X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=include%2Fvlc_threads.h;h=3d7a6d93426309cad7216e98bad138bf4e2d54a9;hb=0f58689cb81d5ab078e40f510a3ef55d6650f6b6;hp=72dac3009a096718ca88c5e93811868eebaf65fd;hpb=2a64087b4cb7fdce80d8c22dfbc8b22b27f7b5b2;p=vlc diff --git a/include/vlc_threads.h b/include/vlc_threads.h index 72dac3009a..3d7a6d9342 100644 --- a/include/vlc_threads.h +++ b/include/vlc_threads.h @@ -3,7 +3,7 @@ * This header provides portable declarations for mutexes & conditions ***************************************************************************** * Copyright (C) 1999, 2002 the VideoLAN team - * $Id$ + * Copyright © 2007-2008 Rémi Denis-Courmont * * Authors: Jean-Marc Dressler * Samuel Hocevar @@ -25,12 +25,14 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ -#if !defined( __LIBVLC__ ) - #error You are not libvlc or one of its plugins. You cannot include this file -#endif +#ifndef VLC_THREADS_H_ +#define VLC_THREADS_H_ -#ifndef _VLC_THREADS_H_ -#define _VLC_THREADS_H_ +/** + * \file + * This file defines structures and functions for handling threads in vlc + * + */ #if defined( UNDER_CE ) /* WinCE API */ @@ -38,13 +40,9 @@ # include /* Win32 API */ # include -#elif defined( SYS_BEOS ) /* BeOS */ -# include -# include -# include - #else /* pthreads (like Linux & BSD) */ # define LIBVLC_USE_PTHREAD 1 +# define LIBVLC_USE_PTHREAD_CANCEL 1 # define _APPLE_C_SOURCE 1 /* Proper pthread semantics on OSX */ # include /* lldiv_t definition (only in C99) */ @@ -62,28 +60,20 @@ /* Thread priorities */ #ifdef __APPLE__ -# define VLC_THREAD_PRIORITY_LOW (-47) -# define VLC_THREAD_PRIORITY_INPUT 37 -# define VLC_THREAD_PRIORITY_AUDIO 37 -# define VLC_THREAD_PRIORITY_VIDEO (-47) -# define VLC_THREAD_PRIORITY_OUTPUT 37 -# define VLC_THREAD_PRIORITY_HIGHEST 37 - -#elif defined(SYS_BEOS) -# define VLC_THREAD_PRIORITY_LOW 5 -# define VLC_THREAD_PRIORITY_INPUT 10 -# define VLC_THREAD_PRIORITY_AUDIO 10 -# define VLC_THREAD_PRIORITY_VIDEO 5 -# define VLC_THREAD_PRIORITY_OUTPUT 15 -# define VLC_THREAD_PRIORITY_HIGHEST 15 +# define VLC_THREAD_PRIORITY_LOW 0 +# define VLC_THREAD_PRIORITY_INPUT 22 +# define VLC_THREAD_PRIORITY_AUDIO 22 +# define VLC_THREAD_PRIORITY_VIDEO 0 +# define VLC_THREAD_PRIORITY_OUTPUT 22 +# define VLC_THREAD_PRIORITY_HIGHEST 22 #elif defined(LIBVLC_USE_PTHREAD) -# define VLC_THREAD_PRIORITY_LOW 0 -# define VLC_THREAD_PRIORITY_INPUT 20 -# define VLC_THREAD_PRIORITY_AUDIO 10 -# define VLC_THREAD_PRIORITY_VIDEO 0 -# define VLC_THREAD_PRIORITY_OUTPUT 30 -# define VLC_THREAD_PRIORITY_HIGHEST 40 +# define VLC_THREAD_PRIORITY_LOW 0 +# define VLC_THREAD_PRIORITY_INPUT 10 +# define VLC_THREAD_PRIORITY_AUDIO 5 +# define VLC_THREAD_PRIORITY_VIDEO 0 +# define VLC_THREAD_PRIORITY_OUTPUT 15 +# define VLC_THREAD_PRIORITY_HIGHEST 20 #elif defined(WIN32) || defined(UNDER_CE) /* Define different priorities for WinNT/2K/XP and Win9x/Me */ @@ -120,43 +110,17 @@ typedef pthread_cond_t vlc_cond_t; typedef pthread_key_t vlc_threadvar_t; #elif defined( WIN32 ) || defined( UNDER_CE ) -typedef HANDLE vlc_thread_t; - -typedef BOOL (WINAPI *SIGNALOBJECTANDWAIT) ( HANDLE, HANDLE, DWORD, BOOL ); - -typedef HANDLE vlc_mutex_t; - typedef struct { - volatile int i_waiting_threads; - HANDLE event; -} vlc_cond_t; + HANDLE handle; + void *(*entry) (void *); + void *data; +} *vlc_thread_t; +typedef HANDLE vlc_mutex_t; +typedef HANDLE vlc_cond_t; typedef