File Coverage

/usr/include/c++/5/ostream
Criterion Covered Total %
statement 0 4 0.0
branch 0 24 0.0
condition n/a
subroutine n/a
pod n/a
total 0 28 0.0


line stmt bran cond sub pod time code
1             // Output streams -*- C++ -*-
2              
3             // Copyright (C) 1997-2015 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             // .
24              
25             /** @file include/ostream
26             * This is a Standard C++ Library header.
27             */
28              
29             //
30             // ISO C++ 14882: 27.6.2 Output streams
31             //
32              
33             #ifndef _GLIBCXX_OSTREAM
34             #define _GLIBCXX_OSTREAM 1
35              
36             #pragma GCC system_header
37              
38             #include
39             #include
40              
41             namespace std _GLIBCXX_VISIBILITY(default)
42             {
43             _GLIBCXX_BEGIN_NAMESPACE_VERSION
44              
45             /**
46             * @brief Template class basic_ostream.
47             * @ingroup io
48             *
49             * @tparam _CharT Type of character stream.
50             * @tparam _Traits Traits for character type, defaults to
51             * char_traits<_CharT>.
52             *
53             * This is the base class for all output streams. It provides text
54             * formatting of all builtin types, and communicates with any class
55             * derived from basic_streambuf to do the actual output.
56             */
57             template
58             class basic_ostream : virtual public basic_ios<_CharT, _Traits>
59             {
60             public:
61             // Types (inherited from basic_ios):
62             typedef _CharT char_type;
63             typedef typename _Traits::int_type int_type;
64             typedef typename _Traits::pos_type pos_type;
65             typedef typename _Traits::off_type off_type;
66             typedef _Traits traits_type;
67              
68             // Non-standard Types:
69             typedef basic_streambuf<_CharT, _Traits> __streambuf_type;
70             typedef basic_ios<_CharT, _Traits> __ios_type;
71             typedef basic_ostream<_CharT, _Traits> __ostream_type;
72             typedef num_put<_CharT, ostreambuf_iterator<_CharT, _Traits> >
73             __num_put_type;
74             typedef ctype<_CharT> __ctype_type;
75              
76             /**
77             * @brief Base constructor.
78             *
79             * This ctor is almost never called by the user directly, rather from
80             * derived classes' initialization lists, which pass a pointer to
81             * their own stream buffer.
82             */
83             explicit
84             basic_ostream(__streambuf_type* __sb)
85             { this->init(__sb); }
86              
87             /**
88             * @brief Base destructor.
89             *
90             * This does very little apart from providing a virtual base dtor.
91             */
92             virtual
93             ~basic_ostream() { }
94              
95             /// Safe prefix/suffix operations.
96             class sentry;
97             friend class sentry;
98              
99             //@{
100             /**
101             * @brief Interface for manipulators.
102             *
103             * Manipulators such as @c std::endl and @c std::hex use these
104             * functions in constructs like "std::cout << std::endl". For more
105             * information, see the iomanip header.
106             */
107             __ostream_type&
108             operator<<(__ostream_type& (*__pf)(__ostream_type&))
109             {
110             // _GLIBCXX_RESOLVE_LIB_DEFECTS
111             // DR 60. What is a formatted input function?
112             // The inserters for manipulators are *not* formatted output functions.
113 0           return __pf(*this);
114             }
115              
116             __ostream_type&
117             operator<<(__ios_type& (*__pf)(__ios_type&))
118             {
119             // _GLIBCXX_RESOLVE_LIB_DEFECTS
120             // DR 60. What is a formatted input function?
121             // The inserters for manipulators are *not* formatted output functions.
122             __pf(*this);
123             return *this;
124             }
125              
126             __ostream_type&
127             operator<<(ios_base& (*__pf) (ios_base&))
128             {
129             // _GLIBCXX_RESOLVE_LIB_DEFECTS
130             // DR 60. What is a formatted input function?
131             // The inserters for manipulators are *not* formatted output functions.
