src/thread/linux/SDL_syssem.c
author Sam Lantinga <slouken@lokigames.com>
Sun, 08 Jul 2001 09:00:06 +0000
changeset 94 ae6e6b73333f
parent 18 d9e3595b63d5
child 252 e8157fcb3114
permissions -rw-r--r--
Cleaned up the OpenBSD port, thanks to Peter Valchev
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/*
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    SDL - Simple DirectMedia Layer
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    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
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    This library is free software; you can redistribute it and/or
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    modify it under the terms of the GNU Library General Public
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    License as published by the Free Software Foundation; either
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    version 2 of the License, or (at your option) any later version.
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    This library is distributed in the hope that it will be useful,
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    but WITHOUT ANY WARRANTY; without even the implied warranty of
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    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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    Library General Public License for more details.
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    You should have received a copy of the GNU Library General Public
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    License along with this library; if not, write to the Free
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    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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    Sam Lantinga
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    slouken@devolution.com
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*/
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#ifdef SAVE_RCSID
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static char rcsid =
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 "@(#) $Id$";
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#endif
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#include <stdlib.h>
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#include "SDL_error.h"
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#include "SDL_thread.h"
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#include "SDL_timer.h"
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#ifdef linux
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/* Look to see if glibc is available, and if so, what version */
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#include <features.h>
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#if (__GLIBC__ == 2) && (__GLIBC_MINOR__ == 0)
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#warning Working around a bug in glibc 2.0 pthreads
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#undef SDL_USE_PTHREADS
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/* The bug is actually a problem where threads are suspended, but don't
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   wake up when the thread manager sends them a signal.  This is a problem
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   with thread creation too, but it happens less often. :-/
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   We avoid this by using System V IPC for semaphores.
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 */
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#endif /* glibc 2.0 */
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#endif /* linux */
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#ifdef SDL_USE_PTHREADS
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#ifdef SDL_NO_PTHREAD_SEMAPHORES
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#include "generic/SDL_syssem.c"
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#else
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>			/* For getpid() */
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#include <pthread.h>
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#include <semaphore.h>
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/* Wrapper around POSIX 1003.1b semaphores */
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#ifdef MACOSX
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#define USE_NAMED_SEMAPHORES
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/* Broken sem_getvalue() in MacOS X Public Beta */
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#define BROKEN_SEMGETVALUE
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#endif /* MACOSX */
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struct SDL_semaphore {
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	sem_t *sem;
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#ifndef USE_NAMED_SEMAPHORES
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	sem_t sem_data;
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#endif
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#ifdef BROKEN_SEMGETVALUE
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	/* This is a little hack for MacOS X -
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	   It's not thread-safe, but it's better than nothing
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	 */
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	int sem_value;
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#endif
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};
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/* Create a semaphore, initialized with value */
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SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
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{
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	SDL_sem *sem = (SDL_sem *) malloc(sizeof(SDL_sem));
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	if ( sem ) {
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#ifdef USE_NAMED_SEMAPHORES
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		static int semnum = 0;
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		char name[32];
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		sprintf(name, "/SDL_sem-%d-%4.4d", getpid(), semnum++);
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		sem->sem = sem_open(name, O_CREAT, 0600, initial_value);
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		if ( sem->sem == (sem_t *)SEM_FAILED ) {
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			SDL_SetError("sem_open(%s) failed", name);
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			free(sem);
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			sem = NULL;
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		} else {
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			sem_unlink(name);
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		}
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#else
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		if ( sem_init(&sem->sem_data, 0, initial_value) < 0 ) {
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			SDL_SetError("sem_init() failed");
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			free(sem);
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			sem = NULL;
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		} else {
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			sem->sem = &sem->sem_data;
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		}
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#endif /* USE_NAMED_SEMAPHORES */
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#ifdef BROKEN_SEMGETVALUE
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		if ( sem ) {
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			sem->sem_value = initial_value;
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		}
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#endif /* BROKEN_SEMGETVALUE */
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	} else {
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		SDL_OutOfMemory();
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	}
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	return sem;
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}
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void SDL_DestroySemaphore(SDL_sem *sem)
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{
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	if ( sem ) {
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#ifdef USE_NAMED_SEMAPHORES
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		sem_close(sem->sem);
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#else
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		sem_destroy(sem->sem);
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#endif
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		free(sem);
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	}
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}
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int SDL_SemTryWait(SDL_sem *sem)
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{
