NS-3 based Named Data Networking (NDN) simulator
ndnSIM 2.5: NDN, CCN, CCNx, content centric networks
API Documentation
nack-header.cpp
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2013-2018 Regents of the University of California.
4  *
5  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
6  *
7  * ndn-cxx library is free software: you can redistribute it and/or modify it under the
8  * terms of the GNU Lesser General Public License as published by the Free Software
9  * Foundation, either version 3 of the License, or (at your option) any later version.
10  *
11  * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
12  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
13  * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
14  *
15  * You should have received copies of the GNU General Public License and GNU Lesser
16  * General Public License along with ndn-cxx, e.g., in COPYING.md file. If not, see
17  * <http://www.gnu.org/licenses/>.
18  *
19  * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
20  *
21  * @author Eric Newberry <enewberry@email.arizona.edu>
22  */
23 
25 
26 namespace ndn {
27 namespace lp {
28 
29 std::ostream&
30 operator<<(std::ostream& os, NackReason reason)
31 {
32  switch (reason) {
34  os << "Congestion";
35  break;
37  os << "Duplicate";
38  break;
40  os << "NoRoute";
41  break;
42  default:
43  os << "None";
44  break;
45  }
46  return os;
47 }
48 
49 bool
51 {
52  if (x == lp::NackReason::NONE) {
53  return false;
54  }
55  if (y == lp::NackReason::NONE) {
56  return true;
57  }
58 
59  return static_cast<int>(x) < static_cast<int>(y);
60 }
61 
63  : m_reason(NackReason::NONE)
64 {
65 }
66 
68 {
69  wireDecode(block);
70 }
71 
72 template<encoding::Tag TAG>
73 size_t
75 {
76  size_t length = 0;
77  length += prependNonNegativeIntegerBlock(encoder, tlv::NackReason, static_cast<uint32_t>(m_reason));
78  length += encoder.prependVarNumber(length);
79  length += encoder.prependVarNumber(tlv::Nack);
80  return length;
81 }
82 
84 
85 const Block&
87 {
88  if (m_wire.hasWire()) {
89  return m_wire;
90  }
91 
92  EncodingEstimator estimator;
93  size_t estimatedSize = wireEncode(estimator);
94 
95  EncodingBuffer buffer(estimatedSize, 0);
96  wireEncode(buffer);
97 
98  m_wire = buffer.block();
99 
100  return m_wire;
101 }
102 
103 void
105 {
106  if (wire.type() != tlv::Nack) {
107  BOOST_THROW_EXCEPTION(ndn::tlv::Error("expecting Nack block"));
108  }
109 
110  m_wire = wire;
111  m_wire.parse();
112  m_reason = NackReason::NONE;
113 
114  if (m_wire.elements_size() > 0) {
116 
117  if (it->type() == tlv::NackReason) {
118  m_reason = static_cast<NackReason>(readNonNegativeInteger(*it));
119  }
120  else {
121  BOOST_THROW_EXCEPTION(ndn::tlv::Error("expecting NackReason block"));
122  }
123  }
124 }
125 
128 {
129  switch (m_reason) {
133  return m_reason;
134  default:
135  return NackReason::NONE;
136  }
137 }
138 
139 NackHeader&
141 {
142  m_reason = reason;
143  m_wire.reset();
144  return *this;
145 }
146 
147 } // namespace lp
148 } // namespace ndn
bool hasWire() const
Check if the Block has fully encoded wire.
Definition: block.cpp:249
Copyright (c) 2011-2015 Regents of the University of California.
NDN_CXX_DEFINE_WIRE_ENCODE_INSTANTIATIONS(CachePolicy)
size_t prependNonNegativeIntegerBlock(EncodingImpl< TAG > &encoder, uint32_t type, uint64_t value)
Prepend a TLV element containing a non-negative integer.
NackHeader & setReason(NackReason reason)
set reason code
const Block & wireEncode() const
Definition: nack-header.cpp:86
element_container::const_iterator element_const_iterator
Definition: block.hpp:47
void parse() const
Parse TLV-VALUE into sub elements.
Definition: block.cpp:333
Represents a TLV element of NDN packet format.
Definition: block.hpp:42
void wireDecode(const Block &wire)
NackReason
indicates the reason type of a network NACK
Definition: nack-header.hpp:37
element_const_iterator elements_begin() const
Equivalent to elements().begin()
Definition: block.hpp:369
uint64_t readNonNegativeInteger(const Block &block)
Read a non-negative integer from a TLV element.
NackReason getReason() const
void reset()
Reset wire buffer of the element.
Definition: block.cpp:255
size_t elements_size() const
Equivalent to elements().size()
Definition: block.hpp:385
std::ostream & operator<<(std::ostream &os, CachePolicyType policy)
bool isLessSevere(lp::NackReason x, lp::NackReason y)
compare NackReason for severity
Definition: nack-header.cpp:50
represents a Network NACK header
Definition: nack-header.hpp:57
EncodingImpl< EncoderTag > EncodingBuffer
uint32_t type() const
Get TLV-TYPE.
Definition: block.hpp:249
represents an error in TLV encoding or decoding
Definition: tlv.hpp:52
EncodingImpl< EstimatorTag > EncodingEstimator