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gecko-dev/netwerk/base/nsInputStreamPump.cpp

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=4 sts=2 sw=2 et cin: */
/* 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/. */
#include "nsIOService.h"
#include "nsInputStreamPump.h"
#include "nsIStreamTransportService.h"
#include "nsISeekableStream.h"
#include "nsITransport.h"
#include "nsIThreadRetargetableStreamListener.h"
#include "nsThreadUtils.h"
#include "nsCOMPtr.h"
#include "mozilla/Logging.h"
#include "mozilla/NonBlockingAsyncInputStream.h"
#include "mozilla/SlicedInputStream.h"
#include "GeckoProfiler.h"
#include "nsIStreamListener.h"
#include "nsILoadGroup.h"
#include "nsNetCID.h"
#include "nsStreamUtils.h"
#include <algorithm>
static NS_DEFINE_CID(kStreamTransportServiceCID, NS_STREAMTRANSPORTSERVICE_CID);
//
// MOZ_LOG=nsStreamPump:5
//
static mozilla::LazyLogModule gStreamPumpLog("nsStreamPump");
#undef LOG
#define LOG(args) MOZ_LOG(gStreamPumpLog, mozilla::LogLevel::Debug, args)
//-----------------------------------------------------------------------------
// nsInputStreamPump methods
//-----------------------------------------------------------------------------
nsInputStreamPump::nsInputStreamPump()
: mState(STATE_IDLE),
mStreamOffset(0),
mStreamLength(0),
mSegSize(0),
mSegCount(0),
mStatus(NS_OK),
mSuspendCount(0),
mLoadFlags(LOAD_NORMAL),
mIsPending(false),
mProcessingCallbacks(false),
mWaitingForInputStreamReady(false),
mCloseWhenDone(false),
mRetargeting(false),
mAsyncStreamIsBuffered(false),
mMutex("nsInputStreamPump") {}
nsresult nsInputStreamPump::Create(nsInputStreamPump** result,
nsIInputStream* stream, uint32_t segsize,
uint32_t segcount, bool closeWhenDone,
nsIEventTarget* mainThreadTarget) {
nsresult rv = NS_ERROR_OUT_OF_MEMORY;
RefPtr<nsInputStreamPump> pump = new nsInputStreamPump();
if (pump) {
rv = pump->Init(stream, segsize, segcount, closeWhenDone, mainThreadTarget);
if (NS_SUCCEEDED(rv)) {
pump.forget(result);
}
}
return rv;
}
struct PeekData {
PeekData(nsInputStreamPump::PeekSegmentFun fun, void* closure)
: mFunc(fun), mClosure(closure) {}
nsInputStreamPump::PeekSegmentFun mFunc;
void* mClosure;
};
static nsresult CallPeekFunc(nsIInputStream* aInStream, void* aClosure,
const char* aFromSegment, uint32_t aToOffset,
uint32_t aCount, uint32_t* aWriteCount) {
NS_ASSERTION(aToOffset == 0, "Called more than once?");
NS_ASSERTION(aCount > 0, "Called without data?");
PeekData* data = static_cast<PeekData*>(aClosure);
data->mFunc(data->mClosure, reinterpret_cast<const uint8_t*>(aFromSegment),
aCount);
return NS_BINDING_ABORTED;
}
nsresult nsInputStreamPump::PeekStream(PeekSegmentFun callback, void* closure) {
RecursiveMutexAutoLock lock(mMutex);
MOZ_ASSERT(mAsyncStream, "PeekStream called without stream");
nsresult rv = CreateBufferedStreamIfNeeded();
NS_ENSURE_SUCCESS(rv, rv);
// See if the pipe is closed by checking the return of Available.
uint64_t dummy64;
rv = mAsyncStream->Available(&dummy64);
if (NS_FAILED(rv)) return rv;
uint32_t dummy = (uint32_t)std::min(dummy64, (uint64_t)UINT32_MAX);
PeekData data(callback, closure);
return mAsyncStream->ReadSegments(
CallPeekFunc, &data, net::nsIOService::gDefaultSegmentSize, &dummy);
}
nsresult nsInputStreamPump::EnsureWaiting() {
mMutex.AssertCurrentThreadIn();
// no need to worry about multiple threads... an input stream pump lives
// on only one thread at a time.
