threads.c

VLC Player Source Code

    p_condvar->init = 9999;
    return 0;

#endif
}

/*****************************************************************************
 * vlc_cond_destroy: destroy a condition, inner version
 *****************************************************************************/
void __vlc_cond_destroy( const char * psz_file, int i_line, vlc_cond_t *p_condvar )
{
#if defined( LIBVLC_USE_PTHREAD )
    int val = pthread_cond_destroy( p_condvar );
    VLC_THREAD_ASSERT ("destroying condition");

#elif defined( UNDER_CE ) || defined( WIN32 )
    VLC_UNUSED( psz_file); VLC_UNUSED( i_line );

    CloseHandle( *p_condvar );

#elif defined( HAVE_KERNEL_SCHEDULER_H )
    p_condvar->init = 0;

#endif
}

/*****************************************************************************
 * vlc_tls_create: create a thread-local variable
 *****************************************************************************/
int vlc_threadvar_create( vlc_threadvar_t *p_tls, void (*destr) (void *) )
{
    int i_ret;

#if defined( LIBVLC_USE_PTHREAD )
    i_ret =  pthread_key_create( p_tls, destr );
#elif defined( UNDER_CE )
    i_ret = ENOSYS;
#elif defined( WIN32 )
    /* FIXME: remember/use the destr() callback and stop leaking whatever */
    *p_tls = TlsAlloc();
    i_ret = (*p_tls == TLS_OUT_OF_INDEXES) ? EAGAIN : 0;
#else
# error Unimplemented!
#endif
    return i_ret;
}

void vlc_threadvar_delete (vlc_threadvar_t *p_tls)
{
#if defined( LIBVLC_USE_PTHREAD )
    pthread_key_delete (*p_tls);
#elif defined( UNDER_CE )
#elif defined( WIN32 )
    TlsFree (*p_tls);
#else
# error Unimplemented!
#endif
}

struct vlc_thread_boot
{
    void * (*entry) (vlc_object_t *);
    vlc_object_t *object;
};

#if defined (LIBVLC_USE_PTHREAD)
# define THREAD_RTYPE void *
# define THREAD_RVAL  NULL
#elif defined (WIN32)
# define THREAD_RTYPE __stdcall unsigned
# define THREAD_RVAL 0
#endif

static THREAD_RTYPE thread_entry (void *data)
{
    vlc_object_t *obj = ((struct vlc_thread_boot *)data)->object;
    void *(*func) (vlc_object_t *) = ((struct vlc_thread_boot *)data)->entry;

    free (data);
#ifndef NDEBUG
    vlc_threadvar_set (&thread_object_key, obj);
#endif
    msg_Dbg (obj, "thread started");
    func (obj);
    msg_Dbg (obj, "thread ended");

    return THREAD_RVAL;
}

/*****************************************************************************
 * vlc_thread_create: create a thread, inner version
 *****************************************************************************
 * Note that i_priority is only taken into account on platforms supporting
 * userland real-time priority threads.
 *****************************************************************************/
int __vlc_thread_create( vlc_object_t *p_this, const char * psz_file, int i_line,
                         const char *psz_name, void * ( *func ) ( vlc_object_t * ),
                         int i_priority, bool b_wait )
{
    int i_ret;
    vlc_object_internals_t *p_priv = vlc_internals( p_this );

    struct vlc_thread_boot *boot = malloc (sizeof (*boot));
    if (boot == NULL)
        return errno;
    boot->entry = func;
    boot->object = p_this;

    vlc_object_lock( p_this );

    /* Make sure we don't re-create a thread if the object has already one */
    assert( !p_priv->b_thread );

#if defined( LIBVLC_USE_PTHREAD )
    pthread_attr_t attr;
    pthread_attr_init (&attr);

    /* Block the signals that signals interface plugin handles.
     * If the LibVLC caller wants to handle some signals by itself, it should
     * block these before whenever invoking LibVLC. And it must obviously not
     * start the VLC signals interface plugin.
     *
     * LibVLC will normally ignore any interruption caused by an asynchronous
     * signal during a system call. But there may well be some buggy cases
     * where it fails to handle EINTR (bug reports welcome). Some underlying
     * libraries might also not handle EINTR properly.
     */
    sigset_t set, oldset;
    sigemptyset (&set);
    sigdelset (&set, SIGHUP);
    sigaddset (&set, SIGINT);
    sigaddset (&set, SIGQUIT);
    sigaddset (&set, SIGTERM);

    sigaddset (&set, SIGPIPE); /* We don't want this one, really! */
    pthread_sigmask (SIG_BLOCK, &set, &oldset);

