2005-02-16 Roland McGrath <roland@redhat.com>
[glibc/history.git] / libio / oldfileops.c
blobb9efca7aa8038e1ee6b496ea08e8f831acad02dd
1 /* Copyright (C) 1993, 1995, 1997-2003, 2004 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Written by Per Bothner <bothner@cygnus.com>.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18 02111-1307 USA.
20 As a special exception, if you link the code in this file with
21 files compiled with a GNU compiler to produce an executable,
22 that does not cause the resulting executable to be covered by
23 the GNU Lesser General Public License. This exception does not
24 however invalidate any other reasons why the executable file
25 might be covered by the GNU Lesser General Public License.
26 This exception applies to code released by its copyright holders
27 in files containing the exception. */
29 /* This is a compatibility file. If we don't build the libc with
30 versioning don't compile this file. */
31 #include <shlib-compat.h>
32 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
34 #ifndef _POSIX_SOURCE
35 # define _POSIX_SOURCE
36 #endif
37 #define _IO_USE_OLD_IO_FILE
38 #include "libioP.h"
39 #include <fcntl.h>
40 #include <sys/types.h>
41 #include <sys/stat.h>
42 #include <string.h>
43 #include <errno.h>
44 #ifdef __STDC__
45 #include <stdlib.h>
46 #endif
47 #ifndef errno
48 extern int errno;
49 #endif
50 #ifndef __set_errno
51 # define __set_errno(Val) errno = (Val)
52 #endif
55 #ifdef _LIBC
56 # define open(Name, Flags, Prot) __open (Name, Flags, Prot)
57 # define close(FD) __close (FD)
58 # define lseek(FD, Offset, Whence) __lseek (FD, Offset, Whence)
59 # define read(FD, Buf, NBytes) __read (FD, Buf, NBytes)
60 # define write(FD, Buf, NBytes) __write (FD, Buf, NBytes)
61 #endif
63 /* An fstream can be in at most one of put mode, get mode, or putback mode.
64 Putback mode is a variant of get mode.
66 In a filebuf, there is only one current position, instead of two
67 separate get and put pointers. In get mode, the current position
68 is that of gptr(); in put mode that of pptr().
70 The position in the buffer that corresponds to the position
71 in external file system is normally _IO_read_end, except in putback
72 mode, when it is _IO_save_end.
73 If the field _fb._offset is >= 0, it gives the offset in
74 the file as a whole corresponding to eGptr(). (?)
76 PUT MODE:
77 If a filebuf is in put mode, then all of _IO_read_ptr, _IO_read_end,
78 and _IO_read_base are equal to each other. These are usually equal
79 to _IO_buf_base, though not necessarily if we have switched from
80 get mode to put mode. (The reason is to maintain the invariant
81 that _IO_read_end corresponds to the external file position.)
82 _IO_write_base is non-NULL and usually equal to _IO_base_base.
83 We also have _IO_write_end == _IO_buf_end, but only in fully buffered mode.
84 The un-flushed character are those between _IO_write_base and _IO_write_ptr.
86 GET MODE:
87 If a filebuf is in get or putback mode, eback() != egptr().
88 In get mode, the unread characters are between gptr() and egptr().
89 The OS file position corresponds to that of egptr().
91 PUTBACK MODE:
92 Putback mode is used to remember "excess" characters that have
93 been sputbackc'd in a separate putback buffer.
94 In putback mode, the get buffer points to the special putback buffer.
95 The unread characters are the characters between gptr() and egptr()
96 in the putback buffer, as well as the area between save_gptr()
97 and save_egptr(), which point into the original reserve buffer.
98 (The pointers save_gptr() and save_egptr() are the values
99 of gptr() and egptr() at the time putback mode was entered.)
100 The OS position corresponds to that of save_egptr().
102 LINE BUFFERED OUTPUT:
103 During line buffered output, _IO_write_base==base() && epptr()==base().
104 However, ptr() may be anywhere between base() and ebuf().
105 This forces a call to filebuf::overflow(int C) on every put.
106 If there is more space in the buffer, and C is not a '\n',
107 then C is inserted, and pptr() incremented.
