mutter/src/core/meta-sound-player.c
Andrea Azzarone 8856a396fd sound-player: Don't deadlock in finish_cb
The function finish_cb can be called as a result of a call to ca_context_cancel
in cancelled_cb. This will result in a deadlock because, as per documentation,
g_cancellable_disconnect cannot be called inside the cancellable handler.

It is possible to detect if the call to finish_cb is caused by ca_context_cancel
checking if error_code == CA_ERROR_CANCELED. To avoid the deadlock we should
call g_signal_handler_disconnect instead g_cancellable_disconnect if this is the
case.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/474
2019-03-05 12:07:41 +00:00

295 lines
7.9 KiB
C

/*
* Copyright (C) 2018 Red Hat
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
* 02111-1307, USA.
*
* Author: Carlos Garnacho <carlosg@gnome.org>
*/
#include "config.h"
#include <canberra.h>
#include "meta/meta-sound-player.h"
#define EVENT_SOUNDS_KEY "event-sounds"
#define THEME_NAME_KEY "theme-name"
typedef struct _MetaPlayRequest MetaPlayRequest;
struct _MetaSoundPlayer
{
GObject parent;
GThreadPool *queue;
GSettings *settings;
ca_context *context;
uint32_t id_pool;
};
struct _MetaPlayRequest
{
ca_proplist *props;
uint32_t id;
guint cancel_id;
GCancellable *cancellable;
MetaSoundPlayer *player;
};
const char * const cache_whitelist[] = {
"bell-window-system",
"desktop-switch-left",
"desktop-switch-right",
"desktop-switch-up",
"desktop-switch-down",
NULL
};
G_DEFINE_TYPE (MetaSoundPlayer, meta_sound_player, G_TYPE_OBJECT)
static MetaPlayRequest *
meta_play_request_new (MetaSoundPlayer *player,
ca_proplist *props,
GCancellable *cancellable)
{
MetaPlayRequest *req;
req = g_new0 (MetaPlayRequest, 1);
req->props = props;
req->player = player;
g_set_object (&req->cancellable, cancellable);
return req;
}
static void
meta_play_request_free (MetaPlayRequest *req)
{
g_clear_object (&req->cancellable);
ca_proplist_destroy (req->props);
g_free (req);
}
static void
meta_sound_player_finalize (GObject *object)
{
MetaSoundPlayer *player = META_SOUND_PLAYER (object);
g_object_unref (player->settings);
g_thread_pool_free (player->queue, FALSE, TRUE);
ca_context_destroy (player->context);
G_OBJECT_CLASS (meta_sound_player_parent_class)->finalize (object);
}
static void
meta_sound_player_class_init (MetaSoundPlayerClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = meta_sound_player_finalize;
}
static void
cancelled_cb (GCancellable *cancellable,
MetaPlayRequest *req)
{
ca_context_cancel (req->player->context, req->id);
}
static void
finish_cb (ca_context *context,
uint32_t id,
int error_code,
gpointer user_data)
{
MetaPlayRequest *req = user_data;
if (error_code != CA_ERROR_CANCELED)
g_cancellable_disconnect (req->cancellable, req->cancel_id);
else if (req->cancellable != NULL && req->cancel_id != 0)
g_signal_handler_disconnect (req->cancellable, req->cancel_id);
meta_play_request_free (req);
}
static void
play_sound (MetaPlayRequest *req,
MetaSoundPlayer *player)
{
req->id = player->id_pool++;
if (ca_context_play_full (player->context, req->id, req->props,
finish_cb, req) != CA_SUCCESS)
{
meta_play_request_free (req);
return;
}
if (req->cancellable)
{
req->cancel_id =
g_cancellable_connect (req->cancellable,
G_CALLBACK (cancelled_cb), req, NULL);
}
}
static void
settings_changed_cb (GSettings *settings,
const char *key,
MetaSoundPlayer *player)
{
if (strcmp (key, EVENT_SOUNDS_KEY) == 0)
{
gboolean enabled;
enabled = g_settings_get_boolean (settings, EVENT_SOUNDS_KEY);
