1 // Stream buffer classes -*- C++ -*-
2 
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
4 // 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 2, 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 // You should have received a copy of the GNU General Public License along
18 // with this library; see the file COPYING.  If not, write to the Free
19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
20 // USA.
21 
22 // As a special exception, you may use this file as part of a free software
23 // library without restriction.  Specifically, if other files instantiate
24 // templates or use macros or inline functions from this file, or you compile
25 // this file and link it with other files to produce an executable, this
26 // file does not by itself cause the resulting executable to be covered by
27 // the GNU General Public License.  This exception does not however
28 // invalidate any other reasons why the executable file might be covered by
29 // the GNU General Public License.
30 
31 //
32 // ISO C++ 14882: 27.5  Stream buffers
33 //
34 
35 #ifndef _CPP_BITS_STREAMBUF_TCC
36 #define _CPP_BITS_STREAMBUF_TCC 1
37 
38 #pragma GCC system_header
39 
40 namespace std
41 {
42   template<typename _CharT, typename _Traits>
43     const size_t
44     basic_streambuf<_CharT, _Traits>::_S_pback_size;
45 
46   template<typename _CharT, typename _Traits>
47     typename basic_streambuf<_CharT, _Traits>::int_type
48     basic_streambuf<_CharT, _Traits>::
49     sbumpc()
50     {
51       int_type __ret;
52       if (_M_in_cur && _M_in_cur < _M_in_end)
53 	{
54 	  char_type __c = *(this->gptr());
55 	  _M_in_cur_move(1);
56 	  __ret = traits_type::to_int_type(__c);
57 	}
58       else
59 	__ret = this->uflow();
60       return __ret;
61     }
62 
63   template<typename _CharT, typename _Traits>
64     typename basic_streambuf<_CharT, _Traits>::int_type
65     basic_streambuf<_CharT, _Traits>::
66     sputbackc(char_type __c)
67     {
68       int_type __ret;
69       bool __testpos = _M_in_cur && _M_in_beg < _M_in_cur;
70       if (!__testpos || !traits_type::eq(__c, this->gptr()[-1]))
71 	__ret = this->pbackfail(traits_type::to_int_type(__c));
72       else
73 	{
74 	  _M_in_cur_move(-1);
75 	  __ret = traits_type::to_int_type(*this->gptr());
76 	}
77       return __ret;
78     }
79 
80   template<typename _CharT, typename _Traits>
81     typename basic_streambuf<_CharT, _Traits>::int_type
82     basic_streambuf<_CharT, _Traits>::
83     sungetc()
84     {
85       int_type __ret;
86       if (_M_in_cur && _M_in_beg < _M_in_cur)
87 	{
88 	  _M_in_cur_move(-1);
89 	  __ret = traits_type::to_int_type(*_M_in_cur);
90 	}
91       else
92 	__ret = this->pbackfail();
93       return __ret;
94     }
95 
96   // Don't test against _M_buf + _M_buf_size, because _M_buf reflects
97   // allocated space, and on certain (rare but entirely legal)
98   // situations, there will be no allocated space yet the internal
99   // buffers will still be valid. (This happens if setp is used to set
100   // the internal buffer to say some externally-allocated sequence.)
101   template<typename _CharT, typename _Traits>
102     typename basic_streambuf<_CharT, _Traits>::int_type
103     basic_streambuf<_CharT, _Traits>::
104     sputc(char_type __c)
105     {
106       int_type __ret;
107       if (_M_out_buf_size())
108 	{
109 	  *_M_out_cur = __c;
110 	  _M_out_cur_move(1);
111 	  __ret = traits_type::to_int_type(__c);
112 	}
113       else
114 	__ret = this->overflow(traits_type::to_int_type(__c));
115       return __ret;
116     }
117 
118   template<typename _CharT, typename _Traits>
119     streamsize
120     basic_streambuf<_CharT, _Traits>::
121     xsgetn(char_type* __s, streamsize __n)
122     {
123       streamsize __ret = 0;
124       while (__ret < __n)
125 	{
126 	  size_t __buf_len = _M_in_end - _M_in_cur;
127 	  if (__buf_len > 0)
128 	    {
129 	      size_t __remaining = __n - __ret;
130 	      size_t __len = min(__buf_len, __remaining);
131 	      traits_type::copy(__s, _M_in_cur, __len);
132 	      __ret += __len;
133 	      __s += __len;
134 	      _M_in_cur_move(__len);
135 	    }
136 
137 	  if (__ret < __n)
138 	    {
139 	      int_type __c = this->uflow();
140 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
141 		{
142 		  traits_type::assign(*__s++, traits_type::to_char_type(__c));
143 		  ++__ret;
144 		}
145 	      else
146 		break;
147 	    }
148 	}
149       return __ret;
150     }
151 
152   // Don't test against _M_buf + _M_buf_size, because _M_buf reflects
153   // allocated space, and on certain (rare but entirely legal)
154   // situations, there will be no allocated space yet the internal
155   // buffers will still be valid. (This happens if setp is used to set
156   // the internal buffer to say some externally-allocated sequence.)
