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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
#include "mozilla/dom/WritableStream.h"
#include "StreamUtils.h"
#include "js/Array.h"
#include "js/PropertyAndElement.h"
#include "js/TypeDecls.h"
#include "js/Value.h"
#include "mozilla/AlreadyAddRefed.h"
#include "mozilla/Assertions.h"
#include "mozilla/Attributes.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/HoldDropJSObjects.h"
#include "mozilla/dom/AbortSignal.h"
#include "mozilla/dom/BindingCallContext.h"
#include "mozilla/dom/QueueWithSizes.h"
#include "mozilla/dom/QueuingStrategyBinding.h"
#include "mozilla/dom/ReadRequest.h"
#include "mozilla/dom/RootedDictionary.h"
#include "mozilla/dom/UnderlyingSinkBinding.h"
#include "mozilla/dom/WritableStreamBinding.h"
#include "mozilla/dom/WritableStreamDefaultController.h"
#include "mozilla/dom/WritableStreamDefaultWriter.h"
#include "nsCOMPtr.h"
#include "mozilla/dom/Promise-inl.h"
#include "nsIGlobalObject.h"
#include "nsISupports.h"
namespace mozilla::dom {
using namespace streams_abstract;
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_WITH_JS_MEMBERS(
WritableStream,
(mGlobal, mCloseRequest, mController, mInFlightWriteRequest,
mInFlightCloseRequest, mPendingAbortRequestPromise, mWriter,
mWriteRequests),
(mPendingAbortRequestReason, mStoredError))
NS_IMPL_CYCLE_COLLECTING_ADDREF(WritableStream)
NS_IMPL_CYCLE_COLLECTING_RELEASE_WITH_LAST_RELEASE(WritableStream,
LastRelease())
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(WritableStream)
NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
WritableStream::WritableStream(nsIGlobalObject* aGlobal,
HoldDropJSObjectsCaller aHoldDropCaller)
: mGlobal(aGlobal), mHoldDropCaller(aHoldDropCaller) {
if (mHoldDropCaller == HoldDropJSObjectsCaller::Implicit) {
mozilla::HoldJSObjects(this);
}
}
WritableStream::WritableStream(const GlobalObject& aGlobal,
HoldDropJSObjectsCaller aHoldDropCaller)
: mGlobal(do_QueryInterface(aGlobal.GetAsSupports())),
mHoldDropCaller(aHoldDropCaller) {
if (mHoldDropCaller == HoldDropJSObjectsCaller::Implicit) {
mozilla::HoldJSObjects(this);
}
}
WritableStream::~WritableStream() {
if (mHoldDropCaller == HoldDropJSObjectsCaller::Implicit) {
mozilla::DropJSObjects(this);
}
}
JSObject* WritableStream::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return WritableStream_Binding::Wrap(aCx, this, aGivenProto);
}
void WritableStream::DealWithRejection(JSContext* aCx,
JS::Handle<JS::Value> aError,
ErrorResult& aRv) {
// Step 1. Let state be stream.[[state]].
// Step 2. If state is "writable",
if (mState == WriterState::Writable) {
// Step 2.1. Perform ! WritableStreamStartErroring(stream, error).
StartErroring(aCx, aError, aRv);
// Step 2.2. Return.
return;
}
// Step 3. Assert: state is "erroring".
MOZ_ASSERT(mState == WriterState::Erroring);
// Step 4. Perform ! WritableStreamFinishErroring(stream).
FinishErroring(aCx, aRv);
}
void WritableStream::FinishErroring(JSContext* aCx, ErrorResult& aRv) {
// Step 1. Assert: stream.[[state]] is "erroring".
MOZ_ASSERT(mState == WriterState::Erroring);
// Step 2. Assert: ! WritableStreamHasOperationMarkedInFlight(stream) is
// false.
MOZ_ASSERT(!HasOperationMarkedInFlight());
// Step 3. Set stream.[[state]] to "errored".
mState = WriterState::Errored;
// Step 4. Perform ! stream.[[controller]].[[ErrorSteps]]().
Controller()->ErrorSteps();
// Step 5. Let storedError be stream.[[storedError]].
