1 // String based streams -*- C++ -*-
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 // 2006, 2007, 2008, 2009, 2010, 2011
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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
19 // permissions described in the GCC Runtime Library Exception, version
20 // 3.1, as published by the Free Software Foundation.
22 // You should have received a copy of the GNU General Public License and
23 // a copy of the GCC Runtime Library Exception along with this program;
24 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
25 // <http://www.gnu.org/licenses/>.
27 /** @file bits/sstream.tcc
28 * This is an internal header file, included by other library headers.
29 * Do not attempt to use it directly. @headername{sstream}
33 // ISO C++ 14882: 27.7 String-based streams
37 #define _SSTREAM_TCC 1
39 #pragma GCC system_header
41 namespace std _GLIBCXX_VISIBILITY(default)
43 _GLIBCXX_BEGIN_NAMESPACE_VERSION
45 template <class _CharT, class _Traits, class _Alloc>
46 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
47 basic_stringbuf<_CharT, _Traits, _Alloc>::
48 pbackfail(int_type __c)
50 int_type __ret = traits_type::eof();
51 if (this->eback() < this->gptr())
53 // Try to put back __c into input sequence in one of three ways.
54 // Order these tests done in is unspecified by the standard.
55 const bool __testeof = traits_type::eq_int_type(__c, __ret);
58 const bool __testeq = traits_type::eq(traits_type::
61 const bool __testout = this->_M_mode & ios_base::out;
62 if (__testeq || __testout)
66 *this->gptr() = traits_type::to_char_type(__c);
73 __ret = traits_type::not_eof(__c);
79 template <class _CharT, class _Traits, class _Alloc>
80 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
81 basic_stringbuf<_CharT, _Traits, _Alloc>::
82 overflow(int_type __c)
84 const bool __testout = this->_M_mode & ios_base::out;
85 if (__builtin_expect(!__testout, false))
86 return traits_type::eof();
88 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
89 if (__builtin_expect(__testeof, false))
90 return traits_type::not_eof(__c);
92 const __size_type __capacity = _M_string.capacity();
93 const __size_type __max_size = _M_string.max_size();
94 const bool __testput = this->pptr() < this->epptr();
95 if (__builtin_expect(!__testput && __capacity == __max_size, false))
96 return traits_type::eof();
98 // Try to append __c into output sequence in one of two ways.
99 // Order these tests done in is unspecified by the standard.
100 const char_type __conv = traits_type::to_char_type(__c);
103 // NB: Start ostringstream buffers at 512 chars. This is an
104 // experimental value (pronounced "arbitrary" in some of the
105 // hipper English-speaking countries), and can be changed to
106 // suit particular needs.
108 // _GLIBCXX_RESOLVE_LIB_DEFECTS
109 // 169. Bad efficiency of overflow() mandated
110 // 432. stringbuf::overflow() makes only one write position
112 const __size_type __opt_len = std::max(__size_type(2 * __capacity),
114 const __size_type __len = std::min(__opt_len, __max_size);
116 __tmp.reserve(__len);
118 __tmp.assign(this->pbase(), this->epptr() - this->pbase());
119 __tmp.push_back(__conv);
120 _M_string.swap(__tmp);
121 _M_sync(const_cast<char_type*>(_M_string.data()),
122 this->gptr() - this->eback(), this->pptr() - this->pbase());
125 *this->pptr() = __conv;
130 template <class _CharT, class _Traits, class _Alloc>
131 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
132 basic_stringbuf<_CharT, _Traits, _Alloc>::
135 int_type __ret = traits_type::eof();
136 const bool __testin = this->_M_mode & ios_base::in;
139 // Update egptr() to match the actual string end.
