1 /* 2 * Copyright (c) 1983,1987 Regents of the University of California. 3 * All rights reserved. The Berkeley software License Agreement 4 * specifies the terms and conditions for redistribution. 5 */ 6 7 #if defined(LIBC_SCCS) && !defined(lint) 8 static char sccsid[] = "@(#)disklabel.c 5.7 (Berkeley) 03/28/87"; 9 #endif LIBC_SCCS and not lint 10 11 #include <sys/param.h> 12 #include <sys/fs.h> 13 #include <sys/file.h> 14 #define DKTYPENAMES 15 #include <sys/disklabel.h> 16 #include <stdio.h> 17 #include <strings.h> 18 19 static char *dgetstr(); 20 21 struct disklabel * 22 getdiskbyname(name) 23 char *name; 24 { 25 static struct disklabel disk; 26 static char localbuf[100]; 27 char *cp, *cq; 28 register struct disklabel *dp = &disk; 29 register struct partition *pp; 30 char p, max, psize[3], pbsize[3], pfsize[3], poffset[3], ptype[3]; 31 char buf[BUFSIZ]; 32 u_long *dx; 33 34 if (dgetent(buf, name) <= 0) 35 return ((struct disklabel *)0); 36 bzero((char *)&disk, sizeof(disk)); 37 cq = dp->d_typename; 38 cp = buf; 39 while (cq < dp->d_typename + sizeof(dp->d_typename) - 1 && 40 (*cq = *cp) && *cq != '|' && *cq != ':') 41 cq++, cp++; 42 *cq = '\0'; 43 cp = localbuf; 44 cq = dgetstr("ty", &cp); 45 if (cq && strcmp(cq, "removable") == 0) 46 dp->d_flags |= D_REMOVABLE; 47 else if (cq && strcmp(cq, "simulated") == 0) 48 dp->d_flags |= D_RAMDISK; 49 if (dgetflag("sf")) 50 dp->d_flags |= D_BADSECT; 51 #define getnumdflt(field, dname, dflt) \ 52 { int f = dgetnum(dname); \ 53 (field) = f == -1 ? (dflt) : f; } 54 55 getnumdflt(dp->d_secsize, "se", DEV_BSIZE); 56 dp->d_ntracks = dgetnum("nt"); 57 dp->d_nsectors = dgetnum("ns"); 58 dp->d_ncylinders = dgetnum("nc"); 59 cq = dgetstr("dt", &cp); 60 if (cq) 61 dp->d_type = gettype(cq, dktypenames); 62 else 63 getnumdflt(dp->d_type, "dt", 0); 64 getnumdflt(dp->d_secpercyl, "sc", dp->d_nsectors * dp->d_ntracks); 65 getnumdflt(dp->d_secperunit, "su", dp->d_secpercyl * dp->d_ncylinders); 66 getnumdflt(dp->d_rpm, "rm", 3600); 67 getnumdflt(dp->d_interleave, "il", 1); 68 getnumdflt(dp->d_trackskew, "sk", 0); 69 getnumdflt(dp->d_cylskew, "cs", 0); 70 getnumdflt(dp->d_headswitch, "hs", 0); 71 getnumdflt(dp->d_trkseek, "ts", 0); 72 getnumdflt(dp->d_bbsize, "bs", BBSIZE); 73 getnumdflt(dp->d_sbsize, "sb", SBSIZE); 74 strcpy(psize, "px"); 75 strcpy(pbsize, "bx"); 76 strcpy(pfsize, "fx"); 77 strcpy(poffset, "ox"); 78 strcpy(ptype, "tx"); 79 max = 'a' - 1; 80 pp = &dp->d_partitions[0]; 81 for (p = 'a'; p < 'a' + MAXPARTITIONS; p++, pp++) { 82 psize[1] = pbsize[1] = pfsize[1] = poffset[1] = ptype[1] = p; 83 pp->p_size = dgetnum(psize); 84 if (pp->p_size == -1) 85 pp->p_size = 0; 86 else { 87 pp->p_offset = dgetnum(poffset); 88 getnumdflt(pp->p_fsize, pfsize, 0); 89 if (pp->p_fsize) 90 pp->p_frag = dgetnum(pbsize) / pp->p_fsize; 91 getnumdflt(pp->p_fstype, ptype, 0); 92 if (pp->p_fstype == 0 && (cq = dgetstr(ptype, &cp))) 93 pp->p_fstype = gettype(cq, fstypenames); 94 max = p; 95 } 96 } 97 dp->d_npartitions = max + 1 - 'a'; 98 (void)strcpy(psize, "dx"); 99 dx = dp->d_drivedata; 100 for (p = '0'; p < '0' + NDDATA; p++, dx++) { 101 psize[1] = p; 102 getnumdflt(*dx, psize, 0); 103 } 104 dp->d_magic = DISKMAGIC; 105 dp->d_magic2 = DISKMAGIC; 106 return (dp); 107 } 108 109 #include <ctype.h> 110 111 static char *tbuf; 112 static char *dskip(); 113 static char *ddecode(); 114 115 /* 116 * Get an entry for disk name in buffer bp, 117 * from the diskcap file. Parse is very rudimentary; 118 * we just notice escaped newlines. 119 */ 120 static 121 dgetent(bp, name) 122 char *bp, *name; 123 { 124 register char *cp; 125 register int c; 126 register int i = 0, cnt = 0; 127 char ibuf[BUFSIZ]; 128 int tf; 129 130 tbuf = bp; 131 tf = open(DISKTAB, 0); 132 if (tf < 0) 133 return (-1); 134 for (;;) { 135 cp = bp; 136 for (;;) { 137 if (i == cnt) { 138 cnt = read(tf, ibuf, BUFSIZ); 139 if (cnt <= 0) { 140 close(tf); 141 return (0); 142 } 143 i = 0; 144 } 145 c = ibuf[i++]; 146 if (c == '\n') { 147 if (cp > bp && cp[-1] == '\\'){ 148 cp--; 149 continue; 150 } 151 break; 152 } 153 if (cp >= bp+BUFSIZ) { 154 write(2,"Disktab entry too long\n", 23); 155 break; 156 } else 157 *cp++ = c; 158 } 159 *cp = 0; 160 161 /* 162 * The real work for the match. 