external/bsd/kyua-cli/dist/utils/stream.cpp

   1 // Copyright 2011 Google Inc.
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  28
  29 #include "utils/stream.hpp"
  30
  31 #include <istream>
  32 #include <sstream>
  33
  34 #include "utils/format/macros.hpp"
  35 #include "utils/sanity.hpp"
  36
  37
  38 /// Gets the length of a stream.
  39 ///
  40 /// \param is The input stream for which to calculate its length.
  41 ///
  42 /// \return The length of the stream.  This is of size_t type instead of
  43 /// directly std::streampos to simplify the caller.  Some systems do not
  44 /// support comparing a std::streampos directly to an integer (see
  45 /// NetBSD 1.5.x), which is what we often want to do.
  46 ///
  47 /// \throw std::exception If calculating the length fails due to a stream error.
  48 std::size_t
  49 utils::stream_length(std::istream& is)
  50 {
  51     const std::streampos current_pos = is.tellg();
  52     try {
  53         is.seekg(0, std::ios::end);
  54         const std::streampos length = is.tellg();
  55         is.seekg(current_pos, std::ios::beg);
  56         return static_cast< std::size_t >(length);
  57     } catch (...) {
  58         is.seekg(current_pos, std::ios::beg);
  59         throw;
  60     }
  61 }
  62
  63
  64 /// Reads the whole contents of a stream into memory.
  65 ///
  66 /// \param input The input stream from which to read.
  67 ///
  68 /// \return A plain string containing the raw contents of the file.
  69 std::string
  70 utils::read_stream(std::istream& input)
  71 {
  72     std::ostringstream buffer;
  73
  74     char tmp[1024];
  75     while (input.good()) {
  76         input.read(tmp, sizeof(tmp));
  77         if (input.good() || input.eof()) {
  78             buffer.write(tmp, input.gcount());
  79         }
  80     }
  81
  82     return buffer.str();
  83 }