4ddcdc031b
- Based on C++11's `mutex` - No more need to allocate-deallocate or check for null - No pointer anymore, just a member variable - Platform-specific implementations no longer needed - Simpler for `NO_THREADS` - `BinaryMutex` added for special cases as the non-recursive version - `MutexLock` now takes a reference. At this point the cases of null `Mutex`es are rare. If you ever need that, just don't use `MutexLock`. - `ScopedMutexLock` is dropped and replaced by `MutexLock`, because they were pretty much the same.
121 lines
4 KiB
C++
121 lines
4 KiB
C++
/*************************************************************************/
|
|
/* mutex.h */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* https://godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
|
|
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
|
|
/* */
|
|
/* Permission is hereby granted, free of charge, to any person obtaining */
|
|
/* a copy of this software and associated documentation files (the */
|
|
/* "Software"), to deal in the Software without restriction, including */
|
|
/* without limitation the rights to use, copy, modify, merge, publish, */
|
|
/* distribute, sublicense, and/or sell copies of the Software, and to */
|
|
/* permit persons to whom the Software is furnished to do so, subject to */
|
|
/* the following conditions: */
|
|
/* */
|
|
/* The above copyright notice and this permission notice shall be */
|
|
/* included in all copies or substantial portions of the Software. */
|
|
/* */
|
|
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
|
|
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
|
|
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
|
|
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
|
|
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
|
|
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
|
|
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
/*************************************************************************/
|
|
|
|
#ifndef MUTEX_H
|
|
#define MUTEX_H
|
|
|
|
#include "core/error_list.h"
|
|
#include "core/typedefs.h"
|
|
|
|
#if !defined(NO_THREADS)
|
|
|
|
#include <mutex>
|
|
|
|
template <class StdMutexT>
|
|
class MutexImpl {
|
|
mutable StdMutexT mutex;
|
|
friend class MutexLock;
|
|
|
|
public:
|
|
_ALWAYS_INLINE_ void lock() const {
|
|
mutex.lock();
|
|
}
|
|
|
|
_ALWAYS_INLINE_ void unlock() const {
|
|
mutex.unlock();
|
|
}
|
|
|
|
_ALWAYS_INLINE_ Error try_lock() const {
|
|
return mutex.try_lock() ? OK : ERR_BUSY;
|
|
}
|
|
};
|
|
|
|
// This is written this way instead of being a template to overcome a limitation of C++ pre-17
|
|
// that would require MutexLock to be used like this: MutexLock<Mutex> lock;
|
|
class MutexLock {
|
|
union {
|
|
std::recursive_mutex *recursive_mutex;
|
|
std::mutex *mutex;
|
|
};
|
|
bool recursive;
|
|
|
|
public:
|
|
_ALWAYS_INLINE_ explicit MutexLock(const MutexImpl<std::recursive_mutex> &p_mutex) :
|
|
recursive_mutex(&p_mutex.mutex),
|
|
recursive(true) {
|
|
recursive_mutex->lock();
|
|
}
|
|
_ALWAYS_INLINE_ explicit MutexLock(const MutexImpl<std::mutex> &p_mutex) :
|
|
mutex(&p_mutex.mutex),
|
|
recursive(false) {
|
|
mutex->lock();
|
|
}
|
|
|
|
_ALWAYS_INLINE_ ~MutexLock() {
|
|
if (recursive) {
|
|
recursive_mutex->unlock();
|
|
} else {
|
|
mutex->unlock();
|
|
}
|
|
}
|
|
};
|
|
|
|
using Mutex = MutexImpl<std::recursive_mutex>; // Recursive, for general use
|
|
using BinaryMutex = MutexImpl<std::mutex>; // Non-recursive, handle with care
|
|
|
|
extern template class MutexImpl<std::recursive_mutex>;
|
|
extern template class MutexImpl<std::mutex>;
|
|
|
|
#else
|
|
|
|
class FakeMutex {
|
|
FakeMutex() {}
|
|
};
|
|
|
|
template <class MutexT>
|
|
class MutexImpl {
|
|
public:
|
|
_ALWAYS_INLINE_ void lock() const {}
|
|
_ALWAYS_INLINE_ void unlock() const {}
|
|
_ALWAYS_INLINE_ Error try_lock() const { return OK; }
|
|
};
|
|
|
|
class MutexLock {
|
|
public:
|
|
explicit MutexLock(const MutexImpl<FakeMutex> &p_mutex) {}
|
|
};
|
|
|
|
using Mutex = MutexImpl<FakeMutex>;
|
|
using BinaryMutex = MutexImpl<FakeMutex>; // Non-recursive, handle with care
|
|
|
|
#endif // !NO_THREADS
|
|
|
|
#endif // MUTEX_H
|