#ifndef __APPLE__
    if( config_GetInt( p_this, "rt-priority" ) > 0 )
#endif
    {
        struct sched_param p = { .sched_priority = i_priority, };
        int policy;

        /* Hack to avoid error msg */
        if( config_GetType( p_this, "rt-offset" ) )
            p.sched_priority += config_GetInt( p_this, "rt-offset" );
        if( p.sched_priority <= 0 )
            p.sched_priority += sched_get_priority_max (policy = SCHED_OTHER);
        else
            p.sched_priority += sched_get_priority_min (policy = SCHED_RR);

        pthread_attr_setschedpolicy (&attr, policy);
        pthread_attr_setschedparam (&attr, &p);
    }

    i_ret = pthread_create( &p_priv->thread_id, &attr, thread_entry, boot );
    pthread_sigmask (SIG_SETMASK, &oldset, NULL);
    pthread_attr_destroy (&attr);

#elif defined( WIN32 ) || defined( UNDER_CE )
    /* When using the MSVCRT C library you have to use the _beginthreadex
     * function instead of CreateThread, otherwise you'll end up with
     * memory leaks and the signal functions not working (see Microsoft
     * Knowledge Base, article 104641) */
#if defined( UNDER_CE )
    HANDLE hThread = CreateThread( NULL, 0, thread_entry,
                                  (LPVOID)boot, CREATE_SUSPENDED, NULL );
#else
    HANDLE hThread = (HANDLE)(uintptr_t)
        _beginthreadex( NULL, 0, thread_entry, boot, CREATE_SUSPENDED, NULL );
#endif
    if( hThread )
    {
        p_priv->thread_id = hThread;
        ResumeThread (hThread);
        i_ret = 0;
        if( i_priority && !SetThreadPriority (hThread, i_priority) )
        {
            msg_Warn( p_this, "couldn't set a faster priority" );
            i_priority = 0;
        }
    }
    else
        i_ret = errno;

#elif defined( HAVE_KERNEL_SCHEDULER_H )
    p_priv->thread_id = spawn_thread( (thread_func)thread_entry, psz_name,
                                      i_priority, p_data );
    i_ret = resume_thread( p_priv->thread_id );

#endif

    if( i_ret == 0 )
    {
        if( b_wait )
        {
            msg_Dbg( p_this, "waiting for thread initialization" );
            vlc_object_wait( p_this );
        }

        p_priv->b_thread = true;
        msg_Dbg( p_this, "thread %lu (%s) created at priority %d (%s:%d)",
                 (unsigned long)p_priv->thread_id, psz_name, i_priority,
                 psz_file, i_line );
    }
    else
    {
        errno = i_ret;
        msg_Err( p_this, "%s thread could not be created at %s:%d (%m)",
                         psz_name, psz_file, i_line );
    }

    vlc_object_unlock( p_this );
    return i_ret;
}

/*****************************************************************************
 * vlc_thread_set_priority: set the priority of the current thread when we
 * couldn't set it in vlc_thread_create (for instance for the main thread)
 *****************************************************************************/
int __vlc_thread_set_priority( vlc_object_t *p_this, const char * psz_file,
                               int i_line, int i_priority )
{
    vlc_object_internals_t *p_priv = vlc_internals( p_this );

    if( !p_priv->b_thread )
    {
        msg_Err( p_this, "couldn't set priority of non-existent thread" );
        return ESRCH;
    }

#if defined( LIBVLC_USE_PTHREAD )
# ifndef __APPLE__
    if( config_GetInt( p_this, "rt-priority" ) > 0 )
# endif
    {
        int i_error, i_policy;
        struct sched_param param;

        memset( &param, 0, sizeof(struct sched_param) );
        if( config_GetType( p_this, "rt-offset" ) )
            i_priority += config_GetInt( p_this, "rt-offset" );
        if( i_priority <= 0 )
        {
            param.sched_priority = (-1) * i_priority;
            i_policy = SCHED_OTHER;
        }
        else
        {
            param.sched_priority = i_priority;
            i_policy = SCHED_RR;
        }
        if( (i_error = pthread_setschedparam( p_priv->thread_id,
                                              i_policy, &param )) )
        {
            errno = i_error;
            msg_Warn( p_this, "couldn't set thread priority (%s:%d): %m",
                      psz_file, i_line );
            i_priority = 0;
        }
    }

