X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=bin%2Fvlc.c;h=2b1871941531be992e7c75b141a638e7e9d61fbb;hb=9934897a3bfcfb8518ac35d9f1e24c6ce18761af;hp=447b808d5438cf2e85f88cddc8a557dbac57ed82;hpb=ae16ebf3524a76da5b2584451bcf0f0f9fc820a4;p=vlc diff --git a/bin/vlc.c b/bin/vlc.c index 447b808d54..2b18719415 100644 --- a/bin/vlc.c +++ b/bin/vlc.c @@ -32,30 +32,56 @@ #include #include #include +#include #include +#include +#ifdef HAVE_PTHREAD_H +# include +#endif +#include #ifdef __APPLE__ #include #endif +#ifdef __OS2__ +# define pthread_t int +# define pthread_self() _gettid() +#endif + /* Explicit HACK */ extern void LocaleFree (const char *); extern char *FromLocale (const char *); extern void vlc_enable_override (void); -#include -#include -#include -#include -#include +static bool signal_ignored (int signum) +{ + struct sigaction sa; + + if (sigaction (signum, NULL, &sa)) + return false; + return ((sa.sa_flags & SA_SIGINFO) + ? (void *)sa.sa_sigaction : (void *)sa.sa_handler) == SIG_IGN; +} + +static void vlc_kill (void *data) +{ +#ifndef __OS2__ + pthread_t *ps = data; + + pthread_kill (*ps, SIGTERM); +#else + // send a signal to the main thread + kill (getpid(), SIGTERM); +#endif +} -#ifdef HAVE_MAEMO -static void dummy_handler (int signum) +static void exit_timeout (int signum) { (void) signum; + signal (SIGINT, SIG_DFL); } -#endif /***************************************************************************** * main: parse command line, start interface and spawn threads. @@ -63,32 +89,29 @@ static void dummy_handler (int signum) int main( int i_argc, const char *ppsz_argv[] ) { /* The so-called POSIX-compliant MacOS X reportedly processes SIGPIPE even - * if it is blocked in all thread. Also some libraries want SIGPIPE blocked - * as they have no clue about signal masks. + * if it is blocked in all thread. * Note: this is NOT an excuse for not protecting against SIGPIPE. If * LibVLC runs outside of VLC, we cannot rely on this code snippet. */ signal (SIGPIPE, SIG_IGN); - /* Restore default for SIGCHLD in case parent ignores it. */ + /* Restore SIGCHLD in case our parent process ignores it. */ signal (SIGCHLD, SIG_DFL); -#ifdef HAVE_SETENV -# ifndef NDEBUG +#ifndef NDEBUG /* Activate malloc checking routines to detect heap corruptions. */ setenv ("MALLOC_CHECK_", "2", 1); /* Disable the ugly Gnome crash dialog so that we properly segfault */ setenv ("GNOME_DISABLE_CRASH_DIALOG", "1", 1); -# endif +#endif - /* Make Xlib hide visuals with an alphachannel. Ensure that Qt4 will not - * use the alpha channel for the embedded video window. */ - setenv ("XLIB_SKIP_ARGB_VISUALS", "1", 1); +#ifdef TOP_BUILDDIR + setenv ("VLC_PLUGIN_PATH", TOP_BUILDDIR"/modules", 1); +#endif /* Clear the X.Org startup notification ID. Otherwise the UI might try to * change the environment while the process is multi-threaded. That could * crash. Screw you X.Org. Next time write a thread-safe specification. */ unsetenv ("DESKTOP_STARTUP_ID"); -#endif #ifndef ALLOW_RUN_AS_ROOT if (geteuid () == 0) @@ -103,65 +126,59 @@ int main( int i_argc, const char *ppsz_argv[] ) setlocale (LC_ALL, ""); -#ifndef __APPLE__ - /* This clutters OSX GUI error logs */ - fprintf( stderr, "VLC media player %s (revision %s)\n", - libvlc_get_version(), libvlc_get_changeset() ); -#endif + if (isatty (STDERR_FILENO)) + /* This message clutters error logs. It is printed only on a TTY. + * Fortunately, LibVLC prints version info with -vv anyway. */ + fprintf (stderr, "VLC media player %s (revision %s)\n", + libvlc_get_version(), libvlc_get_changeset()); + + sigset_t set; - /* Synchronously intercepted POSIX signals. + sigemptyset (&set); + /* VLC uses sigwait() to dequeue interesting signals. + * For this to work, those signals must be blocked in all threads, + * including the thread calling sigwait() (see the man page for details). * - * In a threaded program such as VLC, the only sane way to handle signals - * is to block them in all threads but one - this is the only way to - * predict which thread will receive them. If any piece of code depends - * on delivery of one of this signal it is intrinsically not thread-safe - * and MUST NOT be used in VLC, whether we like it or not. - * There is only one exception: if the signal is raised with - * pthread_kill() - we do not use this in LibVLC but some pthread - * implementations use them internally. You should really use conditions - * for thread synchronization anyway. + * There are two advantages to sigwait() over traditional signal handlers: + * - delivery is synchronous: no need to worry about async-safety, + * - EINTR is not generated: other threads need not handle that error. + * That being said, some LibVLC programs do not use sigwait(). Therefore + * EINTR must still be handled