git.sesse.net Git - vlc/blob - 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     int canc = vlc_savecancel();
 170 #ifdef HAVE_DBUS
 171     p_intf->p_sys->p_connection = dbus_init( p_intf );
 172 #endif
 173
 174     for( ;; )
 175    {
 176         vlc_object_t *p_vout;
 177
 178         p_vout = vlc_object_find( p_intf, VLC_OBJECT_VOUT, FIND_ANYWHERE );
 179
 180         /* If there is a video output, disable xscreensaver */
 181         if( p_vout )
 182         {
 183             input_thread_t *p_input;
 184             p_input = vlc_object_find( p_vout, VLC_OBJECT_INPUT, FIND_PARENT );
 185             vlc_object_release( p_vout );
 186             if( p_input )
 187             {
 188                 if( PLAYING_S == p_input->i_state )
 189                 {
 190                     /* http://www.jwz.org/xscreensaver/faq.html#dvd */
 191                     const char *const ppsz_xsargs[] = { "/bin/sh", "-c",
 192                             "xscreensaver-command -deactivate &", (char*)NULL };
 193                     Execute( p_intf, ppsz_xsargs );
 194
 195                     /* If we have dbus support, let's communicate directly
 196                        with gnome-screensave else, run
 197                        gnome-screensaver-command */
 198 #ifdef HAVE_DBUS
 199                     poke_screensaver( p_intf, p_intf->p_sys->p_connection );
 200 #else
 201                     const char *const ppsz_gsargs[] = { "/bin/sh", "-c",
 202                             "gnome-screensaver-command --poke &", (char*)NULL };
 203                     Execute( p_intf, ppsz_gsargs );
 204 #endif
 205                     /* FIXME: add support for other screensavers */
 206                 }
 207                 vlc_object_release( p_input );
 208             }
 209         }
 210
 211         vlc_restorecancel( canc );
 212         /* Check screensaver every 30 seconds */
 213         msleep( 30 * CLOCK_FREQ );
 214     }
 215 }
 216
 217 #ifdef HAVE_DBUS
 218
 219 static DBusConnection * dbus_init( intf_thread_t *p_intf )
 220 {
 221     DBusError dbus_error;
 222
 223     dbus_error_init (&dbus_error);
 224     DBusConnection * p_connection = dbus_bus_get( DBUS_BUS_SESSION, &dbus_error );
 225
 226     if ( !p_connection )
 227     {
 228         msg_Warn( p_intf, "failed to connect to the D-BUS daemon: %s",
 229                           dbus_error.message);
 230         dbus_error_free( &dbus_error );
 231         return NULL;
 232     }
 233
 234     return p_connection;
 235 }
 236
 237 static void poke_screensaver( intf_thread_t *p_intf,
 238                               DBusConnection *p_connection )
 239 {
 240     if( screensaver_is_running( p_connection ) )
 241     {
 242 #   ifdef SCREENSAVER_DEBUG
 243         msg_Dbg( p_intf, "found a running gnome-screensaver instance" );
 244 #   endif
 245         /* gnome-screensaver changed it's D-Bus interface, so we need both */
 246         screensaver_send_message_void( p_intf, p_connection, "Poke" );
 247         screensaver_send_message_void( p_intf, p_connection,
 248                 "SimulateUserActivity" );
 249     }
 250 #   ifdef SCREENSAVER_DEBUG
 251     else
 252     {
 253         msg_Dbg( p_intf, "found no running gnome-screensaver instance" );
 254     }
 255 #   endif
 256 }
 257
 258 static void screensaver_send_message_void ( intf_thread_t *p_intf,
 259                                        DBusConnection *p_connection,
 260                                        const char *psz_name )
 261 {
 262     DBusMessage *p_message;
 263
 264     if( !p_connection || !psz_name ) return;
 265
 266     p_message = dbus_message_new_method_call( GS_SERVICE, GS_PATH,
 267                                               GS_INTERFACE, psz_name );
 268     if( p_message == NULL )
 269     {
 270         msg_Err( p_intf, "DBUS initialization failed: message initialization" );
 271         return;
 272     }
 273
 274     if( !dbus_connection_send( p_connection, p_message, NULL ) )
 275     {
 276         msg_Err( p_intf, "DBUS communication failed" );
 277     }
 278
 279     dbus_connection_flush( p_connection );
 280
 281     dbus_message_unref( p_message );
 282 }
 283
 284 static bool screensaver_is_running( DBusConnection *p_connection )
 285 {
 286     DBusError error;
 287     bool b_return;
 288
 289     if( !p_connection ) return false;
 290
 291     dbus_error_init( &error );
 292     b_return = dbus_bus_name_has_owner( p_connection, GS_SERVICE, &error );
 293     if( dbus_error_is_set( &error ) ) dbus_error_free (&error);
 294
 295     return b_return;
 296 }
 297
 298 #endif
 299