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/*
* Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/modules/rtp_rtcp/source/rtcp_packet/app.h"
#include "webrtc/base/checks.h"
#include "webrtc/base/logging.h"
#include "webrtc/modules/rtp_rtcp/source/byte_io.h"
using webrtc::RTCPUtility::RtcpCommonHeader;
namespace webrtc {
namespace rtcp {
// Application-Defined packet (APP) (RFC 3550).
//
// 0 1 2 3
// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// |V=2|P| subtype | PT=APP=204 | length |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// 0 | SSRC/CSRC |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// 4 | name (ASCII) |
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// 8 | application-dependent data ...
// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
bool App::Parse(const RtcpCommonHeader& header, const uint8_t* payload) {
RTC_DCHECK(header.packet_type == kPacketType);
sub_type_ = header.count_or_format;
ssrc_ = ByteReader<uint32_t>::ReadBigEndian(&payload[0]);
name_ = ByteReader<uint32_t>::ReadBigEndian(&payload[4]);
data_.SetData(&payload[8], header.payload_size_bytes - 8);
return true;
}
void App::WithSubType(uint8_t subtype) {
RTC_DCHECK_LE(subtype, 0x1f);
sub_type_ = subtype;
}
void App::WithData(const uint8_t* data, size_t data_length) {
RTC_DCHECK(data);
RTC_DCHECK_EQ(0u, data_length % 4) << "Data must be 32 bits aligned.";
RTC_DCHECK(data_length <= kMaxDataSize) << "App data size << " << data_length
<< "exceed maximum of "
<< kMaxDataSize << " bytes.";
data_.SetData(data, data_length);
}
bool App::Create(uint8_t* packet,
size_t* index,
size_t max_length,
RtcpPacket::PacketReadyCallback* callback) const {
while (*index + BlockLength() > max_length) {
if (!OnBufferFull(packet, index, callback))
return false;
}
const size_t index_end = *index + BlockLength();
CreateHeader(sub_type_, kPacketType, HeaderLength(), packet, index);
ByteWriter<uint32_t>::WriteBigEndian(&packet[*index + 0], ssrc_);
ByteWriter<uint32_t>::WriteBigEndian(&packet[*index + 4], name_);
memcpy(&packet[*index + 8], data_.data(), data_.size());
*index += (8 + data_.size());
RTC_DCHECK_EQ(index_end, *index);
return true;
}
} // namespace rtcp
} // namespace webrtc
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