bin/vlc.c

   1 /*****************************************************************************
   2  * vlc.c: the VLC player
   3  *****************************************************************************
   4  * Copyright (C) 1998-2008 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Vincent Seguin <seguin@via.ecp.fr>
   8  *          Samuel Hocevar <sam@zoy.org>
   9  *          Gildas Bazin <gbazin@videolan.org>
  10  *          Derk-Jan Hartman <hartman at videolan dot org>
  11  *          Lots of other people, see the libvlc AUTHORS file
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc/vlc.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <stdbool.h>
  36 #include <string.h>
  37 #include <locale.h>
  38 #include <signal.h>
  39 #ifdef HAVE_PTHREAD_H
  40 # include <pthread.h>
  41 #endif
  42 #include <unistd.h>
  43
  44 #ifdef __OS2__
  45 # define pthread_t      int
  46 # define pthread_self() _gettid()
  47 #endif
  48
  49
  50 extern void vlc_enable_override (void);
  51
  52 static bool signal_ignored (int signum)
  53 {
  54     struct sigaction sa;
  55
  56     if (sigaction (signum, NULL, &sa))
  57         return false;
  58     return ((sa.sa_flags & SA_SIGINFO)
  59             ? (void *)sa.sa_sigaction : (void *)sa.sa_handler) == SIG_IGN;
  60 }
  61
  62 static void vlc_kill (void *data)
  63 {
  64 #ifndef __OS2__
  65     pthread_t *ps = data;
  66
  67     pthread_kill (*ps, SIGTERM);
  68 #else
  69     // send a signal to the main thread
  70     kill (getpid(), SIGTERM);
  71 #endif
  72 }
  73
  74 static void exit_timeout (int signum)
  75 {
  76     (void) signum;
  77     signal (SIGINT, SIG_DFL);
  78 }
  79
  80 /*****************************************************************************
  81  * main: parse command line, start interface and spawn threads.
  82  *****************************************************************************/
  83 int main( int i_argc, const char *ppsz_argv[] )
  84 {
  85     /* The so-called POSIX-compliant MacOS X reportedly processes SIGPIPE even
  86      * if it is blocked in all thread.
  87      * Note: this is NOT an excuse for not protecting against SIGPIPE. If
  88      * LibVLC runs outside of VLC, we cannot rely on this code snippet. */
  89     signal (SIGPIPE, SIG_IGN);
  90     /* Restore SIGCHLD in case our parent process ignores it. */
  91     signal (SIGCHLD, SIG_DFL);
  92
  93 #ifndef NDEBUG
  94     /* Activate malloc checking routines to detect heap corruptions. */
  95     setenv ("MALLOC_CHECK_", "2", 1);
  96
  97     /* Disable the ugly Gnome crash dialog so that we properly segfault */
  98     setenv ("GNOME_DISABLE_CRASH_DIALOG", "1", 1);
  99 #endif
 100
 101 #ifdef TOP_BUILDDIR
 102     setenv ("VLC_PLUGIN_PATH", TOP_BUILDDIR"/modules", 1);
 103     setenv ("VLC_DATA_PATH", TOP_SRCDIR"/share", 1);
 104 #endif
 105
 106     /* Clear the X.Org startup notification ID. Otherwise the UI might try to
 107      * change the environment while the process is multi-threaded. That could
 108      * crash. Screw you X.Org. Next time write a thread-safe specification. */
 109     unsetenv ("DESKTOP_STARTUP_ID");
 110
 111 #ifndef ALLOW_RUN_AS_ROOT
 112     if (geteuid () == 0)
 113     {
 114         fprintf (stderr, "VLC is not supposed to be run as root. Sorry.\n"
 115         "If you need to use real-time priorities and/or privileged TCP ports\n"
 116         "you can use %s-wrapper (make sure it is Set-UID root and\n"
 117         "cannot be run by non-trusted users first).\n", ppsz_argv[0]);
 118         return 1;
 119     }
 120 #endif
 121
 122     setlocale (LC_ALL, "");
 123
 124     if (isatty (STDERR_FILENO))
 125         /* This message clutters error logs. It is printed only on a TTY.
 126          * Fortunately, LibVLC prints version info with -vv anyway. */
 127         fprintf (stderr, "VLC media player %s (revision %s)\n",
 128                  libvlc_get_version(), libvlc_get_changeset());
 129
 130     sigset_t set;
 131
 132     sigemptyset (&set);
 133     /* VLC uses sigwait() to dequeue interesting signals.
 134      * For this to work, those signals must be blocked in all threads,
 135      * including the thread calling sigwait() (see the man page for details).
 136      *
 137      * There are two advantages to sigwait() over traditional signal handlers:
 138      *  - delivery is synchronous: no need to worry about async-safety,
 139      *  - EINTR is not generated: other threads need not handle that error.