132             __pf(*this);
133             return *this;
134             }
135             //@}
136              
137             //@{
138             /**
139             * @name Inserters
140             *
141             * All the @c operator<< functions (aka formatted output
142             * functions) have some common behavior. Each starts by
143             * constructing a temporary object of type std::basic_ostream::sentry.
144             * This can have several effects, concluding with the setting of a
145             * status flag; see the sentry documentation for more.
146             *
147             * If the sentry status is good, the function tries to generate
148             * whatever data is appropriate for the type of the argument.
149             *
150             * If an exception is thrown during insertion, ios_base::badbit
151             * will be turned on in the stream's error state without causing an
152             * ios_base::failure to be thrown. The original exception will then
153             * be rethrown.
154             */
155              
156             //@{
157             /**
158             * @brief Integer arithmetic inserters
159             * @param __n A variable of builtin integral type.
160             * @return @c *this if successful
161             *
162             * These functions use the stream's current locale (specifically, the
163             * @c num_get facet) to perform numeric formatting.
164             */
165             __ostream_type&
166             operator<<(long __n)
167             { return _M_insert(__n); }
168              
169             __ostream_type&
170             operator<<(unsigned long __n)
171             { return _M_insert(__n); }
172              
173             __ostream_type&
174             operator<<(bool __n)
175             { return _M_insert(__n); }
176              
177             __ostream_type&
178             operator<<(short __n);
179              
180             __ostream_type&
181             operator<<(unsigned short __n)
182             {
183             // _GLIBCXX_RESOLVE_LIB_DEFECTS
184             // 117. basic_ostream uses nonexistent num_put member functions.
185             return _M_insert(static_cast(__n));
186             }
187              
188             __ostream_type&
189             operator<<(int __n);
190              
191             __ostream_type&
192             operator<<(unsigned int __n)
193             {
194             // _GLIBCXX_RESOLVE_LIB_DEFECTS
195             // 117. basic_ostream uses nonexistent num_put member functions.
196 0 0         return _M_insert(static_cast(__n));
    0          
    0          
    0          
    0          
    0          
197             }
198              
199             #ifdef _GLIBCXX_USE_LONG_LONG
200             __ostream_type&
201             operator<<(long long __n)
202             { return _M_insert(__n); }
203              
204             __ostream_type&
205             operator<<(unsigned long long __n)
206             { return _M_insert(__n); }
207             #endif
208             //@}
209              
210             //@{
211             /**
212             * @brief Floating point arithmetic inserters
213             * @param __f A variable of builtin floating point type.
214             * @return @c *this if successful
215             *
216             * These functions use the stream's current locale (specifically, the
217             * @c num_get facet) to perform numeric formatting.
218             */
219             __ostream_type&
220             operator<<(double __f)
221             { return _M_insert(__f); }
222              
223             __ostream_type&
224             operator<<(float __f)
225             {
226             // _GLIBCXX_RESOLVE_LIB_DEFECTS
227             // 117. basic_ostream uses nonexistent num_put member functions.
228             return _M_insert(static_cast(__f));
229             }
230              
231             __ostream_type&
232             operator<<(long double __f)
233             { return _M_insert(__f); }
234             //@}
235              
236             /**
237             * @brief Pointer arithmetic inserters
238             * @param __p A variable of pointer type.
239             * @return @c *this if successful
240             *
241             * These functions use the stream's current locale (specifically, the
242             * @c num_get facet) to perform numeric formatting.
243             */
244             __ostream_type&
245             operator<<(const void* __p)
246             { return _M_insert(__p); }
247              
248             /**
249             * @brief Extracting from another streambuf.
250             * @param __sb A pointer to a streambuf
251             *
252             * This function behaves like one of the basic arithmetic extractors,
253             * in that it also constructs a sentry object and has the same error
254             * handling behavior.
255             *
256             * If @p __sb is NULL, the stream will set failbit in its error state.
