]> git.sesse.net Git - vlc/blob - modules/misc/screensaver.c
Fix compiler warning about asprintf return value.
[vlc] / modules / misc / screensaver.c
1 /*****************************************************************************
2  * screensaver.c : disable screen savers when VLC is playing
3  *****************************************************************************
4  * Copyright (C) 2006 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Sam Hocevar <sam@zoy.org>
8  *          Benjamin Pracht <bigben AT videolan DOT org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23  *****************************************************************************/
24
25 /*****************************************************************************
26  * Preamble
27  *****************************************************************************/
28
29 #ifdef HAVE_CONFIG_H
30 # include "config.h"
31 #endif
32
33 #include <vlc_common.h>
34 #include <vlc_plugin.h>
35 #include <vlc_input.h>
36 #include <vlc_interface.h>
37 #include <vlc_aout.h>
38 #include <vlc_vout.h>
39
40 #include <sys/types.h>
41 #include <sys/wait.h>
42 #include <unistd.h>
43
44 #ifdef HAVE_SIGNAL_H
45 #   include <signal.h>
46 #endif
47
48 #ifdef HAVE_DBUS
49
50 #include <dbus/dbus.h>
51
52 #define GS_SERVICE   "org.gnome.ScreenSaver"
53 #define GS_PATH      "/org/gnome/ScreenSaver"
54 #define GS_INTERFACE "org.gnome.ScreenSaver"
55
56 #endif
57
58 /*****************************************************************************
59  * Local prototypes
60  *****************************************************************************/
61 static int  Activate     ( vlc_object_t * );
62 static void  Deactivate   ( vlc_object_t * );
63
64 static void Run          ( intf_thread_t *p_intf );
65
66 #ifdef HAVE_DBUS
67
68 static DBusConnection * dbus_init( intf_thread_t *p_intf );
69 static void poke_screensaver( intf_thread_t *p_intf,
70                               DBusConnection *p_connection );
71 static void screensaver_send_message_void ( intf_thread_t *p_intf,
72                                        DBusConnection *p_connection,
73                                        const char *psz_name );
74 static bool screensaver_is_running( DBusConnection *p_connection );
75
76
77 struct intf_sys_t
78 {
79     DBusConnection *p_connection;
80 };
81
82 #endif
83
84 /*****************************************************************************
85  * Module descriptor
86  *****************************************************************************/
87 vlc_module_begin();
88     set_description( N_("X Screensaver disabler") );
89     set_capability( "interface", 0 );
90     set_callbacks( Activate, Deactivate );
91 vlc_module_end();
92
93 /*****************************************************************************
94  * Activate: initialize and create stuff
95  *****************************************************************************/
96 static int Activate( vlc_object_t *p_this )
97 {
98     intf_thread_t *p_intf = (intf_thread_t*)p_this;
99
100     p_intf->pf_run = Run;
101
102 #ifdef HAVE_DBUS
103     p_intf->p_sys = (intf_sys_t *)malloc( sizeof( intf_sys_t ) );
104     if( !p_intf->p_sys ) return VLC_ENOMEM;
105 #endif
106
107     return VLC_SUCCESS;
108 }
109
110 /*****************************************************************************
111  * Deactivate: uninitialize and cleanup
112  *****************************************************************************/
113 static void Deactivate( vlc_object_t *p_this )
114 {
115 #ifdef HAVE_DBUS
116     intf_thread_t *p_intf = (intf_thread_t*)p_this;
117
118     if( p_intf->p_sys->p_connection )
119     {
120         dbus_connection_unref( p_intf->p_sys->p_connection );
121     }
122
123     free( p_intf->p_sys );
124     p_intf->p_sys = NULL;
125 #endif
126 }
127
128 /*****************************************************************************
129  * Execute: Spawns a process using execv()
130  *****************************************************************************/
131 static void Execute( intf_thread_t *p_this, const char *const *ppsz_args )
132 {
133     pid_t pid = fork();
134     switch( pid )
135     {
136         case 0:     /* we're the child */
137         {
138             sigset_t set;
139             sigemptyset (&set);
140             pthread_sigmask (SIG_SETMASK, &set, NULL);
141
142             /* We don't want output */
143             if( ( freopen( "/dev/null", "w", stdout ) != NULL )
144              && ( freopen( "/dev/null", "w", stderr ) != NULL ) )
145                 execv( ppsz_args[0] , (char *const *)ppsz_args );
146             /* If the file we want to execute doesn't exist we exit() */
147             exit( EXIT_FAILURE );
148         }
149         case -1:    /* we're the error */
150             msg_Dbg( p_this, "Couldn't fork() while launching %s",
151                      ppsz_args[0] );
152             break;
153         default:    /* we're the parent */
154             /* Wait for the child to exit.
