xref: /freebsd/contrib/llvm-project/libcxx/include/sstream (revision 77013d11e6483b970af25e13c9b892075742f7e5)
1// -*- C++ -*-
2//===--------------------------- sstream ----------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_SSTREAM
11#define _LIBCPP_SSTREAM
12
13/*
14    sstream synopsis
15
16template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
17class basic_stringbuf
18    : public basic_streambuf<charT, traits>
19{
20public:
21    typedef charT                          char_type;
22    typedef traits                         traits_type;
23    typedef typename traits_type::int_type int_type;
24    typedef typename traits_type::pos_type pos_type;
25    typedef typename traits_type::off_type off_type;
26    typedef Allocator                      allocator_type;
27
28    // 27.8.1.1 [stringbuf.cons], constructors:
29    explicit basic_stringbuf(ios_base::openmode which = ios_base::in | ios_base::out); // before C++20
30    basic_stringbuf() : basic_stringbuf(ios_base::in | ios_base::out) {}               // C++20
31    explicit basic_stringbuf(ios_base::openmode which);                                // C++20
32    explicit basic_stringbuf(const basic_string<char_type, traits_type, allocator_type>& str,
33                             ios_base::openmode which = ios_base::in | ios_base::out);
34    basic_stringbuf(basic_stringbuf&& rhs);
35
36    // 27.8.1.2 Assign and swap:
37    basic_stringbuf& operator=(basic_stringbuf&& rhs);
38    void swap(basic_stringbuf& rhs);
39
40    // 27.8.1.3 Get and set:
41    basic_string<char_type, traits_type, allocator_type> str() const;
42    void str(const basic_string<char_type, traits_type, allocator_type>& s);
43
44protected:
45    // 27.8.1.4 Overridden virtual functions:
46    virtual int_type underflow();
47    virtual int_type pbackfail(int_type c = traits_type::eof());
48    virtual int_type overflow (int_type c = traits_type::eof());
49    virtual basic_streambuf<char_type, traits_type>* setbuf(char_type*, streamsize);
50    virtual pos_type seekoff(off_type off, ios_base::seekdir way,
51                             ios_base::openmode which = ios_base::in | ios_base::out);
52    virtual pos_type seekpos(pos_type sp,
53                             ios_base::openmode which = ios_base::in | ios_base::out);
54};
55
56template <class charT, class traits, class Allocator>
57  void swap(basic_stringbuf<charT, traits, Allocator>& x,
58            basic_stringbuf<charT, traits, Allocator>& y);
59
60typedef basic_stringbuf<char>    stringbuf;
61typedef basic_stringbuf<wchar_t> wstringbuf;
62
63template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
64class basic_istringstream
65    : public basic_istream<charT, traits>
66{
67public:
68    typedef charT                          char_type;
69    typedef traits                         traits_type;
70    typedef typename traits_type::int_type int_type;
71    typedef typename traits_type::pos_type pos_type;
72    typedef typename traits_type::off_type off_type;
73    typedef Allocator                      allocator_type;
74
75    // 27.8.2.1 Constructors:
76    explicit basic_istringstream(ios_base::openmode which = ios_base::in); // before C++20
77    basic_istringstream() : basic_istringstream(ios_base::in) {}           // C++20
78    explicit basic_istringstream(ios_base::openmode which);                // C++20
79
80    explicit basic_istringstream(const basic_string<char_type, traits_type,allocator_type>& str,
81                                 ios_base::openmode which = ios_base::in);
82    basic_istringstream(basic_istringstream&& rhs);
83
84    // 27.8.2.2 Assign and swap:
85    basic_istringstream& operator=(basic_istringstream&& rhs);
86    void swap(basic_istringstream& rhs);
87
88    // 27.8.2.3 Members:
89    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
90    basic_string<char_type, traits_type, allocator_type> str() const;
91    void str(const basic_string<char_type, traits_type, allocator_type>& s);
92};
93
94template <class charT, class traits, class Allocator>
95  void swap(basic_istringstream<charT, traits, Allocator>& x,
96            basic_istringstream<charT, traits, Allocator>& y);
97