109 UNBUFFERED STREAMS:
110 If a filebuf is unbuffered(), the _shortbuf[1] is used as the buffer.
113 #define CLOSED_FILEBUF_FLAGS \
114 (_IO_IS_FILEBUF+_IO_NO_READS+_IO_NO_WRITES+_IO_TIED_PUT_GET)
117 void
118 attribute_compat_text_section
119 _IO_old_file_init (fp)
120 struct _IO_FILE_plus *fp;
122 /* POSIX.1 allows another file handle to be used to change the position
123 of our file descriptor. Hence we actually don't know the actual
124 position before we do the first fseek (and until a following fflush). */
125 fp->file._old_offset = _IO_pos_BAD;
126 fp->file._IO_file_flags |= CLOSED_FILEBUF_FLAGS;
128 INTUSE(_IO_link_in) (fp);
129 fp->file._vtable_offset = ((int) sizeof (struct _IO_FILE)
130 - (int) sizeof (struct _IO_FILE_complete));
131 fp->file._fileno = -1;
133 #if defined SHARED && defined _LIBC
134 if (__builtin_expect (&_IO_stdin_used != NULL, 1)
135 || (fp != (struct _IO_FILE_plus *) _IO_stdin
136 && fp != (struct _IO_FILE_plus *) _IO_stdout
137 && fp != (struct _IO_FILE_plus *) _IO_stderr))
138 /* The object is dynamically allocated and large enough. Initialize
139 the _mode element as well. */
140 ((struct _IO_FILE_complete *) fp)->_mode = -1;
141 #endif
145 attribute_compat_text_section
146 _IO_old_file_close_it (fp)
147 _IO_FILE *fp;
149 int write_status, close_status;
150 if (!_IO_file_is_open (fp))
151 return EOF;
153 write_status = _IO_old_do_flush (fp);
155 INTUSE(_IO_unsave_markers) (fp);
157 close_status = _IO_SYSCLOSE (fp);
159 /* Free buffer. */
160 INTUSE(_IO_setb) (fp, NULL, NULL, 0);
161 _IO_setg (fp, NULL, NULL, NULL);
162 _IO_setp (fp, NULL, NULL);
164 INTUSE(_IO_un_link) ((struct _IO_FILE_plus *) fp);
165 fp->_flags = _IO_MAGIC|CLOSED_FILEBUF_FLAGS;
166 fp->_fileno = -1;
167 fp->_old_offset = _IO_pos_BAD;
169 return close_status ? close_status : write_status;
172 void
173 attribute_compat_text_section
174 _IO_old_file_finish (fp, dummy)
175 _IO_FILE *fp;
176 int dummy;
178 if (_IO_file_is_open (fp))
180 _IO_old_do_flush (fp);
181 if (!(fp->_flags & _IO_DELETE_DONT_CLOSE))
182 _IO_SYSCLOSE (fp);
184 INTUSE(_IO_default_finish) (fp, 0);
187 _IO_FILE *
188 attribute_compat_text_section
189 _IO_old_file_fopen (fp, filename, mode)
190 _IO_FILE *fp;
191 const char *filename;
192 const char *mode;
194 int oflags = 0, omode;
195 int read_write, fdesc;
196 int oprot = 0666;
197 if (_IO_file_is_open (fp))
198 return 0;
199 switch (*mode++)
201 case 'r':
202 omode = O_RDONLY;
203 read_write = _IO_NO_WRITES;
204 break;
205 case 'w':
206 omode = O_WRONLY;
207 oflags = O_CREAT|O_TRUNC;
208 read_write = _IO_NO_READS;
209 break;
210 case 'a':
211 omode = O_WRONLY;
212 oflags = O_CREAT|O_APPEND;
213 read_write = _IO_NO_READS|_IO_IS_APPENDING;
214 break;
215 default:
216 __set_errno (EINVAL);
217 return NULL;
219 if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+'))
221 omode = O_RDWR;
222 read_write &= _IO_IS_APPENDING;
224 fdesc = open (filename, omode|oflags, oprot);
225 if (fdesc < 0)
226 return NULL;
227 fp->_fileno = fdesc;
228 _IO_mask_flags (fp, read_write,_IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING);
229 if (read_write & _IO_IS_APPENDING)
230 if (_IO_SEEKOFF (fp, (_IO_off_t)0, _IO_seek_end, _IOS_INPUT|_IOS_OUTPUT)
231 == _IO_pos_BAD && errno != ESPIPE)
232 return NULL;
233 INTUSE(_IO_link_in) ((struct _IO_FILE_plus *) fp);
234 return fp;
237 _IO_FILE *
238 attribute_compat_text_section
239 _IO_old_file_attach (fp, fd)
240 _IO_FILE *fp;
241 int fd;
