summary refs log tree commit diff
path: root/libio/wgenops.c
blob: 69f3b95896baba5457f2c9a1a43435f4ad07da4c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
/* Copyright (C) 1993-2015 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Written by Ulrich Drepper <drepper@cygnus.com>.
   Based on the single byte version by Per Bothner <bothner@cygnus.com>.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.

   As a special exception, if you link the code in this file with
   files compiled with a GNU compiler to produce an executable,
   that does not cause the resulting executable to be covered by
   the GNU Lesser General Public License.  This exception does not
   however invalidate any other reasons why the executable file
   might be covered by the GNU Lesser General Public License.
   This exception applies to code released by its copyright holders
   in files containing the exception.  */

/* Generic or default I/O operations. */

#include "libioP.h"
#include <stdlib.h>
#include <string.h>
#include <wchar.h>


#ifndef _LIBC
# define __wmemcpy(dst, src, n) wmemcpy (dst, src, n)
#endif


static int save_for_wbackup (_IO_FILE *fp, wchar_t *end_p) __THROW
#ifdef _LIBC
     internal_function
#endif
     ;

/* Return minimum _pos markers
   Assumes the current get area is the main get area. */
_IO_ssize_t
_IO_least_wmarker (fp, end_p)
     _IO_FILE *fp;
     wchar_t *end_p;
{
  _IO_ssize_t least_so_far = end_p - fp->_wide_data->_IO_read_base;
  struct _IO_marker *mark;
  for (mark = fp->_markers; mark != NULL; mark = mark->_next)
    if (mark->_pos < least_so_far)
      least_so_far = mark->_pos;
  return least_so_far;
}
libc_hidden_def (_IO_least_wmarker)

/* Switch current get area from backup buffer to (start of) main get area. */
void
_IO_switch_to_main_wget_area (fp)
     _IO_FILE *fp;
{
  wchar_t *tmp;
  fp->_flags &= ~_IO_IN_BACKUP;
  /* Swap _IO_read_end and _IO_save_end. */
  tmp = fp->_wide_data->_IO_read_end;
  fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_save_end;
  fp->_wide_data->_IO_save_end= tmp;
  /* Swap _IO_read_base and _IO_save_base. */
  tmp = fp->_wide_data->_IO_read_base;
  fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_save_base;
  fp->_wide_data->_IO_save_base = tmp;
  /* Set _IO_read_ptr. */
  fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_base;
}
libc_hidden_def (_IO_switch_to_main_wget_area)


/* Switch current get area from main get area to (end of) backup area. */
void
_IO_switch_to_wbackup_area (fp)
     _IO_FILE *fp;
{
  wchar_t *tmp;
  fp->_flags |= _IO_IN_BACKUP;
  /* Swap _IO_read_end and _IO_save_end. */
  tmp = fp->_wide_data->_IO_read_end;
  fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_save_end;
  fp->_wide_data->_IO_save_end = tmp;
  /* Swap _IO_read_base and _IO_save_base. */
  tmp = fp->_wide_data->_IO_read_base;
  fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_save_base;
  fp->_wide_data->_IO_save_base = tmp;
  /* Set _IO_read_ptr.  */
  fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end;
}
libc_hidden_def (_IO_switch_to_wbackup_area)


void
_IO_wsetb (f, b, eb, a)
     _IO_FILE *f;
     wchar_t *b;
     wchar_t *eb;
     int a;
{
  if (f->_wide_data->_IO_buf_base && !(f->_flags2 & _IO_FLAGS2_USER_WBUF))
    FREE_BUF (f->_wide_data->_IO_buf_base, _IO_wblen (f) * sizeof (wchar_t));
  f->_wide_data->_IO_buf_base = b;
  f->_wide_data->_IO_buf_end = eb;
  if (a)
    f->_flags2 &= ~_IO_FLAGS2_USER_WBUF;
  else
    f->_flags2 |= _IO_FLAGS2_USER_WBUF;
}
libc_hidden_def (_IO_wsetb)


