/***************************************************************************** * vlc_threads.h : threads implementation for the VideoLAN client * This header provides portable declarations for mutexes & conditions ***************************************************************************** * Copyright (C) 1999, 2002 the VideoLAN team * Copyright © 2007-2008 Rémi Denis-Courmont * * Authors: Jean-Marc Dressler * Samuel Hocevar * Gildas Bazin * Christophe Massiot * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ #ifndef VLC_THREADS_H_ #define VLC_THREADS_H_ /** * \file * This file defines structures and functions for handling threads in vlc * */ #if defined( UNDER_CE ) #elif defined( WIN32 ) # include /* Win32 API */ #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 /* _POSIX_SPIN_LOCKS */ # include # include #endif /***************************************************************************** * Constants *****************************************************************************/ /* Thread priorities */ #ifdef __APPLE__ # 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 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 */ # define VLC_THREAD_PRIORITY_LOW 0 # define VLC_THREAD_PRIORITY_INPUT \ THREAD_PRIORITY_ABOVE_NORMAL # define VLC_THREAD_PRIORITY_AUDIO \ THREAD_PRIORITY_HIGHEST # define VLC_THREAD_PRIORITY_VIDEO 0 # define VLC_THREAD_PRIORITY_OUTPUT \ THREAD_PRIORITY_ABOVE_NORMAL # define VLC_THREAD_PRIORITY_HIGHEST \ THREAD_PRIORITY_TIME_CRITICAL #else # define VLC_THREAD_PRIORITY_LOW 0 # define VLC_THREAD_PRIORITY_INPUT 0 # define VLC_THREAD_PRIORITY_AUDIO 0 # define VLC_THREAD_PRIORITY_VIDEO 0 # define VLC_THREAD_PRIORITY_OUTPUT 0 # define VLC_THREAD_PRIORITY_HIGHEST 0 #endif /***************************************************************************** * Type definitions *****************************************************************************/ #if defined (LIBVLC_USE_PTHREAD) typedef pthread_t vlc_thread_t; typedef pthread_mutex_t vlc_mutex_t; #define VLC_STATIC_MUTEX PTHREAD_MUTEX_INITIALIZER typedef pthread_cond_t vlc_cond_t; #define VLC_STATIC_COND PTHREAD_COND_INITIALIZER typedef sem_t vlc_sem_t; typedef pthread_rwlock_t vlc_rwlock_t; typedef pthread_key_t vlc_threadvar_t; typedef struct vlc_timer *vlc_timer_t; #elif defined( WIN32 ) #if !defined( UNDER_CE ) typedef HANDLE vlc_thread_t; #else typedef struct { HANDLE handle; HANDLE cancel_event; } *vlc_thread_t; #endif typedef struct { bool dynamic; union { struct { bool locked; unsigned long contention; }; CRITICAL_SECTION mutex; }; } vlc_mutex_t; #define VLC_STATIC_MUTEX { false, { { false, 0 } } } typedef struct { HANDLE handle; unsigned clock; } vlc_cond_t; typedef HANDLE vlc_sem_t; typedef struct { vlc_mutex_t mutex; vlc_cond_t read_wait; vlc_cond_t write_wait; unsigned long readers; unsigned long writers; DWORD writer; } vlc_rwlock_t; typedef DWORD vlc_threadvar_t; typedef struct vlc_timer *vlc_timer_t; #endif #if defined( WIN32 ) && !defined ETIMEDOUT # define ETIMEDOUT 10060 /* This is the value in winsock.h. */ #endif /***************************************************************************** * Function definitions *****************************************************************************/ VLC_EXPORT( void, vlc_mutex_init, ( vlc_mutex_t * ) ); VLC_EXPORT( void, vlc_mutex_init_recursive, ( vlc_mutex_t * ) ); VLC_EXPORT( void, vlc_mutex_destroy, ( vlc_mutex_t * ) ); VLC_EXPORT( void, vlc_mutex_lock, ( vlc_mutex_t * ) ); VLC_EXPORT( int, vlc_mutex_trylock, ( vlc_mutex_t * ) LIBVLC_USED ); VLC_EXPORT( void, vlc_mutex_unlock, ( vlc_mutex_t * ) ); VLC_EXPORT( void, vlc_cond_init, ( vlc_cond_t * ) ); VLC_EXPORT( void, vlc_cond_init_daytime, ( 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( void, vlc_sem_init, (vlc_sem_t *, unsigned) ); VLC_EXPORT( void, vlc_sem_destroy, (vlc_sem_t *) ); VLC_EXPORT( int, vlc_sem_post, (vlc_sem_t *) ); VLC_EXPORT( void, vlc_sem_wait, (vlc_sem_t *) ); VLC_EXPORT( void, vlc_rwlock_init, (vlc_rwlock_t *) ); VLC_EXPORT( void, vlc_rwlock_destroy, (vlc_rwlock_t *) ); VLC_EXPORT( void, vlc_rwlock_rdlock, (vlc_rwlock_t *) ); VLC_EXPORT( void, vlc_rwlock_wrlock, (vlc_rwlock_t *) ); VLC_EXPORT( void, vlc_rwlock_unlock, (vlc_rwlock_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_threadvar_set, (vlc_threadvar_t, void *) ); VLC_EXPORT( void *, vlc_threadvar_get, (vlc_threadvar_t) ); VLC_EXPORT( int, vlc_thread_create, ( vlc_object_t *, const char *, int, const char *, void * ( * ) ( vlc_object_t * ), int ) LIBVLC_USED ); VLC_EXPORT( int, vlc_thread_set_priority, ( vlc_object_t *, const char *, int, int ) ); VLC_EXPORT( void, vlc_thread_join, ( vlc_object_t * ) ); VLC_EXPORT( int, vlc_clone, (vlc_thread_t *, void * (*) (void *), void *, int) LIBVLC_USED ); 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, ...)); VLC_EXPORT( int, vlc_timer_create, (vlc_timer_t *, void (*) (void *), void *) LIBVLC_USED ); VLC_EXPORT( void, vlc_timer_destroy, (vlc_timer_t) ); VLC_EXPORT( void, vlc_timer_schedule, (vlc_timer_t, bool, mtime_t, mtime_t) ); VLC_EXPORT( unsigned, vlc_timer_getoverrun, (vlc_timer_t) LIBVLC_USED ); #ifndef LIBVLC_USE_PTHREAD_CANCEL enum { VLC_CLEANUP_PUSH, VLC_CLEANUP_POP, }; #endif VLC_EXPORT( int, vlc_savecancel, (void) ); VLC_EXPORT( void, vlc_restorecancel, (int state) ); VLC_EXPORT( void, vlc_testcancel, (void) ); #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) /** * Removes a cleanup procedure that was previously registered with * vlc_cleanup_push(). */ # define vlc_cleanup_pop( ) pthread_cleanup_pop (0) /** * 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; 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 developers 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); } #define mutex_cleanup_push( lock ) vlc_cleanup_push (vlc_cleanup_lock, lock) # if defined (_POSIX_SPIN_LOCKS) && ((_POSIX_SPIN_LOCKS - 0) > 0) typedef pthread_spinlock_t vlc_spinlock_t; /** * Initializes a spinlock. */ static inline void vlc_spin_init (vlc_spinlock_t *spin) { if (pthread_spin_init (spin, PTHREAD_PROCESS_PRIVATE)) abort (); } /** * Acquires a spinlock. */ static inline void vlc_spin_lock (vlc_spinlock_t *spin) { pthread_spin_lock (spin); } /** * Releases a spinlock. */ static inline void vlc_spin_unlock (vlc_spinlock_t *spin) { pthread_spin_unlock (spin); } /** * Deinitializes a spinlock. */ static inline void vlc_spin_destroy (vlc_spinlock_t *spin) { pthread_spin_destroy (spin); } #elif defined (WIN32) && !defined (UNDER_CE) typedef CRITICAL_SECTION vlc_spinlock_t; /** * Initializes a spinlock. */ static inline void vlc_spin_init (vlc_spinlock_t *spin) { if (!InitializeCriticalSectionAndSpinCount(spin, 4000)) abort (); } /** * Acquires a spinlock. */ static inline void vlc_spin_lock (vlc_spinlock_t *spin) { EnterCriticalSection(spin); } /** * Releases a spinlock. */ static inline void vlc_spin_unlock (vlc_spinlock_t *spin) { LeaveCriticalSection(spin); } /** * Deinitializes a spinlock. */ static inline void vlc_spin_destroy (vlc_spinlock_t *spin) { DeleteCriticalSection(spin); } #else /* Fallback to plain mutexes if spinlocks are not available */ typedef vlc_mutex_t vlc_spinlock_t; static inline void vlc_spin_init (vlc_spinlock_t *spin) { vlc_mutex_init (spin); } # define vlc_spin_lock vlc_mutex_lock # define vlc_spin_unlock vlc_mutex_unlock # 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__) && !defined (__APPLE__) && \ ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)) __sync_synchronize (); #elif defined(__APPLE__) OSMemoryBarrier (); #elif defined(__powerpc__) asm volatile ("sync":::"memory"); #elif 0 // defined(__i386__) /* Requires SSE2 support */ 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 ) \ vlc_thread_create( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PSZ_NAME, FUNC, PRIORITY ) /***************************************************************************** * vlc_thread_set_priority: set the priority of the calling thread *****************************************************************************/ #define vlc_thread_set_priority( P_THIS, PRIORITY ) \ vlc_thread_set_priority( VLC_OBJECT(P_THIS), __FILE__, __LINE__, PRIORITY ) /***************************************************************************** * vlc_thread_join: wait until a thread exits *****************************************************************************/ #define vlc_thread_join( P_THIS ) \ vlc_thread_join( VLC_OBJECT(P_THIS) ) #ifdef __cplusplus /** * Helper C++ class to lock a mutex. * The mutex is locked when the object is created, and unlocked when the object * is destroyed. */ class vlc_mutex_locker { private: vlc_mutex_t *lock; public: vlc_mutex_locker (vlc_mutex_t *m) : lock (m) { vlc_mutex_lock (lock); } ~vlc_mutex_locker (void) { vlc_mutex_unlock (lock); } }; #endif enum { VLC_XLIB_MUTEX, /* Insert new entry HERE */ VLC_MAX_MUTEX }; VLC_EXPORT( void, vlc_global_mutex, ( unsigned, bool ) ); #define vlc_global_lock( n ) vlc_global_mutex( n, true ) #define vlc_global_unlock( n ) vlc_global_mutex( n, false ) #endif /* !_VLC_THREADS_H */