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, 2009 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 streambuf.tcc
27  * This is an internal header file, included by other library headers.
28  * You should not attempt to use it directly.
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 _GLIBCXX_BEGIN_NAMESPACE(std)
41 
42  template<typename _CharT, typename _Traits>
44  basic_streambuf<_CharT, _Traits>::
45  xsgetn(char_type* __s, streamsize __n)
46  {
47  streamsize __ret = 0;
48  while (__ret < __n)
49  {
50  const streamsize __buf_len = this->egptr() - this->gptr();
51  if (__buf_len)
52  {
53  const streamsize __remaining = __n - __ret;
54  const streamsize __len = std::min(__buf_len, __remaining);
55  traits_type::copy(__s, this->gptr(), __len);
56  __ret += __len;
57  __s += __len;
58  this->gbump(__len);
59  }
60 
61  if (__ret < __n)
62  {
63  const int_type __c = this->uflow();
64  if (!traits_type::eq_int_type(__c, traits_type::eof()))
65  {
66  traits_type::assign(*__s++, traits_type::to_char_type(__c));
67  ++__ret;
68  }
69  else
70  break;
71  }
72  }
73  return __ret;
74  }
75 
76  template<typename _CharT, typename _Traits>
79  xsputn(const char_type* __s, streamsize __n)
80  {
81  streamsize __ret = 0;
82  while (__ret < __n)
83  {
84  const streamsize __buf_len = this->epptr() - this->pptr();
85  if (__buf_len)
86  {
87  const streamsize __remaining = __n - __ret;
88  const streamsize __len = std::min(__buf_len, __remaining);
89  traits_type::copy(this->pptr(), __s, __len);
90  __ret += __len;
91  __s += __len;
92  this->pbump(__len);
93  }
94 
95  if (__ret < __n)
96  {
97  int_type __c = this->overflow(traits_type::to_int_type(*__s));
98  if (!traits_type::eq_int_type(__c, traits_type::eof()))
99  {
100  ++__ret;
101  ++__s;
102  }
103  else
104  break;
105  }
106  }
107  return __ret;
108  }
109 
110  // Conceivably, this could be used to implement buffer-to-buffer
111  // copies, if this was ever desired in an un-ambiguous way by the
112  // standard.
113  template<typename _CharT, typename _Traits>
114  streamsize
115  __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
117  bool& __ineof)
118  {
119  streamsize __ret = 0;
120  __ineof = true;
121  typename _Traits::int_type __c = __sbin->sgetc();
122  while (!_Traits::eq_int_type(__c, _Traits::eof()))
123  {
124  __c = __sbout->sputc(_Traits::to_char_type(__c));
125  if (_Traits::eq_int_type(__c, _Traits::eof()))
126  {
127  __ineof = false;
128  break;
129  }
130  ++__ret;
131  __c = __sbin->snextc();
132  }
133  return __ret;
134  }
135 
136  template<typename _CharT, typename _Traits>
137  inline streamsize
138  __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
139  basic_streambuf<_CharT, _Traits>* __sbout)
140  {
141  bool __ineof;
142  return __copy_streambufs_eof(__sbin, __sbout, __ineof);
143  }
144 
145  // Inhibit implicit instantiations for required instantiations,
146  // which are defined via explicit instantiations elsewhere.
147  // NB: This syntax is a GNU extension.
148 #if _GLIBCXX_EXTERN_TEMPLATE
149  extern template class basic_streambuf<char>;
150  extern template
151  streamsize
152  __copy_streambufs(basic_streambuf<char>*,
153  basic_streambuf<char>*);
154  extern template
155  streamsize
156  __copy_streambufs_eof(basic_streambuf<char>*,
157  basic_streambuf<char>*, bool&);
158 
159 #ifdef _GLIBCXX_USE_WCHAR_T
160  extern template class basic_streambuf<wchar_t>;
161  extern template
162  streamsize
163  __copy_streambufs(basic_streambuf<wchar_t>*,
164  basic_streambuf<wchar_t>*);
165  extern template
166  streamsize
167  __copy_streambufs_eof(basic_streambuf<wchar_t>*,
168  basic_streambuf<wchar_t>*, bool&);
169 #endif
170 #endif
171 
172 _GLIBCXX_END_NAMESPACE
173 
174 #endif
ptrdiff_t streamsize
Integral type for I/O operation counts and buffer sizes.
Definition: postypes.h:98
The actual work of input and output (interface).
Definition: iosfwd:50
int_type sgetc()
Getting the next character.
Definition: streambuf:315
int_type sputc(char_type __c)
Entry point for all single-character output functions.
Definition: streambuf:400
const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:186
traits_type::int_type int_type
Definition: streambuf:125
int_type snextc()
Getting the next character.
Definition: streambuf:275