243 if (_IO_file_is_open (fp))
244 return NULL;
245 fp->_fileno = fd;
246 fp->_flags &= ~(_IO_NO_READS+_IO_NO_WRITES);
247 fp->_flags |= _IO_DELETE_DONT_CLOSE;
248 /* Get the current position of the file. */
249 /* We have to do that since that may be junk. */
250 fp->_old_offset = _IO_pos_BAD;
251 if (_IO_SEEKOFF (fp, (_IO_off_t)0, _IO_seek_cur, _IOS_INPUT|_IOS_OUTPUT)
252 == _IO_pos_BAD && errno != ESPIPE)
253 return NULL;
254 return fp;
257 _IO_FILE *
258 attribute_compat_text_section
259 _IO_old_file_setbuf (fp, p, len)
260 _IO_FILE *fp;
261 char *p;
262 _IO_ssize_t len;
264 if (_IO_default_setbuf (fp, p, len) == NULL)
265 return NULL;
267 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
268 = fp->_IO_buf_base;
269 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
271 return fp;
274 static int old_do_write (_IO_FILE *, const char *, _IO_size_t) __THROW;
276 /* Write TO_DO bytes from DATA to FP.
277 Then mark FP as having empty buffers. */
280 attribute_compat_text_section
281 _IO_old_do_write (fp, data, to_do)
282 _IO_FILE *fp;
283 const char *data;
284 _IO_size_t to_do;
286 return (to_do == 0 || (_IO_size_t) old_do_write (fp, data, to_do) == to_do)
287 ? 0 : EOF;
290 static int
291 attribute_compat_text_section
292 old_do_write (fp, data, to_do)
293 _IO_FILE *fp;
294 const char *data;
295 _IO_size_t to_do;
297 _IO_size_t count;
298 if (fp->_flags & _IO_IS_APPENDING)
299 /* On a system without a proper O_APPEND implementation,
300 you would need to sys_seek(0, SEEK_END) here, but is
301 is not needed nor desirable for Unix- or Posix-like systems.
302 Instead, just indicate that offset (before and after) is
303 unpredictable. */
304 fp->_old_offset = _IO_pos_BAD;
305 else if (fp->_IO_read_end != fp->_IO_write_base)
307 _IO_off_t new_pos
308 = _IO_SYSSEEK (fp, fp->_IO_write_base - fp->_IO_read_end, 1);
309 if (new_pos == _IO_pos_BAD)
310 return 0;
311 fp->_old_offset = new_pos;
313 count = _IO_SYSWRITE (fp, data, to_do);
314 if (fp->_cur_column && count)
315 fp->_cur_column = INTUSE(_IO_adjust_column) (fp->_cur_column - 1, data,
316 count) + 1;
317 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
318 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_buf_base;
319 fp->_IO_write_end = ((fp->_flags & (_IO_LINE_BUF+_IO_UNBUFFERED))
320 ? fp->_IO_buf_base : fp->_IO_buf_end);
321 return count;
325 attribute_compat_text_section
326 _IO_old_file_underflow (fp)
327 _IO_FILE *fp;
329 _IO_ssize_t count;
330 #if 0
331 /* SysV does not make this test; take it out for compatibility */
332 if (fp->_flags & _IO_EOF_SEEN)
333 return (EOF);
334 #endif
336 if (fp->_flags & _IO_NO_READS)
338 fp->_flags |= _IO_ERR_SEEN;
339 __set_errno (EBADF);
340 return EOF;
342 if (fp->_IO_read_ptr < fp->_IO_read_end)
343 return *(unsigned char *) fp->_IO_read_ptr;
345 if (fp->_IO_buf_base == NULL)
347 /* Maybe we already have a push back pointer. */
348 if (fp->_IO_save_base != NULL)
350 free (fp->_IO_save_base);
351 fp->_flags &= ~_IO_IN_BACKUP;
353 INTUSE(_IO_doallocbuf) (fp);
356 /* Flush all line buffered files before reading. */
357 /* FIXME This can/should be moved to genops ?? */
358 if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED))
359 INTUSE(_IO_flush_all_linebuffered) ();
361 INTUSE(_IO_switch_to_get_mode) (fp);
363 /* This is very tricky. We have to adjust those
364 pointers before we call _IO_SYSREAD () since
365 we may longjump () out while waiting for
366 input. Those pointers may be screwed up. H.J. */
