diff options
Diffstat (limited to 'dom/fetch/FetchStreamReader.cpp')
| -rw-r--r-- | dom/fetch/FetchStreamReader.cpp | 441 |
1 files changed, 441 insertions, 0 deletions
diff --git a/dom/fetch/FetchStreamReader.cpp b/dom/fetch/FetchStreamReader.cpp new file mode 100644 index 0000000000..de5a2cfefe --- /dev/null +++ b/dom/fetch/FetchStreamReader.cpp @@ -0,0 +1,441 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* 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 "FetchStreamReader.h" +#include "InternalResponse.h" +#include "mozilla/ConsoleReportCollector.h" +#include "mozilla/ErrorResult.h" +#include "mozilla/StaticAnalysisFunctions.h" +#include "mozilla/dom/AutoEntryScript.h" +#include "mozilla/dom/Promise.h" +#include "mozilla/dom/PromiseBinding.h" +#include "mozilla/dom/ReadableStream.h" +#include "mozilla/dom/ReadableStreamDefaultController.h" +#include "mozilla/dom/ReadableStreamDefaultReader.h" +#include "mozilla/dom/WorkerPrivate.h" +#include "mozilla/dom/WorkerRef.h" +#include "mozilla/HoldDropJSObjects.h" +#include "mozilla/TaskCategory.h" +#include "nsContentUtils.h" +#include "nsDebug.h" +#include "nsIAsyncInputStream.h" +#include "nsIPipe.h" +#include "nsIScriptError.h" +#include "nsPIDOMWindow.h" +#include "jsapi.h" + +namespace mozilla::dom { + +NS_IMPL_CYCLE_COLLECTING_ADDREF(FetchStreamReader) +NS_IMPL_CYCLE_COLLECTING_RELEASE(FetchStreamReader) + +NS_IMPL_CYCLE_COLLECTION_CLASS(FetchStreamReader) + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(FetchStreamReader) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mGlobal) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mReader) +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(FetchStreamReader) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mGlobal) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mReader) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(FetchStreamReader) +NS_IMPL_CYCLE_COLLECTION_TRACE_END + +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FetchStreamReader) + NS_INTERFACE_MAP_ENTRY(nsIOutputStreamCallback) + NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIOutputStreamCallback) +NS_INTERFACE_MAP_END + +/* static */ +nsresult FetchStreamReader::Create(JSContext* aCx, nsIGlobalObject* aGlobal, + FetchStreamReader** aStreamReader, + nsIInputStream** aInputStream) { + MOZ_ASSERT(aCx); + MOZ_ASSERT(aGlobal); + MOZ_ASSERT(aStreamReader); + MOZ_ASSERT(aInputStream); + + RefPtr<FetchStreamReader> streamReader = new FetchStreamReader(aGlobal); + + nsCOMPtr<nsIAsyncInputStream> pipeIn; + + NS_NewPipe2(getter_AddRefs(pipeIn), getter_AddRefs(streamReader->mPipeOut), + true, true, 0, 0); + + if (!NS_IsMainThread()) { + WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(aCx); + MOZ_ASSERT(workerPrivate); + + RefPtr<StrongWorkerRef> workerRef = StrongWorkerRef::Create( + workerPrivate, "FetchStreamReader", [streamReader]() { + MOZ_ASSERT(streamReader); + + // mAsyncWaitWorkerRef may keep the (same) StrongWorkerRef alive even + // when mWorkerRef has already been nulled out by a previous call to + // CloseAndRelease, we can just safely ignore this callback then + // (as would the CloseAndRelease do on a second call). + if (streamReader->mWorkerRef) { + streamReader->CloseAndRelease( + streamReader->mWorkerRef->Private()->GetJSContext(), + NS_ERROR_DOM_INVALID_STATE_ERR); + } else { + MOZ_DIAGNOSTIC_ASSERT(streamReader->mAsyncWaitWorkerRef); + } + }); + + if (NS_WARN_IF(!workerRef)) { + streamReader->mPipeOut->CloseWithStatus(NS_ERROR_DOM_INVALID_STATE_ERR); + return