You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
72 lines
1.4 KiB
72 lines
1.4 KiB
3 years ago
|
/*-
|
||
|
|
* See the file LICENSE for redistribution information.
|
||
|
|
*
|
||
|
|
* Copyright (c) 1997, 1998, 1999
|
||
|
|
* Sleepycat Software. All rights reserved.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "db_config.h"
|
||
|
|
|
||
|
|
#ifndef lint
|
||
|
|
static const char sccsid[] = "@(#)os_seek.c 11.3 (Sleepycat) 10/29/99";
|
||
|
|
#endif /* not lint */
|
||
|
|
|
||
|
|
#ifndef NO_SYSTEM_INCLUDES
|
||
|
|
#include <sys/types.h>
|
||
|
|
|
||
|
|
#include <errno.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
|
||
|
|
#ifdef _MSC_VER /* _WIN32 */
|
||
|
|
#include <io.h>
|
||
|
|
#else
|
||
|
|
#include <unistd.h>
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include "db_int.h"
|
||
|
|
#include "os_jump.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* CDB___os_seek --
|
||
|
|
* Seek to a page/byte offset in the file.
|
||
|
|
*
|
||
|
|
* PUBLIC: int CDB___os_seek
|
||
|
|
* PUBLIC: __P((DB_FH *, size_t, db_pgno_t, u_int32_t, int, DB_OS_SEEK));
|
||
|
|
*/
|
||
|
|
int
|
||
|
|
CDB___os_seek(fhp, pgsize, pageno, relative, isrewind, db_whence)
|
||
|
|
DB_FH *fhp;
|
||
|
|
size_t pgsize;
|
||
|
|
db_pgno_t pageno;
|
||
|
|
u_int32_t relative;
|
||
|
|
int isrewind;
|
||
|
|
DB_OS_SEEK db_whence;
|
||
|
|
{
|
||
|
|
off_t offset;
|
||
|
|
int whence;
|
||
|
|
|
||
|
|
switch (db_whence) {
|
||
|
|
case DB_OS_SEEK_CUR:
|
||
|
|
whence = SEEK_CUR;
|
||
|
|
break;
|
||
|
|
case DB_OS_SEEK_END:
|
||
|
|
whence = SEEK_END;
|
||
|
|
break;
|
||
|
|
case DB_OS_SEEK_SET:
|
||
|
|
whence = SEEK_SET;
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
return (EINVAL);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (CDB___db_jump.j_seek != NULL)
|
||
|
|
return (CDB___db_jump.j_seek(fhp->fd, pgsize, pageno,
|
||
|
|
relative, isrewind, whence) == -1 ? CDB___os_get_errno() : 0);
|
||
|
|
|
||
|
|
offset = (off_t)pgsize * pageno + relative;
|
||
|
|
if (isrewind)
|
||
|
|
offset = -offset;
|
||
|
|
return (lseek(fhp->fd, offset, whence) == -1 ? CDB___os_get_errno() : 0);
|
||
|
|
}
|