dom/midi/MIDIAccess.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_MIDIAccess_h
   8 #define mozilla_dom_MIDIAccess_h
   9
  10 #include "mozilla/Attributes.h"
  11 #include "mozilla/DOMEventTargetHelper.h"
  12 #include "mozilla/Observer.h"
  13 #include "mozilla/WeakPtr.h"
  14 #include "nsCycleCollectionParticipant.h"
  15 #include "nsWrapperCache.h"
  16
  17 struct JSContext;
  18
  19 namespace mozilla {
  20 class ErrorResult;
  21
  22 namespace dom {
  23
  24 class MIDIAccessManager;
  25 class MIDIInputMap;
  26 struct MIDIOptions;
  27 class MIDIOutputMap;
  28 class MIDIPermissionRequest;
  29 class MIDIPort;
  30 class MIDIPortChangeEvent;
  31 class MIDIPortInfo;
  32 class MIDIPortList;
  33 class Promise;
  34
  35 /**
  36  * MIDIAccess is the DOM object that is handed to the user upon MIDI permissions
  37  * being successfully granted. It manages access to MIDI ports, and fires events
  38  * for device connection and disconnection.
  39  *
  40  * New MIDIAccess objects are created every time RequestMIDIAccess is called.
  41  * MIDIAccess objects are managed via MIDIAccessManager.
  42  */
  43 class MIDIAccess final : public DOMEventTargetHelper,
  44                          public Observer<MIDIPortList> {
  45   // Use the Permission Request class in MIDIAccessManager for creating
  46   // MIDIAccess objects.
  47   friend class MIDIPermissionRequest;
  48   friend class MIDIAccessManager;
  49
  50  public:
  51   NS_DECL_ISUPPORTS_INHERITED
  52   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(MIDIAccess,
  53                                                          DOMEventTargetHelper)
  54  public:
  55   virtual JSObject* WrapObject(JSContext* aCx,
  56                                JS::Handle<JSObject*> aGivenProto) override;
  57
  58   // Return map of MIDI Input Ports
  59   MIDIInputMap* Inputs() const { return mInputMap; }
  60
  61   // Return map of MIDI Output Ports
  62   MIDIOutputMap* Outputs() const { return mOutputMap; }
  63
  64   // Returns true if sysex permissions were given
  65   bool SysexEnabled() const { return mSysexEnabled; }
  66
  67   // Observer implementation for receiving port connection updates
  68   void Notify(const MIDIPortList& aEvent) override;
  69
  70   // Fires DOM event on port connection/disconnection
  71   void FireConnectionEvent(MIDIPort* aPort);
  72
  73   // Notify all MIDIPorts that were created by this MIDIAccess and are still
  74   // alive, and detach from the MIDIAccessManager.
  75   void Shutdown();
  76   IMPL_EVENT_HANDLER(statechange);
  77
  78   void DisconnectFromOwner() override;
  79
  80  private:
  81   MIDIAccess(nsPIDOMWindowInner* aWindow, bool aSysexEnabled,
  82              Promise* aAccessPromise);
  83   ~MIDIAccess();
  84
  85   // On receiving a connection event from MIDIAccessManager, create a
  86   // corresponding MIDIPort object if we don't already have one.
  87   void MaybeCreateMIDIPort(const MIDIPortInfo& aInfo, ErrorResult& aRv);
  88
  89   // Stores all known MIDIInput Ports
  90   RefPtr<MIDIInputMap> mInputMap;
  91   // Stores all known MIDIOutput Ports
  92   RefPtr<MIDIOutputMap> mOutputMap;
  93   // True if user gave permissions for sysex usage to this object.
  94   bool mSysexEnabled;
  95   // Promise created by RequestMIDIAccess call, to be resolved after port
  96   // populating is finished.
  97   RefPtr<Promise> mAccessPromise;
  98   // True if shutdown process has started, so we don't try to add more ports.
  99   bool mHasShutdown;
 100 };
 101
 102 }  // namespace dom
 103 }  // namespace mozilla
 104
 105 #endif  // mozilla_dom_MIDIAccess_h