dom/midi/MIDIPlatformService.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_MIDIPlatformService_h
   8 #define mozilla_dom_MIDIPlatformService_h
   9
  10 #include "nsClassHashtable.h"
  11 #include "mozilla/Mutex.h"
  12 #include "mozilla/dom/MIDIPortBinding.h"
  13 #include "nsHashKeys.h"
  14
  15 // XXX Avoid including this here by moving function implementations to the cpp
  16 // file.
  17 #include "mozilla/dom/MIDIMessageQueue.h"
  18
  19 namespace mozilla::dom {
  20
  21 class MIDIManagerParent;
  22 class MIDIPortParent;
  23 class MIDIMessage;
  24 class MIDIMessageQueue;
  25 class MIDIPortInfo;
  26
  27 /**
  28  * Base class for platform specific MIDI implementations. Handles aggregation of
  29  * IPC service objects, as well as sending/receiving updates about port
  30  * connection events and messages.
  31  *
  32  */
  33 class MIDIPlatformService {
  34  public:
  35   NS_INLINE_DECL_REFCOUNTING(MIDIPlatformService);
  36   // Adds info about MIDI Port that has been connected.
  37   void AddPortInfo(MIDIPortInfo& aPortInfo);
  38
  39   // Removes info of MIDI Port that has been disconnected.
  40   void RemovePortInfo(MIDIPortInfo& aPortInfo);
  41
  42   // Adds a newly created manager protocol object to manager array.
  43   void AddManager(MIDIManagerParent* aManager);
  44
  45   // Removes a deleted manager protocol object from manager array.
  46   void RemoveManager(MIDIManagerParent* aManager);
  47
  48   // Adds a newly created port protocol object to port array.
  49   void AddPort(MIDIPortParent* aPort);
  50
  51   // Removes a deleted port protocol object from port array.
  52   void RemovePort(MIDIPortParent* aPort);
  53
  54   // Platform specific init function.
  55   virtual void Init() = 0;
  56
  57   // Platform specific MIDI port opening function.
  58   virtual void Open(MIDIPortParent* aPort) = 0;
  59
  60   // Clears all queued MIDI messages for a port.
  61   void Clear(MIDIPortParent* aPort);
  62
  63   // Puts in a request to destroy the singleton MIDIPlatformService object.
  64   // Object will only be destroyed if there are no more MIDIManager and MIDIPort
  65   // protocols left to communicate with.
  66   void MaybeStop();
  67
  68   // True if service is live.
  69   static bool IsRunning();
  70
  71   // Returns a pointer to the MIDIPlatformService object, creating it and
  72   // starting the platform specific service if it is not currently running.
  73   static MIDIPlatformService* Get();
  74
  75   // Sends a list of all currently connected ports in order to populate a new
  76   // MIDIAccess object.
  77   void SendPortList();
  78
  79   // Receives a new set of messages from an MIDI Input Port, and checks their
  80   // validity.
  81   void CheckAndReceive(const nsAString& aPortID,
  82                        const nsTArray<MIDIMessage>& aMsgs);
  83
  84   // Sends connection/disconnect/open/closed/etc status updates about a MIDI
  85   // Port to all port listeners.
  86   void UpdateStatus(MIDIPortParent* aPort,
  87                     const MIDIPortDeviceState& aDeviceState,
  88                     const MIDIPortConnectionState& aConnectionState);
  89
  90   // Adds outgoing messages to the sorted message queue, for sending later.
  91   void QueueMessages(const nsAString& aId, nsTArray<MIDIMessage>& aMsgs);
  92
  93   // Clears all messages later than now, sends all outgoing message scheduled
  94   // before/at now, and schedules MIDI Port connection closing.
  95   void Close(MIDIPortParent* aPort);
  96
  97  protected:
  98   MIDIPlatformService();
  99   virtual ~MIDIPlatformService();
 100   // Platform specific MIDI service shutdown method.
 101   virtual void Stop() = 0;
 102
 103   // When device state of a MIDI Port changes, broadcast to all IPC port
 104   // objects.
 105   void BroadcastState(const MIDIPortInfo& aPortInfo,
 106                       const MIDIPortDeviceState& aState);
 107
 108   // Platform specific MIDI port closing function. Named "Schedule" due to the
 109   // fact that it needs to happen in the context of the I/O thread for the
 110   // platform MIDI implementation, and therefore will happen async.
 111   virtual void ScheduleClose(MIDIPortParent* aPort) = 0;
 112
 113   // Platform specific MIDI message sending function. Named "Schedule" due to
 114   // the fact that it needs to happen in the context of the I/O thread for the
 115   // platform MIDI implementation, and therefore will happen async.
 116   virtual void ScheduleSend(const nsAString& aPortId) = 0;
 117
 118   // Allows platform specific IO Threads to retrieve all messages to be sent.
 119   // Handles mutex locking.
 120   void GetMessages(const nsAString& aPortId, nsTArray<MIDIMessage>& aMsgs);
 121
 122   // Allows platform specific IO Threads to retrieve all messages to be sent
 123   // before a certain timestamp. Handles mutex locking.
 124   void GetMessagesBefore(const nsAString& aPortId, const TimeStamp& aTimeStamp,
 125                          nsTArray<MIDIMessage>& aMsgs);
 126
 127  private:
 128   // When the MIDIPlatformService is created, we need to know whether or not the
 129   // corresponding IPC MIDIManager objects have received the MIDIPort list after
 130   // it is populated. This is set to True when that is done, so we don't
 131   // constantly spam MIDIManagers with port lists.
 132   bool mHasSentPortList;
 133
 134   // Array of MIDIManager IPC objects. This array manages the lifetime of
 135   // MIDIManager objects in the parent process, and IPC will call
 136   // RemoveManager() end lifetime when IPC channel is destroyed.
 137   nsTArray<RefPtr<MIDIManagerParent>> mManagers;
 138
 139   // Array of information for currently connected Ports
 140   nsTArray<MIDIPortInfo> mPortInfo;
 141
 142   // Array of MIDIPort IPC objects. May contain ports not listed in mPortInfo,
 143   // as we can hold port objects even after they are disconnected.
 144   //
 145   // TODO Split this into input and output ports. Will make life easier.
 146   nsTArray<RefPtr<MIDIPortParent>> mPorts;
 147
 148   // Per-port message queue hashtable. Handles scheduling messages for sending.
 149   nsClassHashtable<nsStringHashKey, MIDIMessageQueue> mMessageQueues;
 150
 151   // Mutex for managing access to message queue objects.
 152   Mutex mMessageQueueMutex;
 153 };
 154
 155 }  // namespace mozilla::dom
 156
 157 #endif  // mozilla_dom_MIDIPlatformService_h