workerthread.cpp

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/*
 *
 * workerthread.cpp
 *
   Copyright (C) 2006 Michael H. Overlin

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   
   Contact at [e-mail]
 *
 */

#include "workerthread.h"

#include "utils.h"

#include <process.h>

WorkerThread::WorkerThread(void) {
	m_hThread = NULL;
}

WorkerThread::~WorkerThread() {
	ASSERT(m_hThread == NULL);
}

BOOL WorkerThread::StartNewDoWorkThread(void) {
	m_hThread = (HANDLE) ::_beginthread( WorkerThread::TheirThreadProc, 0,  this);
	BOOL bRetValue = (m_hThread != NULL);
	return bRetValue;
}

BOOL WorkerThread::PeekMessagesUntilTerminate(DWORD dwWaitTimeSlice, DWORD dwTotalWaitMS) {
	BOOL bTerminated = FALSE;
	DWORD dwStartMS = ::GetTickCount();
	while( 
		!bTerminated && 
		(dwTotalWaitMS == INFINITE || GetTickCount() - dwStartMS < dwTotalWaitMS)
	) {
		bTerminated = this->WaitOnTerminate(dwWaitTimeSlice);
	}
	return bTerminated;
}

BOOL WorkerThread::WaitOnTerminate(DWORD dwWaitTimeSliceMS) {
	BOOL bRetValue = TRUE;
	if (m_hThread != NULL) {
		DWORD dw = ::WaitForSingleObject(m_hThread, dwWaitTimeSliceMS);
		bRetValue = (dw != WAIT_TIMEOUT);
		if (bRetValue) {
			m_hThread = NULL;
		}
	}
	return bRetValue;
}


void __cdecl WorkerThread::TheirThreadProc(void *pv) {
	WorkerThread *pwt = (WorkerThread *) pv;
	pwt->DoWork();
	// 7/9 REMOVE THIS, SEEING SOME UNEXPLAINED THREAD LOCKING
	// THIS IS NOT REQUIRED FOR THREADS STARTED WITH "beginthread"
	//_endthread();
}

//class WorkerThread {
//public:
//	WorkerThread(void);
//	virtual ~WorkerThread();
//
//	virtual BOOL PeekMessagesUntilTerminate(DWORD dwWaitTimeSlice, DWORD dwTotalWaitMS);
//	virtual BOOL WaitOnTerminate(DWORD dwWaitMS);
//	virtual void DoWork(void);
//
//private:
//	HANDLE m_hThread;
//
//	static __cdecl void TheirThreadProc(void *pv);
//};