98typedef basic_istringstream<char>    istringstream;
99typedef basic_istringstream<wchar_t> wistringstream;
100
101template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
102class basic_ostringstream
103    : public basic_ostream<charT, traits>
104{
105public:
106    // types:
107    typedef charT                          char_type;
108    typedef traits                         traits_type;
109    typedef typename traits_type::int_type int_type;
110    typedef typename traits_type::pos_type pos_type;
111    typedef typename traits_type::off_type off_type;
112    typedef Allocator                      allocator_type;
113
114    // 27.8.3.1 Constructors/destructor:
115    explicit basic_ostringstream(ios_base::openmode which = ios_base::out); // before C++20
116    basic_ostringstream() : basic_ostringstream(ios_base::out) {}           // C++20
117    explicit basic_ostringstream(ios_base::openmode which);                 // C++20
118
119    explicit basic_ostringstream(const basic_string<char_type, traits_type, allocator_type>& str,
120                                 ios_base::openmode which = ios_base::out);
121    basic_ostringstream(basic_ostringstream&& rhs);
122
123    // 27.8.3.2 Assign/swap:
124    basic_ostringstream& operator=(basic_ostringstream&& rhs);
125    void swap(basic_ostringstream& rhs);
126
127    // 27.8.3.3 Members:
128    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
129    basic_string<char_type, traits_type, allocator_type> str() const;
130    void str(const basic_string<char_type, traits_type, allocator_type>& s);
131};
132
133template <class charT, class traits, class Allocator>
134  void swap(basic_ostringstream<charT, traits, Allocator>& x,
135            basic_ostringstream<charT, traits, Allocator>& y);
136
137typedef basic_ostringstream<char>    ostringstream;
138typedef basic_ostringstream<wchar_t> wostringstream;
139
140template <class charT, class traits = char_traits<charT>, class Allocator = allocator<charT> >
141class basic_stringstream
142    : public basic_iostream<charT, traits>
143{
144public:
145    // types:
146    typedef charT                          char_type;
147    typedef traits                         traits_type;
148    typedef typename traits_type::int_type int_type;
149    typedef typename traits_type::pos_type pos_type;
150    typedef typename traits_type::off_type off_type;
151    typedef Allocator                      allocator_type;
152
153    // constructors/destructor
154    explicit basic_stringstream(ios_base::openmode which = ios_base::out | ios_base::in); // before C++20
155    basic_stringstream() : basic_stringstream(ios_base::out | ios_base::in) {}            // C++20
156    explicit basic_stringstream(ios_base::openmode which);                                // C++20
157
158    explicit basic_stringstream(const basic_string<char_type, traits_type, allocator_type>& str,
159                                ios_base::openmode which = ios_base::out|ios_base::in);
160    basic_stringstream(basic_stringstream&& rhs);
161
162    // 27.8.5.1 Assign/swap:
163    basic_stringstream& operator=(basic_stringstream&& rhs);
164    void swap(basic_stringstream& rhs);
165
166    // Members:
167    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const;
168    basic_string<char_type, traits_type, allocator_type> str() const;
169    void str(const basic_string<char_type, traits_type, allocator_type>& str);
170};
171
172template <class charT, class traits, class Allocator>
173  void swap(basic_stringstream<charT, traits, Allocator>& x,
174            basic_stringstream<charT, traits, Allocator>& y);
175
176typedef basic_stringstream<char>    stringstream;
177typedef basic_stringstream<wchar_t> wstringstream;
178
179}  // std
180
181*/
182
183#include <__config>
184#include <ostream>
185#include <istream>
186#include <string>
187
188#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
189#pragma GCC system_header
190#endif
191
192_LIBCPP_PUSH_MACROS
193#include <__undef_macros>
194
195
196_LIBCPP_BEGIN_NAMESPACE_STD
197
198// basic_stringbuf
199
200template <class _CharT, class _Traits, class _Allocator>
201class _LIBCPP_TEMPLATE_VIS basic_stringbuf
