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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 "ReadableStreamTee.h"
#include "ReadIntoRequest.h"
#include "TeeState.h"
#include "js/Exception.h"
#include "js/TypeDecls.h"
#include "js/experimental/TypedData.h"
#include "mozilla/dom/ByteStreamHelpers.h"
#include "mozilla/dom/Promise-inl.h"
#include "mozilla/dom/ReadableStream.h"
#include "mozilla/dom/ReadableStreamBYOBReader.h"
#include "mozilla/dom/ReadableStreamDefaultController.h"
#include "mozilla/dom/ReadableStreamGenericReader.h"
#include "mozilla/dom/ReadableStreamDefaultReader.h"
#include "mozilla/dom/ReadableByteStreamController.h"
#include "mozilla/dom/UnderlyingSourceBinding.h"
#include "mozilla/dom/UnderlyingSourceCallbackHelpers.h"
#include "nsCycleCollectionParticipant.h"
#include "mozilla/CycleCollectedJSContext.h"
namespace mozilla::dom {
using namespace streams_abstract;
NS_IMPL_CYCLE_COLLECTION_INHERITED(ReadableStreamDefaultTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase, mTeeState)
NS_IMPL_ADDREF_INHERITED(ReadableStreamDefaultTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase)
NS_IMPL_RELEASE_INHERITED(ReadableStreamDefaultTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(
ReadableStreamDefaultTeeSourceAlgorithms)
NS_INTERFACE_MAP_END_INHERITING(UnderlyingSourceAlgorithmsBase)
already_AddRefed<Promise>
ReadableStreamDefaultTeeSourceAlgorithms::PullCallback(
JSContext* aCx, ReadableStreamController& aController, ErrorResult& aRv) {
nsCOMPtr<nsIGlobalObject> global = aController.GetParentObject();
mTeeState->PullCallback(aCx, global, aRv);
if (!aRv.Failed()) {
return Promise::CreateResolvedWithUndefined(global, aRv);
}
return nullptr;
}
NS_IMPL_CYCLE_COLLECTION_CLASS(ReadableStreamDefaultTeeReadRequest)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(
ReadableStreamDefaultTeeReadRequest, ReadRequest)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mTeeState)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(
ReadableStreamDefaultTeeReadRequest, ReadRequest)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mTeeState)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_ADDREF_INHERITED(ReadableStreamDefaultTeeReadRequest, ReadRequest)
NS_IMPL_RELEASE_INHERITED(ReadableStreamDefaultTeeReadRequest, ReadRequest)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ReadableStreamDefaultTeeReadRequest)
NS_INTERFACE_MAP_END_INHERITING(ReadRequest)
void ReadableStreamDefaultTeeReadRequest::ChunkSteps(
JSContext* aCx, JS::Handle<JS::Value> aChunk, ErrorResult& aRv) {
// Step 1.
class ReadableStreamDefaultTeeReadRequestChunkSteps
: public MicroTaskRunnable {
// Virtually const, but is cycle collected
MOZ_KNOWN_LIVE RefPtr<TeeState> mTeeState;
JS::PersistentRooted<JS::Value> mChunk;
public:
ReadableStreamDefaultTeeReadRequestChunkSteps(JSContext* aCx,
TeeState* aTeeState,
JS::Handle<JS::Value> aChunk)
: mTeeState(aTeeState), mChunk(aCx, aChunk) {}
MOZ_CAN_RUN_SCRIPT
void Run(AutoSlowOperation& aAso) override {
AutoJSAPI jsapi;
if (NS_WARN_IF(!jsapi.Init(mTeeState->GetStream()->GetParentObject()))) {
return;
}
JSContext* cx = jsapi.cx();
// Step Numbering below is relative to Chunk steps Microtask:
//
// Step 1.
mTeeState->SetReadAgain(false);
// Step 2.
JS::Rooted<JS::Value> chunk1(cx, mChunk);
JS::Rooted<JS::Value> chunk2(cx, mChunk);
// Step 3. Skipped until we implement cloneForBranch2 path.
MOZ_RELEASE_ASSERT(!mTeeState->CloneForBranch2());
// Step 4.
if (!mTeeState->Canceled1()) {
IgnoredErrorResult rv;
// Since we controlled the creation of the two stream branches, we know
// they both have default controllers.
