xref: /openbsd/gnu/gcc/libstdc++-v3/src/strstream.cc (revision 4bdff4be)
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       if (_M_free_fun)
315 	_M_free_fun(p);
316       else
317 	delete[] p;
318   }
319 
320   void
321   strstreambuf::_M_setup(char* get, char* put, streamsize n)
322   {
323     if (get)
324       {
325 	size_t N = n > 0 ? size_t(n) : n == 0 ? strlen(get) : size_t(INT_MAX);
326 
327 	if (put)
328 	  {
329 	    setg(get, get, put);
330 	    setp(put, put + N);
331 	  }
332 	else
333 	  setg(get, get, get + N);
334       }
335   }
336 
337   istrstream::istrstream(char* s)
338   : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
339   { basic_ios<char>::init(&_M_buf); }
340 
341   istrstream::istrstream(const char* s)
342   : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, 0)
343   { basic_ios<char>::init(&_M_buf); }
344 
345   istrstream::istrstream(char* s, streamsize n)
346   : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
347   { basic_ios<char>::init(&_M_buf); }
348 
349   istrstream::istrstream(const char* s, streamsize n)
350   : basic_ios<char>(), basic_istream<char>(0), _M_buf(s, n)
351   { basic_ios<char>::init(&_M_buf); }
352 
353   istrstream::~istrstream() { }
354 
355   strstreambuf*
356   istrstream::rdbuf() const
357   { return const_cast<strstreambuf*>(&_M_buf); }
358 
359   char*
360   istrstream::str()
361   { return _M_buf.str(); }
362 
363   ostrstream::ostrstream()
364   : basic_ios<char>(), basic_ostream<char>(0), _M_buf()
365   { basic_ios<char>::init(&_M_buf); }
366 
367   ostrstream::ostrstream(char* s, int n, ios_base::openmode mode)
368   : basic_ios<char>(), basic_ostream<char>(0),
369     _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
370   { basic_ios<char>::init(&_M_buf); }
371 
372   ostrstream::~ostrstream() {}
373 
374   strstreambuf*
375   ostrstream::rdbuf() const
376   { return const_cast<strstreambuf*>(&_M_buf); }
377 
378   void
379   ostrstream::freeze(bool freezeflag)
380   { _M_buf.freeze(freezeflag); }
381 
382   char*
383   ostrstream::str()
384   { return _M_buf.str(); }
385 
386   int
387   ostrstream::pcount() const
388   { return _M_buf.pcount(); }
389 
390   strstream::strstream()
391   : basic_ios<char>(), basic_iostream<char>(0), _M_buf()
392   { basic_ios<char>::init(&_M_buf); }
393 
394   strstream::strstream(char* s, int n, ios_base::openmode mode)
395   : basic_ios<char>(), basic_iostream<char>(0),
396     _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s)
397   { basic_ios<char>::init(&_M_buf); }
398 
399   strstream::~strstream() { }
400 
401   strstreambuf*
402   strstream::rdbuf() const
403   { return const_cast<strstreambuf*>(&_M_buf); }
404 
405   void
406   strstream::freeze(bool freezeflag)
407   { _M_buf.freeze(freezeflag); }
408 
409   int
410   strstream::pcount() const
411   { return _M_buf.pcount(); }
412 
413   char*
414   strstream::str()
415   { return _M_buf.str(); }
416 
417 _GLIBCXX_END_NAMESPACE
418