257             *
258             * Characters are extracted from @p __sb and inserted into @c *this
259             * until one of the following occurs:
260             *
261             * - the input stream reaches end-of-file,
262             * - insertion into the output sequence fails (in this case, the
263             * character that would have been inserted is not extracted), or
264             * - an exception occurs while getting a character from @p __sb, which
265             * sets failbit in the error state
266             *
267             * If the function inserts no characters, failbit is set.
268             */
269             __ostream_type&
270             operator<<(__streambuf_type* __sb);
271             //@}
272              
273             //@{
274             /**
275             * @name Unformatted Output Functions
276             *
277             * All the unformatted output functions have some common behavior.
278             * Each starts by constructing a temporary object of type
279             * std::basic_ostream::sentry. This has several effects, concluding
280             * with the setting of a status flag; see the sentry documentation
281             * for more.
282             *
283             * If the sentry status is good, the function tries to generate
284             * whatever data is appropriate for the type of the argument.
285             *
286             * If an exception is thrown during insertion, ios_base::badbit
287             * will be turned on in the stream's error state. If badbit is on in
288             * the stream's exceptions mask, the exception will be rethrown
289             * without completing its actions.
290             */
291              
292             /**
293             * @brief Simple insertion.
294             * @param __c The character to insert.
295             * @return *this
296             *
297             * Tries to insert @p __c.
298             *
299             * @note This function is not overloaded on signed char and
300             * unsigned char.
301             */
302             __ostream_type&
303             put(char_type __c);
304              
305             /**
306             * @brief Core write functionality, without sentry.
307             * @param __s The array to insert.
308             * @param __n Maximum number of characters to insert.
309             */
310             void
311             _M_write(const char_type* __s, streamsize __n)
312             {
313             const streamsize __put = this->rdbuf()->sputn(__s, __n);
314             if (__put != __n)
315             this->setstate(ios_base::badbit);
316             }
317              
318             /**
319             * @brief Character string insertion.
320             * @param __s The array to insert.
321             * @param __n Maximum number of characters to insert.
322             * @return *this
323             *
324             * Characters are copied from @p __s and inserted into the stream until
325             * one of the following happens:
326             *
327             * - @p __n characters are inserted
328             * - inserting into the output sequence fails (in this case, badbit
329             * will be set in the stream's error state)
330             *
331             * @note This function is not overloaded on signed char and
332             * unsigned char.
333             */
334             __ostream_type&
335             write(const char_type* __s, streamsize __n);
336             //@}
337              
338             /**
339             * @brief Synchronizing the stream buffer.
340             * @return *this
341             *
342             * If @c rdbuf() is a null pointer, changes nothing.
343             *
344             * Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1,
345             * sets badbit.
346             */
347             __ostream_type&
348             flush();
349              
350             /**
351             * @brief Getting the current write position.
352             * @return A file position object.
353             *
354             * If @c fail() is not false, returns @c pos_type(-1) to indicate
355             * failure. Otherwise returns @c rdbuf()->pubseekoff(0,cur,out).
356             */
357             pos_type
358             tellp();
359              
360             /**
361             * @brief Changing the current write position.
362             * @param __pos A file position object.
363             * @return *this
364             *
365             * If @c fail() is not true, calls @c rdbuf()->pubseekpos(pos). If
366             * that function fails, sets failbit.
367             */
368             __ostream_type&
369             seekp(pos_type);
370              
371             /**
372             * @brief Changing the current write position.
373             * @param __off A file offset object.
374             * @param __dir The direction in which to seek.
375             * @return *this
376             *
377             * If @c fail() is not true, calls @c rdbuf()->pubseekoff(off,dir).
378             * If that function fails, sets failbit.
