io.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).
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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.
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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 "io.hpp"
23 #include "../encoding/buffer-stream.hpp"
24 #include "../security/transform.hpp"
25 
26 namespace ndn {
27 namespace io {
28 
30 loadBlock(std::istream& is, IoEncoding encoding)
31 {
32  namespace t = ndn::security::transform;
33 
34  OBufferStream os;
35  try {
36  switch (encoding) {
37  case NO_ENCODING:
38  t::streamSource(is) >> t::streamSink(os);
39  break;
40  case BASE64:
41  t::streamSource(is) >> t::stripSpace("\n") >> t::base64Decode(false) >> t::streamSink(os);
42  break;
43  case HEX:
45  break;
46  default:
47  return nullopt;
48  }
49  }
50  catch (const t::Error&) {
51  return nullopt;
52  }
53 
54  try {
55  return make_optional<Block>(os.buf());
56  }
57  catch (const tlv::Error&) {
58  return nullopt;
59  }
60  catch (const std::invalid_argument&) {
61  return nullopt;
62  }
63 }
64 
65 void
66 saveBlock(const Block& block, std::ostream& os, IoEncoding encoding)
67 {
68  namespace t = ndn::security::transform;
69 
70  try {
71  switch (encoding) {
72  case NO_ENCODING:
73  t::bufferSource(block.wire(), block.size()) >> t::streamSink(os);
74  break;
75  case BASE64:
76  t::bufferSource(block.wire(), block.size()) >> t::base64Encode() >> t::streamSink(os);
77  break;
78  case HEX:
79  t::bufferSource(block.wire(), block.size()) >> t::hexEncode(true) >> t::streamSink(os);
80  break;
81  default:
82  BOOST_THROW_EXCEPTION(Error("unrecognized IoEncoding"));
83  }
84  }
85  catch (const t::Error& e) {
86  BOOST_THROW_EXCEPTION(Error(e.what()));
87  }
88 }
89 
90 } // namespace io
91 } // namespace ndn
optional< Block > loadBlock(std::istream &is, IoEncoding encoding)
loads a TLV block from a stream
Definition: io.cpp:30
constexpr nullopt_t nullopt
void saveBlock(const Block &block, std::ostream &os, IoEncoding encoding)
saves a TLV block to a stream
Definition: io.cpp:66
Copyright (c) 2013-2017 Regents of the University of California.
Definition: common.hpp:66
unique_ptr< Transform > base64Decode(bool expectNewlineEvery64Bytes)
unique_ptr< Transform > hexEncode(bool useUpperCase)
Definition: hex-encode.cpp:70
Represents a TLV element of NDN packet format.
Definition: block.hpp:42
unique_ptr< Transform > stripSpace(const char *whitespaces)
constructs a StripSpace transform
Definition: strip-space.cpp:55
size_t size() const
Get size of encoded wire, including Type-Length-Value.
Definition: block.cpp:300
hexadecimal encoding
Definition: io.hpp:61
binary without encoding
Definition: io.hpp:48
unique_ptr< Sink > streamSink(std::ostream &os)
Definition: stream-sink.cpp:53
unique_ptr< Transform > hexDecode()
Definition: hex-decode.cpp:114
shared_ptr< Buffer > buf()
Flush written data to the stream and return shared pointer to the underlying buffer.
const uint8_t * wire() const
Get pointer to encoded wire.
Definition: block.cpp:291
implements an output stream that constructs ndn::Buffer
base64 encoding
Definition: io.hpp:55
represents an error in TLV encoding or decoding
unique_ptr< Transform > base64Encode(bool needBreak)
IoEncoding
indicates how a file or stream is encoded
Definition: io.hpp:45