MOZ_ASSERT(mAsyncStream);
if (!mWaitingForInputStreamReady && !mProcessingCallbacks) {
// Ensure OnStateStop is called on the main thread.
if (mState == STATE_STOP) {
nsCOMPtr<nsIEventTarget> mainThread =
mLabeledMainThreadTarget ? mLabeledMainThreadTarget
: do_AddRef(GetMainThreadEventTarget());
if (mTargetThread != mainThread) {
mTargetThread = mainThread;
}
}
MOZ_ASSERT(mTargetThread);
nsresult rv = mAsyncStream->AsyncWait(this, 0, 0, mTargetThread);
if (NS_FAILED(rv)) {
NS_ERROR("AsyncWait failed");
return rv;
}
// Any retargeting during STATE_START or START_TRANSFER is complete
// after the call to AsyncWait; next callback wil be on mTargetThread.
mRetargeting = false;
mWaitingForInputStreamReady = true;
}
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsInputStreamPump::nsISupports
//-----------------------------------------------------------------------------
// although this class can only be accessed from one thread at a time, we do
// allow its ownership to move from thread to thread, assuming the consumer
// understands the limitations of this.
NS_IMPL_ISUPPORTS(nsInputStreamPump, nsIRequest, nsIThreadRetargetableRequest,
nsIInputStreamCallback, nsIInputStreamPump)
//-----------------------------------------------------------------------------
// nsInputStreamPump::nsIRequest
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsInputStreamPump::GetName(nsACString& result) {
RecursiveMutexAutoLock lock(mMutex);
result.Truncate();
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::IsPending(bool* result) {
RecursiveMutexAutoLock lock(mMutex);
*result = (mState != STATE_IDLE);
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::GetStatus(nsresult* status) {
RecursiveMutexAutoLock lock(mMutex);
*status = mStatus;
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::Cancel(nsresult status) {
MOZ_ASSERT(NS_IsMainThread());
RecursiveMutexAutoLock lock(mMutex);
LOG(("nsInputStreamPump::Cancel [this=%p status=%" PRIx32 "]\n", this,
static_cast<uint32_t>(status)));
if (NS_FAILED(mStatus)) {
LOG((" already canceled\n"));
return NS_OK;
}
NS_ASSERTION(NS_FAILED(status), "cancel with non-failure status code");
mStatus = status;
// close input stream
if (mAsyncStream) {
mAsyncStream->CloseWithStatus(status);
if (mSuspendCount == 0) EnsureWaiting();
// Otherwise, EnsureWaiting will be called by Resume().
// Note that while suspended, OnInputStreamReady will
// not do anything, and also note that calling asyncWait
// on a closed stream works and will dispatch an event immediately.
}
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::Suspend() {
RecursiveMutexAutoLock lock(mMutex);
LOG(("nsInputStreamPump::Suspend [this=%p]\n", this));
NS_ENSURE_TRUE(mState != STATE_IDLE, NS_ERROR_UNEXPECTED);
++mSuspendCount;
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::Resume() {
RecursiveMutexAutoLock lock(mMutex);
LOG(("nsInputStreamPump::Resume [this=%p]\n", this));
NS_ENSURE_TRUE(mSuspendCount > 0, NS_ERROR_UNEXPECTED);
NS_ENSURE_TRUE(mState != STATE_IDLE, NS_ERROR_UNEXPECTED);
// There is a brief in-between state when we null out mAsyncStream in
// OnStateStop() before calling OnStopRequest, and only afterwards set
// STATE_IDLE, which we need to handle gracefully.
