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-rw-r--r--dom/streams/ReadableByteStreamController.cpp2087
1 files changed, 2087 insertions, 0 deletions
diff --git a/dom/streams/ReadableByteStreamController.cpp b/dom/streams/ReadableByteStreamController.cpp
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+++ b/dom/streams/ReadableByteStreamController.cpp
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 "mozilla/dom/ReadableByteStreamController.h"
+
+#include "ReadIntoRequest.h"
+#include "js/ArrayBuffer.h"
+#include "js/ErrorReport.h"
+#include "js/Exception.h"
+#include "js/TypeDecls.h"
+#include "js/Value.h"
+#include "js/ValueArray.h"
+#include "js/experimental/TypedData.h"
+#include "js/friend/ErrorMessages.h"
+#include "mozilla/AlreadyAddRefed.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/ErrorResult.h"
+#include "mozilla/HoldDropJSObjects.h"
+#include "mozilla/dom/ByteStreamHelpers.h"
+#include "mozilla/dom/Promise.h"
+#include "mozilla/dom/Promise-inl.h"
+#include "mozilla/dom/ReadableByteStreamControllerBinding.h"
+#include "mozilla/dom/ReadableStream.h"
+#include "mozilla/dom/ReadableStreamBYOBReader.h"
+#include "mozilla/dom/ReadableStreamBYOBRequest.h"
+#include "mozilla/dom/ReadableStreamController.h"
+#include "mozilla/dom/ReadableStreamDefaultController.h"
+#include "mozilla/dom/ReadableStreamDefaultReader.h"
+#include "mozilla/dom/ReadableStreamGenericReader.h"
+#include "mozilla/dom/ToJSValue.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "mozilla/dom/UnderlyingSourceCallbackHelpers.h"
+#include "nsCycleCollectionParticipant.h"
+#include "nsIGlobalObject.h"
+#include "nsISupports.h"
+
+#include <algorithm> // std::min
+
+namespace mozilla::dom {
+
+using namespace streams_abstract;
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-queue-entry
+struct ReadableByteStreamQueueEntry
+ : LinkedListElement<RefPtr<ReadableByteStreamQueueEntry>> {
+ NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(
+ ReadableByteStreamQueueEntry)
+ NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(
+ ReadableByteStreamQueueEntry)
+
+ ReadableByteStreamQueueEntry(JS::Handle<JSObject*> aBuffer,
+ size_t aByteOffset, size_t aByteLength)
+ : mBuffer(aBuffer), mByteOffset(aByteOffset), mByteLength(aByteLength) {
+ mozilla::HoldJSObjects(this);
+ }
+
+ JSObject* Buffer() const { return mBuffer; }
+ void SetBuffer(JS::Handle<JSObject*> aBuffer) { mBuffer = aBuffer; }
+
+ size_t ByteOffset() const { return mByteOffset; }
+ void SetByteOffset(size_t aByteOffset) { mByteOffset = aByteOffset; }
+
+ size_t ByteLength() const { return mByteLength; }
+ void SetByteLength(size_t aByteLength) { mByteLength = aByteLength; }
+
+ private:
+ // An ArrayBuffer, which will be a transferred version of the one originally
+ // supplied by the underlying byte source.
+ JS::Heap<JSObject*> mBuffer;
+
+ // A nonnegative integer number giving the byte offset derived from the view
+ // originally supplied by the underlying byte source
+ size_t mByteOffset = 0;
+
+ // A nonnegative integer number giving the byte length derived from the view
+ // originally supplied by the underlying byte source
+ size_t mByteLength = 0;
+
+ ~ReadableByteStreamQueueEntry() { mozilla::DropJSObjects(this); }
+};
+
+NS_IMPL_CYCLE_COLLECTION_WITH_JS_MEMBERS(ReadableByteStreamQueueEntry, (),
+ (mBuffer));
+
+struct PullIntoDescriptor final
+ : LinkedListElement<RefPtr<PullIntoDescriptor>> {
+ NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(PullIntoDescriptor)
+ NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(PullIntoDescriptor)
+
+ enum Constructor {
+ DataView,
+#define DEFINE_TYPED_CONSTRUCTOR_ENUM_NAMES(ExternalT, NativeT, Name) Name,
+ JS_FOR_EACH_TYPED_ARRAY(DEFINE_TYPED_CONSTRUCTOR_ENUM_NAMES)
+#undef DEFINE_TYPED_CONSTRUCTOR_ENUM_NAMES
+ };
+
+ static Constructor constructorFromScalar(JS::Scalar::Type type) {
+ switch (type) {
+#define REMAP_PULL_INTO_DESCRIPTOR_TYPE(ExternalT, NativeT, Name) \
+ case JS::Scalar::Name: \
+ return Constructor::Name;
+ JS_FOR_EACH_TYPED_ARRAY(REMAP_PULL_INTO_DESCRIPTOR_TYPE)
+#undef REMAP
+
+ case JS::Scalar::Int64:
+ case JS::Scalar::Simd128:
+ case JS::Scalar::MaxTypedArrayViewType:
+ break;
+ }
+ MOZ_CRASH("Unexpected Scalar::Type");
+ }
+
+ PullIntoDescriptor(JS::Handle<JSObject*> aBuffer, uint64_t aBufferByteLength,
+ uint64_t aByteOffset, uint64_t aByteLength,
+ uint64_t aBytesFilled, uint64_t aElementSize,
+ Constructor aViewConstructor, ReaderType aReaderType)
+ : mBuffer(aBuffer),
+ mBufferByteLength(aBufferByteLength),
+ mByteOffset(aByteOffset),
+ mByteLength(aByteLength),
+ mBytesFilled(aBytesFilled),
+ mElementSize(aElementSize),
+ mViewConstructor(aViewConstructor),
+ mReaderType(aReaderType) {
+ mozilla::HoldJSObjects(this);
+ }
+
+ JSObject* Buffer() const { return mBuffer; }
+ void SetBuffer(JS::Handle<JSObject*> aBuffer) { mBuffer = aBuffer; }
+
+ uint64_t BufferByteLength() const { return mBufferByteLength; }
+ void SetBufferByteLength(const uint64_t aBufferByteLength) {
+ mBufferByteLength = aBufferByteLength;
+ }
+
+ uint64_t ByteOffset() const { return mByteOffset; }
+ void SetByteOffset(const uint64_t aByteOffset) { mByteOffset = aByteOffset; }
+
+ uint64_t ByteLength() const { return mByteLength; }
+ void SetByteLength(const uint64_t aByteLength) { mByteLength = aByteLength; }
+
+ uint64_t BytesFilled() const { return mBytesFilled; }
+ void SetBytesFilled(const uint64_t aBytesFilled) {
+ mBytesFilled = aBytesFilled;
+ }
+
+ uint64_t ElementSize() const { return mElementSize; }
+ void SetElementSize(const uint64_t aElementSize) {
+ mElementSize = aElementSize;
+ }
+
+ Constructor ViewConstructor() const { return mViewConstructor; }
+
+ // Note: Named GetReaderType to avoid name conflict with type.
+ ReaderType GetReaderType() const { return mReaderType; }
+ void SetReaderType(const ReaderType aReaderType) {
+ mReaderType = aReaderType;
+ }
+
+ private:
+ JS::Heap<JSObject*> mBuffer;
+ uint64_t mBufferByteLength = 0;
+ uint64_t mByteOffset = 0;
+ uint64_t mByteLength = 0;
+ uint64_t mBytesFilled = 0;
+ uint64_t mElementSize = 0;
+ Constructor mViewConstructor;
+ ReaderType mReaderType;
+
+ ~PullIntoDescriptor() { mozilla::DropJSObjects(this); }
+};
+
+NS_IMPL_CYCLE_COLLECTION_WITH_JS_MEMBERS(PullIntoDescriptor, (), (mBuffer));
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(ReadableByteStreamController)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(ReadableByteStreamController,
+ ReadableStreamController)
+ NS_IMPL_CYCLE_COLLECTION_UNLINK(mByobRequest, mQueue, mPendingPullIntos)
+ NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(ReadableByteStreamController,
+ ReadableStreamController)
+ NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mByobRequest, mQueue, mPendingPullIntos)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN_INHERITED(ReadableByteStreamController,
+ ReadableStreamController)
+ NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_ADDREF_INHERITED(ReadableByteStreamController, ReadableStreamController)
+NS_IMPL_RELEASE_INHERITED(ReadableByteStreamController,
+ ReadableStreamController)
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ReadableByteStreamController)
+ NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+NS_INTERFACE_MAP_END_INHERITING(ReadableStreamController)
+
+ReadableByteStreamController::ReadableByteStreamController(
+ nsIGlobalObject* aGlobal)
+ : ReadableStreamController(aGlobal) {}
+
+ReadableByteStreamController::~ReadableByteStreamController() = default;
+
+void ReadableByteStreamController::ClearQueue() { mQueue.clear(); }
+
+void ReadableByteStreamController::ClearPendingPullIntos() {
+ mPendingPullIntos.clear();
+}
+
+namespace streams_abstract {
+// https://streams.spec.whatwg.org/#abstract-opdef-readablebytestreamcontrollergetbyobrequest
+already_AddRefed<ReadableStreamBYOBRequest>
+ReadableByteStreamControllerGetBYOBRequest(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1.
+ if (!aController->GetByobRequest() &&
+ !aController->PendingPullIntos().isEmpty()) {
+ // Step 1.1:
+ PullIntoDescriptor* firstDescriptor =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 1.2:
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> buffer(aCx, firstDescriptor->Buffer());
+ JS::Rooted<JSObject*> view(
+ aCx, JS_NewUint8ArrayWithBuffer(
+ aCx, buffer,
+ firstDescriptor->ByteOffset() + firstDescriptor->BytesFilled(),
+ int64_t(firstDescriptor->ByteLength() -
+ firstDescriptor->BytesFilled())));
+ if (!view) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return nullptr;
+ }
+
+ // Step 1.3:
+ RefPtr<ReadableStreamBYOBRequest> byobRequest =
+ new ReadableStreamBYOBRequest(aController->GetParentObject());
+
+ // Step 1.4:
+ byobRequest->SetController(aController);
+
+ // Step 1.5:
+ byobRequest->SetView(view);
+
+ // Step 1.6:
+ aController->SetByobRequest(byobRequest);
+ }
+
+ // Step 2.