DWORD vlc_threadvar_t; -#elif defined( SYS_BEOS ) -/* This is the BeOS implementation of the vlc threads, note that the mutex is - * not a real mutex and the cond_var is not like a pthread cond_var but it is - * enough for what we need */ - -typedef thread_id vlc_thread_t; - -typedef struct -{ - int32_t init; - sem_id lock; -} vlc_mutex_t; - -typedef struct -{ - int32_t init; - thread_id thread; -} vlc_cond_t; - -typedef struct -{ -} vlc_threadvar_t; - #endif #if defined( WIN32 ) && !defined ETIMEDOUT @@ -168,272 +132,150 @@ typedef struct *****************************************************************************/ VLC_EXPORT( int, vlc_mutex_init, ( vlc_mutex_t * ) ); VLC_EXPORT( int, vlc_mutex_init_recursive, ( vlc_mutex_t * ) ); -VLC_EXPORT( void, __vlc_mutex_destroy, ( const char *, int, vlc_mutex_t * ) ); -VLC_EXPORT( int, __vlc_cond_init, ( vlc_cond_t * ) ); -VLC_EXPORT( void, __vlc_cond_destroy, ( const char *, int, vlc_cond_t * ) ); +VLC_EXPORT( void, vlc_mutex_destroy, ( vlc_mutex_t * ) ); +VLC_EXPORT( void, vlc_mutex_lock, ( vlc_mutex_t * ) ); +VLC_EXPORT( void, vlc_mutex_unlock, ( vlc_mutex_t * ) ); +VLC_EXPORT( int, vlc_cond_init, ( vlc_cond_t * ) ); +VLC_EXPORT( void, vlc_cond_destroy, ( vlc_cond_t * ) ); +VLC_EXPORT( void, vlc_cond_signal, (vlc_cond_t *) ); +VLC_EXPORT( void, vlc_cond_broadcast, (vlc_cond_t *) ); +VLC_EXPORT( void, vlc_cond_wait, (vlc_cond_t *, vlc_mutex_t *) ); +VLC_EXPORT( int, vlc_cond_timedwait, (vlc_cond_t *, vlc_mutex_t *, mtime_t) ); VLC_EXPORT( int, vlc_threadvar_create, (vlc_threadvar_t * , void (*) (void *) ) ); VLC_EXPORT( void, vlc_threadvar_delete, (vlc_threadvar_t *) ); -VLC_EXPORT( int, __vlc_thread_create, ( vlc_object_t *, const char *, int, const char *, void * ( * ) ( void * ), int, bool ) ); +VLC_EXPORT( int, __vlc_thread_create, ( vlc_object_t *, const char *, int, const char *, void * ( * ) ( vlc_object_t * ), int, bool ) ); VLC_EXPORT( int, __vlc_thread_set_priority, ( vlc_object_t *, const char *, int, int ) ); -VLC_EXPORT( void, __vlc_thread_ready, ( vlc_object_t * ) ); -VLC_EXPORT( void, __vlc_thread_join, ( vlc_object_t *, const char *, int ) ); - -/***************************************************************************** - * vlc_mutex_lock: lock a mutex - *****************************************************************************/ -#define vlc_mutex_lock( P_MUTEX ) \ - __vlc_mutex_lock( __FILE__, __LINE__, P_MUTEX ) - -#if defined(LIBVLC_USE_PTHREAD) -VLC_EXPORT(void, vlc_pthread_fatal, (const char *action, int error, const char *file, unsigned line)); - -# define VLC_THREAD_ASSERT( action ) \ - if (val) \ - vlc_pthread_fatal (action, val, psz_file, i_line) -#else -# define VLC_THREAD_ASSERT (void)0 +VLC_EXPORT( void, __vlc_thread_join, ( vlc_object_t * ) ); + +VLC_EXPORT( int, vlc_clone, (vlc_thread_t *, void * (*) (void *), void *, int) ); +VLC_EXPORT( void, vlc_cancel, (vlc_thread_t) ); +VLC_EXPORT( void, vlc_join, (vlc_thread_t, void **) ); +VLC_EXPORT (void, vlc_control_cancel, (int cmd, ...)); + +#ifndef LIBVLC_USE_PTHREAD_CANCEL +enum { + VLC_SAVE_CANCEL, + VLC_RESTORE_CANCEL, + VLC_TEST_CANCEL, + VLC_DO_CANCEL, + VLC_CLEANUP_PUSH, + VLC_CLEANUP_POP, +}; #endif -static inline void __vlc_mutex_lock( const char * psz_file, int i_line, - vlc_mutex_t * p_mutex ) -{ +#define vlc_thread_ready vlc_object_signal + #if defined(LIBVLC_USE_PTHREAD) # define vlc_assert_locked( m ) \ assert (pthread_mutex_lock (m) == EDEADLK) - int val = pthread_mutex_lock( p_mutex ); - VLC_THREAD_ASSERT ("locking mutex"); - -#elif defined( UNDER_CE ) - (void)psz_file; (void)i_line; - - EnterCriticalSection( &p_mutex->csection ); - -#elif defined( WIN32 ) - (void)psz_file; (void)i_line; - - WaitForSingleObject( *p_mutex, INFINITE ); - -#elif defined( SYS_BEOS ) - acquire_sem( p_mutex->lock ); - -#endif -} - -#ifndef vlc_assert_locked -# define vlc_assert_locked( m ) (void)0 +#else +# define vlc_assert_locked( m ) (void)m #endif -/***************************************************************************** - * vlc_mutex_unlock: unlock a mutex - *****************************************************************************/ -#define vlc_mutex_unlock( P_MUTEX ) \ - __vlc_mutex_unlock( __FILE__, __LINE__, P_MUTEX ) - -static inline void __vlc_mutex_unlock( const char * psz_file, int i_line, - vlc_mutex_t *p_mutex ) +/** + * Save the cancellation state and disable cancellation for the calling thread. + * This function must be called before entering a piece of code that is not + * cancellation-safe. + * @return Previous cancellation state (opaque value). + */ +static inline int vlc_savecancel (void) { -#if defined(LIBVLC_USE_PTHREAD) - int val = pthread_mutex_unlock( p_mutex ); - VLC_THREAD_ASSERT ("unlocking mutex"); - -#elif defined( UNDER_CE ) - (void)psz_file; (void)i_line; - - LeaveCriticalSection( &p_mutex->csection ); - -#elif defined( WIN32 ) - (void)psz_file; (void)i_line; - - ReleaseMutex( *p_mutex ); - -#elif defined( SYS_BEOS ) - release_sem( p_mutex->lock ); - + int state; +#if defined (LIBVLC_USE_PTHREAD_CANCEL) + (void) pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &state); +#else + vlc_control_cancel (VLC_SAVE_CANCEL, &state); #endif + return state; } -/***************************************************************************** - * vlc_mutex_destroy: destroy a mutex - *****************************************************************************/ -#define vlc_mutex_destroy( P_MUTEX ) \ - __vlc_mutex_destroy( __FILE__, __LINE__, P_MUTEX ) - -/***************************************************************************** - * vlc_cond_init: initialize a condition - *****************************************************************************/ -#define vlc_cond_init( P_THIS, P_COND ) \ - __vlc_cond_init( P_COND ) - -/***************************************************************************** - * vlc_cond_signal: start a thread on condition completion - *****************************************************************************/ -#define vlc_cond_signal( P_COND ) \ - __vlc_cond_signal( __FILE__, __LINE__, P_COND ) - -static inline void __vlc_cond_signal( const char * psz_file, int i_line, - vlc_cond_t *p_condvar ) +/** + * Restore the cancellation state for the calling thread. + * @param state previous state as returned by vlc_savecancel(). + * @return Nothing, always succeeds. + */ +static inline void vlc_restorecancel (int state) { -#if defined(LIBVLC_USE_PTHREAD) - int val = pthread_cond_signal( p_condvar ); - VLC_THREAD_ASSERT ("signaling condition variable"); - -#elif defined( UNDER_CE ) || defined( WIN32 ) - (void)psz_file; (void)i_line; - - /* Release one waiting thread if one is available. */ - /* For this trick to work properly, the vlc_cond_signal must be surrounded - * by a mutex. This will prevent another