meta-info.cpp
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2013-2022 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.
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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/>.
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19  * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
20  */
21 
22 #include "ndn-cxx/meta-info.hpp"
24 
25 #include <boost/range/adaptor/reversed.hpp>
26 
27 namespace ndn {
28 
29 BOOST_CONCEPT_ASSERT((WireEncodable<MetaInfo>));
30 BOOST_CONCEPT_ASSERT((WireEncodableWithEncodingBuffer<MetaInfo>));
31 BOOST_CONCEPT_ASSERT((WireDecodable<MetaInfo>));
32 static_assert(std::is_base_of<tlv::Error, MetaInfo::Error>::value,
33  "MetaInfo::Error must inherit from tlv::Error");
34 
36  : m_type(tlv::ContentType_Blob)
37  , m_freshnessPeriod(DEFAULT_FRESHNESS_PERIOD)
38 {
39 }
40 
42 {
43  wireDecode(block);
44 }
45 
46 MetaInfo&
47 MetaInfo::setType(uint32_t type)
48 {
49  m_wire.reset();
50  m_type = type;
51  return *this;
52 }
53 
54 MetaInfo&
56 {
57  if (freshnessPeriod < time::milliseconds::zero()) {
58  NDN_THROW(std::invalid_argument("FreshnessPeriod must be >= 0"));
59  }
60  m_wire.reset();
61  m_freshnessPeriod = freshnessPeriod;
62  return *this;
63 }
64 
65 MetaInfo&
66 MetaInfo::setFinalBlock(optional<name::Component> finalBlockId)
67 {
68  m_wire.reset();
69  m_finalBlockId = std::move(finalBlockId);
70  return *this;
71 }
72 
73 const std::list<Block>&
75 {
76  return m_appMetaInfo;
77 }
78 
79 MetaInfo&
80 MetaInfo::setAppMetaInfo(const std::list<Block>& info)
81 {
82  for (const auto& block : info) {
83  if (block.type() < 128 || block.type() > 252)
84  NDN_THROW(Error("AppMetaInfo block has type outside the application range [128, 252]"));
85  }
86 
87  m_wire.reset();
88  m_appMetaInfo = info;
89  return *this;
90 }
91 
92 MetaInfo&
94 {
95  if (!(128 <= block.type() && block.type() <= 252))
96  NDN_THROW(Error("AppMetaInfo block has type outside the application range [128, 252]"));
97 
98  m_wire.reset();
99  m_appMetaInfo.push_back(block);
100  return *this;
101 }
102 
103 bool
105 {
106  for (auto it = m_appMetaInfo.begin(); it != m_appMetaInfo.end(); ++it) {
107  if (it->type() == tlvType) {
108  m_wire.reset();
109  m_appMetaInfo.erase(it);
110  return true;
111  }
112  }
113  return false;
114 }
115 
116 const Block*
118 {
119  auto it = std::find_if(m_appMetaInfo.begin(), m_appMetaInfo.end(),
120  [=] (const Block& b) { return b.type() == tlvType; });
121  return it != m_appMetaInfo.end() ? &*it : nullptr;
122 }
123 
124 template<encoding::Tag TAG>
125 size_t
127 {
128  // MetaInfo ::= META-INFO-TYPE TLV-LENGTH
129  // ContentType?
130  // FreshnessPeriod?
131  // FinalBlockId?
132  // AppMetaInfo*
133 
134  size_t totalLength = 0;
135 
136  // AppMetaInfo (in reverse order)
137  for (const auto& block : m_appMetaInfo | boost::adaptors::reversed) {
138  totalLength += prependBlock(encoder, block);
139  }
140 
141  // FinalBlockId
142  if (m_finalBlockId) {
143  totalLength += prependNestedBlock(encoder, tlv::FinalBlockId, *m_finalBlockId);
144  }
145 
146  // FreshnessPeriod
147  if (m_freshnessPeriod != DEFAULT_FRESHNESS_PERIOD) {
149  static_cast<uint64_t>(m_freshnessPeriod.count()));
150  }
151 
152  // ContentType
153  if (m_type != tlv::ContentType_Blob) {
154  totalLength += prependNonNegativeIntegerBlock(encoder, tlv::ContentType, m_type);
155  }
156 
157  totalLength += encoder.prependVarNumber(totalLength);
158  totalLength += encoder.prependVarNumber(tlv::MetaInfo);
159  return totalLength;
160 }
161 
163 
164 const Block&
166 {
167  if (m_wire.hasWire())
168  return m_wire;
169 
170  EncodingEstimator estimator;
171  size_t estimatedSize = wireEncode(estimator);
172 
173  EncodingBuffer buffer(estimatedSize, 0);
174  wireEncode(buffer);
175 
176  m_wire = buffer.block();
177  return m_wire;
178 }
179 
180 void
182 {
183  m_wire = wire;
184  m_wire.parse();
185 
186  // MetaInfo = META-INFO-TYPE TLV-LENGTH
187  // [ContentType]
188  // [FreshnessPeriod]
189  // [FinalBlockId]
190  // *AppMetaInfo
191 
192  auto val = m_wire.elements_begin();
193 
194  // ContentType
195  if (val != m_wire.elements_end() && val->type() == tlv::ContentType) {
196  m_type = readNonNegativeIntegerAs<uint32_t>(*val);
197  ++val;
198  }
199  else {
200  m_type = tlv::ContentType_Blob;
201  }
202 
203  // FreshnessPeriod
204  if (val != m_wire.elements_end() && val->type() == tlv::FreshnessPeriod) {
