1 /*-
2  * See the file LICENSE for redistribution information.
3  *
4  * Copyright (c) 1996, 1997
5  *	Sleepycat Software.  All rights reserved.
6  */
7 /*
8  * Copyright (c) 1998 by Sun Microsystems, Inc.
9  * All rights reserved.
10  */
11 
12 #include "config.h"
13 
14 #ifndef lint
15 static const char sccsid[] = "@(#)hash_conv.c	10.4 (Sleepycat) 9/15/97";
16 static const char sccsi2[] = "%W% (Sun) %G%";
17 #endif /* not lint */
18 
19 #ifndef NO_SYSTEM_INCLUDES
20 #include <sys/types.h>
21 #endif
22 
23 #include "db_int.h"
24 #include "db_page.h"
25 #include "db_swap.h"
26 #include "hash.h"
27 
28 /*
29  * __ham_pgin --
30  *	Convert host-specific page layout from the host-independent format
31  *	stored on disk.
32  *
33  * PUBLIC: int __ham_pgin __P((db_pgno_t, void *, DBT *));
34  */
35 int
__ham_pgin(pg,pp,cookie)36 __ham_pgin(pg, pp, cookie)
37 	db_pgno_t pg;
38 	void *pp;
39 	DBT *cookie;
40 {
41 	DB_PGINFO *pginfo;
42 	u_int32_t tpgno;
43 
44 	pginfo = (DB_PGINFO *)cookie->data;
45 	tpgno = PGNO((PAGE *)pp);
46 	if (pginfo->needswap)
47 		M_32_SWAP(tpgno);
48 
49 	if (pg != PGNO_METADATA && pg != tpgno) {
50 		P_INIT(pp, pginfo->db_pagesize,
51 		    pg, PGNO_INVALID, PGNO_INVALID, 0, P_HASH);
52 		return (0);
53 	}
54 
55 	if (!pginfo->needswap)
56 		return (0);
57 	return (pg == PGNO_METADATA ?
58 	    __ham_mswap(pp) : __db_pgin(pg, pginfo->db_pagesize, pp));
59 }
60 
61 /*
62  * __ham_pgout --
63  *	Convert host-specific page layout to the host-independent format
64  *	stored on disk.
65  *
66  * PUBLIC: int __ham_pgout __P((db_pgno_t, void *, DBT *));
67  */
68 int
__ham_pgout(pg,pp,cookie)69 __ham_pgout(pg, pp, cookie)
70 	db_pgno_t pg;
71 	void *pp;
72 	DBT *cookie;
73 {
74 	DB_PGINFO *pginfo;
75 
76 	pginfo = (DB_PGINFO *)cookie->data;
77 	if (!pginfo->needswap)
78 		return (0);
79 	return (pg == PGNO_METADATA ?
80 	    __ham_mswap(pp) : __db_pgout(pg, pginfo->db_pagesize, pp));
81 }
82 
83 /*
84  * __ham_mswap --
85  *	Swap the bytes on the hash metadata page.
86  *
87  * PUBLIC: int __ham_mswap __P((void *));
88  */
89 int
__ham_mswap(pg)90 __ham_mswap(pg)
91 	void *pg;
92 {
93 	u_int8_t *p;
94 	int i;
95 
96 	p = (u_int8_t *)pg;
97 	SWAP32(p);		/* lsn part 1 */
98 	SWAP32(p);		/* lsn part 2 */
99 	SWAP32(p);		/* pgno */
100 	SWAP32(p);		/* magic */
101 	SWAP32(p);		/* version */
102 	SWAP32(p);		/* pagesize */
103 	SWAP32(p);		/* ovfl_point */
104 	SWAP32(p);		/* last_freed */
105 	SWAP32(p);		/* max_bucket */
106 	SWAP32(p);		/* high_mask */
107 	SWAP32(p);		/* low_mask */
108 	SWAP32(p);		/* ffactor */
109 	SWAP32(p);		/* nelem */
110 	SWAP32(p);		/* h_charkey */
111 	SWAP32(p);		/* flags */
112 	for (i = 0; i < NCACHED; ++i)
113 		SWAP32(p);	/* spares */
114 	return (0);
115 }
116