if (--mSuspendCount == 0 && mAsyncStream) EnsureWaiting();
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::GetLoadFlags(nsLoadFlags* aLoadFlags) {
RecursiveMutexAutoLock lock(mMutex);
*aLoadFlags = mLoadFlags;
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::SetLoadFlags(nsLoadFlags aLoadFlags) {
RecursiveMutexAutoLock lock(mMutex);
mLoadFlags = aLoadFlags;
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::GetLoadGroup(nsILoadGroup** aLoadGroup) {
RecursiveMutexAutoLock lock(mMutex);
NS_IF_ADDREF(*aLoadGroup = mLoadGroup);
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::SetLoadGroup(nsILoadGroup* aLoadGroup) {
RecursiveMutexAutoLock lock(mMutex);
mLoadGroup = aLoadGroup;
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsInputStreamPump::nsIInputStreamPump implementation
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsInputStreamPump::Init(nsIInputStream* stream, uint32_t segsize,
uint32_t segcount, bool closeWhenDone,
nsIEventTarget* mainThreadTarget) {
NS_ENSURE_TRUE(mState == STATE_IDLE, NS_ERROR_IN_PROGRESS);
mStream = stream;
mSegSize = segsize;
mSegCount = segcount;
mCloseWhenDone = closeWhenDone;
mLabeledMainThreadTarget = mainThreadTarget;
return NS_OK;
}
NS_IMETHODIMP
nsInputStreamPump::AsyncRead(nsIStreamListener* listener, nsISupports* ctxt) {
RecursiveMutexAutoLock lock(mMutex);
NS_ENSURE_TRUE(mState == STATE_IDLE, NS_ERROR_IN_PROGRESS);
NS_ENSURE_ARG_POINTER(listener);
MOZ_ASSERT(NS_IsMainThread(),
"nsInputStreamPump should be read from the "
"main thread only.");
//
// OK, we need to use the stream transport service if
//
// (1) the stream is blocking
// (2) the stream does not support nsIAsyncInputStream
//
bool nonBlocking;
nsresult rv = mStream->IsNonBlocking(&nonBlocking);
if (NS_FAILED(rv)) return rv;
if (nonBlocking) {
mAsyncStream = do_QueryInterface(mStream);
if (!mAsyncStream) {
rv = NonBlockingAsyncInputStream::Create(mStream.forget(),
getter_AddRefs(mAsyncStream));
if (NS_WARN_IF(NS_FAILED(rv))) return rv;
}
MOZ_ASSERT(mAsyncStream);
}
if (!mAsyncStream) {
// ok, let's use the stream transport service to read this stream.
nsCOMPtr<nsIStreamTransportService> sts =
do_GetService(kStreamTransportServiceCID, &rv);
if (NS_FAILED(rv)) return rv;
nsCOMPtr<nsITransport> transport;
rv = sts->CreateInputTransport(mStream, mCloseWhenDone,
getter_AddRefs(transport));
if (NS_FAILED(rv)) return rv;
nsCOMPtr<nsIInputStream> wrapper;
rv = transport->OpenInputStream(0, mSegSize, mSegCount,
getter_AddRefs(wrapper));
if (NS_FAILED(rv)) return rv;
mAsyncStream = do_QueryInterface(wrapper, &rv);
if (NS_FAILED(rv)) return rv;
}
// release our reference to the original stream. from this point forward,
// we only reference the "stream" via mAsyncStream.
mStream = nullptr;
// mStreamOffset now holds the number of bytes currently read.
mStreamOffset = 0;
// grab event queue (we must do this here by contract, since all notifications
// must go to the thread which called AsyncRead)
if (NS_IsMainThread() && mLabeledMainThreadTarget) {
mTargetThread = mLabeledMainThreadTarget;
} else {
mTargetThread = GetCurrentThreadEventTarget();
}
NS_ENSURE_STATE(mTargetThread);
rv = EnsureWaiting();
if (NS_FAILED(rv)) return rv;
if (mLoadGroup) mLoadGroup->AddRequest(this, nullptr);
mState = STATE_START;
mListener = listener;
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsInputStreamPump::nsIInputStreamCallback implementation
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsInputStreamPump::OnInputStreamReady(nsIAsyncInputStream* stream) {
LOG(("nsInputStreamPump::OnInputStreamReady [this=%p]\n", this));
AUTO_PROFILER_LABEL("nsInputStreamPump::OnInputStreamReady", NETWORK);
// this function has been called from a PLEvent, so we can safely call
// any listener or progress sink methods directly from here.
for (;;) {
// There should only be one iteration of this loop happening at a time.
// To prevent AsyncWait() (called during callbacks or on other threads)
// from creating a parallel OnInputStreamReady(), we use:
// -- a mutex; and
// -- a boolean mProcessingCallbacks to detect parallel loops
// when exiting the mutex for callbacks.
