A Discrete-Event Network Simulator
API
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lte-rlc-header.cc
Go to the documentation of this file.
1/*
2 * Copyright (c) 2011 Centre Tecnologic de Telecomunicacions de Catalunya (CTTC)
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation;
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 *
17 * Author: Manuel Requena <manuel.requena@cttc.es>
18 */
19
20#include "lte-rlc-header.h"
21
22#include "ns3/log.h"
23
24namespace ns3
25{
26
27NS_LOG_COMPONENT_DEFINE("LteRlcHeader");
28
29NS_OBJECT_ENSURE_REGISTERED(LteRlcHeader);
30
32 : m_headerLength(0),
33 m_framingInfo(0xff),
34 m_sequenceNumber(0xfffa)
35{
36}
37
39{
41 m_framingInfo = 0xff;
42 m_sequenceNumber = 0xfffb;
43}
44
45void
46LteRlcHeader::SetFramingInfo(uint8_t framingInfo)
47{
48 m_framingInfo = framingInfo & 0x03;
49}
50
51void
53{
54 m_sequenceNumber = sequenceNumber;
55}
56
57uint8_t
59{
60 return m_framingInfo;
61}
62
65{
66 return m_sequenceNumber;
67}
68
69void
70LteRlcHeader::PushExtensionBit(uint8_t extensionBit)
71{
72 m_extensionBits.push_back(extensionBit);
73 if (m_extensionBits.size() == 1)
74 {
75 m_headerLength = 2; // Only fixed part
76 }
77 else if (m_extensionBits.size() % 2)
78 {
79 m_headerLength += 1;
80 }
81 else
82 {
83 m_headerLength += 2;
84 }
85}
86
87void
88LteRlcHeader::PushLengthIndicator(uint16_t lengthIndicator)
89{
90 m_lengthIndicators.push_back(lengthIndicator);
91}
92
93uint8_t
95{
96 uint8_t extensionBit = m_extensionBits.front();
97 m_extensionBits.pop_front();
98
99 return extensionBit;
100}
101
102uint16_t
104{
105 uint16_t lengthIndicator = m_lengthIndicators.front();
106 m_lengthIndicators.pop_front();
107
108 return lengthIndicator;
109}
110
111TypeId
113{
114 static TypeId tid = TypeId("ns3::LteRlcHeader")
115 .SetParent<Header>()
116 .SetGroupName("Lte")
117 .AddConstructor<LteRlcHeader>();
118 return tid;
119}
120
121TypeId
123{
124 return GetTypeId();
125}
126
127void
128LteRlcHeader::Print(std::ostream& os) const
129{
130 auto it1 = m_extensionBits.begin();
131 auto it2 = m_lengthIndicators.begin();
132
133 os << "Len=" << m_headerLength;
134 os << " FI=" << (uint16_t)m_framingInfo;
135 os << " E=" << (uint16_t)(*it1);
136 os << " SN=" << m_sequenceNumber;
137
138 it1++;
139 if (it1 != m_extensionBits.end())
140 {
141 os << " E=";
142 }
143 while (it1 != m_extensionBits.end())
144 {
145 os << (uint16_t)(*it1);
146 it1++;
147 }
148
149 if (it2 != m_lengthIndicators.end())
150 {
151 os << " LI=";
152 }
153 while (it2 != m_lengthIndicators.end())
154 {
155 os << (uint16_t)(*it2) << " ";
156 it2++;
157 }
158}
159
162{
163 return m_headerLength;
164}
165
166void
168{
169 Buffer::Iterator i = start;
170
171 auto it1 = m_extensionBits.begin();
172 auto it2 = m_lengthIndicators.begin();
173
174 i.WriteU8(((m_framingInfo << 3) & 0x18) | (((*it1) << 2) & 0x04) |
175 ((m_sequenceNumber.GetValue() >> 8) & 0x0003));
176 i.WriteU8(m_sequenceNumber.GetValue() & 0x00FF);
177 it1++;
178
179 while (it1 != m_extensionBits.end() && it2 != m_lengthIndicators.end())
180 {
181 uint16_t oddLi;
182 uint16_t evenLi;
183 uint8_t oddE;
184 uint8_t evenE;
185
186 oddE = *it1;
187 oddLi = *it2;
188
189 it1++;
190 it2++;
191
192 if (it1 != m_extensionBits.end() && it2 != m_lengthIndicators.end())
193 {
194 evenE = *it1;
195 evenLi = *it2;
196
197 i.WriteU8(((oddE << 7) & 0x80) | ((oddLi >> 4) & 0x007F));
198 i.WriteU8(((oddLi << 4) & 0x00F0) | ((evenE << 3) & 0x08) | ((evenLi >> 8) & 0x0007));
199 i.WriteU8(evenLi & 0x00FF);
