1 | // Streambuf iterators |
2 | |
3 | // Copyright (C) 1997-2017 Free Software Foundation, Inc. |
4 | // |
5 | // This file is part of the GNU ISO C++ Library. This library is free |
6 | // software; you can redistribute it and/or modify it under the |
7 | // terms of the GNU General Public License as published by the |
8 | // Free Software Foundation; either version 3, or (at your option) |
9 | // any later version. |
10 | |
11 | // This library is distributed in the hope that it will be useful, |
12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | // GNU General Public License for more details. |
15 | |
16 | // Under Section 7 of GPL version 3, you are granted additional |
17 | // permissions described in the GCC Runtime Library Exception, version |
18 | // 3.1, as published by the Free Software Foundation. |
19 | |
20 | // You should have received a copy of the GNU General Public License and |
21 | // a copy of the GCC Runtime Library Exception along with this program; |
22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
23 | // <http://www.gnu.org/licenses/>. |
24 | |
25 | /** @file bits/streambuf_iterator.h |
26 | * This is an internal header file, included by other library headers. |
27 | * Do not attempt to use it directly. @headername{iterator} |
28 | */ |
29 | |
30 | #ifndef _STREAMBUF_ITERATOR_H |
31 | #define _STREAMBUF_ITERATOR_H 1 |
32 | |
33 | #pragma GCC system_header |
34 | |
35 | #include <streambuf> |
36 | #include <debug/debug.h> |
37 | |
38 | namespace std _GLIBCXX_VISIBILITY(default) |
39 | { |
40 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
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*, |
53 | #if __cplusplus >= 201103L |
54 | // LWG 445. |
55 | _CharT> |
56 | #else |
57 | _CharT&> |
58 | #endif |
59 | { |
60 | public: |
61 | // Types: |
62 | //@{ |
63 | /// Public typedefs |
64 | typedef _CharT char_type; |
65 | typedef _Traits traits_type; |
66 | typedef typename _Traits::int_type int_type; |
67 | typedef basic_streambuf<_CharT, _Traits> streambuf_type; |
68 | typedef basic_istream<_CharT, _Traits> istream_type; |
69 | //@} |
70 | |
71 | template<typename _CharT2> |
72 | friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, |
73 | ostreambuf_iterator<_CharT2> >::__type |
74 | copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, |
75 | ostreambuf_iterator<_CharT2>); |
76 | |
77 | template<bool _IsMove, typename _CharT2> |
78 | friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, |
79 | _CharT2*>::__type |
80 | __copy_move_a2(istreambuf_iterator<_CharT2>, |
81 | istreambuf_iterator<_CharT2>, _CharT2*); |
82 | |
83 | template<typename _CharT2> |
84 | friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, |
85 | istreambuf_iterator<_CharT2> >::__type |
86 | find(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, |
87 | const _CharT2&); |
88 | |
89 | private: |
90 | // 24.5.3 istreambuf_iterator |
91 | // p 1 |
92 | // If the end of stream is reached (streambuf_type::sgetc() |
93 | // returns traits_type::eof()), the iterator becomes equal to |
94 | // the "end of stream" iterator value. |
95 | // NB: This implementation assumes the "end of stream" value |
96 | // is EOF, or -1. |
97 | mutable streambuf_type* _M_sbuf; |
98 | mutable int_type _M_c; |
