godot/core/os/rw_lock.h

/*************************************************************************/
/*  rw_lock.h                                                            */
/*************************************************************************/
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/*                           GODOT ENGINE                                */
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/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md)    */
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#ifndef RWLOCK_H
#define RWLOCK_H

#include "error_list.h"

class RWLock {
protected:
	static RWLock *(*create_func)();

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

	virtual void write_lock() = 0; ///< Lock the rwlock, block if locked by someone else
	virtual void write_unlock() = 0; ///< Unlock the rwlock, let other thwrites continue
	virtual Error write_try_lock() = 0; ///< Attempt to lock the rwlock, OK on success, ERROR means it can't lock.

	static RWLock *create(); ///< Create a rwlock

	virtual ~RWLock();
};

class RWLockRead {

	RWLock *lock;

public:
	RWLockRead(RWLock *p_lock) {
		lock = p_lock;
		if (lock) lock->read_lock();
	}
	~RWLockRead() {
		if (lock) lock->read_unlock();
	}
};

class RWLockWrite {

	RWLock *lock;

public:
	RWLockWrite(RWLock *p_lock) {
		lock = p_lock;
		if (lock) lock->write_lock();
	}
	~RWLockWrite() {
		if (lock) lock->write_unlock();
	}
};

#endif // RWLOCK_H