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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 ipc_glue_MessageChannel_h
+#define ipc_glue_MessageChannel_h 1
+
+#include "base/basictypes.h"
+#include "base/message_loop.h"
+
+#include "mozilla/Function.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Monitor.h"
+#include "mozilla/Vector.h"
+#if defined(OS_WIN)
+#include "mozilla/ipc/Neutering.h"
+#endif // defined(OS_WIN)
+#include "mozilla/ipc/Transport.h"
+#if defined(MOZ_CRASHREPORTER) && defined(OS_WIN)
+#include "mozilla/mozalloc_oom.h"
+#include "nsExceptionHandler.h"
+#endif
+#include "MessageLink.h"
+
+#include <deque>
+#include <stack>
+#include <math.h>
+
+namespace mozilla {
+namespace ipc {
+
+class MessageChannel;
+class IToplevelProtocol;
+
+class RefCountedMonitor : public Monitor
+{
+ public:
+ RefCountedMonitor()
+ : Monitor("mozilla.ipc.MessageChannel.mMonitor")
+ {}
+
+ NS_INLINE_DECL_THREADSAFE_REFCOUNTING(RefCountedMonitor)
+
+ private:
+ ~RefCountedMonitor() {}
+};
+
+enum class SyncSendError {
+ SendSuccess,
+ PreviousTimeout,
+ SendingCPOWWhileDispatchingSync,
+ SendingCPOWWhileDispatchingUrgent,
+ NotConnectedBeforeSend,
+ DisconnectedDuringSend,
+ CancelledBeforeSend,
+ CancelledAfterSend,
+ TimedOut,
+ ReplyError,
+};
+
+enum ChannelState {
+ ChannelClosed,
+ ChannelOpening,
+ ChannelConnected,
+ ChannelTimeout,
+ ChannelClosing,
+ ChannelError
+};
+
+class AutoEnterTransaction;
+
+class MessageChannel : HasResultCodes
+{
+ friend class ProcessLink;
+ friend class ThreadLink;
+
+ class CxxStackFrame;
+ class InterruptFrame;
+
+ typedef mozilla::Monitor Monitor;
+
+ public:
+ static const int32_t kNoTimeout;
+
+ typedef IPC::Message Message;
+ typedef IPC::MessageInfo MessageInfo;
+ typedef mozilla::ipc::Transport Transport;
+
+ explicit MessageChannel(IToplevelProtocol *aListener);
+ ~MessageChannel();
+
+ // "Open" from the perspective of the transport layer; the underlying
+ // socketpair/pipe should already be created.
+ //
+ // Returns true if the transport layer was successfully connected,
+ // i.e., mChannelState == ChannelConnected.
+ bool Open(Transport* aTransport, MessageLoop* aIOLoop=0, Side aSide=UnknownSide);
+
+ // "Open" a connection to another thread in the same process.
+ //
+ // Returns true if the transport layer was successfully connected,
+ // i.e., mChannelState == ChannelConnected.
+ //
+ // For more details on the process of opening a channel between
+ // threads, see the extended comment on this function
+ // in MessageChannel.cpp.
+ bool Open(MessageChannel *aTargetChan, MessageLoop *aTargetLoop, Side aSide);
+
+ // Close the underlying transport channel.
+ void Close();
+
+ // Force the channel to behave as if a channel error occurred. Valid
+ // for process links only, not thread links.
+ void CloseWithError();
+
+ void CloseWithTimeout();
+
+ void SetAbortOnError(bool abort)
+ {
+ mAbortOnError = abort;
+ }
+
+ // Call aInvoke for each pending message until it returns false.
+ // XXX: You must get permission from an IPC peer to use this function
+ // since it requires custom deserialization and re-orders events.
+ void PeekMessages(mozilla::function<bool(const Message& aMsg)> aInvoke);
+
+ // Misc. behavioral traits consumers can request for this channel
+ enum ChannelFlags {
+ REQUIRE_DEFAULT = 0,
+ // Windows: if this channel operates on the UI thread, indicates
+ // WindowsMessageLoop code should enable deferred native message
+ // handling to prevent deadlocks. Should only be used for protocols
+ // that manage child processes which might create native UI, like
+ // plugins.
