1// strstream definitions -*- C++ -*-
2
3// Copyright (C) 2001-2015 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// <http://www.gnu.org/licenses/>.
24
25/*
26 * Copyright (c) 1998
27 * Silicon Graphics Computer Systems, Inc.
28 *
29 * Permission to use, copy, modify, distribute and sell this software
30 * and its documentation for any purpose is hereby granted without fee,
31 * provided that the above copyright notice appear in all copies and
32 * that both that copyright notice and this permission notice appear
33 * in supporting documentation.  Silicon Graphics makes no
34 * representations about the suitability of this software for any
35 * purpose.  It is provided "as is" without express or implied warranty.
36 */
37
38// Implementation of the classes in header <strstream>.
39// WARNING: The classes defined in <strstream> are DEPRECATED.  This
40// header is defined in section D.7.1 of the C++ standard, and it
41// MAY BE REMOVED in a future standard revision.  You should use the
42// header <sstream> instead.
43
44#include <strstream>
45#include <algorithm>
46#include <new>
47#include <stdlib.h>
48#include <string.h>
49#include <limits.h>
50
51namespace std _GLIBCXX_VISIBILITY(default)
52{
53_GLIBCXX_BEGIN_NAMESPACE_VERSION
54
55  strstreambuf::strstreambuf(streamsize initial_capacity)
56  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(true),
57    _M_frozen(false), _M_constant(false)
58  {
59    streamsize n = std::max(initial_capacity, streamsize(16));
60
61    char* buf = _M_alloc(n);
62    if (buf)
63      {
64	setp(buf, buf + n);
65	setg(buf, buf, buf);
66      }
67  }
68
69  strstreambuf::strstreambuf(void* (*alloc_f)(size_t), void (*free_f)(void*))
70  : _Base(), _M_alloc_fun(alloc_f), _M_free_fun(free_f), _M_dynamic(true),
71    _M_frozen(false), _M_constant(false)
72  {
73    streamsize n = 16;
74
75    char* buf = _M_alloc(n);
76    if (buf)
77      {
78	setp(buf, buf + n);
79	setg(buf, buf, buf);
80      }
81  }
82
83  strstreambuf::strstreambuf(char* get, streamsize n, char* put) throw ()
84  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
85    _M_frozen(false), _M_constant(false)
86  { _M_setup(get, put, n); }
87
88  strstreambuf::strstreambuf(signed char* get, streamsize n, signed char* put) throw ()
89  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
90  _M_frozen(false), _M_constant(false)
91  { _M_setup(reinterpret_cast<char*>(get), reinterpret_cast<char*>(put), n); }
92
93  strstreambuf::strstreambuf(unsigned char* get, streamsize n,
94			     unsigned char* put) throw ()
95  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
96    _M_frozen(false), _M_constant(false)
97  { _M_setup(reinterpret_cast<char*>(get), reinterpret_cast<char*>(put), n); }
98
99  strstreambuf::strstreambuf(const char* get, streamsize n) throw ()
100  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
101    _M_frozen(false), _M_constant(true)
102  { _M_setup(const_cast<char*>(get), 0, n); }
103
104  strstreambuf::strstreambuf(const signed char* get, streamsize n) throw ()
105  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
106    _M_frozen(false), _M_constant(true)
107  { _M_setup(reinterpret_cast<char*>(const_cast<signed char*>(get)), 0, n); }
108
109  strstreambuf::strstreambuf(const unsigned char* get, streamsize n) throw ()
110  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
111    _M_frozen(false), _M_constant(true)
112  { _M_setup(reinterpret_cast<char*>(const_cast<unsigned char*>(get)), 0, n); }
113
114  strstreambuf::~strstreambuf()
115  {
116    if (_M_dynamic && !_M_frozen)
117      _M_free(eback());
118  }
119
120  void
121  strstreambuf::freeze(bool frozenflag) throw ()
122  {
123    if (_M_dynamic)
124      _M_frozen = frozenflag;
125  }
126
127  char*
128  strstreambuf::str() throw ()
129  {
130    freeze(true);
131    return eback();
132  }
133
134  int
135  strstreambuf::pcount() const throw ()
136  { return pptr() ? pptr() - pbase() : 0; }
137
138  strstreambuf::int_type
139  strstreambuf::overflow(int_type c)
140  {
141    if (c == traits_type::eof())
142      return traits_type::not_eof(c);
143
144    // Try to expand the buffer.