+ RefPtr<ReadableStreamBYOBRequest> request(aController->GetByobRequest());
+ return request.forget();
+}
+} // namespace streams_abstract
+
+already_AddRefed<ReadableStreamBYOBRequest>
+ReadableByteStreamController::GetByobRequest(JSContext* aCx, ErrorResult& aRv) {
+ return ReadableByteStreamControllerGetBYOBRequest(aCx, this, aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-get-desired-size
+Nullable<double> ReadableByteStreamControllerGetDesiredSize(
+ const ReadableByteStreamController* aController) {
+ // Step 1.
+ ReadableStream::ReaderState state = aController->Stream()->State();
+
+ // Step 2.
+ if (state == ReadableStream::ReaderState::Errored) {
+ return nullptr;
+ }
+
+ // Step 3.
+ if (state == ReadableStream::ReaderState::Closed) {
+ return 0.0;
+ }
+
+ // Step 4.
+ return aController->StrategyHWM() - aController->QueueTotalSize();
+}
+
+Nullable<double> ReadableByteStreamController::GetDesiredSize() const {
+ // Step 1.
+ return ReadableByteStreamControllerGetDesiredSize(this);
+}
+
+JSObject* ReadableByteStreamController::WrapObject(
+ JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
+ return ReadableByteStreamController_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+namespace streams_abstract {
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-invalidate-byob-request
+static void ReadableByteStreamControllerInvalidateBYOBRequest(
+ ReadableByteStreamController* aController) {
+ // Step 1.
+ if (!aController->GetByobRequest()) {
+ return;
+ }
+
+ // Step 2.
+ aController->GetByobRequest()->SetController(nullptr);
+
+ // Step 3.
+ aController->GetByobRequest()->SetView(nullptr);
+
+ // Step 4.
+ aController->SetByobRequest(nullptr);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-clear-pending-pull-intos
+void ReadableByteStreamControllerClearPendingPullIntos(
+ ReadableByteStreamController* aController) {
+ // Step 1.
+ ReadableByteStreamControllerInvalidateBYOBRequest(aController);
+
+ // Step 2.
+ aController->ClearPendingPullIntos();
+}
+
+// https://streams.spec.whatwg.org/#reset-queue
+void ResetQueue(ReadableByteStreamController* aContainer) {
+ // Step 1. Implied by type.
+ // Step 2.
+ aContainer->ClearQueue();
+
+ // Step 3.
+ aContainer->SetQueueTotalSize(0);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-clear-algorithms
+void ReadableByteStreamControllerClearAlgorithms(
+ ReadableByteStreamController* aController) {
+ // Step 1. Set controller.[[pullAlgorithm]] to undefined.
+ // Step 2. Set controller.[[cancelAlgorithm]] to undefined.
+ aController->ClearAlgorithms();
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-error
+void ReadableByteStreamControllerError(
+ ReadableByteStreamController* aController, JS::Handle<JS::Value> aValue,
+ ErrorResult& aRv) {
+ // Step 1. Let stream be controller.[[stream]].
+ ReadableStream* stream = aController->Stream();
+
+ // Step 2. If stream.[[state]] is not "readable", return.
+ if (stream->State() != ReadableStream::ReaderState::Readable) {
+ return;
+ }
+
+ // Step 3. Perform
+ // !ReadableByteStreamControllerClearPendingPullIntos(controller).
+ ReadableByteStreamControllerClearPendingPullIntos(aController);
+
+ // Step 4. Perform !ResetQueue(controller).
+ ResetQueue(aController);
+
+ // Step 5. Perform !ReadableByteStreamControllerClearAlgorithms(controller).
+ ReadableByteStreamControllerClearAlgorithms(aController);
+
+ // Step 6. Perform !ReadableStreamError(stream, e).
+ AutoJSAPI jsapi;
+ if (!jsapi.Init(aController->GetParentObject())) {
+ return;
+ }
+ ReadableStreamError(jsapi.cx(), stream, aValue, aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-close
+void ReadableByteStreamControllerClose(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1.
+ RefPtr<ReadableStream> stream = aController->Stream();
+
+ // Step 2.
+ if (aController->CloseRequested() ||
+ stream->State() != ReadableStream::ReaderState::Readable) {
+ return;
+ }
+
+ // Step 3.
+ if (aController->QueueTotalSize() > 0) {
+ // Step 3.1
+ aController->SetCloseRequested(true);
+ // Step 3.2
+ return;
+ }
+
+ // Step 4.
+ if (!aController->PendingPullIntos().isEmpty()) {
+ // Step 4.1
+ PullIntoDescriptor* firstPendingPullInto =
+ aController->PendingPullIntos().getFirst();
+ // Step 4.2
+ if (firstPendingPullInto->BytesFilled() > 0) {
+ // Step 4.2.1
+ ErrorResult rv;
+ rv.ThrowTypeError("Leftover Bytes");
+
+ JS::Rooted<JS::Value> exception(aCx);
+ MOZ_ALWAYS_TRUE(ToJSValue(aCx, std::move(rv), &exception));
+
+ // Step 4.2.2
+ ReadableByteStreamControllerError(aController, exception, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ aRv.MightThrowJSException();
+ aRv.ThrowJSException(aCx, exception);
+ return;
+ }
+ }
+
+ // Step 5.
+ ReadableByteStreamControllerClearAlgorithms(aController);
+
+ // Step 6.
+ ReadableStreamClose(aCx, stream, aRv);
+}
+
+} // namespace streams_abstract
+
+// https://streams.spec.whatwg.org/#rbs-controller-close
+void ReadableByteStreamController::Close(JSContext* aCx, ErrorResult& aRv) {
+ // Step 1.
+ if (mCloseRequested) {
+ aRv.ThrowTypeError("Close already requested");
+ return;
+ }
+
+ // Step 2.
+ if (Stream()->State() != ReadableStream::ReaderState::Readable) {
+ aRv.ThrowTypeError("Closing un-readable stream controller");
+ return;
+ }
+
+ // Step 3.
+ ReadableByteStreamControllerClose(aCx, this, aRv);
+}
+
+namespace streams_abstract {
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-enqueue-chunk-to-queue
+void ReadableByteStreamControllerEnqueueChunkToQueue(
+ ReadableByteStreamController* aController,
+ JS::Handle<JSObject*> aTransferredBuffer, size_t aByteOffset,
+ size_t aByteLength) {
+ // Step 1.
+ RefPtr<ReadableByteStreamQueueEntry> queueEntry =
+ new ReadableByteStreamQueueEntry(aTransferredBuffer, aByteOffset,
+ aByteLength);
+ aController->Queue().insertBack(queueEntry);
+
+ // Step 2.
+ aController->AddToQueueTotalSize(double(aByteLength));
+}
+
+// https://streams.spec.whatwg.org/#abstract-opdef-readablebytestreamcontrollerenqueueclonedchunktoqueue
+void ReadableByteStreamControllerEnqueueClonedChunkToQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ JS::Handle<JSObject*> aBuffer, size_t aByteOffset, size_t aByteLength,
+ ErrorResult& aRv) {
+ // Step 1. Let cloneResult be CloneArrayBuffer(buffer, byteOffset, byteLength,
+ // %ArrayBuffer%).
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> cloneResult(
+ aCx, JS::ArrayBufferClone(aCx, aBuffer, aByteOffset, aByteLength));
+
+ // Step 2. If cloneResult is an abrupt completion,
+ if (!cloneResult) {
+ JS::Rooted<JS::Value> exception(aCx);
+ if (!JS_GetPendingException(aCx, &exception)) {
+ // Uncatchable exception; we should mark aRv and return.
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ JS_ClearPendingException(aCx);
+
+ // Step 2.1. Perform ! ReadableByteStreamControllerError(controller,
+ // cloneResult.[[Value]]).
+ ReadableByteStreamControllerError(aController, exception, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 2.2. Return cloneResult.
+ aRv.ThrowJSException(aCx, exception);
+ return;
+ }
+
+ // Step 3. Perform !
+ // ReadableByteStreamControllerEnqueueChunkToQueue(controller,
+ // cloneResult.[[Value]], 0, byteLength).
+ ReadableByteStreamControllerEnqueueChunkToQueue(aController, cloneResult, 0,
+ aByteLength);
+}
+
+already_AddRefed<PullIntoDescriptor>
+ReadableByteStreamControllerShiftPendingPullInto(
+ ReadableByteStreamController* aController);
+
+// https://streams.spec.whatwg.org/#abstract-opdef-readablebytestreamcontrollerenqueuedetachedpullintotoqueue
+void ReadableByteStreamControllerEnqueueDetachedPullIntoToQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ PullIntoDescriptor* aPullIntoDescriptor, ErrorResult& aRv) {
+ // Step 1. Assert: pullIntoDescriptor’s reader type is "none".
+ MOZ_ASSERT(aPullIntoDescriptor->GetReaderType() == ReaderType::None);
+
+ // Step 2. If pullIntoDescriptor’s bytes filled > 0,
+ // perform ? ReadableByteStreamControllerEnqueueClonedChunkToQueue(controller,
+ // pullIntoDescriptor’s buffer, pullIntoDescriptor’s byte offset,
+ // pullIntoDescriptor’s bytes filled).
+ if (aPullIntoDescriptor->BytesFilled() > 0) {
+ JS::Rooted<JSObject*> buffer(aCx, aPullIntoDescriptor->Buffer());
+ ReadableByteStreamControllerEnqueueClonedChunkToQueue(
+ aCx, aController, buffer, aPullIntoDescriptor->ByteOffset(),
+ aPullIntoDescriptor->BytesFilled(), aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+
+ // Step 3. Perform !
+ // ReadableByteStreamControllerShiftPendingPullInto(controller).
+ RefPtr<PullIntoDescriptor> discarded =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+ (void)discarded;
+}
+
+// https://streams.spec.whatwg.org/#readable-stream-get-num-read-into-requests
+static size_t ReadableStreamGetNumReadIntoRequests(ReadableStream* aStream) {
+ // Step 1.
+ MOZ_ASSERT(ReadableStreamHasBYOBReader(aStream));
+
+ // Step 2.
+ return aStream->GetReader()->AsBYOB()->ReadIntoRequests().length();
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-should-call-pull
+bool ReadableByteStreamControllerShouldCallPull(
+ ReadableByteStreamController* aController) {
+ // Step 1. Let stream be controller.[[stream]].