+ REQUIRE_DEFERRED_MESSAGE_PROTECTION = 1 << 0,
+ // Windows: When this flag is specified, any wait that occurs during
+ // synchronous IPC will be alertable, thus allowing a11y code in the
+ // chrome process to reenter content while content is waiting on a
+ // synchronous call.
+ REQUIRE_A11Y_REENTRY = 1 << 1,
+ };
+ void SetChannelFlags(ChannelFlags aFlags) { mFlags = aFlags; }
+ ChannelFlags GetChannelFlags() { return mFlags; }
+
+ // Asynchronously send a message to the other side of the channel
+ bool Send(Message* aMsg);
+
+ // Asynchronously deliver a message back to this side of the
+ // channel
+ bool Echo(Message* aMsg);
+
+ // Synchronously send |msg| (i.e., wait for |reply|)
+ bool Send(Message* aMsg, Message* aReply);
+
+ // Make an Interrupt call to the other side of the channel
+ bool Call(Message* aMsg, Message* aReply);
+
+ // Wait until a message is received
+ bool WaitForIncomingMessage();
+
+ bool CanSend() const;
+
+ // If sending a sync message returns an error, this function gives a more
+ // descriptive error message.
+ SyncSendError LastSendError() const {
+ AssertWorkerThread();
+ return mLastSendError;
+ }
+
+ // Currently only for debugging purposes, doesn't aquire mMonitor.
+ ChannelState GetChannelState__TotallyRacy() const {
+ return mChannelState;
+ }
+
+ void SetReplyTimeoutMs(int32_t aTimeoutMs);
+
+ bool IsOnCxxStack() const {
+ return !mCxxStackFrames.empty();
+ }
+
+ bool IsInTransaction() const;
+ void CancelCurrentTransaction();
+
+ /**
+ * This function is used by hang annotation code to determine which IPDL
+ * actor is highest in the call stack at the time of the hang. It should
+ * be called from the main thread when a sync or intr message is about to
+ * be sent.
+ */
+ int32_t GetTopmostMessageRoutingId() const;
+
+ // Unsound_IsClosed and Unsound_NumQueuedMessages are safe to call from any
+ // thread, but they make no guarantees about whether you'll get an
+ // up-to-date value; the values are written on one thread and read without
+ // locking, on potentially different threads. Thus you should only use
+ // them when you don't particularly care about getting a recent value (e.g.
+ // in a memory report).
+ bool Unsound_IsClosed() const {
+ return mLink ? mLink->Unsound_IsClosed() : true;
+ }
+ uint32_t Unsound_NumQueuedMessages() const {
+ return mLink ? mLink->Unsound_NumQueuedMessages() : 0;
+ }
+
+ static bool IsPumpingMessages() {
+ return sIsPumpingMessages;
+ }
+ static void SetIsPumpingMessages(bool aIsPumping) {
+ sIsPumpingMessages = aIsPumping;
+ }
+
+#ifdef OS_WIN
+ struct MOZ_STACK_CLASS SyncStackFrame
+ {
+ SyncStackFrame(MessageChannel* channel, bool interrupt);
+ ~SyncStackFrame();
+
+ bool mInterrupt;
+ bool mSpinNestedEvents;
+ bool mListenerNotified;
+ MessageChannel* mChannel;
+
+ // The previous stack frame for this channel.
+ SyncStackFrame* mPrev;
+
+ // The previous stack frame on any channel.
+ SyncStackFrame* mStaticPrev;
+ };
+ friend struct MessageChannel::SyncStackFrame;
+
+ static bool IsSpinLoopActive() {
+ for (SyncStackFrame* frame = sStaticTopFrame; frame; frame = frame->mPrev) {
+ if (frame->mSpinNestedEvents)
+ return true;
+ }
+ return false;
+ }
+
+ protected:
+ // The deepest sync stack frame for this channel.
+ SyncStackFrame* mTopFrame;
+
+ bool mIsSyncWaitingOnNonMainThread;
+
+ // The deepest sync stack frame on any channel.
