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 <locale.h>
  37 #include <signal.h>
  38 #include <pthread.h>
  39 #include <unistd.h>
  40
  41 #ifdef __APPLE__
  42 #include <string.h>
  43 #endif
  44
  45
  46 /* Explicit HACK */
  47 extern void LocaleFree (const char *);
  48 extern char *FromLocale (const char *);
  49 extern void vlc_enable_override (void);
  50
  51 #ifdef HAVE_MAEMO
  52 static void dummy_handler (int signum)
  53 {
  54     (void) signum;
  55 }
  56 #endif
  57
  58 static bool signal_ignored (int signum)
  59 {
  60     struct sigaction sa;
  61
  62     if (sigaction (signum, NULL, &sa))
  63         return false;
  64     return ((sa.sa_flags & SA_SIGINFO)
  65             ? (void *)sa.sa_sigaction : (void *)sa.sa_handler) == SIG_IGN;
  66 }
  67
  68 static void vlc_kill (void *data)
  69 {
  70 #ifndef __OS2__
  71     pthread_t *ps = data;
  72
  73     pthread_kill (*ps, SIGTERM);
  74 #else
  75     // send a signal to the main thread
  76     kill (getpid(), SIGTERM);
  77 #endif
  78 }
  79
  80 static void exit_timeout (int signum)
  81 {
  82     (void) signum;
  83     signal (SIGINT, SIG_DFL);
  84 }
  85
  86 /*****************************************************************************
  87  * main: parse command line, start interface and spawn threads.
  88  *****************************************************************************/
  89 int main( int i_argc, const char *ppsz_argv[] )
  90 {
  91     /* The so-called POSIX-compliant MacOS X reportedly processes SIGPIPE even
  92      * if it is blocked in all thread.
  93      * Note: this is NOT an excuse for not protecting against SIGPIPE. If
  94      * LibVLC runs outside of VLC, we cannot rely on this code snippet. */
  95     signal (SIGPIPE, SIG_IGN);
  96     /* Restore SIGCHLD in case our parent process ignores it. */
  97     signal (SIGCHLD, SIG_DFL);
  98
  99 #ifndef NDEBUG
 100     /* Activate malloc checking routines to detect heap corruptions. */
 101     setenv ("MALLOC_CHECK_", "2", 1);
 102
 103     /* Disable the ugly Gnome crash dialog so that we properly segfault */
 104     setenv ("GNOME_DISABLE_CRASH_DIALOG", "1", 1);
 105 #endif
 106
 107 #ifdef TOP_BUILDDIR
 108     setenv ("VLC_PLUGIN_PATH", TOP_BUILDDIR"/modules", 1);
 109 #endif
 110
 111     /* Clear the X.Org startup notification ID. Otherwise the UI might try to
 112      * change the environment while the process is multi-threaded. That could
 113      * crash. Screw you X.Org. Next time write a thread-safe specification. */
 114     unsetenv ("DESKTOP_STARTUP_ID");
 115
 116 #ifndef ALLOW_RUN_AS_ROOT
 117     if (geteuid () == 0)
 118     {
 119         fprintf (stderr, "VLC is not supposed to be run as root. Sorry.\n"
 120         "If you need to use real-time priorities and/or privileged TCP ports\n"
 121         "you can use %s-wrapper (make sure it is Set-UID root and\n"
 122         "cannot be run by non-trusted users first).\n", ppsz_argv[0]);
 123         return 1;
 124     }
 125 #endif
 126
 127     setlocale (LC_ALL, "");
 128
 129     if (isatty (STDERR_FILENO))
 130         /* This message clutters error logs. It is printed only on a TTY.
 131          * Fortunately, LibVLC prints version info with -vv anyway. */
 132         fprintf (stderr, "VLC media player %s (revision %s)\n",
 133                  libvlc_get_version(), libvlc_get_changeset());
 134
 135     sigset_t set;
 136
 137     sigemptyset (&set);
 138     /* VLC uses sigwait() to dequeue interesting signals.
 139      * For this to work, those signals must be blocked in all threads,
 140      * including the thread calling sigwait() (see the man page for details).
 141      *
 142      * There are two advantages to sigwait() over traditional signal handlers:
 143      *  - delivery is synchronous: no need to worry about async-safety,
 144      *  - EINTR is not generated: other threads need not handle that error.
 145      * That being said, some LibVLC programs do not use sigwait(). Therefore
 146      * EINTR must still be handled cleanly, notably from poll() calls.
 147      *
 148      * Signals that request a clean shutdown, and force an unclean shutdown
 149      * if they are triggered again 2+ seconds later.
