eqemu-server/common/condition.cpp

/*	EQEmu: EQEmulator

	Copyright (C) 2001-2026 EQEmu Development Team

	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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include "condition.h"

#ifdef _WINDOWS

	Condition::Condition()
	{
		m_events[SignalEvent] = CreateEvent (nullptr, // security
										FALSE, // is auto-reset event?
										FALSE, // is signaled initially?
										nullptr); // name
		m_events[BroadcastEvent] = CreateEvent (nullptr, // security
										TRUE, // is auto-reset event?
										FALSE, // is signaled initially?
										nullptr); // name
		m_waiters = 0;
		InitializeCriticalSection(&CSMutex);
	}

	Condition::~Condition()
	{
		DeleteCriticalSection(&CSMutex);
		CloseHandle(m_events[SignalEvent]);
		CloseHandle(m_events[BroadcastEvent]);
	}

	void Condition::Signal()
	{
		EnterCriticalSection(&CSMutex);
		if(m_waiters > 0)
			SetEvent(m_events[SignalEvent]);
		LeaveCriticalSection(&CSMutex);
	}

	void Condition::SignalAll()
	{
		EnterCriticalSection(&CSMutex);
		if(m_waiters > 0)
			SetEvent(m_events[BroadcastEvent]);
		LeaveCriticalSection(&CSMutex);
	}

	void Condition::Wait()
	{
		EnterCriticalSection(&CSMutex);

		m_waiters++;


		LeaveCriticalSection(&CSMutex);
		int result = WaitForMultipleObjects (_eventCount, m_events, FALSE, INFINITE);
		EnterCriticalSection(&CSMutex);

		m_waiters--;

		//see if we are the last person waiting on the condition, and there was a broadcast
		//if so, we need to reset the broadcast event.
		if(m_waiters == 0 && result == (WAIT_OBJECT_0+BroadcastEvent))
			ResetEvent(m_events[BroadcastEvent]);

		LeaveCriticalSection(&CSMutex);
	}

#else
	#include <pthread.h>
	#include <sys/time.h>
	#include <errno.h>
	
	Condition::Condition()
	{
		pthread_cond_init(&cond,nullptr);
		pthread_mutex_init(&mutex,nullptr);
	}

	void Condition::Signal()
	{
		pthread_mutex_lock(&mutex);
		pthread_cond_signal(&cond);
		pthread_mutex_unlock(&mutex);
	}

	void Condition::SignalAll()
	{
		pthread_mutex_lock(&mutex);
		pthread_cond_broadcast(&cond);
		pthread_mutex_unlock(&mutex);
	}

	void Condition::Wait()
	{
		pthread_mutex_lock(&mutex);
		pthread_cond_wait(&cond,&mutex);
		pthread_mutex_unlock(&mutex);
	}

	/*
	I commented this specifically because I think it might be very
	difficult to write a windows counterpart to it, so I would like
	to discourage its use until we can confirm that it can be reasonably
	implemented on windows.

	bool Condition::TimedWait(unsigned long usec)
	{
	struct timeval now;
	struct timespec timeout;
	int retcode=0;
		pthread_mutex_lock(&mutex);
		gettimeofday(&now,nullptr);
		now.tv_usec+=usec;
		timeout.tv_sec = now.tv_sec + (now.tv_usec/1000000);
		timeout.tv_nsec = (now.tv_usec%1000000) *1000;
		//cout << "now=" << now.tv_sec << "."<<now.tv_usec << endl;
		//cout << "timeout=" << timeout.tv_sec << "."<<timeout.tv_nsec << endl;
		retcode=pthread_cond_timedwait(&cond,&mutex,&timeout);
		pthread_mutex_unlock(&mutex);

		return retcode!=ETIMEDOUT;
	}
	*/

	Condition::~Condition()
	{
		pthread_mutex_lock(&mutex);
		pthread_cond_destroy(&cond);
		pthread_mutex_unlock(&mutex);
		pthread_mutex_destroy(&mutex);
	}
	
#endif