summaryrefslogtreecommitdiffstats
path: root/src/fmtlib/fmt/ostream.h
blob: ce65909b95f09f5b19b8c62f2e266b217d51a624 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
// Formatting library for C++ - std::ostream support
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.

#ifndef FMT_OSTREAM_H_
#define FMT_OSTREAM_H_

#include <fstream>  // std::filebuf

#if defined(_WIN32) && defined(__GLIBCXX__)
#  include <ext/stdio_filebuf.h>
#  include <ext/stdio_sync_filebuf.h>
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
#  include <__std_stream>
#endif

#include "format.h"

FMT_BEGIN_NAMESPACE

namespace detail {

// Generate a unique explicit instantion in every translation unit using a tag
// type in an anonymous namespace.
namespace {
struct file_access_tag {};
}  // namespace
template <typename Tag, typename BufType, FILE* BufType::*FileMemberPtr>
class file_access {
  friend auto get_file(BufType& obj) -> FILE* { return obj.*FileMemberPtr; }
};

#if FMT_MSC_VERSION
template class file_access<file_access_tag, std::filebuf,
                           &std::filebuf::_Myfile>;
auto get_file(std::filebuf&) -> FILE*;
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
template class file_access<file_access_tag, std::__stdoutbuf<char>,
                           &std::__stdoutbuf<char>::__file_>;
auto get_file(std::__stdoutbuf<char>&) -> FILE*;
#endif

inline bool write_ostream_unicode(std::ostream& os, fmt::string_view data) {
#if FMT_MSC_VERSION
  if (auto* buf = dynamic_cast<std::filebuf*>(os.rdbuf()))
    if (FILE* f = get_file(*buf)) return write_console(f, data);
#elif defined(_WIN32) && defined(__GLIBCXX__)
  auto* rdbuf = os.rdbuf();
  FILE* c_file;
  if (auto* sfbuf = dynamic_cast<__gnu_cxx::stdio_sync_filebuf<char>*>(rdbuf))
    c_file = sfbuf->file();
  else if (auto* fbuf = dynamic_cast<__gnu_cxx::stdio_filebuf<char>*>(rdbuf))
    c_file = fbuf->file();
  else
    return false;
  if (c_file) return write_console(c_file, data);
#elif defined(_WIN32) && defined(_LIBCPP_VERSION)
  if (auto* buf = dynamic_cast<std::__stdoutbuf<char>*>(os.rdbuf()))
    if (FILE* f = get_file(*buf)) return write_console(f, data);
#else
  ignore_unused(os, data);
#endif
  return false;
}
inline bool write_ostream_unicode(std::wostream&,
                                  fmt::basic_string_view<wchar_t>) {
  return false;
}

// Write the content of buf to os.
// It is a separate function rather than a part of vprint to simplify testing.
template <typename Char>
void write_buffer(std::basic_ostream<Char>& os, buffer<Char>& buf) {
  const Char* buf_data = buf.data();
  using unsigned_streamsize = std::make_unsigned<std::streamsize>::type;
  unsigned_streamsize size = buf.size();
  unsigned_streamsize max_size = to_unsigned(max_value<std::streamsize>());
  do {
    unsigned_streamsize n = size <= max_size ? size : max_size;
    os.write(buf_data, static_cast<std::streamsize>(n));
    buf_data += n;
    size -= n;
  } while (size != 0);
}

template <typename Char, typename T>
void format_value(buffer<Char>& buf, const T& value,
                  locale_ref loc = locale_ref()) {
  auto&& format_buf = formatbuf<std::basic_streambuf<Char>>(buf);
  auto&& output = std::basic_ostream<Char>(&format_buf);
#if !defined(FMT_STATIC_THOUSANDS_SEPARATOR)
  if (loc) output.imbue(loc.get<std::locale>());
#endif
  output << value;
  output.exceptions(std::ios_base::failbit | std::ios_base::badbit);
}

template <typename T> struct streamed_view { const T& value; };

}  // namespace detail

// Formats an object of type T that has an overloaded ostream operator<<.
template <typename Char>
struct basic_ostream_formatter : formatter<basic_string_view<Char>, Char> {
  void set_debug_format() = delete;

  template <typename T, typename OutputIt>
  auto format(const T& value, basic_format_context<OutputIt, Char>& ctx) const
      -> OutputIt {
    auto buffer = basic_memory_buffer<Char>();
    detail::format_value(buffer, value, ctx.locale());
    return formatter<basic_string_view<Char>, Char>::format(
        {buffer.data(), buffer.size()}, ctx);
  }
};

using ostream_formatter = basic_ostream_formatter<char>;

template <typename T, typename Char>
struct formatter<detail::streamed_view<T>, Char>
    : basic_ostream_formatter<Char> {
  template <typename OutputIt>
  auto format(detail::streamed_view<T> view,
              basic_format_context<OutputIt, Char>& ctx) const -> OutputIt {
    return basic_ostream_formatter<Char>::format(view.value, ctx);
  }
};

/**
  \rst
  Returns a view that formats `value` via an ostream ``operator<<``.

  **Example**::

    fmt::print("Current thread id: {}\n",
               fmt::streamed(std::this_thread::get_id()));
  \endrst
 */
template <typename T>
auto streamed(const T& value) -> detail::streamed_view<T> {
  return {value};
}

namespace detail {

inline void vprint_directly(std::ostream& os, string_view format_str,
                            format_args args) {
  auto buffer = memory_buffer();
  detail::vformat_to(buffer, format_str, args);
  detail::write_buffer(os, buffer);
}

}  // namespace detail

FMT_MODULE_EXPORT template <typename Char>
void vprint(std::basic_ostream<Char>& os,
            basic_string_view<type_identity_t<Char>> format_str,
            basic_format_args<buffer_context<type_identity_t<Char>>> args) {
  auto buffer = basic_memory_buffer<Char>();
  detail::vformat_to(buffer, format_str, args);
  if (detail::write_ostream_unicode(os, {buffer.data(), buffer.size()})) return;
  detail::write_buffer(os, buffer);
}

/**
  \rst
  Prints formatted data to the stream *os*.

  **Example**::

    fmt::print(cerr, "Don't {}!", "panic");
  \endrst
 */
FMT_MODULE_EXPORT template <typename... T>
void print(std::ostream& os, format_string<T...> fmt, T&&... args) {
  const auto& vargs = fmt::make_format_args(args...);
  if (detail::is_utf8())
    vprint(os, fmt, vargs);
  else
    detail::vprint_directly(os, fmt, vargs);
}

FMT_MODULE_EXPORT
template <typename... Args>
void print(std::wostream& os,
           basic_format_string<wchar_t, type_identity_t<Args>...> fmt,
           Args&&... args) {
  vprint(os, fmt, fmt::make_format_args<buffer_context<wchar_t>>(args...));
}

FMT_MODULE_EXPORT template <typename... T>
void println(std::ostream& os, format_string<T...> fmt, T&&... args) {
  fmt::print(os, "{}\n", fmt::format(fmt, std::forward<T>(args)...));
}

FMT_MODULE_EXPORT
template <typename... Args>
void println(std::wostream& os,
             basic_format_string<wchar_t, type_identity_t<Args>...> fmt,
             Args&&... args) {
  print(os, L"{}\n", fmt::format(fmt, std::forward<Args>(args)...));
}

FMT_END_NAMESPACE

#endif  // FMT_OSTREAM_H_