+ ReadableStream* stream = aController->Stream();
+
+ // Step 2. If stream.[[state]] is not "readable", return false.
+ if (stream->State() != ReadableStream::ReaderState::Readable) {
+ return false;
+ }
+
+ // Step 3. If controller.[[closeRequested]] is true, return false.
+ if (aController->CloseRequested()) {
+ return false;
+ }
+
+ // Step 4. If controller.[[started]] is false, return false.
+ if (!aController->Started()) {
+ return false;
+ }
+
+ // Step 5. If ! ReadableStreamHasDefaultReader(stream) is true
+ // and ! ReadableStreamGetNumReadRequests(stream) > 0, return true.
+ if (ReadableStreamHasDefaultReader(stream) &&
+ ReadableStreamGetNumReadRequests(stream) > 0) {
+ return true;
+ }
+
+ // Step 6. If ! ReadableStreamHasBYOBReader(stream) is true
+ // and ! ReadableStreamGetNumReadIntoRequests(stream) > 0, return true.
+ if (ReadableStreamHasBYOBReader(stream) &&
+ ReadableStreamGetNumReadIntoRequests(stream) > 0) {
+ return true;
+ }
+
+ // Step 7. Let desiredSize be
+ // ! ReadableByteStreamControllerGetDesiredSize(controller).
+ Nullable<double> desiredSize =
+ ReadableByteStreamControllerGetDesiredSize(aController);
+
+ // Step 8. Assert: desiredSize is not null.
+ MOZ_ASSERT(!desiredSize.IsNull());
+
+ // Step 9. If desiredSize > 0, return true.
+ // Step 10. Return false.
+ return desiredSize.Value() > 0;
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-call-pull-if-needed
+void ReadableByteStreamControllerCallPullIfNeeded(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1.
+ bool shouldPull = ReadableByteStreamControllerShouldCallPull(aController);
+
+ // Step 2.
+ if (!shouldPull) {
+ return;
+ }
+
+ // Step 3.
+ if (aController->Pulling()) {
+ aController->SetPullAgain(true);
+ return;
+ }
+
+ // Step 4.
+ MOZ_ASSERT(!aController->PullAgain());
+
+ // Step 5.
+ aController->SetPulling(true);
+
+ // Step 6.
+ RefPtr<ReadableStreamController> controller(aController);
+ RefPtr<UnderlyingSourceAlgorithmsBase> algorithms =
+ aController->GetAlgorithms();
+ RefPtr<Promise> pullPromise = algorithms->PullCallback(aCx, *controller, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Steps 7+8
+ pullPromise->AddCallbacksWithCycleCollectedArgs(
+ [](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
+ ReadableByteStreamController* aController)
+ MOZ_CAN_RUN_SCRIPT_BOUNDARY {
+ // Step 7.1
+ aController->SetPulling(false);
+ // Step 7.2
+ if (aController->PullAgain()) {
+ // Step 7.2.1
+ aController->SetPullAgain(false);
+
+ // Step 7.2.2
+ ReadableByteStreamControllerCallPullIfNeeded(
+ aCx, MOZ_KnownLive(aController), aRv);
+ }
+ },
+ [](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
+ ReadableByteStreamController* aController) {
+ // Step 8.1
+ ReadableByteStreamControllerError(aController, aValue, aRv);
+ },
+ RefPtr(aController));
+}
+
+bool ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ PullIntoDescriptor* aPullIntoDescriptor, ErrorResult& aRv);
+
+JSObject* ReadableByteStreamControllerConvertPullIntoDescriptor(
+ JSContext* aCx, PullIntoDescriptor* pullIntoDescriptor, ErrorResult& aRv);
+
+// https://streams.spec.whatwg.org/#readable-stream-fulfill-read-into-request
+MOZ_CAN_RUN_SCRIPT
+void ReadableStreamFulfillReadIntoRequest(JSContext* aCx,
+ ReadableStream* aStream,
+ JS::Handle<JS::Value> aChunk,
+ bool done, ErrorResult& aRv) {
+ // Step 1. Assert: !ReadableStreamHasBYOBReader(stream) is true.
+ MOZ_ASSERT(ReadableStreamHasBYOBReader(aStream));
+
+ // Step 2. Let reader be stream.[[reader]].
+ ReadableStreamBYOBReader* reader = aStream->GetReader()->AsBYOB();
+
+ // Step 3. Assert: reader.[[readIntoRequests]] is not empty.
+ MOZ_ASSERT(!reader->ReadIntoRequests().isEmpty());
+
+ // Step 4. Let readIntoRequest be reader.[[readIntoRequests]][0].
+ // Step 5. Remove readIntoRequest from reader.[[readIntoRequests]].
+ RefPtr<ReadIntoRequest> readIntoRequest =
+ reader->ReadIntoRequests().popFirst();
+
+ // Step 6. If done is true, perform readIntoRequest’s close steps, given
+ // chunk.
+ if (done) {
+ readIntoRequest->CloseSteps(aCx, aChunk, aRv);
+ return;
+ }
+
+ // Step 7. Otherwise, perform readIntoRequest’s chunk steps, given chunk.
+ readIntoRequest->ChunkSteps(aCx, aChunk, aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-commit-pull-into-descriptor
+MOZ_CAN_RUN_SCRIPT
+void ReadableByteStreamControllerCommitPullIntoDescriptor(
+ JSContext* aCx, ReadableStream* aStream,
+ PullIntoDescriptor* pullIntoDescriptor, ErrorResult& aRv) {
+ // Step 1. Assert: stream.[[state]] is not "errored".
+ MOZ_ASSERT(aStream->State() != ReadableStream::ReaderState::Errored);
+
+ // Step 2. Assert: pullIntoDescriptor.reader type is not "none".
+ MOZ_ASSERT(pullIntoDescriptor->GetReaderType() != ReaderType::None);
+
+ // Step 3. Let done be false.
+ bool done = false;
+
+ // Step 4. If stream.[[state]] is "closed",
+ if (aStream->State() == ReadableStream::ReaderState::Closed) {
+ // Step 4.1. Assert: pullIntoDescriptor’s bytes filled is 0.
+ MOZ_ASSERT(pullIntoDescriptor->BytesFilled() == 0);
+
+ // Step 4.2. Set done to true.
+ done = true;
+ }
+
+ // Step 5. Let filledView be !
+ // ReadableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor).
+ JS::Rooted<JSObject*> filledView(
+ aCx, ReadableByteStreamControllerConvertPullIntoDescriptor(
+ aCx, pullIntoDescriptor, aRv));
+ if (aRv.Failed()) {
+ return;
+ }
+ JS::Rooted<JS::Value> filledViewValue(aCx, JS::ObjectValue(*filledView));
+
+ // Step 6. If pullIntoDescriptor’s reader type is "default",
+ if (pullIntoDescriptor->GetReaderType() == ReaderType::Default) {
+ // Step 6.1. Perform !ReadableStreamFulfillReadRequest(stream, filledView,
+ // done).
+ ReadableStreamFulfillReadRequest(aCx, aStream, filledViewValue, done, aRv);
+ return;
+ }
+
+ // Step 7.1. Assert: pullIntoDescriptor’s reader type is "byob".
+ MOZ_ASSERT(pullIntoDescriptor->GetReaderType() == ReaderType::BYOB);
+
+ // Step 7.2 Perform !ReadableStreamFulfillReadIntoRequest(stream, filledView,
+ // done).
+ ReadableStreamFulfillReadIntoRequest(aCx, aStream, filledViewValue, done,
+ aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-process-pull-into-descriptors-using-queue
+MOZ_CAN_RUN_SCRIPT
+void ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1. Assert: controller.[[closeRequested]] is false.
+ MOZ_ASSERT(!aController->CloseRequested());
+
+ // Step 2. While controller.[[pendingPullIntos]] is not empty,
+ while (!aController->PendingPullIntos().isEmpty()) {
+ // Step 2.1 If controller.[[queueTotalSize]] is 0, return.
+ if (aController->QueueTotalSize() == 0) {
+ return;
+ }
+
+ // Step 2.2. Let pullIntoDescriptor be controller.[[pendingPullIntos]][0].
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 2.3. If
+ // !ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller,
+ // pullIntoDescriptor) is true,
+ bool ready = ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(
+ aCx, aController, pullIntoDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ if (ready) {
+ // Step 2.3.1. Perform
+ // !ReadableByteStreamControllerShiftPendingPullInto(controller).
+ RefPtr<PullIntoDescriptor> discardedPullIntoDescriptor =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+
+ // Step 2.3.2. Perform
+ // !ReadableByteStreamControllerCommitPullIntoDescriptor(controller.[[stream]],
+ // pullIntoDescriptor).
+ RefPtr<ReadableStream> stream(aController->Stream());
+ ReadableByteStreamControllerCommitPullIntoDescriptor(
+ aCx, stream, pullIntoDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+ }
+}
+
+MOZ_CAN_RUN_SCRIPT
+void ReadableByteStreamControllerHandleQueueDrain(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv);
+
+// https://streams.spec.whatwg.org/#abstract-opdef-readablebytestreamcontrollerfillreadrequestfromqueue
+MOZ_CAN_RUN_SCRIPT void ReadableByteStreamControllerFillReadRequestFromQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ReadRequest* aReadRequest, ErrorResult& aRv) {
+ // Step 1. Assert: controller.[[queueTotalSize]] > 0.
+ MOZ_ASSERT(aController->QueueTotalSize() > 0);
+ // Also assert that the queue has a non-zero length;
+ MOZ_ASSERT(aController->Queue().length() > 0);
+
+ // Step 2. Let entry be controller.[[queue]][0].
+ // Step 3. Remove entry from controller.[[queue]].
+ RefPtr<ReadableByteStreamQueueEntry> entry = aController->Queue().popFirst();
+
+ // Assert that we actually got an entry.
+ MOZ_ASSERT(entry);
+
+ // Step 4. Set controller.[[queueTotalSize]] to controller.[[queueTotalSize]]
+ // − entry’s byte length.
+ aController->SetQueueTotalSize(aController->QueueTotalSize() -
+ double(entry->ByteLength()));
+
+ // Step 5. Perform ! ReadableByteStreamControllerHandleQueueDrain(controller).
