1 // Streambuf iterators
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_iterator.h
32 * This is an internal header file, included by other library headers.
33 * You should not attempt to use it directly.
34 */
35
36 #ifndef _STREAMBUF_ITERATOR_H
37 #define _STREAMBUF_ITERATOR_H 1
38
39 #pragma GCC system_header
40
41 #include <streambuf>
42 #include <debug/debug.h>
43
_GLIBCXX_BEGIN_NAMESPACE(std)44 _GLIBCXX_BEGIN_NAMESPACE(std)
45
46 // 24.5.3 Template class istreambuf_iterator
47 /// Provides input iterator semantics for streambufs.
48 template<typename _CharT, typename _Traits>
49 class istreambuf_iterator
50 : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type,
51 _CharT*, _CharT&>
52 {
53 public:
54 // Types:
55 //@{
56 /// Public typedefs
57 typedef _CharT char_type;
58 typedef _Traits traits_type;
59 typedef typename _Traits::int_type int_type;
60 typedef basic_streambuf<_CharT, _Traits> streambuf_type;
61 typedef basic_istream<_CharT, _Traits> istream_type;
62 //@}
63
64 template<typename _CharT2>
65 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
66 ostreambuf_iterator<_CharT2> >::__type
67 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
68 ostreambuf_iterator<_CharT2>);
69
70 template<typename _CharT2>
71 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
72 _CharT2*>::__type
73 __copy_aux(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
74 _CharT2*);
75
76 template<typename _CharT2>
77 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
78 istreambuf_iterator<_CharT2> >::__type
79 find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
80 const _CharT2&);
81
82 private:
83 // 24.5.3 istreambuf_iterator
84 // p 1
85 // If the end of stream is reached (streambuf_type::sgetc()
86 // returns traits_type::eof()), the iterator becomes equal to
87 // the "end of stream" iterator value.
88 // NB: This implementation assumes the "end of stream" value
89 // is EOF, or -1.
90 mutable streambuf_type* _M_sbuf;
91 mutable int_type _M_c;
92
93 public:
94 /// Construct end of input stream iterator.
95 istreambuf_iterator() throw()
96 : _M_sbuf(0), _M_c(traits_type::eof()) { }
97
98 /// Construct start of input stream iterator.
99 istreambuf_iterator(istream_type& __s) throw()
100 : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { }
101
102 /// Construct start of streambuf iterator.
103 istreambuf_iterator(streambuf_type* __s) throw()
104 : _M_sbuf(__s), _M_c(traits_type::eof()) { }
105
106 /// Return the current character pointed to by iterator. This returns
107 /// streambuf.sgetc(). It cannot be assigned. NB: The result of
108 /// operator*() on an end of stream is undefined.
109 char_type
110 operator*() const
111 {
112 #ifdef _GLIBCXX_DEBUG_PEDANTIC
113 // Dereferencing a past-the-end istreambuf_iterator is a
114 // libstdc++ extension
115 __glibcxx_requires_cond(!_M_at_eof(),
116 _M_message(__gnu_debug::__msg_deref_istreambuf)
117 ._M_iterator(*this));
118 #endif
119 return traits_type::to_char_type(_M_get());
120 }
121
122 /// Advance the iterator. Calls streambuf.sbumpc().
123 istreambuf_iterator&
124 operator++()
125 {
126 __glibcxx_requires_cond(!_M_at_eof(),
127 _M_message(__gnu_debug::__msg_inc_istreambuf)
128 ._M_iterator(*this));
129 if (_M_sbuf)
130 {
131 _M_sbuf->sbumpc();
132 _M_c = traits_type::eof();
133 }
134 return *this;
135 }
136
137 /// Advance the iterator. Calls streambuf.sbumpc().
138 istreambuf_iterator
139 operator++(int)
140 {
141 __glibcxx_requires_cond(!_M_at_eof(),
142 _M_message(__gnu_debug::__msg_inc_istreambuf)
143 ._M_iterator(*this));
144
145 istreambuf_iterator __old = *this;
146 if (_M_sbuf)
147 {
148 __old._M_c = _M_sbuf->sbumpc();
149 _M_c = traits_type::eof();
150 }
151 return __old;
152 }
153
154 // _GLIBCXX_RESOLVE_LIB_DEFECTS
155 // 110 istreambuf_iterator::equal not const
156 // NB: there is also number 111 (NAD, Future) pending on this function.
