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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /nsprpub/pr/src/bthreads/btsem.c
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'nsprpub/pr/src/bthreads/btsem.c')
-rw-r--r--nsprpub/pr/src/bthreads/btsem.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/nsprpub/pr/src/bthreads/btsem.c b/nsprpub/pr/src/bthreads/btsem.c
new file mode 100644
index 000000000..011ee6bd3
--- /dev/null
+++ b/nsprpub/pr/src/bthreads/btsem.c
@@ -0,0 +1,98 @@
+/* -*- 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 semaphore object.
+*/
+PR_IMPLEMENT(PRSemaphore*)
+ PR_NewSem (PRUintn value)
+{
+ PRSemaphore *semaphore;
+
+ if (!_pr_initialized) _PR_ImplicitInitialization();
+
+ semaphore = PR_NEWZAP(PRSemaphore);
+ if (NULL != semaphore) {
+ if ((semaphore->sem = create_sem(value, "nspr_sem")) < B_NO_ERROR)
+ return NULL;
+ else
+ return semaphore;
+ }
+ return NULL;
+}
+
+/*
+** Destroy the given semaphore object.
+**
+*/
+PR_IMPLEMENT(void)
+ PR_DestroySem (PRSemaphore *sem)
+{
+ status_t result;
+
+ PR_ASSERT(sem != NULL);
+ result = delete_sem(sem->sem);
+ PR_ASSERT(result == B_NO_ERROR);
+ PR_DELETE(sem);
+}
+
+/*
+** Wait on a Semaphore.
+**
+** This routine allows a calling thread to wait or proceed depending upon
+** the state of the semahore sem. The thread can proceed only if the
+** counter value of the semaphore sem is currently greater than 0. If the
+** value of semaphore sem is positive, it is decremented by one and the
+** routine returns immediately allowing the calling thread to continue. If
+** the value of semaphore sem is 0, the calling thread blocks awaiting the
+** semaphore to be released by another thread.
+**
+** This routine can return PR_PENDING_INTERRUPT if the waiting thread
+** has been interrupted.
+*/
+PR_IMPLEMENT(PRStatus)
+ PR_WaitSem (PRSemaphore *sem)
+{
+ PR_ASSERT(sem != NULL);
+ if (acquire_sem(sem->sem) == B_NO_ERROR)
+ return PR_SUCCESS;
+ else
+ return PR_FAILURE;
+}
+
+/*
+** This routine increments the counter value of the semaphore. If other
+** threads are blocked for the semaphore, then the scheduler will
+** determine which ONE thread will be unblocked.
+*/
+PR_IMPLEMENT(void)
+ PR_PostSem (PRSemaphore *sem)
+{
+ status_t result;
+
+ PR_ASSERT(sem != NULL);
+ result = release_sem_etc(sem->sem, 1, B_DO_NOT_RESCHEDULE);
+ PR_ASSERT(result == B_NO_ERROR);
+}
+
+/*
+** Returns the value of the semaphore referenced by sem without affecting
+** the state of the semaphore. The value represents the semaphore value
+** at the time of the call, but may not be the actual value when the
+** caller inspects it.
+*/
+PR_IMPLEMENT(PRUintn)
+ PR_GetValueSem (PRSemaphore *sem)
+{
+ sem_info info;
+
+ PR_ASSERT(sem != NULL);
+ get_sem_info(sem->sem, &info);
+ return info.count;
+}