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	int retval;
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	if ( ! sem ) {
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		SDL_SetError("Passed a NULL semaphore");
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		return -1;
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	}
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	retval = SDL_MUTEX_TIMEDOUT;
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	if ( sem_trywait(sem->sem) == 0 ) {
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#ifdef BROKEN_SEMGETVALUE
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		--sem->sem_value;
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#endif
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		retval = 0;
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	}
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	return retval;
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}
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int SDL_SemWait(SDL_sem *sem)
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{
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	int retval;
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	if ( ! sem ) {
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		SDL_SetError("Passed a NULL semaphore");
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		return -1;
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	}
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#ifdef BROKEN_SEMGETVALUE
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	--sem->sem_value;
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#endif
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	retval = sem_wait(sem->sem);
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	if ( retval < 0 ) {
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		SDL_SetError("sem_wait() failed");
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	}
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	return retval;
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}
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int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
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{
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	int retval;
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	if ( ! sem ) {
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		SDL_SetError("Passed a NULL semaphore");
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		return -1;
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	}
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	/* Try the easy cases first */
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	if ( timeout == 0 ) {
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		return SDL_SemTryWait(sem);
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	}
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	if ( timeout == SDL_MUTEX_MAXWAIT ) {
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		return SDL_SemWait(sem);
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	}
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	/* Ack!  We have to busy wait... */
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	timeout += SDL_GetTicks();
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	do {
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		retval = SDL_SemTryWait(sem);
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		if ( retval == 0 ) {
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			break;
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		}
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		SDL_Delay(1);
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	} while ( SDL_GetTicks() < timeout );
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	return retval;
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}
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Uint32 SDL_SemValue(SDL_sem *sem)
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{
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	int ret = 0;
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	if ( sem ) {
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#ifdef BROKEN_SEMGETVALUE
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		ret = sem->sem_value;
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#else
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		sem_getvalue(sem->sem, &ret);
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#endif
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		if ( ret < 0 ) {
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			ret = 0;
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		}
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	}
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	return (Uint32)ret;
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}
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int SDL_SemPost(SDL_sem *sem)
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{
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	int retval;
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	if ( ! sem ) {
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		SDL_SetError("Passed a NULL semaphore");
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		return -1;
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	}
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#ifdef BROKEN_SEMGETVALUE
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	++sem->sem_value;
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#endif
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	retval = sem_post(sem->sem);
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	if ( retval < 0 ) {
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		SDL_SetError("sem_post() failed");
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	}
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	return retval;
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}
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#endif /* NO_PTHREAD_SEMAPHORES */
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#else /* System V IPC implementation */
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/ipc.h>
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#include <sys/sem.h>
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#include <errno.h>
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#include "SDL_error.h"
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#include "SDL_thread.h"
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struct SDL_semaphore {
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	int id;
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};
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/* Not defined by many operating systems, use configure to detect */
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#if !defined(HAVE_SEMUN)
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union semun {
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	int val;
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	struct semid_ds *buf;
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	ushort *array;
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};
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#endif
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static struct sembuf op_trywait[2] = {
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	{ 0, -1, (IPC_NOWAIT|SEM_UNDO) } /* Decrement semaphore, no block */
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};
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static struct sembuf op_wait[2] = {
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	{ 0, -1, SEM_UNDO }		/* Decrement semaphore */
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};
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static struct sembuf op_post[1] = {
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	{ 0, 1, (IPC_NOWAIT|SEM_UNDO) }	/* Increment semaphore */
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};
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/* Create a blockable semaphore */
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SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
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{
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	extern int _creating_thread_lock;	/* SDL_threads.c */
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	SDL_sem *sem;
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	union semun init;
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	key_t key;
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	sem = (SDL_sem *)malloc(sizeof(*sem));
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	if ( sem == NULL ) {
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		SDL_OutOfMemory();
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		return(NULL);
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	}
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	/* This flag is true if we are creating the thread manager sem,
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	   which is never freed.  This allows us to reuse the same sem.