cleanly, notably from poll() calls. * - * Signal that request a clean shutdown, and force an unclean shutdown + * Signals that request a clean shutdown, and force an unclean shutdown * if they are triggered again 2+ seconds later. - * We have to handle SIGTERM cleanly because of daemon mode. - * Note that we set the signals after the vlc_create call. */ - static const int sigs[] = { - SIGINT, SIGHUP, SIGQUIT, SIGTERM, - /* Signals that cause a no-op: - * - SIGPIPE might happen with sockets and would crash VLC. It MUST be - * blocked by any LibVLC-dependent application, not just VLC. - * - SIGCHLD comes after exec*() (such as httpd CGI support) and must - * be dequeued to cleanup zombie processes. + * We have to handle SIGTERM cleanly because of daemon mode. */ + sigaddset (&set, SIGINT); + sigaddset (&set, SIGHUP); + sigaddset (&set, SIGQUIT); + sigaddset (&set, SIGTERM); + + /* SIGPIPE can happen and would crash the process. On modern systems, + * the MSG_NOSIGNAL flag protects socket write operations against SIGPIPE. + * But we still need to block SIGPIPE when: + * - writing to pipes, + * - using write() instead of send() for code not specific to sockets. + * LibVLC code assumes that SIGPIPE is blocked. Other LibVLC applications + * shall block it (or handle it somehow) too. */ - SIGPIPE, SIGCHLD - }; + sigaddset (&set, SIGPIPE); - sigset_t set; - sigemptyset (&set); - for (unsigned i = 0; i < sizeof (sigs) / sizeof (sigs[0]); i++) - sigaddset (&set, sigs[i]); -#ifdef HAVE_MAEMO - sigaddset (&set, SIGRTMIN); - { - struct sigaction act = { .sa_handler = dummy_handler, }; - sigaction (SIGRTMIN, &act, NULL); - } -#endif + /* SIGCHLD must be dequeued to clean up zombie child processes. + * Furthermore the handler must not be set to SIG_IGN (see above). + * We cannot pragmatically handle EINTR, short reads and short writes + * in every code paths (including underlying libraries). So we just + * block SIGCHLD in all threads, and dequeue it below. */ + sigaddset (&set, SIGCHLD); /* Block all these signals */ - pthread_sigmask (SIG_BLOCK, &set, NULL); - sigdelset (&set, SIGPIPE); - sigdelset (&set, SIGCHLD); + pthread_sigmask (SIG_SETMASK, &set, NULL); /* Note that FromLocale() can be used before libvlc is initialized */ - const char *argv[i_argc + 4]; + const char *argv[i_argc + 3]; int argc = 0; argv[argc++] = "--no-ignore-config"; - argv[argc++] = "--user-agent=\"VLC media player\""; -#ifdef TOP_BUILDDIR - argv[argc++] = FromLocale ("--plugin-path="TOP_BUILDDIR"/modules"); -#endif + argv[argc++] = "--media-library"; #ifdef TOP_SRCDIR argv[argc++] = FromLocale ("--data-path="TOP_SRCDIR"/share"); #endif @@ -184,34 +201,52 @@ int main( int i_argc, const char *ppsz_argv[] ) /* Initialize libvlc */ libvlc_instance_t *vlc = libvlc_new (argc, argv); + if (vlc == NULL) + goto out; - if (vlc != NULL) - { - if (libvlc_add_intf (vlc, "signals")) - pthread_sigmask (SIG_UNBLOCK, &set, NULL); -#if !defined (HAVE_MAEMO) - libvlc_add_intf (vlc, "globalhotkeys,none"); + libvlc_set_user_agent (vlc, "VLC media player", "VLC/"PACKAGE_VERSION); + +#if !defined (HAVE_MAEMO) && !defined __APPLE__ && !defined (__OS2__) + libvlc_add_intf (vlc, "globalhotkeys,none"); #endif - if (libvlc_add_intf (vlc, NULL) == 0) - { - libvlc_playlist_play (vlc, -1, 0, NULL); - libvlc_wait (vlc); - } - libvlc_release (vlc); - } + if (libvlc_add_intf (vlc, NULL)) + goto out; + + libvlc_playlist_play (vlc, -1, 0, NULL); - for (int i = 1; i < argc; i++) + /* Wait for a termination signal */ + pthread_t self = pthread_self (); + libvlc_set_exit_handler (vlc, vlc_kill, &self); + + /* Qt4 insists on catching SIGCHLD via signal handler. To work around that, + * unblock it after all our child threads are created. */ + sigdelset (&set, SIGCHLD); + pthread_sigmask (SIG_SETMASK, &set, NULL); + + /* Do not dequeue SIGHUP if it is ignored (nohup) */ + if (signal_ignored (SIGHUP)) + sigdelset (&set, SIGHUP); + /* Ignore SIGPIPE */ + sigdelset (&set, SIGPIPE); + + int signum; + sigwait (&set, &signum); + + /* Restore default signal behaviour after 3 seconds */ + sigemptyset (&set); + sigaddset (&set, SIGINT); + sigaddset (&set, SIGALRM); + signal (SIGINT, SIG_IGN); + signal (SIGALRM, exit_timeout); + pthread_sigmask (SIG_UNBLOCK, &set, NULL); + alarm (3); + + /* Cleanup */ +out: + if (vlc != NULL) + libvlc_release (vlc); + for (int i = 2; i < argc; i++) LocaleFree (argv[i]); -#ifdef RTLD_NOLOAD - /* Avoid crash in KIO scheduler cleanup. */ - /* This is ugly, but we get way too many crash reports due to this. */ - if (dlopen ("libkio.so.5", RTLD_LAZY|RTLD_LOCAL|RTLD_NOLOAD) != NULL) - { - fprintf (stderr, "KIO present. Unclean shutdown!\n" - " (see http://bugs.kde.org/show_bug.cgi?id=234484 for details)\n"); - _exit (0); - } -#endif return 0; }