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 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-

  * vim: sw=4 ts=4 et :

  * 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 mozilla_ReentrantMonitor_h

 #define mozilla_ReentrantMonitor_h

 #include "prmon.h"

 #ifdef MOZILLA_INTERNAL_API

 #include "GeckoProfiler.h"

 #endif //MOZILLA_INTERNAL_API

 #include "mozilla/BlockingResourceBase.h"

 //

 // Provides:

 //

 //  - ReentrantMonitor, a Java-like monitor

 //  - ReentrantMonitorAutoEnter, an RAII class for ensuring that

 //    ReentrantMonitors are properly entered and exited

 //

 // Using ReentrantMonitorAutoEnter is MUCH preferred to making bare calls to 

 // ReentrantMonitor.Enter and Exit.

 //

 namespace mozilla {

 /**

  * ReentrantMonitor

  * Java-like monitor.

  * When possible, use ReentrantMonitorAutoEnter to hold this monitor within a

  * scope, instead of calling Enter/Exit directly.

  **/

 class NS_COM_GLUE ReentrantMonitor : BlockingResourceBase

 {

 public:

     /**

      * ReentrantMonitor

      * @param aName A name which can reference this monitor

      */

     ReentrantMonitor(const char* aName) :

         BlockingResourceBase(aName, eReentrantMonitor)

 #ifdef DEBUG

         , mEntryCount(0)

 #endif

     {

         MOZ_COUNT_CTOR(ReentrantMonitor);

         mReentrantMonitor = PR_NewMonitor();

         if (!mReentrantMonitor)

             NS_RUNTIMEABORT("Can't allocate mozilla::ReentrantMonitor");

     }

     /**

      * ~ReentrantMonitor

      **/

     ~ReentrantMonitor()

     {

         NS_ASSERTION(mReentrantMonitor,

                      "improperly constructed ReentrantMonitor or double free");

         PR_DestroyMonitor(mReentrantMonitor);

         mReentrantMonitor = 0;

         MOZ_COUNT_DTOR(ReentrantMonitor);

     }

 #ifndef DEBUG

     /** 

      * Enter

      * @see prmon.h 

      **/

     void Enter()

     {

         PR_EnterMonitor(mReentrantMonitor);

     }

     /** 

      * Exit

      * @see prmon.h 

      **/

     void Exit()

     {

         PR_ExitMonitor(mReentrantMonitor);

     }

     /**

      * Wait

      * @see prmon.h

      **/      

     nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)

     {

 #ifdef MOZILLA_INTERNAL_API

         GeckoProfilerSleepRAII profiler_sleep;

 #endif //MOZILLA_INTERNAL_API

         return PR_Wait(mReentrantMonitor, interval) == PR_SUCCESS ?

             NS_OK : NS_ERROR_FAILURE;

     }

 #else // ifndef DEBUG

     void Enter();

     void Exit();

     nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT);

 #endif  // ifndef DEBUG

     /** 

      * Notify

      * @see prmon.h 

      **/      

     nsresult Notify()

     {

         return PR_Notify(mReentrantMonitor) == PR_SUCCESS

             ? NS_OK : NS_ERROR_FAILURE;

     }

     /** 

      * NotifyAll

      * @see prmon.h 

      **/      

     nsresult NotifyAll()

     {

         return PR_NotifyAll(mReentrantMonitor) == PR_SUCCESS

             ? NS_OK : NS_ERROR_FAILURE;

     }

 #ifdef DEBUG

     /**

      * AssertCurrentThreadIn

      * @see prmon.h

      **/

     void AssertCurrentThreadIn()

     {

         PR_ASSERT_CURRENT_THREAD_IN_MONITOR(mReentrantMonitor);

     }

     /**

      * AssertNotCurrentThreadIn

      * @see prmon.h

      **/

     void AssertNotCurrentThreadIn()

     {

         // FIXME bug 476536

     }

 #else

     void AssertCurrentThreadIn()

     {

     }

     void AssertNotCurrentThreadIn()

     {

     }

 #endif  // ifdef DEBUG

 private:

     ReentrantMonitor();

     ReentrantMonitor(const ReentrantMonitor&);

     ReentrantMonitor& operator =(const ReentrantMonitor&);

     PRMonitor* mReentrantMonitor;

 #ifdef DEBUG

     int32_t mEntryCount;

 #endif

 };

 /**

  * ReentrantMonitorAutoEnter

  * Enters the ReentrantMonitor when it enters scope, and exits it when

  * it leaves scope.

  *

  * MUCH PREFERRED to bare calls to ReentrantMonitor.Enter and Exit.

  */ 

 class NS_COM_GLUE MOZ_STACK_CLASS ReentrantMonitorAutoEnter

 {

 public:

     /**

      * Constructor

      * The constructor aquires the given lock.  The destructor

      * releases the lock.

      * 

      * @param aReentrantMonitor A valid mozilla::ReentrantMonitor*. 

      **/

     ReentrantMonitorAutoEnter(mozilla::ReentrantMonitor &aReentrantMonitor) :

         mReentrantMonitor(&aReentrantMonitor)

     {

         NS_ASSERTION(mReentrantMonitor, "null monitor");

         mReentrantMonitor->Enter();

     }

     ~ReentrantMonitorAutoEnter(void)

     {

         mReentrantMonitor->Exit();

     }

     nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)

     {

        return mReentrantMonitor->Wait(interval);

     }

     nsresult Notify()

     {

         return mReentrantMonitor->Notify();

     }

     nsresult NotifyAll()

     {

         return mReentrantMonitor->NotifyAll();

     }

 private:

     ReentrantMonitorAutoEnter();

     ReentrantMonitorAutoEnter(const ReentrantMonitorAutoEnter&);

     ReentrantMonitorAutoEnter& operator =(const ReentrantMonitorAutoEnter&);

     static void* operator new(size_t) CPP_THROW_NEW;

     static void operator delete(void*);

     mozilla::ReentrantMonitor* mReentrantMonitor;

 };

 /**

  * ReentrantMonitorAutoExit

  * Exit the ReentrantMonitor when it enters scope, and enters it when it leaves

  * scope.

  *

  * MUCH PREFERRED to bare calls to ReentrantMonitor.Exit and Enter.

  */

 class MOZ_STACK_CLASS ReentrantMonitorAutoExit

 {

 public:

     /**

      * Constructor

      * The constructor releases the given lock.  The destructor

      * acquires the lock. The lock must be held before constructing

      * this object!

      *

      * @param aReentrantMonitor A valid mozilla::ReentrantMonitor*. It

      *                 must be already locked.

      **/

     ReentrantMonitorAutoExit(ReentrantMonitor& aReentrantMonitor) :

         mReentrantMonitor(&aReentrantMonitor)

     {

         NS_ASSERTION(mReentrantMonitor, "null monitor");

         mReentrantMonitor->AssertCurrentThreadIn();

         mReentrantMonitor->Exit();

     }

     ~ReentrantMonitorAutoExit(void)

     {

         mReentrantMonitor->Enter();

     }

 private:

     ReentrantMonitorAutoExit();

     ReentrantMonitorAutoExit(const ReentrantMonitorAutoExit&);

     ReentrantMonitorAutoExit& operator =(const ReentrantMonitorAutoExit&);

     static void* operator new(size_t) CPP_THROW_NEW;

     static void operator delete(void*);

     ReentrantMonitor* mReentrantMonitor;

 };

 } // namespace mozilla

 #endif // ifndef mozilla_ReentrantMonitor_h