to neither %FALSE nor %TRUE G_MARKUP_COLLECT_OPTIONAL is
* implied
* @G_MARKUP_COLLECT_OPTIONAL: can be bitwise ORed with the other fields.
* If present, allows the attribute not to appear. A default value
* is set depending on what value type is used
*
* A mixed enumerated type and flags field. You must specify one type
* (string, strdup, boolean, tristate). Additionally, you may optionally
* bitwise OR the type with the flag %G_MARKUP_COLLECT_OPTIONAL.
*
* It is likely that this enum will be extended in the future to
* support other types.
*/
/**
* g_markup_collect_attributes:
* @element_name: the current tag name
* @attribute_names: the attribute names
* @attribute_values: the attribute values
* @error: a pointer to a #GError or %NULL
* @first_type: the #GMarkupCollectType of the first attribute
* @first_attr: the name of the first attribute
* @...: a pointer to the storage location of the first attribute
* (or %NULL), followed by more types names and pointers, ending
* with %G_MARKUP_COLLECT_INVALID
*
* Collects the attributes of the element from the data passed to the
* #GMarkupParser start_element function, dealing with common error
* conditions and supporting boolean values.
*
* This utility function is not required to write a parser but can save
* a lot of typing.
*
* The @element_name, @attribute_names, @attribute_values and @error
* parameters passed to the start_element callback should be passed
* unmodified to this function.
*
* Following these arguments is a list of "supported" attributes to collect.
* It is an error to specify multiple attributes with the same name. If any
* attribute not in the list appears in the @attribute_names array then an
* unknown attribute error will result.
*
* The #GMarkupCollectType field allows specifying the type of collection
* to perform and if a given attribute must appear or is optional.
*
* The attribute name is simply the name of the attribute to collect.
*
* The pointer should be of the appropriate type (see the descriptions
* under #GMarkupCollectType) and may be %NULL in case a particular
* attribute is to be allowed but ignored.
*
* This function deals with issuing errors for missing attributes
* (of type %G_MARKUP_ERROR_MISSING_ATTRIBUTE), unknown attributes
* (of type %G_MARKUP_ERROR_UNKNOWN_ATTRIBUTE) and duplicate
* attributes (of type %G_MARKUP_ERROR_INVALID_CONTENT) as well
* as parse errors for boolean-valued attributes (again of type
* %G_MARKUP_ERROR_INVALID_CONTENT). In all of these cases %FALSE
* will be returned and @error will be set as appropriate.
*
* Return value: %TRUE if successful
*
* Since: 2.16
**/
gboolean
g_markup_collect_attributes (const gchar *element_name,
const gchar **attribute_names,
const gchar **attribute_values,
GError **error,
GMarkupCollectType first_type,
const gchar *first_attr,
...)
{
GMarkupCollectType type;
const gchar *attr;
guint64 collected;
int written;
va_list ap;
int i;
type = first_type;
attr = first_attr;
collected = 0;
written = 0;
va_start (ap, first_attr);
while (type != G_MARKUP_COLLECT_INVALID)
{
gboolean mandatory;
const gchar *value;
mandatory = !(type & G_MARKUP_COLLECT_OPTIONAL);
type &= (G_MARKUP_COLLECT_OPTIONAL - 1);
/* tristate records a value != TRUE and != FALSE
* for the case where the attribute is missing
*/
if (type == G_MARKUP_COLLECT_TRISTATE)
mandatory = FALSE;
for (i = 0; attribute_names[i]; i++)
if (i >= 40 || !(collected & (G_GUINT64_CONSTANT(1) << i)))
if (!strcmp (attribute_names[i], attr))
break;
/* ISO C99 only promises that the user can pass up to 127 arguments.
* Subtracting the first 4 arguments plus the final NULL and dividing
* by 3 arguments per collected attribute, we are left with a maximum
* number of supported attributes of (127 - 5) / 3 = 40.
*
* In reality, nobody is ever going to call us with anywhere close to
* 40 attributes to collect, so it is safe to assume that if i > 40
* then the user has given some invalid or repeated arguments. These
* problems will be caught and reported at the end of the function.