JS::Rooted<JS::Value> storedError(aCx, mStoredError);
// Step 6. For each writeRequest of stream.[[writeRequests]]:
for (const RefPtr<Promise>& writeRequest : mWriteRequests) {
// Step 6.1. Reject writeRequest with storedError.
writeRequest->MaybeReject(storedError);
}
// Step 7. Set stream.[[writeRequests]] to an empty list.
mWriteRequests.Clear();
// Step 8. If stream.[[pendingAbortRequest]] is undefined,
if (!mPendingAbortRequestPromise) {
// Step 8.1. Perform !
// WritableStreamRejectCloseAndClosedPromiseIfNeeded(stream).
RejectCloseAndClosedPromiseIfNeeded();
// Step 8.2. Return.
return;
}
// Step 9. Let abortRequest be stream.[[pendingAbortRequest]].
RefPtr<Promise> abortPromise = mPendingAbortRequestPromise;
JS::Rooted<JS::Value> abortReason(aCx, mPendingAbortRequestReason);
bool abortWasAlreadyErroring = mPendingAbortRequestWasAlreadyErroring;
// Step 10. Set stream.[[pendingAbortRequest]] to undefined.
SetPendingAbortRequest(nullptr, JS::UndefinedHandleValue, false);
// Step 11. If abortRequest’s was already erroring is true,
if (abortWasAlreadyErroring) {
// Step 11.1. Reject abortRequest’s promise with storedError.
abortPromise->MaybeReject(storedError);
// Step 11.2. Perform !
// WritableStreamRejectCloseAndClosedPromiseIfNeeded(stream).
RejectCloseAndClosedPromiseIfNeeded();
// Step 11.3. Return.
return;
}
// Step 12. Let promise be !
// stream.[[controller]].[[AbortSteps]](abortRequest’s reason).
RefPtr<WritableStreamDefaultController> controller = mController;
RefPtr<Promise> promise = controller->AbortSteps(aCx, abortReason, aRv);
if (aRv.Failed()) {
return;
}
// Step 13 + 14.
promise->AddCallbacksWithCycleCollectedArgs(
[](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
Promise* aAbortRequestPromise, WritableStream* aStream) {
// Step 13. Upon fulfillment of promise,
// Step 13.1. Resolve abortRequest’s promise with undefined.
aAbortRequestPromise->MaybeResolveWithUndefined();
// Step 13.2. Perform !
// WritableStreamRejectCloseAndClosedPromiseIfNeeded(stream).
aStream->RejectCloseAndClosedPromiseIfNeeded();
},
[](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
Promise* aAbortRequestPromise, WritableStream* aStream) {
// Step 14. Upon rejection of promise with reason reason,
// Step 14.1. Reject abortRequest’s promise with reason.
aAbortRequestPromise->MaybeReject(aValue);
// Step 14.2. Perform !
// WritableStreamRejectCloseAndClosedPromiseIfNeeded(stream).
aStream->RejectCloseAndClosedPromiseIfNeeded();
},
RefPtr(abortPromise), RefPtr(this));
}
void WritableStream::FinishInFlightClose() {
// Step 1. Assert: stream.[[inFlightCloseRequest]] is not undefined.
MOZ_ASSERT(mInFlightCloseRequest);
// Step 2. Resolve stream.[[inFlightCloseRequest]] with undefined.
mInFlightCloseRequest->MaybeResolveWithUndefined();
// Step 3. Set stream.[[inFlightCloseRequest]] to undefined.
mInFlightCloseRequest = nullptr;
// Step 4. Let state be stream.[[state]].
// Step 5. Assert: stream.[[state]] is "writable" or "erroring".
MOZ_ASSERT(mState == WriterState::Writable ||
mState == WriterState::Erroring);
// Step 6. If state is "erroring",
if (mState == WriterState::Erroring) {
// Step 6.1. Set stream.[[storedError]] to undefined.
mStoredError.setUndefined();
// Step 6.2. If stream.[[pendingAbortRequest]] is not undefined,
if (mPendingAbortRequestPromise) {
// Step 6.2.1. Resolve stream.[[pendingAbortRequest]]'s promise with
// undefined.
mPendingAbortRequestPromise->MaybeResolveWithUndefined();
// Step 6.2.2. Set stream.[[pendingAbortRequest]] to undefined.