thread from stealing the signal */ - /* PulseEvent() only works if none of the waiting threads is suspended. - * This is particularily problematic under a debug session. - * as documented in http://support.microsoft.com/kb/q173260/ */ - PulseEvent( p_condvar->event ); - -#elif defined( SYS_BEOS ) - while( p_condvar->thread != -1 ) - { - thread_info info; - if( get_thread_info(p_condvar->thread, &info) == B_BAD_VALUE ) - return; - - if( info.state != B_THREAD_SUSPENDED ) - { - /* The waiting thread is not suspended so it could - * have been interrupted beetwen the unlock and the - * suspend_thread line. That is why we sleep a little - * before retesting p_condver->thread. */ - snooze( 10000 ); - } - else - { - /* Ok, we have to wake up that thread */ - resume_thread( p_condvar->thread ); - } - } - +#if defined (LIBVLC_USE_PTHREAD_CANCEL) + (void) pthread_setcancelstate (state, NULL); +#else + vlc_control_cancel (VLC_RESTORE_CANCEL, state); #endif } -/***************************************************************************** - * vlc_cond_wait: wait until condition completion - *****************************************************************************/ -#define vlc_cond_wait( P_COND, P_MUTEX ) \ - __vlc_cond_wait( __FILE__, __LINE__, P_COND, P_MUTEX ) - -static inline void __vlc_cond_wait( const char * psz_file, int i_line, - vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex ) +/** + * Issues an explicit deferred cancellation point. + * This has no effect if thread cancellation is disabled. + * This can be called when there is a rather slow non-sleeping operation. + */ +static inline void vlc_testcancel (void) { -#if defined(LIBVLC_USE_PTHREAD) - int val = pthread_cond_wait( p_condvar, p_mutex ); - VLC_THREAD_ASSERT ("waiting on condition"); - -#elif defined( UNDER_CE ) - p_condvar->i_waiting_threads++; - LeaveCriticalSection( &p_mutex->csection ); - WaitForSingleObject( p_condvar->event, INFINITE ); - p_condvar->i_waiting_threads--; - - /* Reacquire the mutex before returning. */ - vlc_mutex_lock( p_mutex ); - -#elif defined( WIN32 ) - (void)psz_file; (void)i_line; - - /* Increase our wait count */ - p_condvar->i_waiting_threads++; - SignalObjectAndWait( *p_mutex, p_condvar->event, INFINITE, FALSE ); - p_condvar->i_waiting_threads--; - - /* Reacquire the mutex before returning. */ - vlc_mutex_lock( p_mutex ); - -#elif defined( SYS_BEOS ) - /* The p_condvar->thread var is initialized before the unlock because - * it enables to identify when the thread is interrupted beetwen the - * unlock line and the suspend_thread line */ - p_condvar->thread = find_thread( NULL ); - vlc_mutex_unlock( p_mutex ); - suspend_thread( p_condvar->thread ); - p_condvar->thread = -1; - - vlc_mutex_lock( p_mutex ); - +#if defined (LIBVLC_USE_PTHREAD_CANCEL) + pthread_testcancel (); +#else + vlc_control_cancel (VLC_TEST_CANCEL); #endif } +#if defined (LIBVLC_USE_PTHREAD_CANCEL) +/** + * Registers a new procedure to run if the thread is cancelled (or otherwise + * exits prematurely). Any call to vlc_cleanup_push() must paired with a + * call to either vlc_cleanup_pop() or vlc_cleanup_run(). Branching into or out + * of the block between these two function calls is not allowed (read: it will + * likely crash the whole process). If multiple procedures are registered, + * they are handled in last-in first-out order. + * + * @param routine procedure to call if