summaryrefslogtreecommitdiffstats
path: root/nsprpub/pr/include/obsolete/prsem.h
diff options
context:
space:
mode:
Diffstat (limited to 'nsprpub/pr/include/obsolete/prsem.h')
-rw-r--r--nsprpub/pr/include/obsolete/prsem.h64
1 files changed, 64 insertions, 0 deletions
diff --git a/nsprpub/pr/include/obsolete/prsem.h b/nsprpub/pr/include/obsolete/prsem.h
new file mode 100644
index 0000000000..d1981d2b9b
--- /dev/null
+++ b/nsprpub/pr/include/obsolete/prsem.h
@@ -0,0 +1,64 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef prsem_h___
+#define prsem_h___
+
+/*
+** API for counting semaphores. Semaphores are counting synchronizing
+** variables based on a lock and a condition variable. They are lightweight
+** contention control for a given count of resources.
+*/
+#include "prtypes.h"
+
+PR_BEGIN_EXTERN_C
+
+typedef struct PRSemaphore PRSemaphore;
+
+/*
+** Create a new semaphore object.
+*/
+NSPR_API(PRSemaphore*) PR_NewSem(PRUintn value);
+
+/*
+** Destroy the given semaphore object.
+**
+*/
+NSPR_API(void) PR_DestroySem(PRSemaphore *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.
+*/
+NSPR_API(PRStatus) PR_WaitSem(PRSemaphore *sem);
+
+/*
+** 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.
+*/
+NSPR_API(void) PR_PostSem(PRSemaphore *sem);
+
+/*
+** Returns the value of the semaphore referenced by sem without affecting
+** the state of the semaphore. The value represents the semaphore vaule
+F** at the time of the call, but may not be the actual value when the
+** caller inspects it.
+*/
+NSPR_API(PRUintn) PR_GetValueSem(PRSemaphore *sem);
+
+PR_END_EXTERN_C
+
+#endif /* prsem_h___ */