*
* We know at this point that we have an error, but we don't know
* what error it is, so just continue...
*/
if (i < 40)
collected |= (G_GUINT64_CONSTANT(1) << i);
value = attribute_values[i];
if (value == NULL && mandatory)
{
g_set_error (error, G_MARKUP_ERROR,
G_MARKUP_ERROR_MISSING_ATTRIBUTE,
"element '%s' requires attribute '%s'",
element_name, attr);
va_end (ap);
goto failure;
}
switch (type)
{
case G_MARKUP_COLLECT_STRING:
{
const char **str_ptr;
str_ptr = va_arg (ap, const char **);
if (str_ptr != NULL)
*str_ptr = value;
}
break;
case G_MARKUP_COLLECT_STRDUP:
{
char **str_ptr;
str_ptr = va_arg (ap, char **);
if (str_ptr != NULL)
*str_ptr = g_strdup (value);
}
break;
case G_MARKUP_COLLECT_BOOLEAN:
case G_MARKUP_COLLECT_TRISTATE:
if (value == NULL)
{
gboolean *bool_ptr;
bool_ptr = va_arg (ap, gboolean *);
if (bool_ptr != NULL)
{
if (type == G_MARKUP_COLLECT_TRISTATE)
/* constructivists rejoice!
* neither false nor true...
*/
*bool_ptr = -1;
else /* G_MARKUP_COLLECT_BOOLEAN */
*bool_ptr = FALSE;
}
}
else
{
if (!g_markup_parse_boolean (value, va_arg (ap, gboolean *)))
{
g_set_error (error, G_MARKUP_ERROR,
G_MARKUP_ERROR_INVALID_CONTENT,
"element '%s', attribute '%s', value '%s' "
"cannot be parsed as a boolean value",
element_name, attr, value);
va_end (ap);
goto failure;
}
}
break;
default:
g_assert_not_reached ();
}
type = va_arg (ap, GMarkupCollectType);
attr = va_arg (ap, const char *);
written++;
}
va_end (ap);
/* ensure we collected all the arguments */
for (i = 0; attribute_names[i]; i++)
if ((collected & (G_GUINT64_CONSTANT(1) << i)) == 0)
{
/* attribute not collected: could be caused by two things.
*
* 1) it doesn't exist in our list of attributes
* 2) it existed but was matched by a duplicate attribute earlier
*
* find out.
*/
int j;
for (j = 0; j < i; j++)
if (strcmp (attribute_names[i], attribute_names[j]) == 0)
/* duplicate! */
break;
/* j is now the first occurrence of attribute_names[i] */
if (i == j)
g_set_error (error, G_MARKUP_ERROR,
G_MARKUP_ERROR_UNKNOWN_ATTRIBUTE,
"attribute '%s' invalid for element '%s'",
attribute_names[i], element_name);
else
g_set_error (error, G_MARKUP_ERROR,
G_MARKUP_ERROR_INVALID_CONTENT,
"attribute '%s' given multiple times for element '%s'",
attribute_names[i], element_name);
goto failure;
}
return TRUE;
failure:
/* replay the above to free allocations */
type = first_type;
attr = first_attr;
va_start (ap, first_attr);
while (type != G_MARKUP_COLLECT_INVALID)
{
gpointer ptr;
ptr = va_arg (ap, gpointer);
if (ptr == NULL)
continue;
switch (type & (G_MARKUP_COLLECT_OPTIONAL - 1))
{
case G_MARKUP_COLLECT_STRDUP:
if (written)
g_free (*(char **) ptr);
case G_MARKUP_COLLECT_STRING:
*(char **) ptr = NULL;
break;
case G_MARKUP_COLLECT_BOOLEAN:
*(gboolean *) ptr = FALSE;
break;
case G_MARKUP_COLLECT_TRISTATE:
*(gboolean *) ptr = -1;
break;
}
type = va_arg (ap, GMarkupCollectType);
attr = va_arg (ap, const char *);
if (written)
written--;
}
va_end (ap);
return FALSE;
}
Submit an article or tip