ca_context_change_props (player->context, CA_PROP_CANBERRA_ENABLE,
enabled ? "1" : "0", NULL);
}
else if (strcmp (key, THEME_NAME_KEY) == 0)
{
char *theme_name;
theme_name = g_settings_get_string (settings, THEME_NAME_KEY);
ca_context_change_props (player->context, CA_PROP_CANBERRA_XDG_THEME_NAME,
theme_name, NULL);
g_free (theme_name);
}
}
static ca_context *
create_context (GSettings *settings)
{
ca_context *context;
ca_proplist *props;
gboolean enabled;
char *theme_name;
if (ca_context_create (&context) != CA_SUCCESS)
return NULL;
if (ca_proplist_create (&props) != CA_SUCCESS)
{
ca_context_destroy (context);
return NULL;
}
ca_proplist_sets (props, CA_PROP_APPLICATION_NAME, "Mutter");
enabled = g_settings_get_boolean (settings, EVENT_SOUNDS_KEY);
ca_proplist_sets (props, CA_PROP_CANBERRA_ENABLE, enabled ? "1" : "0");
theme_name = g_settings_get_string (settings, THEME_NAME_KEY);
ca_proplist_sets (props, CA_PROP_CANBERRA_XDG_THEME_NAME, theme_name);
g_free (theme_name);
ca_context_change_props_full (context, props);
ca_proplist_destroy (props);
return context;
}
static void
meta_sound_player_init (MetaSoundPlayer *player)
{
player->queue = g_thread_pool_new ((GFunc) play_sound,
player, 1, FALSE, NULL);
player->settings = g_settings_new ("org.gnome.desktop.sound");
player->context = create_context (player->settings);
g_signal_connect (player->settings, "changed",
G_CALLBACK (settings_changed_cb), player);
}
static void
build_ca_proplist (ca_proplist *props,
const char *event_property,
const char *event_id,
const char *event_description)
{
ca_proplist_sets (props, event_property, event_id);
ca_proplist_sets (props, CA_PROP_EVENT_DESCRIPTION, event_description);
}
/**
* meta_sound_player_play_from_theme:
* @player: a #MetaSoundPlayer
* @name: sound theme name of the event
* @description: description of the event
* @cancellable: cancellable for the request
*
* Plays a sound from the sound theme.
**/
void
meta_sound_player_play_from_theme (MetaSoundPlayer *player,
const char *name,
const char *description,
GCancellable *cancellable)
{
MetaPlayRequest *req;
ca_proplist *props;
g_return_if_fail (META_IS_SOUND_PLAYER (player));
g_return_if_fail (name != NULL);
g_return_if_fail (!cancellable || G_IS_CANCELLABLE (cancellable));
ca_proplist_create (&props);
build_ca_proplist (props, CA_PROP_EVENT_ID, name, description);
if (g_strv_contains (cache_whitelist, name))
ca_proplist_sets (props, CA_PROP_CANBERRA_CACHE_CONTROL, "permanent");
else
ca_proplist_sets (props, CA_PROP_CANBERRA_CACHE_CONTROL, "volatile");
req = meta_play_request_new (player, props, cancellable);
g_thread_pool_push (player->queue, req, NULL);
}
/**
* meta_sound_player_play_from_file:
* @player: a #MetaSoundPlayer
* @file: file to play
* @description: description of the played sound
* @cancellable: cancellable for the request
*
* Plays a sound from a file.
**/
void
meta_sound_player_play_from_file (MetaSoundPlayer *player,
GFile *file,
const char *description,
GCancellable *cancellable)
{
MetaPlayRequest *req;
ca_proplist *props;
char *path;
g_return_if_fail (META_IS_SOUND_PLAYER (player));
g_return_if_fail (G_IS_FILE (file));
g_return_if_fail (!cancellable || G_IS_CANCELLABLE (cancellable));
path = g_file_get_path (file);
g_return_if_fail (path != NULL);
ca_proplist_create (&props);
build_ca_proplist (props, CA_PROP_MEDIA_FILENAME, path, description);
ca_proplist_sets (props, CA_PROP_CANBERRA_CACHE_CONTROL, "volatile");
g_free (path);
req = meta_play_request_new (player, props, cancellable);
g_thread_pool_push (player->queue, req, NULL);
}