157   template<typename _CharT, typename _Traits>
158     streamsize
159     basic_streambuf<_CharT, _Traits>::
160     xsputn(const char_type* __s, streamsize __n)
161     {
162       streamsize __ret = 0;
163       while (__ret < __n)
164 	{
165 	  off_type __buf_len = _M_out_buf_size();
166 	  if (__buf_len > 0)
167 	    {
168 	      off_type __remaining = __n - __ret;
169 	      off_type __len = min(__buf_len, __remaining);
170 	      traits_type::copy(_M_out_cur, __s, __len);
171 	      __ret += __len;
172 	      __s += __len;
173 	      _M_out_cur_move(__len);
174 	    }
175 
176 	  if (__ret < __n)
177 	    {
178 	      int_type __c = this->overflow(traits_type::to_int_type(*__s));
179 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
180 		{
181 		  ++__ret;
182 		  ++__s;
183 		}
184 	      else
185 		break;
186 	    }
187 	}
188       return __ret;
189     }
190 
191   // Conceivably, this could be used to implement buffer-to-buffer
192   // copies, if this was ever desired in an un-ambiguous way by the
193   // standard. If so, then checks for __ios being zero would be
194   // necessary.
195   template<typename _CharT, typename _Traits>
196     streamsize
197     __copy_streambufs(basic_ios<_CharT, _Traits>& __ios,
198 		      basic_streambuf<_CharT, _Traits>* __sbin,
199 		      basic_streambuf<_CharT, _Traits>* __sbout)
200   {
201     streamsize __ret = 0;
202     try
203       {
204 	typename _Traits::int_type __c = __sbin->sgetc();
205 	while (!_Traits::eq_int_type(__c, _Traits::eof()))
206 	  {
207 	    const size_t __n = __sbin->_M_in_end - __sbin->_M_in_cur;
208 	    if (__n > 1)
209 	      {
210 		const size_t __wrote = __sbout->sputn(__sbin->_M_in_cur,
211 						      __n);
212 		__sbin->_M_in_cur_move(__wrote);
213 		__ret += __wrote;
214 		if (__wrote < __n)
215 		  break;
216 		__c = __sbin->underflow();
217 	      }
218 	    else
219 	      {
220 		__c = __sbout->sputc(_Traits::to_char_type(__c));
221 		if (_Traits::eq_int_type(__c, _Traits::eof()))
222 		  break;
223 		++__ret;
224 		__c = __sbin->snextc();
225 	      }
226 	  }
227       }
228     catch(exception& __fail)
229       {
230 	__ios.setstate(ios_base::failbit);
231 	if ((__ios.exceptions() & ios_base::failbit) != 0)
232 	  __throw_exception_again;
233       }
234     return __ret;
235   }
236 
237   // Inhibit implicit instantiations for required instantiations,
238   // which are defined via explicit instantiations elsewhere.
239   // NB:  This syntax is a GNU extension.
240 #if _GLIBCPP_EXTERN_TEMPLATE
241   extern template class basic_streambuf<char>;
242   extern template
243     streamsize
244     __copy_streambufs(basic_ios<char>&, basic_streambuf<char>*,
245 		      basic_streambuf<char>*);
246 
247 #ifdef _GLIBCPP_USE_WCHAR_T
248   extern template class basic_streambuf<wchar_t>;
249   extern template
250     streamsize
251     __copy_streambufs(basic_ios<wchar_t>&, basic_streambuf<wchar_t>*,
252 		      basic_streambuf<wchar_t>*);
253 #endif
254 #endif
255 } // namespace std
256 
257 #endif
258