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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 1998, 1999, 2000
* Sleepycat Software. All rights reserved.
*/
#include "db_config.h"
#ifndef lint
static const char revid[] = "$Id: os_seek.c,v 11.8 2000/05/17 19:30:19 bostic Exp $";
#endif /* not lint */
#include "db_int.h"
#include "os_jump.h"
/*
* __os_seek --
* Seek to a page/byte offset in the file.
*/
int
__os_seek(dbenv, fhp, pgsize, pageno, relative, isrewind, db_whence)
DB_ENV *dbenv;
DB_FH *fhp;
size_t pgsize;
db_pgno_t pageno;
u_int32_t relative;
int isrewind;
DB_OS_SEEK db_whence;
{
__int64 offset;
int ret, 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 (__db_jump.j_seek != NULL)
ret = __db_jump.j_seek(fhp->fd, pgsize, pageno,
relative, isrewind, whence);
else {
offset = (__int64)pgsize * pageno + relative;
if (isrewind)
offset = -offset;
ret = _lseeki64(
fhp->fd, offset, whence) == -1 ? __os_get_errno() : 0;
}
if (ret != 0)
__db_err(dbenv, "seek: %lu %d %d: %s",
(u_long)pgsize * pageno + relative,
isrewind, db_whence, strerror(ret));
return (ret);
}
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