RefPtr<ReadableStreamDefaultController> controller(
mTeeState->Branch1()->DefaultController());
ReadableStreamDefaultControllerEnqueue(cx, controller, chunk1, rv);
(void)NS_WARN_IF(rv.Failed());
}
// Step 5.
if (!mTeeState->Canceled2()) {
IgnoredErrorResult rv;
RefPtr<ReadableStreamDefaultController> controller(
mTeeState->Branch2()->DefaultController());
ReadableStreamDefaultControllerEnqueue(cx, controller, chunk2, rv);
(void)NS_WARN_IF(rv.Failed());
}
// Step 6.
mTeeState->SetReading(false);
// Step 7. If |readAgain| is true, perform |pullAlgorithm|.
if (mTeeState->ReadAgain()) {
IgnoredErrorResult rv;
nsCOMPtr<nsIGlobalObject> global(
mTeeState->GetStream()->GetParentObject());
mTeeState->PullCallback(cx, global, rv);
(void)NS_WARN_IF(rv.Failed());
}
}
bool Suppressed() override {
nsIGlobalObject* global = mTeeState->GetStream()->GetParentObject();
return global && global->IsInSyncOperation();
}
};
RefPtr<ReadableStreamDefaultTeeReadRequestChunkSteps> task =
MakeRefPtr<ReadableStreamDefaultTeeReadRequestChunkSteps>(aCx, mTeeState,
aChunk);
CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
}
void ReadableStreamDefaultTeeReadRequest::CloseSteps(JSContext* aCx,
ErrorResult& aRv) {
// Step Numbering below is relative to 'close steps' of
//
// Step 1.
mTeeState->SetReading(false);
// Step 2.
if (!mTeeState->Canceled1()) {
RefPtr<ReadableStreamDefaultController> controller(
mTeeState->Branch1()->DefaultController());
ReadableStreamDefaultControllerClose(aCx, controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 3.
if (!mTeeState->Canceled2()) {
RefPtr<ReadableStreamDefaultController> controller(
mTeeState->Branch2()->DefaultController());
ReadableStreamDefaultControllerClose(aCx, controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 4.
if (!mTeeState->Canceled1() || !mTeeState->Canceled2()) {
mTeeState->CancelPromise()->MaybeResolveWithUndefined();
}
}
void ReadableStreamDefaultTeeReadRequest::ErrorSteps(
JSContext* aCx, JS::Handle<JS::Value> aError, ErrorResult& aRv) {
mTeeState->SetReading(false);
}
MOZ_CAN_RUN_SCRIPT void PullWithDefaultReader(JSContext* aCx,
TeeState* aTeeState,
ErrorResult& aRv);
MOZ_CAN_RUN_SCRIPT void PullWithBYOBReader(JSContext* aCx, TeeState* aTeeState,
JS::Handle<JSObject*> aView,
TeeBranch aForBranch,
ErrorResult& aRv);
// Algorithm described in
// 17 and Steps 18, genericized across branch numbers:
//
// Note: As specified this algorithm always returns a promise resolved with
// undefined, however as some places immediately discard said promise, we
// provide this version which doesn't return a promise.
//
// NativeByteStreamTeePullAlgorithm, which implements
// UnderlyingSourcePullCallbackHelper is the version which provies the return
// promise.
MOZ_CAN_RUN_SCRIPT void ByteStreamTeePullAlgorithm(JSContext* aCx,
TeeBranch aForBranch,
TeeState* aTeeState,
ErrorResult& aRv) {
// Step {17,18}.1: If reading is true,
if (aTeeState->Reading()) {
// Step {17,18}.1.1: Set readAgainForBranch{1,2} to true.
aTeeState->SetReadAgainForBranch(aForBranch, true);
// Step {17,18}.1.1: Return a promise resolved with undefined.
return;
}
// Step {17,18}.2: Set reading to true.
aTeeState->SetReading(true);
// Step {17,18}.3: Let byobRequest be
// !ReadableByteStreamControllerGetBYOBRequest(branch{1,2}.[[controller]]).
RefPtr<ReadableStreamBYOBRequest> byobRequest =
ReadableByteStreamControllerGetBYOBRequest(
aCx, aTeeState->Branch(aForBranch)->Controller()->AsByte(), aRv);
if (aRv.Failed()) {
return;
}
// Step {17,18}.4: If byobRequest is null, perform pullWithDefaultReader.
if (!byobRequest) {
PullWithDefaultReader(aCx, aTeeState, aRv);
} else {
// Step {17,18}.5: Otherwise, perform pullWithBYOBReader, given
// byobRequest.[[view]] and {false, true}.
JS::Rooted<JSObject*> view(aCx, byobRequest->View());
PullWithBYOBReader(aCx, aTeeState, view, aForBranch, aRv);
}
// Step {17,18}.6: Return a promise resolved with undefined.
