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      1 /*
      2  * Copyright (C) 2013 Google Inc. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions are
      6  * met:
      7  *
      8  *     * Redistributions of source code must retain the above copyright
      9  * notice, this list of conditions and the following disclaimer.
     10  *     * Redistributions in binary form must reproduce the above
     11  * copyright notice, this list of conditions and the following disclaimer
     12  * in the documentation and/or other materials provided with the
     13  * distribution.
     14  *     * Neither the name of Google Inc. nor the names of its
     15  * contributors may be used to endorse or promote products derived from
     16  * this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #include "config.h"
     32 #include "modules/webmidi/MIDIAccess.h"
     33 
     34 #include "core/dom/Document.h"
     35 #include "core/loader/DocumentLoadTiming.h"
     36 #include "core/loader/DocumentLoader.h"
     37 #include "modules/webmidi/MIDIAccessInitializer.h"
     38 #include "modules/webmidi/MIDIConnectionEvent.h"
     39 #include "modules/webmidi/MIDIController.h"
     40 #include "modules/webmidi/MIDIInput.h"
     41 #include "modules/webmidi/MIDIInputMap.h"
     42 #include "modules/webmidi/MIDIOutput.h"
     43 #include "modules/webmidi/MIDIOutputMap.h"
     44 #include "modules/webmidi/MIDIPort.h"
     45 #include "platform/AsyncMethodRunner.h"
     46 #include <v8.h>
     47 
     48 namespace blink {
     49 
     50 MIDIAccess::MIDIAccess(PassOwnPtr<MIDIAccessor> accessor, bool sysexEnabled, const Vector<MIDIAccessInitializer::PortDescriptor>& ports, ExecutionContext* executionContext)
     51     : ActiveDOMObject(executionContext)
     52     , m_accessor(accessor)
     53     , m_sysexEnabled(sysexEnabled)
     54 {
     55     m_accessor->setClient(this);
     56     for (size_t i = 0; i < ports.size(); ++i) {
     57         const MIDIAccessInitializer::PortDescriptor& port = ports[i];
     58         if (port.type == MIDIPort::MIDIPortTypeInput) {
     59             m_inputs.append(MIDIInput::create(this, port.id, port.manufacturer, port.name, port.version));
     60         } else {
     61             m_outputs.append(MIDIOutput::create(this, m_outputs.size(), port.id, port.manufacturer, port.name, port.version));
     62         }
     63     }
     64 }
     65 
     66 MIDIAccess::~MIDIAccess()
     67 {
     68 }
     69 
     70 MIDIInputMap* MIDIAccess::inputs() const
     71 {
     72     HeapHashMap<String, Member<MIDIInput> > inputs;
     73     for (size_t i = 0; i < m_inputs.size(); ++i) {
     74         MIDIInput* input = m_inputs[i];
     75         inputs.add(input->id(), input);
     76     }
     77     if (inputs.size() != m_inputs.size()) {
     78         // There is id duplication that violates the spec.
     79         inputs.clear();
     80     }
     81     return new MIDIInputMap(inputs);
     82 }
     83 
     84 MIDIOutputMap* MIDIAccess::outputs() const
     85 {
     86     HeapHashMap<String, Member<MIDIOutput> > outputs;
     87     for (size_t i = 0; i < m_outputs.size(); ++i) {
     88         MIDIOutput* output = m_outputs[i];
     89         outputs.add(output->id(), output);
     90     }
     91     if (outputs.size() != m_outputs.size()) {
     92         // There is id duplication that violates the spec.
     93         outputs.clear();
     94     }
     95     return new MIDIOutputMap(outputs);
     96 }
     97 
     98 void MIDIAccess::didAddInputPort(const String& id, const String& manufacturer, const String& name, const String& version)
     99 {
    100     ASSERT(isMainThread());
    101     m_inputs.append(MIDIInput::create(this, id, manufacturer, name, version));
    102 }
    103 
    104 void MIDIAccess::didAddOutputPort(const String& id, const String& manufacturer, const String& name, const String& version)
    105 {
    106     ASSERT(isMainThread());
    107     unsigned portIndex = m_outputs.size();
    108     m_outputs.append(MIDIOutput::create(this, portIndex, id, manufacturer, name, version));
    109 }
    110 
    111 void MIDIAccess::didReceiveMIDIData(unsigned portIndex, const unsigned char* data, size_t length, double timeStamp)
    112 {
    113     ASSERT(isMainThread());
    114     if (portIndex >= m_inputs.size())
    115         return;
    116 
    117     // Convert from time in seconds which is based on the time coordinate system of monotonicallyIncreasingTime()
    118     // into time in milliseconds (a DOMHighResTimeStamp) according to the same time coordinate system as performance.now().
    119     // This is how timestamps are defined in the Web MIDI spec.
    120     Document* document = toDocument(executionContext());
    121     ASSERT(document);
    122 
    123     double timeStampInMilliseconds = 1000 * document->loader()->timing()->monotonicTimeToZeroBasedDocumentTime(timeStamp);
    124 
    125     m_inputs[portIndex]->didReceiveMIDIData(portIndex, data, length, timeStampInMilliseconds);
    126 }
    127 
    128 void MIDIAccess::sendMIDIData(unsigned portIndex, const unsigned char* data, size_t length, double timeStampInMilliseconds)
    129 {
    130     if (!data || !length || portIndex >= m_outputs.size())
    131         return;
    132     // Convert from a time in milliseconds (a DOMHighResTimeStamp) according to the same time coordinate system as performance.now()
    133     // into a time in seconds which is based on the time coordinate system of monotonicallyIncreasingTime().
    134     double timeStamp;
    135 
    136     if (!timeStampInMilliseconds) {
    137         // We treat a value of 0 (which is the default value) as special, meaning "now".
    138         // We need to translate it exactly to 0 seconds.
    139         timeStamp = 0;
    140     } else {
    141         Document* document = toDocument(executionContext());
    142         ASSERT(document);
    143         double documentStartTime = document->loader()->timing()->referenceMonotonicTime();
    144         timeStamp = documentStartTime + 0.001 * timeStampInMilliseconds;
    145     }
    146 
    147     m_accessor->sendMIDIData(portIndex, data, length, timeStamp);
    148 }
    149 
    150 void MIDIAccess::stop()
    151 {
    152     m_accessor.clear();
    153 }
    154 
    155 void MIDIAccess::trace(Visitor* visitor)
    156 {
    157     visitor->trace(m_inputs);
    158     visitor->trace(m_outputs);
    159     EventTargetWithInlineData::trace(visitor);
    160 }
    161 
    162 } // namespace blink
    163