+ static SyncStackFrame* sStaticTopFrame;
+
+ public:
+ void ProcessNativeEventsInInterruptCall();
+ static void NotifyGeckoEventDispatch();
+
+ private:
+ void SpinInternalEventLoop();
+#if defined(ACCESSIBILITY)
+ bool WaitForSyncNotifyWithA11yReentry();
+#endif // defined(ACCESSIBILITY)
+#endif // defined(OS_WIN)
+
+ private:
+ void CommonThreadOpenInit(MessageChannel *aTargetChan, Side aSide);
+ void OnOpenAsSlave(MessageChannel *aTargetChan, Side aSide);
+
+ void PostErrorNotifyTask();
+ void OnNotifyMaybeChannelError();
+ void ReportConnectionError(const char* aChannelName, Message* aMsg = nullptr) const;
+ void ReportMessageRouteError(const char* channelName) const;
+ bool MaybeHandleError(Result code, const Message& aMsg, const char* channelName);
+
+ void Clear();
+
+ // Send OnChannelConnected notification to listeners.
+ void DispatchOnChannelConnected();
+
+ bool InterruptEventOccurred();
+ bool HasPendingEvents();
+
+ void ProcessPendingRequests(AutoEnterTransaction& aTransaction);
+ bool ProcessPendingRequest(Message &&aUrgent);
+
+ void MaybeUndeferIncall();
+ void EnqueuePendingMessages();
+
+ // Dispatches an incoming message to its appropriate handler.
+ void DispatchMessage(Message &&aMsg);
+
+ // DispatchMessage will route to one of these functions depending on the
+ // protocol type of the message.
+ void DispatchSyncMessage(const Message &aMsg, Message*& aReply);
+ void DispatchUrgentMessage(const Message &aMsg);
+ void DispatchAsyncMessage(const Message &aMsg);
+ void DispatchRPCMessage(const Message &aMsg);
+ void DispatchInterruptMessage(Message &&aMsg, size_t aStackDepth);
+
+ // Return true if the wait ended because a notification was received.
+ //
+ // Return false if the time elapsed from when we started the process of
+ // waiting until afterwards exceeded the currently allotted timeout.
+ // That *DOES NOT* mean false => "no event" (== timeout); there are many
+ // circumstances that could cause the measured elapsed time to exceed the
+ // timeout EVEN WHEN we were notified.
+ //
+ // So in sum: true is a meaningful return value; false isn't,
+ // necessarily.
+ bool WaitForSyncNotify(bool aHandleWindowsMessages);
+ bool WaitForInterruptNotify();
+
+ bool WaitResponse(bool aWaitTimedOut);
+
+ bool ShouldContinueFromTimeout();
+
+ void EndTimeout();
+ void CancelTransaction(int transaction);
+
+ void RepostAllMessages();
+
+ // The "remote view of stack depth" can be different than the
+ // actual stack depth when there are out-of-turn replies. When we
+ // receive one, our actual Interrupt stack depth doesn't decrease, but
+ // the other side (that sent the reply) thinks it has. So, the
+ // "view" returned here is |stackDepth| minus the number of
+ // out-of-turn replies.
+ //
+ // Only called from the worker thread.
+ size_t RemoteViewOfStackDepth(size_t stackDepth) const {
+ AssertWorkerThread();
+ return stackDepth - mOutOfTurnReplies.size();
+ }
+
+ int32_t NextSeqno() {
+ AssertWorkerThread();
+ return (mSide == ChildSide) ? --mNextSeqno : ++mNextSeqno;
+ }
+
+ // This helper class manages mCxxStackDepth on behalf of MessageChannel.
+ // When the stack depth is incremented from zero to non-zero, it invokes
+ // a callback, and similarly for when the depth goes from non-zero to zero.
+ void EnteredCxxStack();
+ void ExitedCxxStack();
+
+ void EnteredCall();
+ void ExitedCall();
+
+ void EnteredSyncSend();
+ void ExitedSyncSend();
+
+ IToplevelProtocol *Listener() const {
+ return mListener;
+ }
+
+ void DebugAbort(const char* file, int line, const char* cond,
+ const char* why,
+ bool reply=false);
+
+ // This method is only safe to call on the worker thread, or in a
+ // debugger with all threads paused.