379             */
380             __ostream_type&
381             seekp(off_type, ios_base::seekdir);
382              
383             protected:
384             basic_ostream()
385             { this->init(0); }
386              
387             #if __cplusplus >= 201103L
388             // Non-standard constructor that does not call init()
389             basic_ostream(basic_iostream<_CharT, _Traits>&) { }
390              
391             basic_ostream(const basic_ostream&) = delete;
392              
393             basic_ostream(basic_ostream&& __rhs)
394             : __ios_type()
395             { __ios_type::move(__rhs); }
396              
397             // 27.7.3.3 Assign/swap
398              
399             basic_ostream& operator=(const basic_ostream&) = delete;
400              
401             basic_ostream&
402             operator=(basic_ostream&& __rhs)
403             {
404             swap(__rhs);
405             return *this;
406             }
407              
408             void
409             swap(basic_ostream& __rhs)
410             { __ios_type::swap(__rhs); }
411             #endif
412              
413             template
414             __ostream_type&
415             _M_insert(_ValueT __v);
416             };
417              
418             /**
419             * @brief Performs setup work for output streams.
420             *
421             * Objects of this class are created before all of the standard
422             * inserters are run. It is responsible for exception-safe prefix and
423             * suffix operations.
424             */
425             template
426             class basic_ostream<_CharT, _Traits>::sentry
427             {
428             // Data Members.
429             bool _M_ok;
430             basic_ostream<_CharT, _Traits>& _M_os;
431              
432             public:
433             /**
434             * @brief The constructor performs preparatory work.
435             * @param __os The output stream to guard.
436             *
437             * If the stream state is good (@a __os.good() is true), then if the
438             * stream is tied to another output stream, @c is.tie()->flush()
439             * is called to synchronize the output sequences.
440             *
441             * If the stream state is still good, then the sentry state becomes
442             * true (@a okay).
443             */
444             explicit
445             sentry(basic_ostream<_CharT, _Traits>& __os);
446              
447             /**
448             * @brief Possibly flushes the stream.
449             *
450             * If @c ios_base::unitbuf is set in @c os.flags(), and
451             * @c std::uncaught_exception() is true, the sentry destructor calls
452             * @c flush() on the output stream.
453             */
454             ~sentry()
455             {
456             // XXX MT
457             if (bool(_M_os.flags() & ios_base::unitbuf) && !uncaught_exception())
458             {
459             // Can't call flush directly or else will get into recursive lock.
460             if (_M_os.rdbuf() && _M_os.rdbuf()->pubsync() == -1)
461             _M_os.setstate(ios_base::badbit);
462             }
463             }
464              
465             /**
466             * @brief Quick status checking.
467             * @return The sentry state.
468             *
469             * For ease of use, sentries may be converted to booleans. The
470             * return value is that of the sentry state (true == okay).
471             */
472             #if __cplusplus >= 201103L
473             explicit
474             #endif
475             operator bool() const
476             { return _M_ok; }
477             };
478              
479             //@{
480             /**
481             * @brief Character inserters
482             * @param __out An output stream.
483             * @param __c A character.
484             * @return out
485             *
486             * Behaves like one of the formatted arithmetic inserters described in
487             * std::basic_ostream. After constructing a sentry object with good
488             * status, this function inserts a single character and any required
489             * padding (as determined by [22.2.2.2.2]). @c __out.width(0) is then
490             * called.
491             *
492             * If @p __c is of type @c char and the character type of the stream is not
493             * @c char, the character is widened before insertion.
494             */
495             template
496             inline basic_ostream<_CharT, _Traits>&
497             operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c)
498             { return __ostream_insert(__out, &__c, 1); }
499              
500             template
501             inline basic_ostream<_CharT, _Traits>&
502             operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
503             { return (__out << __out.widen(__c)); }
504              
505             // Specialization
506             template
507             inline basic_ostream&
508             operator<<(basic_ostream& __out, char __c)
509 0 0         { return __ostream_insert(__out, &__c, 1); }
    0          
    0          
    0          
510              
511             // Signed and unsigned
512             template
513             inline basic_ostream&
514             operator<<(basic_ostream& __out, signed char __c)
515             { return (__out << static_cast(__c)); }
516              
517             template
518             inline basic_ostream&
519             operator<<(basic_ostream& __out, unsigned char __c)
520             { return (__out << static_cast(__c)); }
521             //@}
522              
523             //@{
524             /**
525             * @brief String inserters
526             * @param __out An output stream.