99 | |
100 | public: |
101 | /// Construct end of input stream iterator. |
102 | _GLIBCXX_CONSTEXPR istreambuf_iterator() _GLIBCXX_USE_NOEXCEPT |
103 | : _M_sbuf(0), _M_c(traits_type::eof()) { } |
104 | |
105 | #if __cplusplus >= 201103L |
106 | istreambuf_iterator(const istreambuf_iterator&) noexcept = default; |
107 | |
108 | ~istreambuf_iterator() = default; |
109 | #endif |
110 | |
111 | /// Construct start of input stream iterator. |
112 | istreambuf_iterator(istream_type& __s) _GLIBCXX_USE_NOEXCEPT |
113 | : _M_sbuf(__s.rdbuf()), _M_c(traits_type::eof()) { } |
114 | |
115 | /// Construct start of streambuf iterator. |
116 | istreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT |
117 | : _M_sbuf(__s), _M_c(traits_type::eof()) { } |
118 | |
119 | /// Return the current character pointed to by iterator. This returns |
120 | /// streambuf.sgetc(). It cannot be assigned. NB: The result of |
121 | /// operator*() on an end of stream is undefined. |
122 | char_type |
123 | operator*() const |
124 | { |
125 | #ifdef _GLIBCXX_DEBUG_PEDANTIC |
126 | // Dereferencing a past-the-end istreambuf_iterator is a |
127 | // libstdc++ extension |
128 | __glibcxx_requires_cond(!_M_at_eof(), |
129 | _M_message(__gnu_debug::__msg_deref_istreambuf) |
130 | ._M_iterator(*this)); |
131 | #endif |
132 | return traits_type::to_char_type(_M_get()); |
133 | } |
134 | |
135 | /// Advance the iterator. Calls streambuf.sbumpc(). |
136 | istreambuf_iterator& |
137 | operator++() |
138 | { |
139 | __glibcxx_requires_cond(!_M_at_eof(), |
140 | _M_message(__gnu_debug::__msg_inc_istreambuf) |
141 | ._M_iterator(*this)); |
142 | if (_M_sbuf) |
143 | { |
144 | _M_sbuf->sbumpc(); |
145 | _M_c = traits_type::eof(); |
146 | } |
147 | return *this; |
148 | } |
149 | |
150 | /// Advance the iterator. Calls streambuf.sbumpc(). |
151 | istreambuf_iterator |
152 | operator++(int) |
153 | { |
154 | __glibcxx_requires_cond(!_M_at_eof(), |
155 | _M_message(__gnu_debug::__msg_inc_istreambuf) |
156 | ._M_iterator(*this)); |
157 | |
158 | istreambuf_iterator __old = *this; |
159 | if (_M_sbuf) |
160 | { |
161 | __old._M_c = _M_sbuf->sbumpc(); |
162 | _M_c = traits_type::eof(); |
163 | } |
164 | return __old; |
165 | } |
166 | |
167 | // _GLIBCXX_RESOLVE_LIB_DEFECTS |
168 | // 110 istreambuf_iterator::equal not const |
169 | // NB: there is also number 111 (NAD, Future) pending on this function. |
170 | /// Return true both iterators are end or both are not end. |
171 | bool |
172 | equal(const istreambuf_iterator& __b) const |
173 | { return _M_at_eof() == __b._M_at_eof(); } |
174 | |
175 | private: |
176 | int_type |
177 | _M_get() const |
178 | { |
179 | const int_type __eof = traits_type::eof(); |
180 | int_type __ret = __eof; |
181 | if (_M_sbuf) |
182 | { |
183 | if (!traits_type::eq_int_type(_M_c, __eof)) |
184 | __ret = _M_c; |
185 | else if (!traits_type::eq_int_type((__ret = _M_sbuf->sgetc()), |
186 | __eof)) |
187 | _M_c = __ret; |
188 | else |
189 | _M_sbuf = 0; |
190 | } |
191 | return __ret; |
192 | } |
193 | |
194 | bool |
195 | _M_at_eof() const |
196 | { |
197 | const int_type __eof = traits_type::eof(); |
198 | return traits_type::eq_int_type(_M_get(), __eof); |
199 | } |
200 | }; |
201 | |
202 | template<typename _CharT, typename _Traits> |