SetPendingAbortRequest(nullptr, JS::UndefinedHandleValue, false);
}
}
// Step 7. Set stream.[[state]] to "closed".
mState = WriterState::Closed;
// Step 8. Let writer be stream.[[writer]].
// Step 9. If writer is not undefined, resolve writer.[[closedPromise]] with
// undefined.
if (mWriter) {
mWriter->ClosedPromise()->MaybeResolveWithUndefined();
}
// Step 10. Assert: stream.[[pendingAbortRequest]] is undefined.
MOZ_ASSERT(!mPendingAbortRequestPromise);
// Assert: stream.[[storedError]] is undefined.
MOZ_ASSERT(mStoredError.isUndefined());
}
void WritableStream::FinishInFlightCloseWithError(JSContext* aCx,
JS::Handle<JS::Value> aError,
ErrorResult& aRv) {
// Step 1. Assert: stream.[[inFlightCloseRequest]] is not undefined.
MOZ_ASSERT(mInFlightCloseRequest);
// Step 2. Reject stream.[[inFlightCloseRequest]] with error.
mInFlightCloseRequest->MaybeReject(aError);
// Step 3. Set stream.[[inFlightCloseRequest]] to undefined.
mInFlightCloseRequest = nullptr;
// Step 4. Assert: stream.[[state]] is "writable" or "erroring".
MOZ_ASSERT(mState == WriterState::Writable ||
mState == WriterState::Erroring);
// Step 5. If stream.[[pendingAbortRequest]] is not undefined,
if (mPendingAbortRequestPromise) {
// Step 5.1. Reject stream.[[pendingAbortRequest]]'s promise with error.
mPendingAbortRequestPromise->MaybeReject(aError);
// Step 5.2. Set stream.[[pendingAbortRequest]] to undefined.
SetPendingAbortRequest(nullptr, JS::UndefinedHandleValue, false);
}
// Step 6. Perform ! WritableStreamDealWithRejection(stream, error).
DealWithRejection(aCx, aError, aRv);
}
void WritableStream::FinishInFlightWrite() {
// Step 1. Assert: stream.[[inFlightWriteRequest]] is not undefined.
MOZ_ASSERT(mInFlightWriteRequest);
// Step 2. Resolve stream.[[inFlightWriteRequest]] with undefined.
mInFlightWriteRequest->MaybeResolveWithUndefined();
// Step 3. Set stream.[[inFlightWriteRequest]] to undefined.
mInFlightWriteRequest = nullptr;
}
void WritableStream::FinishInFlightWriteWithError(JSContext* aCx,
JS::Handle<JS::Value> aError,
ErrorResult& aRv) {
// Step 1. Assert: stream.[[inFlightWriteRequest]] is not undefined.
MOZ_ASSERT(mInFlightWriteRequest);
// Step 2. Reject stream.[[inFlightWriteRequest]] with error.
mInFlightWriteRequest->MaybeReject(aError);
// Step 3. Set stream.[[inFlightWriteRequest]] to undefined.
mInFlightWriteRequest = nullptr;
// Step 4. Assert: stream.[[state]] is "writable" or "erroring".
MOZ_ASSERT(mState == WriterState::Writable ||
mState == WriterState::Erroring);
// Step 5. Perform ! WritableStreamDealWithRejection(stream, error).
DealWithRejection(aCx, aError, aRv);
}
void WritableStream::MarkCloseRequestInFlight() {
// Step 1. Assert: stream.[[inFlightCloseRequest]] is undefined.
MOZ_ASSERT(!mInFlightCloseRequest);
// Step 2. Assert: stream.[[closeRequest]] is not undefined.
MOZ_ASSERT(mCloseRequest);
// Step 3. Set stream.[[inFlightCloseRequest]] to stream.[[closeRequest]].
mInFlightCloseRequest = mCloseRequest;
// Step 4. Set stream.[[closeRequest]] to undefined.
mCloseRequest = nullptr;
}
void WritableStream::MarkFirstWriteRequestInFlight() {
// Step 1. Assert: stream.[[inFlightWriteRequest]] is undefined.
