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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997-2002
* Sleepycat Software. All rights reserved.
*/
#include "db_config.h"
#ifndef lint
static const char revid[] = "$Id: os_seek.c,v 11.18 2002/07/12 18:56:52 bostic Exp $";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <stdlib.h>
#include <string.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((DB_ENV *,
* PUBLIC: DB_FH *, size_t, db_pgno_t, u_int32_t, int, DB_OS_SEEK));
*/
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;
{
off_t 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_GLOBAL(j_seek) != NULL)
ret = DB_GLOBAL(j_seek)(fhp->fd,
pgsize, pageno, relative, isrewind, whence);
else {
offset = (off_t)pgsize * pageno + relative;
if (isrewind)
offset = -offset;
do {
ret = lseek(fhp->fd, offset, whence) == -1 ?
__os_get_errno() : 0;
} while (ret == EINTR);
}
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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