pango-markup.c

GTK+-2.0源码之pango-1.15.6.tar.gz

		  /* set next range_start to include this char */
		  range_start = p;
		}

	      /* reset range_end */
	      range_end = NULL;
	    }
	  else if (c == md->accel_marker)
	    {
	      range_end = p;
	    }

	  p = g_utf8_next_char (p);
	}

      if (range_end)
	{
	  g_string_append_len (md->text,
			       range_start,
			       range_end - range_start);
	  md->index += range_end - range_start;
	}
      else
	{
	  g_string_append_len (md->text,
			       range_start,
			       end - range_start);
	  md->index += end - range_start;
	}

      if (md->attr_list != NULL && uline_index >= 0)
	{
	  /* Add the underline indicating the accelerator */
	  PangoAttribute *attr;

	  attr = pango_attr_underline_new (PANGO_UNDERLINE_LOW);

	  attr->start_index = uline_index;
	  attr->end_index = uline_index + uline_len;

	  pango_attr_list_change (md->attr_list, attr);
	}
    }
}

static gboolean
xml_isspace (char c)
{
  return c == ' ' || c == '\t' || c == '\n' || c == '\r';
}

static const GMarkupParser pango_markup_parser = {
  start_element_handler,
  end_element_handler,
  text_handler,
  NULL,
  NULL
};

/**
 * pango_parse_markup:
 * @markup_text: markup to parse (see <link linkend="PangoMarkupFormat">markup format</link>)
 * @length: length of @markup_text, or -1 if nul-terminated
 * @accel_marker: character that precedes an accelerator, or 0 for none
 * @attr_list: address of return location for a #PangoAttrList, or %NULL
 * @text: address of return location for text with tags stripped, or %NULL
 * @accel_char: address of return location for accelerator char, or %NULL
 * @error: address of return location for errors, or %NULL
 *
 *
 * Parses marked-up text (see
 * <link linkend="PangoMarkupFormat">markup format</link>) to create
 * a plain-text string and an attribute list.
 *
 * If @accel_marker is nonzero, the given character will mark the
 * character following it as an accelerator. For example, @accel_marker
 * might be an ampersand or underscore. All characters marked
 * as an accelerator will receive a %PANGO_UNDERLINE_LOW attribute,
 * and the first character so marked will be returned in @accel_char.
 * Two @accel_marker characters following each other produce a single
 * literal @accel_marker character.
 *
 * Return value: %FALSE if @error is set, otherwise %TRUE
 **/
gboolean
pango_parse_markup (const char                 *markup_text,
		    int                         length,
		    gunichar                    accel_marker,
		    PangoAttrList             **attr_list,
		    char                      **text,
		    gunichar                   *accel_char,
		    GError                    **error)
{
  GMarkupParseContext *context = NULL;
  MarkupData *md = NULL;
  gboolean needs_root = TRUE;
  GSList *tmp_list;
  const char *p;
  const char *end;

  g_return_val_if_fail (markup_text != NULL, FALSE);

  md = g_slice_new (MarkupData);

  /* Don't bother creating these if they weren't requested;
   * might be useful e.g. if you just want to validate
   * some markup.
   */
  if (attr_list)
    md->attr_list = pango_attr_list_new ();
  else
    md->attr_list = NULL;

  md->text = g_string_new (NULL);

  if (accel_char)
    *accel_char = 0;

  md->accel_marker = accel_marker;
  md->accel_char = 0;

  md->index = 0;
  md->tag_stack = NULL;
  md->to_apply = NULL;

  context = g_markup_parse_context_new (&pango_markup_parser,
					0, md, NULL);

  if (length < 0)
    length = strlen (markup_text);

  p = markup_text;
  end = markup_text + length;
  while (p != end && xml_isspace (*p))
    ++p;

  if (end - p >= 8 && strncmp (p, "<markup>", 8) == 0)
     needs_root = FALSE;

  if (needs_root)
    if (!g_markup_parse_context_parse (context,
				       "<markup>",
				       -1,
				       error))
      goto error;


  if (!g_markup_parse_context_parse (context,
				     markup_text,
				     length,
				     error))
    goto error;

  if (needs_root)
    if (!g_markup_parse_context_parse (context,
				       "</markup>",
				       -1,
				       error))
      goto error;

  if (!g_markup_parse_context_end_parse (context, error))
    goto error;

  g_markup_parse_context_free (context);

  if (md->attr_list)
    {
      /* The apply list has the most-recently-closed tags first;
       * we want to apply the least-recently-closed tag last.
       */
      tmp_list = md->to_apply;
      while (tmp_list != NULL)
	{
	  PangoAttribute *attr = tmp_list->data;