367 fp->_IO_read_base = fp->_IO_read_ptr = fp->_IO_buf_base;
368 fp->_IO_read_end = fp->_IO_buf_base;
369 fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
370 = fp->_IO_buf_base;
372 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
373 fp->_IO_buf_end - fp->_IO_buf_base);
374 if (count <= 0)
376 if (count == 0)
377 fp->_flags |= _IO_EOF_SEEN;
378 else
379 fp->_flags |= _IO_ERR_SEEN, count = 0;
381 fp->_IO_read_end += count;
382 if (count == 0)
383 return EOF;
384 if (fp->_old_offset != _IO_pos_BAD)
385 _IO_pos_adjust (fp->_old_offset, count);
386 return *(unsigned char *) fp->_IO_read_ptr;
390 attribute_compat_text_section
391 _IO_old_file_overflow (f, ch)
392 _IO_FILE *f;
393 int ch;
395 if (f->_flags & _IO_NO_WRITES) /* SET ERROR */
397 f->_flags |= _IO_ERR_SEEN;
398 __set_errno (EBADF);
399 return EOF;
401 /* If currently reading or no buffer allocated. */
402 if ((f->_flags & _IO_CURRENTLY_PUTTING) == 0)
404 /* Allocate a buffer if needed. */
405 if (f->_IO_write_base == 0)
407 INTUSE(_IO_doallocbuf) (f);
408 _IO_setg (f, f->_IO_buf_base, f->_IO_buf_base, f->_IO_buf_base);
410 /* Otherwise must be currently reading.
411 If _IO_read_ptr (and hence also _IO_read_end) is at the buffer end,
412 logically slide the buffer forwards one block (by setting the
413 read pointers to all point at the beginning of the block). This
414 makes room for subsequent output.
415 Otherwise, set the read pointers to _IO_read_end (leaving that
416 alone, so it can continue to correspond to the external position). */
417 if (f->_IO_read_ptr == f->_IO_buf_end)
418 f->_IO_read_end = f->_IO_read_ptr = f->_IO_buf_base;
419 f->_IO_write_ptr = f->_IO_read_ptr;
420 f->_IO_write_base = f->_IO_write_ptr;
421 f->_IO_write_end = f->_IO_buf_end;
422 f->_IO_read_base = f->_IO_read_ptr = f->_IO_read_end;
424 if (f->_flags & (_IO_LINE_BUF+_IO_UNBUFFERED))
425 f->_IO_write_end = f->_IO_write_ptr;
426 f->_flags |= _IO_CURRENTLY_PUTTING;
428 if (ch == EOF)
429 return _IO_old_do_flush (f);
430 if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */
431 if (_IO_old_do_flush (f) == EOF)
432 return EOF;
433 *f->_IO_write_ptr++ = ch;
434 if ((f->_flags & _IO_UNBUFFERED)
435 || ((f->_flags & _IO_LINE_BUF) && ch == '\n'))
436 if (_IO_old_do_flush (f) == EOF)
437 return EOF;
438 return (unsigned char) ch;
442 attribute_compat_text_section
443 _IO_old_file_sync (fp)
444 _IO_FILE *fp;
446 _IO_ssize_t delta;
447 int retval = 0;
449 /* char* ptr = cur_ptr(); */
450 if (fp->_IO_write_ptr > fp->_IO_write_base)
451 if (_IO_old_do_flush(fp)) return EOF;
452 delta = fp->_IO_read_ptr - fp->_IO_read_end;
453 if (delta != 0)
455 #ifdef TODO
456 if (_IO_in_backup (fp))
457 delta -= eGptr () - Gbase ();
458 #endif
459 _IO_off_t new_pos = _IO_SYSSEEK (fp, delta, 1);
460 if (new_pos != (_IO_off_t) EOF)
461 fp->_IO_read_end = fp->_IO_read_ptr;
462 #ifdef ESPIPE
463 else if (errno == ESPIPE)
464 ; /* Ignore error from unseekable devices. */
465 #endif
466 else
467 retval = EOF;
469 if (retval != EOF)
470 fp->_old_offset = _IO_pos_BAD;
471 /* FIXME: Cleanup - can this be shared? */
472 /* setg(base(), ptr, ptr); */
473 return retval;
476 _IO_off64_t
477 attribute_compat_text_section
478 _IO_old_file_seekoff (fp, offset, dir, mode)
479 _IO_FILE *fp;
480 _IO_off64_t offset;
481 int dir;
482 int mode;
484 _IO_off_t result;
485 _IO_off64_t delta, new_offset;
486 long count;
487 /* POSIX.1 8.2.3.7 says that after a call the fflush() the file
488 offset of the underlying file must be exact. */