+ void DumpInterruptStack(const char* const pfx="") const;
+
+ private:
+ // Called from both threads
+ size_t InterruptStackDepth() const {
+ mMonitor->AssertCurrentThreadOwns();
+ return mInterruptStack.size();
+ }
+
+ bool AwaitingInterruptReply() const {
+ mMonitor->AssertCurrentThreadOwns();
+ return !mInterruptStack.empty();
+ }
+ bool AwaitingIncomingMessage() const {
+ mMonitor->AssertCurrentThreadOwns();
+ return mIsWaitingForIncoming;
+ }
+
+ class MOZ_STACK_CLASS AutoEnterWaitForIncoming
+ {
+ public:
+ explicit AutoEnterWaitForIncoming(MessageChannel& aChannel)
+ : mChannel(aChannel)
+ {
+ aChannel.mMonitor->AssertCurrentThreadOwns();
+ aChannel.mIsWaitingForIncoming = true;
+ }
+
+ ~AutoEnterWaitForIncoming()
+ {
+ mChannel.mIsWaitingForIncoming = false;
+ }
+
+ private:
+ MessageChannel& mChannel;
+ };
+ friend class AutoEnterWaitForIncoming;
+
+ // Returns true if we're dispatching an async message's callback.
+ bool DispatchingAsyncMessage() const {
+ AssertWorkerThread();
+ return mDispatchingAsyncMessage;
+ }
+
+ int DispatchingAsyncMessageNestedLevel() const {
+ AssertWorkerThread();
+ return mDispatchingAsyncMessageNestedLevel;
+ }
+
+ bool Connected() const;
+
+ private:
+ // Executed on the IO thread.
+ void NotifyWorkerThread();
+
+ // Return true if |aMsg| is a special message targeted at the IO
+ // thread, in which case it shouldn't be delivered to the worker.
+ bool MaybeInterceptSpecialIOMessage(const Message& aMsg);
+
+ void OnChannelConnected(int32_t peer_id);
+
+ // Tell the IO thread to close the channel and wait for it to ACK.
+ void SynchronouslyClose();
+
+ bool WasTransactionCanceled(int transaction);
+ bool ShouldDeferMessage(const Message& aMsg);
+ bool ShouldDeferInterruptMessage(const Message& aMsg, size_t aStackDepth);
+ void OnMessageReceivedFromLink(Message&& aMsg);
+ void OnChannelErrorFromLink();
+
+ private:
+ // Run on the not current thread.
+ void NotifyChannelClosed();
+ void NotifyMaybeChannelError();
+
+ private:
+ // Can be run on either thread
+ void AssertWorkerThread() const
+ {
+ MOZ_RELEASE_ASSERT(mWorkerLoopID == MessageLoop::current()->id(),
+ "not on worker thread!");
+ }
+
+ // The "link" thread is either the I/O thread (ProcessLink) or the
+ // other actor's work thread (ThreadLink). In either case, it is
+ // NOT our worker thread.
+ void AssertLinkThread() const
+ {
+ MOZ_RELEASE_ASSERT(mWorkerLoopID != MessageLoop::current()->id(),
+ "on worker thread but should not be!");
+ }
+
+ private:
+ class MessageTask :
+ public CancelableRunnable,
+ public LinkedListElement<RefPtr<MessageTask>>,
+ public nsIRunnablePriority
+ {
+ public:
+ explicit MessageTask(MessageChannel* aChannel, Message&& aMessage)
+ : mChannel(aChannel), mMessage(Move(aMessage)), mScheduled(false)
+ {}
+
+ NS_DECL_ISUPPORTS_INHERITED
+
+ NS_IMETHOD Run() override;
+ nsresult Cancel() override;
+ NS_IMETHOD GetPriority(uint32_t* aPriority) override;
+ void Post();
+ void Clear();
+
+ bool IsScheduled() const { return mScheduled; }
+
+ Message& Msg() { return mMessage; }
+ const Message& Msg() const { return mMessage; }
+
+ private:
+ MessageTask() = delete;
+ MessageTask(const MessageTask&) = delete;
+ ~MessageTask() {}
+
+ MessageChannel* mChannel;
+ Message mMessage;
+ bool mScheduled : 1;
+ };
+
+ bool ShouldRunMessage(const Message& aMsg);
+ void RunMessage(MessageTask& aTask);
+
+ typedef LinkedList<RefPtr<MessageTask>> MessageQueue;
+ typedef std::map<size_t, Message> MessageMap;
+ typedef IPC::Message::msgid_t msgid_t;
+
+ private:
+ // Based on presumption the listener owns and overlives the channel,
+ // this is never nullified.