203 | inline bool |
204 | operator==(const istreambuf_iterator<_CharT, _Traits>& __a, |
205 | const istreambuf_iterator<_CharT, _Traits>& __b) |
206 | { return __a.equal(__b); } |
207 | |
208 | template<typename _CharT, typename _Traits> |
209 | inline bool |
210 | operator!=(const istreambuf_iterator<_CharT, _Traits>& __a, |
211 | const istreambuf_iterator<_CharT, _Traits>& __b) |
212 | { return !__a.equal(__b); } |
213 | |
214 | /// Provides output iterator semantics for streambufs. |
215 | template<typename _CharT, typename _Traits> |
216 | class ostreambuf_iterator |
217 | : public iterator<output_iterator_tag, void, void, void, void> |
218 | { |
219 | public: |
220 | // Types: |
221 | //@{ |
222 | /// Public typedefs |
223 | typedef _CharT char_type; |
224 | typedef _Traits traits_type; |
225 | typedef basic_streambuf<_CharT, _Traits> streambuf_type; |
226 | typedef basic_ostream<_CharT, _Traits> ostream_type; |
227 | //@} |
228 | |
229 | template<typename _CharT2> |
230 | friend typename __gnu_cxx::__enable_if<__is_char<_CharT2>::__value, |
231 | ostreambuf_iterator<_CharT2> >::__type |
232 | copy(istreambuf_iterator<_CharT2>, istreambuf_iterator<_CharT2>, |
233 | ostreambuf_iterator<_CharT2>); |
234 | |
235 | private: |
236 | streambuf_type* _M_sbuf; |
237 | bool _M_failed; |
238 | |
239 | public: |
240 | /// Construct output iterator from ostream. |
241 | ostreambuf_iterator(ostream_type& __s) _GLIBCXX_USE_NOEXCEPT |
242 | : _M_sbuf(__s.rdbuf()), _M_failed(!_M_sbuf) { } |
243 | |
244 | /// Construct output iterator from streambuf. |
245 | ostreambuf_iterator(streambuf_type* __s) _GLIBCXX_USE_NOEXCEPT |
246 | : _M_sbuf(__s), _M_failed(!_M_sbuf) { } |
247 | |
248 | /// Write character to streambuf. Calls streambuf.sputc(). |
249 | ostreambuf_iterator& |
250 | operator=(_CharT __c) |
251 | { |
252 | if (!_M_failed && |
253 | _Traits::eq_int_type(_M_sbuf->sputc(__c), _Traits::eof())) |
254 | _M_failed = true; |
255 | return *this; |
256 | } |
257 | |
258 | /// Return *this. |
259 | ostreambuf_iterator& |
260 | operator*() |
261 | { return *this; } |
262 | |
263 | /// Return *this. |
264 | ostreambuf_iterator& |
265 | operator++(int) |
266 | { return *this; } |
267 | |
268 | /// Return *this. |
269 | ostreambuf_iterator& |
270 | operator++() |
271 | { return *this; } |
272 | |
273 | /// Return true if previous operator=() failed. |
274 | bool |
275 | failed() const _GLIBCXX_USE_NOEXCEPT |
276 | { return _M_failed; } |
277 | |
278 | ostreambuf_iterator& |
279 | _M_put(const _CharT* __ws, streamsize __len) |
280 | { |
281 | if (__builtin_expect(!_M_failed, true) |
282 | && __builtin_expect(this->_M_sbuf->sputn(__ws, __len) != __len, |
283 | false)) |
284 | _M_failed = true; |
285 | return *this; |
286 | } |
287 | }; |
288 | |
289 | // Overloads for streambuf iterators. |
290 | template<typename _CharT> |
291 | typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, |
292 | ostreambuf_iterator<_CharT> >::__type |
293 | copy(istreambuf_iterator<_CharT> __first, |
294 | istreambuf_iterator<_CharT> __last, |
295 | ostreambuf_iterator<_CharT> __result) |
296 | { |
297 | if (__first._M_sbuf && !__last._M_sbuf && !__result._M_failed) |
298 | { |
299 | bool __ineof; |
300 | __copy_streambufs_eof(__first._M_sbuf, __result._M_sbuf, __ineof); |
