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-rw-r--r--nsprpub/pr/src/bthreads/btcvar.c244
1 files changed, 0 insertions, 244 deletions
diff --git a/nsprpub/pr/src/bthreads/btcvar.c b/nsprpub/pr/src/bthreads/btcvar.c
deleted file mode 100644
index c74837907..000000000
--- a/nsprpub/pr/src/bthreads/btcvar.c
+++ /dev/null
@@ -1,244 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-#include <kernel/OS.h>
-
-#include "primpl.h"
-
-/*
-** Create a new condition variable.
-**
-** "lock" is the lock used to protect the condition variable.
-**
-** Condition variables are synchronization objects that threads can use
-** to wait for some condition to occur.
-**
-** This may fail if memory is tight or if some operating system resource
-** is low. In such cases, a NULL will be returned.
-*/
-PR_IMPLEMENT(PRCondVar*)
- PR_NewCondVar (PRLock *lock)
-{
- PRCondVar *cv = PR_NEW( PRCondVar );
- PR_ASSERT( NULL != lock );
- if( NULL != cv )
- {
- cv->lock = lock;
- cv->sem = create_sem(0, "CVSem");
- cv->handshakeSem = create_sem(0, "CVHandshake");
- cv->signalSem = create_sem( 0, "CVSignal");
- cv->signalBenCount = 0;
- cv->ns = cv->nw = 0;
- PR_ASSERT( cv->sem >= B_NO_ERROR );
- PR_ASSERT( cv->handshakeSem >= B_NO_ERROR );
- PR_ASSERT( cv->signalSem >= B_NO_ERROR );
- }
- return cv;
-} /* PR_NewCondVar */
-
-/*
-** Destroy a condition variable. There must be no thread
-** waiting on the condvar. The caller is responsible for guaranteeing
-** that the condvar is no longer in use.
-**
-*/
-PR_IMPLEMENT(void)
- PR_DestroyCondVar (PRCondVar *cvar)
-{
- status_t result = delete_sem( cvar->sem );
- PR_ASSERT( result == B_NO_ERROR );
-
- result = delete_sem( cvar->handshakeSem );
- PR_ASSERT( result == B_NO_ERROR );
-
- result = delete_sem( cvar->signalSem );
- PR_ASSERT( result == B_NO_ERROR );
-
- PR_DELETE( cvar );
-}
-
-/*
-** The thread that waits on a condition is blocked in a "waiting on
-** condition" state until another thread notifies the condition or a
-** caller specified amount of time expires. The lock associated with
-** the condition variable will be released, which must have be held
-** prior to the call to wait.
-**
-** Logically a notified thread is moved from the "waiting on condition"
-** state and made "ready." When scheduled, it will attempt to reacquire
-** the lock that it held when wait was called.
-**
-** The timeout has two well known values, PR_INTERVAL_NO_TIMEOUT and
-** PR_INTERVAL_NO_WAIT. The former value requires that a condition be
-** notified (or the thread interrupted) before it will resume from the
-** wait. If the timeout has a value of PR_INTERVAL_NO_WAIT, the effect
-** is to release the lock, possibly causing a rescheduling within the
-** runtime, then immediately attempting to reacquire the lock and resume.
-**
-** Any other value for timeout will cause the thread to be rescheduled
-** either due to explicit notification or an expired interval. The latter
-** must be determined by treating time as one part of the monitored data
-** being protected by the lock and tested explicitly for an expired
-** interval.
-**
-** Returns PR_FAILURE if the caller has not locked the lock associated
-** with the condition variable or the thread was interrupted (PR_Interrupt()).
-** The particular reason can be extracted with PR_GetError().
