Source code

Revision control

Other Tools

/* -*- 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 */
#ifndef mozilla_dom_MIDIAccess_h
#define mozilla_dom_MIDIAccess_h
#include "mozilla/Attributes.h"
#include "mozilla/DOMEventTargetHelper.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/Observer.h"
#include "nsCycleCollectionParticipant.h"
#include "nsWrapperCache.h"
struct JSContext;
namespace mozilla {
// Predeclare void_t here, as including IPCMessageUtils brings in windows.h and
// causes binding compilation problems.
struct void_t;
namespace dom {
class MIDIAccessManager;
class MIDIInputMap;
struct MIDIOptions;
class MIDIOutputMap;
class MIDIPermissionRequest;
class MIDIPort;
class MIDIPortChangeEvent;
class MIDIPortInfo;
class MIDIPortList;
class Promise;
typedef Observer<void_t> MIDIAccessDestructionObserver;
* MIDIAccess is the DOM object that is handed to the user upon MIDI permissions
* being successfully granted. It manages access to MIDI ports, and fires events
* for device connection and disconnection.
* New MIDIAccess objects are created every time RequestMIDIAccess is called.
* MIDIAccess objects are managed via MIDIAccessManager.
class MIDIAccess final : public DOMEventTargetHelper,
public Observer<MIDIPortList> {
// Use the Permission Request class in MIDIAccessManager for creating
// MIDIAccess objects.
friend class MIDIPermissionRequest;
friend class MIDIAccessManager;
virtual JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) override;
// Return map of MIDI Input Ports
MIDIInputMap* Inputs() const { return mInputMap; }
// Return map of MIDI Output Ports
MIDIOutputMap* Outputs() const { return mOutputMap; }
// Returns true if sysex permissions were given
bool SysexEnabled() const { return mSysexEnabled; }
// Observer implementation for receiving port connection updates
void Notify(const MIDIPortList& aEvent) override;
// All MIDIPort objects observe destruction of the MIDIAccess object that
// created them, as the port object receives disconnection events which then
// must be passed up to the MIDIAccess object. If the Port object dies before
// the MIDIAccess object, it needs to be removed from the observer list.
void RemovePortListener(MIDIAccessDestructionObserver* aPort);
// Fires DOM event on port connection/disconnection
void FireConnectionEvent(MIDIPort* aPort);
// Notify all MIDIPorts that were created by this MIDIAccess and are still
// alive, and detach from the MIDIAccessManager.
void Shutdown();
MIDIAccess(nsPIDOMWindowInner* aWindow, bool aSysexEnabled,
Promise* aAccessPromise);
// On receiving a connection event from MIDIAccessManager, create a
// corresponding MIDIPort object if we don't already have one.
void MaybeCreateMIDIPort(const MIDIPortInfo& aInfo, ErrorResult& aRv);
// Stores all known MIDIInput Ports
RefPtr<MIDIInputMap> mInputMap;
// Stores all known MIDIOutput Ports
RefPtr<MIDIOutputMap> mOutputMap;
// List of MIDIPort observers that need to be updated on destruction.
ObserverList<void_t> mDestructionObservers;
// True if user gave permissions for sysex usage to this object.
bool mSysexEnabled;
// Promise created by RequestMIDIAccess call, to be resolved after port
// populating is finished.
RefPtr<Promise> mAccessPromise;
// True if shutdown process has started, so we don't try to add more ports.
bool mHasShutdown;
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_MIDIAccess_h