1 #include "stdio_impl.h"
2
__fseeko_unlocked(FILE * f,off_t off,int whence)3 int __fseeko_unlocked(FILE *f, off_t off, int whence)
4 {
5 /* Adjust relative offset for unread data in buffer, if any. */
6 if (whence == SEEK_CUR && f->rend) off -= f->rend - f->rpos;
7
8 /* Flush write buffer, and report error on failure. */
9 if (f->wpos != f->wbase) {
10 f->write(f, 0, 0);
11 if (!f->wpos) return -1;
12 }
13
14 /* Leave writing mode */
15 f->wpos = f->wbase = f->wend = 0;
16
17 /* Perform the underlying seek. */
18 if (lseek(f->fd, off, whence) < 0) return -1;
19
20 /* If seek succeeded, file is seekable and we discard read buffer. */
21 f->rpos = f->rend = 0;
22 f->flags &= ~F_EOF;
23
24 return 0;
25 }
26
__fseeko(FILE * f,off_t off,int whence)27 int __fseeko(FILE *f, off_t off, int whence)
28 {
29 int result;
30 FLOCK(f);
31 result = __fseeko_unlocked(f, off, whence);
32 FUNLOCK(f);
33 return result;
34 }
35
fseek(FILE * f,long off,int whence)36 int fseek(FILE *f, long off, int whence)
37 {
38 return __fseeko(f, off, whence);
39 }
40
41 weak_alias(__fseeko, fseeko);
42