202    : public basic_streambuf<_CharT, _Traits>
203{
204public:
205    typedef _CharT                         char_type;
206    typedef _Traits                        traits_type;
207    typedef typename traits_type::int_type int_type;
208    typedef typename traits_type::pos_type pos_type;
209    typedef typename traits_type::off_type off_type;
210    typedef _Allocator                     allocator_type;
211
212    typedef basic_string<char_type, traits_type, allocator_type> string_type;
213
214private:
215
216    string_type __str_;
217    mutable char_type* __hm_;
218    ios_base::openmode __mode_;
219
220public:
221    // 30.8.2.1 [stringbuf.cons], constructors
222#ifndef _LIBCPP_CXX03_LANG
223    _LIBCPP_INLINE_VISIBILITY
224    basic_stringbuf() : basic_stringbuf(ios_base::in | ios_base::out) {}
225
226    _LIBCPP_INLINE_VISIBILITY
227    explicit basic_stringbuf(ios_base::openmode __wch)
228        : __hm_(nullptr), __mode_(__wch) {}
229#else
230    _LIBCPP_INLINE_VISIBILITY
231    explicit basic_stringbuf(ios_base::openmode __wch = ios_base::in |
232                                                        ios_base::out)
233        : __hm_(nullptr), __mode_(__wch) {}
234#endif
235
236    _LIBCPP_INLINE_VISIBILITY
237    explicit basic_stringbuf(const string_type& __s,
238                             ios_base::openmode __wch = ios_base::in | ios_base::out)
239        : __str_(__s.get_allocator()), __hm_(nullptr), __mode_(__wch)
240    {
241        str(__s);
242    }
243
244    basic_stringbuf(basic_stringbuf&& __rhs);
245
246    // 27.8.1.2 Assign and swap:
247    basic_stringbuf& operator=(basic_stringbuf&& __rhs);
248    void swap(basic_stringbuf& __rhs);
249
250    // 27.8.1.3 Get and set:
251    string_type str() const;
252    void str(const string_type& __s);
253
254protected:
255    // 27.8.1.4 Overridden virtual functions:
256    virtual int_type underflow();
257    virtual int_type pbackfail(int_type __c = traits_type::eof());
258    virtual int_type overflow (int_type __c = traits_type::eof());
259    virtual pos_type seekoff(off_type __off, ios_base::seekdir __way,
260                             ios_base::openmode __wch = ios_base::in | ios_base::out);
261    _LIBCPP_INLINE_VISIBILITY
262    virtual pos_type seekpos(pos_type __sp,
263                             ios_base::openmode __wch = ios_base::in | ios_base::out) {
264        return seekoff(__sp, ios_base::beg, __wch);
265    }
266};
267
268template <class _CharT, class _Traits, class _Allocator>
269basic_stringbuf<_CharT, _Traits, _Allocator>::basic_stringbuf(basic_stringbuf&& __rhs)
270    : __mode_(__rhs.__mode_)
271{
272    char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
273    ptrdiff_t __binp = -1;
274    ptrdiff_t __ninp = -1;
275    ptrdiff_t __einp = -1;
276    if (__rhs.eback() != nullptr)
277    {
278        __binp = __rhs.eback() - __p;
279        __ninp = __rhs.gptr() - __p;
280        __einp = __rhs.egptr() - __p;
281    }
282    ptrdiff_t __bout = -1;
283    ptrdiff_t __nout = -1;
284    ptrdiff_t __eout = -1;
285    if (__rhs.pbase() != nullptr)
286    {
287        __bout = __rhs.pbase() - __p;
288        __nout = __rhs.pptr() - __p;
289        __eout = __rhs.epptr() - __p;
290    }
291    ptrdiff_t __hm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
292    __str_ = _VSTD::move(__rhs.__str_);
293    __p = const_cast<char_type*>(__str_.data());
294    if (__binp != -1)
295        this->setg(__p + __binp, __p + __ninp, __p + __einp);
296    if (__bout != -1)
297    {
298        this->setp(__p + __bout, __p + __eout);
299        this->__pbump(__nout);
300    }
301    __hm_ = __hm == -1 ? nullptr : __p + __hm;
302    __p = const_cast<char_type*>(__rhs.__str_.data());
303    __rhs.setg(__p, __p, __p);
304    __rhs.setp(__p, __p);
305    __rhs.__hm_ = __p;
306    this->pubimbue(__rhs.getloc());
307}
308
309template <class _CharT, class _Traits, class _Allocator>
310basic_stringbuf<_CharT, _Traits, _Allocator>&
311basic_stringbuf<_CharT, _Traits, _Allocator>::operator=(basic_stringbuf&& __rhs)
312{
313    char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
314    ptrdiff_t __binp = -1;
315    ptrdiff_t __ninp = -1;
