xref: /openbsd/lib/libc/gen/disklabel.c (revision c0a65584)
1 /*
2  * Copyright (c) 1983, 1987, 1993
3  *	The Regents of the University of California.  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  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/param.h>	/* DEV_BSIZE */
31 #include <sys/types.h>
32 #define DKTYPENAMES
33 #include <sys/disklabel.h>
34 #include <ufs/ffs/fs.h>
35 
36 #include <ctype.h>
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <limits.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 static u_int	gettype(char *, const char * const *);
46 
47 struct disklabel *
getdiskbyname(const char * name)48 getdiskbyname(const char *name)
49 {
50 	static struct	disklabel disk;
51 	struct	disklabel *dp = &disk;
52 	struct partition *pp;
53 	char	*buf;
54 	char	*db_array[2] = { _PATH_DISKTAB, 0 };
55 	char	*cp, *cq;
56 	char	p, max, psize[3], pbsize[3],
57 		pfsize[3], poffset[3], ptype[3];
58 
59 	if (cgetent(&buf, db_array, (char *) name) < 0)
60 		return NULL;
61 
62 	bzero((char *)&disk, sizeof(disk));
63 	/*
64 	 * typename
65 	 */
66 	cq = dp->d_typename;
67 	cp = buf;
68 	while (cq < dp->d_typename + sizeof(dp->d_typename) - 1 &&
69 	    (*cq = *cp) && *cq != '|' && *cq != ':')
70 		cq++, cp++;
71 	*cq = '\0';
72 
73 #define getnumdflt(field, dname, dflt) \
74 	{ long f; (field) = (cgetnum(buf, dname, &f) == -1) ? (dflt) : f; }
75 #define	getnum(field, dname) \
76 	{ long f; cgetnum(buf, dname, &f); field = f; }
77 
78 	getnumdflt(dp->d_secsize, "se", DEV_BSIZE);
79 	getnum(dp->d_ntracks, "nt");
80 	getnum(dp->d_nsectors, "ns");
81 	getnum(dp->d_ncylinders, "nc");
82 
83 	if (cgetstr(buf, "dt", &cq) > 0)
84 		dp->d_type = (u_short)gettype(cq, dktypenames);
85 	else
86 		getnumdflt(dp->d_type, "dt", 0);
87 	getnumdflt(dp->d_secpercyl, "sc", dp->d_nsectors * dp->d_ntracks);
88 	/* XXX */
89 	dp->d_secperunith = 0;
90 	getnumdflt(dp->d_secperunit, "su", dp->d_secpercyl * dp->d_ncylinders);
91 	strlcpy(psize, "px", sizeof psize);
92 	strlcpy(pbsize, "bx", sizeof pbsize);
93 	strlcpy(pfsize, "fx", sizeof pfsize);
94 	strlcpy(poffset, "ox", sizeof poffset);
95 	strlcpy(ptype, "tx", sizeof ptype);
96 	max = 'a' - 1;
97 	pp = &dp->d_partitions[0];
98 	dp->d_version = 1;
99 	for (p = 'a'; p < 'a' + MAXPARTITIONS; p++, pp++) {
100 		long f;
101 
102 		psize[1] = pbsize[1] = pfsize[1] = poffset[1] = ptype[1] = p;
103 		/* XXX */
104 		if (cgetnum(buf, psize, &f) == -1)
105 			DL_SETPSIZE(pp, 0);
106 		else {
107 			u_int32_t fsize, frag = 8;
108 
109 			DL_SETPSIZE(pp, f);
110 			/* XXX */
111 			pp->p_offseth = 0;
112 			getnum(pp->p_offset, poffset);
113 			getnumdflt(fsize, pfsize, 0);
114 			if (fsize) {
115 				long bsize;
116 
117 				if (cgetnum(buf, pbsize, &bsize) == 0)
118 					frag = bsize / fsize;
119 				pp->p_fragblock =
120 				    DISKLABELV1_FFS_FRAGBLOCK(fsize, frag);
121 			}
122 			getnumdflt(pp->p_fstype, ptype, 0);
123 			if (pp->p_fstype == 0 && cgetstr(buf, ptype, &cq) > 0)
124 				pp->p_fstype = (u_char)gettype(cq, fstypenames);
125 			max = p;
126 		}
127 	}
128 	dp->d_npartitions = max + 1 - 'a';
129 	dp->d_magic = DISKMAGIC;
130 	dp->d_magic2 = DISKMAGIC;
131 	free(buf);
132 	return (dp);
133 }
134 
135 static u_int
gettype(char * t,const char * const * names)136 gettype(char *t, const char * const *names)
137 {
138 	const char * const *nm;
139 
140 	for (nm = names; *nm; nm++)
141 		if (strcasecmp(t, *nm) == 0)
142 			return (nm - names);
143 	if (isdigit((u_char)*t))
144 		return ((u_int)strtonum(t, 0, USHRT_MAX, NULL));
145 	return (0);
146 }
147