Mercurial > sdl-ios-xcode
diff include/SDL_mutex.h @ 0:74212992fb08
Initial revision
author | Sam Lantinga <slouken@lokigames.com> |
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date | Thu, 26 Apr 2001 16:45:43 +0000 |
parents | |
children | b8688cfdc232 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/include/SDL_mutex.h Thu Apr 26 16:45:43 2001 +0000 @@ -0,0 +1,163 @@ +/* + SDL - Simple DirectMedia Layer + Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + + Sam Lantinga + slouken@devolution.com +*/ + +#ifdef SAVE_RCSID +static char rcsid = + "@(#) $Id$"; +#endif + +#ifndef _SDL_mutex_h +#define _SDL_mutex_h + +/* Functions to provide thread synchronization primitives + + These are independent of the other SDL routines. +*/ + +#include "SDL_main.h" +#include "SDL_types.h" + +#include "begin_code.h" +/* Set up for C function definitions, even when using C++ */ +#ifdef __cplusplus +extern "C" { +#endif + +/* Synchronization functions which can time out return this value + if they time out. +*/ +#define SDL_MUTEX_TIMEDOUT 1 + +/* This is the timeout value which corresponds to never time out */ +#define SDL_MUTEX_MAXWAIT (~(Uint32)0) + + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +/* Mutex functions */ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ + +/* The SDL mutex structure, defined in SDL_mutex.c */ +struct SDL_mutex; +typedef struct SDL_mutex SDL_mutex; + +/* Create a mutex, initialized unlocked */ +extern DECLSPEC SDL_mutex * SDL_CreateMutex(void); + +/* Lock the mutex (Returns 0, or -1 on error) */ +#define SDL_LockMutex(m) SDL_mutexP(m) +extern DECLSPEC int SDL_mutexP(SDL_mutex *mutex); + +/* Unlock the mutex (Returns 0, or -1 on error) */ +#define SDL_UnlockMutex(m) SDL_mutexV(m) +extern DECLSPEC int SDL_mutexV(SDL_mutex *mutex); + +/* Destroy a mutex */ +extern DECLSPEC void SDL_DestroyMutex(SDL_mutex *mutex); + + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +/* Semaphore functions */ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ + +/* The SDL semaphore structure, defined in SDL_sem.c */ +struct SDL_semaphore; +typedef struct SDL_semaphore SDL_sem; + +/* Create a semaphore, initialized with value, returns NULL on failure. */ +extern DECLSPEC SDL_sem * SDL_CreateSemaphore(Uint32 initial_value); + +/* Destroy a semaphore */ +extern DECLSPEC void SDL_DestroySemaphore(SDL_sem *sem); + +/* This function suspends the calling thread until the semaphore pointed + * to by sem has a positive count. It then atomically decreases the semaphore + * count. + */ +extern DECLSPEC int SDL_SemWait(SDL_sem *sem); + +/* Non-blocking variant of SDL_SemWait(), returns 0 if the wait succeeds, + SDL_MUTEX_TIMEDOUT if the wait would block, and -1 on error. +*/ +extern DECLSPEC int SDL_SemTryWait(SDL_sem *sem); + +/* Variant of SDL_SemWait() with a timeout in milliseconds, returns 0 if + the wait succeeds, SDL_MUTEX_TIMEDOUT if the wait does not succeed in + the allotted time, and -1 on error. + On some platforms this function is implemented by looping with a delay + of 1 ms, and so should be avoided if possible. +*/ +extern DECLSPEC int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 ms); + +/* Atomically increases the semaphore's count (not blocking), returns 0, + or -1 on error. + */ +extern DECLSPEC int SDL_SemPost(SDL_sem *sem); + +/* Returns the current count of the semaphore */ +extern DECLSPEC Uint32 SDL_SemValue(SDL_sem *sem); + + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +/* Condition variable functions */ +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ + +/* The SDL condition variable structure, defined in SDL_cond.c */ +struct SDL_cond; +typedef struct SDL_cond SDL_cond; + +/* Create a condition variable */ +extern DECLSPEC SDL_cond * SDL_CreateCond(void); + +/* Destroy a condition variable */ +extern DECLSPEC void SDL_DestroyCond(SDL_cond *cond); + +/* Restart one of the threads that are waiting on the condition variable, + returns 0 or -1 on error. + */ +extern DECLSPEC int SDL_CondSignal(SDL_cond *cond); + +/* Restart all threads that are waiting on the condition variable, + returns 0 or -1 on error. + */ +extern DECLSPEC int SDL_CondBroadcast(SDL_cond *cond); + +/* Wait on the condition variable, unlocking the provided mutex. + The mutex must be locked before entering this function! + Returns 0 when it is signaled, or -1 on error. + */ +extern DECLSPEC int SDL_CondWait(SDL_cond *cond, SDL_mutex *mut); + +/* Waits for at most 'ms' milliseconds, and returns 0 if the condition + variable is signaled, SDL_MUTEX_TIMEDOUT if the condition is not + signaled in the allotted time, and -1 on error. + On some platforms this function is implemented by looping with a delay + of 1 ms, and so should be avoided if possible. +*/ +extern DECLSPEC int SDL_CondWaitTimeout(SDL_cond *cond, SDL_mutex *mutex, Uint32 ms); + +/* Ends C function definitions when using C++ */ +#ifdef __cplusplus +} +#endif +#include "close_code.h" + +#endif /* _SDL_mutex_h */