I've attached the semaphore.h files of my systems, and the libSDL source
file that uses sem_timedwait.
Looks like _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600 would be
the right switch according to http://linux.die.net/man/3/sem_timedwait .
Should it use the same "../generic/SDL_syssem.c" like it does for macosx
when _POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600 isnt true?
Because You cant just replace SDL_SemWaitTimeout(), the structure of
SDL_semaphore differ.
> On Monday, January 09, 2012 at 12:17 PM, Tobias Leich wrote:
>
>> I get the same issue on my NetBSD 5.1.3 i386. Are all BSD's affected?
>> Can somebody approve?
> As I understand it, sem_timedwait isn't a part of BSD, so you're not likely
> to
> find it on any *BSD or Mac OS X or Solaris (though newer versions may have
> it).
> There ought to be a #define around code which uses it.
>
> -- c
>
/* $NetBSD: semaphore.h,v 1.3 2008/04/28 20:22:54 martin Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SEMAPHORE_H_
#define _SEMAPHORE_H_
/* POSIX 1003.1b semaphores */
struct _sem_st;
typedef>struct _sem_st *sem_t;
#define>SEM_FAILED<---->((sem_t *)0)
#define>SEM_VALUE_MAX<->(~0U)
#include <sys/cdefs.h>
/* $NetBSD: semaphore.h,v 1.3 2008/04/28 20:22:54 martin Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SEMAPHORE_H_
#define _SEMAPHORE_H_
/* POSIX 1003.1b semaphores */
struct _sem_st;
typedef>struct _sem_st *sem_t;
#define>SEM_FAILED<---->((sem_t *)0)
#define>SEM_VALUE_MAX<->(~0U)
#include <sys/cdefs.h>
__BEGIN_DECLS
int<---> sem_close(sem_t *);
int<---> sem_destroy(sem_t *);
int<---> sem_getvalue(sem_t * __restrict, int * __restrict);
int<---> sem_init(sem_t *, int, unsigned int);
int<---> sem_post(sem_t *);
int<---> sem_trywait(sem_t *);
int<---> sem_unlink(const char *);
int<---> sem_wait(sem_t *);
sem_t<->*sem_open(const char *, int, ...);
__END_DECLS
#endif /* !_SEMAPHORE_H_ */
/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _SEMAPHORE_H
#define _SEMAPHORE_H<-->1
#include <features.h>
#include <sys/types.h>
#ifdef __USE_XOPEN2K
# define __need_timespec
# include <time.h>
#endif
/* Get the definition for sem_t. */
#include <bits/semaphore.h>
__BEGIN_DECLS
/* Initialize semaphore object SEM to VALUE. If PSHARED then share it
with other processes. */
extern int sem_init (sem_t *__sem, int __pshared, unsigned int __value)
__THROW;
/* Free resources associated with semaphore object SEM. */
extern int sem_destroy (sem_t *__sem) __THROW;
/* Open a named semaphore NAME with open flags OFLAG. */
extern sem_t *sem_open (__const char *__name, int __oflag, ...) __THROW;
/* Close descriptor for named semaphore SEM. */
extern int sem_close (sem_t *__sem) __THROW;
/* Remove named semaphore NAME. */
extern int sem_unlink (__const char *__name) __THROW;
/* Wait for SEM being posted.
This function is a cancellation point and therefore not marked with
__THROW. */
extern int sem_wait (sem_t *__sem);
#ifdef __USE_XOPEN2K
/* Similar to `sem_wait' but wait only until ABSTIME.
