1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
|
/*
* Copyright (C) 2008-2014 The QXmpp developers
*
* Author:
* Jeremy Lainé
*
* Source:
* https://github.com/qxmpp-project/qxmpp
*
* This file is a part of QXmpp library.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
*/
#include <QDataStream>
#include "QXmppRtpPacket.h"
#define RTP_VERSION 2
QXmppRtpPacket::QXmppRtpPacket()
: marker(false)
, type(0)
, ssrc(0)
, sequence(0)
, stamp(0)
{
}
QXmppRtpPacket::~QXmppRtpPacket()
{
}
/// Parses an RTP packet.
///
/// \param ba
bool QXmppRtpPacket::decode(const QByteArray &ba)
{
if (ba.isEmpty())
return false;
// fixed header
quint8 tmp;
QDataStream stream(ba);
stream >> tmp;
const quint8 cc = (tmp >> 1) & 0xf;
const int hlen = 12 + 4 * cc;
if ((tmp >> 6) != RTP_VERSION || ba.size() < hlen)
return false;
stream >> tmp;
marker = (tmp >> 7);
type = tmp & 0x7f;
stream >> sequence;
stream >> stamp;
stream >> ssrc;
// contributing source IDs
csrc.clear();
quint32 src;
for (int i = 0; i < cc; ++i) {
stream >> src;
csrc << src;
}
// retrieve payload
payload = ba.right(ba.size() - hlen);
return true;
}
/// Encodes an RTP packet.
QByteArray QXmppRtpPacket::encode() const
{
Q_ASSERT(csrc.size() < 16);
// fixed header
QByteArray ba;
ba.resize(payload.size() + 12 + 4 * csrc.size());
QDataStream stream(&ba, QIODevice::WriteOnly);
stream << quint8((RTP_VERSION << 6) |
((csrc.size() & 0xf) << 1));
stream << quint8((type & 0x7f) | (marker << 7));
stream << sequence;
stream << stamp;
stream << ssrc;
// contributing source ids
foreach (const quint32 &src, csrc)
stream << src;
stream.writeRawData(payload.constData(), payload.size());
return ba;
}
/// Returns a string representation of the RTP header.
QString QXmppRtpPacket::toString() const
{
return QString("RTP packet seq %1 stamp %2 marker %3 type %4 size %5").arg(
QString::number(sequence),
QString::number(stamp),
QString::number(marker),
QString::number(type),
QString::number(payload.size()));
}
|
