1 /*************************************************************************/
2 /*  semaphore.h                                                          */
3 /*************************************************************************/
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5 /*                           GODOT ENGINE                                */
6 /*                      https://godotengine.org                          */
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8 /* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
9 /* Copyright (c) 2014-2019 Godot Engine contributors (cf. AUTHORS.md)    */
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29 /*************************************************************************/
30 #ifndef SEMAPHORE_H
31 #define SEMAPHORE_H
32 
33 #include "error_list.h"
34 
35 /**
36 	@author Juan Linietsky <reduzio@gmail.com>
37 */
38 class Semaphore {
39 protected:
40 	static Semaphore *(*create_func)();
41 
42 public:
43 	virtual Error wait() = 0; ///< wait until semaphore has positive value, then decrement and pass
44 	virtual Error post() = 0; ///< unlock the semaphore, incrementing the    value
45 	virtual int get() const = 0; ///< get semaphore value
46 
47 	static Semaphore *create(); ///< Create a mutex
48 
49 	virtual ~Semaphore();
50 };
51 
52 #endif
53