libstdc++
streambuf.tcc
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1 // Stream buffer classes -*- C++ -*-
2 
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 // 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
5 //
6 // This file is part of the GNU ISO C++ Library. This library is free
7 // software; you can redistribute it and/or modify it under the
8 // terms of the GNU General Public License as published by the
9 // Free Software Foundation; either version 3, or (at your option)
10 // any later version.
11 
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
16 
17 // Under Section 7 of GPL version 3, you are granted additional
18 // permissions described in the GCC Runtime Library Exception, version
19 // 3.1, as published by the Free Software Foundation.
20 
21 // You should have received a copy of the GNU General Public License and
22 // a copy of the GCC Runtime Library Exception along with this program;
23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 // <http://www.gnu.org/licenses/>.
25 
26 /** @file bits/streambuf.tcc
27  * This is an internal header file, included by other library headers.
28  * Do not attempt to use it directly. @headername{streambuf}
29  */
30 
31 //
32 // ISO C++ 14882: 27.5 Stream buffers
33 //
34 
35 #ifndef _STREAMBUF_TCC
36 #define _STREAMBUF_TCC 1
37 
38 #pragma GCC system_header
39 
40 namespace std _GLIBCXX_VISIBILITY(default)
41 {
42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 
44  template<typename _CharT, typename _Traits>
48  {
49  streamsize __ret = 0;
50  while (__ret < __n)
51  {
52  const streamsize __buf_len = this->egptr() - this->gptr();
53  if (__buf_len)
54  {
55  const streamsize __remaining = __n - __ret;
56  const streamsize __len = std::min(__buf_len, __remaining);
57  traits_type::copy(__s, this->gptr(), __len);
58  __ret += __len;
59  __s += __len;
60  this->__safe_gbump(__len);
61  }
62 
63  if (__ret < __n)
64  {
65  const int_type __c = this->uflow();
66  if (!traits_type::eq_int_type(__c, traits_type::eof()))
67  {
68  traits_type::assign(*__s++, traits_type::to_char_type(__c));
69  ++__ret;
70  }
71  else
72  break;
73  }
74  }
75  return __ret;
76  }
77 
78  template<typename _CharT, typename _Traits>
81  xsputn(const char_type* __s, streamsize __n)
82  {
83  streamsize __ret = 0;
84  while (__ret < __n)
85  {
86  const streamsize __buf_len = this->epptr() - this->pptr();
87  if (__buf_len)
88  {
89  const streamsize __remaining = __n - __ret;
90  const streamsize __len = std::min(__buf_len, __remaining);
91  traits_type::copy(this->pptr(), __s, __len);
92  __ret += __len;
93  __s += __len;
94  this->__safe_pbump(__len);
95  }
96 
97  if (__ret < __n)
98  {
99  int_type __c = this->overflow(traits_type::to_int_type(*__s));
100  if (!traits_type::eq_int_type(__c, traits_type::eof()))
101  {
102  ++__ret;
103  ++__s;
104  }
105  else
106  break;
107  }
108  }
109  return __ret;
110  }
111 
112  // Conceivably, this could be used to implement buffer-to-buffer
113  // copies, if this was ever desired in an un-ambiguous way by the
114  // standard.
115  template<typename _CharT, typename _Traits>
116  streamsize
117  __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
119  bool& __ineof)
120  {
121  streamsize __ret = 0;
122  __ineof = true;
123  typename _Traits::int_type __c = __sbin->sgetc();
124  while (!_Traits::eq_int_type(__c, _Traits::eof()))
125  {
126  __c = __sbout->sputc(_Traits::to_char_type(__c));
127  if (_Traits::eq_int_type(__c, _Traits::eof()))
128  {
129  __ineof = false;
130  break;
131  }
132  ++__ret;
133  __c = __sbin->snextc();
134  }
135  return __ret;
136  }
137 
138  template<typename _CharT, typename _Traits>
139  inline streamsize
140  __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
141  basic_streambuf<_CharT, _Traits>* __sbout)
142  {
143  bool __ineof;
144  return __copy_streambufs_eof(__sbin, __sbout, __ineof);
145  }
146 
147  // Inhibit implicit instantiations for required instantiations,
148  // which are defined via explicit instantiations elsewhere.
149 #if _GLIBCXX_EXTERN_TEMPLATE
150  extern template class basic_streambuf<char>;
151  extern template
152  streamsize
153  __copy_streambufs(basic_streambuf<char>*,
154  basic_streambuf<char>*);
155  extern template
156  streamsize
157  __copy_streambufs_eof(basic_streambuf<char>*,
158  basic_streambuf<char>*, bool&);
159 
160 #ifdef _GLIBCXX_USE_WCHAR_T
161  extern template class basic_streambuf<wchar_t>;
162  extern template
163  streamsize
164  __copy_streambufs(basic_streambuf<wchar_t>*,
165  basic_streambuf<wchar_t>*);
166  extern template
167  streamsize
168  __copy_streambufs_eof(basic_streambuf<wchar_t>*,
169  basic_streambuf<wchar_t>*, bool&);
170 #endif
171 #endif
172 
173 _GLIBCXX_END_NAMESPACE_VERSION
174 } // namespace std
175 
176 #endif
int_type sgetc()
Getting the next character.
Definition: streambuf:317
virtual streamsize xsgetn(char_type *__s, streamsize __n)
Multiple character extraction.
Definition: streambuf.tcc:47
int_type sputc(char_type __c)
Entry point for all single-character output functions.
Definition: streambuf:403
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:100
virtual streamsize xsputn(const char_type *__s, streamsize __n)
Multiple character insertion.
Definition: streambuf.tcc:81
traits_type::int_type int_type
Definition: streambuf:128
The actual work of input and output (interface).This is a base class. Derived stream buffers each con...
Definition: iosfwd:82
const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:187
int_type snextc()
Getting the next character.
Definition: streambuf:277