1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
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_STREAMBUF
11#define _LIBCPP_STREAMBUF
12
13/*
14    streambuf synopsis
15
16namespace std
17{
18
19template <class charT, class traits = char_traits<charT> >
20class basic_streambuf
21{
22public:
23    // types:
24    typedef charT char_type;
25    typedef traits traits_type;
26    typedef typename traits_type::int_type int_type;
27    typedef typename traits_type::pos_type pos_type;
28    typedef typename traits_type::off_type off_type;
29
30    virtual ~basic_streambuf();
31
32    // 27.6.2.2.1 locales:
33    locale pubimbue(const locale& loc);
34    locale getloc() const;
35
36    // 27.6.2.2.2 buffer and positioning:
37    basic_streambuf* pubsetbuf(char_type* s, streamsize n);
38    pos_type pubseekoff(off_type off, ios_base::seekdir way,
39                        ios_base::openmode which = ios_base::in | ios_base::out);
40    pos_type pubseekpos(pos_type sp,
41                        ios_base::openmode which = ios_base::in | ios_base::out);
42    int pubsync();
43
44    // Get and put areas:
45    // 27.6.2.2.3 Get area:
46    streamsize in_avail();
47    int_type snextc();
48    int_type sbumpc();
49    int_type sgetc();
50    streamsize sgetn(char_type* s, streamsize n);
51
52    // 27.6.2.2.4 Putback:
53    int_type sputbackc(char_type c);
54    int_type sungetc();
55
56    // 27.6.2.2.5 Put area:
57    int_type sputc(char_type c);
58    streamsize sputn(const char_type* s, streamsize n);
59
60protected:
61    basic_streambuf();
62    basic_streambuf(const basic_streambuf& rhs);
63    basic_streambuf& operator=(const basic_streambuf& rhs);
64    void swap(basic_streambuf& rhs);
65
66    // 27.6.2.3.2 Get area:
67    char_type* eback() const;
68    char_type* gptr() const;
69    char_type* egptr() const;
70    void gbump(int n);
71    void setg(char_type* gbeg, char_type* gnext, char_type* gend);
72
73    // 27.6.2.3.3 Put area:
74    char_type* pbase() const;
75    char_type* pptr() const;
76    char_type* epptr() const;
77    void pbump(int n);
78    void setp(char_type* pbeg, char_type* pend);
79
80    // 27.6.2.4 virtual functions:
81    // 27.6.2.4.1 Locales:
82    virtual void imbue(const locale& loc);
83
84    // 27.6.2.4.2 Buffer management and positioning:
85    virtual basic_streambuf* setbuf(char_type* s, streamsize n);
86    virtual pos_type seekoff(off_type off, ios_base::seekdir way,
87                             ios_base::openmode which = ios_base::in | ios_base::out);
88    virtual pos_type seekpos(pos_type sp,
89                             ios_base::openmode which = ios_base::in | ios_base::out);
90    virtual int sync();
91
92    // 27.6.2.4.3 Get area:
93    virtual streamsize showmanyc();
94    virtual streamsize xsgetn(char_type* s, streamsize n);
95    virtual int_type underflow();
96    virtual int_type uflow();
97
98    // 27.6.2.4.4 Putback:
99    virtual int_type pbackfail(int_type c = traits_type::eof());
100
101    // 27.6.2.4.5 Put area:
102    virtual streamsize xsputn(const char_type* s, streamsize n);
103    virtual int_type overflow (int_type c = traits_type::eof());
104};
105
106}  // std
107
108*/
109
110#include <__config>
111#include <ios>
112#include <iosfwd>
113#include <version>
114
115#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
116#pragma GCC system_header
117#endif
118
119_LIBCPP_PUSH_MACROS
120#include <__undef_macros>
121
122_LIBCPP_BEGIN_NAMESPACE_STD
123
124template <class _CharT, class _Traits>
125class _LIBCPP_TEMPLATE_VIS basic_streambuf
126{
127public:
128    // types:
129    typedef _CharT                         char_type;
130    typedef _Traits                        traits_type;
131    typedef typename traits_type::int_type int_type;
132    typedef typename traits_type::pos_type pos_type;
133    typedef typename traits_type::off_type off_type;
134
135    static_assert((is_same<_CharT, typename traits_type::char_type>::value),
