1/*
2 *  Copyright (c) 2014 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 "webrtc/modules/audio_coding/neteq/tools/packet.h"
12
13#include <string.h>
14
15#include "webrtc/modules/interface/module_common_types.h"
16#include "webrtc/modules/rtp_rtcp/interface/rtp_header_parser.h"
17
18namespace webrtc {
19namespace test {
20
21Packet::Packet(uint8_t* packet_memory,
22               size_t allocated_bytes,
23               double time_ms,
24               const RtpHeaderParser& parser)
25    : payload_memory_(packet_memory),
26      payload_(NULL),
27      packet_length_bytes_(allocated_bytes),
28      payload_length_bytes_(0),
29      virtual_packet_length_bytes_(allocated_bytes),
30      virtual_payload_length_bytes_(0),
31      time_ms_(time_ms) {
32  valid_header_ = ParseHeader(parser);
33}
34
35Packet::Packet(uint8_t* packet_memory,
36               size_t allocated_bytes,
37               size_t virtual_packet_length_bytes,
38               double time_ms,
39               const RtpHeaderParser& parser)
40    : payload_memory_(packet_memory),
41      payload_(NULL),
42      packet_length_bytes_(allocated_bytes),
43      payload_length_bytes_(0),
44      virtual_packet_length_bytes_(virtual_packet_length_bytes),
45      virtual_payload_length_bytes_(0),
46      time_ms_(time_ms) {
47  valid_header_ = ParseHeader(parser);
48}
49
50Packet::Packet(uint8_t* packet_memory, size_t allocated_bytes, double time_ms)
51    : payload_memory_(packet_memory),
52      payload_(NULL),
53      packet_length_bytes_(allocated_bytes),
54      payload_length_bytes_(0),
55      virtual_packet_length_bytes_(allocated_bytes),
56      virtual_payload_length_bytes_(0),
57      time_ms_(time_ms) {
58  scoped_ptr<RtpHeaderParser> parser(RtpHeaderParser::Create());
59  valid_header_ = ParseHeader(*parser);
60}
61
62Packet::Packet(uint8_t* packet_memory,
63               size_t allocated_bytes,
64               size_t virtual_packet_length_bytes,
65               double time_ms)
66    : payload_memory_(packet_memory),
67      payload_(NULL),
68      packet_length_bytes_(allocated_bytes),
69      payload_length_bytes_(0),
70      virtual_packet_length_bytes_(virtual_packet_length_bytes),
71      virtual_payload_length_bytes_(0),
72      time_ms_(time_ms) {
73  scoped_ptr<RtpHeaderParser> parser(RtpHeaderParser::Create());
74  valid_header_ = ParseHeader(*parser);
75}
76
77bool Packet::ExtractRedHeaders(std::list<RTPHeader*>* headers) const {
78  //
79  //  0                   1                    2                   3
80  //  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
81  // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
82  // |1|   block PT  |  timestamp offset         |   block length    |
83  // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
84  // |1|    ...                                                      |
85  // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
86  // |0|   block PT  |
87  // +-+-+-+-+-+-+-+-+
88  //
89
90  assert(payload_);
91  const uint8_t* payload_ptr = payload_;
92  const uint8_t* payload_end_ptr = payload_ptr + payload_length_bytes_;
93
94  // Find all RED headers with the extension bit set to 1. That is, all headers
95  // but the last one.
96  while ((payload_ptr < payload_end_ptr) && (*payload_ptr & 0x80)) {
97    RTPHeader* header = new RTPHeader;
98    CopyToHeader(header);
99    header->payloadType = payload_ptr[0] & 0x7F;
100    uint32_t offset = (payload_ptr[1] << 6) + ((payload_ptr[2] & 0xFC) >> 2);
101    header->timestamp -= offset;
102    headers->push_front(header);
103    payload_ptr += 4;
104  }
105  // Last header.
106  assert(payload_ptr < payload_end_ptr);
107  if (payload_ptr >= payload_end_ptr) {
108    return false;  // Payload too short.
109  }
110  RTPHeader* header = new RTPHeader;
111  CopyToHeader(header);
112  header->payloadType = payload_ptr[0] & 0x7F;
113  headers->push_front(header);
114  return true;
115}
116
117void Packet::DeleteRedHeaders(std::list<RTPHeader*>* headers) {
118  while (!headers->empty()) {
119    delete headers->front();
120    headers->pop_front();
121  }
122}
123
124void Packet::ConvertHeader(WebRtcRTPHeader* copy_to) const {
125  memcpy(&copy_to->header, &header_, sizeof(header_));
126  copy_to->frameType = kAudioFrameSpeech;
127  copy_to->type.Audio.numEnergy = 0;
128  copy_to->type.Audio.channel = 1;
129  copy_to->type.Audio.isCNG = false;
130}
131
132bool Packet::ParseHeader(const RtpHeaderParser& parser) {
133  bool valid_header = parser.Parse(
134      payload_memory_.get(), static_cast<int>(packet_length_bytes_), &header_);
135  assert(valid_header);
136  if (!valid_header) {
137    return false;
138  }
139  assert(header_.headerLength <= packet_length_bytes_);
140  payload_ = &payload_memory_[header_.headerLength];
141  assert(packet_length_bytes_ >= header_.headerLength);
142  payload_length_bytes_ = packet_length_bytes_ - header_.headerLength;
143  assert(virtual_packet_length_bytes_ >= header_.headerLength);
144  virtual_payload_length_bytes_ =
145      virtual_packet_length_bytes_ - header_.headerLength;
146  return true;
147}
148
149void Packet::CopyToHeader(RTPHeader* destination) const {
150  destination->markerBit = header_.markerBit;
151  destination->payloadType = header_.payloadType;
152  destination->sequenceNumber = header_.sequenceNumber;
153  destination->timestamp = header_.timestamp;
154  destination->ssrc = header_.ssrc;
155  destination->numCSRCs = header_.numCSRCs;
156  destination->paddingLength = header_.paddingLength;
157  destination->headerLength = header_.headerLength;
158  destination->payload_type_frequency = header_.payload_type_frequency;
159  memcpy(&destination->arrOfCSRCs,
160         &header_.arrOfCSRCs,
161         sizeof(header_.arrOfCSRCs));
162  memcpy(
163      &destination->extension, &header_.extension, sizeof(header_.extension));
164}
165
166}  // namespace test
167}  // namespace webrtc
168