1// strstream definitions -*- C++ -*-
2
3// Copyright (C) 2001, 2002, 2003, 2005 Free Software Foundation
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 2, 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// You should have received a copy of the GNU General Public License along
17// with this library; see the file COPYING.  If not, write to the Free
18// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
19// USA.
20
21// As a special exception, you may use this file as part of a free software
22// library without restriction.  Specifically, if other files instantiate
23// templates or use macros or inline functions from this file, or you compile
24// this file and link it with other files to produce an executable, this
25// file does not by itself cause the resulting executable to be covered by
26// the GNU General Public License.  This exception does not however
27// invalidate any other reasons why the executable file might be covered by
28// the GNU General Public License.
29
30/*
31 * Copyright (c) 1998
32 * Silicon Graphics Computer Systems, Inc.
33 *
34 * Permission to use, copy, modify, distribute and sell this software
35 * and its documentation for any purpose is hereby granted without fee,
36 * provided that the above copyright notice appear in all copies and
37 * that both that copyright notice and this permission notice appear
38 * in supporting documentation.  Silicon Graphics makes no
39 * representations about the suitability of this software for any
40 * purpose.  It is provided "as is" without express or implied warranty.
41 */
42
43// Implementation of the classes in header <strstream>.
44// WARNING: The classes defined in <strstream> are DEPRECATED.  This
45// header is defined in section D.7.1 of the C++ standard, and it
46// MAY BE REMOVED in a future standard revision.  You should use the
47// header <sstream> instead.
48
49#include <strstream>
50#include <algorithm>
51#include <new>
52#include <stdlib.h>
53#include <string.h>
54#include <limits.h>
55
56_GLIBCXX_BEGIN_NAMESPACE(std)
57
58  strstreambuf::strstreambuf(streamsize initial_capacity)
59  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(true),
60    _M_frozen(false), _M_constant(false)
61  {
62    streamsize n = std::max(initial_capacity, streamsize(16));
63
64    char* buf = _M_alloc(n);
65    if (buf)
66      {
67	setp(buf, buf + n);
68	setg(buf, buf, buf);
69      }
70  }
71
72  strstreambuf::strstreambuf(void* (*alloc_f)(size_t), void (*free_f)(void*))
73  : _Base(), _M_alloc_fun(alloc_f), _M_free_fun(free_f), _M_dynamic(true),
74    _M_frozen(false), _M_constant(false)
75  {
76    streamsize n = 16;
77
78    char* buf = _M_alloc(n);
79    if (buf)
80      {
81	setp(buf, buf + n);
82	setg(buf, buf, buf);
83      }
84  }
85
86  strstreambuf::strstreambuf(char* get, streamsize n, char* put)
87  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
88    _M_frozen(false), _M_constant(false)
89  { _M_setup(get, put, n); }
90
91  strstreambuf::strstreambuf(signed char* get, streamsize n, signed char* put)
92  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
93  _M_frozen(false), _M_constant(false)
94  { _M_setup(reinterpret_cast<char*>(get), reinterpret_cast<char*>(put), n); }
95
96  strstreambuf::strstreambuf(unsigned char* get, streamsize n,
97			     unsigned char* put)
98  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
99    _M_frozen(false), _M_constant(false)
100  { _M_setup(reinterpret_cast<char*>(get), reinterpret_cast<char*>(put), n); }
101
102  strstreambuf::strstreambuf(const char* get, streamsize n)
103  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
104    _M_frozen(false), _M_constant(true)
105  { _M_setup(const_cast<char*>(get), 0, n); }
106
107  strstreambuf::strstreambuf(const signed char* get, streamsize n)
108  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
109    _M_frozen(false), _M_constant(true)
110  { _M_setup(reinterpret_cast<char*>(const_cast<signed char*>(get)), 0, n); }
111
112  strstreambuf::strstreambuf(const unsigned char* get, streamsize n)
113  : _Base(), _M_alloc_fun(0), _M_free_fun(0), _M_dynamic(false),
114    _M_frozen(false), _M_constant(true)
115  { _M_setup(reinterpret_cast<char*>(const_cast<unsigned char*>(get)), 0, n); }
116
117  strstreambuf::~strstreambuf()
118  {
119    if (_M_dynamic && !_M_frozen)
120      _M_free(eback());
121  }
122
123  void
124  strstreambuf::freeze(bool frozenflag)
125  {
126    if (_M_dynamic)
127      _M_frozen = frozenflag;
128  }
129
130  char*
131  strstreambuf::str()
132  {
133    freeze(true);
134    return eback();
135  }
136
137  int
138  strstreambuf::pcount() const
139  { return pptr() ? pptr() - pbase() : 0; }
140
141  strstreambuf::int_type
142  strstreambuf::overflow(int_type c)
143  {
144    if (c == traits_type::eof())
145      return traits_type::not_eof(c);
146
147    // Try to expand the buffer.
