xdgmime.c

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  if (need_reread)
    {
      global_hash = _xdg_glob_hash_new ();
      global_magic = _xdg_mime_magic_new ();
      alias_list = _xdg_mime_alias_list_new ();
      parent_list = _xdg_mime_parent_list_new ();

      xdg_run_command_on_dirs ((XdgDirectoryFunc) xdg_mime_init_from_directory,
			       NULL);

      need_reread = FALSE;
    }
}

const char *
xdg_mime_get_mime_type_for_data (const void *data,
				 size_t      len)
{
  const char *mime_type;

  xdg_mime_init ();

  if (_xdg_mime_caches)
    return _xdg_mime_cache_get_mime_type_for_data (data, len);

  mime_type = _xdg_mime_magic_lookup_data (global_magic, data, len, NULL, 0);

  if (mime_type)
    return mime_type;

  return XDG_MIME_TYPE_UNKNOWN;
}

const char *
xdg_mime_get_mime_type_for_file (const char  *file_name,
                                 struct stat *statbuf)
{
  const char *mime_type;
  /* Used to detect whether multiple MIME types match file_name */
  const char *mime_types[2];
  FILE *file;
  unsigned char *data;
  int max_extent;
  int bytes_read;
  struct stat buf;
  const char *base_name;
  int n;

  if (file_name == NULL)
    return NULL;
  if (! _xdg_utf8_validate (file_name))
    return NULL;

  xdg_mime_init ();

  if (_xdg_mime_caches)
    return _xdg_mime_cache_get_mime_type_for_file (file_name, statbuf);

  base_name = _xdg_get_base_name (file_name);
  n = _xdg_glob_hash_lookup_file_name (global_hash, base_name, mime_types, 2);

  if (n == 1)
    return mime_types[0];

  if (!statbuf)
    {
      if (stat (file_name, &buf) != 0)
	return XDG_MIME_TYPE_UNKNOWN;

      statbuf = &buf;
    }

  if (!S_ISREG (statbuf->st_mode))
    return XDG_MIME_TYPE_UNKNOWN;

  /* FIXME: Need to make sure that max_extent isn't totally broken.  This could
   * be large and need getting from a stream instead of just reading it all
   * in. */
  max_extent = _xdg_mime_magic_get_buffer_extents (global_magic);
  data = malloc (max_extent);
  if (data == NULL)
    return XDG_MIME_TYPE_UNKNOWN;
        
  file = fopen (file_name, "r");
  if (file == NULL)
    {
      free (data);
      return XDG_MIME_TYPE_UNKNOWN;
    }

  bytes_read = fread (data, 1, max_extent, file);
  if (ferror (file))
    {
      free (data);
      fclose (file);
      return XDG_MIME_TYPE_UNKNOWN;
    }

  mime_type = _xdg_mime_magic_lookup_data (global_magic, data, bytes_read,
					   mime_types, n);

  free (data);
  fclose (file);

  if (mime_type)
    return mime_type;

  return XDG_MIME_TYPE_UNKNOWN;
}

const char *
xdg_mime_get_mime_type_from_file_name (const char *file_name)
{
  const char *mime_types[2];

  xdg_mime_init ();

  if (_xdg_mime_caches)
    return _xdg_mime_cache_get_mime_type_from_file_name (file_name);

  if (_xdg_glob_hash_lookup_file_name (global_hash, file_name, mime_types, 2) == 1)
    return mime_types[0];
  else
    return XDG_MIME_TYPE_UNKNOWN;
}

int
xdg_mime_is_valid_mime_type (const char *mime_type)
{
  /* FIXME: We should make this a better test
   */
  return _xdg_utf8_validate (mime_type);
}

void
xdg_mime_shutdown (void)
{
  XdgCallbackList *list;

  /* FIXME: Need to make this (and the whole library) thread safe */
  if (dir_time_list)
    {
      xdg_dir_time_list_free (dir_time_list);
      dir_time_list = NULL;
    }
	
  if (global_hash)
    {
      _xdg_glob_hash_free (global_hash);
      global_hash = NULL;
    }
  if (global_magic)
    {
      _xdg_mime_magic_free (global_magic);
      global_magic = NULL;
    }

  if (alias_list)
    {
      _xdg_mime_alias_list_free (alias_list);
      alias_list = NULL;
    }

  if (parent_list)
    {
      _xdg_mime_parent_list_free (parent_list);
      parent_list = NULL;
    }

  if (_xdg_mime_caches)
    {
      int i;
      for (i = 0; i < n_caches; i++)
        _xdg_mime_cache_unref (_xdg_mime_caches[i]);
      free (_xdg_mime_caches);
      _xdg_mime_caches = NULL;
      n_caches = 0;
    }

  for (list = callback_list; list; list = list->next)
    (list->callback) (list->data);

  need_reread = TRUE;
}

int
xdg_mime_get_max_buffer_extents (void)
{
  xdg_mime_init ();
  
  if (_xdg_mime_caches)
    return _xdg_mime_cache_get_max_buffer_extents ();

  return _xdg_mime_magic_get_buffer_extents (global_magic);
}

static const char *
_xdg_mime_unalias_mime_type (const char *mime_type)
{
  const char *lookup;

  if (_xdg_mime_caches)
    return _xdg_mime_cache_unalias_mime_type (mime_type);

