RetroShare/libretroshare/src/util/rsthreads.h

#ifndef RSIFACE_THREADS_H
#define RSIFACE_THREADS_H

/*
 * "$Id: rsthreads.h,v 1.1 2007-02-19 20:08:30 rmf24 Exp $"
 *
 * RetroShare C++ Interface.
 *
 * Copyright 2004-2006 by Robert Fernie.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License Version 2 as published by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA.
 *
 * Please report all bugs and problems to "retroshare@lunamutt.com".
 *
 */


#ifdef WINDOWS_SYS
#include "util/rswin.h"
#endif

#include <pthread.h>
#include <inttypes.h>

/* RsIface Thread Wrappers */

#undef RSTHREAD_SELF_LOCKING_GUARD

class RsMutex
{
	public:

	RsMutex() 
        {
		pthread_mutex_init(&realMutex, NULL); 
#ifdef RSTHREAD_SELF_LOCKING_GUARD
		//_thread_id = {NULL, 0} ; // need c++
		_thread_id.p = NULL;
		_thread_id.x = 0;
#endif
	}
	~RsMutex() 
	{ 
		pthread_mutex_destroy(&realMutex); 
	}

	void	lock() 
	{ 
#ifdef RSTHREAD_SELF_LOCKING_GUARD
		if(!trylock())
			if(!pthread_equal(_thread_id,pthread_self()))
#endif
				pthread_mutex_lock(&realMutex); 

#ifdef RSTHREAD_SELF_LOCKING_GUARD
		_thread_id = pthread_self() ;
		++_cnt ;
#endif
	}
	void	unlock() 
	{ 
#ifdef RSTHREAD_SELF_LOCKING_GUARD
		if(--_cnt == 0)
		{
			//_thread_id = {NULL, 0} ; // need c++
			_thread_id.p = NULL;
			_thread_id.x = 0;
#endif
			pthread_mutex_unlock(&realMutex);
#ifdef RSTHREAD_SELF_LOCKING_GUARD
		}
#endif
	}
	bool	trylock() { return (0 == pthread_mutex_trylock(&realMutex)); }

	private:
		pthread_mutex_t  realMutex;
#ifdef RSTHREAD_SELF_LOCKING_GUARD
		pthread_t _thread_id ;
		uint32_t _cnt ;
#endif
};

class RsStackMutex
{
	public:

	RsStackMutex(RsMutex &mtx): mMtx(mtx) { mMtx.lock(); }
        ~RsStackMutex() { mMtx.unlock(); }

	private:
	RsMutex &mMtx;
};

class RsReadWriteMutex: public RsMutex
{
        public:
        RsReadWriteMutex();

        void readLock();
        void readUnlock();
        void writeLock();
        void writeUnlock();

        void rwlock(uint32_t type);
        void rwunlock(uint32_t type);

        const static uint32_t READ_LOCK = 0x0001;
        const static uint32_t WRITE_LOCK = 0x0002;


        private:
        int readLocks;
        RsMutex internalCounterMtx;
};

class RsStackReadWriteMutex
{
        public:

        RsStackReadWriteMutex(RsReadWriteMutex &mtx): mMtx(mtx) {  mMtx.writeLock(); writeLock = true;}
        RsStackReadWriteMutex(RsReadWriteMutex &mtx, uint32_t type): mMtx(mtx) {  if (type == RsReadWriteMutex::READ_LOCK) {mMtx.readLock(); writeLock = false;} else {mMtx.writeLock(); writeLock = true;} }
        ~RsStackReadWriteMutex() { if(writeLock) {mMtx.writeUnlock();} else {mMtx.readUnlock();} }

        private:
        RsReadWriteMutex &mMtx;
        bool writeLock;
};

class RsThread;

/* to create a thread! */
pthread_t  createThread(RsThread &thread);

class RsThread
{
	public:
	RsThread();
virtual ~RsThread() {}

virtual void start() { createThread(*this); }
virtual void run() = 0; /* called once the thread is started */
virtual	void join(); /* waits for the the mTid thread to stop */
virtual	void stop(); /* calls pthread_exit() */

	pthread_t mTid;
        RsMutex   mMutex;
protected:
	bool m_bRun;
};


class RsQueueThread: public RsThread
{
	public:

	RsQueueThread(uint32_t min, uint32_t max, double relaxFactor );
virtual ~RsQueueThread() { return; }

virtual void run();

	protected:

virtual bool workQueued() = 0;
virtual bool doWork() = 0;

	private:
	uint32_t mMinSleep; /* ms */
	uint32_t mMaxSleep; /* ms */
	uint32_t mLastSleep; /* ms */
	time_t   mLastWork;  /* secs */
	float    mRelaxFactor; 
};


#endif