MOZ_ASSERT(!mInFlightWriteRequest);
// Step 2. Assert: stream.[[writeRequests]] is not empty.
MOZ_ASSERT(!mWriteRequests.IsEmpty());
// Step 3. Let writeRequest be stream.[[writeRequests]][0].
RefPtr<Promise> writeRequest = mWriteRequests.ElementAt(0);
// Step 4. Remove writeRequest from stream.[[writeRequests]].
mWriteRequests.RemoveElementAt(0);
// Step 5. Set stream.[[inFlightWriteRequest]] to writeRequest.
mInFlightWriteRequest = writeRequest;
}
void WritableStream::RejectCloseAndClosedPromiseIfNeeded() {
// Step 1. Assert: stream.[[state]] is "errored".
MOZ_ASSERT(mState == WriterState::Errored);
JS::Rooted<JS::Value> storedError(RootingCx(), mStoredError);
// Step 2. If stream.[[closeRequest]] is not undefined,
if (mCloseRequest) {
// Step 2.1. Assert: stream.[[inFlightCloseRequest]] is undefined.
MOZ_ASSERT(!mInFlightCloseRequest);
// Step 2.2. Reject stream.[[closeRequest]] with stream.[[storedError]].
mCloseRequest->MaybeReject(storedError);
// Step 2.3. Set stream.[[closeRequest]] to undefined.
mCloseRequest = nullptr;
}
// Step 3. Let writer be stream.[[writer]].
RefPtr<WritableStreamDefaultWriter> writer = mWriter;
// Step 4. If writer is not undefined,
if (writer) {
// Step 4.1. Reject writer.[[closedPromise]] with stream.[[storedError]].
RefPtr<Promise> closedPromise = writer->ClosedPromise();
closedPromise->MaybeReject(storedError);
// Step 4.2. Set writer.[[closedPromise]].[[PromiseIsHandled]] to true.
closedPromise->SetSettledPromiseIsHandled();
}
}
void WritableStream::StartErroring(JSContext* aCx,
JS::Handle<JS::Value> aReason,
ErrorResult& aRv) {
// Step 1. Assert: stream.[[storedError]] is undefined.
MOZ_ASSERT(mStoredError.isUndefined());
// Step 2. Assert: stream.[[state]] is "writable".
MOZ_ASSERT(mState == WriterState::Writable);
// Step 3. Let controller be stream.[[controller]].
RefPtr<WritableStreamDefaultController> controller = mController;
// Step 4. Assert: controller is not undefined.
MOZ_ASSERT(controller);
// Step 5. Set stream.[[state]] to "erroring".
mState = WriterState::Erroring;
// Step 6. Set stream.[[storedError]] to reason.
mStoredError = aReason;
// Step 7. Let writer be stream.[[writer]].
RefPtr<WritableStreamDefaultWriter> writer = mWriter;
// Step 8. If writer is not undefined, perform !
// WritableStreamDefaultWriterEnsureReadyPromiseRejected(writer, reason).
if (writer) {
WritableStreamDefaultWriterEnsureReadyPromiseRejected(writer, aReason);
}
// Step 9. If ! WritableStreamHasOperationMarkedInFlight(stream) is false
// and controller.[[started]] is true,
// perform !WritableStreamFinishErroring(stream).
if (!HasOperationMarkedInFlight() && controller->Started()) {
FinishErroring(aCx, aRv);
}
}
void WritableStream::UpdateBackpressure(bool aBackpressure) {
// Step 1. Assert: stream.[[state]] is "writable".
MOZ_ASSERT(mState == WriterState::Writable);
// Step 2. Assert: ! WritableStreamCloseQueuedOrInFlight(stream) is false.
MOZ_ASSERT(!CloseQueuedOrInFlight());
// Step 3. Let writer be stream.[[writer]].