wint_t
_IO_wdefault_pbackfail (fp, c)
     _IO_FILE *fp;
     wint_t c;
{
  if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
      && !_IO_in_backup (fp)
      && (wint_t) fp->_IO_read_ptr[-1] == c)
    --fp->_IO_read_ptr;
  else
    {
      /* Need to handle a filebuf in write mode (switch to read mode). FIXME!*/
      if (!_IO_in_backup (fp))
	{
	  /* We need to keep the invariant that the main get area
	     logically follows the backup area.  */
	  if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
	      && _IO_have_wbackup (fp))
	    {
	      if (save_for_wbackup (fp, fp->_wide_data->_IO_read_ptr))
		return WEOF;
	    }
	  else if (!_IO_have_wbackup (fp))
	    {
	      /* No backup buffer: allocate one. */
	      /* Use nshort buffer, if unused? (probably not)  FIXME */
	      int backup_size = 128;
	      wchar_t *bbuf = (wchar_t *) malloc (backup_size
						  * sizeof (wchar_t));
	      if (bbuf == NULL)
		return WEOF;
	      fp->_wide_data->_IO_save_base = bbuf;
	      fp->_wide_data->_IO_save_end = (fp->_wide_data->_IO_save_base
					      + backup_size);
	      fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_save_end;
	    }
	  fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_read_ptr;
	  _IO_switch_to_wbackup_area (fp);
	}
      else if (fp->_wide_data->_IO_read_ptr <= fp->_wide_data->_IO_read_base)
	{
	  /* Increase size of existing backup buffer. */
	  _IO_size_t new_size;
	  _IO_size_t old_size = (fp->_wide_data->_IO_read_end
				 - fp->_wide_data->_IO_read_base);
	  wchar_t *new_buf;
	  new_size = 2 * old_size;
	  new_buf = (wchar_t *) malloc (new_size * sizeof (wchar_t));
	  if (new_buf == NULL)
	    return WEOF;
	  __wmemcpy (new_buf + (new_size - old_size),
		     fp->_wide_data->_IO_read_base, old_size);
	  free (fp->_wide_data->_IO_read_base);
	  _IO_wsetg (fp, new_buf, new_buf + (new_size - old_size),
		     new_buf + new_size);
	  fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_read_ptr;
	}

      *--fp->_wide_data->_IO_read_ptr = c;
    }
  return c;
}
libc_hidden_def (_IO_wdefault_pbackfail)


void
_IO_wdefault_finish (fp, dummy)
     _IO_FILE *fp;
     int dummy;
{
  struct _IO_marker *mark;
  if (fp->_wide_data->_IO_buf_base && !(fp->_flags2 & _IO_FLAGS2_USER_WBUF))
    {
      FREE_BUF (fp->_wide_data->_IO_buf_base,
		_IO_wblen (fp) * sizeof (wchar_t));
      fp->_wide_data->_IO_buf_base = fp->_wide_data->_IO_buf_end = NULL;
    }

  for (mark = fp->_markers; mark != NULL; mark = mark->_next)
    mark->_sbuf = NULL;

  if (fp->_IO_save_base)
    {
      free (fp->_wide_data->_IO_save_base);
      fp->_IO_save_base = NULL;
    }

#ifdef _IO_MTSAFE_IO
  if (fp->_lock != NULL)
    _IO_lock_fini (*fp->_lock);
#endif

  _IO_un_link ((struct _IO_FILE_plus *) fp);
}
libc_hidden_def (_IO_wdefault_finish)


wint_t
_IO_wdefault_uflow (fp)
     _IO_FILE *fp;
{
  wint_t wch;
  wch = _IO_UNDERFLOW (fp);
  if (wch == WEOF)
    return WEOF;
  return *fp->_wide_data->_IO_read_ptr++;
}
libc_hidden_def (_IO_wdefault_uflow)


wint_t
__woverflow (f, wch)
     _IO_FILE *f;
     wint_t wch;
{
  if (f->_mode == 0)
    _IO_fwide (f, 1);
  return _IO_OVERFLOW (f, wch);
}
libc_hidden_def (__woverflow)