}
class ByteStreamTeeSourceAlgorithms final
: public UnderlyingSourceAlgorithmsBase {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ByteStreamTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase)
ByteStreamTeeSourceAlgorithms(TeeState* aTeeState, TeeBranch aBranch)
: mTeeState(aTeeState), mBranch(aBranch) {}
MOZ_CAN_RUN_SCRIPT void StartCallback(JSContext* aCx,
ReadableStreamController& aController,
JS::MutableHandle<JS::Value> aRetVal,
ErrorResult& aRv) override {
// Step 21: Let startAlgorithm be an algorithm that returns undefined.
aRetVal.setUndefined();
}
// Step 17, 18
MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> PullCallback(
JSContext* aCx, ReadableStreamController& aController,
ErrorResult& aRv) override {
// Step 1 - 5
ByteStreamTeePullAlgorithm(aCx, mBranch, MOZ_KnownLive(mTeeState), aRv);
// Step 6: Return a promise resolved with undefined.
return Promise::CreateResolvedWithUndefined(
mTeeState->GetStream()->GetParentObject(), aRv);
}
// Step 19, 20
MOZ_CAN_RUN_SCRIPT already_AddRefed<Promise> CancelCallback(
JSContext* aCx, const Optional<JS::Handle<JS::Value>>& aReason,
ErrorResult& aRv) override {
// Step 1.
mTeeState->SetCanceled(mBranch, true);
// Step 2.
mTeeState->SetReason(mBranch, aReason.Value());
// Step 3.
if (mTeeState->Canceled(otherStream())) {
// Step 3.1
JS::Rooted<JSObject*> compositeReason(aCx, JS::NewArrayObject(aCx, 2));
if (!compositeReason) {
aRv.StealExceptionFromJSContext(aCx);
return nullptr;
}
JS::Rooted<JS::Value> reason1(aCx, mTeeState->Reason1());
if (!JS_SetElement(aCx, compositeReason, 0, reason1)) {
aRv.StealExceptionFromJSContext(aCx);
return nullptr;
}
JS::Rooted<JS::Value> reason2(aCx, mTeeState->Reason2());
if (!JS_SetElement(aCx, compositeReason, 1, reason2)) {
aRv.StealExceptionFromJSContext(aCx);
return nullptr;
}
// Step 3.2
JS::Rooted<JS::Value> compositeReasonValue(
aCx, JS::ObjectValue(*compositeReason));
RefPtr<ReadableStream> stream(mTeeState->GetStream());
RefPtr<Promise> cancelResult =
ReadableStreamCancel(aCx, stream, compositeReasonValue, aRv);
if (aRv.Failed()) {
return nullptr;
}
// Step 3.3
mTeeState->CancelPromise()->MaybeResolve(cancelResult);
}
// Step 4.
return do_AddRef(mTeeState->CancelPromise());
};
protected:
~ByteStreamTeeSourceAlgorithms() override = default;
private:
TeeBranch otherStream() { return OtherTeeBranch(mBranch); }
RefPtr<TeeState> mTeeState;
TeeBranch mBranch;
};
NS_IMPL_CYCLE_COLLECTION_INHERITED(ByteStreamTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase, mTeeState)
NS_IMPL_ADDREF_INHERITED(ByteStreamTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase)
NS_IMPL_RELEASE_INHERITED(ByteStreamTeeSourceAlgorithms,
UnderlyingSourceAlgorithmsBase)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ByteStreamTeeSourceAlgorithms)
NS_INTERFACE_MAP_END_INHERITING(UnderlyingSourceAlgorithmsBase)
struct PullWithDefaultReaderReadRequest final : public ReadRequest {
RefPtr<TeeState> mTeeState;
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(PullWithDefaultReaderReadRequest,
ReadRequest)
explicit PullWithDefaultReaderReadRequest(TeeState* aTeeState)
: mTeeState(aTeeState) {}
void ChunkSteps(JSContext* aCx, JS::Handle<JS::Value> aChunk,
ErrorResult& aRv) override {
// Step 15.2.1
class PullWithDefaultReaderChunkStepMicrotask : public MicroTaskRunnable {
RefPtr<TeeState> mTeeState;
JS::PersistentRooted<JSObject*> mChunk;
public:
PullWithDefaultReaderChunkStepMicrotask(JSContext* aCx,
TeeState* aTeeState,
JS::Handle<JSObject*> aChunk)
: mTeeState(aTeeState), mChunk(aCx, aChunk) {}
MOZ_CAN_RUN_SCRIPT
void Run(AutoSlowOperation& aAso) override {
// Step Numbering in this function is relative to the Queue a microtask
// of the Chunk steps of 15.2.1 of
AutoJSAPI jsapi;
if (NS_WARN_IF(
!jsapi.Init(mTeeState->GetStream()->GetParentObject()))) {
return;
}
JSContext* cx = jsapi.cx();
// Step 1. Set readAgainForBranch1 to false.
mTeeState->SetReadAgainForBranch1(false);
// Step 2. Set readAgainForBranch2 to false.
mTeeState->SetReadAgainForBranch2(false);
// Step 3. Let chunk1 and chunk2 be chunk.