RecursiveMutexAutoLock lock(mMutex);
// Prevent parallel execution during callbacks, while out of mutex.
if (mProcessingCallbacks) {
MOZ_ASSERT(!mProcessingCallbacks);
break;
}
mProcessingCallbacks = true;
if (mSuspendCount || mState == STATE_IDLE) {
mWaitingForInputStreamReady = false;
mProcessingCallbacks = false;
break;
}
uint32_t nextState;
switch (mState) {
case STATE_START:
nextState = OnStateStart();
break;
case STATE_TRANSFER:
nextState = OnStateTransfer();
break;
case STATE_STOP:
mRetargeting = false;
nextState = OnStateStop();
break;
default:
nextState = 0;
MOZ_ASSERT_UNREACHABLE("Unknown enum value.");
return NS_ERROR_UNEXPECTED;
}
bool stillTransferring =
(mState == STATE_TRANSFER && nextState == STATE_TRANSFER);
if (stillTransferring) {
NS_ASSERTION(NS_SUCCEEDED(mStatus),
"Should not have failed status for ongoing transfer");
} else {
NS_ASSERTION(mState != nextState,
"Only OnStateTransfer can be called more than once.");
}
if (mRetargeting) {
NS_ASSERTION(mState != STATE_STOP,
"Retargeting should not happen during OnStateStop.");
}
// Set mRetargeting so EnsureWaiting will be called. It ensures that
// OnStateStop is called on the main thread.
if (nextState == STATE_STOP && !NS_IsMainThread()) {
mRetargeting = true;
}
// Unset mProcessingCallbacks here (while we have lock) so our own call to
// EnsureWaiting isn't blocked by it.
mProcessingCallbacks = false;
// We must break the loop if suspended during one of the previous
// operation.
if (mSuspendCount) {
mState = nextState;
mWaitingForInputStreamReady = false;
break;
}
// Wait asynchronously if there is still data to transfer, or we're
// switching event delivery to another thread.
if (stillTransferring || mRetargeting) {
mState = nextState;
mWaitingForInputStreamReady = false;
nsresult rv = EnsureWaiting();
if (NS_SUCCEEDED(rv)) break;
// Failure to start asynchronous wait: stop transfer.
// Do not set mStatus if it was previously set to report a failure.
if (NS_SUCCEEDED(mStatus)) {
mStatus = rv;
}
nextState = STATE_STOP;
}
mState = nextState;
}
return NS_OK;
}
uint32_t nsInputStreamPump::OnStateStart() {
mMutex.AssertCurrentThreadIn();
AUTO_PROFILER_LABEL("nsInputStreamPump::OnStateStart", NETWORK);
LOG((" OnStateStart [this=%p]\n", this));
nsresult rv;
// need to check the reason why the stream is ready. this is required
// so our listener can check our status from OnStartRequest.
// XXX async streams should have a GetStatus method!
if (NS_SUCCEEDED(mStatus)) {
uint64_t avail;
rv = mAsyncStream->Available(&avail);
if (NS_FAILED(rv) && rv != NS_BASE_STREAM_CLOSED) mStatus = rv;
}
{
// Note: Must exit mutex for call to OnStartRequest to avoid
// deadlocks when calls to RetargetDeliveryTo for multiple
// nsInputStreamPumps are needed (e.g. nsHttpChannel).
RecursiveMutexAutoUnlock unlock(mMutex);
rv = mListener->OnStartRequest(this);
}
// an error returned from OnStartRequest should cause us to abort; however,
// we must not stomp on mStatus if already canceled.
if (NS_FAILED(rv) && NS_SUCCEEDED(mStatus)) mStatus = rv;
return NS_SUCCEEDED(mStatus) ? STATE_TRANSFER : STATE_STOP;
}
uint32_t nsInputStreamPump::OnStateTransfer() {
mMutex.AssertCurrentThreadIn();
AUTO_PROFILER_LABEL("nsInputStreamPump::OnStateTransfer", NETWORK);
LOG((" OnStateTransfer [this=%p]\n", this));
// if canceled, go directly to STATE_STOP...
if (NS_FAILED(mStatus)) return STATE_STOP;
nsresult rv = CreateBufferedStreamIfNeeded();
if (NS_WARN_IF(NS_FAILED(rv))) {
return STATE_STOP;
}
uint64_t avail;
rv = mAsyncStream->Available(&avail);
LOG((" Available returned [stream=%p rv=%" PRIx32 " avail=%" PRIu64 "]\n",
mAsyncStream.get(), static_cast<uint32_t>(rv), avail));
if (rv == NS_BASE_STREAM_CLOSED) {
rv = NS_OK;
avail = 0;
} else if (NS_SUCCEEDED(rv) && avail) {
// we used to limit avail to 16K - we were afraid some ODA handlers
// might assume they wouldn't get more than 16K at once
// we're removing that limit since it speeds up local file access.
