Index: media/midi/usb_midi_output_stream.cc |
diff --git a/media/midi/usb_midi_output_stream.cc b/media/midi/usb_midi_output_stream.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..1aef2824676faafcc67d15e1a8f5e1f2aa59df02 |
--- /dev/null |
+++ b/media/midi/usb_midi_output_stream.cc |
@@ -0,0 +1,187 @@ |
+// 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_output_stream.h" |
+ |
+#include "base/logging.h" |
+#include "media/midi/midi_message_util.h" |
+#include "media/midi/usb_midi_device.h" |
+ |
+namespace media { |
+ |
+UsbMidiOutputStream::UsbMidiOutputStream(const UsbMidiJack& jack) |
+ : jack_(jack), pending_size_(0), is_sending_sysex_(false) {} |
+ |
+void UsbMidiOutputStream::Send(const std::vector<uint8>& data) { |
+ // To prevent link errors caused by DCHECK_*. |
+ const size_t kPacketContentSize = UsbMidiOutputStream::kPacketContentSize; |
+ DCHECK_LT(jack_.cable_number, 16u); |
+ |
+ std::vector<uint8> data_to_send; |
+ size_t current = 0; |
+ size_t size = GetSize(data); |
+ while (current < size) { |
+ uint8 first_byte = Get(data, current); |
+ if (first_byte == kSysExByte || is_sending_sysex_) { |
+ // System Exclusive messages |
+ if (!PushSysExMessage(data, ¤t, &data_to_send)) |
+ break; |
+ } else if ((first_byte & kSysMessageBitMask) == kSysMessageBitPattern) { |
+ if (first_byte & 0x08) { |
+ // System Real-Time messages |
+ PushSysRTMessage(data, ¤t, &data_to_send); |
+ } else { |
+ // System Common messages |
+ if (!PushSysCommonMessage(data, ¤t, &data_to_send)) |
+ break; |
+ } |
+ } else if (first_byte & 0x80) { |
+ if (!PushChannelMessage(data, ¤t, &data_to_send)) |
+ break; |
+ } else { |
+ // Unknown messages |
+ DVLOG(1) << "Unknown byte: " << static_cast<unsigned int>(first_byte); |
+ ++current; |
+ } |
+ } |
+ |
+ if (data_to_send.size() > 0) |
+ jack_.device->Send(jack_.endpoint_number(), data_to_send); |
+ |
+ DCHECK_LE(current, size); |
+ DCHECK_LE(size - current, kPacketContentSize); |
+ // Note that this can be a self-copying and the iteration order is important. |
+ for (size_t i = current; i < size; ++i) |
+ pending_data_[i - current] = Get(data, i); |
+ pending_size_ = size - current; |
+} |
+ |
+size_t UsbMidiOutputStream::GetSize(const std::vector<uint8>& data) const { |
+ return data.size() + pending_size_; |
+} |
+ |
+uint8_t UsbMidiOutputStream::Get(const std::vector<uint8>& data, |
+ size_t index) const { |
+ DCHECK_LT(index, GetSize(data)); |
+ if (index < pending_size_) |
+ return pending_data_[index]; |
+ return data[index - pending_size_]; |
+} |
+ |
+bool UsbMidiOutputStream::PushSysExMessage(const std::vector<uint8>& data, |
+ size_t* current, |
+ std::vector<uint8>* data_to_send) { |
+ size_t index = *current; |
+ size_t message_size = 0; |
+ const size_t kMessageSizeMax = 3; |
+ uint8 message[kMessageSizeMax] = {}; |
+ |
+ while (index < GetSize(data)) { |
+ if (message_size == kMessageSizeMax) { |
+ // We can't find the end-of-message mark in the three bytes. |
+ *current = index; |
+ data_to_send->push_back((jack_.cable_number << 4) | 0x4); |
+ data_to_send->insert(data_to_send->end(), |
+ message, |
+ message + arraysize(message)); |