145    if (pptr() == epptr() && _M_dynamic && !_M_frozen && !_M_constant)
146      {
147	ptrdiff_t old_size = epptr() - pbase();
148	ptrdiff_t new_size = std::max(ptrdiff_t(2 * old_size), ptrdiff_t(1));
149
150	char* buf = _M_alloc(new_size);
151	if (buf)
152	  {
153	    memcpy(buf, pbase(), old_size);
154	    char* old_buffer = pbase();
155	    bool reposition_get = false;
156	    ptrdiff_t old_get_offset;
157	    if (gptr() != 0)
158	      {
159		reposition_get = true;
160		old_get_offset = gptr() - eback();
161	      }
162
163	    setp(buf, buf + new_size);
164	    __safe_pbump(old_size);
165
166	    if (reposition_get)
167	      setg(buf, buf + old_get_offset, buf +
168		   std::max(old_get_offset, old_size));
169
170	    _M_free(old_buffer);
171	  }
172      }
173
174    if (pptr() != epptr())
175      {
176	*pptr() = c;
177	pbump(1);
178	return c;
179      }
180    else
181      return traits_type::eof();
182  }
183
184  strstreambuf::int_type
185  strstreambuf::pbackfail(int_type c)
186  {
187    if (gptr() != eback())
188      {
189      if (c == _Traits::eof())
190	{
191	  gbump(-1);
192	  return _Traits::not_eof(c);
193	}
194      else if (c == _Traits::to_int_type(gptr()[-1]))
195	{  // KLUDGE
196	  gbump(-1);
197	  return c;
198	}
199      else if (!_M_constant)
200	{
201	  gbump(-1);
202	  *gptr() = c;
203	  return c;
204	}
205    }
206    return _Traits::eof();
207  }
208
209  strstreambuf::int_type
210  strstreambuf::underflow()
211  {
212    if (gptr() == egptr() && pptr() && pptr() > egptr())
213      setg(eback(), gptr(), pptr());
214
215    if (gptr() != egptr())
216      return (unsigned char) *gptr();
217    else
218      return _Traits::eof();
219  }
220
221  basic_streambuf<char, char_traits<char> >*
222  strstreambuf::setbuf(char*, streamsize)
223  { return this; }
224
225  strstreambuf::pos_type
226  strstreambuf::seekoff(off_type off, ios_base::seekdir dir,
227			ios_base::openmode mode)
228  {
229    bool do_get = false;
230    bool do_put = false;
231
232    if ((mode & (ios_base::in | ios_base::out))
233	== (ios_base::in | ios_base::out) &&
234	(dir == ios_base::beg || dir == ios_base::end))
235      do_get = do_put = true;
236    else if (mode & ios_base::in)
237      do_get = true;
238    else if (mode & ios_base::out)
239      do_put = true;
240
241    // !gptr() is here because, according to D.7.1 paragraph 4, the seekable
242    // area is undefined if there is no get area.
