No empty .Rs/.Re
[netbsd-mini2440.git] / gnu / dist / gcc4 / libstdc++-v3 / include / std / std_ostream.h
blobffc1a2817304dee2a47f3a3725451623218598c2
1 // Output streams -*- C++ -*-
3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
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.
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.
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.
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.
32 // ISO C++ 14882: 27.6.2 Output streams
35 /** @file ostream
36 * This is a Standard C++ Library header.
39 #ifndef _GLIBCXX_OSTREAM
40 #define _GLIBCXX_OSTREAM 1
42 #pragma GCC system_header
44 #include <ios>
46 namespace std
48 // [27.6.2.1] Template class basic_ostream
49 /**
50 * @brief Controlling output.
52 * This is the base class for all output streams. It provides text
53 * formatting of all builtin types, and communicates with any class
54 * derived from basic_streambuf to do the actual output.
56 template<typename _CharT, typename _Traits>
57 class basic_ostream : virtual public basic_ios<_CharT, _Traits>
59 public:
60 // Types (inherited from basic_ios (27.4.4)):
61 typedef _CharT char_type;
62 typedef typename _Traits::int_type int_type;
63 typedef typename _Traits::pos_type pos_type;
64 typedef typename _Traits::off_type off_type;
65 typedef _Traits traits_type;
67 // Non-standard Types:
68 typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
69 typedef basic_ios<_CharT, _Traits> __ios_type;
70 typedef basic_ostream<_CharT, _Traits> __ostream_type;
71 typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> >
72 __num_put_type;
73 typedef ctype<_CharT> __ctype_type;
75 template<typename _CharT2, typename _Traits2>
76 friend basic_ostream<_CharT2, _Traits2>&
77 operator<<(basic_ostream<_CharT2, _Traits2>&, _CharT2);
79 template<typename _Traits2>
80 friend basic_ostream<char, _Traits2>&
81 operator<<(basic_ostream<char, _Traits2>&, char);
83 template<typename _CharT2, typename _Traits2>
84 friend basic_ostream<_CharT2, _Traits2>&
85 operator<<(basic_ostream<_CharT2, _Traits2>&, const _CharT2*);
87 template<typename _Traits2>
88 friend basic_ostream<char, _Traits2>&
89 operator<<(basic_ostream<char, _Traits2>&, const char*);
91 template<typename _CharT2, typename _Traits2>
92 friend basic_ostream<_CharT2, _Traits2>&
93 operator<<(basic_ostream<_CharT2, _Traits2>&, const char*);
95 // [27.6.2.2] constructor/destructor
96 /**
97 * @brief Base constructor.
99 * This ctor is almost never called by the user directly, rather from
100 * derived classes' initialization lists, which pass a pointer to
101 * their own stream buffer.
103 explicit
104 basic_ostream(__streambuf_type* __sb)
105 { this->init(__sb); }
108 * @brief Base destructor.
110 * This does very little apart from providing a virtual base dtor.
112 virtual
113 ~basic_ostream() { }
115 // [27.6.2.3] prefix/suffix
116 class sentry;
117 friend class sentry;
119 // [27.6.2.5] formatted output
120 // [27.6.2.5.3] basic_ostream::operator<<
121 //@{
123 * @brief Interface for manipulators.
125 * Manuipulators such as @c std::endl and @c std::hex use these
126 * functions in constructs like "std::cout << std::endl". For more
127 * information, see the iomanip header.
129 inline __ostream_type&
130 operator<<(__ostream_type& (*__pf)(__ostream_type&));
132 inline __ostream_type&
133 operator<<(__ios_type& (*__pf)(__ios_type&));
135 inline __ostream_type&
136 operator<<(ios_base& (*__pf) (ios_base&));
137 //@}
139 // [27.6.2.5.2] arithmetic inserters
141 * @name Arithmetic Inserters
143 * All the @c operator<< functions (aka <em>formatted output
144 * functions</em>) have some common behavior. Each starts by
145 * constructing a temporary object of type std::basic_ostream::sentry.
146 * This can have several effects, concluding with the setting of a
147 * status flag; see the sentry documentation for more.
149 * If the sentry status is good, the function tries to generate
150 * whatever data is appropriate for the type of the argument.
152 * If an exception is thrown during insertion, ios_base::badbit
153 * will be turned on in the stream's error state without causing an
154 * ios_base::failure to be thrown. The original exception will then
155 * be rethrown.
157 //@{
159 * @brief Basic arithmetic inserters
160 * @param A variable of builtin type.
161 * @return @c *this if successful
163 * These functions use the stream's current locale (specifically, the
164 * @c num_get facet) to perform numeric formatting.