142 if (this->gptr() < this->egptr())
143 __ret = traits_type::to_int_type(*this->gptr());
148 template <class _CharT, class _Traits, class _Alloc>
149 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
150 basic_stringbuf<_CharT, _Traits, _Alloc>::
151 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
153 pos_type __ret = pos_type(off_type(-1));
154 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
155 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
156 const bool __testboth = __testin && __testout && __way != ios_base::cur;
157 __testin &= !(__mode & ios_base::out);
158 __testout &= !(__mode & ios_base::in);
160 // _GLIBCXX_RESOLVE_LIB_DEFECTS
161 // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
162 const char_type* __beg = __testin ? this->eback() : this->pbase();
163 if ((__beg || !__off) && (__testin || __testout || __testboth))
167 off_type __newoffi = __off;
168 off_type __newoffo = __newoffi;
169 if (__way == ios_base::cur)
171 __newoffi += this->gptr() - __beg;
172 __newoffo += this->pptr() - __beg;
174 else if (__way == ios_base::end)
175 __newoffo = __newoffi += this->egptr() - __beg;
177 if ((__testin || __testboth)
179 && this->egptr() - __beg >= __newoffi)
181 this->setg(this->eback(), this->eback() + __newoffi,
183 __ret = pos_type(__newoffi);
185 if ((__testout || __testboth)
187 && this->egptr() - __beg >= __newoffo)
189 _M_pbump(this->pbase(), this->epptr(), __newoffo);
190 __ret = pos_type(__newoffo);
196 template <class _CharT, class _Traits, class _Alloc>
197 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
198 basic_stringbuf<_CharT, _Traits, _Alloc>::
199 seekpos(pos_type __sp, ios_base::openmode __mode)
201 pos_type __ret = pos_type(off_type(-1));
202 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
203 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
205 const char_type* __beg = __testin ? this->eback() : this->pbase();
206 if ((__beg || !off_type(__sp)) && (__testin || __testout))
210 const off_type __pos(__sp);
211 const bool __testpos = (0 <= __pos
212 && __pos <= this->egptr() - __beg);
216 this->setg(this->eback(), this->eback() + __pos,
219 _M_pbump(this->pbase(), this->epptr(), __pos);
226 template <class _CharT, class _Traits, class _Alloc>
228 basic_stringbuf<_CharT, _Traits, _Alloc>::
229 _M_sync(char_type* __base, __size_type __i, __size_type __o)
231 const bool __testin = _M_mode & ios_base::in;
232 const bool __testout = _M_mode & ios_base::out;
233 char_type* __endg = __base + _M_string.size();
234 char_type* __endp = __base + _M_string.capacity();
236 if (__base != _M_string.data())
238 // setbuf: __i == size of buffer area (_M_string.size() == 0).
245 this->setg(__base, __base + __i, __endg);
248 _M_pbump(__base, __endp, __o);
249 // egptr() always tracks the string end. When !__testin,
250 // for the correct functioning of the streambuf inlines
251 // the other get area pointers are identical.
253 this->setg(__endg, __endg, __endg);
257 template <class _CharT, class _Traits, class _Alloc>
259 basic_stringbuf<_CharT, _Traits, _Alloc>::
260 _M_pbump(char_type* __pbeg, char_type* __pend, off_type __off)
262 this->setp(__pbeg, __pend);
263 while (__off > __gnu_cxx::__numeric_traits<int>::__max)
265 this->pbump(__gnu_cxx::__numeric_traits<int>::__max);
266 __off -= __gnu_cxx::__numeric_traits<int>::__max;
271 // Inhibit implicit instantiations for required instantiations,
272 // which are defined via explicit instantiations elsewhere.
273 #if _GLIBCXX_EXTERN_TEMPLATE
274 extern template class basic_stringbuf<char>;
275 extern template class basic_istringstream<char>;
276 extern template class basic_ostringstream<char>;
277 extern template class basic_stringstream<char>;
279 #ifdef _GLIBCXX_USE_WCHAR_T
280 extern template class basic_stringbuf<wchar_t>;
281 extern template class basic_istringstream<wchar_t>;
282 extern template class basic_ostringstream<wchar_t>;
283 extern template class basic_stringstream<wchar_t>;
287 _GLIBCXX_END_NAMESPACE_VERSION