1 : // Streambuf iterators
2 :
3 : // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
4 : // 2006, 2007, 2009
5 : // Free Software Foundation, Inc.
6 : //
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)
11 : // any later version.
12 :
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.
17 :
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.
21 :
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/>.
26 :
27 : /** @file streambuf_iterator.h
28 : * This is an internal header file, included by other library headers.
29 : * You should not attempt to use it directly.
30 : */
31 :
32 : #ifndef _STREAMBUF_ITERATOR_H
33 : #define _STREAMBUF_ITERATOR_H 1
34 :
35 : #pragma GCC system_header
36 :
37 : #include <streambuf>
38 : #include <debug/debug.h>
39 :
40 : _GLIBCXX_BEGIN_NAMESPACE(std)
41 :
42 : /**
43 : * @addtogroup iterators
44 : * @{
45 : */
46 :
47 : // 24.5.3 Template class istreambuf_iterator
48 : /// Provides input iterator semantics for streambufs.
49 : template<typename _CharT, typename _Traits>
50 : class istreambuf_iterator
51 : : public iterator<input_iterator_tag, _CharT, typename _Traits::off_type,
52 : _CharT*, _CharT&>
53 : {
54 : public:
55 : // Types:
56 : //@{
57 : /// Public typedefs
58 : typedef _CharT char_type;
59 : typedef _Traits traits_type;
60 : typedef typename _Traits::int_type int_type;
61 : typedef basic_streambuf<_CharT, _Traits> streambuf_type;
62 : typedef basic_istream<_CharT, _Traits> istream_type;
63 : //@}
64 :
65 : template<typename _CharT2>
66 : friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
67 : ostreambuf_iterator<_CharT2> >::__type
68 : copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
69 : ostreambuf_iterator<_CharT2>);
70 :
71 : template<bool _IsMove, typename _CharT2>
72 : friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
73 : _CharT2*>::__type
74 : __copy_move_a2(istreambuf_iterator<_CharT2>,
75 : istreambuf_iterator<_CharT2>, _CharT2*);
76 :
77 : template<typename _CharT2>
78 : friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
79 : istreambuf_iterator<_CharT2> >::__type
80 : find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
81 : const _CharT2&);
82 :
83 : private:
84 : // 24.5.3 istreambuf_iterator
85 : // p 1
86 : // If the end of stream is reached (streambuf_type::sgetc()
87 : // returns traits_type::eof()), the iterator becomes equal to
88 : // the "end of stream" iterator value.
89 : // NB: This implementation assumes the "end of stream" value
90 : // is EOF, or -1.
91 : mutable streambuf_type* _M_sbuf;
92 : mutable int_type _M_c;
93 :
94 : public:
95 : /// Construct end of input stream iterator.
96 : istreambuf_iterator() throw()
97 : : _M_sbuf(0), _M_c(traits_type::eof()) { }
98 :
99 : /// Construct start of input stream iterator.
100 0 : istreambuf_iterator(istream_type& __s) throw()
101 0 : : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { }
102 :
103 : /// Construct start of streambuf iterator.
104 0 : istreambuf_iterator(streambuf_type* __s) throw()
105 0 : : _M_sbuf(__s), _M_c(traits_type::eof()) { }
106 :
107 : /// Return the current character pointed to by iterator. This returns
108 : /// streambuf.sgetc(). It cannot be assigned. NB: The result of
109 : /// operator*() on an end of stream is undefined.
110 : char_type
111 : operator*() const
112 : {
113 : #ifdef _GLIBCXX_DEBUG_PEDANTIC
114 : // Dereferencing a past-the-end istreambuf_iterator is a
115 : // libstdc++ extension
116 : __glibcxx_requires_cond(!_M_at_eof(),
117 : _M_message(__gnu_debug::__msg_deref_istreambuf)
118 : ._M_iterator(*this));
119 : #endif
120 : return traits_type::to_char_type(_M_get());
121 : }
122 :
123 : /// Advance the iterator. Calls streambuf.sbumpc().
124 : istreambuf_iterator&
125 : operator++()
126 : {
127 : __glibcxx_requires_cond(!_M_at_eof(),
128 : _M_message(__gnu_debug::__msg_inc_istreambuf)
129 : ._M_iterator(*this));
130 : if (_M_sbuf)
131 : {
132 : _M_sbuf->sbumpc();
133 : _M_c = traits_type::eof();
134 : }
135 : return *this;
136 : }
137 :
138 : /// Advance the iterator. Calls streambuf.sbumpc().