+ ReadableByteStreamControllerHandleQueueDrain(aCx, aController, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 6. Let view be ! Construct(%Uint8Array%, « entry’s buffer, entry’s
+ // byte offset, entry’s byte length »).
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> buffer(aCx, entry->Buffer());
+ JS::Rooted<JSObject*> view(
+ aCx, JS_NewUint8ArrayWithBuffer(aCx, buffer, entry->ByteOffset(),
+ int64_t(entry->ByteLength())));
+ if (!view) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // Step 7. Perform readRequest’s chunk steps, given view.
+ JS::Rooted<JS::Value> viewValue(aCx, JS::ObjectValue(*view));
+ aReadRequest->ChunkSteps(aCx, viewValue, aRv);
+}
+
+MOZ_CAN_RUN_SCRIPT void
+ReadableByteStreamControllerProcessReadRequestsUsingQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1. Let reader be controller.[[stream]].[[reader]].
+ // Step 2. Assert: reader implements ReadableStreamDefaultReader.
+ RefPtr<ReadableStreamDefaultReader> reader =
+ aController->Stream()->GetDefaultReader();
+
+ // Step 3. While reader.[[readRequests]] is not empty,
+ while (!reader->ReadRequests().isEmpty()) {
+ // Step 3.1. If controller.[[queueTotalSize]] is 0, return.
+ if (aController->QueueTotalSize() == 0) {
+ return;
+ }
+
+ // Step 3.2. Let readRequest be reader.[[readRequests]][0].
+ // Step 3.3. Remove readRequest from reader.[[readRequests]].
+ RefPtr<ReadRequest> readRequest = reader->ReadRequests().popFirst();
+
+ // Step 3.4. Perform !
+ // ReadableByteStreamControllerFillReadRequestFromQueue(controller,
+ // readRequest).
+ ReadableByteStreamControllerFillReadRequestFromQueue(aCx, aController,
+ readRequest, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-enqueue
+void ReadableByteStreamControllerEnqueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ JS::Handle<JSObject*> aChunk, ErrorResult& aRv) {
+ aRv.MightThrowJSException();
+
+ // Step 1.
+ RefPtr<ReadableStream> stream = aController->Stream();
+
+ // Step 2.
+ if (aController->CloseRequested() ||
+ stream->State() != ReadableStream::ReaderState::Readable) {
+ return;
+ }
+
+ // Step 3.
+ bool isShared;
+ JS::Rooted<JSObject*> buffer(
+ aCx, JS_GetArrayBufferViewBuffer(aCx, aChunk, &isShared));
+ if (!buffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // Step 4.
+ size_t byteOffset = JS_GetArrayBufferViewByteOffset(aChunk);
+
+ // Step 5.
+ size_t byteLength = JS_GetArrayBufferViewByteLength(aChunk);
+
+ // Step 6.
+ if (JS::IsDetachedArrayBufferObject(buffer)) {
+ aRv.ThrowTypeError("Detached Array Buffer");
+ return;
+ }
+
+ // Step 7.
+ JS::Rooted<JSObject*> transferredBuffer(aCx,
+ TransferArrayBuffer(aCx, buffer));
+ if (!transferredBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // Step 8.
+ if (!aController->PendingPullIntos().isEmpty()) {
+ // Step 8.1
+ RefPtr<PullIntoDescriptor> firstPendingPullInto =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 8.2
+ JS::Rooted<JSObject*> pendingBuffer(aCx, firstPendingPullInto->Buffer());
+ if (JS::IsDetachedArrayBufferObject(pendingBuffer)) {
+ aRv.ThrowTypeError("Pending PullInto has detached buffer");
+ return;
+ }
+
+ // Step 8.3. Perform !
+ // ReadableByteStreamControllerInvalidateBYOBRequest(controller).
+ ReadableByteStreamControllerInvalidateBYOBRequest(aController);
+
+ // Step 8.4. Set firstPendingPullInto’s buffer to !
+ // TransferArrayBuffer(firstPendingPullInto’s buffer).
+ pendingBuffer = TransferArrayBuffer(aCx, pendingBuffer);
+ if (!pendingBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ firstPendingPullInto->SetBuffer(pendingBuffer);
+
+ // Step 8.5. If firstPendingPullInto’s reader type is "none", perform ?
+ // ReadableByteStreamControllerEnqueueDetachedPullIntoToQueue(controller,
+ // firstPendingPullInto).
+ if (firstPendingPullInto->GetReaderType() == ReaderType::None) {
+ ReadableByteStreamControllerEnqueueDetachedPullIntoToQueue(
+ aCx, aController, firstPendingPullInto, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+ }
+
+ // Step 9. If ! ReadableStreamHasDefaultReader(stream) is true,
+ if (ReadableStreamHasDefaultReader(stream)) {
+ // Step 9.1. Perform !
+ // ReadableByteStreamControllerProcessReadRequestsUsingQueue(controller).
+ ReadableByteStreamControllerProcessReadRequestsUsingQueue(aCx, aController,
+ aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 9.2. If ! ReadableStreamGetNumReadRequests(stream) is 0,
+ if (ReadableStreamGetNumReadRequests(stream) == 0) {
+ // Step 9.2.1 Assert: controller.[[pendingPullIntos]] is empty.
+ MOZ_ASSERT(aController->PendingPullIntos().isEmpty());
+
+ // Step 9.2.2. Perform !
+ // ReadableByteStreamControllerEnqueueChunkToQueue(controller,
+ // transferredBuffer, byteOffset, byteLength).
+ ReadableByteStreamControllerEnqueueChunkToQueue(
+ aController, transferredBuffer, byteOffset, byteLength);
+
+ // Step 9.3. Otherwise,
+ } else {
+ // Step 9.3.1 Assert: controller.[[queue]] is empty.
+ MOZ_ASSERT(aController->Queue().isEmpty());
+
+ // Step 9.3.2. If controller.[[pendingPullIntos]] is not empty,
+ if (!aController->PendingPullIntos().isEmpty()) {
+ // Step 9.3.2.1. Assert: controller.[[pendingPullIntos]][0]'s reader
+ // type is "default".
+ MOZ_ASSERT(
+ aController->PendingPullIntos().getFirst()->GetReaderType() ==
+ ReaderType::Default);
+
+ // Step 9.3.2.2. Perform !
+ // ReadableByteStreamControllerShiftPendingPullInto(controller).
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+ (void)pullIntoDescriptor;
+ }
+
+ // Step 9.3.3. Let transferredView be ! Construct(%Uint8Array%, «
+ // transferredBuffer, byteOffset, byteLength »).
+ JS::Rooted<JSObject*> transferredView(
+ aCx, JS_NewUint8ArrayWithBuffer(aCx, transferredBuffer, byteOffset,
+ int64_t(byteLength)));
+ if (!transferredView) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // Step 9.3.4. Perform ! ReadableStreamFulfillReadRequest(stream,
+ // transferredView, false).
+ JS::Rooted<JS::Value> transferredViewValue(
+ aCx, JS::ObjectValue(*transferredView));
+ ReadableStreamFulfillReadRequest(aCx, stream, transferredViewValue, false,
+ aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+
+ // Step 10. Otherwise, if ! ReadableStreamHasBYOBReader(stream) is true,
+ } else if (ReadableStreamHasBYOBReader(stream)) {
+ // Step 10.1. Perform !
+ // ReadableByteStreamControllerEnqueueChunkToQueue(controller,
+ // transferredBuffer, byteOffset, byteLength).
+ ReadableByteStreamControllerEnqueueChunkToQueue(
+ aController, transferredBuffer, byteOffset, byteLength);
+
+ // Step 10.2 Perform !
+ // ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller).
+ ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(
+ aCx, aController, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 11. Otherwise,
+ } else {
+ // Step 11.1. Assert: ! IsReadableStreamLocked(stream) is false.
+ MOZ_ASSERT(!IsReadableStreamLocked(stream));
+
+ // Step 11.2. Perform !
+ // ReadableByteStreamControllerEnqueueChunkToQueue(controller,
+ // transferredBuffer, byteOffset, byteLength).
+ ReadableByteStreamControllerEnqueueChunkToQueue(
+ aController, transferredBuffer, byteOffset, byteLength);
+ }
+
+ // Step 12. Perform !
+ // ReadableByteStreamControllerCallPullIfNeeded(controller).
+ ReadableByteStreamControllerCallPullIfNeeded(aCx, aController, aRv);
+}
+
+} // namespace streams_abstract
+
+// https://streams.spec.whatwg.org/#rbs-controller-enqueue
+void ReadableByteStreamController::Enqueue(JSContext* aCx,
+ const ArrayBufferView& aChunk,
+ ErrorResult& aRv) {
+ // Step 1.
+ JS::Rooted<JSObject*> chunk(aCx, aChunk.Obj());
+ if (JS_GetArrayBufferViewByteLength(chunk) == 0) {
+ aRv.ThrowTypeError("Zero Length View");
+ return;
+ }
+
+ // Step 2.
+ bool isShared;
+ JS::Rooted<JSObject*> viewedArrayBuffer(
+ aCx, JS_GetArrayBufferViewBuffer(aCx, chunk, &isShared));
+ if (!viewedArrayBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ if (JS::GetArrayBufferByteLength(viewedArrayBuffer) == 0) {
+ aRv.ThrowTypeError("Zero Length Buffer");
+ return;
+ }
+
+ // Step 3.
+ if (CloseRequested()) {
+ aRv.ThrowTypeError("close requested");
+ return;
+ }
+
+ // Step 4.
+ if (Stream()->State() != ReadableStream::ReaderState::Readable) {
+ aRv.ThrowTypeError("Not Readable");
+ return;
+ }
+
+ // Step 5.
+ ReadableByteStreamControllerEnqueue(aCx, this, chunk, aRv);
+}
+
+// https://streams.spec.whatwg.org/#rbs-controller-error
+void ReadableByteStreamController::Error(JSContext* aCx,
+ JS::Handle<JS::Value> aErrorValue,
+ ErrorResult& aRv) {
+ // Step 1.
+ ReadableByteStreamControllerError(this, aErrorValue, aRv);
+}
+
+// https://streams.spec.whatwg.org/#rbs-controller-private-cancel
+already_AddRefed<Promise> ReadableByteStreamController::CancelSteps(
+ JSContext* aCx, JS::Handle<JS::Value> aReason, ErrorResult& aRv) {
+ // Step 1.
