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

   1 // Helpers for ostream inserters -*- C++ -*-
   2
   3 // Copyright (C) 2007, 2008, 2009 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 <cxxabi-forced.h>
  37
  38 _GLIBCXX_BEGIN_NAMESPACE(std)
  39
  40   template<typename _CharT, typename _Traits>
  41     inline void
  42     __ostream_write(basic_ostream<_CharT, _Traits>& __out,
  43                     const _CharT* __s, streamsize __n)
  44     {
  45       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  46       typedef typename __ostream_type::ios_base    __ios_base;
  47
  48       const streamsize __put = __out.rdbuf()->sputn(__s, __n);
  49       if (__put != __n)
  50         __out.setstate(__ios_base::badbit);
  51     }
  52
  53   template<typename _CharT, typename _Traits>
  54     inline void
  55     __ostream_fill(basic_ostream<_CharT, _Traits>& __out, streamsize __n)
  56     {
  57       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  58       typedef typename __ostream_type::ios_base    __ios_base;
  59
  60       const _CharT __c = __out.fill();
  61       for (; __n > 0; --__n)
  62         {
  63           const typename _Traits::int_type __put = __out.rdbuf()->sputc(__c);
  64           if (_Traits::eq_int_type(__put, _Traits::eof()))
  65             {
  66               __out.setstate(__ios_base::badbit);
  67               break;
  68             }
  69         }
  70     }
  71
  72   template<typename _CharT, typename _Traits>
  73     basic_ostream<_CharT, _Traits>&
  74     __ostream_insert(basic_ostream<_CharT, _Traits>& __out,
  75                      const _CharT* __s, streamsize __n)
  76     {
  77       typedef basic_ostream<_CharT, _Traits>       __ostream_type;
  78       typedef typename __ostream_type::ios_base    __ios_base;
  79
  80       typename __ostream_type::sentry __cerb(__out);
  81       if (__cerb)
  82         {
  83           __try
  84             {
  85               const streamsize __w = __out.width();
  86               if (__w > __n)
  87                 {
  88                   const bool __left = ((__out.flags()
  89                                         & __ios_base::adjustfield)
  90                                        == __ios_base::left);
  91                   if (!__left)
  92                     __ostream_fill(__out, __w - __n);
  93                   if (__out.good())
  94                     __ostream_write(__out, __s, __n);
  95                   if (__left && __out.good())
  96                     __ostream_fill(__out, __w - __n);
  97                 }
  98               else
  99                 __ostream_write(__out, __s, __n);
 100               __out.width(0);
 101             }
 102           __catch(__cxxabiv1::__forced_unwind&)
 103             {
 104               __out._M_setstate(__ios_base::badbit);
 105               __throw_exception_again;
 106             }
 107           __catch(...)
 108             { __out._M_setstate(__ios_base::badbit); }
 109         }
 110       return __out;
 111     }
 112
 113   // Inhibit implicit instantiations for required instantiations,
 114   // which are defined via explicit instantiations elsewhere.
 115   // NB:  This syntax is a GNU extension.
 116 #if _GLIBCXX_EXTERN_TEMPLATE
 117   extern template ostream& __ostream_insert(ostream&, const char*, streamsize);
 118
 119 #ifdef _GLIBCXX_USE_WCHAR_T
 120   extern template wostream& __ostream_insert(wostream&, const wchar_t*,
 121                                              streamsize);
 122 #endif
 123 #endif
 124
 125 _GLIBCXX_END_NAMESPACE
 126
 127 #endif /* _OSTREAM_INSERT_H */