139 : istreambuf_iterator
140 : operator++(int)
141 : {
142 : __glibcxx_requires_cond(!_M_at_eof(),
143 : _M_message(__gnu_debug::__msg_inc_istreambuf)
144 : ._M_iterator(*this));
145 :
146 : istreambuf_iterator __old = *this;
147 : if (_M_sbuf)
148 : {
149 : __old._M_c = _M_sbuf->sbumpc();
150 : _M_c = traits_type::eof();
151 : }
152 : return __old;
153 : }
154 :
155 : // _GLIBCXX_RESOLVE_LIB_DEFECTS
156 : // 110 istreambuf_iterator::equal not const
157 : // NB: there is also number 111 (NAD, Future) pending on this function.
158 : /// Return true both iterators are end or both are not end.
159 : bool
160 : equal(const istreambuf_iterator& __b) const
161 : { return _M_at_eof() == __b._M_at_eof(); }
162 :
163 : private:
164 : int_type
165 : _M_get() const
166 : {
167 : const int_type __eof = traits_type::eof();
168 : int_type __ret = __eof;
169 : if (_M_sbuf)
170 : {
171 : if (!traits_type::eq_int_type(_M_c, __eof))
172 : __ret = _M_c;
173 : else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()),
174 : __eof))
175 : _M_c = __ret;
176 : else
177 : _M_sbuf = 0;
178 : }
179 : return __ret;
180 : }
181 :
182 : bool
183 : _M_at_eof() const
184 : {
185 : const int_type __eof = traits_type::eof();
186 : return traits_type::eq_int_type(_M_get(), __eof);
187 : }
188 : };
189 :
190 : template<typename _CharT, typename _Traits>
191 : inline bool
192 : operator==(const istreambuf_iterator<_CharT, _Traits>& __a,
193 : const istreambuf_iterator<_CharT, _Traits>& __b)
194 : { return __a.equal(__b); }
195 :
196 : template<typename _CharT, typename _Traits>
197 : inline bool
198 : operator!=(const istreambuf_iterator<_CharT, _Traits>& __a,
199 : const istreambuf_iterator<_CharT, _Traits>& __b)
200 : { return !__a.equal(__b); }
201 :
202 : /// Provides output iterator semantics for streambufs.
203 : template<typename _CharT, typename _Traits>
204 : class ostreambuf_iterator
205 : : public iterator<output_iterator_tag, void, void, void, void>
206 : {
207 : public:
208 : // Types:
209 : //@{
210 : /// Public typedefs
211 : typedef _CharT char_type;
212 : typedef _Traits traits_type;
213 : typedef basic_streambuf<_CharT, _Traits> streambuf_type;
214 : typedef basic_ostream<_CharT, _Traits> ostream_type;
215 : //@}
216 :
217 : template<typename _CharT2>
218 : friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value,
219 : ostreambuf_iterator<_CharT2> >::__type
220 : copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>,
221 : ostreambuf_iterator<_CharT2>);
222 :
223 : private:
224 : streambuf_type* _M_sbuf;
225 : bool _M_failed;
226 :
227 : public:
228 : /// Construct output iterator from ostream.
229 0 : ostreambuf_iterator(ostream_type& __s) throw ()
230 0 : : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { }
231 :
232 : /// Construct output iterator from streambuf.
233 : ostreambuf_iterator(streambuf_type* __s) throw ()
234 : : _M_sbuf(__s), _M_failed(!_M_sbuf) { }
235 :
236 : /// Write character to streambuf. Calls streambuf.sputc().
237 : ostreambuf_iterator&
238 : operator=(_CharT __c)
239 : {
240 : if (!_M_failed &&
241 : _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof()))
242 : _M_failed = true;
243 : return *this;
244 : }
245 :
246 : /// Return *this.
247 : ostreambuf_iterator&
248 : operator*()
249 : { return *this; }
250 :
251 : /// Return *this.
252 : ostreambuf_iterator&
253 : operator++(int)
254 : { return *this; }
255 :
256 : /// Return *this.
257 : ostreambuf_iterator&
258 : operator++()
259 : { return *this; }
260 :
261 : /// Return true if previous operator=() failed.
262 : bool
263 0 : failed() const throw()
264 0 : { return _M_failed; }
265 :
266 : ostreambuf_iterator&
267 : _M_put(const _CharT* __ws, streamsize __len)
268 : {
269 : if (__builtin_expect(!_M_failed, true)
270 : && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len,
271 : false))
272 : _M_failed = true;
273 : return *this;
274 : }
275 : };
276 :
277 : // Overloads for streambuf iterators.