489 int must_be_exact = (fp->_IO_read_base == fp->_IO_read_end
490 && fp->_IO_write_base == fp->_IO_write_ptr);
492 if (mode == 0)
493 dir = _IO_seek_cur, offset = 0; /* Don't move any pointers. */
495 /* Flush unwritten characters.
496 (This may do an unneeded write if we seek within the buffer.
497 But to be able to switch to reading, we would need to set
498 egptr to ptr. That can't be done in the current design,
499 which assumes file_ptr() is eGptr. Anyway, since we probably
500 end up flushing when we close(), it doesn't make much difference.)
501 FIXME: simulate mem-papped files. */
503 if (fp->_IO_write_ptr > fp->_IO_write_base || _IO_in_put_mode (fp))
504 if (INTUSE(_IO_switch_to_get_mode) (fp))
505 return EOF;
507 if (fp->_IO_buf_base == NULL)
509 /* It could be that we already have a pushback buffer. */
510 if (fp->_IO_read_base != NULL)
512 free (fp->_IO_read_base);
513 fp->_flags &= ~_IO_IN_BACKUP;
515 INTUSE(_IO_doallocbuf) (fp);
516 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
517 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
520 switch (dir)
522 case _IO_seek_cur:
523 /* Adjust for read-ahead (bytes is buffer). */
524 offset -= fp->_IO_read_end - fp->_IO_read_ptr;
525 if (fp->_old_offset == _IO_pos_BAD)
526 goto dumb;
527 /* Make offset absolute, assuming current pointer is file_ptr(). */
528 offset += fp->_old_offset;
530 dir = _IO_seek_set;
531 break;
532 case _IO_seek_set:
533 break;
534 case _IO_seek_end:
536 struct _G_stat64 st;
537 if (_IO_SYSSTAT (fp, &st) == 0 && S_ISREG (st.st_mode))
539 offset += st.st_size;
540 dir = _IO_seek_set;
542 else
543 goto dumb;
546 /* At this point, dir==_IO_seek_set. */
548 /* If we are only interested in the current position we've found it now. */
549 if (mode == 0)
550 return offset;
552 /* If destination is within current buffer, optimize: */
553 if (fp->_old_offset != _IO_pos_BAD && fp->_IO_read_base != NULL
554 && !_IO_in_backup (fp))
556 /* Offset relative to start of main get area. */
557 _IO_off_t rel_offset = (offset - fp->_old_offset
558 + (fp->_IO_read_end - fp->_IO_read_base));
559 if (rel_offset >= 0)
561 #if 0
562 if (_IO_in_backup (fp))
563 _IO_switch_to_main_get_area (fp);
564 #endif
565 if (rel_offset <= fp->_IO_read_end - fp->_IO_read_base)
567 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + rel_offset,
568 fp->_IO_read_end);
569 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
571 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
572 goto resync;
575 #ifdef TODO
576 /* If we have streammarkers, seek forward by reading ahead. */
577 if (_IO_have_markers (fp))
579 int to_skip = rel_offset
580 - (fp->_IO_read_ptr - fp->_IO_read_base);
581 if (ignore (to_skip) != to_skip)
582 goto dumb;
583 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
584 goto resync;
586 #endif
588 #ifdef TODO
589 if (rel_offset < 0 && rel_offset >= Bbase () - Bptr ())
591 if (!_IO_in_backup (fp))
592 _IO_switch_to_backup_area (fp);
593 gbump (fp->_IO_read_end + rel_offset - fp->_IO_read_ptr);
594 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
595 goto resync;
597 #endif
600 #ifdef TODO
601 INTUSE(_IO_unsave_markers) (fp);
602 #endif
604 if (fp->_flags & _IO_NO_READS)
605 goto dumb;
607 /* Try to seek to a block boundary, to improve kernel page management. */
608 new_offset = offset & ~(fp->_IO_buf_end - fp->_IO_buf_base - 1);
609 delta = offset - new_offset;
610 if (delta > fp->_IO_buf_end - fp->_IO_buf_base)
