Symaptic: os/ossrv/genericopenlibs/openenvcore/libpthread/src/mutex.cpp@bde4ae8d615e (annotated)

sl@0	1	// Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0	2	// All rights reserved.
sl@0	3	// This component and the accompanying materials are made available
sl@0	4	// under the terms of "Eclipse Public License v1.0"
sl@0	5	// which accompanies this distribution, and is available
sl@0	6	// at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0	7	//
sl@0	8	// Initial Contributors:
sl@0	9	// Nokia Corporation - initial contribution.
sl@0	10	//
sl@0	11	// Contributors:
sl@0	12	//
sl@0	13	// Description:
sl@0	14	// Name : mutex.cpp
sl@0	15	// Part of : pthread
sl@0	16	// Interface : POSIX, pthread
sl@0	17	// POSIX implementation of mutexes on Symbian
sl@0	18	// Version :
sl@0	19	//
sl@0	20
sl@0	21
sl@0	22
sl@0	23	#include "mutextypes.h"
sl@0	24
sl@0	25	/*
sl@0	26	This function waits on the aLock semaphore.
sl@0	27	*/
sl@0	28	int _doWait(RSemaphore* aLock, const struct timespec *abstime)
sl@0	29	{
sl@0	30	int retval = 0;
sl@0	31	if(!abstime)
sl@0	32	{
sl@0	33	aLock->Wait();
sl@0	34	}
sl@0	35	else
sl@0	36	{
sl@0	37	long lSleepTime = _microsleeptime(abstime);
sl@0	38	if(lSleepTime <0)
sl@0	39	{
sl@0	40	if (EINVAL == errno)
sl@0	41	{
sl@0	42	errno = 0;
sl@0	43	return EINVAL;
sl@0	44	}
sl@0	45	else if(ETIMEDOUT == errno)
sl@0	46	{
sl@0	47	errno = 0;
sl@0	48	return ETIMEDOUT;
sl@0	49	}
sl@0	50
sl@0	51	}
sl@0	52
sl@0	53	retval = aLock->Wait(lSleepTime);
sl@0	54	if(retval != KErrNone)
sl@0	55	{
sl@0	56	return ETIMEDOUT;
sl@0	57	}
sl@0	58
sl@0	59	}
sl@0	60	return 0;
sl@0	61	}
sl@0	62
sl@0	63	/*
sl@0	64	This internal function destroys the mutex object.
sl@0	65	*/
sl@0	66	void _closeMutex(pthread_mutex_t* mutex)
sl@0	67	{
sl@0	68	_pthread_mutex_t* pMutex = mutex->iPtr;
sl@0	69	if(pMutex)
sl@0	70	{
sl@0	71	if(pMutex->iSemaphoreCreated)
sl@0	72	{
sl@0	73	pMutex->iSignalSemaphore.Close();
sl@0	74	}
sl@0	75	if(pMutex->iDataLockCreated)
sl@0	76	{
sl@0	77	pMutex->iDataLock.Close();
sl@0	78	}
sl@0	79	mutex->iPtr = NULL;
sl@0	80	delete pMutex;
sl@0	81	}
sl@0	82	return;
sl@0	83	}
sl@0	84
sl@0	85	int _mutexCreate (pthread_mutex_t * mutex,
sl@0	86	const pthread_mutexattr_t* attr)
sl@0	87	{
sl@0	88
sl@0	89	if( attr->iSharedType != PTHREAD_PROCESS_PRIVATE)
sl@0	90	{
sl@0	91	return ENOSYS;
sl@0	92	}
sl@0	93
sl@0	94	mutex->iState = _EInvalid;
sl@0	95	_pthread_mutex_t* pMutex = new _pthread_mutex_t;
sl@0	96	mutex->iPtr = pMutex;
sl@0	97	if(!pMutex)
sl@0	98	{
sl@0	99	return ENOMEM;
sl@0	100	}
sl@0	101
sl@0	102	pMutex->iSharedType = attr->iSharedType;
sl@0	103	pMutex->iMutexType = attr->iMutexType;
sl@0	104	pMutex->iDataLockCreated = false;
