1 // Stream buffer classes -*- C++ -*-
2 
3 // Copyright (C) 1997-2017 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/streambuf.tcc
26  *  This is an internal header file, included by other library headers.
27  *  Do not attempt to use it directly. @headername{streambuf}
28  */
29 
30 //
31 // ISO C++ 14882: 27.5  Stream buffers
32 //
33 
34 #ifndef _STREAMBUF_TCC
35 #define _STREAMBUF_TCC 1
36 
37 #pragma GCC system_header
38 
39 namespace std _GLIBCXX_VISIBILITY(default)
40 {
41 _GLIBCXX_BEGIN_NAMESPACE_VERSION
42 
43   template<typename _CharT, typename _Traits>
44     streamsize
45     basic_streambuf<_CharT, _Traits>::
xsgetn(char_type * __s,streamsize __n)46     xsgetn(char_type* __s, streamsize __n)
47     {
48       streamsize __ret = 0;
49       while (__ret < __n)
50 	{
51 	  const streamsize __buf_len = this->egptr() - this->gptr();
52 	  if (__buf_len)
53 	    {
54 	      const streamsize __remaining = __n - __ret;
55 	      const streamsize __len = std::min(__buf_len, __remaining);
56 	      traits_type::copy(__s, this->gptr(), __len);
57 	      __ret += __len;
58 	      __s += __len;
59 	      this->__safe_gbump(__len);
60 	    }
61 
62 	  if (__ret < __n)
63 	    {
64 	      const int_type __c = this->uflow();
65 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
66 		{
67 		  traits_type::assign(*__s++, traits_type::to_char_type(__c));
68 		  ++__ret;
69 		}
70 	      else
71 		break;
72 	    }
73 	}
74       return __ret;
75     }
76 
77   template<typename _CharT, typename _Traits>
78     streamsize
79     basic_streambuf<_CharT, _Traits>::
xsputn(const char_type * __s,streamsize __n)80     xsputn(const char_type* __s, streamsize __n)
81     {
82       streamsize __ret = 0;
83       while (__ret < __n)
84 	{
85 	  const streamsize __buf_len = this->epptr() - this->pptr();
86 	  if (__buf_len)
87 	    {
88 	      const streamsize __remaining = __n - __ret;
89 	      const streamsize __len = std::min(__buf_len, __remaining);
90 	      traits_type::copy(this->pptr(), __s, __len);
91 	      __ret += __len;
92 	      __s += __len;
93 	      this->__safe_pbump(__len);
94 	    }
95 
96 	  if (__ret < __n)
97 	    {
98 	      int_type __c = this->overflow(traits_type::to_int_type(*__s));
99 	      if (!traits_type::eq_int_type(__c, traits_type::eof()))
100 		{
101 		  ++__ret;
102 		  ++__s;
103 		}
104 	      else
105 		break;
106 	    }
107 	}
108       return __ret;
109     }
110 
111   // Conceivably, this could be used to implement buffer-to-buffer
112   // copies, if this was ever desired in an un-ambiguous way by the
113   // standard.
114   template<typename _CharT, typename _Traits>
115     streamsize
__copy_streambufs_eof(basic_streambuf<_CharT,_Traits> * __sbin,basic_streambuf<_CharT,_Traits> * __sbout,bool & __ineof)116     __copy_streambufs_eof(basic_streambuf<_CharT, _Traits>* __sbin,
117 			  basic_streambuf<_CharT, _Traits>* __sbout,
118 			  bool& __ineof)
119     {
120       streamsize __ret = 0;
121       __ineof = true;
122       typename _Traits::int_type __c = __sbin->sgetc();
123       while (!_Traits::eq_int_type(__c, _Traits::eof()))
124 	{
125 	  __c = __sbout->sputc(_Traits::to_char_type(__c));
126 	  if (_Traits::eq_int_type(__c, _Traits::eof()))
127 	    {
128 	      __ineof = false;
129 	      break;
130 	    }
131 	  ++__ret;
132 	  __c = __sbin->snextc();
133 	}
134       return __ret;
135     }
136 
137   template<typename _CharT, typename _Traits>
138     inline streamsize
__copy_streambufs(basic_streambuf<_CharT,_Traits> * __sbin,basic_streambuf<_CharT,_Traits> * __sbout)139     __copy_streambufs(basic_streambuf<_CharT, _Traits>* __sbin,
140 		      basic_streambuf<_CharT, _Traits>* __sbout)
141     {
142       bool __ineof;
143       return __copy_streambufs_eof(__sbin, __sbout, __ineof);
144     }
145 
146   // Inhibit implicit instantiations for required instantiations,
147   // which are defined via explicit instantiations elsewhere.
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_VERSION
173 } // namespace std
174 
175 #endif
176