RefPtr<WritableStreamDefaultWriter> writer = mWriter;
// Step 4. If writer is not undefined and backpressure is not
// stream.[[backpressure]],
if (writer && aBackpressure != mBackpressure) {
// Step 4.1. If backpressure is true, set writer.[[readyPromise]] to a new
// promise.
if (aBackpressure) {
RefPtr<Promise> promise =
Promise::CreateInfallible(writer->GetParentObject());
writer->SetReadyPromise(promise);
} else {
// Step 4.2. Otherwise,
// Step 4.2.1. Assert: backpressure is false.
// Step 4.2.2. Resolve writer.[[readyPromise]] with undefined.
writer->ReadyPromise()->MaybeResolveWithUndefined();
}
}
// Step 5. Set stream.[[backpressure]] to backpressure.
mBackpressure = aBackpressure;
}
already_AddRefed<WritableStream> WritableStream::Constructor(
const GlobalObject& aGlobal,
const Optional<JS::Handle<JSObject*>>& aUnderlyingSink,
const QueuingStrategy& aStrategy, ErrorResult& aRv) {
// Step 1. If underlyingSink is missing, set it to null.
JS::Rooted<JSObject*> underlyingSinkObj(
aGlobal.Context(),
aUnderlyingSink.WasPassed() ? aUnderlyingSink.Value() : nullptr);
// Step 2. Let underlyingSinkDict be underlyingSink, converted to
// an IDL value of type UnderlyingSink.
RootedDictionary<UnderlyingSink> underlyingSinkDict(aGlobal.Context());
if (underlyingSinkObj) {
JS::Rooted<JS::Value> objValue(aGlobal.Context(),
JS::ObjectValue(*underlyingSinkObj));
dom::BindingCallContext callCx(aGlobal.Context(),
"WritableStream.constructor");
aRv.MightThrowJSException();
if (!underlyingSinkDict.Init(callCx, objValue)) {
aRv.StealExceptionFromJSContext(aGlobal.Context());
return nullptr;
}
}
// Step 3. If underlyingSinkDict["type"] exists, throw a RangeError exception.
if (!underlyingSinkDict.mType.isUndefined()) {
aRv.ThrowRangeError("Implementation preserved member 'type'");
return nullptr;
}
// Step 4. Perform ! InitializeWritableStream(this).
RefPtr<WritableStream> writableStream =
new WritableStream(aGlobal, HoldDropJSObjectsCaller::Implicit);
// Step 5. Let sizeAlgorithm be ! ExtractSizeAlgorithm(strategy).
//
// Implementation Note: The specification demands that if the size doesn't
// exist, we instead would provide an algorithm that returns 1. Instead, we
// will teach callers that a missing callback should simply return 1, rather
// than gin up a fake callback here.
//
// This decision may need to be revisited if the default action ever diverges
// within the specification.
RefPtr<QueuingStrategySize> sizeAlgorithm =
aStrategy.mSize.WasPassed() ? &aStrategy.mSize.Value() : nullptr;
// Step 6. Let highWaterMark be ? ExtractHighWaterMark(strategy, 1).
double highWaterMark = ExtractHighWaterMark(aStrategy, 1, aRv);
if (aRv.Failed()) {
return nullptr;
}
// Step 7. Perform ? SetUpWritableStreamDefaultControllerFromUnderlyingSink(
// this, underlyingSink, underlyingSinkDict, highWaterMark, sizeAlgorithm).
SetUpWritableStreamDefaultControllerFromUnderlyingSink(
aGlobal.Context(), writableStream, underlyingSinkObj, underlyingSinkDict,
highWaterMark, sizeAlgorithm, aRv);
if (aRv.Failed()) {
return nullptr;
}
return writableStream.forget();
}
namespace streams_abstract {
already_AddRefed<Promise> WritableStreamAbort(JSContext* aCx,
WritableStream* aStream,
JS::Handle<JS::Value> aReason,
ErrorResult& aRv) {
// Step 1. If stream.[[state]] is "closed" or "errored", return a promise
// resolved with undefined.
if (aStream->State() == WritableStream::WriterState::Closed ||
aStream->State() == WritableStream::WriterState::Errored) {
RefPtr<Promise> promise =
Promise::CreateInfallible(aStream->GetParentObject());
promise->MaybeResolveWithUndefined();
return promise.forget();
}
// Step 2. Signal abort on stream.[[controller]].[[signal]] with reason.