+ ReadableByteStreamControllerClearPendingPullIntos(this);
+
+ // Step 2.
+ ResetQueue(this);
+
+ // Step 3.
+ Optional<JS::Handle<JS::Value>> reason(aCx, aReason);
+ RefPtr<UnderlyingSourceAlgorithmsBase> algorithms = mAlgorithms;
+ RefPtr<Promise> result = algorithms->CancelCallback(aCx, reason, aRv);
+ if (NS_WARN_IF(aRv.Failed())) {
+ return nullptr;
+ }
+ // Step 4.
+ ReadableByteStreamControllerClearAlgorithms(this);
+
+ // Step 5.
+ return result.forget();
+}
+
+namespace streams_abstract {
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-handle-queue-drain
+void ReadableByteStreamControllerHandleQueueDrain(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ ErrorResult& aRv) {
+ // Step 1.
+ MOZ_ASSERT(aController->Stream()->State() ==
+ ReadableStream::ReaderState::Readable);
+
+ // Step 2.
+ if (aController->QueueTotalSize() == 0 && aController->CloseRequested()) {
+ // Step 2.1
+ ReadableByteStreamControllerClearAlgorithms(aController);
+
+ // Step 2.2
+ RefPtr<ReadableStream> stream = aController->Stream();
+ ReadableStreamClose(aCx, stream, aRv);
+ return;
+ }
+
+ // Step 3.1
+ ReadableByteStreamControllerCallPullIfNeeded(aCx, aController, aRv);
+}
+} // namespace streams_abstract
+
+// https://streams.spec.whatwg.org/#rbs-controller-private-pull
+void ReadableByteStreamController::PullSteps(JSContext* aCx,
+ ReadRequest* aReadRequest,
+ ErrorResult& aRv) {
+ // Step 1.
+ ReadableStream* stream = Stream();
+
+ // Step 2.
+ MOZ_ASSERT(ReadableStreamHasDefaultReader(stream));
+
+ // Step 3.
+ if (QueueTotalSize() > 0) {
+ // Step 3.1. Assert: ! ReadableStreamGetNumReadRequests ( stream ) is 0.
+ MOZ_ASSERT(ReadableStreamGetNumReadRequests(stream) == 0);
+
+ // Step 3.2. Perform !
+ // ReadableByteStreamControllerFillReadRequestFromQueue(this, readRequest).
+ ReadableByteStreamControllerFillReadRequestFromQueue(aCx, this,
+ aReadRequest, aRv);
+
+ // Step 3.3. Return.
+ return;
+ }
+
+ // Step 4.
+ Maybe<uint64_t> autoAllocateChunkSize = AutoAllocateChunkSize();
+
+ // Step 5.
+ if (autoAllocateChunkSize) {
+ // Step 5.1
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> buffer(
+ aCx, JS::NewArrayBuffer(aCx, *autoAllocateChunkSize));
+ // Step 5.2
+ if (!buffer) {
+ // Step 5.2.1
+ JS::Rooted<JS::Value> bufferError(aCx);
+ if (!JS_GetPendingException(aCx, &bufferError)) {
+ // Uncatchable exception; we should mark aRv and return.
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // It's not expliclitly stated, but I assume the intention here is that
+ // we perform a normal completion here.
+ JS_ClearPendingException(aCx);
+
+ aReadRequest->ErrorSteps(aCx, bufferError, aRv);
+
+ // Step 5.2.2.
+ return;
+ }
+
+ // Step 5.3
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor = new PullIntoDescriptor(
+ buffer, *autoAllocateChunkSize, 0, *autoAllocateChunkSize, 0, 1,
+ PullIntoDescriptor::Constructor::Uint8, ReaderType::Default);
+
+ // Step 5.4
+ PendingPullIntos().insertBack(pullIntoDescriptor);
+ }
+
+ // Step 6.
+ ReadableStreamAddReadRequest(stream, aReadRequest);
+
+ // Step 7.
+ ReadableByteStreamControllerCallPullIfNeeded(aCx, this, aRv);
+}
+
+// https://streams.spec.whatwg.org/#abstract-opdef-readablebytestreamcontroller-releasesteps
+void ReadableByteStreamController::ReleaseSteps() {
+ // Step 1. If this.[[pendingPullIntos]] is not empty,
+ if (!PendingPullIntos().isEmpty()) {
+ // Step 1.1. Let firstPendingPullInto be this.[[pendingPullIntos]][0].
+ RefPtr<PullIntoDescriptor> firstPendingPullInto =
+ PendingPullIntos().popFirst();
+
+ // Step 1.2. Set firstPendingPullInto’s reader type to "none".
+ firstPendingPullInto->SetReaderType(ReaderType::None);
+
+ // Step 1.3. Set this.[[pendingPullIntos]] to the list «
+ // firstPendingPullInto ».
+ PendingPullIntos().clear();
+ PendingPullIntos().insertBack(firstPendingPullInto);
+ }
+}
+
+namespace streams_abstract {
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-shift-pending-pull-into
+already_AddRefed<PullIntoDescriptor>
+ReadableByteStreamControllerShiftPendingPullInto(
+ ReadableByteStreamController* aController) {
+ // Step 1.
+ MOZ_ASSERT(!aController->GetByobRequest());
+
+ // Step 2 + 3
+ RefPtr<PullIntoDescriptor> descriptor =
+ aController->PendingPullIntos().popFirst();
+
+ // Step 4.
+ return descriptor.forget();
+}
+
+JSObject* ConstructFromPullIntoConstructor(
+ JSContext* aCx, PullIntoDescriptor::Constructor constructor,
+ JS::Handle<JSObject*> buffer, size_t byteOffset, size_t length) {
+ switch (constructor) {
+ case PullIntoDescriptor::Constructor::DataView:
+ return JS_NewDataView(aCx, buffer, byteOffset, length);
+ break;
+
+#define CONSTRUCT_TYPED_ARRAY_TYPE(ExternalT, NativeT, Name) \
+ case PullIntoDescriptor::Constructor::Name: \
+ return JS_New##Name##ArrayWithBuffer(aCx, buffer, byteOffset, \
+ int64_t(length)); \
+ break;
+
+ JS_FOR_EACH_TYPED_ARRAY(CONSTRUCT_TYPED_ARRAY_TYPE)
+
+#undef CONSTRUCT_TYPED_ARRAY_TYPE
+
+ default:
+ MOZ_ASSERT_UNREACHABLE("Unknown PullIntoDescriptor::Constructor");
+ return nullptr;
+ }
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-convert-pull-into-descriptor
+JSObject* ReadableByteStreamControllerConvertPullIntoDescriptor(
+ JSContext* aCx, PullIntoDescriptor* pullIntoDescriptor, ErrorResult& aRv) {
+ // Step 1. Let bytesFilled be pullIntoDescriptor’s bytes filled.
+ uint64_t bytesFilled = pullIntoDescriptor->BytesFilled();
+
+ // Step 2. Let elementSize be pullIntoDescriptor’s element size.
+ uint64_t elementSize = pullIntoDescriptor->ElementSize();
+
+ // Step 3. Assert: bytesFilled ≤ pullIntoDescriptor’s byte length.
+ MOZ_ASSERT(bytesFilled <= pullIntoDescriptor->ByteLength());
+
+ // Step 4. Assert: bytesFilled mod elementSize is 0.
+ MOZ_ASSERT(bytesFilled % elementSize == 0);
+
+ // Step 5. Let buffer be ! TransferArrayBuffer(pullIntoDescriptor’s buffer).
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> srcBuffer(aCx, pullIntoDescriptor->Buffer());
+ JS::Rooted<JSObject*> buffer(aCx, TransferArrayBuffer(aCx, srcBuffer));
+ if (!buffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return nullptr;
+ }
+
+ // Step 6. Return ! Construct(pullIntoDescriptor’s view constructor,
+ // « buffer, pullIntoDescriptor’s byte offset, bytesFilled ÷ elementSize »).
+ JS::Rooted<JSObject*> res(
+ aCx, ConstructFromPullIntoConstructor(
+ aCx, pullIntoDescriptor->ViewConstructor(), buffer,
+ pullIntoDescriptor->ByteOffset(), bytesFilled / elementSize));
+ if (!res) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return nullptr;
+ }
+ return res;
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-respond-in-closed-state
+MOZ_CAN_RUN_SCRIPT
+static void ReadableByteStreamControllerRespondInClosedState(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ RefPtr<PullIntoDescriptor>& aFirstDescriptor, ErrorResult& aRv) {
+ // Step 1. Assert: firstDescriptor ’s bytes filled is 0.
+ MOZ_ASSERT(aFirstDescriptor->BytesFilled() == 0);
+
+ // Step 2. If firstDescriptor’s reader type is "none",
+ // perform ! ReadableByteStreamControllerShiftPendingPullInto(controller).
+ if (aFirstDescriptor->GetReaderType() == ReaderType::None) {
+ RefPtr<PullIntoDescriptor> discarded =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+ (void)discarded;
+ }
+
+ // Step 3. Let stream be controller.[[stream]].
+ RefPtr<ReadableStream> stream = aController->Stream();
+
+ // Step 4. If ! ReadableStreamHasBYOBReader(stream) is true,
+ if (ReadableStreamHasBYOBReader(stream)) {
+ // Step 4.1. While ! ReadableStreamGetNumReadIntoRequests(stream) > 0,
+ while (ReadableStreamGetNumReadIntoRequests(stream) > 0) {
+ // Step 4.1.1. Let pullIntoDescriptor be !
+ // ReadableByteStreamControllerShiftPendingPullInto(controller).
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+
+ // Step 4.1.2. Perform !
+ // ReadableByteStreamControllerCommitPullIntoDescriptor(stream,
+ // pullIntoDescriptor).
+ ReadableByteStreamControllerCommitPullIntoDescriptor(
+ aCx, stream, pullIntoDescriptor, aRv);
+ }
+ }
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-fill-head-pull-into-descriptor
+void ReadableByteStreamControllerFillHeadPullIntoDescriptor(
+ ReadableByteStreamController* aController, size_t aSize,
+ PullIntoDescriptor* aPullIntoDescriptor) {
+ // Step 1. Assert: either controller.[[pendingPullIntos]] is empty, or
+ // controller.[[pendingPullIntos]][0] is pullIntoDescriptor.