+ IToplevelProtocol* mListener;
+ ChannelState mChannelState;
+ RefPtr<RefCountedMonitor> mMonitor;
+ Side mSide;
+ MessageLink* mLink;
+ MessageLoop* mWorkerLoop; // thread where work is done
+ RefPtr<CancelableRunnable> mChannelErrorTask; // NotifyMaybeChannelError runnable
+
+ // id() of mWorkerLoop. This persists even after mWorkerLoop is cleared
+ // during channel shutdown.
+ int mWorkerLoopID;
+
+ // Timeout periods are broken up in two to prevent system suspension from
+ // triggering an abort. This method (called by WaitForEvent with a 'did
+ // timeout' flag) decides if we should wait again for half of mTimeoutMs
+ // or give up.
+ int32_t mTimeoutMs;
+ bool mInTimeoutSecondHalf;
+
+ // Worker-thread only; sequence numbers for messages that require
+ // synchronous replies.
+ int32_t mNextSeqno;
+
+ static bool sIsPumpingMessages;
+
+ // If ::Send returns false, this gives a more descriptive error.
+ SyncSendError mLastSendError;
+
+ template<class T>
+ class AutoSetValue {
+ public:
+ explicit AutoSetValue(T &var, const T &newValue)
+ : mVar(var), mPrev(var), mNew(newValue)
+ {
+ mVar = newValue;
+ }
+ ~AutoSetValue() {
+ // The value may have been zeroed if the transaction was
+ // canceled. In that case we shouldn't return it to its previous
+ // value.
+ if (mVar == mNew) {
+ mVar = mPrev;
+ }
+ }
+ private:
+ T& mVar;
+ T mPrev;
+ T mNew;
+ };
+
+ bool mDispatchingAsyncMessage;
+ int mDispatchingAsyncMessageNestedLevel;
+
+ // When we send an urgent request from the parent process, we could race
+ // with an RPC message that was issued by the child beforehand. In this
+ // case, if the parent were to wake up while waiting for the urgent reply,
+ // and process the RPC, it could send an additional urgent message. The
+ // child would wake up to process the urgent message (as it always will),
+ // then send a reply, which could be received by the parent out-of-order
+ // with respect to the first urgent reply.
+ //
+ // To address this problem, urgent or RPC requests are associated with a
+ // "transaction". Whenever one side of the channel wishes to start a
+ // chain of RPC/urgent messages, it allocates a new transaction ID. Any
+ // messages the parent receives, not apart of this transaction, are
+ // deferred. When issuing RPC/urgent requests on top of a started
+ // transaction, the initiating transaction ID is used.
+ //
+ // To ensure IDs are unique, we use sequence numbers for transaction IDs,
+ // which grow in opposite directions from child to parent.
+
+ friend class AutoEnterTransaction;
+ AutoEnterTransaction *mTransactionStack;
+
+ int32_t CurrentNestedInsideSyncTransaction() const;
+
+ bool AwaitingSyncReply() const;
+ int AwaitingSyncReplyNestedLevel() const;
+
+ bool DispatchingSyncMessage() const;
+ int DispatchingSyncMessageNestedLevel() const;
+
+ // If a sync message times out, we store its sequence number here. Any
+ // future sync messages will fail immediately. Once the reply for original
+ // sync message is received, we allow sync messages again.
+ //
+ // When a message times out, nothing is done to inform the other side. The
+ // other side will eventually dispatch the message and send a reply. Our
+ // side is responsible for replying to all sync messages sent by the other
+ // side when it dispatches the timed out message. The response is always an
+ // error.
+ //
+ // A message is only timed out if it initiated a transaction. This avoids
+ // hitting a lot of corner cases with message nesting that we don't really
+ // care about.
+ int32_t mTimedOutMessageSeqno;
+ int mTimedOutMessageNestedLevel;
+
+ // Queue of all incoming messages.
+ //
+ // If both this side and the other side are functioning correctly, the queue
+ // can only be in certain configurations. Let
+ //
+ // |A<| be an async in-message,
+ // |S<| be a sync in-message,
+ // |C<| be an Interrupt in-call,
+ // |R<| be an Interrupt reply.
+ //
+ // The queue can only match this configuration
+ //
+ // A<* (S< | C< | R< (?{mInterruptStack.size() == 1} A<* (S< | C<)))
+ //
+ // The other side can send as many async messages |A<*| as it wants before
+ // sending us a blocking message.
+ //
+ // The first case is |S<|, a sync in-msg. The other side must be blocked,
+ // and thus can't send us any more messages until we process the sync
+ // in-msg.
