diff include/SDL_mutex.h @ 0:74212992fb08

Initial revision
author Sam Lantinga <slouken@lokigames.com>
date Thu, 26 Apr 2001 16:45:43 +0000
parents
children b8688cfdc232
line wrap: on
line diff
--- /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 */