// Now there's an implicit 64K limit of 4 16K segments
// NOTE: ok, so the story is as follows. OnDataAvailable impls
// are by contract supposed to consume exactly |avail| bytes.
// however, many do not... mailnews... stream converters...
// cough, cough. the input stream pump is fairly tolerant
// in this regard; however, if an ODA does not consume any
// data from the stream, then we could potentially end up in
// an infinite loop. we do our best here to try to catch
// such an error. (see bug 189672)
// in most cases this QI will succeed (mAsyncStream is almost always
// a nsPipeInputStream, which implements nsITellableStream::Tell).
int64_t offsetBefore;
nsCOMPtr<nsITellableStream> tellable = do_QueryInterface(mAsyncStream);
if (tellable && NS_FAILED(tellable->Tell(&offsetBefore))) {
MOZ_ASSERT_UNREACHABLE("Tell failed on readable stream");
offsetBefore = 0;
}
uint32_t odaAvail = avail > UINT32_MAX ? UINT32_MAX : uint32_t(avail);
LOG((" calling OnDataAvailable [offset=%" PRIu64 " count=%" PRIu64
"(%u)]\n",
mStreamOffset, avail, odaAvail));
{
// Note: Must exit mutex for call to OnStartRequest to avoid
// deadlocks when calls to RetargetDeliveryTo for multiple
// nsInputStreamPumps are needed (e.g. nsHttpChannel).
RecursiveMutexAutoUnlock unlock(mMutex);
rv = mListener->OnDataAvailable(this, mAsyncStream, mStreamOffset,
odaAvail);
}
// don't enter this code if ODA failed or called Cancel
if (NS_SUCCEEDED(rv) && NS_SUCCEEDED(mStatus)) {
// test to see if this ODA failed to consume data
if (tellable) {
// NOTE: if Tell fails, which can happen if the stream is
// now closed, then we assume that everything was read.
int64_t offsetAfter;
if (NS_FAILED(tellable->Tell(&offsetAfter)))
offsetAfter = offsetBefore + odaAvail;
if (offsetAfter > offsetBefore)
mStreamOffset += (offsetAfter - offsetBefore);
else if (mSuspendCount == 0) {
//
// possible infinite loop if we continue pumping data!
//
// NOTE: although not allowed by nsIStreamListener, we
// will allow the ODA impl to Suspend the pump. IMAP
// does this :-(
//
NS_ERROR("OnDataAvailable implementation consumed no data");
mStatus = NS_ERROR_UNEXPECTED;
}
} else
mStreamOffset += odaAvail; // assume ODA behaved well
}
}
// an error returned from Available or OnDataAvailable should cause us to
// abort; however, we must not stop on mStatus if already canceled.
if (NS_SUCCEEDED(mStatus)) {
if (NS_FAILED(rv))
mStatus = rv;
else if (avail) {
// if stream is now closed, advance to STATE_STOP right away.
// Available may return 0 bytes available at the moment; that
// would not mean that we are done.
// XXX async streams should have a GetStatus method!
rv = mAsyncStream->Available(&avail);
if (NS_SUCCEEDED(rv)) return STATE_TRANSFER;
if (rv != NS_BASE_STREAM_CLOSED) mStatus = rv;
}
}
return STATE_STOP;
}
nsresult nsInputStreamPump::CallOnStateStop() {
RecursiveMutexAutoLock lock(mMutex);
MOZ_ASSERT(NS_IsMainThread(),
"CallOnStateStop should only be called on the main thread.");
mState = OnStateStop();
return NS_OK;
}
uint32_t nsInputStreamPump::OnStateStop() {
mMutex.AssertCurrentThreadIn();
if (!NS_IsMainThread()) {
// This method can be called on a different thread if nsInputStreamPump
// is used off the main-thread.
