diff options
Diffstat (limited to 'mozilla/security/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c')
| -rwxr-xr-x | mozilla/security/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/mozilla/security/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c b/mozilla/security/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c new file mode 100755 index 0000000..cedbdda --- /dev/null +++ b/mozilla/security/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_rwlock.c @@ -0,0 +1,250 @@ +/* ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0/LGPL 2.1 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is the PKIX-C library. + * + * The Initial Developer of the Original Code is + * Sun Microsystems, Inc. + * Portions created by the Initial Developer are + * Copyright 2004-2007 Sun Microsystems, Inc. All Rights Reserved. + * + * Contributor(s): + * Sun Microsystems, Inc. + * + * Alternatively, the contents of this file may be used under the terms of + * either the GNU General Public License Version 2 or later (the "GPL"), or + * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), + * in which case the provisions of the GPL or the LGPL are applicable instead + * of those above. If you wish to allow use of your version of this file only + * under the terms of either the GPL or the LGPL, and not to allow others to + * use your version of this file under the terms of the MPL, indicate your + * decision by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL or the LGPL. If you do not delete + * the provisions above, a recipient may use your version of this file under + * the terms of any one of the MPL, the GPL or the LGPL. + * + * ***** END LICENSE BLOCK ***** */ +/* + * pkix_pl_rwlock.c + * + * Read/Write Lock Functions + * + */ + +#include "pkix_pl_rwlock.h" + +/* --Private-Functions-------------------------------------------- */ + +static PKIX_Error * +pkix_pl_RWLock_Destroy( + PKIX_PL_Object *object, + void *plContext) +{ + PKIX_PL_RWLock* rwlock = NULL; + + PKIX_ENTER(RWLOCK, "pkix_pl_RWLock_Destroy"); + PKIX_NULLCHECK_ONE(object); + + PKIX_CHECK(pkix_CheckType(object, PKIX_RWLOCK_TYPE, plContext), + PKIX_OBJECTNOTRWLOCK); + + rwlock = (PKIX_PL_RWLock*) object; + + PKIX_RWLOCK_DEBUG("Calling PR_DestroyRWLock)\n"); + PR_DestroyRWLock(rwlock->lock); + rwlock->lock = NULL; + +cleanup: + + PKIX_RETURN(RWLOCK); +} + +/* + * FUNCTION: pkix_pl_RWLock_RegisterSelf + * DESCRIPTION: + * Registers PKIX_RWLOCK_TYPE and its related functions with systemClasses[] + * THREAD SAFETY: + * Not Thread Safe - for performance and complexity reasons + * + * Since this function is only called by PKIX_PL_Initialize, which should + * only be called once, it is acceptable that this function is not + * thread-safe. + */ +PKIX_Error * +pkix_pl_RWLock_RegisterSelf( + void *plContext) +{ + + extern pkix_ClassTable_Entry systemClasses[PKIX_NUMTYPES]; + pkix_ClassTable_Entry entry; + + PKIX_ENTER(RWLOCK, "pkix_pl_RWLock_RegisterSelf"); + + entry.description = "RWLock"; + entry.objCounter = 0; + entry.typeObjectSize = sizeof(PKIX_PL_RWLock); + entry.destructor = pkix_pl_RWLock_Destroy; + entry.equalsFunction = NULL; + entry.hashcodeFunction = NULL; + entry.toStringFunction = NULL; + entry.comparator = NULL; + entry.duplicateFunction = NULL; + + systemClasses[PKIX_RWLOCK_TYPE] = entry; + + PKIX_RETURN(RWLOCK); +} + +/* --Public-Functions--------------------------------------------- */ + +PKIX_Error * +PKIX_PL_RWLock_Create( + PKIX_PL_RWLock **pNewLock, + void *plContext) +{ + PKIX_PL_RWLock *rwLock = NULL; + + PKIX_ENTER(RWLOCK, "PKIX_PL_RWLock_Create"); + PKIX_NULLCHECK_ONE(pNewLock); + + PKIX_CHECK(PKIX_PL_Object_Alloc + (PKIX_RWLOCK_TYPE, + sizeof (PKIX_PL_RWLock), + (PKIX_PL_Object **)&rwLock, + plContext), + PKIX_ERRORALLOCATINGRWLOCK); + + PKIX_RWLOCK_DEBUG("\tCalling PR_NewRWLock)\n"); + rwLock->lock = PR_NewRWLock(PR_RWLOCK_RANK_NONE, "PKIX RWLock"); + + if (rwLock->lock == NULL) { + PKIX_DECREF(rwLock); + PKIX_ERROR(PKIX_OUTOFMEMORY); + } + + rwLock->readCount = 0; + rwLock->writeLocked = PKIX_FALSE; + + *pNewLock = rwLock; + +cleanup: + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_AcquireReaderLock( + PKIX_PL_RWLock *lock, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_AcquireReaderLock"); + PKIX_NULLCHECK_ONE(lock); + + PKIX_RWLOCK_DEBUG("\tCalling PR_RWLock_Rlock)\n"); + (void) PR_RWLock_Rlock(lock->lock); + + lock->readCount++; + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_ReleaseReaderLock( + PKIX_PL_RWLock *lock, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_ReleaseReaderLock"); + PKIX_NULLCHECK_ONE(lock); + + PKIX_RWLOCK_DEBUG("\tCalling PR_RWLock_Unlock)\n"); + (void) PR_RWLock_Unlock(lock->lock); + + lock->readCount--; + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_IsReaderLockHeld( + PKIX_PL_RWLock *lock, + PKIX_Boolean *pIsHeld, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_IsReaderLockHeld"); + PKIX_NULLCHECK_TWO(lock, pIsHeld); + + *pIsHeld = (lock->readCount > 0)?PKIX_TRUE:PKIX_FALSE; + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_AcquireWriterLock( + PKIX_PL_RWLock *lock, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_AcquireWriterLock"); + PKIX_NULLCHECK_ONE(lock); + + PKIX_RWLOCK_DEBUG("\tCalling PR_RWLock_Wlock\n"); + (void) PR_RWLock_Wlock(lock->lock); + + if (lock->readCount > 0) { + PKIX_ERROR(PKIX_LOCKHASNONZEROREADCOUNT); + } + + /* We should never acquire a write lock if the lock is held */ + lock->writeLocked = PKIX_TRUE; + +cleanup: + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_ReleaseWriterLock( + PKIX_PL_RWLock *lock, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_ReleaseWriterLock"); + PKIX_NULLCHECK_ONE(lock); + + if (lock->readCount > 0) { + PKIX_ERROR(PKIX_LOCKHASNONZEROREADCOUNT); + } + + PKIX_RWLOCK_DEBUG("\tCalling PR_RWLock_Unlock)\n"); + (void) PR_RWLock_Unlock(lock->lock); + + /* XXX Need to think about thread safety here */ + /* There should be a single lock holder */ + lock->writeLocked = PKIX_FALSE; + +cleanup: + + PKIX_RETURN(RWLOCK); +} + +PKIX_Error * +PKIX_PL_IsWriterLockHeld( + PKIX_PL_RWLock *lock, + PKIX_Boolean *pIsHeld, + void *plContext) +{ + PKIX_ENTER(RWLOCK, "PKIX_PL_IsWriterLockHeld"); + PKIX_NULLCHECK_TWO(lock, pIsHeld); + + *pIsHeld = lock->writeLocked; + + PKIX_RETURN(RWLOCK); +} |