1 /* 2 * Copyright (c) 2015 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #include "modules/rtp_rtcp/source/rtcp_packet/rrtr.h" 12 13 #include "modules/rtp_rtcp/source/byte_io.h" 14 #include "rtc_base/checks.h" 15 16 namespace webrtc { 17 namespace rtcp { 18 // Receiver Reference Time Report Block (RFC 3611). 19 // 20 // 0 1 2 3 21 // 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 22 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 23 // | BT=4 | reserved | block length = 2 | 24 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 25 // | NTP timestamp, most significant word | 26 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 27 // | NTP timestamp, least significant word | 28 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 29 Parse(const uint8_t * buffer)30void Rrtr::Parse(const uint8_t* buffer) { 31 RTC_DCHECK(buffer[0] == kBlockType); 32 // reserved = buffer[1]; 33 RTC_DCHECK(ByteReader<uint16_t>::ReadBigEndian(&buffer[2]) == kBlockLength); 34 uint32_t seconds = ByteReader<uint32_t>::ReadBigEndian(&buffer[4]); 35 uint32_t fraction = ByteReader<uint32_t>::ReadBigEndian(&buffer[8]); 36 ntp_.Set(seconds, fraction); 37 } 38 Create(uint8_t * buffer) const39void Rrtr::Create(uint8_t* buffer) const { 40 const uint8_t kReserved = 0; 41 buffer[0] = kBlockType; 42 buffer[1] = kReserved; 43 ByteWriter<uint16_t>::WriteBigEndian(&buffer[2], kBlockLength); 44 ByteWriter<uint32_t>::WriteBigEndian(&buffer[4], ntp_.seconds()); 45 ByteWriter<uint32_t>::WriteBigEndian(&buffer[8], ntp_.fractions()); 46 } 47 48 } // namespace rtcp 49 } // namespace webrtc 50