	  /* Innermost tags before outermost */
	  pango_attr_list_change (md->attr_list, attr);

	  tmp_list = g_slist_next (tmp_list);
	}
      g_slist_free (md->to_apply);
      md->to_apply = NULL;
    }

  if (attr_list)
    *attr_list = md->attr_list;

  if (text)
    *text = g_string_free (md->text, FALSE);
  else
    g_string_free (md->text, TRUE);

  if (accel_char)
    *accel_char = md->accel_char;

  g_assert (md->tag_stack == NULL);

  g_slice_free (MarkupData, md);

  return TRUE;

 error:
  g_slist_foreach (md->tag_stack, (GFunc) open_tag_free, NULL);
  g_slist_free (md->tag_stack);
  g_slist_foreach (md->to_apply, (GFunc) pango_attribute_destroy, NULL);
  g_slist_free (md->to_apply);
  g_string_free (md->text, TRUE);

  if (md->attr_list)
    pango_attr_list_unref (md->attr_list);

  g_slice_free (MarkupData, md);

  if (context)
    g_markup_parse_context_free (context);

  return FALSE;
}

static void
set_bad_attribute (GError             **error,
		   GMarkupParseContext *context,
		   const char          *element_name,
		   const char          *attribute_name)
{
  gint line_number, char_number;

  g_markup_parse_context_get_position (context,
				       &line_number, &char_number);

  g_set_error (error,
	       G_MARKUP_ERROR,
	       G_MARKUP_ERROR_UNKNOWN_ATTRIBUTE,
	       _("Tag '%s' does not support attribute '%s' on line %d char %d"),
	       element_name,
	       attribute_name,
	       line_number, char_number);
}

static void
add_attribute (OpenTag        *ot,
	       PangoAttribute *attr)
{
  if (ot == NULL)
    pango_attribute_destroy (attr);
  else
    ot->attrs = g_slist_prepend (ot->attrs, attr);
}

#define CHECK_NO_ATTRS(elem) G_STMT_START {                    \
	 if (*names != NULL) {                                 \
	   set_bad_attribute (error, context, (elem), *names); \
	   return FALSE;                                       \
	 } }G_STMT_END

static gboolean
b_parse_func        (MarkupData            *md,
		     OpenTag               *tag,
		     const gchar          **names,
		     const gchar          **values,
		     GMarkupParseContext   *context,
		     GError               **error)
{
  CHECK_NO_ATTRS("b");
  add_attribute (tag, pango_attr_weight_new (PANGO_WEIGHT_BOLD));
  return TRUE;
}

static gboolean
big_parse_func      (MarkupData            *md,
		     OpenTag               *tag,
		     const gchar          **names,
		     const gchar          **values,
		     GMarkupParseContext   *context,
		     GError               **error)
{
  CHECK_NO_ATTRS("big");

  /* Grow text one level */
  if (tag)
    {
      tag->scale_level_delta += 1;
      tag->scale_level += 1;
    }

  return TRUE;
}

static gboolean
parse_absolute_size (OpenTag               *tag,
		     const char            *size)
{
  SizeLevel level = Medium;
  double factor;

  if (strcmp (size, "xx-small") == 0)
    level = XXSmall;
  else if (strcmp (size, "x-small") == 0)
    level = XSmall;
  else if (strcmp (size, "small") == 0)
    level = Small;
  else if (strcmp (size, "medium") == 0)
    level = Medium;
  else if (strcmp (size, "large") == 0)
    level = Large;
  else if (strcmp (size, "x-large") == 0)
    level = XLarge;
  else if (strcmp (size, "xx-large") == 0)
    level = XXLarge;
  else
    return FALSE;