148    if (pptr() == epptr() && _M_dynamic && !_M_frozen && !_M_constant)
149      {
150	ptrdiff_t old_size = epptr() - pbase();
151	ptrdiff_t new_size = std::max(ptrdiff_t(2 * old_size), ptrdiff_t(1));
152
153	char* buf = _M_alloc(new_size);
154	if (buf)
155	  {
156	    memcpy(buf, pbase(), old_size);
157	    char* old_buffer = pbase();
158	    bool reposition_get = false;
159	    ptrdiff_t old_get_offset;
160	    if (gptr() != 0)
161	      {
162		reposition_get = true;
163		old_get_offset = gptr() - eback();
164	      }
165
166	    setp(buf, buf + new_size);
167	    pbump(old_size);
168
169	    if (reposition_get)
170	      setg(buf, buf + old_get_offset, buf +
171		   std::max(old_get_offset, old_size));
172
173	    _M_free(old_buffer);
174	  }
175      }
176
177    if (pptr() != epptr())
178      {
179	*pptr() = c;
180	pbump(1);
181	return c;
182      }
183    else
184      return traits_type::eof();
185  }
186
187  strstreambuf::int_type
188  strstreambuf::pbackfail(int_type c)
189  {
190    if (gptr() != eback())
191      {
192      if (c == _Traits::eof())
193	{
194	  gbump(-1);
195	  return _Traits::not_eof(c);
196	}
197      else if (c == _Traits::to_int_type(gptr()[-1]))
198	{  // KLUDGE
199	  gbump(-1);
200	  return c;
201	}
202      else if (!_M_constant)
203	{
204	  gbump(-1);
205	  *gptr() = c;
206	  return c;
207	}
208    }
209    return _Traits::eof();
210  }
211
212  strstreambuf::int_type
213  strstreambuf::underflow()
214  {
215    if (gptr() == egptr() && pptr() && pptr() > egptr())
216      setg(eback(), gptr(), pptr());
217
218    if (gptr() != egptr())
219      return (unsigned char) *gptr();
220    else
221      return _Traits::eof();
222  }
223
224  basic_streambuf<char, char_traits<char> >*
225  strstreambuf::setbuf(char*, streamsize)
226  { return this; }
227
228  strstreambuf::pos_type
229  strstreambuf::seekoff(off_type off, ios_base::seekdir dir,
230			ios_base::openmode mode)
231  {
232    bool do_get = false;
233    bool do_put = false;
234
235    if ((mode & (ios_base::in | ios_base::out))
236	== (ios_base::in | ios_base::out) &&
237	(dir == ios_base::beg || dir == ios_base::end))
238      do_get = do_put = true;
239    else if (mode & ios_base::in)
240      do_get = true;
241    else if (mode & ios_base::out)
242      do_put = true;
243
244    // !gptr() is here because, according to D.7.1 paragraph 4, the seekable
245    // area is undefined if there is no get area.
