Initial commit of upstream NSPR (4.7.3) and NSS3 (3.12).

third_party/nspr/mozilla/nsprpub/pr/src/bthreads/btmon.c

Index: third_party/nspr/mozilla/nsprpub/pr/src/bthreads/btmon.c
diff --git a/third_party/nspr/mozilla/nsprpub/pr/src/bthreads/btmon.c b/third_party/nspr/mozilla/nsprpub/pr/src/bthreads/btmon.c
new file mode 100644
index 0000000000000000000000000000000000000000..f14d1379b72ccb67bbf8bc6b658fdf019ec1408a
--- /dev/null
+++ b/third_party/nspr/mozilla/nsprpub/pr/src/bthreads/btmon.c
@@ -0,0 +1,219 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is the Netscape Portable Runtime (NSPR).
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1998-2000
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include <kernel/OS.h>
+
+#include "primpl.h"
+
+/*
+** 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.
+*/
+PR_IMPLEMENT(PRMonitor*)
+    PR_NewMonitor (void)
+{
+    PRMonitor *mon;
+    PRCondVar *cvar;
+    PRLock    *lock;
+
+    mon = PR_NEWZAP( PRMonitor );
+    if( mon )
+    {
+	lock = PR_NewLock();
+	if( !lock )
+        {
+	    PR_DELETE( mon );
+	    return( 0 );
+	}
+
+	cvar = PR_NewCondVar( lock );
+	if( !cvar )
+	{
+	    PR_DestroyLock( lock );
+	    PR_DELETE( mon );
+	    return( 0 );
+	}
+
+	mon->cvar = cvar;
+	mon->name = NULL;
+    }
+
+    return( mon );
+}
+
+PR_IMPLEMENT(PRMonitor*) PR_NewNamedMonitor(const char* name)
+{
+    PRMonitor* mon = PR_NewMonitor();
+    if( mon )
+    {
+        mon->name = name;
+    }
+    return mon;
+}
+
+/*
+** 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.
+**
+*/
+PR_IMPLEMENT(void)
+    PR_DestroyMonitor (PRMonitor *mon)
+{
+    PR_DestroyLock( mon->cvar->lock );
+    PR_DestroyCondVar( mon->cvar );
+    PR_DELETE( 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.
+*/
+PR_IMPLEMENT(void)
+    PR_EnterMonitor (PRMonitor *mon)
+{
+    if( mon->cvar->lock->owner == find_thread( NULL ) )
+    {
+	mon->entryCount++;
+
+    } else
+    {
+	PR_Lock( mon->cvar->lock );
+	mon->entryCount = 1;
+    }
+}
+
+/*
+** 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.
+*/
+PR_IMPLEMENT(PRStatus)
+    PR_ExitMonitor (PRMonitor *mon)
+{
+    if( mon->cvar->lock->owner != find_thread( NULL ) )
+    {
+	return( PR_FAILURE );
+    }
+    if( --mon->entryCount == 0 )
+    {
+	return( PR_Unlock( mon->cvar->lock ) );
+    }
+    return( PR_SUCCESS );
+}
+
+/*
+** 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.
+*/
+PR_IMPLEMENT(PRStatus)
+    PR_Wait (PRMonitor *mon, PRIntervalTime ticks)
+{
+    PRUint32 entryCount;
+    PRUintn  status;
+    PRThread *meThread;
+    thread_id me = find_thread( NULL );
+    meThread = PR_GetCurrentThread();
+
+    if( mon->cvar->lock->owner != me ) return( PR_FAILURE );
+
+    entryCount = mon->entryCount;
+    mon->entryCount = 0;
+
+    status = PR_WaitCondVar( mon->cvar, ticks );
+
+    mon->entryCount = entryCount;
+
+    return( status );
+}
+
+/*
+** 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.
+*/
+PR_IMPLEMENT(PRStatus)
+    PR_Notify (PRMonitor *mon)
+{
+    if( mon->cvar->lock->owner != find_thread( NULL ) )
+    {
+	return( PR_FAILURE );
+    }
+
+    PR_NotifyCondVar( mon->cvar );
+    return( PR_SUCCESS );
+}
+
+/*
+** 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.
+*/
+PR_IMPLEMENT(PRStatus)
+    PR_NotifyAll (PRMonitor *mon)
+{
+    if( mon->cvar->lock->owner != find_thread( NULL ) )
+    {
+	return( PR_FAILURE );
+    }
+
+    PR_NotifyAllCondVar( mon->cvar );
+    return( PR_SUCCESS );
+}
+
+PR_IMPLEMENT(PRIntn)
+    PR_GetMonitorEntryCount(PRMonitor *mon)
+{
+    return( mon->entryCount );
+}
+