xref: /freebsd/contrib/llvm-project/libcxx/include/streambuf (revision 3750ccefb8629a08890bfbae894dd6bc6a7483b4)
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 <__assert>
111#include <__config>
112#include <__fwd/streambuf.h>
113#include <__locale>
114#include <__type_traits/is_same.h>
115#include <__utility/is_valid_range.h>
116#include <climits>
117#include <ios>
118#include <iosfwd>
119#include <version>
120
121#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
122#  pragma GCC system_header
123#endif
124
125_LIBCPP_PUSH_MACROS
126#include <__undef_macros>
127
128_LIBCPP_BEGIN_NAMESPACE_STD
129
130template <class _CharT, class _Traits>
131class _LIBCPP_TEMPLATE_VIS basic_streambuf {
132public:
133  // types:
134  typedef _CharT char_type;
135  typedef _Traits traits_type;
136  typedef typename traits_type::int_type int_type;
137  typedef typename traits_type::pos_type pos_type;
138  typedef typename traits_type::off_type off_type;
139
140  static_assert(is_same<_CharT, typename traits_type::char_type>::value,
141                "traits_type::char_type must be the same type as CharT");
142
143  virtual ~basic_streambuf();
144
145  // 27.6.2.2.1 locales:
146  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale pubimbue(const locale& __loc) {
147    imbue(__loc);
148    locale __r = __loc_;
149    __loc_     = __loc;
150    return __r;
151  }
152
153  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale getloc() const { return __loc_; }
154
155  // 27.6.2.2.2 buffer and positioning:
156  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_streambuf* pubsetbuf(char_type* __s, streamsize __n) {
157    return setbuf(__s, __n);
158  }
159
160  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
161  pubseekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out) {
162    return seekoff(__off, __way, __which);
163  }
164
165  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
166  pubseekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out) {
167    return seekpos(__sp, __which);
168  }
169
170  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int pubsync() { return sync(); }
171
172  // Get and put areas:
173  // 27.6.2.2.3 Get area:
174  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize in_avail() {
175    if (__ninp_ < __einp_)
176      return static_cast<streamsize>(__einp_ - __ninp_);
177    return showmanyc();
178  }
179
180  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 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 int_type sbumpc() {
187    if (__ninp_ == __einp_)
188      return uflow();
189    return traits_type::to_int_type(*__ninp_++);
190  }
191
192  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sgetc() {
193    if (__ninp_ == __einp_)
194      return underflow();
195    return traits_type::to_int_type(*__ninp_);
196  }
197
198  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sgetn(char_type* __s, streamsize __n) { return xsgetn(__s, __n); }
199
200  // 27.6.2.2.4 Putback:
201  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputbackc(char_type __c) {
202    if (__binp_ == __ninp_ || !traits_type::eq(__c, __ninp_[-1]))
203      return pbackfail(traits_type::to_int_type(__c));
204    return traits_type::to_int_type(*--__ninp_);
205  }
206
207  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sungetc() {
208    if (__binp_ == __ninp_)
209      return pbackfail();
210    return traits_type::to_int_type(*--__ninp_);
211  }
212
213  // 27.6.2.2.5 Put area:
214  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputc(char_type __c) {
215    if (__nout_ == __eout_)
216      return overflow(traits_type::to_int_type(__c));
217    *__nout_++ = __c;
218    return traits_type::to_int_type(__c);
219  }
220
221  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sputn(const char_type* __s, streamsize __n) {
222    return xsputn(__s, __n);
223  }
224
225protected:
226  basic_streambuf();