316    ptrdiff_t __einp = -1;
317    if (__rhs.eback() != nullptr)
318    {
319        __binp = __rhs.eback() - __p;
320        __ninp = __rhs.gptr() - __p;
321        __einp = __rhs.egptr() - __p;
322    }
323    ptrdiff_t __bout = -1;
324    ptrdiff_t __nout = -1;
325    ptrdiff_t __eout = -1;
326    if (__rhs.pbase() != nullptr)
327    {
328        __bout = __rhs.pbase() - __p;
329        __nout = __rhs.pptr() - __p;
330        __eout = __rhs.epptr() - __p;
331    }
332    ptrdiff_t __hm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
333    __str_ = _VSTD::move(__rhs.__str_);
334    __p = const_cast<char_type*>(__str_.data());
335    if (__binp != -1)
336        this->setg(__p + __binp, __p + __ninp, __p + __einp);
337    else
338        this->setg(nullptr, nullptr, nullptr);
339    if (__bout != -1)
340    {
341        this->setp(__p + __bout, __p + __eout);
342        this->__pbump(__nout);
343    }
344    else
345        this->setp(nullptr, nullptr);
346
347    __hm_ = __hm == -1 ? nullptr : __p + __hm;
348    __mode_ = __rhs.__mode_;
349    __p = const_cast<char_type*>(__rhs.__str_.data());
350    __rhs.setg(__p, __p, __p);
351    __rhs.setp(__p, __p);
352    __rhs.__hm_ = __p;
353    this->pubimbue(__rhs.getloc());
354    return *this;
355}
356
357template <class _CharT, class _Traits, class _Allocator>
358void
359basic_stringbuf<_CharT, _Traits, _Allocator>::swap(basic_stringbuf& __rhs)
360{
361    char_type* __p = const_cast<char_type*>(__rhs.__str_.data());
362    ptrdiff_t __rbinp = -1;
363    ptrdiff_t __rninp = -1;
364    ptrdiff_t __reinp = -1;
365    if (__rhs.eback() != nullptr)
366    {
367        __rbinp = __rhs.eback() - __p;
368        __rninp = __rhs.gptr() - __p;
369        __reinp = __rhs.egptr() - __p;
370    }
371    ptrdiff_t __rbout = -1;
372    ptrdiff_t __rnout = -1;
373    ptrdiff_t __reout = -1;
374    if (__rhs.pbase() != nullptr)
375    {
376        __rbout = __rhs.pbase() - __p;
377        __rnout = __rhs.pptr() - __p;
378        __reout = __rhs.epptr() - __p;
379    }
380    ptrdiff_t __rhm = __rhs.__hm_ == nullptr ? -1 : __rhs.__hm_ - __p;
381    __p = const_cast<char_type*>(__str_.data());
382    ptrdiff_t __lbinp = -1;
383    ptrdiff_t __lninp = -1;
384    ptrdiff_t __leinp = -1;
385    if (this->eback() != nullptr)
386    {
387        __lbinp = this->eback() - __p;
388        __lninp = this->gptr() - __p;
389        __leinp = this->egptr() - __p;
390    }
391    ptrdiff_t __lbout = -1;
392    ptrdiff_t __lnout = -1;
393    ptrdiff_t __leout = -1;
394    if (this->pbase() != nullptr)
395    {
396        __lbout = this->pbase() - __p;
397        __lnout = this->pptr() - __p;
398        __leout = this->epptr() - __p;
399    }
400    ptrdiff_t __lhm = __hm_ == nullptr ? -1 : __hm_ - __p;
401    _VSTD::swap(__mode_, __rhs.__mode_);
402    __str_.swap(__rhs.__str_);
403    __p = const_cast<char_type*>(__str_.data());
404    if (__rbinp != -1)
405        this->setg(__p + __rbinp, __p + __rninp, __p + __reinp);
406    else
407        this->setg(nullptr, nullptr, nullptr);
408    if (__rbout != -1)
409    {
410        this->setp(__p + __rbout, __p + __reout);
411        this->__pbump(__rnout);
412    }
413    else
414        this->setp(nullptr, nullptr);
415    __hm_ = __rhm == -1 ? nullptr : __p + __rhm;
416    __p = const_cast<char_type*>(__rhs.__str_.data());
417    if (__lbinp != -1)
418        __rhs.setg(__p + __lbinp, __p + __lninp, __p + __leinp);
419    else
420        __rhs.setg(nullptr, nullptr, nullptr);
421    if (__lbout != -1)
422    {
423        __rhs.setp(__p + __lbout, __p + __leout);
424        __rhs.__pbump(__lnout);
425    }
426    else
427        __rhs.setp(nullptr, nullptr);
428    __rhs.__hm_ = __lhm == -1 ? nullptr : __p + __lhm;
429    locale __tl = __rhs.getloc();
430    __rhs.pubimbue(this->getloc());
431    this->pubimbue(__tl);
432}
433
434template <class _CharT, class _Traits, class _Allocator>
435inline _LIBCPP_INLINE_VISIBILITY
436void
437swap(basic_stringbuf<_CharT, _Traits, _Allocator>& __x,
438     basic_stringbuf<_CharT, _Traits, _Allocator>& __y)
439{
440    __x.swap(__y);
441}
442
443template <class _CharT, class _Traits, class _Allocator>