166 __ostream_type&
167 operator<<(long __n);
169 __ostream_type&
170 operator<<(unsigned long __n);
172 __ostream_type&
173 operator<<(bool __n);
175 __ostream_type&
176 operator<<(short __n);
178 __ostream_type&
179 operator<<(unsigned short __n);
181 __ostream_type&
182 operator<<(int __n);
184 __ostream_type&
185 operator<<(unsigned int __n);
187 #ifdef _GLIBCXX_USE_LONG_LONG
188 __ostream_type&
189 operator<<(long long __n);
191 __ostream_type&
192 operator<<(unsigned long long __n);
193 #endif
195 __ostream_type&
196 operator<<(double __f);
198 __ostream_type&
199 operator<<(float __f);
201 __ostream_type&
202 operator<<(long double __f);
204 __ostream_type&
205 operator<<(const void* __p);
208 * @brief Extracting from another streambuf.
209 * @param sb A pointer to a streambuf
211 * This function behaves like one of the basic arithmetic extractors,
212 * in that it also constructs a sentry object and has the same error
213 * handling behavior.
215 * If @a sb is NULL, the stream will set failbit in its error state.
217 * Characters are extracted from @a sb and inserted into @c *this
218 * until one of the following occurs:
220 * - the input stream reaches end-of-file,
221 * - insertion into the output sequence fails (in this case, the
222 * character that would have been inserted is not extracted), or
223 * - an exception occurs while getting a character from @a sb, which
224 * sets failbit in the error state
226 * If the function inserts no characters, failbit is set.
228 __ostream_type&
229 operator<<(__streambuf_type* __sb);
230 //@}
232 // [27.6.2.6] unformatted output functions
234 * @name Unformatted Output Functions
236 * All the unformatted output functions have some common behavior.
237 * Each starts by constructing a temporary object of type
238 * std::basic_ostream::sentry. This has several effects, concluding
239 * with the setting of a status flag; see the sentry documentation
240 * for more.
242 * If the sentry status is good, the function tries to generate
243 * whatever data is appropriate for the type of the argument.
245 * If an exception is thrown during insertion, ios_base::badbit
246 * will be turned on in the stream's error state. If badbit is on in
247 * the stream's exceptions mask, the exception will be rethrown
248 * without completing its actions.
250 //@{
252 * @brief Simple insertion.
253 * @param c The character to insert.
254 * @return *this
256 * Tries to insert @a c.
258 * @note This function is not overloaded on signed char and
259 * unsigned char.
261 __ostream_type&
262 put(char_type __c);
264 // Core write functionality, without sentry.
265 void
266 _M_write(const char_type* __s, streamsize __n)
268 streamsize __put = this->rdbuf()->sputn(__s, __n);
269 if (__put != __n)
270 this->setstate(ios_base::badbit);
274 * @brief Character string insertion.
275 * @param s The array to insert.
276 * @param n Maximum number of characters to insert.
277 * @return *this
279 * Characters are copied from @a s and inserted into the stream until
280 * one of the following happens:
282 * - @a n characters are inserted
283 * - inserting into the output sequence fails (in this case, badbit
284 * will be set in the stream's error state)
286 * @note This function is not overloaded on signed char and
287 * unsigned char.
289 __ostream_type&
290 write(const char_type* __s, streamsize __n);
291 //@}
294 * @brief Synchronizing the stream buffer.
295 * @return *this
297 * If @c rdbuf() is a null pointer, changes nothing.
299 * Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1,
300 * sets badbit.
302 __ostream_type&
303 flush();
305 // [27.6.2.4] seek members
307 * @brief Getting the current write position.
308 * @return A file position object.
310 * If @c fail() is not false, returns @c pos_type(-1) to indicate
311 * failure. Otherwise returns @c rdbuf()->pubseekoff(0,cur,out).
313 pos_type
314 tellp();
317 * @brief Changing the current write position.
318 * @param pos A file position object.
319 * @return *this
321 * If @c fail() is not true, calls @c rdbuf()->pubseekpos(pos). If
322 * that function fails, sets failbit.
324 __ostream_type&
325 seekp(pos_type);
328 * @brief Changing the current write position.
329 * @param off A file offset object.
330 * @param dir The direction in which to seek.
331 * @return *this
333 * If @c fail() is not true, calls @c rdbuf()->pubseekoff(off,dir).
334 * If that function fails, sets failbit.
336 __ostream_type&
337 seekp(off_type, ios_base::seekdir);
339 protected:
340 explicit
341 basic_ostream() { }
345 * @brief Performs setup work for output streams.
347 * Objects of this class are created before all of the standard
348 * inserters are run. It is responsible for "exception-safe prefix and
349 * suffix operations." Additional actions may be added by the
350 * implementation, and we list them in
351 * http://gcc.gnu.org/onlinedocs/libstdc++/17_intro/howto.html#5
352 * under [27.6] notes.
354 template <typename _CharT, typename _Traits>
355 class basic_ostream<_CharT, _Traits>::sentry
357 // Data Members:
358 bool _M_ok;
359 basic_ostream<_CharT,_Traits>& _M_os;
361 public:
363 * @brief The constructor performs preparatory work.
364 * @param os The output stream to guard.
366 * If the stream state is good (@a os.good() is true), then if the
367 * stream is tied to another output stream, @c is.tie()->flush()
368 * is called to synchronize the output sequences.
