bt_conv.c

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996-2005
 *      Sleepycat Software.  All rights reserved.
 *
 * $Id: bt_conv.c,v 12.2 2005/06/16 20:20:13 bostic Exp $
 */

#include "db_config.h"

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

#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_swap.h"
#include "dbinc/btree.h"

/*
 * __bam_pgin --
 *      Convert host-specific page layout from the host-independent format
 *      stored on disk.
 *
 * PUBLIC: int __bam_pgin __P((DB_ENV *, DB *, db_pgno_t, void *, DBT *));
 */
int
__bam_pgin(dbenv, dummydbp, pg, pp, cookie)
        DB_ENV *dbenv;
        DB *dummydbp;
        db_pgno_t pg;
        void *pp;
        DBT *cookie;
{
        DB_PGINFO *pginfo;
        PAGE *h;

        pginfo = (DB_PGINFO *)cookie->data;
        if (!F_ISSET(pginfo, DB_AM_SWAP))
                return (0);

        h = pp;
        return (TYPE(h) == P_BTREEMETA ?  __bam_mswap(pp) :
            __db_byteswap(dbenv, dummydbp, pg, pp, pginfo->db_pagesize, 1));
}

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

        pginfo = (DB_PGINFO *)cookie->data;
        if (!F_ISSET(pginfo, DB_AM_SWAP))
                return (0);

        h = pp;
        return (TYPE(h) == P_BTREEMETA ?  __bam_mswap(pp) :
            __db_byteswap(dbenv, dummydbp, pg, pp, pginfo->db_pagesize, 0));
}

/*
 * __bam_mswap --
 *      Swap the bytes on the btree metadata page.
 *
 * PUBLIC: int __bam_mswap __P((PAGE *));
 */
int
__bam_mswap(pg)
        PAGE *pg;
{
        u_int8_t *p;

        __db_metaswap(pg);

        p = (u_int8_t *)pg + sizeof(DBMETA);

        p += sizeof(u_int32_t); /* unused */
        SWAP32(p);              /* minkey */
        SWAP32(p);              /* re_len */
        SWAP32(p);              /* re_pad */
        SWAP32(p);              /* root */
        p += 92 * sizeof(u_int32_t); /* unused */
        SWAP32(p);              /* crypto_magic */

        return (0);
}

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