+ MOZ_ASSERT(aController->PendingPullIntos().isEmpty() ||
+ aController->PendingPullIntos().getFirst() == aPullIntoDescriptor);
+
+ // Step 2. Assert: controller.[[byobRequest]] is null.
+ MOZ_ASSERT(!aController->GetByobRequest());
+
+ // Step 3. Set pullIntoDescriptor’s bytes filled to bytes filled + size.
+ aPullIntoDescriptor->SetBytesFilled(aPullIntoDescriptor->BytesFilled() +
+ aSize);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-respond-in-readable-state
+MOZ_CAN_RUN_SCRIPT
+static void ReadableByteStreamControllerRespondInReadableState(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ uint64_t aBytesWritten, PullIntoDescriptor* aPullIntoDescriptor,
+ ErrorResult& aRv) {
+ // Step 1. Assert: pullIntoDescriptor’s bytes filled + bytesWritten ≤
+ // pullIntoDescriptor’s byte length.
+ MOZ_ASSERT(aPullIntoDescriptor->BytesFilled() + aBytesWritten <=
+ aPullIntoDescriptor->ByteLength());
+
+ // Step 2. Perform
+ // !ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller,
+ // bytesWritten, pullIntoDescriptor).
+ ReadableByteStreamControllerFillHeadPullIntoDescriptor(
+ aController, aBytesWritten, aPullIntoDescriptor);
+
+ // Step 3. If pullIntoDescriptor’s reader type is "none",
+ if (aPullIntoDescriptor->GetReaderType() == ReaderType::None) {
+ // Step 3.1. Perform ?
+ // ReadableByteStreamControllerEnqueueDetachedPullIntoToQueue(controller,
+ // pullIntoDescriptor).
+ ReadableByteStreamControllerEnqueueDetachedPullIntoToQueue(
+ aCx, aController, aPullIntoDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 3.2. Perform !
+ // ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller).
+ ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(
+ aCx, aController, aRv);
+
+ // Step 3.3. Return.
+ return;
+ }
+
+ // Step 4. If pullIntoDescriptor’s bytes filled < pullIntoDescriptor’s element
+ // size, return.
+ if (aPullIntoDescriptor->BytesFilled() < aPullIntoDescriptor->ElementSize()) {
+ return;
+ }
+
+ // Step 5. Perform
+ // !ReadableByteStreamControllerShiftPendingPullInto(controller).
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor =
+ ReadableByteStreamControllerShiftPendingPullInto(aController);
+ (void)pullIntoDescriptor;
+
+ // Step 6. Let remainderSize be pullIntoDescriptor’s bytes filled mod
+ // pullIntoDescriptor’s element size.
+ size_t remainderSize =
+ aPullIntoDescriptor->BytesFilled() % aPullIntoDescriptor->ElementSize();
+
+ // Step 7. If remainderSize > 0,
+ if (remainderSize > 0) {
+ // Step 7.1. Let end be pullIntoDescriptor’s byte offset +
+ // pullIntoDescriptor’s bytes filled.
+ size_t end =
+ aPullIntoDescriptor->ByteOffset() + aPullIntoDescriptor->BytesFilled();
+
+ // Step 7.2. Perform ?
+ // ReadableByteStreamControllerEnqueueClonedChunkToQueue(controller,
+ // pullIntoDescriptor’s buffer, end − remainderSize, remainderSize).
+ JS::Rooted<JSObject*> pullIntoBuffer(aCx, aPullIntoDescriptor->Buffer());
+ ReadableByteStreamControllerEnqueueClonedChunkToQueue(
+ aCx, aController, pullIntoBuffer, end - remainderSize, remainderSize,
+ aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+
+ // Step 8. Set pullIntoDescriptor’s bytes filled to pullIntoDescriptor’s bytes
+ // filled − remainderSize.
+ aPullIntoDescriptor->SetBytesFilled(aPullIntoDescriptor->BytesFilled() -
+ remainderSize);
+
+ // Step 9. Perform
+ // !ReadableByteStreamControllerCommitPullIntoDescriptor(controller.[[stream]],
+ // pullIntoDescriptor).
+ RefPtr<ReadableStream> stream(aController->Stream());
+ ReadableByteStreamControllerCommitPullIntoDescriptor(
+ aCx, stream, aPullIntoDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 10. Perform
+ // !ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(controller).
+ ReadableByteStreamControllerProcessPullIntoDescriptorsUsingQueue(
+ aCx, aController, aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-respond-internal
+void ReadableByteStreamControllerRespondInternal(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ uint64_t aBytesWritten, ErrorResult& aRv) {
+ // Step 1.
+ RefPtr<PullIntoDescriptor> firstDescriptor =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 2.
+ JS::Rooted<JSObject*> buffer(aCx, firstDescriptor->Buffer());
+#ifdef DEBUG
+ bool canTransferBuffer = CanTransferArrayBuffer(aCx, buffer, aRv);
+ MOZ_ASSERT(!aRv.Failed());
+ MOZ_ASSERT(canTransferBuffer);
+#endif
+
+ // Step 3.
+ ReadableByteStreamControllerInvalidateBYOBRequest(aController);
+
+ // Step 4.
+ auto state = aController->Stream()->State();
+
+ // Step 5.
+ if (state == ReadableStream::ReaderState::Closed) {
+ // Step 5.1
+ MOZ_ASSERT(aBytesWritten == 0);
+
+ // Step 5.2
+ ReadableByteStreamControllerRespondInClosedState(aCx, aController,
+ firstDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ } else {
+ // Step 6.1
+ MOZ_ASSERT(state == ReadableStream::ReaderState::Readable);
+
+ // Step 6.2.
+ MOZ_ASSERT(aBytesWritten > 0);
+
+ // Step 6.3
+ ReadableByteStreamControllerRespondInReadableState(
+ aCx, aController, aBytesWritten, firstDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ }
+ // Step 7.
+ ReadableByteStreamControllerCallPullIfNeeded(aCx, aController, aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-respond
+void ReadableByteStreamControllerRespond(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ uint64_t aBytesWritten, ErrorResult& aRv) {
+ // Step 1.
+ MOZ_ASSERT(!aController->PendingPullIntos().isEmpty());
+
+ // Step 2.
+ PullIntoDescriptor* firstDescriptor =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 3.
+ auto state = aController->Stream()->State();
+
+ // Step 4.
+ if (state == ReadableStream::ReaderState::Closed) {
+ // Step 4.1
+ if (aBytesWritten != 0) {
+ aRv.ThrowTypeError("bytesWritten not zero on closed stream");
+ return;
+ }
+ } else {
+ // Step 5.1
+ MOZ_ASSERT(state == ReadableStream::ReaderState::Readable);
+
+ // Step 5.2
+ if (aBytesWritten == 0) {
+ aRv.ThrowTypeError("bytesWritten 0");
+ return;
+ }
+
+ // Step 5.3
+ if (firstDescriptor->BytesFilled() + aBytesWritten >
+ firstDescriptor->ByteLength()) {
+ aRv.ThrowRangeError("bytesFilled + bytesWritten > byteLength");
+ return;
+ }
+ }
+
+ // Step 6.
+ aRv.MightThrowJSException();
+ JS::Rooted<JSObject*> buffer(aCx, firstDescriptor->Buffer());
+ JS::Rooted<JSObject*> transferredBuffer(aCx,
+ TransferArrayBuffer(aCx, buffer));
+ if (!transferredBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ firstDescriptor->SetBuffer(transferredBuffer);
+
+ // Step 7.
+ ReadableByteStreamControllerRespondInternal(aCx, aController, aBytesWritten,
+ aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-respond-with-new-view
+void ReadableByteStreamControllerRespondWithNewView(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ JS::Handle<JSObject*> aView, ErrorResult& aRv) {
+ aRv.MightThrowJSException();
+
+ // Step 1.
+ MOZ_ASSERT(!aController->PendingPullIntos().isEmpty());
+
+ // Step 2.
+ bool isSharedMemory;
+ JS::Rooted<JSObject*> viewedArrayBuffer(
+ aCx, JS_GetArrayBufferViewBuffer(aCx, aView, &isSharedMemory));
+ if (!viewedArrayBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ MOZ_ASSERT(!JS::IsDetachedArrayBufferObject(viewedArrayBuffer));
+
+ // Step 3.
+ RefPtr<PullIntoDescriptor> firstDescriptor =
+ aController->PendingPullIntos().getFirst();
+
+ // Step 4.
+ ReadableStream::ReaderState state = aController->Stream()->State();
+
+ // Step 5.
+ if (state == ReadableStream::ReaderState::Closed) {
+ // Step 5.1
+ if (JS_GetArrayBufferViewByteLength(aView) != 0) {
+ aRv.ThrowTypeError("View has non-zero length in closed stream");
+ return;
+ }
+ } else {
+ // Step 6.1
+ MOZ_ASSERT(state == ReadableStream::ReaderState::Readable);
+
+ // Step 6.2
+ if (JS_GetArrayBufferViewByteLength(aView) == 0) {
+ aRv.ThrowTypeError("View has zero length in readable stream");
+ return;
+ }
+ }
+
+ // Step 7.
+ if (firstDescriptor->ByteOffset() + firstDescriptor->BytesFilled() !=
+ JS_GetArrayBufferViewByteOffset(aView)) {
+ aRv.ThrowRangeError("Invalid Offset");
+ return;
+ }
+
+ // Step 8.
+ if (firstDescriptor->BufferByteLength() !=
+ JS::GetArrayBufferByteLength(viewedArrayBuffer)) {
+ aRv.ThrowRangeError("Mismatched buffer byte lengths");
+ return;
+ }
+
+ // Step 9.
+ if (firstDescriptor->BytesFilled() + JS_GetArrayBufferViewByteLength(aView) >
+ firstDescriptor->ByteLength()) {
+ aRv.ThrowRangeError("Too many bytes");
+ return;
+ }
+
+ // Step 10. Let viewByteLength be view.[[ByteLength]].
+ size_t viewByteLength = JS_GetArrayBufferViewByteLength(aView);
+
+ // Step 11. Set firstDescriptor’s buffer to ?
+ // TransferArrayBuffer(view.[[ViewedArrayBuffer]]).