JS::Rooted<JSObject*> chunk1(cx, mChunk);
JS::Rooted<JSObject*> chunk2(cx, mChunk);
// Step 4. If canceled1 is false and canceled2 is false,
ErrorResult rv;
if (!mTeeState->Canceled1() && !mTeeState->Canceled2()) {
// Step 4.1. Let cloneResult be CloneAsUint8Array(chunk).
JS::Rooted<JSObject*> cloneResult(cx, CloneAsUint8Array(cx, mChunk));
// Step 4.2. If cloneResult is an abrupt completion,
if (!cloneResult) {
// Step 4.2.1 Perform
// !ReadableByteStreamControllerError(branch1.[[controller]],
// cloneResult.[[Value]]).
JS::Rooted<JS::Value> exceptionValue(cx);
if (!JS_GetPendingException(cx, &exceptionValue)) {
// Uncatchable exception, simply return.
return;
}
JS_ClearPendingException(cx);
ErrorResult rv;
ReadableByteStreamControllerError(
mTeeState->Branch1()->Controller()->AsByte(), exceptionValue,
rv);
if (rv.MaybeSetPendingException(
cx, "Error during ReadableByteStreamControllerError")) {
return;
}
// Step 4.2.2. Perform !
// ReadableByteStreamControllerError(branch2.[[controller]],
// cloneResult.[[Value]]).
ReadableByteStreamControllerError(
mTeeState->Branch2()->Controller()->AsByte(), exceptionValue,
rv);
if (rv.MaybeSetPendingException(
cx, "Error during ReadableByteStreamControllerError")) {
return;
}
// Step 4.2.3. Resolve cancelPromise with !
// ReadableStreamCancel(stream, cloneResult.[[Value]]).
RefPtr<ReadableStream> stream(mTeeState->GetStream());
RefPtr<Promise> promise =
ReadableStreamCancel(cx, stream, exceptionValue, rv);
if (rv.MaybeSetPendingException(
cx, "Error during ReadableByteStreamControllerError")) {
return;
}
mTeeState->CancelPromise()->MaybeResolve(promise);
// Step 4.2.4. Return.
return;
}
// Step 4.3. Otherwise, set chunk2 to cloneResult.[[Value]].
chunk2 = cloneResult;
}
// Step 5. If canceled1 is false,
// perform ! ReadableByteStreamControllerEnqueue(branch1.[[controller]],
// chunk1).
if (!mTeeState->Canceled1()) {
ErrorResult rv;
RefPtr<ReadableByteStreamController> controller(
mTeeState->Branch1()->Controller()->AsByte());
ReadableByteStreamControllerEnqueue(cx, controller, chunk1, rv);
if (rv.MaybeSetPendingException(
cx, "Error during ReadableByteStreamControllerEnqueue")) {
return;
}
}
// Step 6. If canceled2 is false,
// perform ! ReadableByteStreamControllerEnqueue(branch2.[[controller]],
// chunk2).
if (!mTeeState->Canceled2()) {
ErrorResult rv;
RefPtr<ReadableByteStreamController> controller(
mTeeState->Branch2()->Controller()->AsByte());
ReadableByteStreamControllerEnqueue(cx, controller, chunk2, rv);
if (rv.MaybeSetPendingException(
cx, "Error during ReadableByteStreamControllerEnqueue")) {
return;
}
}
// Step 7. Set reading to false.
mTeeState->SetReading(false);
// Step 8. If readAgainForBranch1 is true, perform pull1Algorithm.
if (mTeeState->ReadAgainForBranch1()) {
ByteStreamTeePullAlgorithm(cx, TeeBranch::Branch1,
MOZ_KnownLive(mTeeState), rv);
} else if (mTeeState->ReadAgainForBranch2()) {
// Step 9. Otherwise, if readAgainForBranch2 is true, perform
// pull2Algorithm.
