xref: /netbsd-src/lib/libc/gen/disklabel.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*
2  * Copyright (c) 1983, 1987 Regents of the University of California.
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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 /*static char *sccsid = "from: @(#)disklabel.c	5.17 (Berkeley) 2/23/91";*/
36 static char *rcsid = "$Id: disklabel.c,v 1.5 1994/06/12 22:52:01 cgd Exp $";
37 #endif /* LIBC_SCCS and not lint */
38 
39 #include <sys/param.h>
40 #include <sys/errno.h>
41 #include <ufs/ffs/fs.h>
42 #include <sys/file.h>
43 #define DKTYPENAMES
44 #include <sys/disklabel.h>
45 #include <stdio.h>
46 #include <string.h>
47 #include <stdlib.h>
48 #include <unistd.h>
49 
50 static char    *dgetstr();
51 static int	dgetent();
52 static int	dnamatch();
53 static int	dgetnum();
54 static int	dgetflag();
55 static int	gettype();
56 static void	error();
57 
58 struct disklabel *
59 getdiskbyname(name)
60 	const char *name;
61 {
62 	static struct	disklabel disk;
63 	static char 	boot[BUFSIZ];
64 	char	localbuf[BUFSIZ];
65 	char	buf[BUFSIZ];
66 	char	*cp, *cq;	/* can't be register */
67 	register struct	disklabel *dp = &disk;
68 	register struct partition *pp;
69 	char	p, max, psize[3], pbsize[3],
70 		pfsize[3], poffset[3], ptype[3];
71 	u_long	*dx;
72 
73 	if (dgetent(buf, name) <= 0)
74 		return ((struct disklabel *)0);
75 	bzero((char *)&disk, sizeof(disk));
76 	/*
77 	 * typename
78 	 */
79 	cq = dp->d_typename;
80 	cp = buf;
81 	while (cq < dp->d_typename + sizeof(dp->d_typename) - 1 &&
82 	    (*cq = *cp) && *cq != '|' && *cq != ':')
83 		cq++, cp++;
84 	*cq = '\0';
85 	/*
86 	 * boot name (optional)  xxboot, bootxx
87 	 */
88 	cp = boot;
89 	dp->d_boot0 = dgetstr("b0", &cp);
90 	dp->d_boot1 = dgetstr("b1", &cp);
91 	cp = localbuf;
92 	cq = dgetstr("ty", &cp);
93 	if (cq && strcmp(cq, "removable") == 0)
94 		dp->d_flags |= D_REMOVABLE;
95 	else  if (cq && strcmp(cq, "simulated") == 0)
96 		dp->d_flags |= D_RAMDISK;
97 	if (dgetflag("sf"))
98 		dp->d_flags |= D_BADSECT;
99 
100 #define getnumdflt(field, dname, dflt) \
101 	{ int f = dgetnum(dname); \
102 	(field) = f == -1 ? (dflt) : f; }
103 
104 	getnumdflt(dp->d_secsize, "se", DEV_BSIZE);
105 	dp->d_ntracks = dgetnum("nt");
106 	dp->d_nsectors = dgetnum("ns");
107 	dp->d_ncylinders = dgetnum("nc");
108 	cq = dgetstr("dt", &cp);
109 	if (cq)
110 		dp->d_type = gettype(cq, dktypenames);
111 	else
112 		getnumdflt(dp->d_type, "dt", 0);
113 	getnumdflt(dp->d_secpercyl, "sc", dp->d_nsectors * dp->d_ntracks);
114 	getnumdflt(dp->d_secperunit, "su", dp->d_secpercyl * dp->d_ncylinders);
115 	getnumdflt(dp->d_rpm, "rm", 3600);
116 	getnumdflt(dp->d_interleave, "il", 1);
117 	getnumdflt(dp->d_trackskew, "sk", 0);
118 	getnumdflt(dp->d_cylskew, "cs", 0);
119 	getnumdflt(dp->d_headswitch, "hs", 0);
120 	getnumdflt(dp->d_trkseek, "ts", 0);
121 	getnumdflt(dp->d_bbsize, "bs", BBSIZE);
122 	getnumdflt(dp->d_sbsize, "sb", SBSIZE);
123 	strcpy(psize, "px");
124 	strcpy(pbsize, "bx");
125 	strcpy(pfsize, "fx");
126 	strcpy(poffset, "ox");
127 	strcpy(ptype, "tx");
128 	max = 'a' - 1;
129 	pp = &dp->d_partitions[0];
130 	for (p = 'a'; p < 'a' + MAXPARTITIONS; p++, pp++) {
