1/**************************************************************************/
2/* rw_lock.h */
3/**************************************************************************/
4/* This file is part of: */
5/* GODOT ENGINE */
6/* https://godotengine.org */
7/**************************************************************************/
8/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
9/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
10/* */
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13/* "Software"), to deal in the Software without restriction, including */
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17/* the following conditions: */
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20/* included in all copies or substantial portions of the Software. */
21/* */
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29/**************************************************************************/
30
31#ifndef RW_LOCK_H
32#define RW_LOCK_H
33
34#include "core/typedefs.h"
35
36#include <shared_mutex>
37
38class RWLock {
39 mutable std::shared_timed_mutex mutex;
40
41public:
42 // Lock the RWLock, block if locked by someone else.
43 _ALWAYS_INLINE_ void read_lock() const {
44 mutex.lock_shared();
45 }
46
47 // Unlock the RWLock, let other threads continue.
48 _ALWAYS_INLINE_ void read_unlock() const {
49 mutex.unlock_shared();
50 }
51
52 // Attempt to lock the RWLock for reading. True on success, false means it can't lock.
53 _ALWAYS_INLINE_ bool read_try_lock() const {
54 return mutex.try_lock_shared();
55 }
56
57 // Lock the RWLock, block if locked by someone else.
58 _ALWAYS_INLINE_ void write_lock() {
59 mutex.lock();
60 }
61
62 // Unlock the RWLock, let other threads continue.
63 _ALWAYS_INLINE_ void write_unlock() {
64 mutex.unlock();
65 }
66
67 // Attempt to lock the RWLock for writing. True on success, false means it can't lock.
68 _ALWAYS_INLINE_ bool write_try_lock() {
69 return mutex.try_lock();
70 }
71};
72
73class RWLockRead {
74 const RWLock &lock;
75
76public:
77 _ALWAYS_INLINE_ RWLockRead(const RWLock &p_lock) :
78 lock(p_lock) {
79 lock.read_lock();
80 }
81 _ALWAYS_INLINE_ ~RWLockRead() {
82 lock.read_unlock();
83 }
84};
85
86class RWLockWrite {
87 RWLock &lock;
88
89public:
90 _ALWAYS_INLINE_ RWLockWrite(RWLock &p_lock) :
91 lock(p_lock) {
92 lock.write_lock();
93 }
94 _ALWAYS_INLINE_ ~RWLockWrite() {
95 lock.write_unlock();
96 }
97};
98
99#endif // RW_LOCK_H
100