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      5 // modification, are permitted provided that the following conditions are
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      9 //   notice, this list of conditions and the following disclaimer.
     10 // * Redistributions in binary form must reproduce the above copyright
     11 //   notice, this list of conditions and the following disclaimer in the
     12 //   documentation and/or other materials provided with the distribution.
     13 // * Neither the name of Google Inc. nor the names of its contributors
     14 //   may be used to endorse or promote products derived from this software
     15 //   without specific prior written permission.
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     17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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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 }
     84