RefPtr<WritableStreamDefaultController> controller = aStream->Controller();
controller->Signal()->SignalAbort(aReason);
// Step 3. Let state be stream.[[state]].
WritableStream::WriterState state = aStream->State();
// Step 4. If state is "closed" or "errored", return a promise resolved with
// undefined. Note: We re-check the state because signaling abort runs author
// code and that might have changed the state.
if (aStream->State() == WritableStream::WriterState::Closed ||
aStream->State() == WritableStream::WriterState::Errored) {
RefPtr<Promise> promise =
Promise::CreateInfallible(aStream->GetParentObject());
promise->MaybeResolveWithUndefined();
return promise.forget();
}
// Step 5. If stream.[[pendingAbortRequest]] is not undefined, return
// stream.[[pendingAbortRequest]]'s promise.
if (aStream->GetPendingAbortRequestPromise()) {
RefPtr<Promise> promise = aStream->GetPendingAbortRequestPromise();
return promise.forget();
}
// Step 6. Assert: state is "writable" or "erroring".
MOZ_ASSERT(state == WritableStream::WriterState::Writable ||
state == WritableStream::WriterState::Erroring);
// Step 7. Let wasAlreadyErroring be false.
bool wasAlreadyErroring = false;
// Step 8. If state is "erroring",
JS::Rooted<JS::Value> reason(aCx, aReason);
if (state == WritableStream::WriterState::Erroring) {
// Step 8.1. Set wasAlreadyErroring to true.
wasAlreadyErroring = true;
// Step 8.2. Set reason to undefined.
reason.setUndefined();
}
// Step 9. Let promise be a new promise.
RefPtr<Promise> promise =
Promise::CreateInfallible(aStream->GetParentObject());
// Step 10. Set stream.[[pendingAbortRequest]] to a new pending abort request
// whose promise is promise, reason is reason, and was already erroring is
// wasAlreadyErroring.
aStream->SetPendingAbortRequest(promise, reason, wasAlreadyErroring);
// Step 11. If wasAlreadyErroring is false, perform !
// WritableStreamStartErroring(stream, reason).
if (!wasAlreadyErroring) {
aStream->StartErroring(aCx, reason, aRv);
if (aRv.Failed()) {
return nullptr;
}
}
// Step 12. Return promise.
return promise.forget();
}
} // namespace streams_abstract
already_AddRefed<Promise> WritableStream::Abort(JSContext* aCx,
JS::Handle<JS::Value> aReason,
ErrorResult& aRv) {
// Step 1. If ! IsWritableStreamLocked(this) is true, return a promise
// rejected with a TypeError exception.
if (Locked()) {
return Promise::CreateRejectedWithTypeError(
GetParentObject(), "Canceled Locked Stream"_ns, aRv);
}
// Step 2. Return ! WritableStreamAbort(this, reason).
RefPtr<WritableStream> thisRefPtr = this;
return WritableStreamAbort(aCx, thisRefPtr, aReason, aRv);
}
namespace streams_abstract {
already_AddRefed<Promise> WritableStreamClose(JSContext* aCx,
WritableStream* aStream,
ErrorResult& aRv) {
// Step 1. Let state be stream.[[state]].
WritableStream::WriterState state = aStream->State();
// Step 2. If state is "closed" or "errored", return a promise rejected with a
// TypeError exception.
if (state == WritableStream::WriterState::Closed ||
state == WritableStream::WriterState::Errored) {
return Promise::CreateRejectedWithTypeError(
aStream->GetParentObject(),
"Can not close stream after closing or error"_ns, aRv);
}
// Step 3. Assert: state is "writable" or "erroring".
MOZ_ASSERT(state == WritableStream::WriterState::Writable ||
state == WritableStream::WriterState::Erroring);
// Step 4. Assert: ! WritableStreamCloseQueuedOrInFlight(stream) is false.