227  basic_streambuf(const basic_streambuf& __rhs);
228  basic_streambuf& operator=(const basic_streambuf& __rhs);
229  void swap(basic_streambuf& __rhs);
230
231  // 27.6.2.3.2 Get area:
232  _LIBCPP_HIDE_FROM_ABI char_type* eback() const { return __binp_; }
233  _LIBCPP_HIDE_FROM_ABI char_type* gptr() const { return __ninp_; }
234  _LIBCPP_HIDE_FROM_ABI char_type* egptr() const { return __einp_; }
235
236  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void gbump(int __n) { __ninp_ += __n; }
237
238  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setg(char_type* __gbeg, char_type* __gnext, char_type* __gend) {
239    _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gbeg, __gnext), "[gbeg, gnext) must be a valid range");
240    _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gbeg, __gend), "[gbeg, gend) must be a valid range");
241    _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__gnext, __gend), "[gnext, gend) must be a valid range");
242    __binp_ = __gbeg;
243    __ninp_ = __gnext;
244    __einp_ = __gend;
245  }
246
247  // 27.6.2.3.3 Put area:
248  _LIBCPP_HIDE_FROM_ABI char_type* pbase() const { return __bout_; }
249  _LIBCPP_HIDE_FROM_ABI char_type* pptr() const { return __nout_; }
250  _LIBCPP_HIDE_FROM_ABI char_type* epptr() const { return __eout_; }
251
252  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void pbump(int __n) { __nout_ += __n; }
253
254  _LIBCPP_HIDE_FROM_ABI void __pbump(streamsize __n) { __nout_ += __n; }
255
256  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setp(char_type* __pbeg, char_type* __pend) {
257    _LIBCPP_ASSERT_VALID_INPUT_RANGE(std::__is_valid_range(__pbeg, __pend), "[pbeg, pend) must be a valid range");
258    __bout_ = __nout_ = __pbeg;
259    __eout_           = __pend;
260  }
261
262  // 27.6.2.4 virtual functions:
263  // 27.6.2.4.1 Locales:
264  virtual void imbue(const locale& __loc);
265
266  // 27.6.2.4.2 Buffer management and positioning:
267  virtual basic_streambuf* setbuf(char_type* __s, streamsize __n);
268  virtual pos_type
269  seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out);
270  virtual pos_type seekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out);
271  virtual int sync();
272
273  // 27.6.2.4.3 Get area:
274  virtual streamsize showmanyc();
275  virtual streamsize xsgetn(char_type* __s, streamsize __n);
276  virtual int_type underflow();
277  virtual int_type uflow();
278
279  // 27.6.2.4.4 Putback:
280  virtual int_type pbackfail(int_type __c = traits_type::eof());
281
282  // 27.6.2.4.5 Put area:
283  virtual streamsize xsputn(const char_type* __s, streamsize __n);
284  virtual int_type overflow(int_type __c = traits_type::eof());
285
286private:
287  locale __loc_;
288  char_type* __binp_;
289  char_type* __ninp_;
290  char_type* __einp_;
291  char_type* __bout_;
292  char_type* __nout_;
293  char_type* __eout_;
294};
295
296template <class _CharT, class _Traits>
297basic_streambuf<_CharT, _Traits>::~basic_streambuf() {}
298
299template <class _CharT, class _Traits>
300basic_streambuf<_CharT, _Traits>::basic_streambuf()
301    : __binp_(nullptr), __ninp_(nullptr), __einp_(nullptr), __bout_(nullptr), __nout_(nullptr), __eout_(nullptr) {}
302
303template <class _CharT, class _Traits>
304basic_streambuf<_CharT, _Traits>::basic_streambuf(const basic_streambuf& __sb)
305    : __loc_(__sb.__loc_),
306      __binp_(__sb.__binp_),
307      __ninp_(__sb.__ninp_),
308      __einp_(__sb.__einp_),
309      __bout_(__sb.__bout_),
310      __nout_(__sb.__nout_),
311      __eout_(__sb.__eout_) {}
312
313template <class _CharT, class _Traits>
314basic_streambuf<_CharT, _Traits>& basic_streambuf<_CharT, _Traits>::operator=(const basic_streambuf& __sb) {
315  __loc_  = __sb.__loc_;
316  __binp_ = __sb.__binp_;
317  __ninp_ = __sb.__ninp_;
318  __einp_ = __sb.__einp_;
319  __bout_ = __sb.__bout_;
320  __nout_ = __sb.__nout_;
321  __eout_ = __sb.__eout_;