the thread ends + * @param arg argument for the procedure + */ +# define vlc_cleanup_push( routine, arg ) pthread_cleanup_push (routine, arg) -/***************************************************************************** - * vlc_cond_timedwait: wait until condition completion or expiration - ***************************************************************************** - * Returns 0 if object signaled, an error code in case of timeout or error. - *****************************************************************************/ -#define vlc_cond_timedwait( P_COND, P_MUTEX, DEADLINE ) \ - __vlc_cond_timedwait( __FILE__, __LINE__, P_COND, P_MUTEX, DEADLINE ) - -static inline int __vlc_cond_timedwait( const char * psz_file, int i_line, - vlc_cond_t *p_condvar, - vlc_mutex_t *p_mutex, - mtime_t deadline ) -{ -#if defined(LIBVLC_USE_PTHREAD) - lldiv_t d = lldiv( deadline, 1000000 ); - struct timespec ts = { d.quot, d.rem * 1000 }; - - int val = pthread_cond_timedwait (p_condvar, p_mutex, &ts); - if (val == ETIMEDOUT) - return ETIMEDOUT; /* this error is perfectly normal */ - VLC_THREAD_ASSERT ("timed-waiting on condition"); - -#elif defined( UNDER_CE ) - mtime_t delay_ms = (deadline - mdate())/1000; - DWORD result; - if( delay_ms < 0 ) - delay_ms = 0; - - p_condvar->i_waiting_threads++; - LeaveCriticalSection( &p_mutex->csection ); - result = WaitForSingleObject( p_condvar->event, delay_ms ); - p_condvar->i_waiting_threads--; - - /* Reacquire the mutex before returning. */ - vlc_mutex_lock( p_mutex ); - - if(result == WAIT_TIMEOUT) - return ETIMEDOUT; /* this error is perfectly normal */ - - (void)psz_file; (void)i_line; - -#elif defined( WIN32 ) - mtime_t delay_ms = (deadline - mdate())/1000; - DWORD result; - if( delay_ms < 0 ) - delay_ms = 0; - - /* Increase our wait count */ - p_condvar->i_waiting_threads++; - result = SignalObjectAndWait( *p_mutex, p_condvar->event, - delay_ms, FALSE ); - p_condvar->i_waiting_threads--; - - /* Reacquire the mutex before returning. */ - vlc_mutex_lock( p_mutex ); - if(result == WAIT_TIMEOUT) - return ETIMEDOUT; /* this error is perfectly normal */ - - (void)psz_file; (void)i_line; - -#elif defined( SYS_BEOS ) -# error Unimplemented +/** + * Removes a cleanup procedure that was previously registered with + * vlc_cleanup_push(). + */ +# define vlc_cleanup_pop( ) pthread_cleanup_pop (0) -#endif +/** + * Removes a cleanup procedure that was previously registered with + * vlc_cleanup_push(), and executes it. + */ +# define vlc_cleanup_run( ) pthread_cleanup_pop (1) +#else +typedef struct vlc_cleanup_t vlc_cleanup_t; - return 0; +struct vlc_cleanup_t +{ + vlc_cleanup_t *next; + void (*proc) (void *); + void *data; +}; + +/* This macros opens a code block on purpose. This is needed for multiple + * calls within a single function. This also prevent Win32 developpers from + * writing code that would break on POSIX (POSIX opens a block as well). */ +# define vlc_cleanup_push( routine, arg ) \ + do { \ + vlc_cleanup_t vlc_cleanup_data = { NULL, routine, arg, }; \ + vlc_control_cancel (VLC_CLEANUP_PUSH, &vlc_cleanup_data) + +# define vlc_cleanup_pop( ) \ + vlc_control_cancel (VLC_CLEANUP_POP); \ + } while (0) + +# define vlc_cleanup_run( ) \ + vlc_control_cancel (VLC_CLEANUP_POP); \ + vlc_cleanup_data.proc (vlc_cleanup_data.data); \ + } while (0) + +#endif /* LIBVLC_USE_PTHREAD_CANCEL */ + +static inline void vlc_cleanup_lock (void *lock) +{ + vlc_mutex_unlock ((vlc_mutex_t *)lock); } - -/***************************************************************************** - * vlc_cond_destroy: destroy a condition - *****************************************************************************/ -#define vlc_cond_destroy( P_COND ) \ - __vlc_cond_destroy( __FILE__, __LINE__, P_COND ) +#define mutex_cleanup_push( lock ) vlc_cleanup_push (vlc_cleanup_lock, lock) /***************************************************************************** * vlc_threadvar_set: create: set the value of a thread-local variable @@ -445,9 +287,6 @@ static inline int vlc_threadvar_set( vlc_threadvar_t * p_tls, void *p_value ) #if defined(LIBVLC_USE_PTHREAD) i_ret = pthread_setspecific( *p_tls, p_value ); -#elif defined( SYS_BEOS ) - i_ret = EINVAL; - #elif defined( UNDER_CE ) || defined( WIN32 ) i_ret = TlsSetValue( *p_tls, p_value ) ? EINVAL : 0; @@ -466,9 +305,6 @@ static inline void* vlc_threadvar_get( vlc_threadvar_t * p_tls ) #if defined(LIBVLC_USE_PTHREAD) p_ret = pthread_getspecific( *p_tls ); -#elif defined( SYS_BEOS ) - p_ret = NULL; - #elif defined( UNDER_CE ) || defined( WIN32 ) p_ret = TlsGetValue( *p_tls ); @@ -563,11 +399,36 @@ static inline int vlc_spin_init (vlc_spinlock_t *spin) # define vlc_spin_destroy vlc_mutex_destroy #endif +/** + * Issues a full memory barrier. + */ +#if defined (__APPLE__) +# include /* OSMemoryBarrier() */ +#endif +static inline void barrier (void) +{ +#if defined (__GNUC__) && (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) + __sync_synchronize (); +#elif defined(__APPLE__) + OSMemoryBarrier (); +#elif defined(__powerpc__) + asm volatile ("sync":::"memory"); +#elif defined(__i386__) + asm volatile ("mfence":::"memory"); +#else + vlc_spinlock_t spin; + vlc_spin_init (&spin); + vlc_spin_lock (&spin); + vlc_spin_unlock (&spin); + vlc_spin_destroy (&spin); +#endif +} + /***************************************************************************** * vlc_thread_create: create a thread *****************************************************************************/ #define vlc_thread_create( P_THIS, PSZ_NAME, FUNC, PRIORITY, WAIT ) \ - __vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, (void * ( * ) ( void * ))FUNC, PRIORITY, WAIT ) + __vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, FUNC, PRIORITY, WAIT ) /***************************************************************************** * vlc_thread_set_priority: set the priority of the calling thread @@ -575,16 +436,10 @@ static inline int vlc_spin_init (vlc_spinlock_t *spin) #define vlc_thread_set_priority( P_THIS, PRIORITY ) \ __vlc_thread_set_priority( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PRIORITY ) -/***************************************************************************** - * vlc_thread_ready: tell the parent thread we were successfully spawned - *****************************************************************************/ -#define vlc_thread_ready( P_THIS ) \ - __vlc_thread_ready( VLC_OBJECT(P_THIS) ) - /***************************************************************************** * vlc_thread_join: wait until a thread exits *****************************************************************************/ #define vlc_thread_join( P_THIS ) \ - __vlc_thread_join( VLC_OBJECT(P_THIS), __FILE__, __LINE__ ) + __vlc_thread_join( VLC_OBJECT(P_THIS) ) #endif /* !_VLC_THREADS_H */