NS_ERROR_DOM_INVALID_STATE_ERR; + } + + // These 2 objects create a ref-cycle here that is broken when the stream is + // closed or the worker shutsdown. + streamReader->mWorkerRef = std::move(workerRef); + } + + pipeIn.forget(aInputStream); + streamReader.forget(aStreamReader); + return NS_OK; +} + +FetchStreamReader::FetchStreamReader(nsIGlobalObject* aGlobal) + : mGlobal(aGlobal), + mOwningEventTarget(mGlobal->EventTargetFor(TaskCategory::Other)) { + MOZ_ASSERT(aGlobal); + + mozilla::HoldJSObjects(this); +} + +FetchStreamReader::~FetchStreamReader() { + CloseAndRelease(nullptr, NS_BASE_STREAM_CLOSED); + + mozilla::DropJSObjects(this); +} + +// If a context is provided, an attempt will be made to cancel the reader. The +// only situation where we don't expect to have a context is when closure is +// being triggered from the destructor or the WorkerRef is notifying. If +// we're at the destructor, it's far too late to cancel anything. And if the +// WorkerRef is being notified, the global is going away, so there's also +// no need to do further JS work. +void FetchStreamReader::CloseAndRelease(JSContext* aCx, nsresult aStatus) { + NS_ASSERT_OWNINGTHREAD(FetchStreamReader); + + if (mStreamClosed) { + // Already closed. + return; + } + + RefPtr<FetchStreamReader> kungFuDeathGrip = this; + if (aCx && mReader) { + ErrorResult rv; + if (aStatus == NS_ERROR_DOM_WRONG_TYPE_ERR) { + rv.ThrowTypeError<MSG_FETCH_BODY_WRONG_TYPE>(); + } else { + rv = aStatus; + } + JS::Rooted<JS::Value> errorValue(aCx); + if (ToJSValue(aCx, std::move(rv), &errorValue)) { + IgnoredErrorResult ignoredError; + // It's currently safe to cancel an already closed reader because, per the + // comments in ReadableStream::cancel() conveying the spec, step 2 of + // 3.4.3 that specified ReadableStreamCancel is: If stream.[[state]] is + // "closed", return a new promise resolved with undefined. + RefPtr<Promise> cancelResultPromise = + MOZ_KnownLive(mReader)->Cancel(aCx, errorValue, ignoredError); + NS_WARNING_ASSERTION(!ignoredError.Failed(), + "Failed to cancel stream during close and release"); + if (cancelResultPromise) { + bool setHandled = cancelResultPromise->SetAnyPromiseIsHandled(); + NS_WARNING_ASSERTION(setHandled, + "Failed to mark cancel promise as handled."); + (void)setHandled; + } + } + + // We don't want to propagate exceptions during the cleanup. + JS_ClearPendingException(aCx); + } + + mStreamClosed = true; + + mGlobal = nullptr; + + if (mPipeOut) { + mPipeOut->CloseWithStatus(aStatus); + } + mPipeOut = nullptr; + + mWorkerRef = nullptr; + + mReader = nullptr; + mBuffer.Clear(); +} + +// https://fetch.spec.whatwg.org/#body-incrementally-read +void FetchStreamReader::StartConsuming(JSContext* aCx, ReadableStream* aStream, + ErrorResult& aRv) { + MOZ_DIAGNOSTIC_ASSERT(!mReader); + MOZ_DIAGNOSTIC_ASSERT(aStream); + + // Step 2: Let reader be the result of getting a reader for body’s stream. + RefPtr<ReadableStreamDefaultReader> reader = aStream->GetReader(aRv); + if (aRv.Failed()) { + CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR); + return; + } + + mReader = reader; + + mAsyncWaitWorkerRef = mWorkerRef; + aRv = mPipeOut->AsyncWait(this, 0, 0, mOwningEventTarget); + if (NS_WARN_IF(aRv.Failed())) { + mAsyncWaitWorkerRef = nullptr; + CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR); + } +} + +struct FetchReadRequest : public ReadRequest { + public: + NS_DECL_ISUPPORTS_INHERITED + NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(FetchReadRequest, ReadRequest) + + explicit