1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/glue/Monitor.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,158 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
1.5 + * vim: sw=2 ts=8 et :
1.6 + */
1.7 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.8 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.9 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.10 +
1.11 +#ifndef mozilla_Monitor_h
1.12 +#define mozilla_Monitor_h
1.13 +
1.14 +#include "mozilla/CondVar.h"
1.15 +#include "mozilla/Mutex.h"
1.16 +
1.17 +namespace mozilla {
1.18 +
1.19 +/**
1.20 + * Monitor provides a *non*-reentrant monitor: *not* a Java-style
1.21 + * monitor. If your code needs support for reentrancy, use
1.22 + * ReentrantMonitor instead. (Rarely should reentrancy be needed.)
1.23 + *
1.24 + * Instead of directly calling Monitor methods, it's safer and simpler
1.25 + * to instead use the RAII wrappers MonitorAutoLock and
1.26 + * MonitorAutoUnlock.
1.27 + */
1.28 +class NS_COM_GLUE Monitor
1.29 +{
1.30 +public:
1.31 + Monitor(const char* aName) :
1.32 + mMutex(aName),
1.33 + mCondVar(mMutex, "[Monitor.mCondVar]")
1.34 + {}
1.35 +
1.36 + ~Monitor() {}
1.37 +
1.38 + void Lock()
1.39 + {
1.40 + mMutex.Lock();
1.41 + }
1.42 +
1.43 + void Unlock()
1.44 + {
1.45 + mMutex.Unlock();
1.46 + }
1.47 +
1.48 + nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)
1.49 + {
1.50 + return mCondVar.Wait(interval);
1.51 + }
1.52 +
1.53 + nsresult Notify()
1.54 + {
1.55 + return mCondVar.Notify();
1.56 + }
1.57 +
1.58 + nsresult NotifyAll()
1.59 + {
1.60 + return mCondVar.NotifyAll();
1.61 + }
1.62 +
1.63 + void AssertCurrentThreadOwns() const
1.64 + {
1.65 + mMutex.AssertCurrentThreadOwns();
1.66 + }
1.67 +
1.68 + void AssertNotCurrentThreadOwns() const
1.69 + {
1.70 + mMutex.AssertNotCurrentThreadOwns();
1.71 + }
1.72 +
1.73 +private:
1.74 + Monitor();
1.75 + Monitor(const Monitor&);
1.76 + Monitor& operator =(const Monitor&);
1.77 +
1.78 + Mutex mMutex;
1.79 + CondVar mCondVar;
1.80 +};
1.81 +
1.82 +/**
1.83 + * Lock the monitor for the lexical scope instances of this class are
1.84 + * bound to (except for MonitorAutoUnlock in nested scopes).
1.85 + *
1.86 + * The monitor must be unlocked when instances of this class are
1.87 + * created.
1.88 + */
1.89 +class NS_COM_GLUE MOZ_STACK_CLASS MonitorAutoLock
1.90 +{
1.91 +public:
1.92 + MonitorAutoLock(Monitor& aMonitor) :
1.93 + mMonitor(&aMonitor)
1.94 + {
1.95 + mMonitor->Lock();
1.96 + }
1.97 +
1.98 + ~MonitorAutoLock()
1.99 + {
1.100 + mMonitor->Unlock();
1.101 + }
1.102 +
1.103 + nsresult Wait(PRIntervalTime interval = PR_INTERVAL_NO_TIMEOUT)
1.104 + {
1.105 + return mMonitor->Wait(interval);
1.106 + }
1.107 +
1.108 + nsresult Notify()
1.109 + {
1.110 + return mMonitor->Notify();
1.111 + }
1.112 +
1.113 + nsresult NotifyAll()
1.114 + {
1.115 + return mMonitor->NotifyAll();
1.116 + }
1.117 +
1.118 +private:
1.119 + MonitorAutoLock();
1.120 + MonitorAutoLock(const MonitorAutoLock&);
1.121 + MonitorAutoLock& operator =(const MonitorAutoLock&);
1.122 + static void* operator new(size_t) CPP_THROW_NEW;
1.123 + static void operator delete(void*);
1.124 +
1.125 + Monitor* mMonitor;
1.126 +};
1.127 +
1.128 +/**
1.129 + * Unlock the monitor for the lexical scope instances of this class
1.130 + * are bound to (except for MonitorAutoLock in nested scopes).
1.131 + *
1.132 + * The monitor must be locked by the current thread when instances of
1.133 + * this class are created.
1.134 + */
1.135 +class NS_COM_GLUE MOZ_STACK_CLASS MonitorAutoUnlock
1.136 +{
1.137 +public:
1.138 + MonitorAutoUnlock(Monitor& aMonitor) :
1.139 + mMonitor(&aMonitor)
1.140 + {
1.141 + mMonitor->Unlock();
1.142 + }
1.143 +
1.144 + ~MonitorAutoUnlock()
1.145 + {
1.146 + mMonitor->Lock();
1.147 + }
1.148 +
1.149 +private:
1.150 + MonitorAutoUnlock();
1.151 + MonitorAutoUnlock(const MonitorAutoUnlock&);
1.152 + MonitorAutoUnlock& operator =(const MonitorAutoUnlock&);
1.153 + static void* operator new(size_t) CPP_THROW_NEW;
1.154 + static void operator delete(void*);
1.155 +
1.156 + Monitor* mMonitor;
1.157 +};
1.158 +
1.159 +} // namespace mozilla
1.160 +
1.161 +#endif // mozilla_Monitor_h
