xref: /NextBSD/sys/geom/geom_mbr_enc.c (revision eb1a5f8de9f7ea602c373a710f531abbf81141c4)
1 /*-
2  * Copyright (c) 2003 Poul-Henning Kamp
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /* Functions to encode or decode struct dos_partition into a bytestream
28  * of correct endianess and packing.  These functions do no validation
29  * or sanity checking, they only pack/unpack the fields correctly.
30  *
31  * NB!  This file must be usable both in kernel and userland.
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/types.h>
38 #include <sys/diskmbr.h>
39 #include <sys/endian.h>
40 
41 void
dos_partition_dec(void const * pp,struct dos_partition * d)42 dos_partition_dec(void const *pp, struct dos_partition *d)
43 {
44 	unsigned char const *p = pp;
45 
46 	d->dp_flag = p[0];
47 	d->dp_shd = p[1];
48 	d->dp_ssect = p[2];
49 	d->dp_scyl = p[3];
50 	d->dp_typ = p[4];
51 	d->dp_ehd = p[5];
52 	d->dp_esect = p[6];
53 	d->dp_ecyl = p[7];
54 	d->dp_start = le32dec(p + 8);
55 	d->dp_size = le32dec(p + 12);
56 }
57 
58 void
dos_partition_enc(void * pp,struct dos_partition * d)59 dos_partition_enc(void *pp, struct dos_partition *d)
60 {
61 	unsigned char *p = pp;
62 
63 	p[0] = d->dp_flag;
64 	p[1] = d->dp_shd;
65 	p[2] = d->dp_ssect;
66 	p[3] = d->dp_scyl;
67 	p[4] = d->dp_typ;
68 	p[5] = d->dp_ehd;
69 	p[6] = d->dp_esect;
70 	p[7] = d->dp_ecyl;
71 	le32enc(p + 8, d->dp_start);
72 	le32enc(p + 12, d->dp_size);
73 }
74