131 		psize[1] = pbsize[1] = pfsize[1] = poffset[1] = ptype[1] = p;
132 		pp->p_size = dgetnum(psize);
133 		if (pp->p_size == -1)
134 			pp->p_size = 0;
135 		else {
136 			pp->p_offset = dgetnum(poffset);
137 			getnumdflt(pp->p_fsize, pfsize, 0);
138 			if (pp->p_fsize)
139 				pp->p_frag = dgetnum(pbsize) / pp->p_fsize;
140 			getnumdflt(pp->p_fstype, ptype, 0);
141 			if (pp->p_fstype == 0 && (cq = dgetstr(ptype, &cp)))
142 				pp->p_fstype = gettype(cq, fstypenames);
143 			max = p;
144 		}
145 	}
146 	dp->d_npartitions = max + 1 - 'a';
147 	(void)strcpy(psize, "dx");
148 	dx = dp->d_drivedata;
149 	for (p = '0'; p < '0' + NDDATA; p++, dx++) {
150 		psize[1] = p;
151 		getnumdflt(*dx, psize, 0);
152 	}
153 	dp->d_magic = DISKMAGIC;
154 	dp->d_magic2 = DISKMAGIC;
155 	return (dp);
156 }
157 
158 #include <ctype.h>
159 
160 static	char *tbuf;
161 static	char *dskip();
162 static	char *ddecode();
163 
164 /*
165  * Get an entry for disk name in buffer bp,
166  * from the diskcap file.  Parse is very rudimentary;
167  * we just notice escaped newlines.
168  */
169 static int
170 dgetent(bp, name)
171 	char *bp, *name;
172 {
173 	register char *cp;
174 	register int c;
175 	register int i = 0, cnt = 0;
176 	char ibuf[BUFSIZ];
177 	int tf;
178 
179 	tbuf = bp;
180 	tf = open(_PATH_DISKTAB, 0);
181 	if (tf < 0) {
182 		error(errno);
183 		return (-1);
184 	}
185 	for (;;) {
186 		cp = bp;
187 		for (;;) {
188 			if (i == cnt) {
189 				cnt = read(tf, ibuf, BUFSIZ);
190 				if (cnt <= 0) {
191 					error(errno);
192 					close(tf);
193 					return (0);
194 				}
195 				i = 0;
196 			}
197 			c = ibuf[i++];
198 			if (c == '\n') {
199 				if (cp > bp && cp[-1] == '\\'){
200 					cp--;
201 					continue;
202 				}
203 				break;
204 			}
205 			if (cp >= bp+BUFSIZ) {
206 				error(EFTYPE);
207 				break;
208 			} else
209 				*cp++ = c;
210 		}
211 		*cp = 0;
212 
213 		/*
214 		 * The real work for the match.
215 		 */
216 		if (dnamatch(name)) {
217 			close(tf);
218 			return (1);
219 		}
220 	}
221 }
222 
223 /*
224  * Dnamatch deals with name matching.  The first field of the disktab
225  * entry is a sequence of names separated by |'s, so we compare
226  * against each such name.  The normal : terminator after the last
227  * name (before the first field) stops us.
228  */
229 static int
230 dnamatch(np)
231 	char *np;
232 {
233 	register char *Np, *Bp;
234 
235 	Bp = tbuf;
236 	if (*Bp == '#')
237 		return (0);
238 	for (;;) {
239 		for (Np = np; *Np && *Bp == *Np; Bp++, Np++)
240 			continue;
241 		if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0))
242 			return (1);
243 		while (*Bp && *Bp != ':' && *Bp != '|')
244 			Bp++;
245 		if (*Bp == 0 || *Bp == ':')
246 			return (0);
247 		Bp++;
248 	}
249 }
250 
251 /*
252  * Skip to the next field.  Notice that this is very dumb, not
253  * knowing about \: escapes or any such.  If necessary, :'s can be put
254  * into the diskcap file in octal.
255  */
256 static char *
257 dskip(bp)
258 	register char *bp;
259 {
260 
261 	while (*bp && *bp != ':')
262 		bp++;
263 	if (*bp == ':')
264 		bp++;
265 	return (bp);
266 }
267 
268 /*
269  * Return the (numeric) option id.