322  return *this;
323}
324
325template <class _CharT, class _Traits>
326void basic_streambuf<_CharT, _Traits>::swap(basic_streambuf& __sb) {
327  std::swap(__loc_, __sb.__loc_);
328  std::swap(__binp_, __sb.__binp_);
329  std::swap(__ninp_, __sb.__ninp_);
330  std::swap(__einp_, __sb.__einp_);
331  std::swap(__bout_, __sb.__bout_);
332  std::swap(__nout_, __sb.__nout_);
333  std::swap(__eout_, __sb.__eout_);
334}
335
336template <class _CharT, class _Traits>
337void basic_streambuf<_CharT, _Traits>::imbue(const locale&) {}
338
339template <class _CharT, class _Traits>
340basic_streambuf<_CharT, _Traits>* basic_streambuf<_CharT, _Traits>::setbuf(char_type*, streamsize) {
341  return this;
342}
343
344template <class _CharT, class _Traits>
345typename basic_streambuf<_CharT, _Traits>::pos_type
346basic_streambuf<_CharT, _Traits>::seekoff(off_type, ios_base::seekdir, ios_base::openmode) {
347  return pos_type(off_type(-1));
348}
349
350template <class _CharT, class _Traits>
351typename basic_streambuf<_CharT, _Traits>::pos_type
352basic_streambuf<_CharT, _Traits>::seekpos(pos_type, ios_base::openmode) {
353  return pos_type(off_type(-1));
354}
355
356template <class _CharT, class _Traits>
357int basic_streambuf<_CharT, _Traits>::sync() {
358  return 0;
359}
360
361template <class _CharT, class _Traits>
362streamsize basic_streambuf<_CharT, _Traits>::showmanyc() {
363  return 0;
364}
365
366template <class _CharT, class _Traits>
367streamsize basic_streambuf<_CharT, _Traits>::xsgetn(char_type* __s, streamsize __n) {
368  const int_type __eof = traits_type::eof();
369  int_type __c;
370  streamsize __i = 0;
371  while (__i < __n) {
372    if (__ninp_ < __einp_) {
373      const streamsize __len = std::min(static_cast<streamsize>(INT_MAX), std::min(__einp_ - __ninp_, __n - __i));
374      traits_type::copy(__s, __ninp_, __len);
375      __s += __len;
376      __i += __len;
377      this->gbump(__len);
378    } else if ((__c = uflow()) != __eof) {
379      *__s = traits_type::to_char_type(__c);
380      ++__s;
381      ++__i;
382    } else
383      break;
384  }
385  return __i;
386}
387
388template <class _CharT, class _Traits>
389typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::underflow() {
390  return traits_type::eof();
391}
392
393template <class _CharT, class _Traits>
394typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::uflow() {
395  if (underflow() == traits_type::eof())
396    return traits_type::eof();
397  return traits_type::to_int_type(*__ninp_++);
398}
399
400template <class _CharT, class _Traits>
401typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::pbackfail(int_type) {
402  return traits_type::eof();
403}
404
405template <class _CharT, class _Traits>
406streamsize basic_streambuf<_CharT, _Traits>::xsputn(const char_type* __s, streamsize __n) {
407  streamsize __i = 0;
408  int_type __eof = traits_type::eof();
409  while (__i < __n) {
410    if (__nout_ >= __eout_) {
411      if (overflow(traits_type::to_int_type(*__s)) == __eof)
412        break;
413      ++__s;
414      ++__i;
415    } else {
416      streamsize __chunk_size = std::min(__eout_ - __nout_, __n - __i);
417      traits_type::copy(__nout_, __s, __chunk_size);
418      __nout_ += __chunk_size;
419      __s += __chunk_size;
420      __i += __chunk_size;
421    }
422  }
423  return __i;
424}
425
426template <class _CharT, class _Traits>
427typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::overflow(int_type) {
428  return traits_type::eof();
429}
430
431extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<char>;
432
433#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
434extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<wchar_t>;
435#endif
436
437_LIBCPP_END_NAMESPACE_STD
438
439_LIBCPP_POP_MACROS
440
441#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
442#  include <cstdint>
443#endif
444
445#endif // _LIBCPP_STREAMBUF
446