glib/gio/gloadableicon.c
Dan Winship 538b2f106d gio: handle GSimpleAsyncResult errors in _finish vmethods
Originally, the standard idiom with GSimpleAsyncResult was to handle
all errors in the _finish wrapper function, so that vmethods only had
to deal with successful results. But this means that chaining up to a
parent _finish vmethod won't work correctly. Fix this by also checking
for errors in all the relevant vmethods. (We have to redundantly check
in both the vmethod and the wrapper to preserve compatibility.)

https://bugzilla.gnome.org/show_bug.cgi?id=667375
https://bugzilla.gnome.org/show_bug.cgi?id=661767
2012-07-10 10:47:55 -04:00

245 lines
7.0 KiB
C

/* GIO - GLib Input, Output and Streaming Library
*
* Copyright (C) 2006-2007 Red Hat, Inc.
*
* This library 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.
*
* This library 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 this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Alexander Larsson <alexl@redhat.com>
*/
#include "config.h"
#include "gasyncresult.h"
#include "gsimpleasyncresult.h"
#include "gicon.h"
#include "gloadableicon.h"
#include "glibintl.h"
/**
* SECTION:gloadableicon
* @short_description: Loadable Icons
* @include: gio/gio.h
* @see_also: #GIcon, #GThemedIcon
*
* Extends the #GIcon interface and adds the ability to
* load icons from streams.
**/
static void g_loadable_icon_real_load_async (GLoadableIcon *icon,
int size,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data);
static GInputStream *g_loadable_icon_real_load_finish (GLoadableIcon *icon,
GAsyncResult *res,
char **type,
GError **error);
typedef GLoadableIconIface GLoadableIconInterface;
G_DEFINE_INTERFACE(GLoadableIcon, g_loadable_icon, G_TYPE_ICON)
static void
g_loadable_icon_default_init (GLoadableIconIface *iface)
{
iface->load_async = g_loadable_icon_real_load_async;
iface->load_finish = g_loadable_icon_real_load_finish;
}
/**
* g_loadable_icon_load:
* @icon: a #GLoadableIcon.
* @size: an integer.
* @type: (out) (allow-none): a location to store the type of the
* loaded icon, %NULL to ignore.
* @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
* @error: a #GError location to store the error occurring, or %NULL to
* ignore.
*
* Loads a loadable icon. For the asynchronous version of this function,
* see g_loadable_icon_load_async().
*
* Returns: (transfer full): a #GInputStream to read the icon from.
**/
GInputStream *
g_loadable_icon_load (GLoadableIcon *icon,
int size,
char **type,
GCancellable *cancellable,
GError **error)
{
GLoadableIconIface *iface;
g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
iface = G_LOADABLE_ICON_GET_IFACE (icon);
return (* iface->load) (icon, size, type, cancellable, error);
}
/**
* g_loadable_icon_load_async:
* @icon: a #GLoadableIcon.
* @size: an integer.
* @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore.
* @callback: (scope async): a #GAsyncReadyCallback to call when the
* request is satisfied
* @user_data: (closure): the data to pass to callback function
*
* Loads an icon asynchronously. To finish this function, see
* g_loadable_icon_load_finish(). For the synchronous, blocking
* version of this function, see g_loadable_icon_load().
**/
void
g_loadable_icon_load_async (GLoadableIcon *icon,
int size,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GLoadableIconIface *iface;
g_return_if_fail (G_IS_LOADABLE_ICON (icon));
iface = G_LOADABLE_ICON_GET_IFACE (icon);
(* iface->load_async) (icon, size, cancellable, callback, user_data);
}
/**
* g_loadable_icon_load_finish:
* @icon: a #GLoadableIcon.
* @res: a #GAsyncResult.
* @type: a location to store the type of the loaded icon, %NULL to ignore.
* @error: a #GError location to store the error occurring, or %NULL to
* ignore.
*
* Finishes an asynchronous icon load started in g_loadable_icon_load_async().
*
* Returns: (transfer full): a #GInputStream to read the icon from.
**/
GInputStream *
g_loadable_icon_load_finish (GLoadableIcon *icon,
GAsyncResult *res,
char **type,
GError **error)
{
GLoadableIconIface *iface;
g_return_val_if_fail (G_IS_LOADABLE_ICON (icon), NULL);
g_return_val_if_fail (G_IS_ASYNC_RESULT (res), NULL);
if (G_IS_SIMPLE_ASYNC_RESULT (res))
{
GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res);
if (g_simple_async_result_propagate_error (simple, error))
return NULL;
}
iface = G_LOADABLE_ICON_GET_IFACE (icon);
return (* iface->load_finish) (icon, res, type, error);
}
/********************************************
* Default implementation of async load *
********************************************/
typedef struct {
int size;
char *type;
GInputStream *stream;
} LoadData;
static void
load_data_free (LoadData *data)
{
if (data->stream)
g_object_unref (data->stream);
g_free (data->type);
g_free (data);
}
static void
load_async_thread (GSimpleAsyncResult *res,
GObject *object,
GCancellable *cancellable)
{
GLoadableIconIface *iface;
GInputStream *stream;
LoadData *data;
GError *error = NULL;
char *type = NULL;
data = g_simple_async_result_get_op_res_gpointer (res);
iface = G_LOADABLE_ICON_GET_IFACE (object);
stream = iface->load (G_LOADABLE_ICON (object), data->size, &type, cancellable, &error);
if (stream == NULL)
{
g_simple_async_result_take_error (res, error);
}
else
{
data->stream = stream;
data->type = type;
}
}
static void
g_loadable_icon_real_load_async (GLoadableIcon *icon,
int size,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GSimpleAsyncResult *res;
LoadData *data;
res = g_simple_async_result_new (G_OBJECT (icon), callback, user_data, g_loadable_icon_real_load_async);
data = g_new0 (LoadData, 1);
g_simple_async_result_set_op_res_gpointer (res, data, (GDestroyNotify) load_data_free);
g_simple_async_result_run_in_thread (res, load_async_thread, 0, cancellable);
g_object_unref (res);
}
static GInputStream *
g_loadable_icon_real_load_finish (GLoadableIcon *icon,
GAsyncResult *res,
char **type,
GError **error)
{
GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (res);
LoadData *data;
g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == g_loadable_icon_real_load_async);
if (g_simple_async_result_propagate_error (simple, error))
return NULL;
data = g_simple_async_result_get_op_res_gpointer (simple);
if (type)
{
*type = data->type;
data->type = NULL;
}
return g_object_ref (data->stream);
}