base64-encode.cpp
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5  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
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21 
23 #include "ndn-cxx/security/impl/openssl.hpp"
24 
25 namespace ndn {
26 namespace security {
27 namespace transform {
28 
33 class Base64Encode::Impl
34 {
35 public:
36  Impl()
37  : m_base64(BIO_new(BIO_f_base64()))
38  , m_sink(BIO_new(BIO_s_mem()))
39  {
40  // connect base64 transform to the data sink.
41  BIO_push(m_base64, m_sink);
42  }
43 
44  ~Impl()
45  {
46  BIO_free_all(m_base64);
47  }
48 
49 public:
50  BIO* m_base64;
51  BIO* m_sink; // BIO_f_base64 alone does not work without a sink
52 };
53 
55  : m_impl(make_unique<Impl>())
56 {
57  if (!needBreak)
58  BIO_set_flags(m_impl->m_base64, BIO_FLAGS_BASE64_NO_NL);
59 }
60 
61 Base64Encode::~Base64Encode() = default;
62 
63 void
64 Base64Encode::preTransform()
65 {
66  fillOutputBuffer();
67 }
68 
69 size_t
70 Base64Encode::convert(const uint8_t* data, size_t dataLen)
71 {
72  if (dataLen == 0)
73  return 0;
74 
75  int wLen = BIO_write(m_impl->m_base64, data, dataLen);
76 
77  if (wLen <= 0) { // fail to write data
78  if (!BIO_should_retry(m_impl->m_base64)) {
79  // we haven't written everything but some error happens, and we cannot retry
80  NDN_THROW(Error(getIndex(), "Failed to accept more input"));
81  }
82  return 0;
83  }
84  else { // update number of bytes written
85  fillOutputBuffer();
86  return wLen;
87  }
88 }
89 
90 void
91 Base64Encode::finalize()
92 {
93  if (BIO_flush(m_impl->m_base64) != 1)
94  NDN_THROW(Error(getIndex(), "Failed to flush"));
95 
96  while (!isConverterEmpty()) {
97  fillOutputBuffer();
98  while (!isOutputBufferEmpty()) {
100  }
101  }
102 }
103 
104 void
105 Base64Encode::fillOutputBuffer()
106 {
107  int nRead = BIO_pending(m_impl->m_sink);
108  if (nRead <= 0)
109  return;
110 
111  // there is something to read from BIO
112  auto buffer = make_unique<OBuffer>(nRead);
113  int rLen = BIO_read(m_impl->m_sink, buffer->data(), nRead);
114  if (rLen < 0)
115  return;
116 
117  if (rLen < nRead)
118  buffer->erase(buffer->begin() + rLen, buffer->end());
119  setOutputBuffer(std::move(buffer));
120 }
121 
122 bool
123 Base64Encode::isConverterEmpty()
124 {
125  return (BIO_pending(m_impl->m_sink) <= 0);
126 }
127 
128 unique_ptr<Transform>
129 base64Encode(bool needBreak)
130 {
131  return make_unique<Base64Encode>(needBreak);
132 }
133 
134 } // namespace transform
135 } // namespace security
136 } // namespace ndn
Definition: data.cpp:26
size_t getIndex() const
Get the module index.
bool isOutputBufferEmpty() const
Check if output buffer is empty.
#define NDN_THROW(e)
Definition: exception.hpp:61
void setOutputBuffer(unique_ptr< OBuffer > buffer)
Set output buffer to buffer.
Base64Encode(bool needBreak=true)
Create a base64 encoding module.
Base class of transformation error.
void flushOutputBuffer()
Read the content from output buffer and write it into next module.
unique_ptr< Transform > base64Encode(bool needBreak)