gio/gloadableicon.c

   1 /* GIO - GLib Input, Output and Streaming Library
   2  *
   3  * Copyright (C) 2006-2007 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: Alexander Larsson <alexl@redhat.com>
  21  */
  22
  23 #include "config.h"
  24 #include "gasyncresult.h"
  25 #include "gsimpleasyncresult.h"
  26 #include "gicon.h"
  27 #include "gloadableicon.h"
  28 #include "glibintl.h"
  29
  30
  31 /**
  32  * SECTION:gloadableicon
  33  * @short_description: Loadable Icons
  34  * @include: gio/gio.h
  35  * @see_also: #GIcon, #GThemedIcon
  36  *
  37  * Extends the #GIcon interface and adds the ability to
  38  * load icons from streams.
  39  **/
  40
  41 static void          g_loadable_icon_real_load_async  (GLoadableIcon        *icon,
  42                                                        int                   size,
  43                                                        GCancellable         *cancellable,
  44                                                        GAsyncReadyCallback   callback,
  45                                                        gpointer              user_data);
  46 static GInputStream *g_loadable_icon_real_load_finish (GLoadableIcon        *icon,
  47                                                        GAsyncResult         *res,
  48                                                        char                **type,
  49                                                        GError              **error);
  50
  51 typedef GLoadableIconIface GLoadableIconInterface;
  52 G_DEFINE_INTERFACE(GLoadableIcon, g_loadable_icon, G_TYPE_ICON)
  53
  54 static void
  55 g_loadable_icon_default_init (GLoadableIconIface *iface)
  56 {
  57   iface->load_async = g_loadable_icon_real_load_async;
  58   iface->load_finish = g_loadable_icon_real_load_finish;
  59 }
  60
  61 /**
  62  * g_loadable_icon_load:
  63  * @icon: a #GLoadableIcon.
  64  * @size: an integer.
  65  * @type: (out) (allow-none): a location to store the type of the
  66  *        loaded icon, %NULL to ignore.
  67  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
  68  * @error: a #GError location to store the error occurring, or %NULL to
  69  * ignore.
  70  *
  71  * Loads a loadable icon. For the asynchronous version of this function,
  72  * see g_loadable_icon_load_async().
  73  *
  74  * Returns: (transfer full): a #GInputStream to read the icon from.
  75  **/
  76 GInputStream *
  77 g_loadable_icon_load (GLoadableIcon  *icon,
  78                       int             size,
  79                       char          **type,
  80                       GCancellable   *cancellable,
  81                       GError        **error)
  82 {
  83   GLoadableIconIface *iface;
  84
  85   g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
  86
  87   iface = G_LOADABLE_ICON_GET_IFACE (icon);
  88
  89   return (* iface->load) (icon, size, type, cancellable, error);
  90 }
  91
  92 /**
  93  * g_loadable_icon_load_async:
  94  * @icon: a #GLoadableIcon.
  95  * @size: an integer.
  96  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
  97  * @callback: (scope async): a #GAsyncReadyCallback to call when the
  98  *            request is satisfied
  99  * @user_data: (closure): the data to pass to callback function
 100  *
 101  * Loads an icon asynchronously. To finish this function, see
 102  * g_loadable_icon_load_finish(). For the synchronous, blocking
 103  * version of this function, see g_loadable_icon_load().
 104  **/
 105 void
 106 g_loadable_icon_load_async (GLoadableIcon       *icon,
 107                             int                  size,
 108                             GCancellable        *cancellable,
 109                             GAsyncReadyCallback  callback,
 110                             gpointer             user_data)
 111 {
 112   GLoadableIconIface *iface;
 113
 114   g_return_if_fail (G_IS_LOADABLE_ICON (icon));
 115
 116   iface = G_LOADABLE_ICON_GET_IFACE (icon);
 117
 118   (* iface->load_async) (icon, size, cancellable, callback, user_data);
 119 }
 120
 121 /**
 122  * g_loadable_icon_load_finish:
 123  * @icon: a #GLoadableIcon.
