1// <print> Print functions -*- C++ -*-
2
3// Copyright The GNU Toolchain Authors.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file include/print
26 * This is a Standard C++ Library header.
27 */
28
29#ifndef _GLIBCXX_PRINT
30#define _GLIBCXX_PRINT 1
31
32#pragma GCC system_header
33
34#include <bits/requires_hosted.h> // for std::format
35
36#define __glibcxx_want_print
37#include <bits/version.h>
38
39#ifdef __cpp_lib_print // C++ >= 23
40
41#include <format>
42#include <cstdio>
43#include <cerrno>
44#include <bits/functexcept.h>
45
46#ifdef _WIN32
47# include <system_error>
48#endif
49
50namespace std _GLIBCXX_VISIBILITY(default)
51{
52_GLIBCXX_BEGIN_NAMESPACE_VERSION
53
54 inline void
55 vprint_nonunicode(FILE* __stream, string_view __fmt, format_args __args)
56 {
57 __format::_Str_sink<char> __buf;
58 std::vformat_to(out: __buf.out(), __fmt, __args);
59 auto __out = __buf.view();
60 if (std::fwrite(ptr: __out.data(), size: 1, n: __out.size(), s: __stream) != __out.size())
61 __throw_system_error(EIO);
62 }
63
64 inline void
65 vprint_unicode(FILE* __stream, string_view __fmt, format_args __args)
66 {
67#if !defined(_WIN32) || defined(__CYGWIN__)
68 // For most targets we don't need to do anything special to write
69 // Unicode to a terminal.
70 std::vprint_nonunicode(__stream, __fmt, __args);
71#else
72 __format::_Str_sink<char> __buf;
73 std::vformat_to(__buf.out(), __fmt, __args);
74 auto __out = __buf.view();
75
76 void* __open_terminal(FILE*);
77 error_code __write_to_terminal(void*, span<char>);
78 // If stream refers to a terminal, write a native Unicode string to it.
79 if (auto __term = __open_terminal(__stream))
80 {
81 string __out = std::vformat(__fmt, __args);
82 error_code __e;
83 if (!std::fflush(__stream))
84 {
85 __e = __write_to_terminal(__term, __out);
86 if (!__e)
87 return;
88 if (__e == std::make_error_code(errc::illegal_byte_sequence))
89 return;
90 }
91 else
92 __e = error_code(errno, generic_category());
93 _GLIBCXX_THROW_OR_ABORT(system_error(__e, "std::vprint_unicode"));
94 }
95
96 // Otherwise just write the string to the file as vprint_nonunicode does.
97 if (std::fwrite(__out.data(), 1, __out.size(), __stream) != __out.size())
98 __throw_system_error(EIO);
99#endif
100 }
101
102 template<typename... _Args>
103 inline void
104 print(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args)
105 {
106 auto __fmtargs = std::make_format_args(__args...);
107 if constexpr (__unicode::__literal_encoding_is_utf8())
108 std::vprint_unicode(__stream, fmt: __fmt.get(), args: __fmtargs);
109 else
110 std::vprint_nonunicode(__stream, fmt: __fmt.get(), args: __fmtargs);
111 }
112
113 template<typename... _Args>
114 inline void
115 print(format_string<_Args...> __fmt, _Args&&... __args)
116 { std::print(stdout, __fmt, std::forward<_Args>(__args)...); }
117
118 template<typename... _Args>
119 inline void
120 println(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args)
121 {
122 std::print(__stream, "{}\n",
123 std::format(__fmt, std::forward<_Args>(__args)...));
124 }
125
126 template<typename... _Args>
127 inline void
128 println(format_string<_Args...> __fmt, _Args&&... __args)
129 { std::println(stdout, __fmt, std::forward<_Args>(__args)...); }
130
131 inline void
132 vprint_unicode(string_view __fmt, format_args __args)
133 { std::vprint_unicode(stdout, __fmt, __args); }
134
135 inline void
136 vprint_nonunicode(string_view __fmt, format_args __args)
137 { std::vprint_nonunicode(stdout, __fmt, __args); }
138
139 // Defined for C++26, supported as an extension to C++23.
140 inline void println(FILE* __stream)
141 {
142#if defined(_WIN32) && !defined(__CYGWIN__)
143 if constexpr (__unicode::__literal_encoding_is_utf8())
144 std::vprint_unicode(__stream, "\n", std::make_format_args());
145 else
146#endif
147 if (std::putc(c: '\n', __stream) == EOF)
148 __throw_system_error(EIO);
149 }
150
151 inline void println() { std::println(stdout); }
152
153_GLIBCXX_END_NAMESPACE_VERSION
154} // namespace std
155#endif // __cpp_lib_print
156#endif // _GLIBCXX_PRINT
157