444basic_string<_CharT, _Traits, _Allocator>
445basic_stringbuf<_CharT, _Traits, _Allocator>::str() const
446{
447    if (__mode_ & ios_base::out)
448    {
449        if (__hm_ < this->pptr())
450            __hm_ = this->pptr();
451        return string_type(this->pbase(), __hm_, __str_.get_allocator());
452    }
453    else if (__mode_ & ios_base::in)
454        return string_type(this->eback(), this->egptr(), __str_.get_allocator());
455    return string_type(__str_.get_allocator());
456}
457
458template <class _CharT, class _Traits, class _Allocator>
459void
460basic_stringbuf<_CharT, _Traits, _Allocator>::str(const string_type& __s)
461{
462    __str_ = __s;
463    __hm_ = nullptr;
464    if (__mode_ & ios_base::in)
465    {
466        __hm_ = const_cast<char_type*>(__str_.data()) + __str_.size();
467        this->setg(const_cast<char_type*>(__str_.data()),
468                   const_cast<char_type*>(__str_.data()),
469                   __hm_);
470    }
471    if (__mode_ & ios_base::out)
472    {
473        typename string_type::size_type __sz = __str_.size();
474        __hm_ = const_cast<char_type*>(__str_.data()) + __sz;
475        __str_.resize(__str_.capacity());
476        this->setp(const_cast<char_type*>(__str_.data()),
477                   const_cast<char_type*>(__str_.data()) + __str_.size());
478        if (__mode_ & (ios_base::app | ios_base::ate))
479        {
480            while (__sz > INT_MAX)
481            {
482                this->pbump(INT_MAX);
483                __sz -= INT_MAX;
484            }
485            if (__sz > 0)
486                this->pbump(__sz);
487        }
488    }
489}
490
491template <class _CharT, class _Traits, class _Allocator>
492typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
493basic_stringbuf<_CharT, _Traits, _Allocator>::underflow()
494{
495    if (__hm_ < this->pptr())
496        __hm_ = this->pptr();
497    if (__mode_ & ios_base::in)
498    {
499        if (this->egptr() < __hm_)
500            this->setg(this->eback(), this->gptr(), __hm_);
501        if (this->gptr() < this->egptr())
502            return traits_type::to_int_type(*this->gptr());
503    }
504    return traits_type::eof();
505}
506
507template <class _CharT, class _Traits, class _Allocator>
508typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
509basic_stringbuf<_CharT, _Traits, _Allocator>::pbackfail(int_type __c)
510{
511    if (__hm_ < this->pptr())
512        __hm_ = this->pptr();
513    if (this->eback() < this->gptr())
514    {
515        if (traits_type::eq_int_type(__c, traits_type::eof()))
516        {
517            this->setg(this->eback(), this->gptr()-1, __hm_);
518            return traits_type::not_eof(__c);
519        }
520        if ((__mode_ & ios_base::out) ||
521            traits_type::eq(traits_type::to_char_type(__c), this->gptr()[-1]))
522        {
523            this->setg(this->eback(), this->gptr()-1, __hm_);
524            *this->gptr() = traits_type::to_char_type(__c);
525            return __c;
526        }
527    }
528    return traits_type::eof();
529}
530
531template <class _CharT, class _Traits, class _Allocator>
532typename basic_stringbuf<_CharT, _Traits, _Allocator>::int_type
533basic_stringbuf<_CharT, _Traits, _Allocator>::overflow(int_type __c)
534{
535    if (!traits_type::eq_int_type(__c, traits_type::eof()))
536    {
537        ptrdiff_t __ninp = this->gptr()  - this->eback();
538        if (this->pptr() == this->epptr())
539        {
540            if (!(__mode_ & ios_base::out))
541                return traits_type::eof();
542#ifndef _LIBCPP_NO_EXCEPTIONS
543            try
544            {
545#endif  // _LIBCPP_NO_EXCEPTIONS
546                ptrdiff_t __nout = this->pptr()  - this->pbase();
547                ptrdiff_t __hm = __hm_ - this->pbase();
548                __str_.push_back(char_type());
549                __str_.resize(__str_.capacity());
550                char_type* __p = const_cast<char_type*>(__str_.data());
551                this->setp(__p, __p + __str_.size());
552                this->__pbump(__nout);
553                __hm_ = this->pbase() + __hm;
554#ifndef _LIBCPP_NO_EXCEPTIONS
555            }
556            catch (...)
