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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997-2009 Oracle. All rights reserved.
*
* $Id$
*/
#include "db_config.h"
#include "db_int.h"
/*
* __os_seek --
* Seek to a page/byte offset in the file.
*/
int
__os_seek(env, fhp, pgno, pgsize, relative)
ENV *env;
DB_FH *fhp;
db_pgno_t pgno;
u_int32_t pgsize;
u_int32_t relative;
{
/* Yes, this really is how Microsoft designed their API. */
union {
__int64 bigint;
struct {
unsigned long low;
long high;
};
} offbytes;
DB_ENV *dbenv;
off_t offset;
int ret;
dbenv = env == NULL ? NULL : env->dbenv;
#if defined(HAVE_STATISTICS)
++fhp->seek_count;
#endif
offset = (off_t)pgsize * pgno + relative;
if (dbenv != NULL && FLD_ISSET(dbenv->verbose, DB_VERB_FILEOPS_ALL))
__db_msg(env,
"fileops: seek %s to %lu", fhp->name, (u_long)offset);
offbytes.bigint = offset;
ret = (SetFilePointer(fhp->handle, offbytes.low,
&offbytes.high, FILE_BEGIN) == (DWORD)-1) ? __os_get_syserr() : 0;
if (ret == 0) {
fhp->pgsize = pgsize;
fhp->pgno = pgno;
fhp->offset = relative;
} else {
__db_syserr(env, ret,
"seek: %lu: (%lu * %lu) + %lu", (u_long)offset,
(u_long)pgno, (u_long)pgsize, (u_long)relative);
ret = __os_posix_err(ret);
}
return (ret);
}
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