 140      * That being said, some LibVLC programs do not use sigwait(). Therefore
 141      * EINTR must still be handled cleanly, notably from poll() calls.
 142      *
 143      * Signals that request a clean shutdown, and force an unclean shutdown
 144      * if they are triggered again 2+ seconds later.
 145      * We have to handle SIGTERM cleanly because of daemon mode. */
 146     sigaddset (&set, SIGINT);
 147     sigaddset (&set, SIGHUP);
 148     sigaddset (&set, SIGQUIT);
 149     sigaddset (&set, SIGTERM);
 150
 151     /* SIGPIPE can happen and would crash the process. On modern systems,
 152      * the MSG_NOSIGNAL flag protects socket write operations against SIGPIPE.
 153      * But we still need to block SIGPIPE when:
 154      *  - writing to pipes,
 155      *  - using write() instead of send() for code not specific to sockets.
 156      * LibVLC code assumes that SIGPIPE is blocked. Other LibVLC applications
 157      * shall block it (or handle it somehow) too.
 158      */
 159     sigaddset (&set, SIGPIPE);
 160
 161     /* SIGCHLD must be dequeued to clean up zombie child processes.
 162      * Furthermore the handler must not be set to SIG_IGN (see above).
 163      * We cannot pragmatically handle EINTR, short reads and short writes
 164      * in every code paths (including underlying libraries). So we just
 165      * block SIGCHLD in all threads, and dequeue it below. */
 166     sigaddset (&set, SIGCHLD);
 167
 168     /* Block all these signals */
 169     pthread_sigmask (SIG_SETMASK, &set, NULL);
 170
 171     const char *argv[i_argc + 2];
 172     int argc = 0;
 173
 174     argv[argc++] = "--no-ignore-config";
 175     argv[argc++] = "--media-library";
 176     ppsz_argv++; i_argc--; /* skip executable path */
 177 #ifdef __APPLE__
 178     /* When VLC.app is run by double clicking in Mac OS X, the 2nd arg
 179      * is the PSN - process serial number (a unique PID-ish thingie)
 180      * still ok for real Darwin & when run from command line
 181      * for example -psn_0_9306113 */
 182     if (i_argc >= 1 && !strncmp (*ppsz_argv, "-psn" , 4))
 183         ppsz_argv++, i_argc--;
 184 #endif
 185     memcpy (argv + argc, ppsz_argv, i_argc * sizeof (*argv));
 186     argc += i_argc;
 187     argv[argc] = NULL;
 188
 189     vlc_enable_override ();
 190
 191     /* Initialize libvlc */
 192     libvlc_instance_t *vlc = libvlc_new (argc, argv);
 193     if (vlc == NULL)
 194         goto out;
 195
 196     libvlc_set_user_agent (vlc, "VLC media player", "VLC/"PACKAGE_VERSION);
 197
 198 #if !defined (HAVE_MAEMO) && !defined __APPLE__ && !defined (__OS2__)
 199     libvlc_add_intf (vlc, "globalhotkeys,none");
 200 #endif
 201 #ifdef HAVE_DBUS
 202     libvlc_add_intf (vlc, "dbus,none");
 203     libvlc_add_intf (vlc, "inhibit,none");
 204 #endif
 205     if (libvlc_add_intf (vlc, NULL))
 206         goto out;
 207
 208     libvlc_playlist_play (vlc, -1, 0, NULL);
 209
 210     /* Wait for a termination signal */
 211     pthread_t self = pthread_self ();
 212     libvlc_set_exit_handler (vlc, vlc_kill, &self);
 213
 214     /* Qt4 insists on catching SIGCHLD via signal handler. To work around that,
 215      * unblock it after all our child threads are created. */
 216     sigdelset (&set, SIGCHLD);
 217     pthread_sigmask (SIG_SETMASK, &set, NULL);
 218
 219     /* Do not dequeue SIGHUP if it is ignored (nohup) */
 220     if (signal_ignored (SIGHUP))
 221         sigdelset (&set, SIGHUP);
 222     /* Ignore SIGPIPE */
 223     sigdelset (&set, SIGPIPE);
 224
 225     int signum;
 226     sigwait (&set, &signum);
 227
 228     /* Restore default signal behaviour after 3 seconds */
 229     sigemptyset (&set);
 230     sigaddset (&set, SIGINT);
 231     sigaddset (&set, SIGALRM);
 232     signal (SIGINT, SIG_IGN);
 233     signal (SIGALRM, exit_timeout);
 234     pthread_sigmask (SIG_UNBLOCK, &set, NULL);
 235     alarm (3);
 236
 237     /* Cleanup */
 238 out:
 239     if (vlc != NULL)
 240         libvlc_release (vlc);
 241
 242     return 0;
 243 }