This function is a cancellation point and therefore not marked with
__THROW. */
extern int sem_timedwait (sem_t *__restrict __sem,
<------><------><------> __const struct timespec *__restrict __abstime);
#endif
/* Test whether SEM is posted. */
extern int sem_trywait (sem_t *__sem) __THROW;
/* Post SEM. */
extern int sem_post (sem_t *__sem) __THROW;
/* Get current value of SEM and store it in *SVAL. */
extern int sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval)
__THROW;
__END_DECLS
#endif<>/* semaphore.h */
/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2012 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Sam Lantinga
[email protected]
*/
#include "SDL_config.h"
/* An implementation of semaphores using mutexes and condition variables */
#include "SDL_timer.h"
#include "SDL_thread.h"
#include "SDL_systhread_c.h"
#if SDL_THREADS_DISABLED
SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
{
SDL_SetError("SDL not configured with thread support");
return (SDL_sem *)0;
}
void SDL_DestroySemaphore(SDL_sem *sem)
{
return;
}
int SDL_SemTryWait(SDL_sem *sem)
{
SDL_SetError("SDL not configured with thread support");
return -1;
}
int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
{
SDL_SetError("SDL not configured with thread support");
return -1;
}
int SDL_SemWait(SDL_sem *sem)
{
SDL_SetError("SDL not configured with thread support");
return -1;
}
Uint32 SDL_SemValue(SDL_sem *sem)
{
return 0;
}
int SDL_SemPost(SDL_sem *sem)
{
SDL_SetError("SDL not configured with thread support");
return -1;
}
#else
struct SDL_semaphore
{
Uint32 count;
Uint32 waiters_count;
SDL_mutex *count_lock;
SDL_cond *count_nonzero;
};
SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
{
SDL_sem *sem;
sem = (SDL_sem *)SDL_malloc(sizeof(*sem));
if ( ! sem ) {
SDL_OutOfMemory();
return NULL;
}
sem->count = initial_value;
sem->waiters_count = 0;
sem->count_lock = SDL_CreateMutex();
sem->count_nonzero = SDL_CreateCond();
if ( ! sem->count_lock || ! sem->count_nonzero ) {
SDL_DestroySemaphore(sem);
return NULL;
}
return sem;
}
/* WARNING:
You cannot call this function when another thread is using the semaphore.
*/
void SDL_DestroySemaphore(SDL_sem *sem)
{
if ( sem ) {
sem->count = 0xFFFFFFFF;
while ( sem->waiters_count > 0) {
SDL_CondSignal(sem->count_nonzero);
SDL_Delay(10);
}
SDL_DestroyCond(sem->count_nonzero);
if ( sem->count_lock ) {
SDL_mutexP(sem->count_lock);
SDL_mutexV(sem->count_lock);
SDL_DestroyMutex(sem->count_lock);
}
SDL_free(sem);
}
}
int SDL_SemTryWait(SDL_sem *sem)
{
int retval;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
retval = SDL_MUTEX_TIMEDOUT;
SDL_LockMutex(sem->count_lock);
if ( sem->count > 0 ) {
--sem->count;
retval = 0;
}
SDL_UnlockMutex(sem->count_lock);
return retval;
}
int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
{
int retval;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
/* A timeout of 0 is an easy case */
if ( timeout == 0 ) {
return SDL_SemTryWait(sem);
}
SDL_LockMutex(sem->count_lock);
++sem->waiters_count;
retval = 0;
while ( (sem->count == 0) && (retval != SDL_MUTEX_TIMEDOUT) ) {
retval = SDL_CondWaitTimeout(sem->count_nonzero,
sem->count_lock, timeout);
}
--sem->waiters_count;
if (retval == 0) {
--sem->count;
}
SDL_UnlockMutex(sem->count_lock);
return retval;
}
