bin/vlc.c

   1 /*****************************************************************************
   2  * vlc.c: the VLC player
   3  *****************************************************************************
   4  * Copyright (C) 1998-2013 the VideoLAN team
   5  *
   6  * Authors: Vincent Seguin <seguin@via.ecp.fr>
   7  *          Samuel Hocevar <sam@zoy.org>
   8  *          Gildas Bazin <gbazin@videolan.org>
   9  *          Derk-Jan Hartman <hartman at videolan dot org>
  10  *          Lots of other people, see the libvlc AUTHORS file
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc/vlc.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <stdbool.h>
  35 #include <string.h>
  36 #include <locale.h>
  37 #include <signal.h>
  38 #ifdef HAVE_PTHREAD_H
  39 # include <pthread.h>
  40 #endif
  41 #include <unistd.h>
  42
  43 #ifdef __OS2__
  44 # include <iconv.h>
  45
  46 # define pthread_t      int
  47 # define pthread_self() _gettid()
  48 # define pthread_sigmask(h, i, o) sigprocmask(h, i, o)
  49
  50 static char *FromSystem(const void *str)
  51 {
  52     iconv_t handle = iconv_open ("UTF-8", "");
  53     if (handle == (iconv_t)(-1))
  54         return NULL;
  55
  56     size_t str_len = strlen (str);
  57     char *out = NULL;
  58     for (unsigned mul = 4; mul < 8; mul++)
  59     {
  60         size_t in_size = str_len;
  61         const char *in = str;
  62         size_t out_max = mul * str_len;
  63         char *tmp = out = malloc (1 + out_max);
  64         if (!out)
  65             break;
  66
  67         if (iconv (handle, &in, &in_size, &tmp, &out_max) != (size_t)(-1)) {
  68             *tmp = '\0';
  69             break;
  70         }
  71         free(out);
  72         out = NULL;
  73
  74         if (errno != E2BIG)
  75             break;
  76     }
  77     iconv_close(handle);
  78     return out;
  79 }
  80 #endif
  81
  82 extern void vlc_enable_override (void);
  83
  84 static bool signal_ignored (int signum)
  85 {
  86     struct sigaction sa;
  87
  88     if (sigaction (signum, NULL, &sa))
  89         return false;
  90     return ((sa.sa_flags & SA_SIGINFO)
  91             ? (void *)sa.sa_sigaction : (void *)sa.sa_handler) == SIG_IGN;
  92 }
  93
  94 static void vlc_kill (void *data)
  95 {
  96 #ifndef __OS2__
  97     pthread_t *ps = data;
  98
  99     pthread_kill (*ps, SIGTERM);
 100 #else
 101     // send a signal to the main thread
 102     kill (getpid(), SIGTERM);
 103 #endif
 104 }
 105
 106 static void exit_timeout (int signum)
 107 {
 108     (void) signum;
 109     signal (SIGINT, SIG_DFL);
 110 }
 111
 112 /*****************************************************************************
 113  * main: parse command line, start interface and spawn threads.
 114  *****************************************************************************/
 115 int main(int argc, const char *argv[])
 116 {
 117     /* The so-called POSIX-compliant MacOS X reportedly processes SIGPIPE even
 118      * if it is blocked in all thread.
 119      * Note: this is NOT an excuse for not protecting against SIGPIPE. If
 120      * LibVLC runs outside of VLC, we cannot rely on this code snippet. */
 121     signal (SIGPIPE, SIG_IGN);
 122     /* Restore SIGCHLD in case our parent process ignores it. */
 123     signal (SIGCHLD, SIG_DFL);
 124
 125 #ifndef NDEBUG
 126     /* Activate malloc checking routines to detect heap corruptions. */
 127     setenv ("MALLOC_CHECK_", "2", 1);
 128
 129     /* Disable the ugly Gnome crash dialog so that we properly segfault */
 130     setenv ("GNOME_DISABLE_CRASH_DIALOG", "1", 1);
 131 #endif
 132
 133 #ifdef TOP_BUILDDIR
 134     setenv ("VLC_PLUGIN_PATH", TOP_BUILDDIR"/modules", 1);
 135     setenv ("VLC_DATA_PATH", TOP_SRCDIR"/share", 1);
 136     setenv ("VLC_LIB_PATH", TOP_BUILDDIR"/modules", 1);
 137 #endif
 138
 139     /* Clear the X.Org startup notification ID. Otherwise the UI might try to
 140      * change the environment while the process is multi-threaded. That could
 141      * crash. Screw you X.Org. Next time write a thread-safe specification. */
 142     unsetenv ("DESKTOP_STARTUP_ID");
 143
 144 #ifndef ALLOW_RUN_AS_ROOT
 145     if (geteuid () == 0)
 146     {
 147         fprintf (stderr, "VLC is not supposed to be run as root. Sorry.\n"
 148         "If you need to use real-time priorities and/or privileged TCP ports\n"
 149         "you can use %s-wrapper (make sure it is Set-UID root and\n"
 150         "cannot be run by non-trusted users first).\n", argv[0]);
 151         return 1;
 152     }
 153 #endif
 154
 155     setlocale (LC_ALL, "");
 156
 157     if (isatty (STDERR_FILENO))
 158         /* This message clutters error logs. It is printed only on a TTY.
