1 // String based streams -*- C++ -*-
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
5 // Free Software Foundation, Inc.
7 // This file is part of the GNU ISO C++ Library. This library is free
8 // software; you can redistribute it and/or modify it under the
9 // terms of the GNU General Public License as published by the
10 // Free Software Foundation; either version 2, or (at your option)
13 // This library is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License along
19 // with this library; see the file COPYING. If not, write to the Free
20 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
23 // As a special exception, you may use this file as part of a free software
24 // library without restriction. Specifically, if other files instantiate
25 // templates or use macros or inline functions from this file, or you compile
26 // this file and link it with other files to produce an executable, this
27 // file does not by itself cause the resulting executable to be covered by
28 // the GNU General Public License. This exception does not however
29 // invalidate any other reasons why the executable file might be covered by
30 // the GNU General Public License.
33 * This is an internal header file, included by other library headers.
34 * You should not attempt to use it directly.
38 // ISO C++ 14882: 27.7 String-based streams
42 #define _SSTREAM_TCC 1
44 #pragma GCC system_header
46 _GLIBCXX_BEGIN_NAMESPACE(std)
48 template <class _CharT, class _Traits, class _Alloc>
49 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
50 basic_stringbuf<_CharT, _Traits, _Alloc>::
51 pbackfail(int_type __c)
53 int_type __ret = traits_type::eof();
54 if (this->eback() < this->gptr())
56 // Try to put back __c into input sequence in one of three ways.
57 // Order these tests done in is unspecified by the standard.
58 const bool __testeof = traits_type::eq_int_type(__c, __ret);
61 const bool __testeq = traits_type::eq(traits_type::
64 const bool __testout = this->_M_mode & ios_base::out;
65 if (__testeq || __testout)
69 *this->gptr() = traits_type::to_char_type(__c);
76 __ret = traits_type::not_eof(__c);
82 template <class _CharT, class _Traits, class _Alloc>
83 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
84 basic_stringbuf<_CharT, _Traits, _Alloc>::
85 overflow(int_type __c)
87 const bool __testout = this->_M_mode & ios_base::out;
88 if (__builtin_expect(!__testout, false))
89 return traits_type::eof();
91 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
92 if (__builtin_expect(__testeof, false))
93 return traits_type::not_eof(__c);
95 const __size_type __capacity = _M_string.capacity();
96 const __size_type __max_size = _M_string.max_size();
97 const bool __testput = this->pptr() < this->epptr();
98 if (__builtin_expect(!__testput && __capacity == __max_size, false))
99 return traits_type::eof();
101 // Try to append __c into output sequence in one of two ways.
102 // Order these tests done in is unspecified by the standard.
103 const char_type __conv = traits_type::to_char_type(__c);
106 // NB: Start ostringstream buffers at 512 chars. This is an
107 // experimental value (pronounced "arbitrary" in some of the
108 // hipper English-speaking countries), and can be changed to
109 // suit particular needs.
111 // _GLIBCXX_RESOLVE_LIB_DEFECTS
112 // 169. Bad efficiency of overflow() mandated
113 // 432. stringbuf::overflow() makes only one write position
115 const __size_type __opt_len = std::max(__size_type(2 * __capacity),
117 const __size_type __len = std::min(__opt_len, __max_size);
119 __tmp.reserve(__len);
121 __tmp.assign(this->pbase(), this->epptr() - this->pbase());
122 __tmp.push_back(__conv);
123 _M_string.swap(__tmp);
124 _M_sync(const_cast<char_type*>(_M_string.data()),
125 this->gptr() - this->eback(), this->pptr() - this->pbase());
128 *this->pptr() = __conv;
133 template <class _CharT, class _Traits, class _Alloc>
134 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
135 basic_stringbuf<_CharT, _Traits, _Alloc>::
138 int_type __ret = traits_type::eof();
139 const bool __testin = this->_M_mode & ios_base::in;
142 // Update egptr() to match the actual string end.
145 if (this->gptr() < this->egptr())
146 __ret = traits_type::to_int_type(*this->gptr());
151 template <class _CharT, class _Traits, class _Alloc>
152 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
153 basic_stringbuf<_CharT, _Traits, _Alloc>::
154 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
156 pos_type __ret = pos_type(off_type(-1));
157 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
158 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
159 const bool __testboth = __testin && __testout && __way != ios_base::cur;
160 __testin &= !(__mode & ios_base::out);
161 __testout &= !(__mode & ios_base::in);
163 // _GLIBCXX_RESOLVE_LIB_DEFECTS
164 // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
165 const char_type* __beg = __testin ? this->eback() : this->pbase();
166 if ((__beg || !__off) && (__testin || __testout || __testboth))
170 off_type __newoffi = __off;
171 off_type __newoffo = __newoffi;
172 if (__way == ios_base::cur)
174 __newoffi += this->gptr() - __beg;
175 __newoffo += this->pptr() - __beg;
177 else if (__way == ios_base::end)
178 __newoffo = __newoffi += this->egptr() - __beg;
180 if ((__testin || __testboth)
182 && this->egptr() - __beg >= __newoffi)
184 this->gbump((__beg + __newoffi) - this->gptr());
185 __ret = pos_type(__newoffi);
187 if ((__testout || __testboth)
189 && this->egptr() - __beg >= __newoffo)
191 this->pbump((__beg + __newoffo) - this->pptr());
192 __ret = pos_type(__newoffo);
198 template <class _CharT, class _Traits, class _Alloc>
199 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
200 basic_stringbuf<_CharT, _Traits, _Alloc>::
201 seekpos(pos_type __sp, ios_base::openmode __mode)
203 pos_type __ret = pos_type(off_type(-1));
204 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
205 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
207 const char_type* __beg = __testin ? this->eback() : this->pbase();
208 if ((__beg || !off_type(__sp)) && (__testin || __testout))
212 const off_type __pos(__sp);
213 const bool __testpos = (0 <= __pos
214 && __pos <= this->egptr() - __beg);
218 this->gbump((__beg + __pos) - this->gptr());
220 this->pbump((__beg + __pos) - this->pptr());
227 template <class _CharT, class _Traits, class _Alloc>
229 basic_stringbuf<_CharT, _Traits, _Alloc>::
230 _M_sync(char_type* __base, __size_type __i, __size_type __o)
232 const bool __testin = _M_mode & ios_base::in;
233 const bool __testout = _M_mode & ios_base::out;
234 char_type* __endg = __base + _M_string.size();
235 char_type* __endp = __base + _M_string.capacity();
237 if (__base != _M_string.data())
239 // setbuf: __i == size of buffer area (_M_string.size() == 0).
246 this->setg(__base, __base + __i, __endg);
249 this->setp(__base, __endp);
251 // egptr() always tracks the string end. When !__testin,
252 // for the correct functioning of the streambuf inlines
253 // the other get area pointers are identical.
255 this->setg(__endg, __endg, __endg);
259 // Inhibit implicit instantiations for required instantiations,
260 // which are defined via explicit instantiations elsewhere.
261 // NB: This syntax is a GNU extension.
262 #if _GLIBCXX_EXTERN_TEMPLATE
263 extern template class basic_stringbuf<char>;
264 extern template class basic_istringstream<char>;
265 extern template class basic_ostringstream<char>;
266 extern template class basic_stringstream<char>;
268 #ifdef _GLIBCXX_USE_WCHAR_T
269 extern template class basic_stringbuf<wchar_t>;
270 extern template class basic_istringstream<wchar_t>;
271 extern template class basic_ostringstream<wchar_t>;
272 extern template class basic_stringstream<wchar_t>;
276 _GLIBCXX_END_NAMESPACE