libstdc++-v3/include/bits/ostream_insert.h

   1 // Helpers for ostream inserters -*- C++ -*-
   2
   3 // Copyright (C) 2007-2020 Free Software Foundation, Inc.
   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 bits/ostream_insert.h
  26  *  This is an internal header file, included by other library headers.
  27  *  Do not attempt to use it directly. @headername{ostream}
  28  */
  29
  30 #ifndef _OSTREAM_INSERT_H
  31 #define _OSTREAM_INSERT_H 1
  32
  33 #pragma GCC system_header
  34
  35 #include <iosfwd>
  36 #include <bits/cxxabi_forced.h>
  37
  38 namespace std _GLIBCXX_VISIBILITY(default)
  39 {
  40 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  41
  42   template<typename _CharT, typename _Traits>
  43     inline void
  44     __ostream_write(basic_ostream<_CharT, _Traits>& __out,
  45                     const _CharT* __s, streamsize __n)
  46     {
  47       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  48       typedef typename __ostream_type::ios_base    __ios_base;
  49
  50       const streamsize __put = __out.rdbuf()->sputn(__s, __n);
  51       if (__put != __n)
  52         __out.setstate(__ios_base::badbit);
  53     }
  54
  55   template<typename _CharT, typename _Traits>
  56     inline void
  57     __ostream_fill(basic_ostream<_CharT, _Traits>& __out, streamsize __n)
  58     {
  59       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  60       typedef typename __ostream_type::ios_base    __ios_base;
  61
  62       const _CharT __c = __out.fill();
  63       for (; __n > 0; --__n)
  64         {
  65           const typename _Traits::int_type __put = __out.rdbuf()->sputc(__c);
  66           if (_Traits::eq_int_type(__put, _Traits::eof()))
  67             {
  68               __out.setstate(__ios_base::badbit);
  69               break;
  70             }
  71         }
  72     }
  73
  74   template<typename _CharT, typename _Traits>
  75     basic_ostream<_CharT, _Traits>&
  76     __ostream_insert(basic_ostream<_CharT, _Traits>& __out,
  77                      const _CharT* __s, streamsize __n)
  78     {
  79       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  80       typedef typename __ostream_type::ios_base    __ios_base;
  81
  82       typename __ostream_type::sentry __cerb(__out);
  83       if (__cerb)
  84         {
  85           __try
  86             {
  87               const streamsize __w = __out.width();
  88               if (__w > __n)
  89                 {
  90                   const bool __left = ((__out.flags()
  91                                         & __ios_base::adjustfield)
  92                                        == __ios_base::left);
  93                   if (!__left)
  94                     __ostream_fill(__out, __w - __n);
  95                   if (__out.good())
  96                     __ostream_write(__out, __s, __n);
  97                   if (__left && __out.good())
  98                     __ostream_fill(__out, __w - __n);
  99                 }
 100               else
 101                 __ostream_write(__out, __s, __n);
 102               __out.width(0);
 103             }
 104           __catch(__cxxabiv1::__forced_unwind&)
 105             {
 106               __out._M_setstate(__ios_base::badbit);
 107               __throw_exception_again;
 108             }
 109           __catch(...)
 110             { __out._M_setstate(__ios_base::badbit); }
 111         }
 112       return __out;
 113     }
 114
 115   // Inhibit implicit instantiations for required instantiations,
 116   // which are defined via explicit instantiations elsewhere.
 117 #if _GLIBCXX_EXTERN_TEMPLATE
 118   extern template ostream& __ostream_insert(ostream&, const char*, streamsize);
 119
 120 #ifdef _GLIBCXX_USE_WCHAR_T
 121   extern template wostream& __ostream_insert(wostream&, const wchar_t*,
 122                                              streamsize);
 123 #endif
 124 #endif
 125
 126 _GLIBCXX_END_NAMESPACE_VERSION
 127 } // namespace std
 128
 129 #endif /* _OSTREAM_INSERT_H */