MOZ_ASSERT(!aStream->CloseQueuedOrInFlight());
// Step 5. Let promise be a new promise.
RefPtr<Promise> promise =
Promise::CreateInfallible(aStream->GetParentObject());
// Step 6. Set stream.[[closeRequest]] to promise.
aStream->SetCloseRequest(promise);
// Step 7. Let writer be stream.[[writer]].
RefPtr<WritableStreamDefaultWriter> writer = aStream->GetWriter();
// Step 8. If writer is not undefined, and stream.[[backpressure]] is true,
// and state is "writable", resolve writer.[[readyPromise]] with undefined.
if (writer && aStream->Backpressure() &&
state == WritableStream::WriterState::Writable) {
writer->ReadyPromise()->MaybeResolveWithUndefined();
}
// Step 9.
// Perform ! WritableStreamDefaultControllerClose(stream.[[controller]]).
RefPtr<WritableStreamDefaultController> controller = aStream->Controller();
WritableStreamDefaultControllerClose(aCx, controller, aRv);
if (aRv.Failed()) {
return nullptr;
}
// Step 10. Return promise.
return promise.forget();
}
} // namespace streams_abstract
already_AddRefed<Promise> WritableStream::Close(JSContext* aCx,
ErrorResult& aRv) {
// Step 1. If ! IsWritableStreamLocked(this) is true, return a promise
// rejected with a TypeError exception.
if (Locked()) {
return Promise::CreateRejectedWithTypeError(
GetParentObject(), "Can not close locked stream"_ns, aRv);
}
// Step 2. If ! WritableStreamCloseQueuedOrInFlight(this) is true, return a
// promise rejected with a TypeError exception.
if (CloseQueuedOrInFlight()) {
return Promise::CreateRejectedWithTypeError(
GetParentObject(), "Stream is already closing"_ns, aRv);
}
// Step 3. Return ! WritableStreamClose(this).
RefPtr<WritableStream> thisRefPtr = this;
return WritableStreamClose(aCx, thisRefPtr, aRv);
}
namespace streams_abstract {
already_AddRefed<WritableStreamDefaultWriter>
AcquireWritableStreamDefaultWriter(WritableStream* aStream, ErrorResult& aRv) {
// Step 1. Let writer be a new WritableStreamDefaultWriter.
RefPtr<WritableStreamDefaultWriter> writer =
new WritableStreamDefaultWriter(aStream->GetParentObject());
// Step 2. Perform ? SetUpWritableStreamDefaultWriter(writer, stream).
SetUpWritableStreamDefaultWriter(writer, aStream, aRv);
if (aRv.Failed()) {
return nullptr;
}
// Step 3. Return writer.
return writer.forget();
}
} // namespace streams_abstract
already_AddRefed<WritableStream> WritableStream::CreateAbstract(
JSContext* aCx, nsIGlobalObject* aGlobal,
UnderlyingSinkAlgorithmsBase* aAlgorithms, double aHighWaterMark,
QueuingStrategySize* aSizeAlgorithm, ErrorResult& aRv) {
// Step 1: Assert: ! IsNonNegativeNumber(highWaterMark) is true.
MOZ_ASSERT(IsNonNegativeNumber(aHighWaterMark));
// Step 2: Let stream be a new WritableStream.
// Step 3: Perform ! InitializeWritableStream(stream).
RefPtr<WritableStream> stream = new WritableStream(
aGlobal, WritableStream::HoldDropJSObjectsCaller::Implicit);
// Step 4: Let controller be a new WritableStreamDefaultController.
auto controller =
MakeRefPtr<WritableStreamDefaultController>(aGlobal, *stream);
// Step 5: Perform ? SetUpWritableStreamDefaultController(stream, controller,
// startAlgorithm, writeAlgorithm, closeAlgorithm, abortAlgorithm,
// highWaterMark, sizeAlgorithm).