 159          * Fortunately, LibVLC prints version info with -vv anyway. */
 160         fprintf (stderr, "VLC media player %s (revision %s)\n",
 161                  libvlc_get_version(), libvlc_get_changeset());
 162
 163     sigset_t set;
 164
 165     sigemptyset (&set);
 166     /* VLC uses sigwait() to dequeue interesting signals.
 167      * For this to work, those signals must be blocked in all threads,
 168      * including the thread calling sigwait() (see the man page for details).
 169      *
 170      * There are two advantages to sigwait() over traditional signal handlers:
 171      *  - delivery is synchronous: no need to worry about async-safety,
 172      *  - EINTR is not generated: other threads need not handle that error.
 173      * That being said, some LibVLC programs do not use sigwait(). Therefore
 174      * EINTR must still be handled cleanly, notably from poll() calls.
 175      *
 176      * Signals that request a clean shutdown, and force an unclean shutdown
 177      * if they are triggered again 2+ seconds later.
 178      * We have to handle SIGTERM cleanly because of daemon mode. */
 179     sigaddset (&set, SIGINT);
 180     sigaddset (&set, SIGHUP);
 181     sigaddset (&set, SIGQUIT);
 182     sigaddset (&set, SIGTERM);
 183
 184     /* SIGPIPE can happen and would crash the process. On modern systems,
 185      * the MSG_NOSIGNAL flag protects socket write operations against SIGPIPE.
 186      * But we still need to block SIGPIPE when:
 187      *  - writing to pipes,
 188      *  - using write() instead of send() for code not specific to sockets.
 189      * LibVLC code assumes that SIGPIPE is blocked. Other LibVLC applications
 190      * shall block it (or handle it somehow) too.
 191      */
 192     sigaddset (&set, SIGPIPE);
 193
 194     /* SIGCHLD must be dequeued to clean up zombie child processes.
 195      * Furthermore the handler must not be set to SIG_IGN (see above).
 196      * We cannot pragmatically handle EINTR, short reads and short writes
 197      * in every code paths (including underlying libraries). So we just
 198      * block SIGCHLD in all threads, and dequeue it below. */
 199     sigaddset (&set, SIGCHLD);
 200
 201     /* Block all these signals */
 202     pthread_t self = pthread_self ();
 203     pthread_sigmask (SIG_SETMASK, &set, NULL);
 204
 205     const char *args[argc + 3];
 206     int count = 0;
 207
 208     args[count++] = "--no-ignore-config";
 209     args[count++] = "--media-library";
 210 #ifdef HAVE_DBUS
 211     args[count++] = "--dbus";
 212 #endif
 213
 214 #ifdef __OS2__
 215     for (int i = 1; i < argc; i++)
 216         if ((args[count++] = FromSystem(argv[i])) == NULL)
 217         {
 218             fprintf (stderr, "Converting '%s' to UTF-8 failed.\n", argv[i]);
 219             return 1;
 220         }
 221 #else
 222     memcpy(args + count, argv + 1, (argc - 1) * sizeof (*argv));
 223     count += (argc - 1);
 224 #endif
 225     args[count] = NULL;
 226
 227     vlc_enable_override ();
 228
 229     /* Initialize libvlc */
 230     libvlc_instance_t *vlc = libvlc_new(count, args);
 231     if (vlc == NULL)
 232         return 1;
 233
 234     int ret = 1;
 235     libvlc_set_exit_handler (vlc, vlc_kill, &self);
 236     libvlc_set_app_id (vlc, "org.VideoLAN.VLC", PACKAGE_VERSION, PACKAGE_NAME);
 237     libvlc_set_user_agent (vlc, "VLC media player", "VLC/"PACKAGE_VERSION);
 238
 239     if (libvlc_add_intf (vlc, NULL))
 240     {
 241         fprintf(stderr, "%s: cannot start any interface. Exiting.\n", argv[0]);
 242         goto out;
 243     }
 244
 245     libvlc_playlist_play (vlc);
 246
 247     /* Qt insists on catching SIGCHLD via signal handler. To work around that,
 248      * unblock it after all our child threads are created. */
 249     sigdelset (&set, SIGCHLD);
 250     pthread_sigmask (SIG_SETMASK, &set, NULL);
 251
 252     /* Do not dequeue SIGHUP if it is ignored (nohup) */
 253     if (signal_ignored (SIGHUP))
 254         sigdelset (&set, SIGHUP);
 255     /* Ignore SIGPIPE */
 256     sigdelset (&set, SIGPIPE);
 257
 258     int signum;
 259     sigwait (&set, &signum);
 260
 261     /* Restore default signal behaviour after 3 seconds */
 262     sigemptyset (&set);
 263     sigaddset (&set, SIGINT);
 264     sigaddset (&set, SIGALRM);
 265     signal (SIGINT, SIG_IGN);
 266     signal (SIGALRM, exit_timeout);
 267     pthread_sigmask (SIG_UNBLOCK, &set, NULL);
 268     alarm (3);
 269
 270     ret = 0;
 271     /* Cleanup */
 272 out:
 273     libvlc_release (vlc);
 274 #ifdef __OS2__
 275     for (int i = count - argc + 1; i < count; i++)
 276         free(args[i]);
 277 #endif
 278     return ret;
 279 }