initial commit, 4.5 stable

core/os/mutex.h

@@ -0,0 +1,128 @@
+/**************************************************************************/
+/*  mutex.h                                                               */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* 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.                 */
+/**************************************************************************/
+
+#pragma once
+
+#include "core/typedefs.h"
+
+#ifdef MINGW_ENABLED
+#define MINGW_STDTHREAD_REDUNDANCY_WARNING
+#include "thirdparty/mingw-std-threads/mingw.mutex.h"
+#define THREADING_NAMESPACE mingw_stdthread
+#else
+#include <mutex>
+#define THREADING_NAMESPACE std
+#endif
+
+#ifdef THREADS_ENABLED
+
+template <typename MutexT>
+class MutexLock;
+
+template <typename StdMutexT>
+class MutexImpl {
+	friend class MutexLock<MutexImpl<StdMutexT>>;
+
+	using StdMutexType = StdMutexT;
+
+	mutable StdMutexT mutex;
+
+public:
+	_ALWAYS_INLINE_ void lock() const {
+		mutex.lock();
+	}
+
+	_ALWAYS_INLINE_ void unlock() const {
+		mutex.unlock();
+	}
+
+	_ALWAYS_INLINE_ bool try_lock() const {
+		return mutex.try_lock();
+	}
+};
+
+template <typename MutexT>
+class MutexLock {
+	mutable THREADING_NAMESPACE::unique_lock<typename MutexT::StdMutexType> lock;
+
+public:
+	explicit MutexLock(const MutexT &p_mutex) :
+			lock(p_mutex.mutex) {}
+
+	// Clarification: all the funny syntax is needed so this function exists only for binary mutexes.
+	template <typename T = MutexT>
+	_ALWAYS_INLINE_ THREADING_NAMESPACE::unique_lock<THREADING_NAMESPACE::mutex> &_get_lock(
+			typename std::enable_if<std::is_same<T, THREADING_NAMESPACE::mutex>::value> * = nullptr) const {
+		return lock;
+	}
+
+	_ALWAYS_INLINE_ void temp_relock() const {
+		lock.lock();
+	}
+
+	_ALWAYS_INLINE_ void temp_unlock() const {
+		lock.unlock();
+	}
+
+	// TODO: Implement a `try_temp_relock` if needed (will also need a dummy method below).
+};
+
+using Mutex = MutexImpl<THREADING_NAMESPACE::recursive_mutex>; // Recursive, for general use
+using BinaryMutex = MutexImpl<THREADING_NAMESPACE::mutex>; // Non-recursive, handle with care
+
+extern template class MutexImpl<THREADING_NAMESPACE::recursive_mutex>;
+extern template class MutexImpl<THREADING_NAMESPACE::mutex>;
+extern template class MutexLock<MutexImpl<THREADING_NAMESPACE::recursive_mutex>>;
+extern template class MutexLock<MutexImpl<THREADING_NAMESPACE::mutex>>;
+
+#else // No threads.
+
+class MutexImpl {
+	mutable THREADING_NAMESPACE::mutex mutex;
+
+public:
+	void lock() const {}
+	void unlock() const {}
+	bool try_lock() const { return true; }
+};
+
+template <typename MutexT>
+class MutexLock {
+public:
+	MutexLock(const MutexT &p_mutex) {}
+
+	void temp_relock() const {}
+	void temp_unlock() const {}
+};
+
+using Mutex = MutexImpl;
+using BinaryMutex = MutexImpl;
+
+#endif // THREADS_ENABLED