godot/drivers/unix/semaphore_posix.cpp

/*************************************************************************/
/*  semaphore_posix.cpp                                                  */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
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/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
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#include "semaphore_posix.h"

#if defined(UNIX_ENABLED) || defined(PTHREAD_ENABLED)

#include "core/os/memory.h"
#include <errno.h>
#include <stdio.h>

Error SemaphorePosix::wait() {

	while (sem_wait(&sem)) {
		if (errno == EINTR) {
			errno = 0;
			continue;
		} else {
			perror("sem waiting");
			return ERR_BUSY;
		}
	}
	return OK;
}

Error SemaphorePosix::post() {

	return (sem_post(&sem) == 0) ? OK : ERR_BUSY;
}
int SemaphorePosix::get() const {

	int val;
	sem_getvalue(&sem, &val);

	return val;
}

Semaphore *SemaphorePosix::create_semaphore_posix() {

	return memnew(SemaphorePosix);
}

void SemaphorePosix::make_default() {

	create_func = create_semaphore_posix;
}

SemaphorePosix::SemaphorePosix() {

	int r = sem_init(&sem, 0, 0);
	if (r != 0)
		perror("sem creating");
}

SemaphorePosix::~SemaphorePosix() {

	sem_destroy(&sem);
}

#endif