/*
 * Copyright (c)2019 ZeroTier, Inc.
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file in the project's root directory.
 *
 * Change Date: 2025-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2.0 of the Apache License.
 */
/****/

#ifndef ZT_MUTEX_HPP
#define ZT_MUTEX_HPP

#include "Constants.hpp"

#ifdef __UNIX_LIKE__

#include <stdint.h>
#include <stdlib.h>
#include <pthread.h>

namespace ZeroTier {

// libpthread based mutex lock
class Mutex
{
public:
	Mutex()
	{
		pthread_mutex_init(&_mh,(const pthread_mutexattr_t *)0);
	}

	~Mutex()
	{
		pthread_mutex_destroy(&_mh);
	}

	inline void lock() const
	{
		pthread_mutex_lock(&((const_cast <Mutex *> (this))->_mh));
	}

	inline void unlock() const
	{
		pthread_mutex_unlock(&((const_cast <Mutex *> (this))->_mh));
	}

	class Lock
	{
	public:
		Lock(Mutex &m) :
			_m(&m)
		{
			m.lock();
		}

		Lock(const Mutex &m) :
			_m(const_cast<Mutex *>(&m))
		{
			_m->lock();
		}

		~Lock()
		{
			_m->unlock();
		}

	private:
		Mutex *const _m;
	};

private:
	Mutex(const Mutex &) {}
	const Mutex &operator=(const Mutex &) { return *this; }

	pthread_mutex_t _mh;
};

} // namespace ZeroTier

#endif

#ifdef __WINDOWS__

#include <stdlib.h>
#include <windows.h>

namespace ZeroTier {

// Windows critical section based lock
class Mutex
{
public:
	Mutex()
	{
		InitializeCriticalSection(&_cs);
	}

	~Mutex()
	{
		DeleteCriticalSection(&_cs);
	}

	inline void lock()
	{
		EnterCriticalSection(&_cs);
	}

	inline void unlock()
	{
		LeaveCriticalSection(&_cs);
	}

	inline void lock() const
	{
		(const_cast <Mutex *> (this))->lock();
	}

	inline void unlock() const
	{
		(const_cast <Mutex *> (this))->unlock();
	}

	class Lock
	{
	public:
		Lock(Mutex &m) :
			_m(&m)
		{
			m.lock();
		}

		Lock(const Mutex &m) :
			_m(const_cast<Mutex *>(&m))
		{
			_m->lock();
		}

		~Lock()
		{
			_m->unlock();
		}

	private:
		Mutex *const _m;
	};

private:
	Mutex(const Mutex &) {}
	const Mutex &operator=(const Mutex &) { return *this; }

	CRITICAL_SECTION _cs;
};

} // namespace ZeroTier

#endif // _WIN32

#endif
