winamp/Src/external_dependencies/openmpt-trunk/soundlib/AudioCriticalSection.h

/*
 * AudioCriticalSection.h
 * ---------
 * Purpose: Implementation of OpenMPT's critical section for access to CSoundFile.
 * Notes  : (currently none)
 * Authors: OpenMPT Devs
 * The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
 */

#pragma once

#include "openmpt/all/BuildSettings.hpp"

#if defined(MODPLUG_TRACKER)
#include "../misc/mptMutex.h"
#endif

OPENMPT_NAMESPACE_BEGIN

#if defined(MODPLUG_TRACKER)

namespace mpt {
class recursive_mutex_with_lock_count;
} // namespace mpt

namespace Tracker { // implemented in mptrack/Mptrack.cpp
mpt::recursive_mutex_with_lock_count & GetGlobalMutexRef();
} // namespace Tracker

// Critical section handling done in (safe) RAII style.
// Create a CriticalSection object whenever you need exclusive access to CSoundFile.
// One object = one lock / critical section.
// The critical section is automatically left when the object is destroyed, but
// Enter() and Leave() can also be called manually if needed.
class CriticalSection
{

private:
	
	mpt::recursive_mutex_with_lock_count & m_refGlobalMutex;

protected:

	bool inSection;

public:

	enum class InitialState
	{
		Locked = 0,
		Unlocked = 1,
	};

public:

#if MPT_COMPILER_MSVC
	_Acquires_lock_(m_refGlobalMutex.mutex)
#endif // MPT_COMPILER_MSVC
	CriticalSection();

	CriticalSection(CriticalSection &&other) noexcept;

	explicit CriticalSection(InitialState state);

#if MPT_COMPILER_MSVC
	_Acquires_lock_(m_refGlobalMutex.mutex)
#endif // MPT_COMPILER_MSVC
	void Enter();

#if MPT_COMPILER_MSVC
	_Requires_lock_held_(m_refGlobalMutex.mutex) _Releases_lock_(m_refGlobalMutex.mutex)
#endif // MPT_COMPILER_MSVC
	void Leave();

	~CriticalSection();

};

#else // !MODPLUG_TRACKER

class CriticalSection
{
public:
	enum class InitialState
	{
		Locked = 0,
		Unlocked = 1,
	};
public:
	CriticalSection() {}
	CriticalSection(CriticalSection &&) noexcept {}
	explicit CriticalSection(InitialState) {}
	void Enter() {}
	void Leave() {}
	~CriticalSection() {}
};

#endif // MODPLUG_TRACKER

OPENMPT_NAMESPACE_END