301 | if (!__ineof) |
302 | __result._M_failed = true; |
303 | } |
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(_CharT* __first, _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 | ostreambuf_iterator<_CharT> >::__type |
322 | __copy_move_a2(const _CharT* __first, const _CharT* __last, |
323 | ostreambuf_iterator<_CharT> __result) |
324 | { |
325 | const streamsize __num = __last - __first; |
326 | if (__num > 0) |
327 | __result._M_put(__first, __num); |
328 | return __result; |
329 | } |
330 | |
331 | template<bool _IsMove, typename _CharT> |
332 | typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, |
333 | _CharT*>::__type |
334 | __copy_move_a2(istreambuf_iterator<_CharT> __first, |
335 | istreambuf_iterator<_CharT> __last, _CharT* __result) |
336 | { |
337 | typedef istreambuf_iterator<_CharT> __is_iterator_type; |
338 | typedef typename __is_iterator_type::traits_type traits_type; |
339 | typedef typename __is_iterator_type::streambuf_type streambuf_type; |
340 | typedef typename traits_type::int_type int_type; |
341 | |
342 | if (__first._M_sbuf && !__last._M_sbuf) |
343 | { |
344 | streambuf_type* __sb = __first._M_sbuf; |
345 | int_type __c = __sb->sgetc(); |
346 | while (!traits_type::eq_int_type(__c, traits_type::eof())) |
347 | { |
348 | const streamsize __n = __sb->egptr() - __sb->gptr(); |
349 | if (__n > 1) |
350 | { |
351 | traits_type::copy(__result, __sb->gptr(), __n); |
352 | __sb->__safe_gbump(__n); |
353 | __result += __n; |
354 | __c = __sb->underflow(); |
355 | } |
356 | else |
357 | { |
358 | *__result++ = traits_type::to_char_type(__c); |
359 | __c = __sb->snextc(); |
360 | } |
361 | } |
362 | } |
363 | return __result; |
364 | } |
365 | |
366 | template<typename _CharT> |
367 | typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, |
368 | istreambuf_iterator<_CharT> >::__type |
369 | find(istreambuf_iterator<_CharT> __first, |
370 | istreambuf_iterator<_CharT> __last, const _CharT& __val) |
371 | { |
372 | typedef istreambuf_iterator<_CharT> __is_iterator_type; |
373 | typedef typename __is_iterator_type::traits_type traits_type; |
374 | typedef typename __is_iterator_type::streambuf_type streambuf_type; |
375 | typedef typename traits_type::int_type int_type; |
376 | |
377 | if (__first._M_sbuf && !__last._M_sbuf) |
378 | { |
379 | const int_type __ival = traits_type::to_int_type(__val); |
380 | streambuf_type* __sb = __first._M_sbuf; |
381 | int_type __c = __sb->sgetc(); |
382 | while (!traits_type::eq_int_type(__c, traits_type::eof()) |
383 | && !traits_type::eq_int_type(__c, __ival)) |
384 | { |
385 | streamsize __n = __sb->egptr() - __sb->gptr(); |
386 | if (__n > 1) |
387 | { |
388 | const _CharT* __p = traits_type::find(__sb->gptr(), |
389 | __n, __val); |
390 | if (__p) |
391 | __n = __p - __sb->gptr(); |
392 | __sb->__safe_gbump(__n); |
393 | __c = __sb->sgetc(); |
394 | } |
395 | else |
396 | __c = __sb->snextc(); |
397 | } |
398 | |
399 | if (!traits_type::eq_int_type(__c, traits_type::eof())) |
400 | __first._M_c = __c; |
401 | else |
402 | __first._M_sbuf = 0; |
403 | } |
404 | return __first; |
405 | } |
406 | |
407 | // @} group iterators |
408 | |
409 | _GLIBCXX_END_NAMESPACE_VERSION |
410 | } // namespace |
411 | |
412 | #endif |
413 | |