sl@0	105	pMutex->iSemaphoreCreated = false;
sl@0	106
sl@0	107	if(pMutex->iSignalSemaphore.CreateLocal(1) != KErrNone)
sl@0	108	{
sl@0	109	_closeMutex(mutex);
sl@0	110	return EAGAIN;
sl@0	111	}
sl@0	112	pMutex->iSemaphoreCreated = true;
sl@0	113
sl@0	114	if(pMutex->iDataLock.CreateLocal() != KErrNone)
sl@0	115	{
sl@0	116	_closeMutex(mutex);
sl@0	117	return EAGAIN;
sl@0	118	}
sl@0	119	pMutex->iDataLockCreated = true;
sl@0	120
sl@0	121	pMutex->iCount = 0;
sl@0	122	pMutex->iSemaphoreState = SEM_FREE;
sl@0	123	pMutex->iLockingThread = 0;
sl@0	124	mutex->iState = _EInitialized;
sl@0	125	return 0;
sl@0	126	}
sl@0	127
sl@0	128
sl@0	129	/*
sl@0	130	This function is an internal harness function used to resolve the race to dynamically initialize a static mutex
sl@0	131	*/
sl@0	132	bool _InitOnce(pthread_mutex_t* mutex)
sl@0	133	{
sl@0	134
sl@0	135	pthread_mutexattr_t defaultattributes =
sl@0	136	PTHREAD_MUTEX_ATTRIBUTE_DEFAULT_INITIALIZER;
sl@0	137	pthread_mutexattr_t recursiveattributes =
sl@0	138	PTHREAD_MUTEX_ATTRIBUTE_RECURSIVE_INITIALIZER;
sl@0	139	pthread_mutexattr_t errorcheckattributes =
sl@0	140	PTHREAD_MUTEX_ATTRIBUTE_ERRORCHECK_INITIALIZER;
sl@0	141
sl@0	142	if(mutex->iState == _EInitialized)
sl@0	143	{
sl@0	144	return true;
sl@0	145	}
sl@0	146
sl@0	147	mutex->iReentry = 0xBABA;
sl@0	148
sl@0	149	pthread_mutexattr_t* attr;
sl@0	150	switch(mutex->iState)
sl@0	151	{
sl@0	152	case _ENeedsNormalInit:
sl@0	153	{
sl@0	154	attr = &defaultattributes;
sl@0	155	break;
sl@0	156	}
sl@0	157
sl@0	158	case _ENeedsRecursiveInit:
sl@0	159	{
sl@0	160	attr = &recursiveattributes;
sl@0	161	break;
sl@0	162	}
sl@0	163
sl@0	164	case _ENeedsErrorCheckInit:
sl@0	165	{
sl@0	166	attr = &errorcheckattributes;
sl@0	167	break;
sl@0	168	}
sl@0	169
sl@0	170	default:
sl@0	171	return false;
sl@0	172	}
sl@0	173
sl@0	174	#ifndef NOUSE_INTERNALS
sl@0	175	void* tlsPtr;
sl@0	176
sl@0	177	// Get the TLS pointer
sl@0	178	tlsPtr = _pthread_getTls();
sl@0	179
sl@0	180	if(!tlsPtr)
sl@0	181	{
sl@0	182	return false;
sl@0	183	}
sl@0	184	#endif
sl@0	185
sl@0	186	int retval=0;
sl@0	187	#ifndef NOUSE_INTERNALS
sl@0	188	_pthread_atomicMutexLock(tlsPtr);
sl@0	189	#endif
sl@0	190	if(mutex->iState != _EInitialized)
sl@0	191	{
sl@0	192	retval = _mutexCreate(mutex,attr);
sl@0	193	}
sl@0	194	#ifndef NOUSE_INTERNALS
sl@0	195	_pthread_atomicMutexUnlock(tlsPtr);
sl@0	196	#endif
sl@0	197
sl@0	198	if(retval == 0)
sl@0	199	{
sl@0	200	return true;
sl@0	201	}
sl@0	202	else
sl@0	203	{
sl@0	204	return false;
sl@0	205	}
sl@0	206	}
sl@0	207
sl@0	208
sl@0	209	/*
sl@0	210	This function is an internal function used to provide the POSIX mutex lock
sl@0	211	functionality.
