1/*
2 * Copyright (c) 1999
3 * Silicon Graphics Computer Systems, Inc.
4 *
5 * Copyright (c) 1999
6 * Boris Fomitchev
7 *
8 * This material is provided "as is", with absolutely no warranty expressed
9 * or implied. Any use is at your own risk.
10 *
11 * Permission to use or copy this software for any purpose is hereby granted
12 * without fee, provided the above notices are retained on all copies.
13 * Permission to modify the code and to distribute modified code is granted,
14 * provided the above notices are retained, and a notice that the code was
15 * modified is included with the above copyright notice.
16 *
17 */
18
19// Implementation of the classes in header <strstream>.
20// WARNING: The classes defined in <strstream> are DEPRECATED.  This
21// header is defined in section D.7.1 of the C++ standard, and it
22// MAY BE REMOVED in a future standard revision.  You should use the
23// header <sstream> instead.
24
25#include "stlport_prefix.h"
26
27#include <strstream>
28#include <algorithm>
29#include <limits>
30
31_STLP_BEGIN_NAMESPACE
32
33// strstreambuf constructor, destructor.
34strstreambuf::strstreambuf(streamsize initial_capacity)
35   : _M_alloc_fun(0), _M_free_fun(0),
36     _M_dynamic(true), _M_frozen(false), _M_constant(false) {
37  size_t n = (sizeof(streamsize) > sizeof(size_t)) ? __STATIC_CAST(size_t, (min)(__STATIC_CAST(streamsize, (numeric_limits<size_t>::max)()),
38                                                                                 (max)(initial_capacity, streamsize(16))))
39                                                   : __STATIC_CAST(size_t, (max)(initial_capacity, streamsize(16)));
40
41  char* buf = _M_alloc(n);
42  if (buf) {
43    setp(buf, buf + n);
44    setg(buf, buf, buf);
45  }
46}
47
48strstreambuf::strstreambuf(__alloc_fn alloc_f, __free_fn free_f)
49  : _M_alloc_fun(alloc_f), _M_free_fun(free_f),
50    _M_dynamic(true), _M_frozen(false), _M_constant(false) {
51  size_t n = 16;
52
53  char* buf = _M_alloc(n);
54  if (buf) {
55    setp(buf, buf + n);
56    setg(buf, buf, buf);
57  }
58}
59
60strstreambuf::strstreambuf(char* get, streamsize n, char* put)
61  : _M_alloc_fun(0), _M_free_fun(0),
62    _M_dynamic(false), _M_frozen(false), _M_constant(false) {
63  _M_setup(get, put, n);
64}
65
66strstreambuf::strstreambuf(signed char* get, streamsize n, signed char* put)
67  : _M_alloc_fun(0), _M_free_fun(0),
68    _M_dynamic(false), _M_frozen(false), _M_constant(false) {
69  _M_setup(__REINTERPRET_CAST(char*,get), __REINTERPRET_CAST(char*,put), n);
70}
71
72strstreambuf::strstreambuf(unsigned char* get, streamsize n,
73                           unsigned char* put)
74  : _M_alloc_fun(0), _M_free_fun(0),
75    _M_dynamic(false), _M_frozen(false), _M_constant(false) {
76  _M_setup(__REINTERPRET_CAST(char*,get), __REINTERPRET_CAST(char*,put), n);
77}
78
79strstreambuf::strstreambuf(const char* get, streamsize n)
80  : _M_alloc_fun(0), _M_free_fun(0),
81    _M_dynamic(false), _M_frozen(false), _M_constant(true) {
82  _M_setup(__CONST_CAST(char*,get), 0, n);
83}
84
85strstreambuf::strstreambuf(const signed char* get, streamsize n)
86  : _M_alloc_fun(0), _M_free_fun(0),
87    _M_dynamic(false), _M_frozen(false), _M_constant(true) {
88  _M_setup(__REINTERPRET_CAST(char*, __CONST_CAST(signed char*,get)), 0, n);
89}
90
91strstreambuf::strstreambuf(const unsigned char* get, streamsize n)
92  : _M_alloc_fun(0), _M_free_fun(0),
93    _M_dynamic(false), _M_frozen(false), _M_constant(true) {
94  _M_setup(__REINTERPRET_CAST(char*, __CONST_CAST(unsigned char*,get)), 0, n);
95}
96
97strstreambuf::~strstreambuf() {
98  if (_M_dynamic && !_M_frozen)
99    _M_free(eback());
100}
101
102void strstreambuf::freeze(bool frozenflag) {
103  if (_M_dynamic)
104    _M_frozen = frozenflag;
105}
106
107char* strstreambuf::str() {
108  freeze(true);
109  return eback();
110}
111
112int strstreambuf::pcount() const {
113  return int(pptr() ? pptr() - pbase() : 0);
114}
115
116strstreambuf::int_type strstreambuf::overflow(int_type c) {
117  if (c == traits_type::eof())
118    return traits_type::not_eof(c);
119
120  // Try to expand the buffer.