+ JS::Rooted<JSObject*> transferedBuffer(
+ aCx, TransferArrayBuffer(aCx, viewedArrayBuffer));
+ if (!transferedBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ firstDescriptor->SetBuffer(transferedBuffer);
+
+ // Step 12. Perform ? ReadableByteStreamControllerRespondInternal(controller,
+ // viewByteLength).
+ ReadableByteStreamControllerRespondInternal(aCx, aController, viewByteLength,
+ aRv);
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-fill-pull-into-descriptor-from-queue
+bool ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ PullIntoDescriptor* aPullIntoDescriptor, ErrorResult& aRv) {
+ // Step 1. Let elementSize be pullIntoDescriptor.[[elementSize]].
+ size_t elementSize = aPullIntoDescriptor->ElementSize();
+
+ // Step 2. Let currentAlignedBytes be pullIntoDescriptor’s bytes filled −
+ // (pullIntoDescriptor’s bytes filled mod elementSize).
+ size_t currentAlignedBytes =
+ aPullIntoDescriptor->BytesFilled() -
+ (aPullIntoDescriptor->BytesFilled() % elementSize);
+
+ // Step 3. Let maxBytesToCopy be min(controller.[[queueTotalSize]],
+ // pullIntoDescriptor’s byte length − pullIntoDescriptor’s bytes filled).
+ size_t maxBytesToCopy =
+ std::min(static_cast<size_t>(aController->QueueTotalSize()),
+ static_cast<size_t>((aPullIntoDescriptor->ByteLength() -
+ aPullIntoDescriptor->BytesFilled())));
+
+ // Step 4. Let maxBytesFilled be pullIntoDescriptor’s bytes filled +
+ // maxBytesToCopy.
+ size_t maxBytesFilled = aPullIntoDescriptor->BytesFilled() + maxBytesToCopy;
+
+ // Step 5. Let maxAlignedBytes be maxBytesFilled − (maxBytesFilled mod
+ // elementSize).
+ size_t maxAlignedBytes = maxBytesFilled - (maxBytesFilled % elementSize);
+
+ // Step 6. Let totalBytesToCopyRemaining be maxBytesToCopy.
+ size_t totalBytesToCopyRemaining = maxBytesToCopy;
+
+ // Step 7. Let ready be false.
+ bool ready = false;
+
+ // Step 8. If maxAlignedBytes > currentAlignedBytes,
+ if (maxAlignedBytes > currentAlignedBytes) {
+ // Step 8.1. Set totalBytesToCopyRemaining to maxAlignedBytes −
+ // pullIntoDescriptor’s bytes filled.
+ totalBytesToCopyRemaining =
+ maxAlignedBytes - aPullIntoDescriptor->BytesFilled();
+ // Step 8.2. Set ready to true.
+ ready = true;
+ }
+
+ // Step 9. Let queue be controller.[[queue]].
+ LinkedList<RefPtr<ReadableByteStreamQueueEntry>>& queue =
+ aController->Queue();
+
+ // Step 10. While totalBytesToCopyRemaining > 0,
+ while (totalBytesToCopyRemaining > 0) {
+ // Step 10.1 Let headOfQueue be queue[0].
+ ReadableByteStreamQueueEntry* headOfQueue = queue.getFirst();
+
+ // Step 10.2. Let bytesToCopy be min(totalBytesToCopyRemaining,
+ // headOfQueue’s byte length).
+ size_t bytesToCopy =
+ std::min(totalBytesToCopyRemaining, headOfQueue->ByteLength());
+
+ // Step 10.3. Let destStart be pullIntoDescriptor’s byte offset +
+ // pullIntoDescriptor’s bytes filled.
+ size_t destStart =
+ aPullIntoDescriptor->ByteOffset() + aPullIntoDescriptor->BytesFilled();
+
+ // Step 10.4. Perform !CopyDataBlockBytes(pullIntoDescriptor’s
+ // buffer.[[ArrayBufferData]], destStart, headOfQueue’s
+ // buffer.[[ArrayBufferData]], headOfQueue’s byte offset,
+ // bytesToCopy).
+ JS::Rooted<JSObject*> descriptorBuffer(aCx, aPullIntoDescriptor->Buffer());
+ JS::Rooted<JSObject*> queueBuffer(aCx, headOfQueue->Buffer());
+ if (!JS::ArrayBufferCopyData(aCx, descriptorBuffer, destStart, queueBuffer,
+ headOfQueue->ByteOffset(), bytesToCopy)) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return false;
+ }
+
+ // Step 10.5. If headOfQueue’s byte length is bytesToCopy,
+ if (headOfQueue->ByteLength() == bytesToCopy) {
+ // Step 10.5.1. Remove queue[0].
+ queue.popFirst();
+ } else {
+ // Step 10.6. Otherwise,
+
+ // Step 10.6.1 Set headOfQueue’s byte offset to
+ // headOfQueue’s byte offset + bytesToCopy.
+ headOfQueue->SetByteOffset(headOfQueue->ByteOffset() + bytesToCopy);
+ // Step 10.6.2 Set headOfQueue’s byte length to
+ // headOfQueue’s byte length − bytesToCopy.
+ headOfQueue->SetByteLength(headOfQueue->ByteLength() - bytesToCopy);
+ }
+
+ // Step 10.7. Set controller.[[queueTotalSize]] to
+ // controller.[[queueTotalSize]] − bytesToCopy.
+ aController->SetQueueTotalSize(aController->QueueTotalSize() -
+ (double)bytesToCopy);
+
+ // Step 10.8, Perform
+ // !ReadableByteStreamControllerFillHeadPullIntoDescriptor(controller,
+ // bytesToCopy, pullIntoDescriptor).
+ ReadableByteStreamControllerFillHeadPullIntoDescriptor(
+ aController, bytesToCopy, aPullIntoDescriptor);
+
+ // Step 10.9. Set totalBytesToCopyRemaining to totalBytesToCopyRemaining −
+ // bytesToCopy.
+ totalBytesToCopyRemaining = totalBytesToCopyRemaining - bytesToCopy;
+ }
+
+ // Step 11. If ready is false,
+ if (!ready) {
+ // Step 11.1. Assert: controller.[[queueTotalSize]] is 0.
+ MOZ_ASSERT(aController->QueueTotalSize() == 0);
+
+ // Step 11.2. Assert: pullIntoDescriptor’s bytes filled > 0.
+ MOZ_ASSERT(aPullIntoDescriptor->BytesFilled() > 0);
+
+ // Step 11.3. Assert: pullIntoDescriptor’s bytes filled <
+ // pullIntoDescriptor’s
+ // element size.
+ MOZ_ASSERT(aPullIntoDescriptor->BytesFilled() <
+ aPullIntoDescriptor->ElementSize());
+ }
+
+ // Step 12. Return ready.
+ return ready;
+}
+
+// https://streams.spec.whatwg.org/#readable-byte-stream-controller-pull-into
+void ReadableByteStreamControllerPullInto(
+ JSContext* aCx, ReadableByteStreamController* aController,
+ JS::Handle<JSObject*> aView, ReadIntoRequest* aReadIntoRequest,
+ ErrorResult& aRv) {
+ aRv.MightThrowJSException();
+
+ // Step 1. Let stream be controller.[[stream]].
+ ReadableStream* stream = aController->Stream();
+
+ // Step 2. Let elementSize be 1.
+ size_t elementSize = 1;
+
+ // Step 3. Let ctor be %DataView%.
+ PullIntoDescriptor::Constructor ctor =
+ PullIntoDescriptor::Constructor::DataView;
+
+ // Step 4. If view has a [[TypedArrayName]] internal slot (i.e., it is not a
+ // DataView),
+ if (JS_IsTypedArrayObject(aView)) {
+ // Step 4.1. Set elementSize to the element size specified in the typed
+ // array constructors table for view.[[TypedArrayName]].
+ JS::Scalar::Type type = JS_GetArrayBufferViewType(aView);
+ elementSize = JS::Scalar::byteSize(type);
+
+ // Step 4.2 Set ctor to the constructor specified in the typed array
+ // constructors table for view.[[TypedArrayName]].
+ ctor = PullIntoDescriptor::constructorFromScalar(type);
+ }
+
+ // Step 5. Let byteOffset be view.[[ByteOffset]].
+ size_t byteOffset = JS_GetArrayBufferViewByteOffset(aView);
+
+ // Step 6. Let byteLength be view.[[ByteLength]].
+ size_t byteLength = JS_GetArrayBufferViewByteLength(aView);
+
+ // Step 7. Let bufferResult be
+ // TransferArrayBuffer(view.[[ViewedArrayBuffer]]).
+ bool isShared;
+ JS::Rooted<JSObject*> viewedArrayBuffer(
+ aCx, JS_GetArrayBufferViewBuffer(aCx, aView, &isShared));
+ if (!viewedArrayBuffer) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+ JS::Rooted<JSObject*> bufferResult(
+ aCx, TransferArrayBuffer(aCx, viewedArrayBuffer));
+
+ // Step 8. If bufferResult is an abrupt completion,
+ if (!bufferResult) {
+ JS::Rooted<JS::Value> pendingException(aCx);
+ if (!JS_GetPendingException(aCx, &pendingException)) {
+ // This means an un-catchable exception. Use StealExceptionFromJSContext
+ // to setup aRv properly.
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // It's not expliclitly stated, but I assume the intention here is that
+ // we perform a normal completion here; we also need to clear the
+ // exception state anyhow to succesfully run ErrorSteps.
+ JS_ClearPendingException(aCx);
+
+ // Step 8.1. Perform readIntoRequest’s error steps, given
+ // bufferResult.[[Value]].
+ aReadIntoRequest->ErrorSteps(aCx, pendingException, aRv);
+
+ // Step 8.2. Return.
+ return;
+ }
+
+ // Step 9. Let buffer be bufferResult.[[Value]].
+ JS::Rooted<JSObject*> buffer(aCx, bufferResult);
+
+ // Step 10. Let pullIntoDescriptor be a new pull-into descriptor with
+ // buffer: buffer,
+ // buffer byte length: buffer.[[ArrayBufferByteLength]],
+ // byte offset: byteOffset,
+ // byte length: byteLength,
+ // bytes filled: 0,
+ // element size: elementSize,
+ // view constructor: ctor,
+ // and reader type: "byob".