ByteStreamTeePullAlgorithm(cx, TeeBranch::Branch2,
MOZ_KnownLive(mTeeState), rv);
}
}
bool Suppressed() override {
nsIGlobalObject* global = mTeeState->GetStream()->GetParentObject();
return global && global->IsInSyncOperation();
}
};
MOZ_ASSERT(aChunk.isObjectOrNull());
MOZ_ASSERT(aChunk.toObjectOrNull() != nullptr);
JS::Rooted<JSObject*> chunk(aCx, &aChunk.toObject());
RefPtr<PullWithDefaultReaderChunkStepMicrotask> task =
MakeRefPtr<PullWithDefaultReaderChunkStepMicrotask>(aCx, mTeeState,
chunk);
CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
}
MOZ_CAN_RUN_SCRIPT void CloseSteps(JSContext* aCx,
ErrorResult& aRv) override {
// Step numbering below is relative to Step 15.2. 'close steps' of
// Step 1. Set reading to false.
mTeeState->SetReading(false);
// Step 2. If canceled1 is false, perform !
// ReadableByteStreamControllerClose(branch1.[[controller]]).
RefPtr<ReadableByteStreamController> branch1Controller =
mTeeState->Branch1()->Controller()->AsByte();
if (!mTeeState->Canceled1()) {
ReadableByteStreamControllerClose(aCx, branch1Controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 3. If canceled2 is false, perform !
// ReadableByteStreamControllerClose(branch2.[[controller]]).
RefPtr<ReadableByteStreamController> branch2Controller =
mTeeState->Branch2()->Controller()->AsByte();
if (!mTeeState->Canceled2()) {
ReadableByteStreamControllerClose(aCx, branch2Controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 4. If branch1.[[controller]].[[pendingPullIntos]] is not empty,
// perform ! ReadableByteStreamControllerRespond(branch1.[[controller]], 0).
if (!branch1Controller->PendingPullIntos().isEmpty()) {
ReadableByteStreamControllerRespond(aCx, branch1Controller, 0, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 5. If branch2.[[controller]].[[pendingPullIntos]] is not empty,
// perform ! ReadableByteStreamControllerRespond(branch2.[[controller]], 0).
if (!branch2Controller->PendingPullIntos().isEmpty()) {
ReadableByteStreamControllerRespond(aCx, branch2Controller, 0, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 6. If canceled1 is false or canceled2 is false, resolve
// cancelPromise with undefined.
if (!mTeeState->Canceled1() || !mTeeState->Canceled2()) {
mTeeState->CancelPromise()->MaybeResolveWithUndefined();
}
}
void ErrorSteps(JSContext* aCx, JS::Handle<JS::Value> aError,
ErrorResult& aRv) override {
mTeeState->SetReading(false);
}
protected:
~PullWithDefaultReaderReadRequest() override = default;
};
NS_IMPL_CYCLE_COLLECTION_INHERITED(PullWithDefaultReaderReadRequest,
ReadRequest, mTeeState)
NS_IMPL_ADDREF_INHERITED(PullWithDefaultReaderReadRequest, ReadRequest)
NS_IMPL_RELEASE_INHERITED(PullWithDefaultReaderReadRequest, ReadRequest)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PullWithDefaultReaderReadRequest)
NS_INTERFACE_MAP_END_INHERITING(ReadRequest)
void ForwardReaderError(TeeState* aTeeState,
ReadableStreamGenericReader* aThisReader);
// Step 15.
void PullWithDefaultReader(JSContext* aCx, TeeState* aTeeState,
ErrorResult& aRv) {
RefPtr<ReadableStreamGenericReader> reader = aTeeState->GetReader();
// Step 15.1. If reader implements ReadableStreamBYOBReader,
if (reader->IsBYOB()) {
// Step 15.1.1. Assert: reader.[[readIntoRequests]] is empty.
MOZ_ASSERT(reader->AsBYOB()->ReadIntoRequests().length() == 0);
// Step 15.1.2. Perform ! ReadableStreamBYOBReaderRelease(reader).
ReadableStreamBYOBReaderRelease(aCx, reader->AsBYOB(), aRv);
if (aRv.Failed()) {
return;
}
// Step 15.1.3. Set reader to ! AcquireReadableStreamDefaultReader(stream).
reader = AcquireReadableStreamDefaultReader(aTeeState->GetStream(), aRv);
if (aRv.Failed()) {
return;
}
aTeeState->SetReader(reader);
// Step 16.1.4. Perform forwardReaderError, given reader.
