andre@0: /* This Source Code Form is subject to the terms of the Mozilla Public
andre@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
andre@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
andre@0: /*
andre@0:  * Locking and queue management primatives
andre@0:  *
andre@0:  */
andre@0: 
andre@0: #include "seccomon.h"
andre@0: #include "nssilock.h"
andre@0: #include "secmod.h"
andre@0: #include "secmodi.h"
andre@0: #include "secmodti.h"
andre@0: #include "nssrwlk.h"
andre@0: 
andre@0: /*
andre@0:  * create a new lock for a Module List
andre@0:  */
andre@0: SECMODListLock *SECMOD_NewListLock()
andre@0: {
andre@0:     return NSSRWLock_New( 10, "moduleListLock");
andre@0: }
andre@0: 
andre@0: /*
andre@0:  * destroy the lock
andre@0:  */
andre@0: void SECMOD_DestroyListLock(SECMODListLock *lock) 
andre@0: {
andre@0:     NSSRWLock_Destroy(lock);
andre@0: }
andre@0: 
andre@0: 
andre@0: /*
andre@0:  * Lock the List for Read: NOTE: this assumes the reading isn't so common
andre@0:  * the writing will be starved.
andre@0:  */
andre@0: void SECMOD_GetReadLock(SECMODListLock *modLock) 
andre@0: {
andre@0:     NSSRWLock_LockRead(modLock);
andre@0: }
andre@0: 
andre@0: /*
andre@0:  * Release the Read lock
andre@0:  */
andre@0: void SECMOD_ReleaseReadLock(SECMODListLock *modLock) 
andre@0: {
andre@0:     NSSRWLock_UnlockRead(modLock);
andre@0: }
andre@0: 
andre@0: 
andre@0: /*
andre@0:  * lock the list for Write
andre@0:  */
andre@0: void SECMOD_GetWriteLock(SECMODListLock *modLock) 
andre@0: {
andre@0:     NSSRWLock_LockWrite(modLock);
andre@0: }
andre@0: 
andre@0: 
andre@0: /*
andre@0:  * Release the Write Lock: NOTE, this code is pretty inefficient if you have
andre@0:  * lots of write collisions.
andre@0:  */
andre@0: void SECMOD_ReleaseWriteLock(SECMODListLock *modLock) 
andre@0: {
andre@0:     NSSRWLock_UnlockWrite(modLock);
andre@0: }
andre@0: 
andre@0: 
andre@0: /*
andre@0:  * must Hold the Write lock
andre@0:  */
andre@0: void
andre@0: SECMOD_RemoveList(SECMODModuleList **parent, SECMODModuleList *child) 
andre@0: {
andre@0:     *parent = child->next;
andre@0:     child->next = NULL;
andre@0: }
andre@0: 
andre@0: /*
andre@0:  * if lock is not specified, it must already be held
andre@0:  */
andre@0: void
andre@0: SECMOD_AddList(SECMODModuleList *parent, SECMODModuleList *child, 
andre@0: 							SECMODListLock *lock) 
andre@0: {
andre@0:     if (lock) { SECMOD_GetWriteLock(lock); }
andre@0: 
andre@0:     child->next = parent->next;
andre@0:     parent->next = child;
andre@0: 
andre@0:    if (lock) { SECMOD_ReleaseWriteLock(lock); }
andre@0: }
andre@0: 
andre@0: