1 // Stream buffer classes -*- C++ -*-
2 
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
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, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
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 /** @file streambuf.tcc
32  *  This is an internal header file, included by other library headers.
33  *  You should not attempt to use it directly.
34  */
35 
36 //
37 // ISO C++ 14882: 27.5  Stream buffers
38 //
39 
40 #ifndef _STREAMBUF_TCC
41 #define _STREAMBUF_TCC 1
42 
43 #pragma GCC system_header
44 
45 _GLIBCXX_BEGIN_NAMESPACE(std)
46 
47   template<typename _CharT, typename _Traits>
48     streamsize
49     basic_streambuf<_CharT, _Traits>::
50     xsgetn(char_type* __s, streamsize __n)
51     {
52       streamsize __ret = 0;
53       while (__ret < __n)
54 	{
55 	  const streamsize __buf_len = this->egptr() - this->gptr();
56 	  if (__buf_len)
57 	    {
58 	      const streamsize __remaining = __n - __ret;
59 	      const streamsize __len = std::min(__buf_len, __remaining);
60 	      traits_type::copy(__s, this->gptr(), __len);
61 	      __ret += __len;
62 	      __s += __len;
63 	      this->gbump(__len);
64 	    }
65 
66 	  if (__ret < __n)
67 	    {
68 	      const int_type __c = this->uflow();
69 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
70 		{
71 		  traits_type::assign(*__s++, traits_type::to_char_type(__c));
72 		  ++__ret;
73 		}
74 	      else
75 		break;
76 	    }
77 	}
78       return __ret;
79     }
80 
81   template<typename _CharT, typename _Traits>
82     streamsize
83     basic_streambuf<_CharT, _Traits>::
84     xsputn(const char_type* __s, streamsize __n)
85     {
86       streamsize __ret = 0;
87       while (__ret < __n)
88 	{
89 	  const streamsize __buf_len = this->epptr() - this->pptr();
90 	  if (__buf_len)
91 	    {
92 	      const streamsize __remaining = __n - __ret;
93 	      const streamsize __len = std::min(__buf_len, __remaining);
94 	      traits_type::copy(this->pptr(), __s, __len);
95 	      __ret += __len;
96 	      __s += __len;
97 	      this->pbump(__len);
98 	    }
99 
100 	  if (__ret < __n)
101 	    {
102 	      int_type __c = this->overflow(traits_type::to_int_type(*__s));
103 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
104 		{
105 		  ++__ret;
106 		  ++__s;
107 		}
108 	      else
109 		break;
110 	    }
111 	}
112       return __ret;
113     }
114 
115   // Conceivably, this could be used to implement buffer-to-buffer
116   // copies, if this was ever desired in an un-ambiguous way by the
117   // standard.
118   template<typename _CharT, typename _Traits>
119     streamsize
120     __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
121 			  basic_streambuf<_CharT, _Traits>* __sbout,
122 			  bool& __ineof)
123     {
124       streamsize __ret = 0;
125       __ineof = true;
126       typename _Traits::int_type __c = __sbin->sgetc();
127       while (!_Traits::eq_int_type(__c, _Traits::eof()))
128 	{
129 	  __c = __sbout->sputc(_Traits::to_char_type(__c));
130 	  if (_Traits::eq_int_type(__c, _Traits::eof()))
131 	    {
132 	      __ineof = false;
133 	      break;
134 	    }
135 	  ++__ret;
136 	  __c = __sbin->snextc();
137 	}
138       return __ret;
139     }
140 
141   template<typename _CharT, typename _Traits>
142     inline streamsize
143     __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
144 		      basic_streambuf<_CharT, _Traits>* __sbout)
145     {
146       bool __ineof;
147       return __copy_streambufs_eof(__sbin, __sbout, __ineof);
148     }
149 
150   // Inhibit implicit instantiations for required instantiations,
151   // which are defined via explicit instantiations elsewhere.
152   // NB:  This syntax is a GNU extension.
153 #if _GLIBCXX_EXTERN_TEMPLATE
154   extern template class basic_streambuf<char>;
155   extern template
156     streamsize
157     __copy_streambufs(basic_streambuf<char>*,
158 		      basic_streambuf<char>*);
159   extern template
160     streamsize
161     __copy_streambufs_eof(basic_streambuf<char>*,
162 			  basic_streambuf<char>*, bool&);
163 
164 #ifdef _GLIBCXX_USE_WCHAR_T
165   extern template class basic_streambuf<wchar_t>;
166   extern template
167     streamsize
168     __copy_streambufs(basic_streambuf<wchar_t>*,
169 		      basic_streambuf<wchar_t>*);
170   extern template
171     streamsize
172     __copy_streambufs_eof(basic_streambuf<wchar_t>*,
173 			  basic_streambuf<wchar_t>*, bool&);
174 #endif
175 #endif
176 
177 _GLIBCXX_END_NAMESPACE
178 
179 #endif
180