 150      * We have to handle SIGTERM cleanly because of daemon mode. */
 151     sigaddset (&set, SIGINT);
 152     sigaddset (&set, SIGHUP);
 153     sigaddset (&set, SIGQUIT);
 154     sigaddset (&set, SIGTERM);
 155
 156     /* SIGPIPE can happen and would crash the process. On modern systems,
 157      * the MSG_NOSIGNAL flag protects socket write operations against SIGPIPE.
 158      * But we still need to block SIGPIPE when:
 159      *  - writing to pipes,
 160      *  - using write() instead of send() for code not specific to sockets.
 161      * LibVLC code assumes that SIGPIPE is blocked. Other LibVLC applications
 162      * shall block it (or handle it somehow) too.
 163      */
 164     sigaddset (&set, SIGPIPE);
 165
 166     /* SIGCHLD must be dequeued to clean up zombie child processes.
 167      * Furthermore the handler must not be set to SIG_IGN (see above).
 168      * We cannot pragmatically handle EINTR, short reads and short writes
 169      * in every code paths (including underlying libraries). So we just
 170      * block SIGCHLD in all threads, and dequeue it below. */
 171     sigaddset (&set, SIGCHLD);
 172
 173 #ifdef HAVE_MAEMO
 174     sigaddset (&set, SIGRTMIN);
 175     {
 176         struct sigaction act = { .sa_handler = dummy_handler, };
 177         sigaction (SIGRTMIN, &act, NULL);
 178     }
 179 #endif
 180     /* Block all these signals */
 181     pthread_sigmask (SIG_SETMASK, &set, NULL);
 182
 183     /* Note that FromLocale() can be used before libvlc is initialized */
 184     const char *argv[i_argc + 3];
 185     int argc = 0;
 186
 187     argv[argc++] = "--no-ignore-config";
 188     argv[argc++] = "--media-library";
 189 #ifdef TOP_SRCDIR
 190     argv[argc++] = FromLocale ("--data-path="TOP_SRCDIR"/share");
 191 #endif
 192
 193     int i = 1;
 194 #ifdef __APPLE__
 195     /* When VLC.app is run by double clicking in Mac OS X, the 2nd arg
 196      * is the PSN - process serial number (a unique PID-ish thingie)
 197      * still ok for real Darwin & when run from command line
 198      * for example -psn_0_9306113 */
 199     if(i_argc >= 2 && !strncmp( ppsz_argv[1] , "-psn" , 4 ))
 200         i = 2;
 201 #endif
 202     for (; i < i_argc; i++)
 203         if ((argv[argc++] = FromLocale (ppsz_argv[i])) == NULL)
 204             return 1; // BOOM!
 205     argv[argc] = NULL;
 206
 207     vlc_enable_override ();
 208
 209     /* Initialize libvlc */
 210     libvlc_instance_t *vlc = libvlc_new (argc, argv);
 211     if (vlc == NULL)
 212         goto out;
 213
 214     libvlc_set_user_agent (vlc, "VLC media player", "VLC/"PACKAGE_VERSION);
 215
 216 #if !defined (HAVE_MAEMO) && !defined __APPLE__ && !defined (__OS2__)
 217     libvlc_add_intf (vlc, "globalhotkeys,none");
 218 #endif
 219     if (libvlc_add_intf (vlc, NULL))
 220         goto out;
 221
 222     libvlc_playlist_play (vlc, -1, 0, NULL);
 223
 224     /* Wait for a termination signal */
 225     pthread_t self = pthread_self ();
 226     libvlc_set_exit_handler (vlc, vlc_kill, &self);
 227
 228     /* Qt4 insists on catching SIGCHLD via signal handler. To work around that,
 229      * unblock it after all our child threads are created. */
 230     sigdelset (&set, SIGCHLD);
 231     pthread_sigmask (SIG_SETMASK, &set, NULL);
 232
 233     /* Do not dequeue SIGHUP if it is ignored (nohup) */
 234     if (signal_ignored (SIGHUP))
 235         sigdelset (&set, SIGHUP);
 236     /* Ignore SIGPIPE */
 237     sigdelset (&set, SIGPIPE);
 238
 239     int signum;
 240     sigwait (&set, &signum);
 241
 242     /* Restore default signal behaviour after 3 seconds */
 243     sigemptyset (&set);
 244     sigaddset (&set, SIGINT);
 245     sigaddset (&set, SIGALRM);
 246     signal (SIGINT, SIG_IGN);
 247     signal (SIGALRM, exit_timeout);
 248     pthread_sigmask (SIG_UNBLOCK, &set, NULL);
 249     alarm (3);
 250
 251     /* Cleanup */
 252 out:
 253     if (vlc != NULL)
 254         libvlc_release (vlc);
 255     for (int i = 2; i < argc; i++)
 256         LocaleFree (argv[i]);
 257
 258     return 0;
 259 }