157 /// Return true both iterators are end or both are not end.
158 bool
159 equal(const istreambuf_iterator& __b) const
160 {
161 const bool __thiseof = _M_at_eof();
162 const bool __beof = __b._M_at_eof();
163 return (__thiseof && __beof || (!__thiseof && !__beof));
164 }
165
166 private:
167 int_type
168 _M_get() const
169 {
170 const int_type __eof = traits_type::eof();
171 int_type __ret = __eof;
172 if (_M_sbuf)
173 {
174 if (!traits_type::eq_int_type(_M_c, __eof))
175 __ret = _M_c;
176 else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()),
177 __eof))
178 _M_c = __ret;
179 else
180 _M_sbuf = 0;
181 }
182 return __ret;
183 }
184
185 bool
186 _M_at_eof() const
187 {
188 const int_type __eof = traits_type::eof();
189 return traits_type::eq_int_type(_M_get(), __eof);
190 }
191 };
192
193 template<typename _CharT, typename _Traits>
194 inline bool
195 operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
196 const istreambuf_iterator<_CharT, _Traits>& __b)
197 { return __a.equal(__b); }
198
199 template<typename _CharT, typename _Traits>
200 inline bool
201 operator!=(const istreambuf_iterator<_CharT, _Traits>& __a,
202 const istreambuf_iterator<_CharT, _Traits>& __b)
203 { return !__a.equal(__b); }
204
205 /// Provides output iterator semantics for streambufs.
206 template<typename _CharT, typename _Traits>
207 class ostreambuf_iterator
208 : public iterator<output_iterator_tag, void, void, void, void>
209 {
210 public:
211 // Types:
212 //@{
213 /// Public typedefs
214 typedef _CharT char_type;
215 typedef _Traits traits_type;
216 typedef basic_streambuf<_CharT, _Traits> streambuf_type;
217 typedef basic_ostream<_CharT, _Traits> ostream_type;
218 //@}
219
220 template<typename _CharT2>
221 friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
222 ostreambuf_iterator<_CharT2> >::__type
223 copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
224 ostreambuf_iterator<_CharT2>);
225
226 private:
227 streambuf_type* _M_sbuf;
228 bool _M_failed;
229
230 public:
231 /// Construct output iterator from ostream.
ostreambuf_iterator(ostream_type & __s)232 ostreambuf_iterator(ostream_type& __s) throw ()
233 : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { }
234
235 /// Construct output iterator from streambuf.
throw()236 ostreambuf_iterator(streambuf_type* __s) throw ()
237 : _M_sbuf(__s), _M_failed(!_M_sbuf) { }
238
239 /// Write character to streambuf. Calls streambuf.sputc().
240 ostreambuf_iterator&
241 operator=(_CharT __c)
242 {
243 if (!_M_failed &&
244 _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof()))
245 _M_failed = true;
246 return *this;
247 }
248
249 /// Return *this.
250 ostreambuf_iterator&
251 operator*()
252 { return *this; }
253
254 /// Return *this.
255 ostreambuf_iterator&
256 operator++(int)
257 { return *this; }
258
259 /// Return *this.
260 ostreambuf_iterator&
261 operator++()
262 { return *this; }
263
264 /// Return true if previous operator=() failed.
265 bool
failed()266 failed() const throw()
267 { return _M_failed; }
268
269 ostreambuf_iterator&
_M_put(const _CharT * __ws,streamsize __len)270 _M_put(const _CharT* __ws, streamsize __len)
271 {
272 if (__builtin_expect(!_M_failed, true)
273 && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len,
274 false))
275 _M_failed = true;
276 return *this;
277 }
278 };
279
280 // Overloads for streambuf iterators.