243    if ((!do_get && !do_put) || (do_put && !pptr()) || !gptr())
244      return pos_type(off_type(-1));
245
246    char* seeklow  = eback();
247    char* seekhigh = epptr() ? epptr() : egptr();
248
249    off_type newoff;
250    switch (dir)
251      {
252      case ios_base::beg:
253	newoff = 0;
254	break;
255      case ios_base::end:
256	newoff = seekhigh - seeklow;
257	break;
258      case ios_base::cur:
259	newoff = do_put ? pptr() - seeklow : gptr() - seeklow;
260	break;
261      default:
262	return pos_type(off_type(-1));
263      }
264
265    off += newoff;
266    if (off < 0 || off > seekhigh - seeklow)
267      return pos_type(off_type(-1));
268
269    if (do_put)
270      {
271	if (seeklow + off < pbase())
272	  {
273	    setp(seeklow, epptr());
274	    __safe_pbump(off);
275	  }
276	else
277	  {
278	    setp(pbase(), epptr());
279	    __safe_pbump(off - (pbase() - seeklow));
280	  }
281      }
282    if (do_get)
283      {
284	if (off <= egptr() - seeklow)
285	  setg(seeklow, seeklow + off, egptr());
286	else if (off <= pptr() - seeklow)
287	  setg(seeklow, seeklow + off, pptr());
288	else
289	  setg(seeklow, seeklow + off, epptr());
290      }
291    return pos_type(newoff);
292  }
293
294  strstreambuf::pos_type
295  strstreambuf::seekpos(pos_type pos, ios_base::openmode mode)
296  { return seekoff(pos - pos_type(off_type(0)), ios_base::beg, mode); }
297
298  char*
299  strstreambuf::_M_alloc(size_t n)
300  {
301    if (_M_alloc_fun)
302      return static_cast<char*>(_M_alloc_fun(n));
303    else
304      return new char[n];
305  }
306
307  void
308  strstreambuf::_M_free(char* p)
309  {
310    if (p)
311      {
312	if (_M_free_fun)
313	  _M_free_fun(p);
314	else
315	  delete[] p;
316      }
317  }
318
319  void
320  strstreambuf::_M_setup(char* get, char* put, streamsize n) throw ()
321  {
322    if (get)
323      {
324	size_t N = n > 0 ? size_t(n) : n == 0 ? strlen(get) : size_t(INT_MAX);
325
326	if (put)
327	  {
328	    setg(get, get, put);
329	    setp(put, put + N);
330	  }
331	else
332	  setg(get, get, get + N);
333      }
334  }
335
336  istrstream::istrstream(char* s)
337  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
338  { basic_ios<char>::init(&_M_buf); }
339
340  istrstream::istrstream(const char* s)
341  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
342  { basic_ios<char>::init(&_M_buf); }
343
344  istrstream::istrstream(char* s, streamsize n)
345  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
346  { basic_ios<char>::init(&_M_buf); }
347
348  istrstream::istrstream(const char* s, streamsize n)
349  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
350  { basic_ios<char>::init(&_M_buf); }
351
352  istrstream::~istrstream() { }
353
354  strstreambuf*
355  istrstream::rdbuf() const throw ()
356  { return const_cast<strstreambuf*>(&_M_buf); }
357
358  char*
359  istrstream::str() throw ()
360  { return _M_buf.str(); }
361
362  ostrstream::ostrstream()
363  : basic_ios<char>(), basic_ostream<char>(0), _M_buf()
364  { basic_ios<char>::init(&_M_buf); }
365
366  ostrstream::ostrstream(char* s, int n, ios_base::openmode mode)
367  : basic_ios<char>(), basic_ostream<char>(0),
368    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
369  { basic_ios<char>::init(&_M_buf); }
370
371  ostrstream::~ostrstream() {}
372
373  strstreambuf*
374  ostrstream::rdbuf() const throw ()
375  { return const_cast<strstreambuf*>(&_M_buf); }
376
377  void
378  ostrstream::freeze(bool freezeflag) throw ()
379  { _M_buf.freeze(freezeflag); }
380
381  char*
382  ostrstream::str() throw ()
383  { return _M_buf.str(); }
384
385  int
386  ostrstream::pcount() const throw ()
387  { return _M_buf.pcount(); }
388
389  strstream::strstream()
390  : basic_ios<char>(), basic_iostream<char>(0), _M_buf()
391  { basic_ios<char>::init(&_M_buf); }
392
393  strstream::strstream(char* s, int n, ios_base::openmode mode)
394  : basic_ios<char>(), basic_iostream<char>(0),
395    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
396  { basic_ios<char>::init(&_M_buf); }
397
398  strstream::~strstream() { }
399
400  strstreambuf*
401  strstream::rdbuf() const throw ()
402  { return const_cast<strstreambuf*>(&_M_buf); }
403
404  void
405  strstream::freeze(bool freezeflag) throw ()
406  { _M_buf.freeze(freezeflag); }
407
408  int
409  strstream::pcount() const throw ()
410  { return _M_buf.pcount(); }
411
412  char*
413  strstream::str() throw ()
414  { return _M_buf.str(); }
415
416_GLIBCXX_END_NAMESPACE_VERSION
417} // namespace
418