WritableStreamDefaultController.h

Enable keyboard shortcuts

/* -*- 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/. */

#ifndef mozilla_dom_WritableStreamDefaultController_h

#define mozilla_dom_WritableStreamDefaultController_h

#include "js/TypeDecls.h"

#include "mozilla/AlreadyAddRefed.h"

#include "mozilla/Attributes.h"

#include "mozilla/ErrorResult.h"

#include "mozilla/dom/BindingDeclarations.h"

#include "mozilla/dom/QueuingStrategyBinding.h"

#include "mozilla/dom/QueueWithSizes.h"

#include "mozilla/dom/ReadRequest.h"

#include "mozilla/dom/UnderlyingSinkCallbackHelpers.h"

#include "nsCycleCollectionParticipant.h"

#include "nsWrapperCache.h"

#include "mozilla/dom/Nullable.h"

#include "nsTArray.h"

#include "nsISupports.h"

namespace mozilla::dom {

class AbortSignal;

class WritableStream;

struct UnderlyingSink;

class WritableStreamDefaultController final : public nsISupports,

                                              public nsWrapperCache {

 public:

  NS_DECL_CYCLE_COLLECTING_ISUPPORTS

  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(WritableStreamDefaultController)

  explicit WritableStreamDefaultController(nsISupports* aGlobal,

                                           WritableStream& aStream);

 protected:

  ~WritableStreamDefaultController();

 public:

  nsIGlobalObject* GetParentObject() const { return mGlobal; }

  JSObject* WrapObject(JSContext* aCx,

                       JS::Handle<JSObject*> aGivenProto) override;

  // WebIDL methods/properties

  AbortSignal* Signal() { return mSignal; }

  MOZ_CAN_RUN_SCRIPT void Error(JSContext* aCx, JS::Handle<JS::Value> aError,

                                ErrorResult& aRv);

  // [[AbortSteps]]

  MOZ_CAN_RUN_SCRIPT virtual already_AddRefed<Promise> AbortSteps(

      JSContext* aCx, JS::Handle<JS::Value> aReason, ErrorResult& aRv);

  // [[ErrorSteps]]

  virtual void ErrorSteps();

  // Internal Slot Accessors

  QueueWithSizes& Queue() { return mQueue; }

  double QueueTotalSize() const { return mQueueTotalSize; }

  void SetQueueTotalSize(double aQueueTotalSize) {

    mQueueTotalSize = aQueueTotalSize;

  void SetSignal(AbortSignal* aSignal);

  bool Started() const { return mStarted; }

  void SetStarted(bool aStarted) { mStarted = aStarted; }

  double StrategyHWM() const { return mStrategyHWM; }

  void SetStrategyHWM(double aStrategyHWM) { mStrategyHWM = aStrategyHWM; }

  QueuingStrategySize* StrategySizeAlgorithm() const {

    return mStrategySizeAlgorithm;

  void SetStrategySizeAlgorithm(QueuingStrategySize* aStrategySizeAlgorithm) {

    mStrategySizeAlgorithm = aStrategySizeAlgorithm;

  UnderlyingSinkAlgorithmsBase* GetAlgorithms() { return mAlgorithms; }

  void SetAlgorithms(UnderlyingSinkAlgorithmsBase& aAlgorithms) {

    mAlgorithms = &aAlgorithms;

  WritableStream* Stream() { return mStream; }

  // WritableStreamDefaultControllerGetBackpressure

  // https://streams.spec.whatwg.org/#writable-stream-default-controller-get-backpressure

  bool GetBackpressure() const {

    // Step 1. Let desiredSize be !

    // WritableStreamDefaultControllerGetDesiredSize(controller).

    double desiredSize = GetDesiredSize();

    // Step 2. Return true if desiredSize ≤ 0, or false otherwise.

    return desiredSize <= 0;

  // WritableStreamDefaultControllerGetDesiredSize

  // https://streams.spec.whatwg.org/#writable-stream-default-controller-get-desired-size

  double GetDesiredSize() const { return mStrategyHWM - mQueueTotalSize; }

  // WritableStreamDefaultControllerClearAlgorithms

  // https://streams.spec.whatwg.org/#writable-stream-default-controller-clear-algorithms

  void ClearAlgorithms() {

    // Step 1. Set controller.[[writeAlgorithm]] to undefined.

    // Step 2. Set controller.[[closeAlgorithm]] to undefined.

    // Step 3. Set controller.[[abortAlgorithm]] to undefined.

    // (As written in the spec, this can happen multiple time. Try running

    // wpt/streams/transform-streams/errors.any.js for example.)

    if (RefPtr<UnderlyingSinkAlgorithmsBase> algorithms =

            mAlgorithms.forget()) {

      algorithms->ReleaseObjects();

    // Step 4. Set controller.[[strategySizeAlgorithm]] to undefined.

    mStrategySizeAlgorithm = nullptr;

 private:

  nsCOMPtr<nsIGlobalObject> mGlobal;

  // Internal Slots

  QueueWithSizes mQueue = {};

  double mQueueTotalSize = 0.0;

  RefPtr<AbortSignal> mSignal;

  bool mStarted = false;

  double mStrategyHWM = 0.0;

  RefPtr<QueuingStrategySize> mStrategySizeAlgorithm;

  RefPtr<UnderlyingSinkAlgorithmsBase> mAlgorithms;

  RefPtr<WritableStream> mStream;

};

namespace streams_abstract {

MOZ_CAN_RUN_SCRIPT void SetUpWritableStreamDefaultController(

    JSContext* aCx, WritableStream* aStream,

    WritableStreamDefaultController* aController,

    UnderlyingSinkAlgorithmsBase* aAlgorithms, double aHighWaterMark,

    QueuingStrategySize* aSizeAlgorithm, ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT void SetUpWritableStreamDefaultControllerFromUnderlyingSink(

    JSContext* aCx, WritableStream* aStream,

    JS::Handle<JSObject*> aUnderlyingSink, UnderlyingSink& aUnderlyingSinkDict,

    double aHighWaterMark, QueuingStrategySize* aSizeAlgorithm,

    ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT void WritableStreamDefaultControllerClose(

    JSContext* aCx, WritableStreamDefaultController* aController,

    ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT void WritableStreamDefaultControllerWrite(

    JSContext* aCx, WritableStreamDefaultController* aController,

    JS::Handle<JS::Value> aChunk, double chunkSize, ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT void WritableStreamDefaultControllerError(

    JSContext* aCx, WritableStreamDefaultController* aController,

    JS::Handle<JS::Value> aError, ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT void WritableStreamDefaultControllerErrorIfNeeded(

    JSContext* aCx, WritableStreamDefaultController* aController,

    JS::Handle<JS::Value> aError, ErrorResult& aRv);

MOZ_CAN_RUN_SCRIPT double WritableStreamDefaultControllerGetChunkSize(

    JSContext* aCx, WritableStreamDefaultController* aController,

    JS::Handle<JS::Value> aChunk, ErrorResult& aRv);

}  // namespace streams_abstract

}  // namespace mozilla::dom

#endif  // mozilla_dom_WritableStreamDefaultController_h