136                  "traits_type::char_type must be the same type as CharT");
137
138    virtual ~basic_streambuf();
139
140    // 27.6.2.2.1 locales:
141    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
142    locale pubimbue(const locale& __loc) {
143        imbue(__loc);
144        locale __r = __loc_;
145        __loc_ = __loc;
146        return __r;
147    }
148
149    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
150    locale getloc() const { return __loc_; }
151
152    // 27.6.2.2.2 buffer and positioning:
153    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
154    basic_streambuf* pubsetbuf(char_type* __s, streamsize __n)
155    { return setbuf(__s, __n); }
156
157    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
158    pos_type pubseekoff(off_type __off, ios_base::seekdir __way,
159                        ios_base::openmode __which = ios_base::in | ios_base::out)
160    { return seekoff(__off, __way, __which); }
161
162    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
163    pos_type pubseekpos(pos_type __sp,
164                        ios_base::openmode __which = ios_base::in | ios_base::out)
165    { return seekpos(__sp, __which); }
166
167    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
168    int pubsync() { return sync(); }
169
170    // Get and put areas:
171    // 27.6.2.2.3 Get area:
172    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
173    streamsize in_avail() {
174        if (__ninp_ < __einp_)
175            return static_cast<streamsize>(__einp_ - __ninp_);
176        return showmanyc();
177    }
178
179    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
180    int_type snextc() {
181        if (sbumpc() == traits_type::eof())
182            return traits_type::eof();
183        return sgetc();
184    }
185
186    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
187    int_type sbumpc() {
188        if (__ninp_ == __einp_)
189            return uflow();
190        return traits_type::to_int_type(*__ninp_++);
191    }
192
193    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
194    int_type sgetc() {
195        if (__ninp_ == __einp_)
196            return underflow();
197        return traits_type::to_int_type(*__ninp_);
198    }
199
200    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
201    streamsize sgetn(char_type* __s, streamsize __n)
202    { return xsgetn(__s, __n); }
203
204    // 27.6.2.2.4 Putback:
205    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
206    int_type sputbackc(char_type __c) {
207        if (__binp_ == __ninp_ || !traits_type::eq(__c, __ninp_[-1]))
208            return pbackfail(traits_type::to_int_type(__c));
209        return traits_type::to_int_type(*--__ninp_);
210    }
211
212    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
213    int_type sungetc() {
214        if (__binp_ == __ninp_)
215          return pbackfail();
216        return traits_type::to_int_type(*--__ninp_);
217    }
218
219    // 27.6.2.2.5 Put area:
220    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
221    int_type sputc(char_type __c) {
222        if (__nout_ == __eout_)
223            return overflow(traits_type::to_int_type(__c));
224        *__nout_++ = __c;
225        return traits_type::to_int_type(__c);
226    }
227
228    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
229    streamsize sputn(const char_type* __s, streamsize __n)
230    { return xsputn(__s, __n); }
231
232protected:
233    basic_streambuf();
234    basic_streambuf(const basic_streambuf& __rhs);
235    basic_streambuf& operator=(const basic_streambuf& __rhs);
236    void swap(basic_streambuf& __rhs);
237
238    // 27.6.2.3.2 Get area:
239    _LIBCPP_INLINE_VISIBILITY char_type* eback() const {return __binp_;}
240    _LIBCPP_INLINE_VISIBILITY char_type* gptr()  const {return __ninp_;}
241    _LIBCPP_INLINE_VISIBILITY char_type* egptr() const {return __einp_;}