int SDL_SemWait(SDL_sem *sem)
{
return SDL_SemWaitTimeout(sem, SDL_MUTEX_MAXWAIT);
}
Uint32 SDL_SemValue(SDL_sem *sem)
{
Uint32 value;
value = 0;
if ( sem ) {
SDL_LockMutex(sem->count_lock);
value = sem->count;
SDL_UnlockMutex(sem->count_lock);
}
return value;
}
int SDL_SemPost(SDL_sem *sem)
{
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
SDL_LockMutex(sem->count_lock);
if ( sem->waiters_count > 0 ) {
SDL_CondSignal(sem->count_nonzero);
}
++sem->count;
SDL_UnlockMutex(sem->count_lock);
return 0;
}
#endif /* SDL_THREADS_DISABLED */
/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2012 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Sam Lantinga
[email protected]
*/
#include "SDL_config.h"
#include <pthread.h>
#include <semaphore.h>
#include <errno.h>
#include <sys/time.h>
#include "SDL_thread.h"
#include "SDL_timer.h"
/* Wrapper around POSIX 1003.1b semaphores */
#ifdef __MACOSX__
/* Mac OS X doesn't support sem_getvalue() as of version 10.4 */
#include "../generic/SDL_syssem.c"
#else
struct SDL_semaphore {
sem_t sem;
};
/* Create a semaphore, initialized with value */
SDL_sem *SDL_CreateSemaphore(Uint32 initial_value)
{
SDL_sem *sem = (SDL_sem *) SDL_malloc(sizeof(SDL_sem));
if ( sem ) {
if ( sem_init(&sem->sem, 0, initial_value) < 0 ) {
SDL_SetError("sem_init() failed");
SDL_free(sem);
sem = NULL;
}
} else {
SDL_OutOfMemory();
}
return sem;
}
void SDL_DestroySemaphore(SDL_sem *sem)
{
if ( sem ) {
sem_destroy(&sem->sem);
SDL_free(sem);
}
}
int SDL_SemTryWait(SDL_sem *sem)
{
int retval;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
retval = SDL_MUTEX_TIMEDOUT;
if ( sem_trywait(&sem->sem) == 0 ) {
retval = 0;
}
return retval;
}
int SDL_SemWait(SDL_sem *sem)
{
int retval;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
while ( ((retval = sem_wait(&sem->sem)) == -1) && (errno == EINTR) ) {}
if ( retval < 0 ) {
SDL_SetError("sem_wait() failed");
}
return retval;
}
int SDL_SemWaitTimeout(SDL_sem *sem, Uint32 timeout)
{
int retval;
struct timeval now;
struct timespec ts_timeout;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
/* Try the easy cases first */
if ( timeout == 0 ) {
return SDL_SemTryWait(sem);
}
if ( timeout == SDL_MUTEX_MAXWAIT ) {
return SDL_SemWait(sem);
}
/* Setup the timeout. sem_timedwait doesn't wait for
* a lapse of time, but until we reach a certain time.
* This time is now plus the timeout.
*/
gettimeofday(&now, NULL);
/* Add our timeout to current time */
now.tv_usec += (timeout % 1000) * 1000;
now.tv_sec += timeout / 1000;
/* Wrap the second if needed */
if ( now.tv_usec >= 1000000 ) {
now.tv_usec -= 1000000;
now.tv_sec ++;
}
/* Convert to timespec */
ts_timeout.tv_sec = now.tv_sec;
ts_timeout.tv_nsec = now.tv_usec * 1000;
/* Wait. */
do
retval = sem_timedwait(&sem->sem, &ts_timeout);
while (retval == -1 && errno == EINTR);
if (retval == -1)
SDL_SetError(strerror(errno));
return retval;
}
Uint32 SDL_SemValue(SDL_sem *sem)
{
int ret = 0;
if ( sem ) {
sem_getvalue(&sem->sem, &ret);
if ( ret < 0 ) {
ret = 0;
}
}
return (Uint32)ret;
}
int SDL_SemPost(SDL_sem *sem)
{
int retval;
if ( ! sem ) {
SDL_SetError("Passed a NULL semaphore");
return -1;
}
retval = sem_post(&sem->sem);
if ( retval < 0 ) {
SDL_SetError("sem_post() failed");
}
return retval;
}
#endif /* __MACOSX__ */
