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/*
* Copyright (c) 1999 Richard Seaman, Jr.
* All rights reserved.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Richard Seaman, Jr.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY RICHARD SEAMAN, Jr. 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 REGENTS 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 _THREAD_SAFE
#define _THREAD_SAFE
#endif
#include <dlfcn.h>
#include <stdlib.h>
#include "pthread.h"
/* Our internal pthreads definitions are here. Set as needed */
#if defined(COMPILING_UTHREADS)
#include "pthread_private.h"
#endif
#if defined(LINUXTHREADS)
#include <errno.h>
#include "internals.h"
#include "spinlock.h"
#else
/* Your internal definition here */
#endif
/* These are from lib/libc/include */
#if !defined(LINUXTHREADS)
#include "spinlock.h"
#endif
/* This is defined in lib/libc/stdlib/exit.c. It turns on thread safe
* behavior in libc if non-zero.
*/
extern int __isthreaded;
/* Optional. In case our code is dependant on the existence of
* the posix priority extentions kernel option.
*/
#if defined(LINUXTHREADS)
#include <sys/sysctl.h>
int _posix_priority_scheduling;
#endif
void *lock_create (void *context);
void rlock_acquire (void *lock);
void wlock_acquire (void *lock);
void lock_release (void *lock);
void lock_destroy (void *lock);
/* Use the constructor attribute so this gets run before main does */
static void _pthread_initialize(void) __attribute__((constructor));
static void _pthread_initialize(void)
{
#if defined(LINUXTHREADS)
int mib[2];
size_t len;
len = sizeof (_posix_priority_scheduling);
mib[0] = CTL_P1003_1B;
mib[1] = CTL_P1003_1B_PRIORITY_SCHEDULING;
if (-1 == sysctl (mib, 2, &_posix_priority_scheduling, &len, NULL, 0))
_posix_priority_scheduling = 0;
#endif
/* This turns on thread safe behaviour in libc when we link with it */
__isthreaded = 1;
}
void _spinlock (int * spinlock)
{
__pthread_acquire(spinlock);
}
void * lock_create (void *context)
{
pthread_rwlock_t *lock;
lock = malloc (sizeof (*lock));
if (lock == NULL)
return (NULL);
pthread_rwlock_init (lock, NULL);
return (lock);
}
void rlock_acquire (void *lock)
{
pthread_rwlock_rdlock ((pthread_rwlock_t *)lock);
}
void wlock_acquire (void *lock)
{
pthread_rwlock_wrlock ((pthread_rwlock_t *)lock);
}
void lock_release (void *lock)
{
pthread_rwlock_unlock ((pthread_rwlock_t *)lock);
}
void lock_destroy (void *lock)
{
if (pthread_rwlock_destroy ((pthread_rwlock_t *)lock) == 0)
free (lock);
}
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