sl@0	212	*/
sl@0	213	int _internalMutexLock(pthread_mutex_t * mutex,const struct timespec *abstime)
sl@0	214	{
sl@0	215	if( !VALID_MUTEX(mutex) )
sl@0	216	{
sl@0	217	return EINVAL;
sl@0	218	}
sl@0	219
sl@0	220	_pthread_mutex_t* pMutex = mutex->iPtr;
sl@0	221
sl@0	222
sl@0	223	int retval = 0;
sl@0	224	pthread_t self;
sl@0	225	switch(pMutex->iMutexType)
sl@0	226	{
sl@0	227	case PTHREAD_MUTEX_NORMAL:
sl@0	228	{
sl@0	229	self = pthread_self();
sl@0	230	pMutex->iDataLock.Wait();
sl@0	231	if(mutex->iState == _EDestroyed)
sl@0	232	{
sl@0	233	pMutex->iDataLock.Signal();
sl@0	234	return EINVAL;
sl@0	235	}
sl@0	236	pMutex->iSemaphoreState++;
sl@0	237	pMutex->iDataLock.Signal();
sl@0	238
sl@0	239	retval = _doWait(&pMutex->iSignalSemaphore,abstime);
sl@0	240	if(retval == 0)
sl@0	241	{
sl@0	242	pMutex->iDataLock.Wait();
sl@0	243	if(mutex->iState == _EDestroyed)
sl@0	244	{
sl@0	245	pMutex->iDataLock.Signal();
sl@0	246	return EINVAL;
sl@0	247	}
sl@0	248	pMutex->iLockingThread = self;
sl@0	249	pMutex->iDataLock.Signal();
sl@0	250	}
sl@0	251	break;
sl@0	252	}
sl@0	253
sl@0	254	case PTHREAD_MUTEX_RECURSIVE:
sl@0	255
sl@0	256	{
sl@0	257	self = pthread_self();
sl@0	258	if(pMutex->iLockingThread == self)
sl@0	259	{
sl@0	260	pMutex->iDataLock.Wait();
sl@0	261	if(mutex->iState == _EDestroyed)
sl@0	262	{
sl@0	263	pMutex->iDataLock.Signal();
sl@0	264	return EINVAL;
sl@0	265	}
sl@0	266	pMutex->iCount++;
sl@0	267	pMutex->iDataLock.Signal();
sl@0	268	}
sl@0	269	else
sl@0	270	{
sl@0	271	pMutex->iDataLock.Wait();
sl@0	272	if(mutex->iState == _EDestroyed)
sl@0	273	{
sl@0	274	pMutex->iDataLock.Signal();
sl@0	275	return EINVAL;
sl@0	276	}
sl@0	277	pMutex->iSemaphoreState++;
sl@0	278	pMutex->iDataLock.Signal();
sl@0	279
sl@0	280	retval = _doWait(&pMutex->iSignalSemaphore,abstime);
sl@0	281	if(retval == 0)
sl@0	282	{
sl@0	283	pMutex->iDataLock.Wait();
sl@0	284	if(mutex->iState == _EDestroyed)
sl@0	285	{
sl@0	286	pMutex->iDataLock.Signal();
sl@0	287	return EINVAL;
sl@0	288	}
sl@0	289	pMutex->iCount = 1;
sl@0	290	pMutex->iLockingThread = self;
sl@0	291	pMutex->iDataLock.Signal();
sl@0	292	}
sl@0	293	}
sl@0	294	break;
sl@0	295	}
sl@0	296
sl@0	297	case PTHREAD_MUTEX_ERRORCHECK:
sl@0	298	{
sl@0	299	self = pthread_self();
sl@0	300	if(pMutex->iLockingThread == self)
sl@0	301	{
sl@0	302	return EDEADLK;
sl@0	303	}
sl@0	304	else
sl@0	305	{
sl@0	306	pMutex->iDataLock.Wait();
sl@0	307	if(mutex->iState == _EDestroyed)
sl@0	308	{
sl@0	309	pMutex->iDataLock.Signal();
sl@0	310	return EINVAL;
sl@0	311	}
sl@0	312	pMutex->iSemaphoreState++;
sl@0	313	pMutex->iDataLock.Signal();
sl@0	314
sl@0	315	retval = _doWait(&pMutex->iSignalSemaphore,abstime);
sl@0	316	if(retval == 0)
sl@0	317	{
sl@0	318	pMutex->iDataLock.Wait();
sl@0	319	if(mutex->iState == _EDestroyed)
sl@0	320	{
sl@0	321	pMutex->iDataLock.Signal();
sl@0	322	return EINVAL;
sl@0	323	}
sl@0	324	pMutex->iLockingThread = self;
sl@0	325	pMutex->iDataLock.Signal();
sl@0	326	}
sl@0	327	}
sl@0	328	break;
sl@0	329	}
sl@0	330
sl@0	331	default:
sl@0	332	retval = ENOSYS;
sl@0	333	break;
sl@0	334
sl@0	335	}
sl@0	336	return retval;
sl@0	337
sl@0	338	}
sl@0	339
sl@0	340	//End of File

author	sl@SLION-WIN7.fritz.box
	Fri, 15 Jun 2012 03:10:57 +0200
changeset 0	bde4ae8d615e
permissions	-rw-r--r--