1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/xpcom/threads/nsThread.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,192 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef nsThread_h__
1.11 +#define nsThread_h__
1.12 +
1.13 +#include "mozilla/Mutex.h"
1.14 +#include "nsIThreadInternal.h"
1.15 +#include "nsISupportsPriority.h"
1.16 +#include "nsEventQueue.h"
1.17 +#include "nsThreadUtils.h"
1.18 +#include "nsString.h"
1.19 +#include "nsTObserverArray.h"
1.20 +#include "mozilla/Attributes.h"
1.21 +#include "nsAutoPtr.h"
1.22 +
1.23 +// A native thread
1.24 +class nsThread : public nsIThreadInternal,
1.25 + public nsISupportsPriority
1.26 +{
1.27 +public:
1.28 + NS_DECL_THREADSAFE_ISUPPORTS
1.29 + NS_DECL_NSIEVENTTARGET
1.30 + NS_DECL_NSITHREAD
1.31 + NS_DECL_NSITHREADINTERNAL
1.32 + NS_DECL_NSISUPPORTSPRIORITY
1.33 +
1.34 + enum MainThreadFlag {
1.35 + MAIN_THREAD,
1.36 + NOT_MAIN_THREAD
1.37 + };
1.38 +
1.39 + nsThread(MainThreadFlag aMainThread, uint32_t aStackSize);
1.40 +
1.41 + // Initialize this as a wrapper for a new PRThread.
1.42 + nsresult Init();
1.43 +
1.44 + // Initialize this as a wrapper for the current PRThread.
1.45 + nsresult InitCurrentThread();
1.46 +
1.47 + // The PRThread corresponding to this thread.
1.48 + PRThread *GetPRThread() { return mThread; }
1.49 +
1.50 + // If this flag is true, then the nsThread was created using
1.51 + // nsIThreadManager::NewThread.
1.52 + bool ShutdownRequired() { return mShutdownRequired; }
1.53 +
1.54 + // Clear the observer list.
1.55 + void ClearObservers() { mEventObservers.Clear(); }
1.56 +
1.57 + static nsresult
1.58 + SetMainThreadObserver(nsIThreadObserver* aObserver);
1.59 +
1.60 +protected:
1.61 + static nsIThreadObserver* sMainThreadObserver;
1.62 +
1.63 + class nsChainedEventQueue;
1.64 +
1.65 + class nsNestedEventTarget;
1.66 + friend class nsNestedEventTarget;
1.67 +
1.68 + friend class nsThreadShutdownEvent;
1.69 +
1.70 + virtual ~nsThread();
1.71 +
1.72 + bool ShuttingDown() { return mShutdownContext != nullptr; }
1.73 +
1.74 + static void ThreadFunc(void *arg);
1.75 +
1.76 + // Helper
1.77 + already_AddRefed<nsIThreadObserver> GetObserver() {
1.78 + nsIThreadObserver *obs;
1.79 + nsThread::GetObserver(&obs);
1.80 + return already_AddRefed<nsIThreadObserver>(obs);
1.81 + }
1.82 +
1.83 + // Wrappers for event queue methods:
1.84 + bool GetEvent(bool mayWait, nsIRunnable **event) {
1.85 + return mEvents->GetEvent(mayWait, event);
1.86 + }
1.87 + nsresult PutEvent(nsIRunnable *event, nsNestedEventTarget *target);
1.88 +
1.89 + nsresult DispatchInternal(nsIRunnable *event, uint32_t flags,
1.90 + nsNestedEventTarget *target);
1.91 +
1.92 + // Wrapper for nsEventQueue that supports chaining.