242
243    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
244    void gbump(int __n) { __ninp_ += __n; }
245
246    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
247    void setg(char_type* __gbeg, char_type* __gnext, char_type* __gend) {
248        __binp_ = __gbeg;
249        __ninp_ = __gnext;
250        __einp_ = __gend;
251    }
252
253    // 27.6.2.3.3 Put area:
254    _LIBCPP_INLINE_VISIBILITY char_type* pbase() const {return __bout_;}
255    _LIBCPP_INLINE_VISIBILITY char_type* pptr()  const {return __nout_;}
256    _LIBCPP_INLINE_VISIBILITY char_type* epptr() const {return __eout_;}
257
258    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
259    void pbump(int __n) { __nout_ += __n; }
260
261    _LIBCPP_INLINE_VISIBILITY
262    void __pbump(streamsize __n) { __nout_ += __n; }
263
264    inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1
265    void setp(char_type* __pbeg, char_type* __pend) {
266        __bout_ = __nout_ = __pbeg;
267        __eout_ = __pend;
268    }
269
270    // 27.6.2.4 virtual functions:
271    // 27.6.2.4.1 Locales:
272    virtual void imbue(const locale& __loc);
273
274    // 27.6.2.4.2 Buffer management and positioning:
275    virtual basic_streambuf* setbuf(char_type* __s, streamsize __n);
276    virtual pos_type seekoff(off_type __off, ios_base::seekdir __way,
277                             ios_base::openmode __which = ios_base::in | ios_base::out);
278    virtual pos_type seekpos(pos_type __sp,
279                             ios_base::openmode __which = ios_base::in | ios_base::out);
280    virtual int sync();
281
282    // 27.6.2.4.3 Get area:
283    virtual streamsize showmanyc();
284    virtual streamsize xsgetn(char_type* __s, streamsize __n);
285    virtual int_type underflow();
286    virtual int_type uflow();
287
288    // 27.6.2.4.4 Putback:
289    virtual int_type pbackfail(int_type __c = traits_type::eof());
290
291    // 27.6.2.4.5 Put area:
292    virtual streamsize xsputn(const char_type* __s, streamsize __n);
293    virtual int_type overflow(int_type __c = traits_type::eof());
294
295private:
296    locale __loc_;
297    char_type* __binp_;
298    char_type* __ninp_;
299    char_type* __einp_;
300    char_type* __bout_;
301    char_type* __nout_;
302    char_type* __eout_;
303};
304
305template <class _CharT, class _Traits>
306basic_streambuf<_CharT, _Traits>::~basic_streambuf()
307{
308}
309
310template <class _CharT, class _Traits>
311basic_streambuf<_CharT, _Traits>::basic_streambuf()
312    : __binp_(nullptr),
313      __ninp_(nullptr),
314      __einp_(nullptr),
315      __bout_(nullptr),
316      __nout_(nullptr),
317      __eout_(nullptr)
318{
319}
320
321template <class _CharT, class _Traits>
322basic_streambuf<_CharT, _Traits>::basic_streambuf(const basic_streambuf& __sb)
323    : __loc_(__sb.__loc_),
324      __binp_(__sb.__binp_),
325      __ninp_(__sb.__ninp_),
326      __einp_(__sb.__einp_),
327      __bout_(__sb.__bout_),
328      __nout_(__sb.__nout_),
329      __eout_(__sb.__eout_)
330{
331}
332
333template <class _CharT, class _Traits>
334basic_streambuf<_CharT, _Traits>&
335basic_streambuf<_CharT, _Traits>::operator=(const basic_streambuf& __sb)
336{
337    __loc_ = __sb.__loc_;
338    __binp_ = __sb.__binp_;
339    __ninp_ = __sb.__ninp_;
340    __einp_ = __sb.__einp_;
341    __bout_ = __sb.__bout_;
342    __nout_ = __sb.__nout_;
343    __eout_ = __sb.__eout_;
344    return *this;
345}
346
347template <class _CharT, class _Traits>
348void
349basic_streambuf<_CharT, _Traits>::swap(basic_streambuf& __sb)
350{
351    _VSTD::swap(__loc_, __sb.__loc_);
352    _VSTD::swap(__binp_, __sb.__binp_);
353    _VSTD::swap(__ninp_, __sb.__ninp_);
354    _VSTD::swap(__einp_, __sb.__einp_);
355    _VSTD::swap(__bout_, __sb.__bout_);
356    _VSTD::swap(__nout_, __sb.__nout_);
357    _VSTD::swap(__eout_, __sb.__eout_);
358}
359
360template <class _CharT, class _Traits>
361void
362basic_streambuf<_CharT, _Traits>::imbue(const locale&)