527             * @param __s A character string.
528             * @return out
529             * @pre @p __s must be a non-NULL pointer
530             *
531             * Behaves like one of the formatted arithmetic inserters described in
532             * std::basic_ostream. After constructing a sentry object with good
533             * status, this function inserts @c traits::length(__s) characters starting
534             * at @p __s, widened if necessary, followed by any required padding (as
535             * determined by [22.2.2.2.2]). @c __out.width(0) is then called.
536             */
537             template
538             inline basic_ostream<_CharT, _Traits>&
539             operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s)
540             {
541             if (!__s)
542             __out.setstate(ios_base::badbit);
543             else
544             __ostream_insert(__out, __s,
545             static_cast(_Traits::length(__s)));
546             return __out;
547             }
548              
549             template
550             basic_ostream<_CharT, _Traits> &
551             operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s);
552              
553             // Partial specializations
554             template
555             inline basic_ostream&
556             operator<<(basic_ostream& __out, const char* __s)
557             {
558             if (!__s)
559             __out.setstate(ios_base::badbit);
560             else
561 0 0         __ostream_insert(__out, __s,
    0          
562             static_cast(_Traits::length(__s)));
563             return __out;
564             }
565              
566             // Signed and unsigned
567             template
568             inline basic_ostream&
569             operator<<(basic_ostream& __out, const signed char* __s)
570             { return (__out << reinterpret_cast(__s)); }
571              
572             template
573             inline basic_ostream &
574             operator<<(basic_ostream& __out, const unsigned char* __s)
575             { return (__out << reinterpret_cast(__s)); }
576             //@}
577              
578             // Standard basic_ostream manipulators
579              
580             /**
581             * @brief Write a newline and flush the stream.
582             *
583             * This manipulator is often mistakenly used when a simple newline is
584             * desired, leading to poor buffering performance. See
585             * https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html#io.streambuf.buffering
586             * for more on this subject.
587             */
588             template
589             inline basic_ostream<_CharT, _Traits>&
590             endl(basic_ostream<_CharT, _Traits>& __os)
591             { return flush(__os.put(__os.widen('\n'))); }
592              
593             /**
594             * @brief Write a null character into the output sequence.
595             *
596             * Null character is @c CharT() by definition. For CharT
597             * of @c char, this correctly writes the ASCII @c NUL character
598             * string terminator.
599             */
600             template
601             inline basic_ostream<_CharT, _Traits>&
602             ends(basic_ostream<_CharT, _Traits>& __os)
603             { return __os.put(_CharT()); }
604              
605             /**
606             * @brief Flushes the output stream.
607             *
608             * This manipulator simply calls the stream's @c flush() member function.
609             */
610             template
611             inline basic_ostream<_CharT, _Traits>&
612             flush(basic_ostream<_CharT, _Traits>& __os)
613             { return __os.flush(); }
614              
615             #if __cplusplus >= 201103L
616             /**
617             * @brief Generic inserter for rvalue stream
618             * @param __os An input stream.
619             * @param __x A reference to the object being inserted.
620             * @return os
621             *
622             * This is just a forwarding function to allow insertion to
623             * rvalue streams since they won't bind to the inserter functions
624             * that take an lvalue reference.
625             */
626             template
627             inline basic_ostream<_CharT, _Traits>&
628             operator<<(basic_ostream<_CharT, _Traits>&& __os, const _Tp& __x)
629             {
630             __os << __x;
631             return __os;
632             }
633             #endif // C++11
634              
635             _GLIBCXX_END_NAMESPACE_VERSION
636             } // namespace std
637              
638             #include
639              
640             #endif /* _GLIBCXX_OSTREAM */