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