155              * We will not deadlock because we ran "/bin/sh &" */
156             while( waitpid( pid, NULL, 0 ) != pid);
157             break;
158     }
159 }
160
161 /*****************************************************************************
162  * Run: main thread
163  *****************************************************************************
164  * This part of the module is in a separate thread so that we do not have
165  * too much system() overhead.
166  *****************************************************************************/
167 static void Run( intf_thread_t *p_intf )
168 {
169     mtime_t deadline = mdate();
170
171     vlc_object_lock( p_intf );
172 #ifdef HAVE_DBUS
173     p_intf->p_sys->p_connection = dbus_init( p_intf );
174 #endif
175
176     while( vlc_object_alive( p_intf ) )
177     {
178         vlc_object_t *p_vout;
179
180         if( vlc_object_timedwait( p_intf, deadline ) == 0 )
181             continue;
182
183         p_vout = vlc_object_find( p_intf, VLC_OBJECT_VOUT, FIND_ANYWHERE );
184
185         /* If there is a video output, disable xscreensaver */
186         if( p_vout )
187         {
188             input_thread_t *p_input;
189             p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT, FIND_PARENT );
190             vlc_object_release( p_vout );
191             if( p_input )
192             {
193                 if( PLAYING_S == p_input->i_state )
194                 {
195                     /* http://www.jwz.org/xscreensaver/faq.html#dvd */
196                     const char *const ppsz_xsargs[] = { "/bin/sh", "-c",
197                             "xscreensaver-command -deactivate &", (char*)NULL };
198                     Execute( p_intf, ppsz_xsargs );
199
200                     /* If we have dbus support, let's communicate directly
201                        with gnome-screensave else, run
202                        gnome-screensaver-command */
203 #ifdef HAVE_DBUS
204                     poke_screensaver( p_intf, p_intf->p_sys->p_connection );
205 #else
206                     const char *const ppsz_gsargs[] = { "/bin/sh", "-c",
207                             "gnome-screensaver-command --poke &", (char*)NULL };
208                     Execute( p_intf, ppsz_gsargs );
209 #endif
210                     /* FIXME: add support for other screensavers */
211                 }
212                 vlc_object_release( p_input );
213             }
214         }
215
216         /* Check screensaver every 30 seconds */
217         deadline = mdate() + 30000000;
218     }
219     vlc_object_unlock( p_intf );
220 }
221
222 #ifdef HAVE_DBUS
223
224 static DBusConnection * dbus_init( intf_thread_t *p_intf )
225 {
226     DBusError dbus_error;
227
228     dbus_error_init (&dbus_error);
229     DBusConnection * p_connection = dbus_bus_get( DBUS_BUS_SESSION, &dbus_error );
230
231     if ( !p_connection )
232     {
233         msg_Warn( p_intf, "failed to connect to the D-BUS daemon: %s",
234                           dbus_error.message);
235         dbus_error_free( &dbus_error );
236         return NULL;
237     }
238
239     return p_connection;
240 }
241
242 static void poke_screensaver( intf_thread_t *p_intf,
243                               DBusConnection *p_connection )
244 {
245     if( screensaver_is_running( p_connection ) )
246     {
247 #   ifdef SCREENSAVER_DEBUG
248         msg_Dbg( p_intf, "found a running gnome-screensaver instance" );
249 #   endif
250         /* gnome-screensaver changed it's D-Bus interface, so we need both */
251         screensaver_send_message_void( p_intf, p_connection, "Poke" );
252         screensaver_send_message_void( p_intf, p_connection,
253                 "SimulateUserActivity" );
254     }
255 #   ifdef SCREENSAVER_DEBUG
256     else
257     {
258         msg_Dbg( p_intf, "found no running gnome-screensaver instance" );
259     }
260 #   endif
261 }
262
263 static void screensaver_send_message_void ( intf_thread_t *p_intf,
264                                        DBusConnection *p_connection,
265                                        const char *psz_name )
266 {
267     DBusMessage *p_message;
268
269     if( !p_connection || !psz_name ) return;
270
271     p_message = dbus_message_new_method_call( GS_SERVICE, GS_PATH,
272                                               GS_INTERFACE, psz_name );
273     if( p_message == NULL )
274     {
275         msg_Err( p_intf, "DBUS initialization failed: message initialization" );
276         return;
277     }
278
279     if( !dbus_connection_send( p_connection, p_message, NULL ) )
280     {
281         msg_Err( p_intf, "DBUS communication failed" );
282     }
283
284     dbus_connection_flush( p_connection );
285
286     dbus_message_unref( p_message );
287 }
288
289 static bool screensaver_is_running( DBusConnection *p_connection )
290 {
291     DBusError error;
292     bool b_return;
293
294     if( !p_connection ) return false;
295
296     dbus_error_init( &error );
297     b_return = dbus_bus_name_has_owner( p_connection, GS_SERVICE, &error );
298     if( dbus_error_is_set( &error ) ) dbus_error_free (&error);
299
300     return b_return;
301 }
302
303 #endif
304