xref: /freebsd/contrib/llvm-project/libcxx/include/streambuf (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
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> // all public C++ headers provide the assertion handler
111#include <__config>
112#include <__fwd/streambuf.h>
113#include <climits>
114#include <ios>
115#include <iosfwd>
116#include <version>
117
118#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
119#  pragma GCC system_header
120#endif
121
122_LIBCPP_PUSH_MACROS
123#include <__undef_macros>
124
125_LIBCPP_BEGIN_NAMESPACE_STD
126
127template <class _CharT, class _Traits>
128class _LIBCPP_TEMPLATE_VIS basic_streambuf {
129public:
130  // types:
131  typedef _CharT char_type;
132  typedef _Traits traits_type;
133  typedef typename traits_type::int_type int_type;
134  typedef typename traits_type::pos_type pos_type;
135  typedef typename traits_type::off_type off_type;
136
137  static_assert((is_same<_CharT, typename traits_type::char_type>::value),
138                "traits_type::char_type must be the same type as CharT");
139
140  virtual ~basic_streambuf();
141
142  // 27.6.2.2.1 locales:
143  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale pubimbue(const locale& __loc) {
144    imbue(__loc);
145    locale __r = __loc_;
146    __loc_     = __loc;
147    return __r;
148  }
149
150  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 locale getloc() const { return __loc_; }
151
152  // 27.6.2.2.2 buffer and positioning:
153  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 basic_streambuf* pubsetbuf(char_type* __s, streamsize __n) {
154    return setbuf(__s, __n);
155  }
156
157  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
158  pubseekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out) {
159    return seekoff(__off, __way, __which);
160  }
161
162  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 pos_type
163  pubseekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out) {
164    return seekpos(__sp, __which);
165  }
166
167  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int pubsync() { return sync(); }
168
169  // Get and put areas:
170  // 27.6.2.2.3 Get area:
171  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize in_avail() {
172    if (__ninp_ < __einp_)
173      return static_cast<streamsize>(__einp_ - __ninp_);
174    return showmanyc();
175  }
176
177  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type snextc() {
178    if (sbumpc() == traits_type::eof())
179      return traits_type::eof();
180    return sgetc();
181  }
182
183  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sbumpc() {
184    if (__ninp_ == __einp_)
185      return uflow();
186    return traits_type::to_int_type(*__ninp_++);
187  }
188
189  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sgetc() {
190    if (__ninp_ == __einp_)
191      return underflow();
192    return traits_type::to_int_type(*__ninp_);
193  }
194
195  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sgetn(char_type* __s, streamsize __n) { return xsgetn(__s, __n); }
196
197  // 27.6.2.2.4 Putback:
198  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputbackc(char_type __c) {
199    if (__binp_ == __ninp_ || !traits_type::eq(__c, __ninp_[-1]))
200      return pbackfail(traits_type::to_int_type(__c));
201    return traits_type::to_int_type(*--__ninp_);
202  }
203
204  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sungetc() {
205    if (__binp_ == __ninp_)
206      return pbackfail();
207    return traits_type::to_int_type(*--__ninp_);
208  }
209
210  // 27.6.2.2.5 Put area:
211  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 int_type sputc(char_type __c) {
212    if (__nout_ == __eout_)
213      return overflow(traits_type::to_int_type(__c));
214    *__nout_++ = __c;
215    return traits_type::to_int_type(__c);
216  }
217