#elif defined( WIN32 ) || defined( UNDER_CE )
    VLC_UNUSED( psz_file); VLC_UNUSED( i_line );

    if( !SetThreadPriority(p_priv->thread_id, i_priority) )
    {
        msg_Warn( p_this, "couldn't set a faster priority" );
        return 1;
    }

#endif

    return 0;
}

/*****************************************************************************
 * vlc_thread_join: wait until a thread exits, inner version
 *****************************************************************************/
void __vlc_thread_join( vlc_object_t *p_this, const char * psz_file, int i_line )
{
    vlc_object_internals_t *p_priv = vlc_internals( p_this );
    int i_ret = 0;

#if defined( LIBVLC_USE_PTHREAD )
    /* Make sure we do return if we are calling vlc_thread_join()
     * from the joined thread */
    if (pthread_equal (pthread_self (), p_priv->thread_id))
    {
        msg_Warn (p_this, "joining the active thread (VLC might crash)");
        i_ret = pthread_detach (p_priv->thread_id);
    }
    else
        i_ret = pthread_join (p_priv->thread_id, NULL);

#elif defined( UNDER_CE ) || defined( WIN32 )
    HMODULE hmodule;
    BOOL (WINAPI *OurGetThreadTimes)( HANDLE, FILETIME*, FILETIME*,
                                      FILETIME*, FILETIME* );
    FILETIME create_ft, exit_ft, kernel_ft, user_ft;
    int64_t real_time, kernel_time, user_time;
    HANDLE hThread;

    /*
    ** object will close its thread handle when destroyed, duplicate it here
    ** to be on the safe side
    */
    if( ! DuplicateHandle(GetCurrentProcess(),
            p_priv->thread_id,
            GetCurrentProcess(),
            &hThread,
            0,
            FALSE,
            DUPLICATE_SAME_ACCESS) )
    {
        p_priv->b_thread = false;
        i_ret = GetLastError();
        goto error;
    }

    WaitForSingleObject( hThread, INFINITE );

#if defined( UNDER_CE )
    hmodule = GetModuleHandle( _T("COREDLL") );
#else
    hmodule = GetModuleHandle( _T("KERNEL32") );
#endif
    OurGetThreadTimes = (BOOL (WINAPI*)( HANDLE, FILETIME*, FILETIME*,
                                         FILETIME*, FILETIME* ))
        GetProcAddress( hmodule, _T("GetThreadTimes") );

    if( OurGetThreadTimes &&
        OurGetThreadTimes( hThread,
                           &create_ft, &exit_ft, &kernel_ft, &user_ft ) )
    {
        real_time =
          ((((int64_t)exit_ft.dwHighDateTime)<<32)| exit_ft.dwLowDateTime) -
          ((((int64_t)create_ft.dwHighDateTime)<<32)| create_ft.dwLowDateTime);
        real_time /= 10;

        kernel_time =
          ((((int64_t)kernel_ft.dwHighDateTime)<<32)|
           kernel_ft.dwLowDateTime) / 10;

        user_time =
          ((((int64_t)user_ft.dwHighDateTime)<<32)|
           user_ft.dwLowDateTime) / 10;

        msg_Dbg( p_this, "thread times: "
                 "real %"PRId64"m%fs, kernel %"PRId64"m%fs, user %"PRId64"m%fs",
                 real_time/60/1000000,
                 (double)((real_time%(60*1000000))/1000000.0),
                 kernel_time/60/1000000,
                 (double)((kernel_time%(60*1000000))/1000000.0),
                 user_time/60/1000000,
                 (double)((user_time%(60*1000000))/1000000.0) );
    }
    CloseHandle( hThread );
error:

#elif defined( HAVE_KERNEL_SCHEDULER_H )
    int32_t exit_value;
    i_ret = (B_OK == wait_for_thread( p_priv->thread_id, &exit_value ));

#endif

    if( i_ret )
    {
        errno = i_ret;
        msg_Err( p_this, "thread_join(%lu) failed at %s:%d (%m)",
                         (unsigned long)p_priv->thread_id, psz_file, i_line );
    }
    else
        msg_Dbg( p_this, "thread %lu joined (%s:%d)",
                         (unsigned long)p_priv->thread_id, psz_file, i_line );

    p_priv->b_thread = false;
}