michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  * vim: sw=2 ts=8 et :
michael@0:  */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_Monitor_h
michael@0: #define mozilla_Monitor_h
michael@0: 
michael@0: #include "mozilla/CondVar.h"
michael@0: #include "mozilla/Mutex.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: /**
michael@0:  * Monitor provides a *non*-reentrant monitor: *not* a Java-style
michael@0:  * monitor.  If your code needs support for reentrancy, use
michael@0:  * ReentrantMonitor instead.  (Rarely should reentrancy be needed.)
michael@0:  *
michael@0:  * Instead of directly calling Monitor methods, it's safer and simpler
michael@0:  * to instead use the RAII wrappers MonitorAutoLock and
michael@0:  * MonitorAutoUnlock.
michael@0:  */
michael@0: class NS_COM_GLUE Monitor
michael@0: {
michael@0: public:
michael@0:     Monitor(const char* aName) :
michael@0:         mMutex(aName),
michael@0:         mCondVar(mMutex, "[Monitor.mCondVar]")
michael@0:     {}
michael@0: 
michael@0:     ~Monitor() {}
michael@0: 
michael@0:     void Lock()
michael@0:     {
michael@0:         mMutex.Lock();
michael@0:     }
michael@0: 
michael@0:     void Unlock()
michael@0:     {
michael@0:         mMutex.Unlock();
michael@0:     }
michael@0: 
michael@0:     nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)
michael@0:     {
michael@0:         return mCondVar.Wait(interval);
michael@0:     }
michael@0: 
michael@0:     nsresult Notify()
michael@0:     {
michael@0:         return mCondVar.Notify();
michael@0:     }
michael@0: 
michael@0:     nsresult NotifyAll()
michael@0:     {
michael@0:         return mCondVar.NotifyAll();
michael@0:     }
michael@0: 
michael@0:     void AssertCurrentThreadOwns() const
michael@0:     {
michael@0:         mMutex.AssertCurrentThreadOwns();
michael@0:     }
michael@0: 
michael@0:     void AssertNotCurrentThreadOwns() const
michael@0:     {
michael@0:         mMutex.AssertNotCurrentThreadOwns();
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     Monitor();
michael@0:     Monitor(const Monitor&);
michael@0:     Monitor& operator =(const Monitor&);
michael@0: 
michael@0:     Mutex mMutex;
michael@0:     CondVar mCondVar;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Lock the monitor for the lexical scope instances of this class are
michael@0:  * bound to (except for MonitorAutoUnlock in nested scopes).
michael@0:  *
michael@0:  * The monitor must be unlocked when instances of this class are
michael@0:  * created.
michael@0:  */
michael@0: class NS_COM_GLUE MOZ_STACK_CLASS MonitorAutoLock
michael@0: {
michael@0: public:
michael@0:     MonitorAutoLock(Monitor& aMonitor) :
michael@0:         mMonitor(&aMonitor)
michael@0:     {
michael@0:         mMonitor->Lock();
michael@0:     }
michael@0:     
michael@0:     ~MonitorAutoLock()
michael@0:     {
michael@0:         mMonitor->Unlock();
michael@0:     }
michael@0:  
michael@0:     nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)
michael@0:     {
michael@0:        return mMonitor->Wait(interval);
michael@0:     }
michael@0: 
michael@0:     nsresult Notify()
michael@0:     {
michael@0:         return mMonitor->Notify();
michael@0:     }
michael@0: 
michael@0:     nsresult NotifyAll()
michael@0:     {
michael@0:         return mMonitor->NotifyAll();
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     MonitorAutoLock();
michael@0:     MonitorAutoLock(const MonitorAutoLock&);
michael@0:     MonitorAutoLock& operator =(const MonitorAutoLock&);
michael@0:     static void* operator new(size_t) CPP_THROW_NEW;
michael@0:     static void operator delete(void*);
michael@0: 
michael@0:     Monitor* mMonitor;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Unlock the monitor for the lexical scope instances of this class
michael@0:  * are bound to (except for MonitorAutoLock in nested scopes).
michael@0:  *
michael@0:  * The monitor must be locked by the current thread when instances of
michael@0:  * this class are created.
michael@0:  */
michael@0: class NS_COM_GLUE MOZ_STACK_CLASS MonitorAutoUnlock
michael@0: {
michael@0: public:
michael@0:     MonitorAutoUnlock(Monitor& aMonitor) :
michael@0:         mMonitor(&aMonitor)
michael@0:     {
michael@0:         mMonitor->Unlock();
michael@0:     }
michael@0:     
michael@0:     ~MonitorAutoUnlock()
michael@0:     {
michael@0:         mMonitor->Lock();
michael@0:     }
michael@0:  
michael@0: private:
michael@0:     MonitorAutoUnlock();
michael@0:     MonitorAutoUnlock(const MonitorAutoUnlock&);
michael@0:     MonitorAutoUnlock& operator =(const MonitorAutoUnlock&);
michael@0:     static void* operator new(size_t) CPP_THROW_NEW;
michael@0:     static void operator delete(void*);
michael@0: 
michael@0:     Monitor* mMonitor;
michael@0: };
michael@0: 
michael@0: } // namespace mozilla
michael@0: 
michael@0: #endif // mozilla_Monitor_h