godot/core/os/mutex.h

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/*  mutex.h                                                              */
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/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
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#ifndef MUTEX_H
#define MUTEX_H

#include "core/error_list.h"

/**
 * @class Mutex
 * @author Juan Linietsky
 * Portable Mutex (thread-safe locking) implementation.
 * Mutexes are always recursive ( they don't self-lock in a single thread ).
 * Mutexes can be used with a Lockp object like this, to avoid having to worry about unlocking:
 * Lockp( mutex );
 */

class Mutex {
protected:
	static Mutex *(*create_func)(bool);

public:
	virtual void lock() = 0; ///< Lock the mutex, block if locked by someone else
	virtual void unlock() = 0; ///< Unlock the mutex, let other threads continue
	virtual Error try_lock() = 0; ///< Attempt to lock the mutex, OK on success, ERROR means it can't lock.

	static Mutex *create(bool p_recursive = true); ///< Create a mutex

	virtual ~Mutex();
};

class MutexLock {

	Mutex *mutex;

public:
	MutexLock(Mutex *p_mutex) {
		mutex = p_mutex;
		if (mutex) mutex->lock();
	}
	~MutexLock() {
		if (mutex) mutex->unlock();
	}
};

#endif