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, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: Alexander Larsson <alexl@redhat.com>
  19  */
  20
  21 #include "config.h"
  22 #include "gicon.h"
  23 #include "gloadableicon.h"
  24 #include "gasyncresult.h"
  25 #include "gtask.h"
  26 #include "glibintl.h"
  27
  28
  29 /**
  30  * SECTION:gloadableicon
  31  * @short_description: Loadable Icons
  32  * @include: gio/gio.h
  33  * @see_also: #GIcon, #GThemedIcon
  34  *
  35  * Extends the #GIcon interface and adds the ability to
  36  * load icons from streams.
  37  **/
  38
  39 static void          g_loadable_icon_real_load_async  (GLoadableIcon        *icon,
  40                                                        int                   size,
  41                                                        GCancellable         *cancellable,
  42                                                        GAsyncReadyCallback   callback,
  43                                                        gpointer              user_data);
  44 static GInputStream *g_loadable_icon_real_load_finish (GLoadableIcon        *icon,
  45                                                        GAsyncResult         *res,
  46                                                        char                **type,
  47                                                        GError              **error);
  48
  49 typedef GLoadableIconIface GLoadableIconInterface;
  50 G_DEFINE_INTERFACE(GLoadableIcon, g_loadable_icon, G_TYPE_ICON)
  51
  52 static void
  53 g_loadable_icon_default_init (GLoadableIconIface *iface)
  54 {
  55   iface->load_async = g_loadable_icon_real_load_async;
  56   iface->load_finish = g_loadable_icon_real_load_finish;
  57 }
  58
  59 /**
  60  * g_loadable_icon_load:
  61  * @icon: a #GLoadableIcon.
  62  * @size: an integer.
  63  * @type: (out) (allow-none): a location to store the type of the
  64  *        loaded icon, %NULL to ignore.
  65  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
  66  * @error: a #GError location to store the error occurring, or %NULL to
  67  * ignore.
  68  *
  69  * Loads a loadable icon. For the asynchronous version of this function,
  70  * see g_loadable_icon_load_async().
  71  *
  72  * Returns: (transfer full): a #GInputStream to read the icon from.
  73  **/
  74 GInputStream *
  75 g_loadable_icon_load (GLoadableIcon  *icon,
  76                       int             size,
  77                       char          **type,
  78                       GCancellable   *cancellable,
  79                       GError        **error)
  80 {
  81   GLoadableIconIface *iface;
  82
  83   g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
  84
  85   iface = G_LOADABLE_ICON_GET_IFACE (icon);
  86
  87   return (* iface->load) (icon, size, type, cancellable, error);
  88 }
  89
  90 /**
  91  * g_loadable_icon_load_async:
  92  * @icon: a #GLoadableIcon.
  93  * @size: an integer.
  94  * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
  95  * @callback: (scope async): a #GAsyncReadyCallback to call when the
  96  *            request is satisfied
  97  * @user_data: (closure): the data to pass to callback function
  98  *
  99  * Loads an icon asynchronously. To finish this function, see
 100  * g_loadable_icon_load_finish(). For the synchronous, blocking
 101  * version of this function, see g_loadable_icon_load().
 102  **/
 103 void
 104 g_loadable_icon_load_async (GLoadableIcon       *icon,
 105                             int                  size,
 106                             GCancellable        *cancellable,
 107                             GAsyncReadyCallback  callback,
 108                             gpointer             user_data)
 109 {
 110   GLoadableIconIface *iface;
 111
 112   g_return_if_fail (G_IS_LOADABLE_ICON (icon));
 113
 114   iface = G_LOADABLE_ICON_GET_IFACE (icon);
 115
 116   (* iface->load_async) (icon, size, cancellable, callback, user_data);
 117 }
 118
 119 /**
 120  * g_loadable_icon_load_finish:
 121  * @icon: a #GLoadableIcon.
 122  * @res: a #GAsyncResult.
 123  * @type: (out) (allow-none): a location to store the type of the
 124  *        loaded icon, %NULL to ignore.
 125  * @error: a #GError location to store the error occurring, or %NULL to
 126  * ignore.
 127  *
 128  * Finishes an asynchronous icon load started in g_loadable_icon_load_async().
 129  *
 130  * Returns: (transfer full): a #GInputStream to read the icon from.
 131  **/
 132 GInputStream *
 133 g_loadable_icon_load_finish (GLoadableIcon  *icon,
 134                              GAsyncResult   *res,
 135                              char          **type,
 136                              GError        **error)
 137 {
 138   GLoadableIconIface *iface;
 139
 140   g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
 141   g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
 142
 143   if (g_async_result_legacy_propagate_error (res, error))
 144     return NULL;
 145
 146   iface = G_LOADABLE_ICON_GET_IFACE (icon);
 147
 148   return (* iface->load_finish) (icon, res, type, error);
 149 }
 150
 151 /********************************************
 152  *   Default implementation of async load   *
 153  ********************************************/
 154
 155 typedef struct {
 156   int size;
 157   char *type;
 158 } LoadData;
 159
 160 static void
 161 load_data_free (LoadData *data)
 162 {
 163   g_free (data->type);
 164   g_free (data);
 165 }
 166
 167 static void
 168 load_async_thread (GTask        *task,
 169                    gpointer      source_object,
 170                    gpointer      task_data,
 171                    GCancellable *cancellable)
 172 {
 173   GLoadableIcon *icon = source_object;
 174   LoadData *data = task_data;
 175   GLoadableIconIface *iface;
 176   GInputStream *stream;
 177   GError *error = NULL;
 178
 179   iface = G_LOADABLE_ICON_GET_IFACE (icon);
 180   stream = iface->load (icon, data->size, &data->type,
 181                         cancellable, &error);
 182
 183   if (stream)
 184     g_task_return_pointer (task, stream, g_object_unref);
 185   else
 186     g_task_return_error (task, error);
 187 }
 188
 189
 190
 191 static void
 192 g_loadable_icon_real_load_async (GLoadableIcon       *icon,
 193                                  int                  size,
 194                                  GCancellable        *cancellable,
 195                                  GAsyncReadyCallback  callback,
 196                                  gpointer             user_data)
 197 {
 198   GTask *task;
 199   LoadData *data;
 200
 201   task = g_task_new (icon, cancellable, callback, user_data);
 202   data = g_new0 (LoadData, 1);
 203   g_task_set_task_data (task, data, (GDestroyNotify) load_data_free);
 204   g_task_run_in_thread (task, load_async_thread);
 205   g_object_unref (task);
 206 }
 207
 208 static GInputStream *
 209 g_loadable_icon_real_load_finish (GLoadableIcon        *icon,
 210                                   GAsyncResult         *res,
 211                                   char                **type,
 212                                   GError              **error)
 213 {
 214   GTask *task;
 215   LoadData *data;
 216   GInputStream *stream;
 217
 218   g_return_val_if_fail (g_task_is_valid (res, icon), NULL);
 219
 220   task = G_TASK (res);
 221   data = g_task_get_task_data (task);
 222
 223   stream = g_task_propagate_pointer (task, error);
 224   if (stream && type)
 225     {
 226       *type = data->type;
 227       data->type = NULL;
 228     }
 229
 230   return stream;
 231 }