+ is_sending_sysex_ = true; |
+ return true; |
+ } |
+ uint8 byte = Get(data, index); |
+ if ((byte & kSysRTMessageBitMask) == kSysRTMessageBitPattern) { |
+ // System Real-Time messages interleaved in a SysEx message |
+ PushSysRTMessage(data, &index, data_to_send); |
+ continue; |
+ } |
+ |
+ message[message_size] = byte; |
+ ++message_size; |
+ if (byte == kEndOfSysExByte) { |
+ uint8 code_index = message_size + 0x4; |
+ DCHECK(code_index == 0x5 || code_index == 0x6 || code_index == 0x7); |
+ data_to_send->push_back((jack_.cable_number << 4) | code_index); |
+ data_to_send->insert(data_to_send->end(), |
+ message, |
+ message + arraysize(message)); |
+ *current = index + 1; |
+ is_sending_sysex_ = false; |
+ return true; |
+ } |
+ ++index; |
+ } |
+ return false; |
+} |
+ |
+bool UsbMidiOutputStream::PushSysCommonMessage( |
+ const std::vector<uint8>& data, |
+ size_t* current, |
+ std::vector<uint8>* data_to_send) { |
+ size_t index = *current; |
+ uint8 first_byte = Get(data, index); |
+ DCHECK_LE(0xf1, first_byte); |
+ DCHECK_LE(first_byte, 0xf7); |
+ const size_t message_size_table[8] = { |
+ 0, 2, 3, 2, 1, 1, 1, 0, |
+ }; |
+ size_t message_size = message_size_table[first_byte & 0x0f]; |
+ DCHECK_NE(0u, message_size); |
+ DCHECK_LE(message_size, 3u); |
+ |
+ if (GetSize(data) < index + message_size) { |
+ // The message is incomplete. |
+ return false; |
+ } |
+ |
+ uint8 code_index = message_size == 1 ? 0x5 : static_cast<uint8>(message_size); |
+ data_to_send->push_back((jack_.cable_number << 4) | code_index); |
+ for (size_t i = index; i < index + 3; ++i) |
+ data_to_send->push_back(i < index + message_size ? Get(data, i) : 0); |
+ *current += message_size; |
+ return true; |
+} |
+ |
+void UsbMidiOutputStream::PushSysRTMessage(const std::vector<uint8>& data, |
+ size_t* current, |
+ std::vector<uint8>* data_to_send) { |
+ size_t index = *current; |
+ uint8 first_byte = Get(data, index); |
+ DCHECK_LE(0xf8, first_byte); |
+ DCHECK_LE(first_byte, 0xff); |
+ |
+ data_to_send->push_back((jack_.cable_number << 4) | 0x5); |
+ data_to_send->push_back(first_byte); |
+ data_to_send->push_back(0); |
+ data_to_send->push_back(0); |
+ *current += 1; |
+} |
+ |
+bool UsbMidiOutputStream::PushChannelMessage(const std::vector<uint8>& data, |
+ size_t* current, |
+ std::vector<uint8>* data_to_send) { |
+ size_t index = *current; |
+ uint8 first_byte = Get(data, index); |
+ DCHECK_LE(0x80, (first_byte & 0xf0)); |
+ DCHECK_LE((first_byte & 0xf0), 0xe0); |
+ |
+ const size_t message_size_table[8] = { |
+ 3, 3, 3, 3, 2, 3, 3, 0, |
+ }; |
+ uint8 code_index = first_byte >> 4; |
+ size_t message_size = message_size_table[code_index & 0x7]; |
+ DCHECK_NE(0u, message_size); |
+ DCHECK_LE(message_size, 3u); |
+ |
+ if (GetSize(data) < index + message_size) { |
+ // The message is incomplete. |
+ return false; |
+ } |
+ |
+ data_to_send->push_back((jack_.cable_number << 4) | code_index); |
+ for (size_t i = index; i < index + 3; ++i) |
+ data_to_send->push_back(i < index + message_size ? Get(data, i) : 0); |
+ *current += message_size; |
+ return true; |
+} |
+ |
+} // namespace media |