scummvm/backends/platform/psp/thread.cpp

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL: https://scummvm.svn.sourceforge.net/svnroot/scummvm/scummvm/trunk/backends/platform/psp/osys_psp.h $
 * $Id: osys_psp.h 49173 2010-05-24 03:05:17Z bluddy $
 *
 */

#include <time.h> 
#include <psptypes.h>
#include <psprtc.h>
#include <pspthreadman.h> 

#include "backends/platform/psp/thread.h"
#include "backends/platform/psp/trace.h"
 
// Class PspThread -------------------------------------------------- 
 
void PspThread::delayMillis(uint32 ms) {
	sceKernelDelayThread(ms * 1000);
}

void PspThread::delayMicros(uint32 us) {
	sceKernelDelayThread(us);
}

// Class PspSemaphore ------------------------------------------------
//#define __PSP_DEBUG_FUNCS__	/* For debugging function calls */
//#define __PSP_DEBUG_PRINT__	/* For debug printouts */

#include "backends/platform/psp/trace.h"

PspSemaphore::PspSemaphore(int initialValue, int maxValue/*=255*/) {
	DEBUG_ENTER_FUNC();
	_handle = 0;
	_handle = (uint32)sceKernelCreateSema("ScummVM Sema", 0 /* attr */, 
								  initialValue, maxValue, 
								  0 /*option*/);
	if (!_handle)
		PSP_ERROR("failed to create semaphore.\n");
}

PspSemaphore::~PspSemaphore() {
	DEBUG_ENTER_FUNC();
	if (_handle)
		if (sceKernelDeleteSema((SceUID)_handle) < 0)
			PSP_ERROR("failed to delete semaphore.\n");
}

int PspSemaphore::numOfWaitingThreads() {
	DEBUG_ENTER_FUNC();
	SceKernelSemaInfo info;
	info.numWaitThreads = 0;
	
	if (sceKernelReferSemaStatus((SceUID)_handle, &info) < 0)
		PSP_ERROR("failed to retrieve semaphore info for handle %d\n", _handle);
		
	return info.numWaitThreads;
}

int PspSemaphore::getValue() {
	DEBUG_ENTER_FUNC();
	SceKernelSemaInfo info;
	info.currentCount = 0;
	
	if (sceKernelReferSemaStatus((SceUID)_handle, &info) < 0)
		PSP_ERROR("failed to retrieve semaphore info for handle %d\n", _handle);
		
	return info.currentCount;
}

bool PspSemaphore::pollForValue(int value) {
	DEBUG_ENTER_FUNC();
	if (sceKernelPollSema((SceUID)_handle, value) < 0)
		return false;
	
	return true;
}

// false: timeout or error
bool PspSemaphore::takeWithTimeOut(uint32 timeOut) {
	DEBUG_ENTER_FUNC();
	
	uint32 *pTimeOut = 0;
	if (timeOut) 
		pTimeOut = &timeOut;
	
	if (sceKernelWaitSema(_handle, 1, pTimeOut) < 0)	// we always wait for 1
		return false;
	return true;
}

bool PspSemaphore::give(int num /*=1*/) {
	DEBUG_ENTER_FUNC();
	
	if (sceKernelSignalSema((SceUID)_handle, num) < 0)
		return false;	
	return true;
}

// Class PspMutex ------------------------------------------------------------

bool PspMutex::lock() {
	DEBUG_ENTER_FUNC();
	int threadId = sceKernelGetThreadId();
	bool ret = true;
	
	if (_ownerId == threadId) {
		_recursiveCount++;
	} else {
		ret = _semaphore.take();
		_ownerId = threadId;
		_recursiveCount = 0;
	}
	return ret;
}

bool PspMutex::unlock() {
	DEBUG_ENTER_FUNC();
	int threadId = sceKernelGetThreadId();
	bool ret = true;
	
	if (_ownerId != threadId) {
		PSP_ERROR("attempt to unlock mutex by thread[%x] as opposed to owner[%x]\n",
			threadId, _ownerId);
		return false;
	}
	
	if (_recursiveCount) {
		_recursiveCount--;
	} else {
		_ownerId = 0;
		ret = _semaphore.give(1);
	}	
	return ret;
}

// Class PspCondition -------------------------------------------------

// Release all threads waiting on the condition
void PspCondition::releaseAll() {
        _mutex.lock();
        if (_waitingThreads > _signaledThreads) {	// we have signals to issue
                int numWaiting = _waitingThreads - _signaledThreads;	// threads we haven't signaled
                _signaledThreads = _waitingThreads;
                
				_waitSem.give(numWaiting);
                _mutex.unlock();
                for (int i=0; i<numWaiting; i++)	// wait for threads to tell us they're awake
					_doneSem.take();
        } else {
                _mutex.unlock();
        }
}

// Mutex must be taken before entering wait
void PspCondition::wait(PspMutex &externalMutex) {
        _mutex.lock();
        _waitingThreads++;
        _mutex.unlock();

        externalMutex.unlock();	// must unlock external mutex

		_waitSem.take();	// sleep on the wait semaphore

		// let the signaling thread know we're done
		_mutex.lock();
        if (_signaledThreads > 0 ) {
                _doneSem.give();	// let the thread know
                _signaledThreads--;
        }
        _waitingThreads--;
        _mutex.unlock();

        externalMutex.lock();		// must lock external mutex here for continuation
}

//#define __PSP_DEBUG_FUNCS__	/* For debugging function calls */
//#define __PSP_DEBUG_PRINT__	/* For debug printouts */

#include "backends/platform/psp/trace.h"


// Class PspRtc ---------------------------------------------------------------

void PspRtc::init() {						// init our starting ticks
	uint32 ticks[2];
	sceRtcGetCurrentTick((u64 *)ticks);

	_startMillis = ticks[0]/1000;
	_startMicros = ticks[0];
	//_lastMillis = ticks[0]/1000;	//debug - only when we don't subtract startMillis
}

#define MS_LOOP_AROUND 4294967				/* We loop every 2^32 / 1000 = 71 minutes */
#define MS_LOOP_CHECK  60000				/* Threading can cause weird mixups without this */

// Note that after we fill up 32 bits ie 50 days we'll loop back to 0, which may cause 
// unpredictable results
uint32 PspRtc::getMillis() {
	uint32 ticks[2];
	
	sceRtcGetCurrentTick((u64 *)ticks);		// can introduce weird thread delays
	
	uint32 millis = ticks[0]/1000;
	millis -= _startMillis;					// get ms since start of program

	if ((int)_lastMillis - (int)millis > MS_LOOP_CHECK) {		// we must have looped around
		if (_looped == false) {					// check to make sure threads do this once
			_looped = true;
			_milliOffset += MS_LOOP_AROUND;		// add the needed offset
			PSP_DEBUG_PRINT("looping around. last ms[%d], curr ms[%d]\n", _lastMillis, millis);
		}	
	} else {
		_looped = false;
	}
	
	_lastMillis = millis;	
	
	return millis + _milliOffset;
}

uint32 PspRtc::getMicros() {
	uint32 ticks[2];
	
	sceRtcGetCurrentTick((u64 *)ticks);
	ticks[0] -= _startMicros;
	
	return ticks[0]; 
}