270  * Numeric options look like
271  *	li#80
272  * i.e. the option string is separated from the numeric value by
273  * a # character.  If the option is not found we return -1.
274  * Note that we handle octal numbers beginning with 0.
275  */
276 static int
277 dgetnum(id)
278 	char *id;
279 {
280 	register int i, base;
281 	register char *bp = tbuf;
282 
283 	for (;;) {
284 		bp = dskip(bp);
285 		if (*bp == 0)
286 			return (-1);
287 		if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
288 			continue;
289 		if (*bp == '@')
290 			return (-1);
291 		if (*bp != '#')
292 			continue;
293 		bp++;
294 		base = 10;
295 		if (*bp == '0')
296 			base = 8;
297 		i = 0;
298 		while (isdigit(*bp))
299 			i *= base, i += *bp++ - '0';
300 		return (i);
301 	}
302 }
303 
304 /*
305  * Handle a flag option.
306  * Flag options are given "naked", i.e. followed by a : or the end
307  * of the buffer.  Return 1 if we find the option, or 0 if it is
308  * not given.
309  */
310 static int
311 dgetflag(id)
312 	char *id;
313 {
314 	register char *bp = tbuf;
315 
316 	for (;;) {
317 		bp = dskip(bp);
318 		if (!*bp)
319 			return (0);
320 		if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) {
321 			if (!*bp || *bp == ':')
322 				return (1);
323 			else if (*bp == '@')
324 				return (0);
325 		}
326 	}
327 }
328 
329 /*
330  * Get a string valued option.
331  * These are given as
332  *	cl=^Z
333  * Much decoding is done on the strings, and the strings are
334  * placed in area, which is a ref parameter which is updated.
335  * No checking on area overflow.
336  */
337 static char *
338 dgetstr(id, area)
339 	char *id, **area;
340 {
341 	register char *bp = tbuf;
342 
343 	for (;;) {
344 		bp = dskip(bp);
345 		if (!*bp)
346 			return (0);
347 		if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1])
348 			continue;
349 		if (*bp == '@')
350 			return (0);
351 		if (*bp != '=')
352 			continue;
353 		bp++;
354 		return (ddecode(bp, area));
355 	}
356 }
357 
358 /*
359  * Tdecode does the grung work to decode the
360  * string capability escapes.
361  */
362 static char *
363 ddecode(str, area)
364 	register char *str;
365 	char **area;
366 {
367 	register char *cp;
368 	register int c;
369 	register char *dp;
370 	int i;
371 
372 	cp = *area;
373 	while ((c = *str++) && c != ':') {
374 		switch (c) {
375 
376 		case '^':
377 			c = *str++ & 037;
378 			break;
379 
380 		case '\\':
381 			dp = "E\033^^\\\\::n\nr\rt\tb\bf\f";
382 			c = *str++;
383 nextc:
384 			if (*dp++ == c) {
385 				c = *dp++;
386 				break;
387 			}
388 			dp++;
389 			if (*dp)
390 				goto nextc;
391 			if (isdigit(c)) {
392 				c -= '0', i = 2;
393 				do
394 					c <<= 3, c |= *str++ - '0';
395 				while (--i && isdigit(*str));
396 			}
397 			break;
398 		}
399 		*cp++ = c;
400 	}
401 	*cp++ = 0;
402 	str = *area;
403 	*area = cp;
404 	return (str);
405 }
406 
407 static int
408 gettype(t, names)
409 	char *t;
410 	char **names;
411 {
412 	register char **nm;
413 
414 	for (nm = names; *nm; nm++)
415 		if (strcasecmp(t, *nm) == 0)
416 			return (nm - names);
417 	if (isdigit(*t))
418 		return (atoi(t));
419 	return (0);
420 }
421 
422 static void
423 error(err)
424 	int err;
425 {
426 	char *p;
427 
428 	(void)write(STDERR_FILENO, "disktab: ", 9);
429 	(void)write(STDERR_FILENO, _PATH_DISKTAB, sizeof(_PATH_DISKTAB) - 1);
430 	p = strerror(err);
431 	(void)write(STDERR_FILENO, p, strlen(p));
432 	(void)write(STDERR_FILENO, "\n", 1);
433 }
434