nsresult rv = mLabeledMainThreadTarget->Dispatch(
NewRunnableMethod("nsInputStreamPump::CallOnStateStop", this,
&nsInputStreamPump::CallOnStateStop));
NS_ENSURE_SUCCESS(rv, STATE_IDLE);
return STATE_IDLE;
}
AUTO_PROFILER_LABEL("nsInputStreamPump::OnStateStop", NETWORK);
LOG((" OnStateStop [this=%p status=%" PRIx32 "]\n", this,
static_cast<uint32_t>(mStatus)));
// if an error occurred, we must be sure to pass the error onto the async
// stream. in some cases, this is redundant, but since close is idempotent,
// this is OK. otherwise, be sure to honor the "close-when-done" option.
if (!mAsyncStream || !mListener) {
MOZ_ASSERT(mAsyncStream, "null mAsyncStream: OnStateStop called twice?");
MOZ_ASSERT(mListener, "null mListener: OnStateStop called twice?");
return STATE_IDLE;
}
if (NS_FAILED(mStatus))
mAsyncStream->CloseWithStatus(mStatus);
else if (mCloseWhenDone)
mAsyncStream->Close();
mAsyncStream = nullptr;
mTargetThread = nullptr;
mIsPending = false;
{
// Note: Must exit mutex for call to OnStartRequest to avoid
// deadlocks when calls to RetargetDeliveryTo for multiple
// nsInputStreamPumps are needed (e.g. nsHttpChannel).
RecursiveMutexAutoUnlock unlock(mMutex);
mListener->OnStopRequest(this, mStatus);
}
mListener = nullptr;
if (mLoadGroup) mLoadGroup->RemoveRequest(this, nullptr, mStatus);
return STATE_IDLE;
}
nsresult nsInputStreamPump::CreateBufferedStreamIfNeeded() {
if (mAsyncStreamIsBuffered) {
return NS_OK;
}
// ReadSegments is not available for any nsIAsyncInputStream. In order to use
// it, we wrap a nsIBufferedInputStream around it, if needed.
if (NS_InputStreamIsBuffered(mAsyncStream)) {
mAsyncStreamIsBuffered = true;
return NS_OK;
}
nsCOMPtr<nsIInputStream> stream;
nsresult rv = NS_NewBufferedInputStream(getter_AddRefs(stream),
mAsyncStream.forget(), 4096);
NS_ENSURE_SUCCESS(rv, rv);
// A buffered inputStream must implement nsIAsyncInputStream.
mAsyncStream = do_QueryInterface(stream);
MOZ_DIAGNOSTIC_ASSERT(mAsyncStream);
mAsyncStreamIsBuffered = true;
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsIThreadRetargetableRequest
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsInputStreamPump::RetargetDeliveryTo(nsIEventTarget* aNewTarget) {
RecursiveMutexAutoLock lock(mMutex);
NS_ENSURE_ARG(aNewTarget);
NS_ENSURE_TRUE(mState == STATE_START || mState == STATE_TRANSFER,
NS_ERROR_UNEXPECTED);
// If canceled, do not retarget. Return with canceled status.
if (NS_FAILED(mStatus)) {
return mStatus;
}
if (aNewTarget == mTargetThread) {
NS_WARNING("Retargeting delivery to same thread");
return NS_OK;
}
// Ensure that |mListener| and any subsequent listeners can be retargeted
// to another thread.
nsresult rv = NS_OK;
nsCOMPtr<nsIThreadRetargetableStreamListener> retargetableListener =
do_QueryInterface(mListener, &rv);
if (NS_SUCCEEDED(rv) && retargetableListener) {
rv = retargetableListener->CheckListenerChain();
if (NS_SUCCEEDED(rv)) {
mTargetThread = aNewTarget;
mRetargeting = true;
}
}
LOG(
("nsInputStreamPump::RetargetDeliveryTo [this=%p aNewTarget=%p] "
"%s listener [%p] rv[%" PRIx32 "]",
this, aNewTarget, (mTargetThread == aNewTarget ? "success" : "failure"),
(nsIStreamListener*)mListener, static_cast<uint32_t>(rv)));
return rv;
}
NS_IMETHODIMP
nsInputStreamPump::GetDeliveryTarget(nsIEventTarget** aNewTarget) {
RecursiveMutexAutoLock lock(mMutex);
nsCOMPtr<nsIEventTarget> target = mTargetThread;
target.forget(aNewTarget);
return NS_OK;
}
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