-*/
-PR_IMPLEMENT(PRStatus)
- PR_WaitCondVar (PRCondVar *cvar, PRIntervalTime timeout)
-{
- status_t err;
- if( timeout == PR_INTERVAL_NO_WAIT )
- {
- PR_Unlock( cvar->lock );
- PR_Lock( cvar->lock );
- return PR_SUCCESS;
- }
-
- if( atomic_add( &cvar->signalBenCount, 1 ) > 0 )
- {
- if (acquire_sem(cvar->signalSem) == B_INTERRUPTED)
- {
- atomic_add( &cvar->signalBenCount, -1 );
- return PR_FAILURE;
- }
- }
- cvar->nw += 1;
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
-
- PR_Unlock( cvar->lock );
- if( timeout==PR_INTERVAL_NO_TIMEOUT )
- {
- err = acquire_sem(cvar->sem);
- }
- else
- {
- err = acquire_sem_etc(cvar->sem, 1, B_RELATIVE_TIMEOUT, PR_IntervalToMicroseconds(timeout) );
- }
-
- if( atomic_add( &cvar->signalBenCount, 1 ) > 0 )
- {
- while (acquire_sem(cvar->signalSem) == B_INTERRUPTED);
- }
-
- if (cvar->ns > 0)
- {
- release_sem_etc(cvar->handshakeSem, 1, B_DO_NOT_RESCHEDULE);
- cvar->ns -= 1;
- }
- cvar->nw -= 1;
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
-
- PR_Lock( cvar->lock );
- if(err!=B_NO_ERROR)
- {
- return PR_FAILURE;
- }
- return PR_SUCCESS;
-}
-
-/*
-** Notify ONE thread that is currently waiting on 'cvar'. Which thread is
-** dependent on the implementation of the runtime. Common sense would dictate
-** that all threads waiting on a single condition have identical semantics,
-** therefore which one gets notified is not significant.
-**
-** The calling thead must hold the lock that protects the condition, as
-** well as the invariants that are tightly bound to the condition, when
-** notify is called.
-**
-** Returns PR_FAILURE if the caller has not locked the lock associated
-** with the condition variable.
-*/
-PR_IMPLEMENT(PRStatus)
- PR_NotifyCondVar (PRCondVar *cvar)
-{
- status_t err ;
- if( atomic_add( &cvar->signalBenCount, 1 ) > 0 )
- {
- if (acquire_sem(cvar->signalSem) == B_INTERRUPTED)
- {
- atomic_add( &cvar->signalBenCount, -1 );
- return PR_FAILURE;
- }
- }
- if (cvar->nw > cvar->ns)
- {
- cvar->ns += 1;
- release_sem_etc(cvar->sem, 1, B_DO_NOT_RESCHEDULE);
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
-
- while (acquire_sem(cvar->handshakeSem) == B_INTERRUPTED)
- {
- err = B_INTERRUPTED;
- }
- }
- else
- {
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
- }
- return PR_SUCCESS;
-}
-
-/*
-** Notify all of the threads waiting on the condition variable. The order
-** that the threads are notified is indeterminant. The lock that protects
-** the condition must be held.
-**
-** Returns PR_FAILURE if the caller has not locked the lock associated
-** with the condition variable.
-*/
-PR_IMPLEMENT(PRStatus)
- PR_NotifyAllCondVar (PRCondVar *cvar)
-{
- int32 handshakes;
- status_t err = B_OK;
-
- if( atomic_add( &cvar->signalBenCount, 1 ) > 0 )
- {
- if (acquire_sem(cvar->signalSem) == B_INTERRUPTED)
- {
- atomic_add( &cvar->signalBenCount, -1 );
- return PR_FAILURE;
- }
- }
-
- if (cvar->nw > cvar->ns)
- {
- handshakes = cvar->nw - cvar->ns;
- cvar->ns = cvar->nw;
- release_sem_etc(cvar->sem, handshakes, B_DO_NOT_RESCHEDULE);
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
-
- while (acquire_sem_etc(cvar->handshakeSem, handshakes, 0, 0) == B_INTERRUPTED)
- {
- err = B_INTERRUPTED;
- }
- }
- else
- {
- if( atomic_add( &cvar->signalBenCount, -1 ) > 1 )
- {
- release_sem_etc(cvar->signalSem, 1, B_DO_NOT_RESCHEDULE);
- }
- }
- return PR_SUCCESS;
-}
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