blob: 63ca24b9b8d725369ffdbf220ea0c242b671808b [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/midi/usb_midi_input_stream.h"
#include <string.h>
#include <map>
#include <vector>
#include "base/logging.h"
#include "media/midi/usb_midi_device.h"
#include "media/midi/usb_midi_jack.h"
namespace media {
UsbMidiInputStream::JackUniqueKey::JackUniqueKey(UsbMidiDevice* device,
int endpoint_number,
int cable_number)
: device(device),
endpoint_number(endpoint_number),
cable_number(cable_number) {}
bool UsbMidiInputStream::JackUniqueKey::operator==(
const JackUniqueKey& that) const {
return device == that.device &&
endpoint_number == that.endpoint_number &&
cable_number == that.cable_number;
}
bool UsbMidiInputStream::JackUniqueKey::operator<(
const JackUniqueKey& that) const {
if (device != that.device)
return device < that.device;
if (endpoint_number != that.endpoint_number)
return endpoint_number < that.endpoint_number;
return cable_number < that.cable_number;
}
UsbMidiInputStream::UsbMidiInputStream(Delegate* delegate)
: delegate_(delegate) {}
UsbMidiInputStream::~UsbMidiInputStream() {}
void UsbMidiInputStream::Add(const UsbMidiJack& jack) {
JackUniqueKey key(jack.device,
jack.endpoint_number(),
jack.cable_number);
jacks_.push_back(jack);
DCHECK(jack_dictionary_.end() == jack_dictionary_.find(key));
jack_dictionary_.insert(std::make_pair(key, jack_dictionary_.size()));
}
void UsbMidiInputStream::OnReceivedData(UsbMidiDevice* device,
int endpoint_number,
const uint8* data,
size_t size,
base::TimeTicks time) {
DCHECK_EQ(0u, size % kPacketSize);
size_t current = 0;
while (current + kPacketSize <= size) {
ProcessOnePacket(device, endpoint_number, &data[current], time);
current += kPacketSize;
}
}
void UsbMidiInputStream::ProcessOnePacket(UsbMidiDevice* device,
int endpoint_number,
const uint8* packet,
base::TimeTicks time) {
// The first 4 bytes of the packet is accessible here.
uint8 code_index = packet[0] & 0x0f;
uint8 cable_number = packet[0] >> 4;
const size_t packet_size_table[16] = {
0, 0, 2, 3, 3, 1, 2, 3, 3, 3, 3, 3, 2, 2, 3, 1,
};
size_t packet_size = packet_size_table[code_index];
if (packet_size == 0) {
// These CINs are reserved. Ignore them.
DVLOG(1) << "code index number (" << code_index << ") arrives "
<< "but it is reserved.";
return;
}
std::map<JackUniqueKey, size_t>::const_iterator it =
jack_dictionary_.find(JackUniqueKey(device,
endpoint_number,
cable_number));
if (it != jack_dictionary_.end())
delegate_->OnReceivedData(it->second, &packet[1], packet_size, time);
}
} // namespace media