121  if (pptr() == epptr() && _M_dynamic && !_M_frozen && !_M_constant) {
122    ptrdiff_t old_size = epptr() - pbase();
123    ptrdiff_t new_size = (max)(2 * old_size, ptrdiff_t(1));
124
125    char* buf = _M_alloc(new_size);
126    if (buf) {
127      memcpy(buf, pbase(), old_size);
128
129      char* old_buffer = pbase();
130      bool reposition_get = false;
131      ptrdiff_t old_get_offset;
132      if (gptr() != 0) {
133        reposition_get = true;
134        old_get_offset = gptr() - eback();
135      }
136
137      setp(buf, buf + new_size);
138      pbump((int)old_size);
139
140      if (reposition_get)
141        setg(buf, buf + old_get_offset, buf + (max)(old_get_offset, old_size));
142
143      _M_free(old_buffer);
144    }
145  }
146
147  if (pptr() != epptr()) {
148    *pptr() = traits_type::to_char_type(c);
149    pbump(1);
150    return c;
151  }
152  else
153    return traits_type::eof();
154}
155
156strstreambuf::int_type strstreambuf::pbackfail(int_type c) {
157  if (gptr() != eback()) {
158    if (c == traits_type::eof()) {
159      gbump(-1);
160      return traits_type::not_eof(c);
161    }
162    else if (c == gptr()[-1]) {
163      gbump(-1);
164      return c;
165    }
166    else if (!_M_constant) {
167      gbump(-1);
168      *gptr() = traits_type::to_char_type(c);
169      return c;
170    }
171  }
172
173  return traits_type::eof();
174}
175
176strstreambuf::int_type strstreambuf::underflow() {
177  if (gptr() == egptr() && pptr() && pptr() > egptr())
178    setg(eback(), gptr(), pptr());
179
180  if (gptr() != egptr())
181    return (unsigned char) *gptr();
182  else
183    return _Traits::eof();
184}
185
186basic_streambuf<char, char_traits<char> >*
187strstreambuf::setbuf(char*, streamsize) {
188  return this;
189}
190
191strstreambuf::pos_type
192strstreambuf::seekoff(off_type off,
193                      ios_base::seekdir dir, ios_base::openmode mode) {
194  bool do_get = false;
195  bool do_put = false;
196
197  if ((mode & (ios_base::in | ios_base::out)) ==
198          (ios_base::in | ios_base::out) &&
199      (dir == ios_base::beg || dir == ios_base::end))
200    do_get = do_put = true;
201  else if (mode & ios_base::in)
202    do_get = true;
203  else if (mode & ios_base::out)
204    do_put = true;
205
206  // !gptr() is here because, according to D.7.1 paragraph 4, the seekable
207  // area is undefined if there is no get area.