557            {
558                return traits_type::eof();
559            }
560#endif  // _LIBCPP_NO_EXCEPTIONS
561        }
562        __hm_ = _VSTD::max(this->pptr() + 1, __hm_);
563        if (__mode_ & ios_base::in)
564        {
565            char_type* __p = const_cast<char_type*>(__str_.data());
566            this->setg(__p, __p + __ninp, __hm_);
567        }
568        return this->sputc(traits_type::to_char_type(__c));
569    }
570    return traits_type::not_eof(__c);
571}
572
573template <class _CharT, class _Traits, class _Allocator>
574typename basic_stringbuf<_CharT, _Traits, _Allocator>::pos_type
575basic_stringbuf<_CharT, _Traits, _Allocator>::seekoff(off_type __off,
576                                                      ios_base::seekdir __way,
577                                                      ios_base::openmode __wch)
578{
579    if (__hm_ < this->pptr())
580        __hm_ = this->pptr();
581    if ((__wch & (ios_base::in | ios_base::out)) == 0)
582        return pos_type(-1);
583    if ((__wch & (ios_base::in | ios_base::out)) == (ios_base::in | ios_base::out)
584        && __way == ios_base::cur)
585        return pos_type(-1);
586    const ptrdiff_t __hm = __hm_ == nullptr ? 0 : __hm_ - __str_.data();
587    off_type __noff;
588    switch (__way)
589    {
590    case ios_base::beg:
591        __noff = 0;
592        break;
593    case ios_base::cur:
594        if (__wch & ios_base::in)
595            __noff = this->gptr() - this->eback();
596        else
597            __noff = this->pptr() - this->pbase();
598        break;
599    case ios_base::end:
600        __noff = __hm;
601        break;
602    default:
603        return pos_type(-1);
604    }
605    __noff += __off;
606    if (__noff < 0 || __hm < __noff)
607        return pos_type(-1);
608    if (__noff != 0)
609    {
610        if ((__wch & ios_base::in) && this->gptr() == nullptr)
611            return pos_type(-1);
612        if ((__wch & ios_base::out) && this->pptr() == nullptr)
613            return pos_type(-1);
614    }
615    if (__wch & ios_base::in)
616        this->setg(this->eback(), this->eback() + __noff, __hm_);
617    if (__wch & ios_base::out)
618    {
619        this->setp(this->pbase(), this->epptr());
620        this->pbump(__noff);
621    }
622    return pos_type(__noff);
623}
624
625// basic_istringstream
626
627template <class _CharT, class _Traits, class _Allocator>
628class _LIBCPP_TEMPLATE_VIS basic_istringstream
629    : public basic_istream<_CharT, _Traits>
630{
631public:
632    typedef _CharT                         char_type;
633    typedef _Traits                        traits_type;
634    typedef typename traits_type::int_type int_type;
635    typedef typename traits_type::pos_type pos_type;
636    typedef typename traits_type::off_type off_type;
637    typedef _Allocator                     allocator_type;
638
639    typedef basic_string<char_type, traits_type, allocator_type> string_type;
640
641private:
642    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
643
644public:
645    // 30.8.3.1 [istringstream.cons], constructors
646#ifndef _LIBCPP_CXX03_LANG
647    _LIBCPP_INLINE_VISIBILITY
648    basic_istringstream() : basic_istringstream(ios_base::in) {}
649
650    _LIBCPP_INLINE_VISIBILITY
651    explicit basic_istringstream(ios_base::openmode __wch)
652        : basic_istream<_CharT, _Traits>(&__sb_), __sb_(__wch | ios_base::in) {}
653#else
654    _LIBCPP_INLINE_VISIBILITY
655    explicit basic_istringstream(ios_base::openmode __wch = ios_base::in)
656        : basic_istream<_CharT, _Traits>(&__sb_), __sb_(__wch | ios_base::in) {}
657#endif
658
659    _LIBCPP_INLINE_VISIBILITY
660    explicit basic_istringstream(const string_type& __s,
661                                 ios_base::openmode __wch = ios_base::in)
662        : basic_istream<_CharT, _Traits>(&__sb_)
663        , __sb_(__s, __wch | ios_base::in)
664    { }
665
666    _LIBCPP_INLINE_VISIBILITY
667    basic_istringstream(basic_istringstream&& __rhs)
