// Truck Computer Dooom!
//
// Douglas Thrift
//
// $Id$

/* Menes - C++ High-Level Utility Library
 * Copyright (C) 2002-2004  Jay Freeman (saurik)
*/

/*
 *        Redistribution and use in source and binary
 * forms, with or without modification, are permitted
 * provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the
 *    above copyright notice, this list of conditions
 *    and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the
 *    above copyright notice, this list of conditions
 *    and the following disclaimer in the documentation
 *    and/or other materials provided with the
 *    distribution.
 * 3. The name of the author may not be used to endorse
 *    or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef _threads_hpp_
#define _threads_hpp_

#include "posix.hpp"

#include <pthread.h>
#include <semaphore.h>

namespace Pthreads
{

typedef Posix::Error Error;

inline void CheckError(int status)
{
	if (status != 0)
		throw Error(status);
}

class Thread
{
	::pthread_t thread;
	mutable bool joinable;
public:
	typedef void *(*Function)(void *);

	Thread(Function function, void *argument = NULL);
	~Thread();

	void Join() const;
};

class CriticalSection
{
protected:
	mutable pthread_mutex_t mutex;

public:
	CriticalSection()
	{
		CheckError(::pthread_mutex_init(&mutex, NULL));
	}

	~CriticalSection()
	{
		CheckError(::pthread_mutex_destroy(&mutex));
	}

	void Lock()
	{
		CheckError(::pthread_mutex_lock(&mutex));
	}

	void Unlock()
	{
		CheckError(::pthread_mutex_unlock(&mutex));
	}

	operator pthread_mutex_t *() const
	{
		return &mutex;
	}
};

class ThreadMutex
{
protected:
	CriticalSection *section;
	//ext::IndirectCount count;

public:
	ThreadMutex() : section(new CriticalSection)
	{
	}

	~ThreadMutex()
	{
		//if (count.Alone())
		delete section;
	}

	void Lock()
	{
		section->Lock();
	}

	void Unlock()
	{
		section->Unlock();
	}

	operator pthread_mutex_t *() const
	{
		return *section;
	}
};

class ThreadCondition
{
public:
	typedef ThreadMutex Mutex;

protected:
	mutable pthread_cond_t cond;
	Mutex &lock;
	//ext::IndirectCount count;

public:
	explicit ThreadCondition(Mutex &lock) : lock(lock)
	{
		CheckError(::pthread_cond_init(&cond, NULL));
	}

	~ThreadCondition()
	{
		//if (count.Alone())
		CheckError(::pthread_cond_destroy(&cond));
	}

	void Signal()
	{
		CheckError(::pthread_cond_signal(&cond));
	}

	void Broadcast()
	{
		CheckError(::pthread_cond_broadcast(&cond));
	}

	void Wait()
	{
		CheckError(::pthread_cond_wait(&cond, lock));
	}

	void Wait(const timespec &wait)
	{
		CheckError(::pthread_cond_timedwait(&cond, lock, &wait));
	}

	operator pthread_cond_t *() const
	{
		return &cond;
	}
};

class Semaphore
{
protected:
	sem_t handle;

	operator sem_t() const;

private:
	Semaphore(const Semaphore &rhs);

	Semaphore &operator =(const Semaphore &rhs);

public:
	explicit Semaphore(unsigned initial = 0)
	{
		Posix::CheckError(::sem_init(&handle, 0, initial));
	}

	~Semaphore()
	{
		Posix::CheckError(::sem_destroy(&handle));
	}

	void Acquire()
	{
		Posix::CheckError(::sem_wait(&handle));
	}

	void Release(unsigned number = 1)
	{
		Posix::CheckError(::sem_post(&handle));
	}
};

}

#endif//_threads_hpp_