/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996, 1997
 *      Sleepycat Software.  All rights reserved.
 */
/*
 * Copyright (c) 1998 by Sun Microsystems, Inc.
 * All rights reserved.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)hash_conv.c   10.4 (Sleepycat) 9/15/97";
static const char sccsi2[] = "%W% (Sun) %G%";
#endif /* not lint */

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#endif

#include "db_int.h"
#include "db_page.h"
#include "db_swap.h"
#include "hash.h"

/*
 * __ham_pgin --
 *      Convert host-specific page layout from the host-independent format
 *      stored on disk.
 *
 * PUBLIC: int __ham_pgin __P((db_pgno_t, void *, DBT *));
 */
int
__ham_pgin(pg, pp, cookie)
        db_pgno_t pg;
        void *pp;
        DBT *cookie;
{
        DB_PGINFO *pginfo;
        u_int32_t tpgno;

        pginfo = (DB_PGINFO *)cookie->data;
        tpgno = PGNO((PAGE *)pp);
        if (pginfo->needswap)
                M_32_SWAP(tpgno);

        if (pg != PGNO_METADATA && pg != tpgno) {
                P_INIT(pp, pginfo->db_pagesize,
                    pg, PGNO_INVALID, PGNO_INVALID, 0, P_HASH);
                return (0);
        }

        if (!pginfo->needswap)
                return (0);
        return (pg == PGNO_METADATA ?
            __ham_mswap(pp) : __db_pgin(pg, pginfo->db_pagesize, pp));
}

/*
 * __ham_pgout --
 *      Convert host-specific page layout to the host-independent format
 *      stored on disk.
 *
 * PUBLIC: int __ham_pgout __P((db_pgno_t, void *, DBT *));
 */
int
__ham_pgout(pg, pp, cookie)
        db_pgno_t pg;
        void *pp;
        DBT *cookie;
{
        DB_PGINFO *pginfo;

        pginfo = (DB_PGINFO *)cookie->data;
        if (!pginfo->needswap)
                return (0);
        return (pg == PGNO_METADATA ?
            __ham_mswap(pp) : __db_pgout(pg, pginfo->db_pagesize, pp));
}

/*
 * __ham_mswap --
 *      Swap the bytes on the hash metadata page.
 *
 * PUBLIC: int __ham_mswap __P((void *));
 */
int
__ham_mswap(pg)
        void *pg;
{
        u_int8_t *p;
        int i;

        p = (u_int8_t *)pg;
        SWAP32(p);              /* lsn part 1 */
        SWAP32(p);              /* lsn part 2 */
        SWAP32(p);              /* pgno */
        SWAP32(p);              /* magic */
        SWAP32(p);              /* version */
        SWAP32(p);              /* pagesize */
        SWAP32(p);              /* ovfl_point */
        SWAP32(p);              /* last_freed */
        SWAP32(p);              /* max_bucket */
        SWAP32(p);              /* high_mask */
        SWAP32(p);              /* low_mask */
        SWAP32(p);              /* ffactor */
        SWAP32(p);              /* nelem */
        SWAP32(p);              /* h_charkey */
        SWAP32(p);              /* flags */
        for (i = 0; i < NCACHED; ++i)
                SWAP32(p);      /* spares */
        return (0);
}