246    if ((!do_get && !do_put) || (do_put && !pptr()) || !gptr())
247      return pos_type(off_type(-1));
248
249    char* seeklow  = eback();
250    char* seekhigh = epptr() ? epptr() : egptr();
251
252    off_type newoff;
253    switch (dir)
254      {
255      case ios_base::beg:
256	newoff = 0;
257	break;
258      case ios_base::end:
259	newoff = seekhigh - seeklow;
260	break;
261      case ios_base::cur:
262	newoff = do_put ? pptr() - seeklow : gptr() - seeklow;
263	break;
264      default:
265	return pos_type(off_type(-1));
266      }
267
268    off += newoff;
269    if (off < 0 || off > seekhigh - seeklow)
270      return pos_type(off_type(-1));
271
272    if (do_put)
273      {
274	if (seeklow + off < pbase())
275	  {
276	    setp(seeklow, epptr());
277	    pbump(off);
278	  }
279	else
280	  {
281	    setp(pbase(), epptr());
282	    pbump(off - (pbase() - seeklow));
283	  }
284      }
285    if (do_get)
286      {
287	if (off <= egptr() - seeklow)
288	  setg(seeklow, seeklow + off, egptr());
289	else if (off <= pptr() - seeklow)
290	  setg(seeklow, seeklow + off, pptr());
291	else
292	  setg(seeklow, seeklow + off, epptr());
293      }
294    return pos_type(newoff);
295  }
296
297  strstreambuf::pos_type
298  strstreambuf::seekpos(pos_type pos, ios_base::openmode mode)
299  { return seekoff(pos - pos_type(off_type(0)), ios_base::beg, mode); }
300
301  char*
302  strstreambuf::_M_alloc(size_t n)
303  {
304    if (_M_alloc_fun)
305      return static_cast<char*>(_M_alloc_fun(n));
306    else
307      return new char[n];
308  }
309
310  void
311  strstreambuf::_M_free(char* p)
312  {
313    if (p)
314      {
315	if (_M_free_fun)
316	  _M_free_fun(p);
317	else
318	  delete[] p;
319      }
320  }
321
322  void
323  strstreambuf::_M_setup(char* get, char* put, streamsize n)
324  {
325    if (get)
326      {
327	size_t N = n > 0 ? size_t(n) : n == 0 ? strlen(get) : size_t(INT_MAX);
328
329	if (put)
330	  {
331	    setg(get, get, put);
332	    setp(put, put + N);
333	  }
334	else
335	  setg(get, get, get + N);
336      }
337  }
338
339  istrstream::istrstream(char* s)
340  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
341  { basic_ios<char>::init(&_M_buf); }
342
343  istrstream::istrstream(const char* s)
344  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
345  { basic_ios<char>::init(&_M_buf); }
346
347  istrstream::istrstream(char* s, streamsize n)
348  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
349  { basic_ios<char>::init(&_M_buf); }
350
351  istrstream::istrstream(const char* s, streamsize n)
352  : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
353  { basic_ios<char>::init(&_M_buf); }
354
355  istrstream::~istrstream() { }
356
357  strstreambuf*
358  istrstream::rdbuf() const
359  { return const_cast<strstreambuf*>(&_M_buf); }
360
361  char*
362  istrstream::str()
363  { return _M_buf.str(); }
364
365  ostrstream::ostrstream()
366  : basic_ios<char>(), basic_ostream<char>(0), _M_buf()
367  { basic_ios<char>::init(&_M_buf); }
368
369  ostrstream::ostrstream(char* s, int n, ios_base::openmode mode)
370  : basic_ios<char>(), basic_ostream<char>(0),
371    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
372  { basic_ios<char>::init(&_M_buf); }
373
374  ostrstream::~ostrstream() {}
375
376  strstreambuf*
377  ostrstream::rdbuf() const
378  { return const_cast<strstreambuf*>(&_M_buf); }
379
380  void
381  ostrstream::freeze(bool freezeflag)
382  { _M_buf.freeze(freezeflag); }
383
384  char*
385  ostrstream::str()
386  { return _M_buf.str(); }
387
388  int
389  ostrstream::pcount() const
390  { return _M_buf.pcount(); }
391
392  strstream::strstream()
393  : basic_ios<char>(), basic_iostream<char>(0), _M_buf()
394  { basic_ios<char>::init(&_M_buf); }
395
396  strstream::strstream(char* s, int n, ios_base::openmode mode)
397  : basic_ios<char>(), basic_iostream<char>(0),
398    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
399  { basic_ios<char>::init(&_M_buf); }
400
401  strstream::~strstream() { }
402
403  strstreambuf*
404  strstream::rdbuf() const
405  { return const_cast<strstreambuf*>(&_M_buf); }
406
407  void
408  strstream::freeze(bool freezeflag)
409  { _M_buf.freeze(freezeflag); }
410
411  int
412  strstream::pcount() const
413  { return _M_buf.pcount(); }
414
415  char*
416  strstream::str()
417  { return _M_buf.str(); }
418
419_GLIBCXX_END_NAMESPACE
420