  /* This is "absolute" in that it's relative to the base font,
   * but not to sizes created by any other tags
   */
  factor = scale_factor (level, 1.0);
  add_attribute (tag, pango_attr_scale_new (factor));
  if (tag)
    open_tag_set_absolute_font_scale (tag, factor);

  return TRUE;
}

/* a string compare func that ignores '-' vs '_' differences */
static gint
attr_strcmp (gconstpointer pa,
	     gconstpointer pb)
{
  const char *a = pa;
  const char *b = pb;

  int ca;
  int cb;

  while (*a && *b)
    {
      ca = *a++;
      cb = *b++;

      if (ca == cb)
	continue;

      ca = ca == '_' ? '-' : ca;
      cb = cb == '_' ? '-' : cb;

      if (ca != cb)
	return cb - ca;
    }

  ca = *a;
  cb = *b;

  return cb - ca;
}

static gboolean
span_parse_int (const char *attr_name,
		const char *attr_val,
		int *val,
		int line_number,
		GError **error)
{
  const char *end = attr_val;

  if (!pango_scan_int (&end, val) || *end != '\0')
    {
      g_set_error (error,
		   G_MARKUP_ERROR,
		   G_MARKUP_ERROR_INVALID_CONTENT,
		   _("Value of '%s' attribute on <span> tag "
		     "on line %d could not be parsed; "
		     "should be an integer, not '%s'"),
		   attr_name, line_number, attr_val);
      return FALSE;
    }

  return TRUE;
}

static gboolean
span_parse_boolean (const char *attr_name,
		    const char *attr_val,
		    gboolean *val,
		    int line_number,
		    GError **error)
{
  const char *end = attr_val;

  if (strcmp (attr_val, "true") == 0 ||
      strcmp (attr_val, "yes") == 0 ||
      strcmp (attr_val, "t") == 0 ||
      strcmp (attr_val, "y") == 0)
    *val = TRUE;
  else if (strcmp (attr_val, "false") == 0 ||
	   strcmp (attr_val, "no") == 0 ||
	   strcmp (attr_val, "f") == 0 ||
	   strcmp (attr_val, "n") == 0)
    *val = FALSE;
  else
    {
      g_set_error (error,
		   G_MARKUP_ERROR,
		   G_MARKUP_ERROR_INVALID_CONTENT,
		   _("Value of '%s' attribute on <span> tag "
		     "line %d should have one of "
		     "'true/yes/t/y' or 'false/no/f/n': '%s' is not valid"),
		   attr_name, line_number, attr_val);
      return FALSE;
    }

  return TRUE;
}

static gboolean
span_parse_color (const char *attr_name,
		  const char *attr_val,
		  PangoColor *color,
		  int line_number,
		  GError **error)
{
  if (!pango_color_parse (color, attr_val))
    {
      g_set_error (error,
		   G_MARKUP_ERROR,
		   G_MARKUP_ERROR_INVALID_CONTENT,
		   _("Value of '%s' attribute on <span> tag "
		     "on line %d could not be parsed; "
		     "should be a color specification, not '%s'"),
		   attr_name, line_number, attr_val);
      return FALSE;
    }

  return TRUE;
}

static gboolean
span_parse_enum (const char *attr_name,
		 const char *attr_val,
		 GType type,
		 int *val,
		 int line_number,
		 GError **error)
{
  char *possible_values = NULL;

  if (!pango_parse_enum (type, attr_val, val, FALSE, &possible_values))
    {
      g_set_error (error,
		   G_MARKUP_ERROR,
		   G_MARKUP_ERROR_INVALID_CONTENT,
		   _("'%s' is not a valid value for the '%s' "
		     "attribute on <span> tag, line %d; valid "
		     "values are %s"),
		   attr_val, attr_name, line_number, possible_values);
      g_free (possible_values);
      return FALSE;
    }

  return TRUE;
}

static gboolean
span_parse_func     (MarkupData            *md,
		     OpenTag               *tag,
		     const gchar          **names,
		     const gchar          **values,
		     GMarkupParseContext   *context,
		     GError               **error)
{
  int line_number, char_number;
  int i;

  const char *family = NULL;
  const char *size = NULL;
  const char *style = NULL;
  const char *weight = NULL;
  const char *variant = NULL;
  const char *stretch = NULL;
  const char *desc = NULL;
  const char *foreground = NULL;
  const char *background = NULL;
  const char *underline = NULL;
  const char *underline_color = NULL;
  const char *strikethrough = NULL;
  const char *strikethrough_color = NULL;
  const char *rise = NULL;
  const char *letter_spacing = NULL;
  const char *lang = NULL;
  const char *fallback = NULL;
  const char *gravity = NULL;