ForwardReaderError(aTeeState, reader);
}
// Step 15.2
RefPtr<ReadRequest> readRequest =
new PullWithDefaultReaderReadRequest(aTeeState);
// Step 15.3
ReadableStreamDefaultReaderRead(aCx, reader, readRequest, aRv);
}
class PullWithBYOBReader_ReadIntoRequest final : public ReadIntoRequest {
RefPtr<TeeState> mTeeState;
const TeeBranch mForBranch;
~PullWithBYOBReader_ReadIntoRequest() override = default;
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(PullWithBYOBReader_ReadIntoRequest,
ReadIntoRequest)
explicit PullWithBYOBReader_ReadIntoRequest(TeeState* aTeeState,
TeeBranch aForBranch)
: mTeeState(aTeeState), mForBranch(aForBranch) {}
void ChunkSteps(JSContext* aCx, JS::Handle<JS::Value> aChunk,
ErrorResult& aRv) override {
// Step 16.4 chunk steps, Step 1.
class PullWithBYOBReaderChunkMicrotask : public MicroTaskRunnable {
RefPtr<TeeState> mTeeState;
JS::PersistentRooted<JSObject*> mChunk;
const TeeBranch mForBranch;
public:
PullWithBYOBReaderChunkMicrotask(JSContext* aCx, TeeState* aTeeState,
JS::Handle<JSObject*> aChunk,
TeeBranch aForBranch)
: mTeeState(aTeeState), mChunk(aCx, aChunk), mForBranch(aForBranch) {}
MOZ_CAN_RUN_SCRIPT
void Run(AutoSlowOperation& aAso) override {
AutoJSAPI jsapi;
if (NS_WARN_IF(
!jsapi.Init(mTeeState->GetStream()->GetParentObject()))) {
return;
}
JSContext* cx = jsapi.cx();
ErrorResult rv;
//
// Step Numbering below is relative to Chunk steps Microtask at
// Step 16.4 chunk steps, Step 1.
// Step 1.
mTeeState->SetReadAgainForBranch1(false);
// Step 2.
mTeeState->SetReadAgainForBranch2(false);
// Step 3.
bool byobCanceled = mTeeState->Canceled(mForBranch);
// Step 4.
bool otherCanceled = mTeeState->Canceled(OtherTeeBranch(mForBranch));
// Rather than store byobBranch / otherBranch, we re-derive the pointers
// below, as borrowed from steps 16.2/16.3
ReadableStream* byobBranch = mTeeState->Branch(mForBranch);
ReadableStream* otherBranch =
mTeeState->Branch(OtherTeeBranch(mForBranch));
// Step 5.
if (!otherCanceled) {
// Step 5.1 (using the name clonedChunk because we don't want to name
// the completion record explicitly)
JS::Rooted<JSObject*> clonedChunk(cx, CloneAsUint8Array(cx, mChunk));
// Step 5.2. If cloneResult is an abrupt completion,
if (!clonedChunk) {
JS::Rooted<JS::Value> exception(cx);
if (!JS_GetPendingException(cx, &exception)) {
// Uncatchable exception. Return with pending
// exception still on context.
return;
}
// It's not expliclitly stated, but I assume the intention here is
// that we perform a normal completion here, so we clear the
// exception.
JS_ClearPendingException(cx);
// Step 5.2.1
ReadableByteStreamControllerError(
byobBranch->Controller()->AsByte(), exception, rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
// Step 5.2.2.
ReadableByteStreamControllerError(
otherBranch->Controller()->AsByte(), exception, rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
// Step 5.2.3.
RefPtr<ReadableStream> stream = mTeeState->GetStream();
RefPtr<Promise> cancelPromise =
ReadableStreamCancel(cx, stream, exception, rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
mTeeState->CancelPromise()->MaybeResolve(cancelPromise);
// Step 5.2.4.
return;
}
// Step 5.3 (implicitly handled above by name selection)
// Step 5.4.
if (!byobCanceled) {
RefPtr<ReadableByteStreamController> controller(
byobBranch->Controller()->AsByte());
ReadableByteStreamControllerRespondWithNewView(cx, controller,
mChunk, rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
}
// Step 5.4.
RefPtr<ReadableByteStreamController> otherController =
otherBranch->Controller()->AsByte();
ReadableByteStreamControllerEnqueue(cx, otherController, clonedChunk,
rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
// Step 6.