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	*/
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	if ( _creating_thread_lock ) {
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		key = 'S'+'D'+'L';
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	} else {
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		key = IPC_PRIVATE;
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	}
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	/* Keep trying to create sem while we don't own the requested key */
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	do {
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		if ( key != IPC_PRIVATE ) {
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			++key;
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		}
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		sem->id = semget(key, 1, (0600|IPC_CREAT));
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	} while ((sem->id < 0) && (key != IPC_PRIVATE) && (errno == EACCES));
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	/* Report the error if we eventually failed */
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	if ( sem->id < 0 ) {
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		SDL_SetError("Couldn't create semaphore");
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		free(sem);
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		return(NULL);
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	}
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	init.val = initial_value;	/* Initialize semaphore */
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	semctl(sem->id, 0, SETVAL, init);
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	return(sem);
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}
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void SDL_DestroySemaphore(SDL_sem *sem)
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{
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	if ( sem ) {
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#ifdef _SGI_SOURCE
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		semctl(sem->id, 0, IPC_RMID);
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#else
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		union semun dummy;
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		dummy.val = 0;
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		semctl(sem->id, 0, IPC_RMID, dummy);
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#endif
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		free(sem);
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   323
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   324
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   325
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   326
int SDL_SemTryWait(SDL_sem *sem)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   327
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   328
	int retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   329
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   330
	if ( ! sem ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   331
		SDL_SetError("Passed a NULL semaphore");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   332
		return -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   333
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   334
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   335
	retval = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   336
  tryagain:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   337
	if ( semop(sem->id, op_trywait, 1) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   338
		if ( errno == EINTR ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   339
			goto tryagain;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   340
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   341
		retval = SDL_MUTEX_TIMEDOUT;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   342
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   343
	return retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   344
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   345
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   346
int SDL_SemWait(SDL_sem *sem)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   347
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   348
	int retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   349
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   350
	if ( ! sem ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   351
		SDL_SetError("Passed a NULL semaphore");
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   352
		return -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   353
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   354
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   355
	retval = 0;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   356
  tryagain:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   357
	if ( semop(sem->id, op_wait, 1) < 0 ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   358
		if ( errno == EINTR ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   359
			goto tryagain;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   360
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   361
		SDL_SetError("Semaphore operation error");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   362
		retval = -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   363
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   364
	return retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   365
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   366
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   367
int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   368
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   369
	int retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   370
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   371
	if ( ! sem ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   372
		SDL_SetError("Passed a NULL semaphore");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   373
		return -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   374
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   375
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   376
	/* Try the easy cases first */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   377
	if ( timeout == 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   378
		return SDL_SemTryWait(sem);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   379
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   380
	if ( timeout == SDL_MUTEX_MAXWAIT ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   381
		return SDL_SemWait(sem);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   382
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   383
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   384
	/* Ack!  We have to busy wait... */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   385
	timeout += SDL_GetTicks();
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   386
	do {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   387
		retval = SDL_SemTryWait(sem);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   388
		if ( retval == 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   389
			break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   390
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   391
		SDL_Delay(1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   392
	} while ( SDL_GetTicks() < timeout );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   393
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   394
	return retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   395
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   396
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   397
Uint32 SDL_SemValue(SDL_sem *sem)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   398
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   399
	int semval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   400
	Uint32 value;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   401
	
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   402
	value = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   403
	if ( sem ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   404
	  tryagain:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   405
#ifdef _SGI_SOURCE
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   406
		semval = semctl(sem->id, 0, GETVAL);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   407
#else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   408
		{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   409
		union semun arg;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   410
		arg.val = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   411
		semval = semctl(sem->id, 0, GETVAL, arg);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   412
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   413
#endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   414
		if ( semval < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   415
			if ( errno == EINTR ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   416
				goto tryagain;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   417
			}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   418
		} else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   419
			value = (Uint32)semval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   420
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   421
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   422
	return value;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   423
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   424
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   425
int SDL_SemPost(SDL_sem *sem)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   426
{
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   427
	int retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   428
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   429
	if ( ! sem ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   430
		SDL_SetError("Passed a NULL semaphore");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   431
		return -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   432
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   433
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   434
	retval = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   435
  tryagain:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   436
	if ( semop(sem->id, op_post, 1) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   437
		if ( errno == EINTR ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   438
			goto tryagain;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   439
		}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   440
		SDL_SetError("Semaphore operation error");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   441
		retval = -1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   442
	}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   443
	return retval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   444
}
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   445
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
   446
#endif /* SDL_USE_PTHREADS */