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//
// semaphore.c
//
// POSIX semaphore library
//
// Copyright (C) 2002 Michael Ringgaard. 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. Neither the name of the project nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
//
#include <os.h>
#include <semaphore.h>
int sem_init(sem_t *sem, int pshared, unsigned int value) {
if (pshared) {
errno = EPERM;
return -1;
}
*sem = mksem(value);
if (*sem < 0) {
errno = ENOSPC;
return -1;
}
return 0;
}
int sem_destroy(sem_t *sem) {
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (close(*sem) < 0) {
errno = EINVAL;
return -1;
}
*sem = -1;
return 0;
}
int sem_trywait(sem_t *sem) {
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (waitone(*sem, 0) < 0) {
errno = EAGAIN;
return -1;
}
return 0;
}
int sem_wait(sem_t * sem) {
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (waitone(*sem, INFINITE) < 0) return -1;
return 0;
}
int sem_timedwait(sem_t *sem, const struct timespec *abstime) {
struct timeval curtime;
long timeout;
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (gettimeofday(&curtime, NULL) < 0) return -1;
timeout = ((long) (abstime->tv_sec - curtime.tv_sec) * 1000L +
(long)((abstime->tv_nsec / 1000) - curtime.tv_usec) / 1000L);
if (timeout < 0) timeout = 0L;
if (waitone(*sem, timeout) < 0) return -1;
return 0;
}
int sem_post(sem_t *sem) {
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (semrel(*sem, 1) < 0) {
errno = EINVAL;
return -1;
}
return 0;
}
int sem_post_multiple(sem_t *sem, int count) {
if (!sem || *sem == -1) {
errno = EINVAL;
return -1;
}
if (semrel(*sem, count) < 0) {
errno = EINVAL;
return -1;
}
return 0;
}
int sem_open(const char *name, int oflag, int mode, unsigned int value) {
errno = ENOSYS;
return -1;
}
int sem_close(sem_t *sem) {
errno = ENOSYS;
return -1;
}
int sem_unlink(const char *name) {
errno = ENOSYS;
return -1;
}
int sem_getvalue(sem_t *sem, int *sval) {
errno = ENOSYS;
return -1;
}