print
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// <print> Print functions -*- C++ -*-
// Copyright The GNU Toolchain Authors.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/print
* This is a Standard C++ Library header.
*/
#ifndef _GLIBCXX_PRINT
#define _GLIBCXX_PRINT 1
#ifdef _GLIBCXX_SYSHDR
#pragma GCC system_header
#endif
#include <bits/requires_hosted.h> // for std::format
#define __glibcxx_want_print
#include <bits/version.h>
#ifdef __cpp_lib_print // C++ >= 23
#include <format>
#include <cstdio>
#include <cerrno>
#include <bits/functexcept.h>
#ifdef _WIN32
# include <system_error>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
inline void
vprint_nonunicode(FILE* __stream, string_view __fmt, format_args __args)
{
__format::_Str_sink<char> __buf;
std::vformat_to(__buf.out(), __fmt, __args);
auto __out = __buf.view();
if (std::fwrite(__out.data(), 1, __out.size(), __stream) != __out.size())
__throw_system_error(EIO);
}
inline void
vprint_unicode(FILE* __stream, string_view __fmt, format_args __args)
{
#if !defined(_WIN32) || defined(__CYGWIN__)
// For most targets we don't need to do anything special to write
// Unicode to a terminal.
std::vprint_nonunicode(__stream, __fmt, __args);
#else
__format::_Str_sink<char> __buf;
std::vformat_to(__buf.out(), __fmt, __args);
auto __out = __buf.view();
void* __open_terminal(FILE*);
error_code __write_to_terminal(void*, span<char>);
// If stream refers to a terminal, write a native Unicode string to it.
if (auto __term = __open_terminal(__stream))
{
string __out = std::vformat(__fmt, __args);
error_code __e;
if (!std::fflush(__stream))
{
__e = __write_to_terminal(__term, __out);
if (!__e)
return;
if (__e == std::make_error_code(errc::illegal_byte_sequence))
return;
}
else
__e = error_code(errno, generic_category());
_GLIBCXX_THROW_OR_ABORT(system_error(__e, "std::vprint_unicode"));
}
// Otherwise just write the string to the file as vprint_nonunicode does.
if (std::fwrite(__out.data(), 1, __out.size(), __stream) != __out.size())
__throw_system_error(EIO);
#endif
}
template<typename... _Args>
inline void
print(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args)
{
auto __fmtargs = std::make_format_args(__args...);
if constexpr (__unicode::__literal_encoding_is_utf8())
std::vprint_unicode(__stream, __fmt.get(), __fmtargs);
else
std::vprint_nonunicode(__stream, __fmt.get(), __fmtargs);
}
template<typename... _Args>
inline void
print(format_string<_Args...> __fmt, _Args&&... __args)
{ std::print(stdout, __fmt, std::forward<_Args>(__args)...); }
template<typename... _Args>
inline void
println(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args)
{
std::print(__stream, "{}\n",
std::format(__fmt, std::forward<_Args>(__args)...));
}
template<typename... _Args>
inline void
println(format_string<_Args...> __fmt, _Args&&... __args)
{ std::println(stdout, __fmt, std::forward<_Args>(__args)...); }
inline void
vprint_unicode(string_view __fmt, format_args __args)
{ std::vprint_unicode(stdout, __fmt, __args); }
inline void
vprint_nonunicode(string_view __fmt, format_args __args)
{ std::vprint_nonunicode(stdout, __fmt, __args); }
// Defined for C++26, supported as an extension to C++23.
inline void println(FILE* __stream)
{
#if defined(_WIN32) && !defined(__CYGWIN__)
if constexpr (__unicode::__literal_encoding_is_utf8())
std::vprint_unicode(__stream, "\n", std::make_format_args());
else
#endif
if (std::putc('\n', __stream) == EOF)
__throw_system_error(EIO);
}
inline void println() { std::println(stdout); }
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // __cpp_lib_print
#endif // _GLIBCXX_PRINT
format
system_error
cerrno
cstdio
functexcept.h
version.h
requires_hosted.h
std::_V2::generic_category
const error_category & generic_category() noexcept
Error category for errno error codes.
std::make_error_code
error_code make_error_code(future_errc __errc) noexcept
Overload of make_error_code for future_errc.
Definition future:96
std::forward
constexpr _Tp && forward(typename std::remove_reference< _Tp >::type &__t) noexcept
Forward an lvalue.
Definition move.h:72
std
ISO C++ entities toplevel namespace is std.
std::error_code
Definition system_error:226
std::system_error
An exception type that includes an error_code value.
Definition system_error:559