612 new_offset = offset;
613 delta = 0;
615 result = _IO_SYSSEEK (fp, new_offset, 0);
616 if (result < 0)
617 return EOF;
618 if (delta == 0)
619 count = 0;
620 else
622 count = _IO_SYSREAD (fp, fp->_IO_buf_base,
623 (must_be_exact
624 ? delta : fp->_IO_buf_end - fp->_IO_buf_base));
625 if (count < delta)
627 /* We weren't allowed to read, but try to seek the remainder. */
628 offset = count == EOF ? delta : delta-count;
629 dir = _IO_seek_cur;
630 goto dumb;
633 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + delta,
634 fp->_IO_buf_base + count);
635 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
636 fp->_old_offset = result + count;
637 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
638 return offset;
639 dumb:
641 INTUSE(_IO_unsave_markers) (fp);
642 result = _IO_SYSSEEK (fp, offset, dir);
643 if (result != EOF)
645 _IO_mask_flags (fp, 0, _IO_EOF_SEEN);
646 fp->_old_offset = result;
647 _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base);
648 _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base);
650 return result;
652 resync:
653 /* We need to do it since it is possible that the file offset in
654 the kernel may be changed behind our back. It may happen when
655 we fopen a file and then do a fork. One process may access the
656 the file and the kernel file offset will be changed. */
657 if (fp->_old_offset >= 0)
658 _IO_SYSSEEK (fp, fp->_old_offset, 0);
660 return offset;
663 _IO_ssize_t
664 attribute_compat_text_section
665 _IO_old_file_write (f, data, n)
666 _IO_FILE *f;
667 const void *data;
668 _IO_ssize_t n;
670 _IO_ssize_t to_do = n;
671 while (to_do > 0)
673 _IO_ssize_t count = write (f->_fileno, data, to_do);
674 if (count == EOF)
676 f->_flags |= _IO_ERR_SEEN;
677 break;
679 to_do -= count;
680 data = (void *) ((char *) data + count);
682 n -= to_do;
683 if (f->_old_offset >= 0)
684 f->_old_offset += n;
685 return n;
688 _IO_size_t
689 attribute_compat_text_section
690 _IO_old_file_xsputn (f, data, n)
691 _IO_FILE *f;
692 const void *data;
693 _IO_size_t n;
695 register const char *s = (char *) data;
696 _IO_size_t to_do = n;
697 int must_flush = 0;
698 _IO_size_t count;
700 if (n <= 0)
701 return 0;
702 /* This is an optimized implementation.
703 If the amount to be written straddles a block boundary
704 (or the filebuf is unbuffered), use sys_write directly. */
706 /* First figure out how much space is available in the buffer. */
707 count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */
708 if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING))
710 count = f->_IO_buf_end - f->_IO_write_ptr;
711 if (count >= n)
713 register const char *p;
714 for (p = s + n; p > s; )
716 if (*--p == '\n')
718 count = p - s + 1;
719 must_flush = 1;
720 break;
725 /* Then fill the buffer. */
726 if (count > 0)
728 if (count > to_do)
729 count = to_do;
730 if (count > 20)
732 #ifdef _LIBC
733 f->_IO_write_ptr = __mempcpy (f->_IO_write_ptr, s, count);
734 #else
735 memcpy (f->_IO_write_ptr, s, count);
736 f->_IO_write_ptr += count;
737 #endif
738 s += count;
740 else
742 register char *p = f->_IO_write_ptr;
743 register int i = (int) count;
744 while (--i >= 0)
745 *p++ = *s++;
746 f->_IO_write_ptr = p;
748 to_do -= count;
750 if (to_do + must_flush > 0)
752 _IO_size_t block_size, do_write;
753 /* Next flush the (full) buffer. */
754 if (__overflow (f, EOF) == EOF)
755 return n - to_do;
757 /* Try to maintain alignment: write a whole number of blocks.