} else if (!byobCanceled) {
RefPtr<ReadableByteStreamController> byobController =
byobBranch->Controller()->AsByte();
ReadableByteStreamControllerRespondWithNewView(cx, byobController,
mChunk, rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
}
// Step 7.
mTeeState->SetReading(false);
// Step 8.
if (mTeeState->ReadAgainForBranch1()) {
ByteStreamTeePullAlgorithm(cx, TeeBranch::Branch1,
MOZ_KnownLive(mTeeState), rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
} else if (mTeeState->ReadAgainForBranch2()) {
ByteStreamTeePullAlgorithm(cx, TeeBranch::Branch2,
MOZ_KnownLive(mTeeState), rv);
if (rv.MaybeSetPendingException(cx)) {
return;
}
}
}
bool Suppressed() override {
nsIGlobalObject* global = mTeeState->GetStream()->GetParentObject();
return global && global->IsInSyncOperation();
}
};
MOZ_ASSERT(aChunk.isObjectOrNull());
MOZ_ASSERT(aChunk.toObjectOrNull());
JS::Rooted<JSObject*> chunk(aCx, aChunk.toObjectOrNull());
RefPtr<PullWithBYOBReaderChunkMicrotask> task =
MakeRefPtr<PullWithBYOBReaderChunkMicrotask>(aCx, mTeeState, chunk,
mForBranch);
CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
}
MOZ_CAN_RUN_SCRIPT
void CloseSteps(JSContext* aCx, JS::Handle<JS::Value> aChunk,
ErrorResult& aRv) override {
// Step 1.
mTeeState->SetReading(false);
// Step 2.
bool byobCanceled = mTeeState->Canceled(mForBranch);
// Step 3.
bool otherCanceled = mTeeState->Canceled(OtherTeeBranch(mForBranch));
// Rather than store byobBranch / otherBranch, we re-derive the pointers
// below, as borrowed from steps 16.2/16.3
ReadableStream* byobBranch = mTeeState->Branch(mForBranch);
ReadableStream* otherBranch = mTeeState->Branch(OtherTeeBranch(mForBranch));
// Step 4.
if (!byobCanceled) {
RefPtr<ReadableByteStreamController> controller =
byobBranch->Controller()->AsByte();
ReadableByteStreamControllerClose(aCx, controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 5.
if (!otherCanceled) {
RefPtr<ReadableByteStreamController> controller =
otherBranch->Controller()->AsByte();
ReadableByteStreamControllerClose(aCx, controller, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 6.
if (!aChunk.isUndefined()) {
MOZ_ASSERT(aChunk.isObject());
MOZ_ASSERT(aChunk.toObjectOrNull());
JS::Rooted<JSObject*> chunkObject(aCx, &aChunk.toObject());
MOZ_ASSERT(JS_IsArrayBufferViewObject(chunkObject));
// Step 6.1.
MOZ_ASSERT(JS_GetArrayBufferViewByteLength(chunkObject) == 0);
// Step 6.2.
if (!byobCanceled) {
RefPtr<ReadableByteStreamController> byobController(
byobBranch->Controller()->AsByte());
ReadableByteStreamControllerRespondWithNewView(aCx, byobController,
chunkObject, aRv);
if (aRv.Failed()) {
return;
}
}
// Step 6.3
if (!otherCanceled &&
!otherBranch->Controller()->AsByte()->PendingPullIntos().isEmpty()) {
RefPtr<ReadableByteStreamController> otherController(
otherBranch->Controller()->AsByte());
ReadableByteStreamControllerRespond(aCx, otherController, 0, aRv);
if (aRv.Failed()) {
return;
}
}
}
// Step 7.
if (!byobCanceled || !otherCanceled) {
mTeeState->CancelPromise()->MaybeResolveWithUndefined();
}
}
void ErrorSteps(JSContext* aCx, JS::Handle<JS::Value> e,
ErrorResult& aRv) override {
// Step 1.
mTeeState->SetReading(false);
}
};
NS_IMPL_CYCLE_COLLECTION_INHERITED(PullWithBYOBReader_ReadIntoRequest,
ReadIntoRequest, mTeeState)
NS_IMPL_ADDREF_INHERITED(PullWithBYOBReader_ReadIntoRequest, ReadIntoRequest)
NS_IMPL_RELEASE_INHERITED(PullWithBYOBReader_ReadIntoRequest, ReadIntoRequest)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PullWithBYOBReader_ReadIntoRequest)
NS_INTERFACE_MAP_END_INHERITING(ReadIntoRequest)
// Step 16.
void PullWithBYOBReader(JSContext* aCx, TeeState* aTeeState,
JS::Handle<JSObject*> aView, TeeBranch aForBranch,
ErrorResult& aRv) {
// Step 16.1
if (aTeeState->GetReader()->IsDefault()) {
// Step 16.1.1
MOZ_ASSERT(aTeeState->GetDefaultReader()->ReadRequests().isEmpty());
// Step 16.1.2. Perform ! ReadableStreamDefaultReaderRelease(reader).
ReadableStreamDefaultReaderRelease(aCx, aTeeState->GetDefaultReader(), aRv);
if (aRv.Failed()) {
return;
}
// Step 16.1.3. Set reader to !AcquireReadableStreamBYOBReader(stream).