205  m_freshnessPeriod = time::milliseconds(readNonNegativeInteger(*val));
206  ++val;
207  }
208  else {
209  m_freshnessPeriod = DEFAULT_FRESHNESS_PERIOD;
210  }
211 
212  // FinalBlockId
213  if (val != m_wire.elements_end() && val->type() == tlv::FinalBlockId) {
214  m_finalBlockId.emplace(val->blockFromValue());
215  ++val;
216  }
217  else {
218  m_finalBlockId = nullopt;
219  }
220 
221  // AppMetaInfo (if any)
222  for (; val != m_wire.elements().end(); ++val) {
223  m_appMetaInfo.push_back(*val);
224  }
225 }
226 
227 std::ostream&
228 operator<<(std::ostream& os, const MetaInfo& info)
229 {
230  // ContentType
231  os << "ContentType: " << info.getType();
232 
233  // FreshnessPeriod
234  if (info.getFreshnessPeriod() > 0_ms) {
235  os << ", FreshnessPeriod: " << info.getFreshnessPeriod();
236  }
237 
238  // FinalBlockId
239  if (info.getFinalBlock()) {
240  os << ", FinalBlockId: ";
241  info.getFinalBlock()->toUri(os);
242  }
243 
244  // App-defined MetaInfo items
245  for (const auto& block : info.getAppMetaInfo()) {
246  os << ", AppMetaInfoTlvType: " << block.type();
247  }
248 
249  return os;
250 }
251 
252 } // namespace ndn
Represents a TLV element of the NDN packet format.
Definition: block.hpp:45
element_const_iterator elements_begin() const noexcept
Equivalent to elements().begin().
Definition: block.hpp:435
const element_container & elements() const noexcept
Get container of sub-elements.
Definition: block.hpp:426
element_const_iterator elements_end() const noexcept
Equivalent to elements().end().
Definition: block.hpp:444
bool hasWire() const noexcept
Check if the Block contains a fully encoded wire representation.
Definition: block.hpp:221
uint32_t type() const noexcept
Return the TLV-TYPE of the Block.
Definition: block.hpp:277
void reset() noexcept
Reset the Block to a default-constructed state.
Definition: block.cpp:254
void parse() const
Parse TLV-VALUE into sub-elements.
Definition: block.cpp:324
A MetaInfo holds the meta info which is signed inside the Data packet.
Definition: meta-info.hpp:62
void wireDecode(const Block &wire)
Definition: meta-info.cpp:181
MetaInfo & addAppMetaInfo(const Block &block)
Add an app-defined MetaInfo item.
Definition: meta-info.cpp:93
MetaInfo & setAppMetaInfo(const std::list< Block > &info)
Set app-defined MetaInfo items.
Definition: meta-info.cpp:80
MetaInfo & setType(uint32_t type)
Set ContentType.
Definition: meta-info.cpp:47
MetaInfo & setFinalBlock(optional< name::Component > finalBlockId)
Set FinalBlockId.
Definition: meta-info.cpp:66
const Block & wireEncode() const
Definition: meta-info.cpp:165
const Block * findAppMetaInfo(uint32_t tlvType) const
Find a first app-defined MetaInfo item of type tlvType.
Definition: meta-info.cpp:117
MetaInfo & setFreshnessPeriod(time::milliseconds freshnessPeriod)
Set FreshnessPeriod.
Definition: meta-info.cpp:55
const std::list< Block > & getAppMetaInfo() const
Get all app-defined MetaInfo items.
Definition: meta-info.cpp:74
bool removeAppMetaInfo(uint32_t tlvType)
Remove a first app-defined MetaInfo item with type tlvType.
Definition: meta-info.cpp:104
#define NDN_CXX_DEFINE_WIRE_ENCODE_INSTANTIATIONS(ClassName)
#define NDN_THROW(e)
Definition: exception.hpp:61
EncodingImpl< EstimatorTag > EncodingEstimator
size_t prependNestedBlock(EncodingImpl< TAG > &encoder, uint32_t type, const U &value)
Prepend a TLV element containing a nested TLV element.
uint64_t readNonNegativeInteger(const Block &block)
Read a non-negative integer from a TLV element.
size_t prependNonNegativeIntegerBlock(EncodingImpl< TAG > &encoder, uint32_t type, uint64_t value)
Prepend a TLV element containing a non-negative integer.
EncodingImpl< EncoderTag > EncodingBuffer
size_t prependBlock(EncodingImpl< TAG > &encoder, const Block &block)
Prepend a TLV element.
boost::chrono::milliseconds milliseconds
Definition: time.hpp:48
@ FinalBlockId
Definition: tlv.hpp:98
@ ContentType
Definition: tlv.hpp:96
@ MetaInfo
Definition: tlv.hpp:92
@ FreshnessPeriod
Definition: tlv.hpp:97
@ ContentType_Blob
payload
Definition: tlv.hpp:145
Definition: data.cpp:25
std::ostream & operator<<(std::ostream &os, const Data &data)
Definition: data.cpp:374
const time::milliseconds DEFAULT_FRESHNESS_PERIOD
Default value of FreshnessPeriod.
Definition: meta-info.hpp:38
uint64_t tlvType
TLV-TYPE of the field; 0 if field does not exist.
Definition: packet.cpp:62
SignatureInfo info