370 * If the stream state is still good, then the sentry state becomes
371 * true ("okay").
373 explicit
374 sentry(basic_ostream<_CharT,_Traits>& __os);
377 * @brief Possibly flushes the stream.
379 * If @c ios_base::unitbuf is set in @c os.flags(), and
380 * @c std::uncaught_exception() is true, the sentry destructor calls
381 * @c flush() on the output stream.
383 ~sentry()
385 // XXX MT
386 if (_M_os.flags() & ios_base::unitbuf && !uncaught_exception())
388 // Can't call flush directly or else will get into recursive lock.
389 if (_M_os.rdbuf() && _M_os.rdbuf()->pubsync() == -1)
390 _M_os.setstate(ios_base::badbit);
395 * @brief Quick status checking.
396 * @return The sentry state.
398 * For ease of use, sentries may be converted to booleans. The
399 * return value is that of the sentry state (true == okay).
401 operator bool() const
402 { return _M_ok; }
405 // [27.6.2.5.4] character insertion templates
406 //@{
408 * @brief Character inserters
409 * @param out An output stream.
410 * @param c A character.
411 * @return out
413 * Behaves like one of the formatted arithmetic inserters described in
414 * std::basic_ostream. After constructing a sentry object with good
415 * status, this function inserts a single character and any required
416 * padding (as determined by [22.2.2.2.2]). @c out.width(0) is then
417 * called.
419 * If @a c is of type @c char and the character type of the stream is not
420 * @c char, the character is widened before insertion.
422 template<typename _CharT, typename _Traits>
423 basic_ostream<_CharT, _Traits>&
424 operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c);
426 template<typename _CharT, typename _Traits>
427 basic_ostream<_CharT, _Traits>&
428 operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
429 { return (__out << __out.widen(__c)); }
431 // Specialization
432 template <class _Traits>
433 basic_ostream<char, _Traits>&
434 operator<<(basic_ostream<char, _Traits>& __out, char __c);
436 // Signed and unsigned
437 template<class _Traits>
438 basic_ostream<char, _Traits>&
439 operator<<(basic_ostream<char, _Traits>& __out, signed char __c)
440 { return (__out << static_cast<char>(__c)); }
442 template<class _Traits>
443 basic_ostream<char, _Traits>&
444 operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)
445 { return (__out << static_cast<char>(__c)); }
446 //@}
448 //@{
450 * @brief String inserters
451 * @param out An output stream.
452 * @param s A character string.
453 * @return out
454 * @pre @a s must be a non-NULL pointer
456 * Behaves like one of the formatted arithmetic inserters described in
457 * std::basic_ostream. After constructing a sentry object with good
458 * status, this function inserts @c traits::length(s) characters starting
459 * at @a s, widened if necessary, followed by any required padding (as
460 * determined by [22.2.2.2.2]). @c out.width(0) is then called.
462 template<typename _CharT, typename _Traits>
463 basic_ostream<_CharT, _Traits>&
464 operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s);
466 template<typename _CharT, typename _Traits>
467 basic_ostream<_CharT, _Traits> &
468 operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s);
470 // Partial specializationss
471 template<class _Traits>
472 basic_ostream<char, _Traits>&
473 operator<<(basic_ostream<char, _Traits>& __out, const char* __s);
475 // Signed and unsigned
476 template<class _Traits>
477 basic_ostream<char, _Traits>&
478 operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)
479 { return (__out << reinterpret_cast<const char*>(__s)); }
481 template<class _Traits>
482 basic_ostream<char, _Traits> &
483 operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)
484 { return (__out << reinterpret_cast<const char*>(__s)); }
485 //@}
487 // [27.6.2.7] standard basic_ostream manipulators
489 * @brief Write a newline and flush the stream.
491 * This manipulator is often mistakenly used when a simple newline is
492 * desired, leading to poor buffering performance. See
493 * http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#2 for more
494 * on this subject.
496 template<typename _CharT, typename _Traits>
497 basic_ostream<_CharT, _Traits>&
498 endl(basic_ostream<_CharT, _Traits>& __os)
499 { return flush(__os.put(__os.widen('\n'))); }
502 * @brief Write a null character into the output sequence.
504 * "Null character" is @c CharT() by definition. For CharT of @c char,
505 * this correctly writes the ASCII @c NUL character string terminator.
507 template<typename _CharT, typename _Traits>
508 basic_ostream<_CharT, _Traits>&
509 ends(basic_ostream<_CharT, _Traits>& __os)
510 { return __os.put(_CharT()); }
513 * @brief Flushes the output stream.
515 * This manipulator simply calls the stream's @c flush() member function.
517 template<typename _CharT, typename _Traits>
518 basic_ostream<_CharT, _Traits>&
519 flush(basic_ostream<_CharT, _Traits>& __os)
520 { return __os.flush(); }
522 } // namespace std
524 #ifndef _GLIBCXX_EXPORT_TEMPLATE
525 # include <bits/ostream.tcc>
526 #endif
528 #endif /* _GLIBCXX_OSTREAM */