1 // String based streams -*- 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 sstream.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: 27.7 String-based streams
38 //
39
40 #ifndef _SSTREAM_TCC
41 #define _SSTREAM_TCC 1
42
43 #pragma GCC system_header
44
45 #include <sstream>
46
_GLIBCXX_BEGIN_NAMESPACE(std)47 _GLIBCXX_BEGIN_NAMESPACE(std)
48
49 template <class _CharT, class _Traits, class _Alloc>
50 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
51 basic_stringbuf<_CharT, _Traits, _Alloc>::
52 pbackfail(int_type __c)
53 {
54 int_type __ret = traits_type::eof();
55 if (this->eback() < this->gptr())
56 {
57 // Try to put back __c into input sequence in one of three ways.
58 // Order these tests done in is unspecified by the standard.
59 const bool __testeof = traits_type::eq_int_type(__c, __ret);
60 if (!__testeof)
61 {
62 const bool __testeq = traits_type::eq(traits_type::
63 to_char_type(__c),
64 this->gptr()[-1]);
65 const bool __testout = this->_M_mode & ios_base::out;
66 if (__testeq || __testout)
67 {
68 this->gbump(-1);
69 if (!__testeq)
70 *this->gptr() = traits_type::to_char_type(__c);
71 __ret = __c;
72 }
73 }
74 else
75 {
76 this->gbump(-1);
77 __ret = traits_type::not_eof(__c);
78 }
79 }
80 return __ret;
81 }
82
83 template <class _CharT, class _Traits, class _Alloc>
84 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
85 basic_stringbuf<_CharT, _Traits, _Alloc>::
overflow(int_type __c)86 overflow(int_type __c)
87 {
88 const bool __testout = this->_M_mode & ios_base::out;
89 if (__builtin_expect(!__testout, false))
90 return traits_type::eof();
91
92 const bool __testeof = traits_type::eq_int_type(__c, traits_type::eof());
93 if (__builtin_expect(__testeof, false))
94 return traits_type::not_eof(__c);
95
96 const __size_type __capacity = _M_string.capacity();
97 const __size_type __max_size = _M_string.max_size();
98 const bool __testput = this->pptr() < this->epptr();
99 if (__builtin_expect(!__testput && __capacity == __max_size, false))
100 return traits_type::eof();
101
102 // Try to append __c into output sequence in one of two ways.
103 // Order these tests done in is unspecified by the standard.
104 const char_type __conv = traits_type::to_char_type(__c);
105 if (!__testput)
106 {
107 // NB: Start ostringstream buffers at 512 chars. This is an
108 // experimental value (pronounced "arbitrary" in some of the
109 // hipper english-speaking countries), and can be changed to
110 // suit particular needs.
111 //
112 // _GLIBCXX_RESOLVE_LIB_DEFECTS
113 // 169. Bad efficiency of overflow() mandated
114 // 432. stringbuf::overflow() makes only one write position
115 // available
116 const __size_type __opt_len = std::max(__size_type(2 * __capacity),
117 __size_type(512));
118 const __size_type __len = std::min(__opt_len, __max_size);
119 __string_type __tmp;
120 __tmp.reserve(__len);
121 if (this->pbase())
122 __tmp.assign(this->pbase(), this->epptr() - this->pbase());
123 __tmp.push_back(__conv);
124 _M_string.swap(__tmp);
125 _M_sync(const_cast<char_type*>(_M_string.data()),
126 this->gptr() - this->eback(), this->pptr() - this->pbase());
127 }
128 else
129 *this->pptr() = __conv;
130 this->pbump(1);
131 return __c;
132 }
133
134 template <class _CharT, class _Traits, class _Alloc>
135 typename basic_stringbuf<_CharT, _Traits, _Alloc>::int_type
136 basic_stringbuf<_CharT, _Traits, _Alloc>::
underflow()137 underflow()
138 {
139 int_type __ret = traits_type::eof();
140 const bool __testin = this->_M_mode & ios_base::in;
141 if (__testin)
142 {
143 // Update egptr() to match the actual string end.
144 _M_update_egptr();
145
146 if (this->gptr() < this->egptr())
147 __ret = traits_type::to_int_type(*this->gptr());
148 }
149 return __ret;
150 }
151
152 template <class _CharT, class _Traits, class _Alloc>
153 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
154 basic_stringbuf<_CharT, _Traits, _Alloc>::
seekoff(off_type __off,ios_base::seekdir __way,ios_base::openmode __mode)155 seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __mode)
156 {
157 pos_type __ret = pos_type(off_type(-1));
158 bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
159 bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
160 const bool __testboth = __testin && __testout && __way != ios_base::cur;
161 __testin &= !(__mode & ios_base::out);
162 __testout &= !(__mode & ios_base::in);
163
164 // _GLIBCXX_RESOLVE_LIB_DEFECTS
165 // 453. basic_stringbuf::seekoff need not always fail for an empty stream.