wint_t
__wuflow (fp)
     _IO_FILE *fp;
{
  if (fp->_mode < 0 || (fp->_mode == 0 && _IO_fwide (fp, 1) != 1))
    return WEOF;

  if (fp->_mode == 0)
    _IO_fwide (fp, 1);
  if (_IO_in_put_mode (fp))
    if (_IO_switch_to_wget_mode (fp) == EOF)
      return WEOF;
  if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
    return *fp->_wide_data->_IO_read_ptr++;
  if (_IO_in_backup (fp))
    {
      _IO_switch_to_main_wget_area (fp);
      if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
	return *fp->_wide_data->_IO_read_ptr++;
    }
  if (_IO_have_markers (fp))
    {
      if (save_for_wbackup (fp, fp->_wide_data->_IO_read_end))
	return WEOF;
    }
  else if (_IO_have_wbackup (fp))
    _IO_free_wbackup_area (fp);
  return _IO_UFLOW (fp);
}
libc_hidden_def (__wuflow)

wint_t
__wunderflow (fp)
     _IO_FILE *fp;
{
  if (fp->_mode < 0 || (fp->_mode == 0 && _IO_fwide (fp, 1) != 1))
    return WEOF;

  if (fp->_mode == 0)
    _IO_fwide (fp, 1);
  if (_IO_in_put_mode (fp))
    if (_IO_switch_to_wget_mode (fp) == EOF)
      return WEOF;
  if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
    return *fp->_wide_data->_IO_read_ptr;
  if (_IO_in_backup (fp))
    {
      _IO_switch_to_main_wget_area (fp);
      if (fp->_wide_data->_IO_read_ptr < fp->_wide_data->_IO_read_end)
	return *fp->_wide_data->_IO_read_ptr;
    }
  if (_IO_have_markers (fp))
    {
      if (save_for_wbackup (fp, fp->_wide_data->_IO_read_end))
	return WEOF;
    }
  else if (_IO_have_backup (fp))
    _IO_free_wbackup_area (fp);
  return _IO_UNDERFLOW (fp);
}
libc_hidden_def (__wunderflow)


_IO_size_t
_IO_wdefault_xsputn (f, data, n)
     _IO_FILE *f;
     const void *data;
     _IO_size_t n;
{
  const wchar_t *s = (const wchar_t *) data;
  _IO_size_t more = n;
  if (more <= 0)
    return 0;
  for (;;)
    {
      /* Space available. */
      _IO_ssize_t count = (f->_wide_data->_IO_write_end
			   - f->_wide_data->_IO_write_ptr);
      if (count > 0)
	{
	  if ((_IO_size_t) count > more)
	    count = more;
	  if (count > 20)
	    {
#ifdef _LIBC
	      f->_wide_data->_IO_write_ptr =
		__wmempcpy (f->_wide_data->_IO_write_ptr, s, count);
#else
	      memcpy (f->_wide_data->_IO_write_ptr, s, count);
	      f->_wide_data->_IO_write_ptr += count;
#endif
	      s += count;
            }
	  else if (count <= 0)
	    count = 0;
	  else
	    {
	      wchar_t *p = f->_wide_data->_IO_write_ptr;
	      _IO_ssize_t i;
	      for (i = count; --i >= 0; )
		*p++ = *s++;
	      f->_wide_data->_IO_write_ptr = p;
            }
	  more -= count;
        }
      if (more == 0 || __woverflow (f, *s++) == WEOF)
	break;
      more--;
    }
  return n - more;
}
libc_hidden_def (_IO_wdefault_xsputn)


