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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2023 Red Hat
*/
#include <errno.h>
#include "logger.h"
#include "permassert.h"
#include "thread-utils.h"
#include "time-utils.h"
/**********************************************************************/
int uds_initialize_semaphore(struct semaphore *semaphore, unsigned int value)
{
int result;
result = sem_init(&semaphore->semaphore, false, value);
VDO_ASSERT_LOG_ONLY((result == 0), "sem_init error");
return result;
}
/**********************************************************************/
int uds_destroy_semaphore(struct semaphore *semaphore)
{
int result;
result = sem_destroy(&semaphore->semaphore);
VDO_ASSERT_LOG_ONLY((result == 0), "sem_destroy error");
return result;
}
/**********************************************************************/
void uds_acquire_semaphore(struct semaphore *semaphore)
{
int result;
do {
result = sem_wait(&semaphore->semaphore);
} while ((result == -1) && (errno == EINTR));
#ifndef NDEBUG
VDO_ASSERT_LOG_ONLY((result == 0), "sem_wait error %d", errno);
#endif
}
/**********************************************************************/
bool uds_attempt_semaphore(struct semaphore *semaphore, ktime_t timeout)
{
if (timeout > 0) {
struct timespec ts = future_time(timeout);
do {
if (sem_timedwait(&semaphore->semaphore, &ts) == 0)
return true;
} while (errno == EINTR);
#ifndef NDEBUG
VDO_ASSERT_LOG_ONLY((errno == ETIMEDOUT),
"sem_timedwait error %d",
errno);
#endif
} else {
do {
if (sem_trywait(&semaphore->semaphore) == 0)
return true;
} while (errno == EINTR);
#ifndef NDEBUG
VDO_ASSERT_LOG_ONLY((errno == EAGAIN),
"sem_trywait error %d",
errno);
#endif
}
return false;
}
/**********************************************************************/
void uds_release_semaphore(struct semaphore *semaphore)
{
int result __attribute__((unused));
result = sem_post(&semaphore->semaphore);
#ifndef NDEBUG
VDO_ASSERT_LOG_ONLY((result == 0), "sem_post error %d", errno);
#endif
}
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