godot/core/os/semaphore.h

/*************************************************************************/
/*  semaphore.h                                                          */
/*************************************************************************/
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/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2018 Godot Engine contributors (cf. AUTHORS.md)    */
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#ifndef SEMAPHORE_H
#define SEMAPHORE_H

#include "error_list.h"

/**
	@author Juan Linietsky <reduzio@gmail.com>
*/
class Semaphore {
protected:
	static Semaphore *(*create_func)();

public:
	virtual Error wait() = 0; ///< wait until semaphore has positive value, then decrement and pass
	virtual Error post() = 0; ///< unlock the semaphore, incrementing the    value
	virtual int get() const = 0; ///< get semaphore value

	static Semaphore *create(); ///< Create a mutex

	virtual ~Semaphore();
};

#endif