668        : basic_istream<_CharT, _Traits>(_VSTD::move(__rhs))
669        , __sb_(_VSTD::move(__rhs.__sb_))
670    {
671        basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
672    }
673
674    // 27.8.2.2 Assign and swap:
675    basic_istringstream& operator=(basic_istringstream&& __rhs) {
676        basic_istream<char_type, traits_type>::operator=(_VSTD::move(__rhs));
677        __sb_ = _VSTD::move(__rhs.__sb_);
678        return *this;
679    }
680    _LIBCPP_INLINE_VISIBILITY
681    void swap(basic_istringstream& __rhs) {
682        basic_istream<char_type, traits_type>::swap(__rhs);
683        __sb_.swap(__rhs.__sb_);
684    }
685
686    // 27.8.2.3 Members:
687    _LIBCPP_INLINE_VISIBILITY
688    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
689        return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
690    }
691    _LIBCPP_INLINE_VISIBILITY
692    string_type str() const {
693        return __sb_.str();
694    }
695    _LIBCPP_INLINE_VISIBILITY
696    void str(const string_type& __s) {
697        __sb_.str(__s);
698    }
699};
700
701template <class _CharT, class _Traits, class _Allocator>
702inline _LIBCPP_INLINE_VISIBILITY
703void
704swap(basic_istringstream<_CharT, _Traits, _Allocator>& __x,
705     basic_istringstream<_CharT, _Traits, _Allocator>& __y)
706{
707    __x.swap(__y);
708}
709
710// basic_ostringstream
711
712template <class _CharT, class _Traits, class _Allocator>
713class _LIBCPP_TEMPLATE_VIS basic_ostringstream
714    : public basic_ostream<_CharT, _Traits>
715{
716public:
717    typedef _CharT                         char_type;
718    typedef _Traits                        traits_type;
719    typedef typename traits_type::int_type int_type;
720    typedef typename traits_type::pos_type pos_type;
721    typedef typename traits_type::off_type off_type;
722    typedef _Allocator                     allocator_type;
723
724    typedef basic_string<char_type, traits_type, allocator_type> string_type;
725
726private:
727    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
728
729public:
730    // 30.8.4.1 [ostringstream.cons], constructors
731#ifndef _LIBCPP_CXX03_LANG
732    _LIBCPP_INLINE_VISIBILITY
733    basic_ostringstream() : basic_ostringstream(ios_base::out) {}
734
735    _LIBCPP_INLINE_VISIBILITY
736    explicit basic_ostringstream(ios_base::openmode __wch)
737        : basic_ostream<_CharT, _Traits>(&__sb_),
738          __sb_(__wch | ios_base::out) {}
739#else
740    _LIBCPP_INLINE_VISIBILITY
741    explicit basic_ostringstream(ios_base::openmode __wch = ios_base::out)
742        : basic_ostream<_CharT, _Traits>(&__sb_),
743          __sb_(__wch | ios_base::out) {}
744#endif
745
746    _LIBCPP_INLINE_VISIBILITY
747    explicit basic_ostringstream(const string_type& __s,
748                                 ios_base::openmode __wch = ios_base::out)
749        : basic_ostream<_CharT, _Traits>(&__sb_)
750        , __sb_(__s, __wch | ios_base::out)
751    { }
752
753    _LIBCPP_INLINE_VISIBILITY
754    basic_ostringstream(basic_ostringstream&& __rhs)
755        : basic_ostream<_CharT, _Traits>(_VSTD::move(__rhs))
756        , __sb_(_VSTD::move(__rhs.__sb_))
757    {
758        basic_ostream<_CharT, _Traits>::set_rdbuf(&__sb_);
759    }
760
761    // 27.8.2.2 Assign and swap:
762    basic_ostringstream& operator=(basic_ostringstream&& __rhs) {
763        basic_ostream<char_type, traits_type>::operator=(_VSTD::move(__rhs));
764        __sb_ = _VSTD::move(__rhs.__sb_);
765        return *this;
766    }
767
768    _LIBCPP_INLINE_VISIBILITY
769    void swap(basic_ostringstream& __rhs) {
770        basic_ostream<char_type, traits_type>::swap(__rhs);
771        __sb_.swap(__rhs.__sb_);
772    }
773
774    // 27.8.2.3 Members:
775    _LIBCPP_INLINE_VISIBILITY
776    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
777        return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
778    }
779    _LIBCPP_INLINE_VISIBILITY
780    string_type str() const {
781        return __sb_.str();
782    }