RefPtr<ReadableStreamBYOBReader> reader =
AcquireReadableStreamBYOBReader(aTeeState->GetStream(), aRv);
if (aRv.Failed()) {
return;
}
aTeeState->SetReader(reader);
// Step 16.1.4. Perform forwardReaderError, given reader.
ForwardReaderError(aTeeState, reader);
}
// Step 16.2. Unused in this function, moved to consumers.
// Step 16.3. Unused in this function, moved to consumers.
// Step 16.4.
RefPtr<ReadIntoRequest> readIntoRequest =
new PullWithBYOBReader_ReadIntoRequest(aTeeState, aForBranch);
// Step 16.5. Perform ! ReadableStreamBYOBReaderRead(reader, view, 1,
// readIntoRequest).
RefPtr<ReadableStreamBYOBReader> byobReader =
aTeeState->GetReader()->AsBYOB();
ReadableStreamBYOBReaderRead(aCx, byobReader, aView, 1, readIntoRequest, aRv);
}
// Step 14.
void ForwardReaderError(TeeState* aTeeState,
ReadableStreamGenericReader* aThisReader) {
aThisReader->ClosedPromise()->AddCallbacksWithCycleCollectedArgs(
[](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
TeeState* aTeeState, ReadableStreamGenericReader* aThisReader) {},
[](JSContext* aCx, JS::Handle<JS::Value> aValue, ErrorResult& aRv,
TeeState* aTeeState, ReadableStreamGenericReader* aReader) {
// Step 14.1.1
if (aTeeState->GetReader() != aReader) {
return;
}
ErrorResult rv;
// Step 14.1.2: Perform
// !ReadableByteStreamControllerError(branch1.[[controller]], r).
MOZ_ASSERT(aTeeState->Branch1()->Controller()->IsByte());
ReadableByteStreamControllerError(
aTeeState->Branch1()->Controller()->AsByte(), aValue, aRv);
if (aRv.Failed()) {
return;
}
// Step 14.1.3: Perform
// !ReadableByteStreamControllerError(branch2.[[controller]], r).
MOZ_ASSERT(aTeeState->Branch2()->Controller()->IsByte());
ReadableByteStreamControllerError(
aTeeState->Branch2()->Controller()->AsByte(), aValue, aRv);
if (aRv.Failed()) {
return;
}
// Step 14.1.4: If canceled1 is false or canceled2 is false, resolve
// cancelPromise with undefined.
if (!aTeeState->Canceled1() || !aTeeState->Canceled2()) {
aTeeState->CancelPromise()->MaybeResolveWithUndefined();
}
},
RefPtr(aTeeState), RefPtr(aThisReader));
}
namespace streams_abstract {
void ReadableByteStreamTee(JSContext* aCx, ReadableStream* aStream,
nsTArray<RefPtr<ReadableStream>>& aResult,
ErrorResult& aRv) {
// Step 1. Implicit
// Step 2.
MOZ_ASSERT(aStream->Controller()->IsByte());
// Step 3-13 captured as part of TeeState allocation
RefPtr<TeeState> teeState = TeeState::Create(aStream, false, aRv);
if (aRv.Failed()) {
return;
}
// Step 14: See ForwardReaderError
// Step 15. See PullWithDefaultReader
// Step 16. See PullWithBYOBReader
// Step 17,18. See {Native,}ByteStreamTeePullAlgorithm
// Step 19,20. See ReadableByteStreamTeeCancelAlgorithm
// Step 21. Elided because consumers know how to handle nullptr correctly.
// Step 22.
nsCOMPtr<nsIGlobalObject> global = aStream->GetParentObject();
auto branch1Algorithms =
MakeRefPtr<ByteStreamTeeSourceAlgorithms>(teeState, TeeBranch::Branch1);
teeState->SetBranch1(
ReadableStream::CreateByteAbstract(aCx, global, branch1Algorithms, aRv));
if (aRv.Failed()) {
return;
}
// Step 23.
auto branch2Algorithms =
MakeRefPtr<ByteStreamTeeSourceAlgorithms>(teeState, TeeBranch::Branch2);
teeState->SetBranch2(
ReadableStream::CreateByteAbstract(aCx, global, branch2Algorithms, aRv));
if (aRv.Failed()) {
return;
}
// Step 24.
ForwardReaderError(teeState, teeState->GetReader());
// Step 25.
aResult.AppendElement(teeState->Branch1());
aResult.AppendElement(teeState->Branch2());
}
} // namespace streams_abstract
} // namespace mozilla::dom