gecko-dev/db/os/os_seek.c

45 строки
840 B
C

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 1998
* Sleepycat Software. All rights reserved.
*/
#include "config.h"
#ifndef lint
static const char sccsid[] = "@(#)os_seek.c 10.9 (Sleepycat) 4/19/98";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#endif
#include "db_int.h"
/*
* __os_seek --
* Seek to a page/byte offset in the file.
*
* PUBLIC: int __os_seek __P((int, size_t, db_pgno_t, u_int32_t, int, int));
*/
int
__os_seek(fd, pgsize, pageno, relative, isrewind, whence)
int fd;
size_t pgsize;
db_pgno_t pageno;
u_int32_t relative;
int isrewind, whence;
{
off_t offset;
offset = (off_t)pgsize * pageno + relative;
if (isrewind)
offset = -offset;
return (lseek(fd, offset, whence) == -1 ? errno : 0);
}