783    _LIBCPP_INLINE_VISIBILITY
784    void str(const string_type& __s) {
785        __sb_.str(__s);
786    }
787};
788
789template <class _CharT, class _Traits, class _Allocator>
790inline _LIBCPP_INLINE_VISIBILITY
791void
792swap(basic_ostringstream<_CharT, _Traits, _Allocator>& __x,
793     basic_ostringstream<_CharT, _Traits, _Allocator>& __y)
794{
795    __x.swap(__y);
796}
797
798// basic_stringstream
799
800template <class _CharT, class _Traits, class _Allocator>
801class _LIBCPP_TEMPLATE_VIS basic_stringstream
802    : public basic_iostream<_CharT, _Traits>
803{
804public:
805    typedef _CharT                         char_type;
806    typedef _Traits                        traits_type;
807    typedef typename traits_type::int_type int_type;
808    typedef typename traits_type::pos_type pos_type;
809    typedef typename traits_type::off_type off_type;
810    typedef _Allocator                     allocator_type;
811
812    typedef basic_string<char_type, traits_type, allocator_type> string_type;
813
814private:
815    basic_stringbuf<char_type, traits_type, allocator_type> __sb_;
816
817public:
818    // 30.8.5.1 [stringstream.cons], constructors
819#ifndef _LIBCPP_CXX03_LANG
820    _LIBCPP_INLINE_VISIBILITY
821    basic_stringstream() : basic_stringstream(ios_base::in | ios_base::out) {}
822
823    _LIBCPP_INLINE_VISIBILITY
824    explicit basic_stringstream(ios_base::openmode __wch)
825        : basic_iostream<_CharT, _Traits>(&__sb_), __sb_(__wch) {}
826#else
827    _LIBCPP_INLINE_VISIBILITY
828    explicit basic_stringstream(ios_base::openmode __wch = ios_base::in |
829                                                           ios_base::out)
830        : basic_iostream<_CharT, _Traits>(&__sb_), __sb_(__wch) {}
831#endif
832
833    _LIBCPP_INLINE_VISIBILITY
834    explicit basic_stringstream(const string_type& __s,
835                                ios_base::openmode __wch = ios_base::in | ios_base::out)
836        : basic_iostream<_CharT, _Traits>(&__sb_)
837        , __sb_(__s, __wch)
838    { }
839
840    _LIBCPP_INLINE_VISIBILITY
841    basic_stringstream(basic_stringstream&& __rhs)
842        : basic_iostream<_CharT, _Traits>(_VSTD::move(__rhs))
843        , __sb_(_VSTD::move(__rhs.__sb_))
844    {
845        basic_istream<_CharT, _Traits>::set_rdbuf(&__sb_);
846    }
847
848    // 27.8.2.2 Assign and swap:
849    basic_stringstream& operator=(basic_stringstream&& __rhs) {
850        basic_iostream<char_type, traits_type>::operator=(_VSTD::move(__rhs));
851        __sb_ = _VSTD::move(__rhs.__sb_);
852        return *this;
853    }
854    _LIBCPP_INLINE_VISIBILITY
855    void swap(basic_stringstream& __rhs) {
856        basic_iostream<char_type, traits_type>::swap(__rhs);
857        __sb_.swap(__rhs.__sb_);
858    }
859
860    // 27.8.2.3 Members:
861    _LIBCPP_INLINE_VISIBILITY
862    basic_stringbuf<char_type, traits_type, allocator_type>* rdbuf() const {
863        return const_cast<basic_stringbuf<char_type, traits_type, allocator_type>*>(&__sb_);
864    }
865    _LIBCPP_INLINE_VISIBILITY
866    string_type str() const {
867        return __sb_.str();
868    }
869    _LIBCPP_INLINE_VISIBILITY
870    void str(const string_type& __s) {
871        __sb_.str(__s);
872    }
873};
874
875template <class _CharT, class _Traits, class _Allocator>
876inline _LIBCPP_INLINE_VISIBILITY
877void
878swap(basic_stringstream<_CharT, _Traits, _Allocator>& __x,
879     basic_stringstream<_CharT, _Traits, _Allocator>& __y)
880{
881    __x.swap(__y);
882}
883
884#if defined(_LIBCPP_ABI_ENABLE_ADDITIONAL_IOSTREAM_EXPLICIT_INSTANTIATIONS_1)
885_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_stringbuf<char>)
886_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_stringstream<char>)
887_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ostringstream<char>)
888_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_istringstream<char>)
889#endif
890
891_LIBCPP_END_NAMESPACE_STD
892
893_LIBCPP_POP_MACROS
894
895#endif  // _LIBCPP_SSTREAM
896