208  if ((!do_get && !do_put) || (do_put && !pptr()) || !gptr())
209    return pos_type(off_type(-1));
210
211  char* seeklow  = eback();
212  char* seekhigh = epptr() ? epptr() : egptr();
213
214  off_type newoff;
215  switch(dir) {
216  case ios_base::beg:
217    newoff = 0;
218    break;
219  case ios_base::end:
220    newoff = seekhigh - seeklow;
221    break;
222  case ios_base::cur:
223    newoff = do_put ? pptr() - seeklow : gptr() - seeklow;
224    break;
225  default:
226    return pos_type(off_type(-1));
227  }
228
229  off += newoff;
230  if (off < 0 || off > seekhigh - seeklow)
231    return pos_type(off_type(-1));
232
233  if (do_put) {
234    if (seeklow + __STATIC_CAST(ptrdiff_t, off) < pbase()) {
235      setp(seeklow, epptr());
236      pbump((int)off);
237    }
238    else {
239      setp(pbase(), epptr());
240      pbump((int)(off - (pbase() - seeklow)));
241    }
242  }
243  if (do_get) {
244    if (off <= egptr() - seeklow)
245      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), egptr());
246    else if (off <= pptr() - seeklow)
247      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), pptr());
248    else
249      setg(seeklow, seeklow + __STATIC_CAST(ptrdiff_t, off), epptr());
250  }
251
252  return pos_type(newoff);
253}
254
255strstreambuf::pos_type
256strstreambuf::seekpos(pos_type pos, ios_base::openmode mode) {
257  return seekoff(pos - pos_type(off_type(0)), ios_base::beg, mode);
258}
259
260
261char* strstreambuf::_M_alloc(size_t n) {
262  if (_M_alloc_fun)
263    return __STATIC_CAST(char*,_M_alloc_fun(n));
264  else
265    return new char[n];
266}
267
268void strstreambuf::_M_free(char* p) {
269  if (p) {
270    if (_M_free_fun)
271      _M_free_fun(p);
272    else
273      delete[] p;
274  }
275}
276
277void strstreambuf::_M_setup(char* get, char* put, streamsize n) {
278  if (get) {
279    size_t N = n > 0 ? size_t(n) : n == 0 ? strlen(get) : size_t(INT_MAX);
280
281    if (put) {
282      setg(get, get, get + N);
283      setp(put, put + N);
284    }
285    else {
286      setg(get, get, get + N);
287    }
288  }
289}
290
291//----------------------------------------------------------------------
292// Class istrstream
293
294istrstream::istrstream(char* s)
295  : basic_istream<char, char_traits<char> >(0), _M_buf(s, 0) {
296  this->init(&_M_buf);
297}
298
299istrstream::istrstream(const char* s)
300  : basic_istream<char, char_traits<char> >(0), _M_buf(s, 0) {
301  this->init(&_M_buf);
302}
303
304istrstream::istrstream(char* s, streamsize n)
305  : basic_istream<char, char_traits<char> >(0), _M_buf(s, n) {
306  this->init(&_M_buf);
307}
308
309istrstream::istrstream(const char* s, streamsize n)
310  : basic_istream<char, char_traits<char> >(0), _M_buf(s, n) {
311  this->init(&_M_buf);
312}
313
314istrstream::~istrstream() {}
315
316strstreambuf* istrstream::rdbuf() const {
317  return __CONST_CAST(strstreambuf*,&_M_buf);
318}
319
320char* istrstream::str() { return _M_buf.str(); }
321
322//----------------------------------------------------------------------
323// Class ostrstream
324
325ostrstream::ostrstream()
326  : basic_ostream<char, char_traits<char> >(0), _M_buf() {
327  basic_ios<char, char_traits<char> >::init(&_M_buf);
328}
329
330ostrstream::ostrstream(char* s, int n, ios_base::openmode mode)
331  : basic_ostream<char, char_traits<char> >(0),
332    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s) {
333  basic_ios<char, char_traits<char> >::init(&_M_buf);
334}
335
336ostrstream::~ostrstream() {}
337
338strstreambuf* ostrstream::rdbuf() const {
339  return __CONST_CAST(strstreambuf*,&_M_buf);
340}
341
342void ostrstream::freeze(bool freezeflag) {
343  _M_buf.freeze(freezeflag);
344}
345
346char* ostrstream::str() {
347  return _M_buf.str();
348}
349
350int ostrstream::pcount() const {
351  return _M_buf.pcount();
352}
353
354
355//----------------------------------------------------------------------
356// Class strstream
357
358strstream::strstream()
359  : basic_iostream<char, char_traits<char> >(0), _M_buf() {
360  basic_ios<char, char_traits<char> >::init(&_M_buf);
361}
362
363strstream::strstream(char* s, int n, ios_base::openmode mode)
364  : basic_iostream<char, char_traits<char> >(0),
365    _M_buf(s, n, mode & ios_base::app ? s + strlen(s) : s) {
366  basic_ios<char, char_traits<char> >::init(&_M_buf);
367}
368
369strstream::~strstream() {}
370
371strstreambuf* strstream::rdbuf() const {
372  return __CONST_CAST(strstreambuf*,&_M_buf);
373}
374
375void strstream::freeze(bool freezeflag) {
376  _M_buf.freeze(freezeflag);
377}
378
379int strstream::pcount() const {
380  return _M_buf.pcount();
381}
382
383char* strstream::str() {
384  return _M_buf.str();
385}
386
387_STLP_END_NAMESPACE
388
389// Local Variables:
390// mode:C++
391// End:
392