1 // Copyright 2011 Google Inc.
2 // All rights reserved.
3 //
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5 // modification, are permitted provided that the following conditions are
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7 //
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14 // may be used to endorse or promote products derived from this software
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16 //
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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
stream_length(std::istream & is)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
read_stream(std::istream & input)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