/*
* Copyright (c) 2008-2024 Jonathan Schleifer <js@nil.im>
*
* All rights reserved.
*
* This file is part of ObjFW. It may be distributed under the terms of the
* Q Public License 1.0, which can be found in the file LICENSE.QPL included in
* the packaging of this file.
*
* Alternatively, it may be distributed under the terms of the GNU General
* Public License, either version 2 or 3, which can be found in the file
* LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
* file.
*/
#include "objfw-defs.h"
#import "macros.h"
#if defined(OF_HAVE_PTHREADS)
# include <pthread.h>
typedef pthread_once_t OFOnceControl;
# define OFOnceControlInitValue PTHREAD_ONCE_INIT
#elif defined(OF_HAVE_ATOMIC_OPS)
typedef volatile int OFOnceControl;
# define OFOnceControlInitValue 0
#elif defined(OF_AMIGAOS) || !defined(OF_HAVE_THREADS)
typedef int OFOnceControl;
# define OFOnceControlInitValue 0
#endif
OF_ASSUME_NONNULL_BEGIN
/** @file */
typedef void (*OFOnceFunction)(void);
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Executes the specified function exactly once in the application's
* lifetime, even in a multi-threaded environment.
*
* @param control An OFOnceControl. This should be a static variable
* preinitialized to `OFOnceControlInitValue`.
* @param function The function to execute once
*/
extern void OFOnce(OFOnceControl *control, OFOnceFunction function);
#ifdef __cplusplus
}
#endif
OF_ASSUME_NONNULL_END