_IO_size_t
_IO_wdefault_xsgetn (fp, data, n)
     _IO_FILE *fp;
     void *data;
     _IO_size_t n;
{
  _IO_size_t more = n;
  wchar_t *s = (wchar_t*) data;
  for (;;)
    {
      /* Data available. */
      _IO_ssize_t count = (fp->_wide_data->_IO_read_end
			   - fp->_wide_data->_IO_read_ptr);
      if (count > 0)
	{
	  if ((_IO_size_t) count > more)
	    count = more;
	  if (count > 20)
	    {
#ifdef _LIBC
	      s = __wmempcpy (s, fp->_wide_data->_IO_read_ptr, count);
#else
	      memcpy (s, fp->_wide_data->_IO_read_ptr, count);
	      s += count;
#endif
	      fp->_wide_data->_IO_read_ptr += count;
	    }
	  else if (count <= 0)
	    count = 0;
	  else
	    {
	      wchar_t *p = fp->_wide_data->_IO_read_ptr;
	      int i = (int) count;
	      while (--i >= 0)
		*s++ = *p++;
	      fp->_wide_data->_IO_read_ptr = p;
            }
            more -= count;
        }
      if (more == 0 || __wunderflow (fp) == WEOF)
	break;
    }
  return n - more;
}
libc_hidden_def (_IO_wdefault_xsgetn)


void
_IO_wdoallocbuf (fp)
     _IO_FILE *fp;
{
  if (fp->_wide_data->_IO_buf_base)
    return;
  if (!(fp->_flags & _IO_UNBUFFERED))
    if ((wint_t)_IO_WDOALLOCATE (fp) != WEOF)
      return;
  _IO_wsetb (fp, fp->_wide_data->_shortbuf,
		     fp->_wide_data->_shortbuf + 1, 0);
}
libc_hidden_def (_IO_wdoallocbuf)


int
_IO_wdefault_doallocate (fp)
     _IO_FILE *fp;
{
  wchar_t *buf;

  ALLOC_WBUF (buf, _IO_BUFSIZ, EOF);
  _IO_wsetb (fp, buf, buf + _IO_BUFSIZ, 1);
  return 1;
}
libc_hidden_def (_IO_wdefault_doallocate)


int
_IO_switch_to_wget_mode (fp)
     _IO_FILE *fp;
{
  if (fp->_wide_data->_IO_write_ptr > fp->_wide_data->_IO_write_base)
    if ((wint_t)_IO_WOVERFLOW (fp, WEOF) == WEOF)
      return EOF;
  if (_IO_in_backup (fp))
    fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_backup_base;
  else
    {
      fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_buf_base;
      if (fp->_wide_data->_IO_write_ptr > fp->_wide_data->_IO_read_end)
	fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_write_ptr;
    }
  fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_write_ptr;

  fp->_wide_data->_IO_write_base = fp->_wide_data->_IO_write_ptr
    = fp->_wide_data->_IO_write_end = fp->_wide_data->_IO_read_ptr;

  fp->_flags &= ~_IO_CURRENTLY_PUTTING;
  return 0;
}
libc_hidden_def (_IO_switch_to_wget_mode)

void
_IO_free_wbackup_area (fp)
     _IO_FILE *fp;
{
  if (_IO_in_backup (fp))
    _IO_switch_to_main_wget_area (fp);  /* Just in case. */
  free (fp->_wide_data->_IO_save_base);
  fp->_wide_data->_IO_save_base = NULL;
  fp->_wide_data->_IO_save_end = NULL;
  fp->_wide_data->_IO_backup_base = NULL;
}
libc_hidden_def (_IO_free_wbackup_area)

#if 0
int
_IO_switch_to_wput_mode (fp)
     _IO_FILE *fp;
{
  fp->_wide_data->_IO_write_base = fp->_wide_data->_IO_read_ptr;
  fp->_wide_data->_IO_write_ptr = fp->_wide_data->_IO_read_ptr;
  /* Following is wrong if line- or un-buffered? */
  fp->_wide_data->_IO_write_end = (fp->_flags & _IO_IN_BACKUP
				   ? fp->_wide_data->_IO_read_end
				   : fp->_wide_data->_IO_buf_end);

  fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end;
  fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_read_end;

