Files
cpython-source-deps/hash/hash_conv.c
2017-09-04 13:40:25 -05:00

111 lines
2.3 KiB
C

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996,2008 Oracle. All rights reserved.
*
* $Id: hash_conv.c 63573 2008-05-23 21:43:21Z trent.nelson $
*/
#include "db_config.h"
#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_swap.h"
#include "dbinc/hash.h"
/*
* __ham_pgin --
* Convert host-specific page layout from the host-independent format
* stored on disk.
*
* PUBLIC: int __ham_pgin __P((DB *, db_pgno_t, void *, DBT *));
*/
int
__ham_pgin(dbp, pg, pp, cookie)
DB *dbp;
db_pgno_t pg;
void *pp;
DBT *cookie;
{
DB_PGINFO *pginfo;
PAGE *h;
h = pp;
pginfo = (DB_PGINFO *)cookie->data;
/*
* The hash access method does blind reads of pages, causing them
* to be created. If the type field isn't set it's one of them,
* initialize the rest of the page and return.
*/
if (h->type != P_HASHMETA && h->pgno == PGNO_INVALID) {
P_INIT(pp, (db_indx_t)pginfo->db_pagesize,
pg, PGNO_INVALID, PGNO_INVALID, 0, P_HASH);
return (0);
}
if (!F_ISSET(pginfo, DB_AM_SWAP))
return (0);
return (h->type == P_HASHMETA ? __ham_mswap(dbp->env, pp) :
__db_byteswap(dbp, pg, pp, pginfo->db_pagesize, 1));
}
/*
* __ham_pgout --
* Convert host-specific page layout to the host-independent format
* stored on disk.
*
* PUBLIC: int __ham_pgout __P((DB *, db_pgno_t, void *, DBT *));
*/
int
__ham_pgout(dbp, pg, pp, cookie)
DB *dbp;
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 (h->type == P_HASHMETA ? __ham_mswap(dbp->env, pp) :
__db_byteswap(dbp, pg, pp, pginfo->db_pagesize, 0));
}
/*
* __ham_mswap --
* Swap the bytes on the hash metadata page.
*
* PUBLIC: int __ham_mswap __P((ENV *, void *));
*/
int
__ham_mswap(env, pg)
ENV *env;
void *pg;
{
u_int8_t *p;
int i;
COMPQUIET(env, NULL);
__db_metaswap(pg);
p = (u_int8_t *)pg + sizeof(DBMETA);
SWAP32(p); /* max_bucket */
SWAP32(p); /* high_mask */
SWAP32(p); /* low_mask */
SWAP32(p); /* ffactor */
SWAP32(p); /* nelem */
SWAP32(p); /* h_charkey */
for (i = 0; i < NCACHED; ++i)
SWAP32(p); /* spares */
p += 59 * sizeof(u_int32_t); /* unused */
SWAP32(p); /* crypto_magic */
return (0);
}