  if ((lookup = _xdg_mime_alias_list_lookup (alias_list, mime_type)) != NULL)
    return lookup;

  return mime_type;
}

const char *
xdg_mime_unalias_mime_type (const char *mime_type)
{
  xdg_mime_init ();

  return _xdg_mime_unalias_mime_type (mime_type);
}

int
_xdg_mime_mime_type_equal (const char *mime_a,
			   const char *mime_b)
{
  const char *unalias_a, *unalias_b;

  unalias_a = _xdg_mime_unalias_mime_type (mime_a);
  unalias_b = _xdg_mime_unalias_mime_type (mime_b);

  if (strcmp (unalias_a, unalias_b) == 0)
    return 1;

  return 0;
}

int
xdg_mime_mime_type_equal (const char *mime_a,
			  const char *mime_b)
{
  xdg_mime_init ();

  return _xdg_mime_mime_type_equal (mime_a, mime_b);
}

int
_xdg_mime_media_type_equal (const char *mime_a,
			    const char *mime_b)
{
  char *sep;

  xdg_mime_init ();

  sep = strchr (mime_a, '/');
  
  if (sep && strncmp (mime_a, mime_b, sep - mime_a + 1) == 0)
    return 1;

  return 0;
}

int
xdg_mime_media_type_equal (const char *mime_a,
			   const char *mime_b)
{
  xdg_mime_init ();

  return _xdg_mime_media_type_equal (mime_a, mime_b);
}

#if 0
static int
xdg_mime_is_super_type (const char *mime)
{
  int length;
  const char *type;

  length = strlen (mime);
  type = &(mime[length - 2]);

  if (strcmp (type, "/*") == 0)
    return 1;

  return 0;
}
#endif

int
_xdg_mime_mime_type_subclass (const char *mime,
			      const char *base)
{
  const char *umime, *ubase;
  const char **parents;

  if (_xdg_mime_caches)
    return _xdg_mime_cache_mime_type_subclass (mime, base);

  umime = _xdg_mime_unalias_mime_type (mime);
  ubase = _xdg_mime_unalias_mime_type (base);

  if (strcmp (umime, ubase) == 0)
    return 1;

#if 0  
  /* Handle supertypes */
  if (xdg_mime_is_super_type (ubase) &&
      _xdg_mime_media_type_equal (umime, ubase))
    return 1;
#endif

  /*  Handle special cases text/plain and application/octet-stream */
  if (strcmp (ubase, "text/plain") == 0 && 
      strncmp (umime, "text/", 5) == 0)
    return 1;

  if (strcmp (ubase, "application/octet-stream") == 0)
    return 1;
  
  parents = _xdg_mime_parent_list_lookup (parent_list, umime);
  for (; parents && *parents; parents++)
    {
      if (_xdg_mime_mime_type_subclass (*parents, ubase))
	return 1;
    }

  return 0;
}

int
xdg_mime_mime_type_subclass (const char *mime,
			     const char *base)
{
  xdg_mime_init ();

  return _xdg_mime_mime_type_subclass (mime, base);
}

char **
xdg_mime_list_mime_parents (const char *mime)
{
  const char **parents;
  char **result;
  int i, n;

  if (_xdg_mime_caches)
    return _xdg_mime_cache_list_mime_parents (mime);

  parents = xdg_mime_get_mime_parents (mime);

  if (!parents)
    return NULL;

  for (i = 0; parents[i]; i++) ;
  
  n = (i + 1) * sizeof (char *);
  result = (char **) malloc (n);
  memcpy (result, parents, n);

  return result;
}

const char **
xdg_mime_get_mime_parents (const char *mime)
{
  const char *umime;

  xdg_mime_init ();

  umime = _xdg_mime_unalias_mime_type (mime);

  return _xdg_mime_parent_list_lookup (parent_list, umime);
}

void 
xdg_mime_dump (void)
{
  printf ("*** ALIASES ***\n\n");
  _xdg_mime_alias_list_dump (alias_list);
  printf ("\n*** PARENTS ***\n\n");
  _xdg_mime_parent_list_dump (parent_list);
  printf ("\n*** CACHE ***\n\n");
  _xdg_glob_hash_dump (global_hash);
}


/* Registers a function to be called every time the mime database reloads its files
 */
int
xdg_mime_register_reload_callback (XdgMimeCallback  callback,
				   void            *data,
				   XdgMimeDestroy   destroy)
{
  XdgCallbackList *list_el;
  static int callback_id = 1;

  /* Make a new list element */
  list_el = calloc (1, sizeof (XdgCallbackList));
  list_el->callback_id = callback_id;
  list_el->callback = callback;
  list_el->data = data;
  list_el->destroy = destroy;
  list_el->next = callback_list;
  if (list_el->next)
    list_el->next->prev = list_el;

  callback_list = list_el;
  callback_id ++;

  return callback_id - 1;
}

void
xdg_mime_remove_callback (int callback_id)
{
  XdgCallbackList *list;

  for (list = callback_list; list; list = list->next)
    {
      if (list->callback_id == callback_id)
	{
	  if (list->next)
	    list->next = list->prev;

	  if (list->prev)
	    list->prev->next = list->next;
	  else
	    callback_list = list->next;

	  /* invoke the destroy handler */
	  (list->destroy) (list->data);
	  free (list);
	  return;
	}
    }
}