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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._M_span();
 
    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