363{
364}
365
366template <class _CharT, class _Traits>
367basic_streambuf<_CharT, _Traits>*
368basic_streambuf<_CharT, _Traits>::setbuf(char_type*, streamsize)
369{
370    return this;
371}
372
373template <class _CharT, class _Traits>
374typename basic_streambuf<_CharT, _Traits>::pos_type
375basic_streambuf<_CharT, _Traits>::seekoff(off_type, ios_base::seekdir,
376                                          ios_base::openmode)
377{
378    return pos_type(off_type(-1));
379}
380
381template <class _CharT, class _Traits>
382typename basic_streambuf<_CharT, _Traits>::pos_type
383basic_streambuf<_CharT, _Traits>::seekpos(pos_type, ios_base::openmode)
384{
385    return pos_type(off_type(-1));
386}
387
388template <class _CharT, class _Traits>
389int
390basic_streambuf<_CharT, _Traits>::sync()
391{
392    return 0;
393}
394
395template <class _CharT, class _Traits>
396streamsize
397basic_streambuf<_CharT, _Traits>::showmanyc()
398{
399    return 0;
400}
401
402template <class _CharT, class _Traits>
403streamsize
404basic_streambuf<_CharT, _Traits>::xsgetn(char_type* __s, streamsize __n)
405{
406    const int_type __eof = traits_type::eof();
407    int_type __c;
408    streamsize __i = 0;
409    while(__i < __n)
410    {
411        if (__ninp_ < __einp_)
412        {
413            const streamsize __len = _VSTD::min(static_cast<streamsize>(INT_MAX),
414                                _VSTD::min(__einp_ - __ninp_, __n - __i));
415            traits_type::copy(__s, __ninp_, __len);
416            __s +=  __len;
417            __i +=  __len;
418            this->gbump(__len);
419        }
420        else if ((__c = uflow()) != __eof)
421        {
422            *__s = traits_type::to_char_type(__c);
423            ++__s;
424            ++__i;
425        }
426        else
427            break;
428    }
429    return __i;
430}
431
432template <class _CharT, class _Traits>
433typename basic_streambuf<_CharT, _Traits>::int_type
434basic_streambuf<_CharT, _Traits>::underflow()
435{
436    return traits_type::eof();
437}
438
439template <class _CharT, class _Traits>
440typename basic_streambuf<_CharT, _Traits>::int_type
441basic_streambuf<_CharT, _Traits>::uflow()
442{
443    if (underflow() == traits_type::eof())
444        return traits_type::eof();
445    return traits_type::to_int_type(*__ninp_++);
446}
447
448template <class _CharT, class _Traits>
449typename basic_streambuf<_CharT, _Traits>::int_type
450basic_streambuf<_CharT, _Traits>::pbackfail(int_type)
451{
452    return traits_type::eof();
453}
454
455template <class _CharT, class _Traits>
456streamsize
457basic_streambuf<_CharT, _Traits>::xsputn(const char_type* __s, streamsize __n)
458{
459    streamsize __i = 0;
460    int_type __eof = traits_type::eof();
461    while( __i < __n)
462    {
463        if (__nout_ >= __eout_)
464        {
465            if (overflow(traits_type::to_int_type(*__s)) == __eof)
466                break;
467            ++__s;
468            ++__i;
469        }
470        else
471        {
472            streamsize __chunk_size = _VSTD::min(__eout_ - __nout_, __n - __i);
473            traits_type::copy(__nout_, __s, __chunk_size);
474            __nout_ += __chunk_size;
475            __s     += __chunk_size;
476            __i     += __chunk_size;
477        }
478    }
479    return __i;
480}
481
482template <class _CharT, class _Traits>
483typename basic_streambuf<_CharT, _Traits>::int_type
484basic_streambuf<_CharT, _Traits>::overflow(int_type)
485{
486    return traits_type::eof();
487}
488
489_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<char>)
490_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<wchar_t>)
491
492_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ios<char>)
493_LIBCPP_EXTERN_TEMPLATE(class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_ios<wchar_t>)
494
495_LIBCPP_END_NAMESPACE_STD
496
497_LIBCPP_POP_MACROS
498
499#endif // _LIBCPP_STREAMBUF
500