  fp->_flags |= _IO_CURRENTLY_PUTTING;
  return 0;
}
#endif


static int
#ifdef _LIBC
internal_function
#endif
save_for_wbackup (fp, end_p)
     _IO_FILE *fp;
     wchar_t *end_p;
{
  /* Append [_IO_read_base..end_p] to backup area. */
  _IO_ssize_t least_mark = _IO_least_wmarker (fp, end_p);
  /* needed_size is how much space we need in the backup area. */
  _IO_size_t needed_size = ((end_p - fp->_wide_data->_IO_read_base)
			    - least_mark);
  /* FIXME: Dubious arithmetic if pointers are NULL */
  _IO_size_t current_Bsize = (fp->_wide_data->_IO_save_end
			      - fp->_wide_data->_IO_save_base);
  _IO_size_t avail; /* Extra space available for future expansion. */
  _IO_ssize_t delta;
  struct _IO_marker *mark;
  if (needed_size > current_Bsize)
    {
      wchar_t *new_buffer;
      avail = 100;
      new_buffer = (wchar_t *) malloc ((avail + needed_size)
				       * sizeof (wchar_t));
      if (new_buffer == NULL)
	return EOF;		/* FIXME */
      if (least_mark < 0)
	{
#ifdef _LIBC
	  __wmempcpy (__wmempcpy (new_buffer + avail,
				  fp->_wide_data->_IO_save_end + least_mark,
				  -least_mark),
		      fp->_wide_data->_IO_read_base,
		      end_p - fp->_wide_data->_IO_read_base);
#else
	  memcpy (new_buffer + avail,
		  fp->_wide_data->_IO_save_end + least_mark,
		  -least_mark * sizeof (wchar_t));
	  memcpy (new_buffer + avail - least_mark,
		  fp->_wide_data->_IO_read_base,
		  (end_p - fp->_wide_data->_IO_read_base) * sizeof (wchar_t));
#endif
	}
      else
	{
#ifdef _LIBC
	  __wmemcpy (new_buffer + avail,
		     fp->_wide_data->_IO_read_base + least_mark,
		     needed_size);
#else
	  memcpy (new_buffer + avail,
		  fp->_wide_data->_IO_read_base + least_mark,
		  needed_size * sizeof (wchar_t));
#endif
	}
      free (fp->_wide_data->_IO_save_base);
      fp->_wide_data->_IO_save_base = new_buffer;
      fp->_wide_data->_IO_save_end = new_buffer + avail + needed_size;
    }
  else
    {
      avail = current_Bsize - needed_size;
      if (least_mark < 0)
	{
#ifdef _LIBC
	  __wmemmove (fp->_wide_data->_IO_save_base + avail,
		      fp->_wide_data->_IO_save_end + least_mark,
		      -least_mark);
	  __wmemcpy (fp->_wide_data->_IO_save_base + avail - least_mark,
		     fp->_wide_data->_IO_read_base,
		     end_p - fp->_wide_data->_IO_read_base);
#else
	  memmove (fp->_wide_data->_IO_save_base + avail,
		   fp->_wide_data->_IO_save_end + least_mark,
		   -least_mark * sizeof (wchar_t));
	  memcpy (fp->_wide_data->_IO_save_base + avail - least_mark,
		  fp->_wide_data->_IO_read_base,
		  (end_p - fp->_wide_data->_IO_read_base) * sizeof (wchar_t));
#endif
	}
      else if (needed_size > 0)
#ifdef _LIBC
	__wmemcpy (fp->_wide_data->_IO_save_base + avail,
		   fp->_wide_data->_IO_read_base + least_mark,
		   needed_size);
#else
	memcpy (fp->_wide_data->_IO_save_base + avail,
		fp->_wide_data->_IO_read_base + least_mark,
		needed_size * sizeof (wchar_t));
#endif
    }
  fp->_wide_data->_IO_backup_base = fp->_wide_data->_IO_save_base + avail;
  /* Adjust all the streammarkers. */
  delta = end_p - fp->_wide_data->_IO_read_base;
  for (mark = fp->_markers; mark != NULL; mark = mark->_next)
    mark->_pos -= delta;
  return 0;
}

