Web MIDI: introduce WebMIDIClient API to request a permission

Source/modules/webmidi/MIDIAccess.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 20 matching lines @@
 #include "config.h"
 #include "modules/webmidi/MIDIAccess.h"
 
 #include "core/dom/DOMError.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/loader/DocumentLoadTiming.h"
 #include "core/loader/DocumentLoader.h"
 #include "modules/webmidi/MIDIAccessPromise.h"
 #include "modules/webmidi/MIDIConnectionEvent.h"
+#include "modules/webmidi/MIDIController.h"
 #include "modules/webmidi/MIDIInput.h"
 #include "modules/webmidi/MIDIOutput.h"
 #include "modules/webmidi/MIDIPort.h"
 
 namespace WebCore {
 
 PassRefPtr<MIDIAccess> MIDIAccess::create(ScriptExecutionContext* context, MIDIAccessPromise* promise)
 {
     RefPtr<MIDIAccess> midiAccess(adoptRef(new MIDIAccess(context, promise)));
     midiAccess->suspendIfNeeded();
+    midiAccess->startRequest();
     return midiAccess.release();
 }
 
 MIDIAccess::~MIDIAccess()
 {
     stop();
 }
 
 MIDIAccess::MIDIAccess(ScriptExecutionContext* context, MIDIAccessPromise* promise)
     : ActiveDOMObject(context)
     , m_promise(promise)
     , m_hasAccess(false)
+    , m_enableSysEx(false)
+    , m_requesting(false)
 {
     ScriptWrappable::init(this);
     m_accessor = MIDIAccessor::create(this);
-    m_accessor->requestAccess(promise->options()->sysex);
+}
+
+void MIDIAccess::enableSysEx(bool enable)
+{
+    m_requesting = false;
+    m_enableSysEx = enable;
+    if (enable)
+        m_accessor->requestAccess();
+    else
+        didBlockAccess();
 }
 
 void MIDIAccess::didAddInputPort(const String& id, const String& manufacturer, const String& name, const String& version)
 {
     ASSERT(isMainThread());
 
+    // FIXME: Pass m_enableSysEx flag to filter system exclusive messages correctly.
     m_inputs.append(MIDIInput::create(scriptExecutionContext(), id, manufacturer, name, version));
 }
 
 void MIDIAccess::didAddOutputPort(const String& id, const String& manufacturer, const String& name, const String& version)
 {
     ASSERT(isMainThread());
 
+    // FIXME: Pass m_enableSysEx flag to filter system exclusive messages correctly.
     m_outputs.append(MIDIOutput::create(scriptExecutionContext(), id, manufacturer, name, version));
 }
 
 void MIDIAccess::didAllowAccess()
 {
     ASSERT(isMainThread());
 
     m_hasAccess = true;
     m_promise->fulfill();
 }
@@ skipping 20 matching lines @@
 
         double timeStampInMilliseconds = 1000 * document->loader()->timing()->monotonicTimeToZeroBasedDocumentTime(timeStamp);
 
         m_inputs[portIndex]->didReceiveMIDIData(portIndex, data, length, timeStampInMilliseconds);
     }
 }
 
 void MIDIAccess::stop()
 {
     m_hasAccess = false;
+    if (!m_requesting)
+        return;
+    m_requesting = false;
+    Document* document = toDocument(scriptExecutionContext());
+    ASSERT(document);
+    MIDIController* controller = MIDIController::from(document->page());
+    ASSERT(controller);
+    controller->cancelSysExPermissionRequest(this);
+}
+
+void MIDIAccess::startRequest()
+{
+    if (!m_promise->options()->sysex) {
+        m_accessor->requestAccess();
+        return;
+    }
+    Document* document = toDocument(scriptExecutionContext());
+    ASSERT(document);
+    MIDIController* controller = MIDIController::from(document->page());
+    if (controller) {
+        m_requesting = true;
+        controller->requestSysExPermission(this);
+    } else {
+        didBlockAccess();
+    }
 }
 
 } // namespace WebCore