166 const char_type* __beg = __testin ? this->eback() : this->pbase();
167 if ((__beg || !__off) && (__testin || __testout || __testboth))
168 {
169 _M_update_egptr();
170
171 off_type __newoffi = __off;
172 off_type __newoffo = __newoffi;
173 if (__way == ios_base::cur)
174 {
175 __newoffi += this->gptr() - __beg;
176 __newoffo += this->pptr() - __beg;
177 }
178 else if (__way == ios_base::end)
179 __newoffo = __newoffi += this->egptr() - __beg;
180
181 if ((__testin || __testboth)
182 && __newoffi >= 0
183 && this->egptr() - __beg >= __newoffi)
184 {
185 this->gbump((__beg + __newoffi) - this->gptr());
186 __ret = pos_type(__newoffi);
187 }
188 if ((__testout || __testboth)
189 && __newoffo >= 0
190 && this->egptr() - __beg >= __newoffo)
191 {
192 this->pbump((__beg + __newoffo) - this->pptr());
193 __ret = pos_type(__newoffo);
194 }
195 }
196 return __ret;
197 }
198
199 template <class _CharT, class _Traits, class _Alloc>
200 typename basic_stringbuf<_CharT, _Traits, _Alloc>::pos_type
201 basic_stringbuf<_CharT, _Traits, _Alloc>::
seekpos(pos_type __sp,ios_base::openmode __mode)202 seekpos(pos_type __sp, ios_base::openmode __mode)
203 {
204 pos_type __ret = pos_type(off_type(-1));
205 const bool __testin = (ios_base::in & this->_M_mode & __mode) != 0;
206 const bool __testout = (ios_base::out & this->_M_mode & __mode) != 0;
207
208 const char_type* __beg = __testin ? this->eback() : this->pbase();
209 if ((__beg || !off_type(__sp)) && (__testin || __testout))
210 {
211 _M_update_egptr();
212
213 const off_type __pos(__sp);
214 const bool __testpos = (0 <= __pos
215 && __pos <= this->egptr() - __beg);
216 if (__testpos)
217 {
218 if (__testin)
219 this->gbump((__beg + __pos) - this->gptr());
220 if (__testout)
221 this->pbump((__beg + __pos) - this->pptr());
222 __ret = __sp;
223 }
224 }
225 return __ret;
226 }
227
228 template <class _CharT, class _Traits, class _Alloc>
229 void
230 basic_stringbuf<_CharT, _Traits, _Alloc>::
_M_sync(char_type * __base,__size_type __i,__size_type __o)231 _M_sync(char_type* __base, __size_type __i, __size_type __o)
232 {
233 const bool __testin = _M_mode & ios_base::in;
234 const bool __testout = _M_mode & ios_base::out;
235 char_type* __endg = __base + _M_string.size();
236 char_type* __endp = __base + _M_string.capacity();
237
238 if (__base != _M_string.data())
239 {
240 // setbuf: __i == size of buffer area (_M_string.size() == 0).
241 __endg += __i;
242 __i = 0;
243 __endp = __endg;
244 }
245
246 if (__testin)
247 this->setg(__base, __base + __i, __endg);
248 if (__testout)
249 {
250 this->setp(__base, __endp);
251 this->pbump(__o);
252 // egptr() always tracks the string end. When !__testin,
253 // for the correct functioning of the streambuf inlines
254 // the other get area pointers are identical.
255 if (!__testin)
256 this->setg(__endg, __endg, __endg);
257 }
258 }
259
260 // Inhibit implicit instantiations for required instantiations,
261 // which are defined via explicit instantiations elsewhere.
262 // NB: This syntax is a GNU extension.
263 #if _GLIBCXX_EXTERN_TEMPLATE
264 extern template class basic_stringbuf<char>;
265 extern template class basic_istringstream<char>;
266 extern template class basic_ostringstream<char>;
267 extern template class basic_stringstream<char>;
268
269 #ifdef _GLIBCXX_USE_WCHAR_T
270 extern template class basic_stringbuf<wchar_t>;
271 extern template class basic_istringstream<wchar_t>;
272 extern template class basic_ostringstream<wchar_t>;
273 extern template class basic_stringstream<wchar_t>;
274 #endif
275 #endif
276
277 _GLIBCXX_END_NAMESPACE
278
279 #endif
280