FetchReadRequest(FetchStreamReader* aReader) + : mFetchStreamReader(aReader) {} + + MOZ_CAN_RUN_SCRIPT_BOUNDARY + void ChunkSteps(JSContext* aCx, JS::Handle<JS::Value> aChunk, + ErrorResult& aRv) override { + mFetchStreamReader->ChunkSteps(aCx, aChunk, aRv); + } + + MOZ_CAN_RUN_SCRIPT_BOUNDARY + void CloseSteps(JSContext* aCx, ErrorResult& aRv) override { + mFetchStreamReader->CloseSteps(aCx, aRv); + } + + MOZ_CAN_RUN_SCRIPT_BOUNDARY + void ErrorSteps(JSContext* aCx, JS::Handle<JS::Value> aError, + ErrorResult& aRv) override { + mFetchStreamReader->ErrorSteps(aCx, aError, aRv); + } + + protected: + virtual ~FetchReadRequest() = default; + + MOZ_KNOWN_LIVE RefPtr<FetchStreamReader> mFetchStreamReader; +}; + +NS_IMPL_CYCLE_COLLECTION_INHERITED(FetchReadRequest, ReadRequest, + mFetchStreamReader) +NS_IMPL_ADDREF_INHERITED(FetchReadRequest, ReadRequest) +NS_IMPL_RELEASE_INHERITED(FetchReadRequest, ReadRequest) +NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FetchReadRequest) +NS_INTERFACE_MAP_END_INHERITING(ReadRequest) + +// nsIOutputStreamCallback interface +MOZ_CAN_RUN_SCRIPT_BOUNDARY +NS_IMETHODIMP +FetchStreamReader::OnOutputStreamReady(nsIAsyncOutputStream* aStream) { + NS_ASSERT_OWNINGTHREAD(FetchStreamReader); + if (mStreamClosed) { + mAsyncWaitWorkerRef = nullptr; + return NS_OK; + } + + AutoEntryScript aes(mGlobal, "ReadableStreamReader.read", !mWorkerRef); + if (!Process(aes.cx())) { + // We're done processing data, and haven't queued up a new AsyncWait - we + // can clear our mAsyncWaitWorkerRef. + mAsyncWaitWorkerRef = nullptr; + } + return NS_OK; +} + +bool FetchStreamReader::Process(JSContext* aCx) { + NS_ASSERT_OWNINGTHREAD(FetchStreamReader); + MOZ_ASSERT(mReader); + + if (!mBuffer.IsEmpty()) { + nsresult rv = WriteBuffer(); + if (NS_WARN_IF(NS_FAILED(rv))) { + CloseAndRelease(aCx, NS_ERROR_DOM_ABORT_ERR); + return false; + } + return true; + } + + // Check if the output stream has already been closed. This lets us propagate + // errors eagerly, and detect output stream closures even when we have no data + // to write. + if (NS_WARN_IF(NS_FAILED(mPipeOut->StreamStatus()))) { + CloseAndRelease(aCx, NS_ERROR_DOM_ABORT_ERR); + return false; + } + + // We're waiting on new data - set up a WAIT_CLOSURE_ONLY callback so we + // notice if the reader closes. + nsresult rv = mPipeOut->AsyncWait( + this, nsIAsyncOutputStream::WAIT_CLOSURE_ONLY, 0, mOwningEventTarget); + if (NS_WARN_IF(NS_FAILED(rv))) { + CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR); + return false; + } + + // If we already have an outstanding read request, don't start another one + // concurrently. + if (!mHasOutstandingReadRequest) { + // https://fetch.spec.whatwg.org/#incrementally-read-loop + // The below very loosely tries to implement the incrementally-read-loop + // from the fetch spec. + // Step 2: Read a chunk from reader given readRequest. + RefPtr<ReadRequest> readRequest = new FetchReadRequest(this); + RefPtr<ReadableStreamDefaultReader> reader = mReader; + mHasOutstandingReadRequest = true; + + IgnoredErrorResult err; + reader->ReadChunk(aCx, *readRequest, err); + if (NS_WARN_IF(err.Failed())) { + // Let's close the stream. + mHasOutstandingReadRequest = false; + CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR); + // Don't return false, as we've already called `AsyncWait`. + } + } + return true; +} + +void FetchStreamReader::ChunkSteps(JSContext* aCx, JS::Handle<JS::Value> aChunk, + ErrorResult& aRv) { + // This