SetUpWritableStreamDefaultController(aCx, stream, controller, aAlgorithms,
aHighWaterMark, aSizeAlgorithm, aRv);
if (aRv.Failed()) {
return nullptr;
}
// Step 6: Return stream.
return stream.forget();
}
already_AddRefed<WritableStreamDefaultWriter> WritableStream::GetWriter(
ErrorResult& aRv) {
return AcquireWritableStreamDefaultWriter(this, aRv);
}
namespace streams_abstract {
already_AddRefed<Promise> WritableStreamAddWriteRequest(
WritableStream* aStream) {
// Step 1. Assert: ! IsWritableStreamLocked(stream) is true.
MOZ_ASSERT(IsWritableStreamLocked(aStream));
// Step 2. Assert: stream.[[state]] is "writable".
MOZ_ASSERT(aStream->State() == WritableStream::WriterState::Writable);
// Step 3. Let promise be a new promise.
RefPtr<Promise> promise =
Promise::CreateInfallible(aStream->GetParentObject());
// Step 4. Append promise to stream.[[writeRequests]].
aStream->AppendWriteRequest(promise);
// Step 5. Return promise.
return promise.forget();
}
} // namespace streams_abstract
// _BOUNDARY because `aAlgorithms->StartCallback` (called by
// SetUpWritableStreamDefaultController below) should not be able to run script
// in this case.
MOZ_CAN_RUN_SCRIPT_BOUNDARY void WritableStream::SetUpNative(
JSContext* aCx, UnderlyingSinkAlgorithmsWrapper& aAlgorithms,
Maybe<double> aHighWaterMark, QueuingStrategySize* aSizeAlgorithm,
ErrorResult& aRv) {
// an optional number highWaterMark (default 1)
double highWaterMark = aHighWaterMark.valueOr(1);
// and if given, highWaterMark must be a non-negative, non-NaN number.
MOZ_ASSERT(IsNonNegativeNumber(highWaterMark));
// Step 1: Let startAlgorithm be an algorithm that returns undefined.
// Step 2: Let closeAlgorithmWrapper be an algorithm that runs these steps:
// Step 3: Let abortAlgorithmWrapper be an algorithm that runs these steps:
// (Covered by UnderlyingSinkAlgorithmsWrapper)
// Step 4: If sizeAlgorithm was not given, then set it to an algorithm that
// returns 1. (Callers will treat nullptr as such, see
// WritableStream::Constructor for details)
// Step 5: Perform ! InitializeWritableStream(stream).
// (Covered by the constructor)
// Step 6: Let controller be a new WritableStreamDefaultController.
auto controller =
MakeRefPtr<WritableStreamDefaultController>(GetParentObject(), *this);
// Step 7: Perform ! SetUpWritableStreamDefaultController(stream, controller,
// startAlgorithm, writeAlgorithm, closeAlgorithmWrapper,
// abortAlgorithmWrapper, highWaterMark, sizeAlgorithm).
SetUpWritableStreamDefaultController(aCx, this, controller, &aAlgorithms,
highWaterMark, aSizeAlgorithm, aRv);
}
already_AddRefed<WritableStream> WritableStream::CreateNative(
JSContext* aCx, nsIGlobalObject& aGlobal,
UnderlyingSinkAlgorithmsWrapper& aAlgorithms, Maybe<double> aHighWaterMark,
QueuingStrategySize* aSizeAlgorithm, ErrorResult& aRv) {
RefPtr<WritableStream> stream = new WritableStream(
&aGlobal, WritableStream::HoldDropJSObjectsCaller::Implicit);
stream->SetUpNative(aCx, aAlgorithms, aHighWaterMark, aSizeAlgorithm, aRv);
if (aRv.Failed()) {
return nullptr;
}
return stream.forget();
}
// To error a WritableStream stream given a JavaScript value e, perform !
// WritableStreamDefaultControllerErrorIfNeeded(stream.[[controller]], e).
void WritableStream::ErrorNative(JSContext* aCx, JS::Handle<JS::Value> aError,
ErrorResult& aRv) {
// MOZ_KnownLive here instead of MOZ_KNOWN_LIVE at the field, because
// mController is set outside of the constructor
WritableStreamDefaultControllerErrorIfNeeded(aCx, MOZ_KnownLive(mController),
aError, aRv);
}
} // namespace mozilla::dom