stream-source.cpp
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21 
23 
24 #include <istream>
25 #include <vector>
26 
27 namespace ndn {
28 namespace security {
29 namespace transform {
30 
31 const std::size_t StreamSource::DEFAULT_BUFFER_LEN = 1024;
32 
33 StreamSource::StreamSource(std::istream& is, size_t bufferSize)
34  : Source()
35  , m_is(is)
36  , m_bufferSize(bufferSize)
37 {
38  BOOST_ASSERT(bufferSize > 0);
39 }
40 
41 void
42 StreamSource::doPump()
43 {
44  BOOST_ASSERT(m_next != nullptr);
45 
46  std::vector<uint8_t> buffer(m_bufferSize);
47  size_t dataOffset = 0;
48  size_t dataLen = 0;
49 
50  while (dataLen > 0 || !m_is.eof()) {
51  if (dataLen > 0) {
52  // we have some leftover, handle them first
53  size_t nBytesWritten = m_next->write(&buffer[dataOffset], dataLen);
54 
55  dataOffset += nBytesWritten;
56  dataLen -= nBytesWritten;
57  }
58  else if (!m_is) {
59  NDN_THROW(Error(getIndex(), "Input stream in bad state"));
60  }
61  else if (m_is.good()) {
62  m_is.read(reinterpret_cast<char*>(&buffer.front()), buffer.size());
63  dataOffset = 0;
64  dataLen = m_is.gcount();
65  }
66  }
67  m_next->end();
68 }
69 
70 } // namespace transform
71 } // namespace security
72 } // namespace ndn
Definition: data.cpp:26
#define NDN_THROW(e)
Definition: exception.hpp:61
StreamSource(std::istream &is, size_t bufLen=DEFAULT_BUFFER_LEN)
Construst a source using is as input.
unique_ptr< Downstream > m_next
size_t getIndex() const
Get the source module index (should always be 0).
Base class of transformation error.
Abstraction of the transformation source module.
static const std::size_t DEFAULT_BUFFER_LEN