278 : template<typename _CharT>
279 : typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
280 : ostreambuf_iterator<_CharT> >::__type
281 : copy(istreambuf_iterator<_CharT> __first,
282 : istreambuf_iterator<_CharT> __last,
283 : ostreambuf_iterator<_CharT> __result)
284 : {
285 : if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed)
286 : {
287 : bool __ineof;
288 : __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof);
289 : if (!__ineof)
290 : __result._M_failed = true;
291 : }
292 : return __result;
293 : }
294 :
295 : template<bool _IsMove, typename _CharT>
296 : typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
297 : ostreambuf_iterator<_CharT> >::__type
298 : __copy_move_a2(_CharT* __first, _CharT* __last,
299 : ostreambuf_iterator<_CharT> __result)
300 : {
301 : const streamsize __num = __last - __first;
302 : if (__num > 0)
303 : __result._M_put(__first, __num);
304 : return __result;
305 : }
306 :
307 : template<bool _IsMove, typename _CharT>
308 : typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
309 : ostreambuf_iterator<_CharT> >::__type
310 : __copy_move_a2(const _CharT* __first, const _CharT* __last,
311 : ostreambuf_iterator<_CharT> __result)
312 : {
313 : const streamsize __num = __last - __first;
314 : if (__num > 0)
315 : __result._M_put(__first, __num);
316 : return __result;
317 : }
318 :
319 : template<bool _IsMove, typename _CharT>
320 : typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
321 : _CharT*>::__type
322 : __copy_move_a2(istreambuf_iterator<_CharT> __first,
323 : istreambuf_iterator<_CharT> __last, _CharT* __result)
324 : {
325 : typedef istreambuf_iterator<_CharT> __is_iterator_type;
326 : typedef typename __is_iterator_type::traits_type traits_type;
327 : typedef typename __is_iterator_type::streambuf_type streambuf_type;
328 : typedef typename traits_type::int_type int_type;
329 :
330 : if (__first._M_sbuf && !__last._M_sbuf)
331 : {
332 : streambuf_type* __sb = __first._M_sbuf;
333 : int_type __c = __sb->sgetc();
334 : while (!traits_type::eq_int_type(__c, traits_type::eof()))
335 : {
336 : const streamsize __n = __sb->egptr() - __sb->gptr();
337 : if (__n > 1)
338 : {
339 : traits_type::copy(__result, __sb->gptr(), __n);
340 : __sb->gbump(__n);
341 : __result += __n;
342 : __c = __sb->underflow();
343 : }
344 : else
345 : {
346 : *__result++ = traits_type::to_char_type(__c);
347 : __c = __sb->snextc();
348 : }
349 : }
350 : }
351 : return __result;
352 : }
353 :
354 : template<typename _CharT>
355 : typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value,
356 : istreambuf_iterator<_CharT> >::__type
357 : find(istreambuf_iterator<_CharT> __first,
358 : istreambuf_iterator<_CharT> __last, const _CharT& __val)
359 : {
360 : typedef istreambuf_iterator<_CharT> __is_iterator_type;
361 : typedef typename __is_iterator_type::traits_type traits_type;
362 : typedef typename __is_iterator_type::streambuf_type streambuf_type;
363 : typedef typename traits_type::int_type int_type;
364 :
365 : if (__first._M_sbuf && !__last._M_sbuf)
366 : {
367 : const int_type __ival = traits_type::to_int_type(__val);
368 : streambuf_type* __sb = __first._M_sbuf;
369 : int_type __c = __sb->sgetc();
370 : while (!traits_type::eq_int_type(__c, traits_type::eof())
371 : && !traits_type::eq_int_type(__c, __ival))
372 : {
373 : streamsize __n = __sb->egptr() - __sb->gptr();
374 : if (__n > 1)
375 : {
376 : const _CharT* __p = traits_type::find(__sb->gptr(),
377 : __n, __val);
378 : if (__p)
379 : __n = __p - __sb->gptr();
380 : __sb->gbump(__n);
381 : __c = __sb->sgetc();
382 : }
383 : else
384 : __c = __sb->snextc();
385 : }
386 :
387 : if (!traits_type::eq_int_type(__c, traits_type::eof()))
388 : __first._M_c = __c;
389 : else
390 : __first._M_sbuf = 0;
391 : }
392 : return __first;
393 : }
394 :
395 : // @} group iterators
396 :
397 : _GLIBCXX_END_NAMESPACE
398 :
399 : #endif
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