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.
48std::size_t
49utils::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.
69std::string
70utils::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