758 dont_write is what gets left over. */
759 block_size = f->_IO_buf_end - f->_IO_buf_base;
760 do_write = to_do - (block_size >= 128 ? to_do % block_size : 0);
762 if (do_write)
764 count = old_do_write (f, s, do_write);
765 to_do -= count;
766 if (count < do_write)
767 return n - to_do;
770 /* Now write out the remainder. Normally, this will fit in the
771 buffer, but it's somewhat messier for line-buffered files,
772 so we let _IO_default_xsputn handle the general case. */
773 if (to_do)
774 to_do -= INTUSE(_IO_default_xsputn) (f, s+do_write, to_do);
776 return n - to_do;
780 const struct _IO_jump_t _IO_old_file_jumps =
782 JUMP_INIT_DUMMY,
783 JUMP_INIT(finish, _IO_old_file_finish),
784 JUMP_INIT(overflow, _IO_old_file_overflow),
785 JUMP_INIT(underflow, _IO_old_file_underflow),
786 JUMP_INIT(uflow, INTUSE(_IO_default_uflow)),
787 JUMP_INIT(pbackfail, INTUSE(_IO_default_pbackfail)),
788 JUMP_INIT(xsputn, _IO_old_file_xsputn),
789 JUMP_INIT(xsgetn, INTUSE(_IO_default_xsgetn)),
790 JUMP_INIT(seekoff, _IO_old_file_seekoff),
791 JUMP_INIT(seekpos, _IO_default_seekpos),
792 JUMP_INIT(setbuf, _IO_old_file_setbuf),
793 JUMP_INIT(sync, _IO_old_file_sync),
794 JUMP_INIT(doallocate, INTUSE(_IO_file_doallocate)),
795 JUMP_INIT(read, INTUSE(_IO_file_read)),
796 JUMP_INIT(write, _IO_old_file_write),
797 JUMP_INIT(seek, INTUSE(_IO_file_seek)),
798 JUMP_INIT(close, INTUSE(_IO_file_close)),
799 JUMP_INIT(stat, INTUSE(_IO_file_stat))
802 compat_symbol (libc, _IO_old_do_write, _IO_do_write, GLIBC_2_0);
803 compat_symbol (libc, _IO_old_file_attach, _IO_file_attach, GLIBC_2_0);
804 compat_symbol (libc, _IO_old_file_close_it, _IO_file_close_it, GLIBC_2_0);
805 compat_symbol (libc, _IO_old_file_finish, _IO_file_finish, GLIBC_2_0);
806 compat_symbol (libc, _IO_old_file_fopen, _IO_file_fopen, GLIBC_2_0);
807 compat_symbol (libc, _IO_old_file_init, _IO_file_init, GLIBC_2_0);
808 compat_symbol (libc, _IO_old_file_setbuf, _IO_file_setbuf, GLIBC_2_0);
809 compat_symbol (libc, _IO_old_file_sync, _IO_file_sync, GLIBC_2_0);
810 compat_symbol (libc, _IO_old_file_overflow, _IO_file_overflow, GLIBC_2_0);
811 compat_symbol (libc, _IO_old_file_seekoff, _IO_file_seekoff, GLIBC_2_0);
812 compat_symbol (libc, _IO_old_file_underflow, _IO_file_underflow, GLIBC_2_0);
813 compat_symbol (libc, _IO_old_file_write, _IO_file_write, GLIBC_2_0);
814 compat_symbol (libc, _IO_old_file_xsputn, _IO_file_xsputn, GLIBC_2_0);
816 #endif