218  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 streamsize sputn(const char_type* __s, streamsize __n) {
219    return xsputn(__s, __n);
220  }
221
222protected:
223  basic_streambuf();
224  basic_streambuf(const basic_streambuf& __rhs);
225  basic_streambuf& operator=(const basic_streambuf& __rhs);
226  void swap(basic_streambuf& __rhs);
227
228  // 27.6.2.3.2 Get area:
229  _LIBCPP_HIDE_FROM_ABI char_type* eback() const { return __binp_; }
230  _LIBCPP_HIDE_FROM_ABI char_type* gptr() const { return __ninp_; }
231  _LIBCPP_HIDE_FROM_ABI char_type* egptr() const { return __einp_; }
232
233  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void gbump(int __n) { __ninp_ += __n; }
234
235  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setg(char_type* __gbeg, char_type* __gnext, char_type* __gend) {
236    __binp_ = __gbeg;
237    __ninp_ = __gnext;
238    __einp_ = __gend;
239  }
240
241  // 27.6.2.3.3 Put area:
242  _LIBCPP_HIDE_FROM_ABI char_type* pbase() const { return __bout_; }
243  _LIBCPP_HIDE_FROM_ABI char_type* pptr() const { return __nout_; }
244  _LIBCPP_HIDE_FROM_ABI char_type* epptr() const { return __eout_; }
245
246  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void pbump(int __n) { __nout_ += __n; }
247
248  _LIBCPP_HIDE_FROM_ABI void __pbump(streamsize __n) { __nout_ += __n; }
249
250  inline _LIBCPP_HIDE_FROM_ABI_AFTER_V1 void setp(char_type* __pbeg, char_type* __pend) {
251    __bout_ = __nout_ = __pbeg;
252    __eout_           = __pend;
253  }
254
255  // 27.6.2.4 virtual functions:
256  // 27.6.2.4.1 Locales:
257  virtual void imbue(const locale& __loc);
258
259  // 27.6.2.4.2 Buffer management and positioning:
260  virtual basic_streambuf* setbuf(char_type* __s, streamsize __n);
261  virtual pos_type
262  seekoff(off_type __off, ios_base::seekdir __way, ios_base::openmode __which = ios_base::in | ios_base::out);
263  virtual pos_type seekpos(pos_type __sp, ios_base::openmode __which = ios_base::in | ios_base::out);
264  virtual int sync();
265
266  // 27.6.2.4.3 Get area:
267  virtual streamsize showmanyc();
268  virtual streamsize xsgetn(char_type* __s, streamsize __n);
269  virtual int_type underflow();
270  virtual int_type uflow();
271
272  // 27.6.2.4.4 Putback:
273  virtual int_type pbackfail(int_type __c = traits_type::eof());
274
275  // 27.6.2.4.5 Put area:
276  virtual streamsize xsputn(const char_type* __s, streamsize __n);
277  virtual int_type overflow(int_type __c = traits_type::eof());
278
279private:
280  locale __loc_;
281  char_type* __binp_;
282  char_type* __ninp_;
283  char_type* __einp_;
284  char_type* __bout_;
285  char_type* __nout_;
286  char_type* __eout_;
287};
288
289template <class _CharT, class _Traits>
290basic_streambuf<_CharT, _Traits>::~basic_streambuf() {}
291
292template <class _CharT, class _Traits>
293basic_streambuf<_CharT, _Traits>::basic_streambuf()
294    : __binp_(nullptr), __ninp_(nullptr), __einp_(nullptr), __bout_(nullptr), __nout_(nullptr), __eout_(nullptr) {}
295
296template <class _CharT, class _Traits>
297basic_streambuf<_CharT, _Traits>::basic_streambuf(const basic_streambuf& __sb)
298    : __loc_(__sb.__loc_),
299      __binp_(__sb.__binp_),
300      __ninp_(__sb.__ninp_),
301      __einp_(__sb.__einp_),
302      __bout_(__sb.__bout_),
303      __nout_(__sb.__nout_),
304      __eout_(__sb.__eout_) {}
305
306template <class _CharT, class _Traits>
307basic_streambuf<_CharT, _Traits>& basic_streambuf<_CharT, _Traits>::operator=(const basic_streambuf& __sb) {
308  __loc_  = __sb.__loc_;
309  __binp_ = __sb.__binp_;
310  __ninp_ = __sb.__ninp_;
311  __einp_ = __sb.__einp_;
312  __bout_ = __sb.__bout_;
313  __nout_ = __sb.__nout_;
314  __eout_ = __sb.__eout_;
315  return *this;
316}
317
318template <class _CharT, class _Traits>
319void basic_streambuf<_CharT, _Traits>::swap(basic_streambuf& __sb) {