+ RefPtr<PullIntoDescriptor> pullIntoDescriptor = new PullIntoDescriptor(
+ buffer, JS::GetArrayBufferByteLength(buffer), byteOffset, byteLength, 0,
+ elementSize, ctor, ReaderType::BYOB);
+
+ // Step 11. If controller.[[pendingPullIntos]] is not empty,
+ if (!aController->PendingPullIntos().isEmpty()) {
+ // Step 11.1. Append pullIntoDescriptor to controller.[[pendingPullIntos]].
+ aController->PendingPullIntos().insertBack(pullIntoDescriptor);
+
+ // Step 11.2. Perform !ReadableStreamAddReadIntoRequest(stream,
+ // readIntoRequest).
+ ReadableStreamAddReadIntoRequest(stream, aReadIntoRequest);
+
+ // Step 11.3. Return.
+ return;
+ }
+
+ // Step 12. If stream.[[state]] is "closed",
+ if (stream->State() == ReadableStream::ReaderState::Closed) {
+ // Step 12.1. Let emptyView be !Construct(ctor, « pullIntoDescriptor’s
+ // buffer, pullIntoDescriptor’s byte offset, 0 »).
+ JS::Rooted<JSObject*> pullIntoBuffer(aCx, pullIntoDescriptor->Buffer());
+ JS::Rooted<JSObject*> emptyView(
+ aCx,
+ ConstructFromPullIntoConstructor(aCx, ctor, pullIntoBuffer,
+ pullIntoDescriptor->ByteOffset(), 0));
+ if (!emptyView) {
+ aRv.StealExceptionFromJSContext(aCx);
+ return;
+ }
+
+ // Step 12.2. Perform readIntoRequest’s close steps, given emptyView.
+ JS::Rooted<JS::Value> emptyViewValue(aCx, JS::ObjectValue(*emptyView));
+ aReadIntoRequest->CloseSteps(aCx, emptyViewValue, aRv);
+
+ // Step 12.3. Return.
+ return;
+ }
+
+ // Step 13,. If controller.[[queueTotalSize]] > 0,
+ if (aController->QueueTotalSize() > 0) {
+ // Step 13.1 If
+ // !ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(controller,
+ // pullIntoDescriptor) is true,
+ bool ready = ReadableByteStreamControllerFillPullIntoDescriptorFromQueue(
+ aCx, aController, pullIntoDescriptor, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ if (ready) {
+ // Step 13.1.1 Let filledView be
+ // !ReadableByteStreamControllerConvertPullIntoDescriptor(pullIntoDescriptor).
+ JS::Rooted<JSObject*> filledView(
+ aCx, ReadableByteStreamControllerConvertPullIntoDescriptor(
+ aCx, pullIntoDescriptor, aRv));
+ if (aRv.Failed()) {
+ return;
+ }
+ // Step 13.1.2. Perform
+ // !ReadableByteStreamControllerHandleQueueDrain(controller).
+ ReadableByteStreamControllerHandleQueueDrain(aCx, aController, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+ // Step 13.1.3. Perform readIntoRequest’s chunk steps, given filledView.
+ JS::Rooted<JS::Value> filledViewValue(aCx, JS::ObjectValue(*filledView));
+ aReadIntoRequest->ChunkSteps(aCx, filledViewValue, aRv);
+ // Step 13.1.4. Return.
+ return;
+ }
+
+ // Step 13.2 If controller.[[closeRequested]] is true,
+ if (aController->CloseRequested()) {
+ // Step 13.2.1. Let e be a TypeError exception.
+ ErrorResult typeError;
+ typeError.ThrowTypeError("Close Requested True during Pull Into");
+
+ JS::Rooted<JS::Value> e(aCx);
+ MOZ_RELEASE_ASSERT(ToJSValue(aCx, std::move(typeError), &e));
+
+ // Step 13.2.2. Perform !ReadableByteStreamControllerError(controller, e).
+ ReadableByteStreamControllerError(aController, e, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Step 13.2.3. Perform readIntoRequest’s error steps, given e.
+ aReadIntoRequest->ErrorSteps(aCx, e, aRv);
+
+ // Step 13.2.4. Return.
+ return;
+ }
+ }
+
+ // Step 14. Append pullIntoDescriptor to controller.[[pendingPullIntos]].
+ aController->PendingPullIntos().insertBack(pullIntoDescriptor);
+
+ // Step 15. Perform !ReadableStreamAddReadIntoRequest(stream,
+ // readIntoRequest).
+ ReadableStreamAddReadIntoRequest(stream, aReadIntoRequest);
+
+ // Step 16, Perform
+ // !ReadableByteStreamControllerCallPullIfNeeded(controller).
+ ReadableByteStreamControllerCallPullIfNeeded(aCx, aController, aRv);
+}
+
+// https://streams.spec.whatwg.org/#set-up-readable-byte-stream-controller
+void SetUpReadableByteStreamController(
+ JSContext* aCx, ReadableStream* aStream,
+ ReadableByteStreamController* aController,
+ UnderlyingSourceAlgorithmsBase* aAlgorithms, double aHighWaterMark,
+ Maybe<uint64_t> aAutoAllocateChunkSize, ErrorResult& aRv) {
+ // Step 1. Assert: stream.[[controller]] is undefined.
+ MOZ_ASSERT(!aStream->Controller());
+
+ // Step 2. If autoAllocateChunkSize is not undefined,
+ // Step 2.1. Assert: ! IsInteger(autoAllocateChunkSize) is true. Implicit
+ // Step 2.2. Assert: autoAllocateChunkSize is positive. (Implicit by
+ // type.)
+
+ // Step 3. Set controller.[[stream]] to stream.
+ aController->SetStream(aStream);
+
+ // Step 4. Set controller.[[pullAgain]] and controller.[[pulling]] to false.
+ aController->SetPullAgain(false);
+ aController->SetPulling(false);
+
+ // Step 5. Set controller.[[byobRequest]] to null.
+ aController->SetByobRequest(nullptr);
+
+ // Step 6. Perform !ResetQueue(controller).
+ ResetQueue(aController);
+
+ // Step 7. Set controller.[[closeRequested]] and controller.[[started]] to
+ // false.
+ aController->SetCloseRequested(false);
+ aController->SetStarted(false);
+
+ // Step 8. Set controller.[[strategyHWM]] to highWaterMark.
+ aController->SetStrategyHWM(aHighWaterMark);
+
+ // Step 9. Set controller.[[pullAlgorithm]] to pullAlgorithm.
+ // Step 10. Set controller.[[cancelAlgorithm]] to cancelAlgorithm.
+ aController->SetAlgorithms(*aAlgorithms);
+
+ // Step 11. Set controller.[[autoAllocateChunkSize]] to autoAllocateChunkSize.
+ aController->SetAutoAllocateChunkSize(aAutoAllocateChunkSize);
+
+ // Step 12. Set controller.[[pendingPullIntos]] to a new empty list.
+ aController->PendingPullIntos().clear();
+
+ // Step 13. Set stream.[[controller]] to controller.
+ aStream->SetController(*aController);
+
+ // Step 14. Let startResult be the result of performing startAlgorithm.
+ JS::Rooted<JS::Value> startResult(aCx, JS::UndefinedValue());
+ RefPtr<ReadableStreamController> controller = aController;
+ aAlgorithms->StartCallback(aCx, *controller, &startResult, aRv);
+ if (aRv.Failed()) {
+ return;
+ }
+
+ // Let startPromise be a promise resolved with startResult.
+ RefPtr<Promise> startPromise =
+ Promise::CreateInfallible(aStream->GetParentObject());
+ startPromise->MaybeResolve(startResult);
+
+ // Step 16+17
+ startPromise->AddCallbacksWithCycleCollectedArgs(
+ [](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
+ ReadableByteStreamController* aController)
+ MOZ_CAN_RUN_SCRIPT_BOUNDARY {
+ MOZ_ASSERT(aController);
+
+ // Step 16.1
+ aController->SetStarted(true);
+
+ // Step 16.2
+ aController->SetPulling(false);
+
+ // Step 16.3
+ aController->SetPullAgain(false);
+
+ // Step 16.4:
+ ReadableByteStreamControllerCallPullIfNeeded(
+ aCx, MOZ_KnownLive(aController), aRv);
+ },
+ [](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
+ ReadableByteStreamController* aController) {
+ // Step 17.1
+ ReadableByteStreamControllerError(aController, aValue, aRv);
+ },
+ RefPtr(aController));
+}
+
+// https://streams.spec.whatwg.org/#set-up-readable-byte-stream-controller-from-underlying-source
+void SetUpReadableByteStreamControllerFromUnderlyingSource(
+ JSContext* aCx, ReadableStream* aStream,
+ JS::Handle<JSObject*> aUnderlyingSource,
+ UnderlyingSource& aUnderlyingSourceDict, double aHighWaterMark,
+ ErrorResult& aRv) {
+ // Step 1. Let controller be a new ReadableByteStreamController.
+ auto controller =
+ MakeRefPtr<ReadableByteStreamController>(aStream->GetParentObject());
+
+ // Step 2 - 7
+ auto algorithms = MakeRefPtr<UnderlyingSourceAlgorithms>(
+ aStream->GetParentObject(), aUnderlyingSource, aUnderlyingSourceDict);
+
+ // Step 8. Let autoAllocateChunkSize be
+ // underlyingSourceDict["autoAllocateChunkSize"], if it exists, or undefined
+ // otherwise.
+ Maybe<uint64_t> autoAllocateChunkSize = mozilla::Nothing();
+ if (aUnderlyingSourceDict.mAutoAllocateChunkSize.WasPassed()) {
+ uint64_t value = aUnderlyingSourceDict.mAutoAllocateChunkSize.Value();
+ // Step 9. If autoAllocateChunkSize is 0, then throw a TypeError
+ // exception.
+ if (value == 0) {
+ aRv.ThrowTypeError("autoAllocateChunkSize can not be zero.");
+ return;
+ }
+ autoAllocateChunkSize = mozilla::Some(value);
+ }
+
+ // Step 10. Perform ? SetUpReadableByteStreamController(stream, controller,
+ // startAlgorithm, pullAlgorithm, cancelAlgorithm, highWaterMark,
+ // autoAllocateChunkSize).
+ SetUpReadableByteStreamController(aCx, aStream, controller, algorithms,
+ aHighWaterMark, autoAllocateChunkSize, aRv);
+}
+
+} // namespace streams_abstract
+
+} // namespace mozilla::dom