 124  * @res: a #GAsyncResult.
 125  * @type: a location to store the type of the loaded icon, %NULL to ignore.
 126  * @error: a #GError location to store the error occurring, or %NULL to
 127  * ignore.
 128  *
 129  * Finishes an asynchronous icon load started in g_loadable_icon_load_async().
 130  *
 131  * Returns: (transfer full): a #GInputStream to read the icon from.
 132  **/
 133 GInputStream *
 134 g_loadable_icon_load_finish (GLoadableIcon  *icon,
 135                              GAsyncResult   *res,
 136                              char          **type,
 137                              GError        **error)
 138 {
 139   GLoadableIconIface *iface;
 140
 141   g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
 142   g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
 143
 144   if (G_IS_SIMPLE_ASYNC_RESULT (res))
 145     {
 146       GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res);
 147       if (g_simple_async_result_propagate_error (simple, error))
 148         return NULL;
 149     }
 150
 151   iface = G_LOADABLE_ICON_GET_IFACE (icon);
 152
 153   return (* iface->load_finish) (icon, res, type, error);
 154 }
 155
 156 /********************************************
 157  *   Default implementation of async load   *
 158  ********************************************/
 159
 160 typedef struct {
 161   int size;
 162   char *type;
 163   GInputStream *stream;
 164 } LoadData;
 165
 166 static void
 167 load_data_free (LoadData *data)
 168 {
 169   if (data->stream)
 170     g_object_unref (data->stream);
 171   g_free (data->type);
 172   g_free (data);
 173 }
 174
 175 static void
 176 load_async_thread (GSimpleAsyncResult *res,
 177                    GObject            *object,
 178                    GCancellable       *cancellable)
 179 {
 180   GLoadableIconIface *iface;
 181   GInputStream *stream;
 182   LoadData *data;
 183   GError *error = NULL;
 184   char *type = NULL;
 185
 186   data = g_simple_async_result_get_op_res_gpointer (res);
 187
 188   iface = G_LOADABLE_ICON_GET_IFACE (object);
 189   stream = iface->load (G_LOADABLE_ICON (object), data->size, &type, cancellable, &error);
 190
 191   if (stream == NULL)
 192     {
 193       g_simple_async_result_take_error (res, error);
 194     }
 195   else
 196     {
 197       data->stream = stream;
 198       data->type = type;
 199     }
 200 }
 201
 202
 203
 204 static void
 205 g_loadable_icon_real_load_async (GLoadableIcon       *icon,
 206                                  int                  size,
 207                                  GCancellable        *cancellable,
 208                                  GAsyncReadyCallback  callback,
 209                                  gpointer             user_data)
 210 {
 211   GSimpleAsyncResult *res;
 212   LoadData *data;
 213
 214   res = g_simple_async_result_new (G_OBJECT (icon), callback, user_data, g_loadable_icon_real_load_async);
 215   data = g_new0 (LoadData, 1);
 216   g_simple_async_result_set_op_res_gpointer (res, data, (GDestroyNotify) load_data_free);
 217   g_simple_async_result_run_in_thread (res, load_async_thread, 0, cancellable);
 218   g_object_unref (res);
 219 }
 220
 221 static GInputStream *
 222 g_loadable_icon_real_load_finish (GLoadableIcon        *icon,
 223                                   GAsyncResult         *res,
 224                                   char                **type,
 225                                   GError              **error)
 226 {
 227   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res);
 228   LoadData *data;
 229
 230   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_loadable_icon_real_load_async);
 231
 232   data = g_simple_async_result_get_op_res_gpointer (simple);
 233
 234   if (type)
 235     {
 236       *type = data->type;
 237       data->type = NULL;
 238     }
 239
 240   return g_object_ref (data->stream);
 241 }