320  std::swap(__loc_, __sb.__loc_);
321  std::swap(__binp_, __sb.__binp_);
322  std::swap(__ninp_, __sb.__ninp_);
323  std::swap(__einp_, __sb.__einp_);
324  std::swap(__bout_, __sb.__bout_);
325  std::swap(__nout_, __sb.__nout_);
326  std::swap(__eout_, __sb.__eout_);
327}
328
329template <class _CharT, class _Traits>
330void basic_streambuf<_CharT, _Traits>::imbue(const locale&) {}
331
332template <class _CharT, class _Traits>
333basic_streambuf<_CharT, _Traits>* basic_streambuf<_CharT, _Traits>::setbuf(char_type*, streamsize) {
334  return this;
335}
336
337template <class _CharT, class _Traits>
338typename basic_streambuf<_CharT, _Traits>::pos_type
339basic_streambuf<_CharT, _Traits>::seekoff(off_type, ios_base::seekdir, ios_base::openmode) {
340  return pos_type(off_type(-1));
341}
342
343template <class _CharT, class _Traits>
344typename basic_streambuf<_CharT, _Traits>::pos_type
345basic_streambuf<_CharT, _Traits>::seekpos(pos_type, ios_base::openmode) {
346  return pos_type(off_type(-1));
347}
348
349template <class _CharT, class _Traits>
350int basic_streambuf<_CharT, _Traits>::sync() {
351  return 0;
352}
353
354template <class _CharT, class _Traits>
355streamsize basic_streambuf<_CharT, _Traits>::showmanyc() {
356  return 0;
357}
358
359template <class _CharT, class _Traits>
360streamsize basic_streambuf<_CharT, _Traits>::xsgetn(char_type* __s, streamsize __n) {
361  const int_type __eof = traits_type::eof();
362  int_type __c;
363  streamsize __i = 0;
364  while (__i < __n) {
365    if (__ninp_ < __einp_) {
366      const streamsize __len = std::min(static_cast<streamsize>(INT_MAX), std::min(__einp_ - __ninp_, __n - __i));
367      traits_type::copy(__s, __ninp_, __len);
368      __s += __len;
369      __i += __len;
370      this->gbump(__len);
371    } else if ((__c = uflow()) != __eof) {
372      *__s = traits_type::to_char_type(__c);
373      ++__s;
374      ++__i;
375    } else
376      break;
377  }
378  return __i;
379}
380
381template <class _CharT, class _Traits>
382typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::underflow() {
383  return traits_type::eof();
384}
385
386template <class _CharT, class _Traits>
387typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::uflow() {
388  if (underflow() == traits_type::eof())
389    return traits_type::eof();
390  return traits_type::to_int_type(*__ninp_++);
391}
392
393template <class _CharT, class _Traits>
394typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::pbackfail(int_type) {
395  return traits_type::eof();
396}
397
398template <class _CharT, class _Traits>
399streamsize basic_streambuf<_CharT, _Traits>::xsputn(const char_type* __s, streamsize __n) {
400  streamsize __i = 0;
401  int_type __eof = traits_type::eof();
402  while (__i < __n) {
403    if (__nout_ >= __eout_) {
404      if (overflow(traits_type::to_int_type(*__s)) == __eof)
405        break;
406      ++__s;
407      ++__i;
408    } else {
409      streamsize __chunk_size = std::min(__eout_ - __nout_, __n - __i);
410      traits_type::copy(__nout_, __s, __chunk_size);
411      __nout_ += __chunk_size;
412      __s += __chunk_size;
413      __i += __chunk_size;
414    }
415  }
416  return __i;
417}
418
419template <class _CharT, class _Traits>
420typename basic_streambuf<_CharT, _Traits>::int_type basic_streambuf<_CharT, _Traits>::overflow(int_type) {
421  return traits_type::eof();
422}
423
424extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<char>;
425
426#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
427extern template class _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS basic_streambuf<wchar_t>;
428#endif
429
430_LIBCPP_END_NAMESPACE_STD
431
432_LIBCPP_POP_MACROS
433
434#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
435#  include <cstdint>
436#endif
437
438#endif // _LIBCPP_STREAMBUF
439