+ //
+ // The second case is |C<|, an Interrupt in-call; the other side must be blocked.
+ // (There's a subtlety here: this in-call might have raced with an
+ // out-call, but we detect that with the mechanism below,
+ // |mRemoteStackDepth|, and races don't matter to the queue.)
+ //
+ // Final case, the other side replied to our most recent out-call |R<|.
+ // If that was the *only* out-call on our stack, |?{mInterruptStack.size() == 1}|,
+ // then other side "finished with us," and went back to its own business.
+ // That business might have included sending any number of async message
+ // |A<*| until sending a blocking message |(S< | C<)|. If we had more than
+ // one Interrupt call on our stack, the other side *better* not have sent us
+ // another blocking message, because it's blocked on a reply from us.
+ //
+ MessageQueue mPending;
+
+ // Stack of all the out-calls on which this channel is awaiting responses.
+ // Each stack refers to a different protocol and the stacks are mutually
+ // exclusive: multiple outcalls of the same kind cannot be initiated while
+ // another is active.
+ std::stack<MessageInfo> mInterruptStack;
+
+ // This is what we think the Interrupt stack depth is on the "other side" of this
+ // Interrupt channel. We maintain this variable so that we can detect racy Interrupt
+ // calls. With each Interrupt out-call sent, we send along what *we* think the
+ // stack depth of the remote side is *before* it will receive the Interrupt call.
+ //
+ // After sending the out-call, our stack depth is "incremented" by pushing
+ // that pending message onto mPending.
+ //
+ // Then when processing an in-call |c|, it must be true that
+ //
+ // mInterruptStack.size() == c.remoteDepth
+ //
+ // I.e., my depth is actually the same as what the other side thought it
+ // was when it sent in-call |c|. If this fails to hold, we have detected
+ // racy Interrupt calls.
+ //
+ // We then increment mRemoteStackDepth *just before* processing the
+ // in-call, since we know the other side is waiting on it, and decrement
+ // it *just after* finishing processing that in-call, since our response
+ // will pop the top of the other side's |mPending|.
+ //
+ // One nice aspect of this race detection is that it is symmetric; if one
+ // side detects a race, then the other side must also detect the same race.
+ size_t mRemoteStackDepthGuess;
+
+ // Approximation of code frames on the C++ stack. It can only be
+ // interpreted as the implication:
+ //
+ // !mCxxStackFrames.empty() => MessageChannel code on C++ stack
+ //
+ // This member is only accessed on the worker thread, and so is not
+ // protected by mMonitor. It is managed exclusively by the helper
+ // |class CxxStackFrame|.
+ mozilla::Vector<InterruptFrame> mCxxStackFrames;
+
+ // Did we process an Interrupt out-call during this stack? Only meaningful in
+ // ExitedCxxStack(), from which this variable is reset.
+ bool mSawInterruptOutMsg;
+
+ // Are we waiting on this channel for an incoming message? This is used
+ // to implement WaitForIncomingMessage(). Must only be accessed while owning
+ // mMonitor.
+ bool mIsWaitingForIncoming;
+
+ // Map of replies received "out of turn", because of Interrupt
+ // in-calls racing with replies to outstanding in-calls. See
+ // https://bugzilla.mozilla.org/show_bug.cgi?id=521929.
+ MessageMap mOutOfTurnReplies;
+
+ // Stack of Interrupt in-calls that were deferred because of race
+ // conditions.
+ std::stack<Message> mDeferred;
+
+#ifdef OS_WIN
+ HANDLE mEvent;
+#endif
+
+ // Should the channel abort the process from the I/O thread when
+ // a channel error occurs?
+ bool mAbortOnError;
+
+ // True if the listener has already been notified of a channel close or
+ // error.
+ bool mNotifiedChannelDone;
+
+ // See SetChannelFlags
+ ChannelFlags mFlags;
+
+ // Task and state used to asynchronously notify channel has been connected
+ // safely. This is necessary to be able to cancel notification if we are
+ // closed at the same time.
+ RefPtr<CancelableRunnable> mOnChannelConnectedTask;
+ bool mPeerPidSet;
+ int32_t mPeerPid;
+};
+
+void
+CancelCPOWs();
+
+} // namespace ipc
+} // namespace mozilla
+
+#endif // ifndef ipc_glue_MessageChannel_h