src/misc/exit.c

   1 /*****************************************************************************
   2  * exit.c: LibVLC termination event
   3  *****************************************************************************
   4  * Copyright (C) 2009-2010 VLC authors and VideoLAN
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <vlc_common.h>
  26 #include <vlc_interface.h>
  27 #include "libvlc.h"
  28 #include "../lib/libvlc_internal.h"
  29
  30 void vlc_ExitInit( vlc_exit_t *exit )
  31 {
  32     vlc_mutex_init( &exit->lock );
  33     exit->handler = NULL;
  34     exit->opaque = NULL;
  35     exit->killed = false;
  36 }
  37
  38 void vlc_ExitDestroy( vlc_exit_t *exit )
  39 {
  40     vlc_mutex_destroy( &exit->lock );
  41 }
  42
  43
  44 /**
  45  * Registers a callback for the LibVLC exit event.
  46  *
  47  * @note This function conflicts with libvlc_InternalWait().
  48  * Use either or none of them, but not both.
  49  */
  50 void libvlc_SetExitHandler( libvlc_int_t *p_libvlc, void (*handler) (void *),
  51                             void *opaque )
  52 {
  53     vlc_exit_t *exit = &libvlc_priv( p_libvlc )->exit;
  54
  55     vlc_mutex_lock( &exit->lock );
  56     if( exit->killed ) /* already exited! (race condition) */
  57         handler( opaque );
  58     exit->handler = handler;
  59     exit->opaque = opaque;
  60     vlc_mutex_unlock( &exit->lock );
  61 }
  62
  63 /**
  64  * Posts an exit signal to LibVLC instance. This only emits a notification to
  65  * the main thread. It might take a while before the actual cleanup occurs.
  66  * This function should only be called on behalf of the user.
  67  */
  68 void libvlc_Quit( libvlc_int_t *p_libvlc )
  69 {
  70     vlc_exit_t *exit = &libvlc_priv( p_libvlc )->exit;
  71
  72     vlc_mutex_lock( &exit->lock );
  73     if( !exit->killed )
  74     {
  75         msg_Dbg( p_libvlc, "exiting" );
  76         exit->killed = true;
  77         if( exit->handler != NULL )
  78             exit->handler( exit->opaque );
  79     }
  80     vlc_mutex_unlock( &exit->lock );
  81 }
  82
  83
  84 static void exit_wakeup( void *data )
  85 {
  86     vlc_cond_signal( data );
  87 }
  88
  89 /**
  90  * Waits until the LibVLC instance gets an exit signal.
  91  * This normally occurs when the user "exits" an interface plugin. But it can
  92  * also be triggered by the special vlc://quit item, the update checker, or
  93  * the playlist engine.
  94  */
  95 void libvlc_InternalWait( libvlc_int_t *p_libvlc )
  96 {
  97     vlc_exit_t *exit = &libvlc_priv( p_libvlc )->exit;
  98     vlc_cond_t wait;
  99
 100     vlc_cond_init( &wait );
 101
 102     vlc_mutex_lock( &exit->lock );
 103     exit->handler = exit_wakeup;
 104     exit->opaque = &wait;
 105     while( !exit->killed )
 106         vlc_cond_wait( &wait, &exit->lock );
 107     vlc_mutex_unlock( &exit->lock );
 108
 109     vlc_cond_destroy( &wait );
 110 }