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-rw-r--r--nsprpub/pr/include/prmon.h96
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diff --git a/nsprpub/pr/include/prmon.h b/nsprpub/pr/include/prmon.h
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+/* -*- 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 prmon_h___
+#define prmon_h___
+
+#include "prtypes.h"
+#include "prinrval.h"
+
+PR_BEGIN_EXTERN_C
+
+typedef struct PRMonitor PRMonitor;
+
+/*
+** Create a new monitor. Monitors are re-entrant locks with a single built-in
+** condition variable.
+**
+** This may fail if memory is tight or if some operating system resource
+** is low.
+*/
+NSPR_API(PRMonitor*) PR_NewMonitor(void);
+
+/*
+** Destroy a monitor. The caller is responsible for guaranteeing that the
+** monitor is no longer in use. There must be no thread waiting on the monitor's
+** condition variable and that the lock is not held.
+**
+*/
+NSPR_API(void) PR_DestroyMonitor(PRMonitor *mon);
+
+/*
+** Enter the lock associated with the monitor. If the calling thread currently
+** is in the monitor, the call to enter will silently succeed. In either case,
+** it will increment the entry count by one.
+*/
+NSPR_API(void) PR_EnterMonitor(PRMonitor *mon);
+
+/*
+** Decrement the entry count associated with the monitor. If the decremented
+** entry count is zero, the monitor is exited. Returns PR_FAILURE if the
+** calling thread has not entered the monitor.
+*/
+NSPR_API(PRStatus) PR_ExitMonitor(PRMonitor *mon);
+
+/*
+** Wait for a notify on the monitor's condition variable. Sleep for "ticks"
+** amount of time (if "ticks" is PR_INTERVAL_NO_TIMEOUT then the sleep is
+** indefinite).
+**
+** While the thread is waiting it exits the monitor (as if it called
+** PR_ExitMonitor as many times as it had called PR_EnterMonitor). When
+** the wait has finished the thread regains control of the monitors lock
+** with the same entry count as before the wait began.
+**
+** The thread waiting on the monitor will be resumed when the monitor is
+** notified (assuming the thread is the next in line to receive the
+** notify) or when the "ticks" timeout elapses.
+**
+** Returns PR_FAILURE if the caller has not entered the monitor.
+*/
+NSPR_API(PRStatus) PR_Wait(PRMonitor *mon, PRIntervalTime ticks);
+
+/*
+** Notify a thread waiting on the monitor's condition variable. If a thread
+** is waiting on the condition variable (using PR_Wait) then it is awakened
+** and attempts to reenter the monitor.
+*/
+NSPR_API(PRStatus) PR_Notify(PRMonitor *mon);
+
+/*
+** Notify all of the threads waiting on the monitor's condition variable.
+** All of threads waiting on the condition are scheduled to reenter the
+** monitor.
+*/
+NSPR_API(PRStatus) PR_NotifyAll(PRMonitor *mon);
+
+/*
+** PR_ASSERT_CURRENT_THREAD_IN_MONITOR
+** If the current thread is in |mon|, this assertion is guaranteed to
+** succeed. Otherwise, the behavior of this function is undefined.
+*/
+#if defined(DEBUG) || defined(FORCE_PR_ASSERT)
+#define PR_ASSERT_CURRENT_THREAD_IN_MONITOR(/* PRMonitor* */ mon) \
+ PR_AssertCurrentThreadInMonitor(mon)
+#else
+#define PR_ASSERT_CURRENT_THREAD_IN_MONITOR(/* PRMonitor* */ mon)
+#endif
+
+/* Don't call this function directly. */
+NSPR_API(void) PR_AssertCurrentThreadInMonitor(PRMonitor *mon);
+
+PR_END_EXTERN_C
+
+#endif /* prmon_h___ */