281 template<typename _CharT>
282 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
283 ostreambuf_iterator<_CharT> >::__type
copy(istreambuf_iterator<_CharT> __first,istreambuf_iterator<_CharT> __last,ostreambuf_iterator<_CharT> __result)284 copy(istreambuf_iterator<_CharT> __first,
285 istreambuf_iterator<_CharT> __last,
286 ostreambuf_iterator<_CharT> __result)
287 {
288 if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed)
289 {
290 bool __ineof;
291 __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof);
292 if (!__ineof)
293 __result._M_failed = true;
294 }
295 return __result;
296 }
297
298 template<typename _CharT>
299 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
300 ostreambuf_iterator<_CharT> >::__type
__copy_aux(_CharT * __first,_CharT * __last,ostreambuf_iterator<_CharT> __result)301 __copy_aux(_CharT* __first, _CharT* __last,
302 ostreambuf_iterator<_CharT> __result)
303 {
304 const streamsize __num = __last - __first;
305 if (__num > 0)
306 __result._M_put(__first, __num);
307 return __result;
308 }
309
310 template<typename _CharT>
311 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
312 ostreambuf_iterator<_CharT> >::__type
__copy_aux(const _CharT * __first,const _CharT * __last,ostreambuf_iterator<_CharT> __result)313 __copy_aux(const _CharT* __first, const _CharT* __last,
314 ostreambuf_iterator<_CharT> __result)
315 {
316 const streamsize __num = __last - __first;
317 if (__num > 0)
318 __result._M_put(__first, __num);
319 return __result;
320 }
321
322 template<typename _CharT>
323 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
324 _CharT*>::__type
__copy_aux(istreambuf_iterator<_CharT> __first,istreambuf_iterator<_CharT> __last,_CharT * __result)325 __copy_aux(istreambuf_iterator<_CharT> __first,
326 istreambuf_iterator<_CharT> __last, _CharT* __result)
327 {
328 typedef istreambuf_iterator<_CharT> __is_iterator_type;
329 typedef typename __is_iterator_type::traits_type traits_type;
330 typedef typename __is_iterator_type::streambuf_type streambuf_type;
331 typedef typename traits_type::int_type int_type;
332
333 if (__first._M_sbuf && !__last._M_sbuf)
334 {
335 streambuf_type* __sb = __first._M_sbuf;
336 int_type __c = __sb->sgetc();
337 while (!traits_type::eq_int_type(__c, traits_type::eof()))
338 {
339 const streamsize __n = __sb->egptr() - __sb->gptr();
340 if (__n > 1)
341 {
342 traits_type::copy(__result, __sb->gptr(), __n);
343 __sb->gbump(__n);
344 __result += __n;
345 __c = __sb->underflow();
346 }
347 else
348 {
349 *__result++ = traits_type::to_char_type(__c);
350 __c = __sb->snextc();
351 }
352 }
353 }
354 return __result;
355 }
356
357 template<typename _CharT>
358 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
359 istreambuf_iterator<_CharT> >::__type
find(istreambuf_iterator<_CharT> __first,istreambuf_iterator<_CharT> __last,const _CharT & __val)360 find(istreambuf_iterator<_CharT> __first,
361 istreambuf_iterator<_CharT> __last, const _CharT& __val)
362 {
363 typedef istreambuf_iterator<_CharT> __is_iterator_type;
364 typedef typename __is_iterator_type::traits_type traits_type;
365 typedef typename __is_iterator_type::streambuf_type streambuf_type;
366 typedef typename traits_type::int_type int_type;
367
368 if (__first._M_sbuf && !__last._M_sbuf)
369 {
370 const int_type __ival = traits_type::to_int_type(__val);
371 streambuf_type* __sb = __first._M_sbuf;
372 int_type __c = __sb->sgetc();
373 while (!traits_type::eq_int_type(__c, traits_type::eof())
374 && !traits_type::eq_int_type(__c, __ival))
375 {
376 streamsize __n = __sb->egptr() - __sb->gptr();
377 if (__n > 1)
378 {
379 const _CharT* __p = traits_type::find(__sb->gptr(),
380 __n, __val);
381 if (__p)
382 __n = __p - __sb->gptr();
383 __sb->gbump(__n);
384 __c = __sb->sgetc();
385 }
386 else
387 __c = __sb->snextc();
388 }
389
390 if (!traits_type::eq_int_type(__c, traits_type::eof()))
391 __first._M_c = __c;
392 else
393 __first._M_sbuf = 0;
394 }
395 return __first;
396 }
397
398 _GLIBCXX_END_NAMESPACE
399
400 #endif
401