roughly implements the chunk steps from + // https://fetch.spec.whatwg.org/#incrementally-read-loop. + + mHasOutstandingReadRequest = false; + + // Step 2. If chunk is not a Uint8Array object, then set continueAlgorithm to + // this step: run processBodyError given a TypeError. + RootedSpiderMonkeyInterface<Uint8Array> chunk(aCx); + if (!aChunk.isObject() || !chunk.Init(&aChunk.toObject())) { + CloseAndRelease(aCx, NS_ERROR_DOM_WRONG_TYPE_ERR); + return; + } + chunk.ComputeState(); + + MOZ_DIAGNOSTIC_ASSERT(mBuffer.IsEmpty()); + + // Let's take a copy of the data. + // FIXME: We could sometimes avoid this copy by trying to write `chunk` + // directly into `mPipeOut` eagerly, and only filling `mBuffer` if there isn't + // enough space in the pipe's buffer. + if (!mBuffer.AppendElements(chunk.Data(), chunk.Length(), fallible)) { + CloseAndRelease(aCx, NS_ERROR_OUT_OF_MEMORY); + return; + } + + mBufferOffset = 0; + mBufferRemaining = chunk.Length(); + + nsresult rv = WriteBuffer(); + if (NS_WARN_IF(NS_FAILED(rv))) { + CloseAndRelease(aCx, NS_ERROR_DOM_ABORT_ERR); + } +} + +void FetchStreamReader::CloseSteps(JSContext* aCx, ErrorResult& aRv) { + mHasOutstandingReadRequest = false; + CloseAndRelease(aCx, NS_BASE_STREAM_CLOSED); +} + +void FetchStreamReader::ErrorSteps(JSContext* aCx, JS::Handle<JS::Value> aError, + ErrorResult& aRv) { + mHasOutstandingReadRequest = false; + ReportErrorToConsole(aCx, aError); + CloseAndRelease(aCx, NS_ERROR_FAILURE); +} + +nsresult FetchStreamReader::WriteBuffer() { + MOZ_ASSERT(mBuffer.Length() == (mBufferOffset + mBufferRemaining)); + + char* data = reinterpret_cast<char*>(mBuffer.Elements()); + + while (mBufferRemaining > 0) { + uint32_t written = 0; + nsresult rv = + mPipeOut->Write(data + mBufferOffset, mBufferRemaining, &written); + + if (rv == NS_BASE_STREAM_WOULD_BLOCK) { + break; + } + + if (NS_WARN_IF(NS_FAILED(rv))) { + return rv; + } + + MOZ_ASSERT(written <= mBufferRemaining); + mBufferRemaining -= written; + mBufferOffset += written; + + if (mBufferRemaining == 0) { + mBuffer.Clear(); + break; + } + } + + nsresult rv = mPipeOut->AsyncWait(this, 0, 0, mOwningEventTarget); + if (NS_WARN_IF(NS_FAILED(rv))) { + return rv; + } + + return NS_OK; +} + +void FetchStreamReader::ReportErrorToConsole(JSContext* aCx, + JS::Handle<JS::Value> aValue) { + nsCString sourceSpec; + uint32_t line = 0; + uint32_t column = 0; + nsString valueString; + + nsContentUtils::ExtractErrorValues(aCx, aValue, sourceSpec, &line, &column, + valueString); + + nsTArray<nsString> params; + params.AppendElement(valueString); + + RefPtr<ConsoleReportCollector> reporter = new ConsoleReportCollector(); + reporter->AddConsoleReport(nsIScriptError::errorFlag, + "ReadableStreamReader.read"_ns, + nsContentUtils::eDOM_PROPERTIES, sourceSpec, line, + column, "ReadableStreamReadingFailed"_ns, params); + + uint64_t innerWindowId = 0; + + if (NS_IsMainThread()) { + nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(mGlobal); + if (window) { + innerWindowId = window->WindowID(); + } + reporter->FlushReportsToConsole(innerWindowId); + return; + } + + WorkerPrivate* workerPrivate = GetWorkerPrivateFromContext(aCx); + if (workerPrivate) { + innerWindowId = workerPrivate->WindowID(); + } + + RefPtr<Runnable> r = NS_NewRunnableFunction( + "FetchStreamReader::ReportErrorToConsole", [reporter, innerWindowId]() { + reporter->FlushReportsToConsole(innerWindowId); + }); + + workerPrivate->DispatchToMainThread(r.forget()); +} + +} // namespace mozilla::dom |