200
201 it1++;
202 it2++;
203 }
204 else
205 {
206 i.WriteU8(((oddE << 7) & 0x80) | ((oddLi >> 4) & 0x007F));
207 i.WriteU8((oddLi << 4) & 0x00F0); // Padding is implicit
208 }
209 }
210}
211
214{
215 Buffer::Iterator i = start;
216 uint8_t byte_1;
217 uint8_t byte_2;
218 uint8_t byte_3;
219 uint8_t extensionBit;
220
221 byte_1 = i.ReadU8();
222 byte_2 = i.ReadU8();
223 m_headerLength = 2;
224 m_framingInfo = (byte_1 & 0x18) >> 3;
225 m_sequenceNumber = ((byte_1 & 0x03) << 8) | byte_2;
226
227 extensionBit = (byte_1 & 0x04) >> 2;
228 m_extensionBits.push_back(extensionBit);
229
230 if (extensionBit == DATA_FIELD_FOLLOWS)
231 {
232 return GetSerializedSize();
233 }
234
235 uint16_t oddLi;
236 uint16_t evenLi;
237 uint8_t oddE;
238 uint8_t evenE;
239 bool moreLiFields = (extensionBit == E_LI_FIELDS_FOLLOWS);
240
241 while (moreLiFields)
242 {
243 byte_1 = i.ReadU8();
244 byte_2 = i.ReadU8();
245
246 oddE = (byte_1 & 0x80) >> 7;
247 oddLi = ((byte_1 & 0x7F) << 4) | ((byte_2 & 0xF0) >> 4);
248 moreLiFields = (oddE == E_LI_FIELDS_FOLLOWS);
249
250 m_extensionBits.push_back(oddE);
251 m_lengthIndicators.push_back(oddLi);
252 m_headerLength += 2;
253
254 if (moreLiFields)
255 {
256 byte_3 = i.ReadU8();
257
258 evenE = (byte_2 & 0x08) >> 3;
259 evenLi = ((byte_2 & 0x07) << 8) | (byte_3 & 0xFF);
260 moreLiFields = (evenE == E_LI_FIELDS_FOLLOWS);
261
262 m_extensionBits.push_back(evenE);
263 m_lengthIndicators.push_back(evenLi);
264
265 m_headerLength += 1;
266 }
267 }
268
269 return GetSerializedSize();
270}
271
272}; // namespace ns3
iterator in a Buffer instance
Definition: buffer.h:100
uint8_t ReadU8()
Definition: buffer.h:1027
void WriteU8(uint8_t data)
Definition: buffer.h:881
Protocol header serialization and deserialization.
Definition: header.h:44
The packet header for the Radio Link Control (RLC) protocol packets.
void Serialize(Buffer::Iterator start) const override
uint8_t m_framingInfo
2 bits
std::list< uint8_t > m_extensionBits
Includes extensionBit of the fixed part.
uint32_t GetSerializedSize() const override
void PushExtensionBit(uint8_t extensionBit)
Push extension bit.
SequenceNumber10 m_sequenceNumber
sequence number
void Print(std::ostream &os) const override
SequenceNumber10 GetSequenceNumber() const
Get sequence number.
uint16_t m_headerLength
header length
void SetSequenceNumber(SequenceNumber10 sequenceNumber)
Set sequence number.
TypeId GetInstanceTypeId() const override
Get the most derived TypeId for this Object.
void SetFramingInfo(uint8_t framingInfo)
Set framing info.
std::list< uint16_t > m_lengthIndicators
length indicators
uint32_t Deserialize(Buffer::Iterator start) override
uint8_t PopExtensionBit()
Pop extension bit.
~LteRlcHeader() override
LteRlcHeader()
Constructor.
uint16_t PopLengthIndicator()
Pop length indicator.
static TypeId GetTypeId()
Get the type ID.
uint8_t GetFramingInfo() const
Get framing info.
void PushLengthIndicator(uint16_t lengthIndicator)
Push length indicator.
SequenceNumber10 class.
uint16_t GetValue() const
Extracts the numeric value of the sequence number.
a unique identifier for an interface.
Definition: type-id.h:59
TypeId SetParent(TypeId tid)
Set the parent TypeId.
Definition: type-id.cc:932
#define NS_LOG_COMPONENT_DEFINE(name)
Define a Log component with a specific name.
Definition: log.h:202
#define NS_OBJECT_ENSURE_REGISTERED(type)
Register an Object subclass with the TypeId system.
Definition: object-base.h:46
Every class exported by the ns3 library is enclosed in the ns3 namespace.