MIDIPort.h - mozsearch

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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/. */

#ifndef mozilla_dom_MIDIPort_h

#define mozilla_dom_MIDIPort_h

#include "mozilla/DOMEventTargetHelper.h"

#include "mozilla/dom/MIDIAccess.h"

#include "mozilla/dom/MIDIPortChild.h"

#include "mozilla/dom/MIDIPortInterface.h"

struct JSContext;

namespace mozilla::dom {

class Promise;

class MIDIPortInfo;

class MIDIAccess;

class MIDIPortChangeEvent;

class MIDIPortChild;

class MIDIMessage;

/**

 * Implementation of WebIDL DOM MIDIPort class. Handles all port representation

 * and communication.

*/

class MIDIPort : public DOMEventTargetHelper {

 public:

  NS_DECL_ISUPPORTS_INHERITED

  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(MIDIPort,

                                                         DOMEventTargetHelper)

 protected:

  explicit MIDIPort(nsPIDOMWindowInner* aWindow);

  bool Initialize(const MIDIPortInfo& aPortInfo, bool aSysexEnabled,

                  MIDIAccess* aMIDIAccessParent);

  virtual ~MIDIPort();

 public:

  nsIGlobalObject* GetParentObject() const { return GetOwnerGlobal(); }

  // Getters

  void GetId(nsString& aRetVal) const;

  void GetManufacturer(nsString& aRetVal) const;

  void GetName(nsString& aRetVal) const;

  void GetVersion(nsString& aRetVal) const;

  MIDIPortType Type() const;

  MIDIPortConnectionState Connection() const;

  MIDIPortDeviceState State() const;

  bool SysexEnabled() const;

  already_AddRefed<Promise> Open(ErrorResult& aError);

  already_AddRefed<Promise> Close(ErrorResult& aError);

  void FireStateChangeEvent();

  virtual void StateChange();

  virtual void Receive(const nsTArray<MIDIMessage>& aMsg);

  // This object holds a pointer to its corresponding IPC MIDIPortChild actor.

  // If the IPC actor is deleted, it cleans itself up via this method.

  void UnsetIPCPort();

  IMPL_EVENT_HANDLER(statechange)

  void DisconnectFromOwner() override;

  const nsString& StableId();

 protected:

  // Helper class to ensure we always call DetachOwner when we drop the

  // reference to the the port.

  class PortHolder {

   public:

    void Init(already_AddRefed<MIDIPortChild> aArg) {

      MOZ_ASSERT(!mInner);

      mInner = aArg;

    void Clear() {

      if (mInner) {

        mInner->DetachOwner();

        mInner = nullptr;

    ~PortHolder() { Clear(); }

    MIDIPortChild* Get() const { return mInner; }

   private:

    RefPtr<MIDIPortChild> mInner;

};

  // IPC Actor corresponding to this class.

  PortHolder mPortHolder;

  MIDIPortChild* Port() const { return mPortHolder.Get(); }

 private:

  void KeepAliveOnStatechange();

  void DontKeepAliveOnStatechange();

  // MIDIAccess object that created this MIDIPort object, which we need for

  // firing port connection events. There is a chance this MIDIPort object can

  // outlive its parent MIDIAccess object, so this is a weak pointer.

  WeakPtr<MIDIAccess> mMIDIAccessParent;

  // Promise object generated on Open() call, that needs to be resolved once the

  // platform specific Open() function has completed.

  RefPtr<Promise> mOpeningPromise;

  // Promise object generated on Close() call, that needs to be resolved once

  // the platform specific Close() function has completed.

  RefPtr<Promise> mClosingPromise;

  // If true this object will be kept alive even without direct JS references

  bool mKeepAlive;

};

}  // namespace mozilla::dom

#endif  // mozilla_dom_MIDIPort_h