1.93 + class nsChainedEventQueue {
1.94 + public:
1.95 + nsChainedEventQueue()
1.96 + : mNext(nullptr) {
1.97 + }
1.98 +
1.99 + bool GetEvent(bool mayWait, nsIRunnable **event) {
1.100 + return mQueue.GetEvent(mayWait, event);
1.101 + }
1.102 +
1.103 + bool PutEvent(nsIRunnable *event) {
1.104 + return mQueue.PutEvent(event);
1.105 + }
1.106 +
1.107 + bool HasPendingEvent() {
1.108 + return mQueue.HasPendingEvent();
1.109 + }
1.110 +
1.111 + nsChainedEventQueue *mNext;
1.112 + nsRefPtr<nsNestedEventTarget> mEventTarget;
1.113 +
1.114 + private:
1.115 + nsEventQueue mQueue;
1.116 + };
1.117 +
1.118 + class nsNestedEventTarget MOZ_FINAL : public nsIEventTarget {
1.119 + public:
1.120 + NS_DECL_THREADSAFE_ISUPPORTS
1.121 + NS_DECL_NSIEVENTTARGET
1.122 +
1.123 + nsNestedEventTarget(nsThread *thread, nsChainedEventQueue *queue)
1.124 + : mThread(thread), mQueue(queue) {
1.125 + }
1.126 +
1.127 + nsRefPtr<nsThread> mThread;
1.128 +
1.129 + // This is protected by mThread->mLock.
1.130 + nsChainedEventQueue* mQueue;
1.131 +
1.132 + private:
1.133 + ~nsNestedEventTarget() {}
1.134 + };
1.135 +
1.136 + // This lock protects access to mObserver, mEvents and mEventsAreDoomed.
1.137 + // All of those fields are only modified on the thread itself (never from
1.138 + // another thread). This means that we can avoid holding the lock while
1.139 + // using mObserver and mEvents on the thread itself. When calling PutEvent
1.140 + // on mEvents, we have to hold the lock to synchronize with PopEventQueue.
1.141 + mozilla::Mutex mLock;
1.142 +
1.143 + nsCOMPtr<nsIThreadObserver> mObserver;
1.144 +
1.145 + // Only accessed on the target thread.
1.146 + nsAutoTObserverArray<nsCOMPtr<nsIThreadObserver>, 2> mEventObservers;
1.147 +
1.148 + nsChainedEventQueue *mEvents; // never null
1.149 + nsChainedEventQueue mEventsRoot;
1.150 +
1.151 + int32_t mPriority;
1.152 + PRThread *mThread;
1.153 + uint32_t mRunningEvent; // counter
1.154 + uint32_t mStackSize;
1.155 +
1.156 + struct nsThreadShutdownContext *mShutdownContext;
1.157 +
1.158 + bool mShutdownRequired;
1.159 + // Set to true when events posted to this thread will never run.
1.160 + bool mEventsAreDoomed;
1.161 + MainThreadFlag mIsMainThread;
1.162 +};
1.163 +
1.164 +//-----------------------------------------------------------------------------
1.165 +
1.166 +class nsThreadSyncDispatch : public nsRunnable {
1.167 +public:
1.168 + nsThreadSyncDispatch(nsIThread *origin, nsIRunnable *task)
1.169 + : mOrigin(origin), mSyncTask(task), mResult(NS_ERROR_NOT_INITIALIZED) {
1.170 + }
1.171 +
1.172 + bool IsPending() {
1.173 + return mSyncTask != nullptr;
1.174 + }
1.175 +
1.176 + nsresult Result() {
1.177 + return mResult;
1.178 + }
1.179 +
1.180 +private:
1.181 + NS_DECL_NSIRUNNABLE
1.182 +
1.183 + nsCOMPtr<nsIThread> mOrigin;
1.184 + nsCOMPtr<nsIRunnable> mSyncTask;
1.185 + nsresult mResult;
1.186 +};
1.187 +
1.188 +#if defined(XP_UNIX) && !defined(ANDROID) && !defined(DEBUG) && HAVE_UALARM \
1.189 + && defined(_GNU_SOURCE)
1.190 +# define MOZ_CANARY
1.191 +
1.192 +extern int sCanaryOutputFD;
1.193 +#endif
1.194 +
1.195 +#endif // nsThread_h__