wint_t
_IO_sputbackwc (fp, c)
     _IO_FILE *fp;
     wint_t c;
{
  wint_t result;

  if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base
      && (wchar_t)fp->_wide_data->_IO_read_ptr[-1] == (wchar_t) c)
    {
      fp->_wide_data->_IO_read_ptr--;
      result = c;
    }
  else
    result = _IO_PBACKFAIL (fp, c);

  if (result != WEOF)
    fp->_flags &= ~_IO_EOF_SEEN;

  return result;
}
libc_hidden_def (_IO_sputbackwc)

wint_t
_IO_sungetwc (fp)
     _IO_FILE *fp;
{
  wint_t result;

  if (fp->_wide_data->_IO_read_ptr > fp->_wide_data->_IO_read_base)
    {
      fp->_wide_data->_IO_read_ptr--;
      result = *fp->_wide_data->_IO_read_ptr;
    }
  else
    result = _IO_PBACKFAIL (fp, EOF);

  if (result != WEOF)
    fp->_flags &= ~_IO_EOF_SEEN;

  return result;
}


unsigned
_IO_adjust_wcolumn (start, line, count)
     unsigned start;
     const wchar_t *line;
     int count;
{
  const wchar_t *ptr = line + count;
  while (ptr > line)
    if (*--ptr == L'\n')
      return line + count - ptr - 1;
  return start + count;
}

void
_IO_init_wmarker (marker, fp)
     struct _IO_marker *marker;
     _IO_FILE *fp;
{
  marker->_sbuf = fp;
  if (_IO_in_put_mode (fp))
    _IO_switch_to_wget_mode (fp);
  if (_IO_in_backup (fp))
    marker->_pos = fp->_wide_data->_IO_read_ptr - fp->_wide_data->_IO_read_end;
  else
    marker->_pos = (fp->_wide_data->_IO_read_ptr
		    - fp->_wide_data->_IO_read_base);

  /* Should perhaps sort the chain? */
  marker->_next = fp->_markers;
  fp->_markers = marker;
}

#define BAD_DELTA EOF

/* Return difference between MARK and current position of MARK's stream. */
int
_IO_wmarker_delta (mark)
     struct _IO_marker *mark;
{
  int cur_pos;
  if (mark->_sbuf == NULL)
    return BAD_DELTA;
  if (_IO_in_backup (mark->_sbuf))
    cur_pos = (mark->_sbuf->_wide_data->_IO_read_ptr
	       - mark->_sbuf->_wide_data->_IO_read_end);
  else
    cur_pos = (mark->_sbuf->_wide_data->_IO_read_ptr
	       - mark->_sbuf->_wide_data->_IO_read_base);
  return mark->_pos - cur_pos;
}

int
_IO_seekwmark (fp, mark, delta)
     _IO_FILE *fp;
     struct _IO_marker *mark;
     int delta;
{
  if (mark->_sbuf != fp)
    return EOF;
 if (mark->_pos >= 0)
    {
      if (_IO_in_backup (fp))
	_IO_switch_to_main_wget_area (fp);
      fp->_wide_data->_IO_read_ptr = (fp->_wide_data->_IO_read_base
				      + mark->_pos);
    }
  else
    {
      if (!_IO_in_backup (fp))
	_IO_switch_to_wbackup_area (fp);
      fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end + mark->_pos;
    }
  return 0;
}

void
_IO_unsave_wmarkers (fp)
     _IO_FILE *fp;
{
  struct _IO_marker *mark = fp->_markers;
  if (mark)
    {
#ifdef TODO
      streampos offset = seekoff (0, ios::cur, ios::in);
      if (offset != EOF)
	{
	  offset += eGptr () - Gbase ();
	  for ( ; mark != NULL; mark = mark->_next)
	    mark->set_streampos (mark->_pos + offset);
	}
    else
      {
	for ( ; mark != NULL; mark = mark->_next)
	  mark->set_streampos (EOF);
      }
#endif
      fp->_markers = 0;
    }

  if (_IO_have_backup (fp))
    _IO_free_wbackup_area (fp);
}