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> // format_args (TODO: move to bits/formatfwd.h?)
#include <cstdio> // FILE, EOF, putc
#include <cerrno> // EACCES, EIO
#include <bits/functexcept.h> // __throw_system_error
#ifdef _WIN32
# include <system_error>
#endif
#ifndef _GLIBCXX_NO_INLINE_PRINT
# include <bits/print.h>
#endif
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
void
vprint_nonunicode(FILE* __stream, string_view __fmt, format_args __args);
void
vprint_nonunicode_buffered(FILE* __stream, string_view __fmt,
format_args __args);
void
vprint_unicode(FILE* __stream, string_view __fmt, format_args __args);
void
vprint_unicode_buffered(FILE* __stream, string_view __fmt,
format_args __args);
void
vprint_unicode_buffered(string_view __fmt, format_args __args);
void
vprint_nonunicode_buffered(string_view __fmt, format_args __args);
template<typename... _Args>
inline void
print(FILE* __stream, format_string<_Args...> __fmt, _Args&&... __args)
{
constexpr bool __locksafe =
(enable_nonlocking_formatter_optimization<remove_cvref_t<_Args>> && ...);
auto __fmtargs = std::make_format_args(__args...);
#if defined(_WIN32) && !defined(__CYGWIN__)
if constexpr (__unicode::__literal_encoding_is_utf8())
std::vprint_unicode_buffered(__stream, __fmt.get(), __fmtargs);
else
#endif
if constexpr (__locksafe)
std::vprint_nonunicode(__stream, __fmt.get(), __fmtargs);
else
std::vprint_nonunicode_buffered(__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)
{
constexpr bool __locksafe =
(enable_nonlocking_formatter_optimization<remove_cvref_t<_Args>> && ...);
// The standard wants us to call
// print(stream, dynamic_format(string(fmt.get()) + '\n'), args...)
// here, but we can avoid that string concatenation in most cases,
// and we know what that would call, so we can call that directly.
auto __fmtargs = std::make_format_args(__args...);
#if defined(_WIN32) && !defined(__CYGWIN__)
if constexpr (__unicode::__literal_encoding_is_utf8())
{
// We can't avoid the string concatenation here, but we can call
// vprint_unicode_buffered directly, since that's what print would do.
string __fmtn;
__fmtn.reserve(__fmt.get().size() + 1);
__fmtn = __fmt.get();
__fmtn += '\n';
std::vprint_unicode_buffered(__stream, __fmtn, __fmtargs);
}
else
#endif
#ifdef _GLIBCXX_NO_INLINE_PRINT
{
string __fmtn;
__fmtn.reserve(__fmt.get().size() + 1);
__fmtn = __fmt.get();
__fmtn += '\n';
std::vprint_nonunicode(__stream, __fmtn, __fmtargs);
}
#else
// For non-Windows and for non-Unicode on Windows, we know that print
// would call vprint_nonunicode or vprint_nonunicode_buffered with a
// newline appended to the format-string. Use a _File_sink that adds
// the newline automatically and write to it directly.
if constexpr (__locksafe)
std::vformat_to(__format::_File_sink(__stream, true).out(),
__fmt.get(), __fmtargs);
else
{
// Format to a string buffer first, then write the result to a
// _File_sink that adds a newline.
__format::_Str_sink<char> __buf;
std::vformat_to(__buf.out(), __fmt.get(), __fmtargs);
string_view __s(__buf.view());
__format::_File_sink(__stream, true).out() = __s;
}
#endif
}
template<typename... _Args>
inline void
println(format_string<_Args...> __fmt, _Args&&... __args)
{ std::println(stdout, __fmt, std::forward<_Args>(__args)...); }
inline void
vprint_unicode_buffered(string_view __fmt, format_args __args)
{ std::vprint_unicode_buffered(stdout, __fmt, __args); }
inline void
vprint_nonunicode_buffered(string_view __fmt, format_args __args)
{ std::vprint_nonunicode_buffered(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_buffered(__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
print.h
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.