163 */ 164 if (dnamatch(name)) { 165 close(tf); 166 return (1); 167 } 168 } 169 } 170 171 /* 172 * Dnamatch deals with name matching. The first field of the disktab 173 * entry is a sequence of names separated by |'s, so we compare 174 * against each such name. The normal : terminator after the last 175 * name (before the first field) stops us. 176 */ 177 static 178 dnamatch(np) 179 char *np; 180 { 181 register char *Np, *Bp; 182 183 Bp = tbuf; 184 if (*Bp == '#') 185 return (0); 186 for (;;) { 187 for (Np = np; *Np && *Bp == *Np; Bp++, Np++) 188 continue; 189 if (*Np == 0 && (*Bp == '|' || *Bp == ':' || *Bp == 0)) 190 return (1); 191 while (*Bp && *Bp != ':' && *Bp != '|') 192 Bp++; 193 if (*Bp == 0 || *Bp == ':') 194 return (0); 195 Bp++; 196 } 197 } 198 199 /* 200 * Skip to the next field. Notice that this is very dumb, not 201 * knowing about \: escapes or any such. If necessary, :'s can be put 202 * into the diskcap file in octal. 203 */ 204 static char * 205 dskip(bp) 206 register char *bp; 207 { 208 209 while (*bp && *bp != ':') 210 bp++; 211 if (*bp == ':') 212 bp++; 213 return (bp); 214 } 215 216 /* 217 * Return the (numeric) option id. 218 * Numeric options look like 219 * li#80 220 * i.e. the option string is separated from the numeric value by 221 * a # character. If the option is not found we return -1. 222 * Note that we handle octal numbers beginning with 0. 223 */ 224 static 225 dgetnum(id) 226 char *id; 227 { 228 register int i, base; 229 register char *bp = tbuf; 230 231 for (;;) { 232 bp = dskip(bp); 233 if (*bp == 0) 234 return (-1); 235 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1]) 236 continue; 237 if (*bp == '@') 238 return (-1); 239 if (*bp != '#') 240 continue; 241 bp++; 242 base = 10; 243 if (*bp == '0') 244 base = 8; 245 i = 0; 246 while (isdigit(*bp)) 247 i *= base, i += *bp++ - '0'; 248 return (i); 249 } 250 } 251 252 /* 253 * Handle a flag option. 254 * Flag options are given "naked", i.e. followed by a : or the end 255 * of the buffer. Return 1 if we find the option, or 0 if it is 256 * not given. 257 */ 258 static 259 dgetflag(id) 260 char *id; 261 { 262 register char *bp = tbuf; 263 264 for (;;) { 265 bp = dskip(bp); 266 if (!*bp) 267 return (0); 268 if (*bp++ == id[0] && *bp != 0 && *bp++ == id[1]) { 269 if (!*bp || *bp == ':') 270 return (1); 271 else if (*bp == '@') 272 return (0); 273 } 274 } 275 } 276 277 /* 278 * Get a string valued option. 279 * These are given as 280 * cl=^Z 281 * Much decoding is done on the strings, and the strings are 282 * placed in area, which is a ref parameter which is updated. 283 * No checking on area overflow. 284 */ 285 static char * 286 dgetstr(id, area) 287 char *id, **area; 288 { 289 register char *bp = tbuf; 290 291 for (;;) { 292 bp = dskip(bp); 293 if (!*bp) 294 return (0); 295 if (*bp++ != id[0] || *bp == 0 || *bp++ != id[1]) 296 continue; 297 if (*bp == '@') 298 return (0); 299 if (*bp != '=') 300 continue; 301 bp++; 302 return (ddecode(bp, area)); 303 } 304 } 305 306 /* 307 * Tdecode does the grung work to decode the 308 * string capability escapes. 309 */ 310 static char * 311 ddecode(str, area) 312 register char *str; 313 char **area; 314 { 315 register char *cp; 316 register int c; 317 register char *dp; 318 int i; 319 320 cp = *area; 321 while ((c = *str++) && c != ':') { 322 switch (c) { 323 324 case '^': 325 c = *str++ & 037; 326 break; 327 328 case '\\': 329 dp = "E\033^^\\\\::n\nr\rt\tb\bf\f"; 330 c = *str++; 331 nextc: 332 if (*dp++ == c) { 333 c = *dp++; 334 break; 335 } 336 dp++; 337 if (*dp) 338 goto nextc; 339 if (isdigit(c)) { 340 c -= '0', i = 2; 341 do 342 c <<= 3, c |= *str++ - '0'; 343 while (--i && isdigit(*str)); 344 } 345 break; 346 } 347 *cp++ = c; 348 } 349 *cp++ = 0; 350 str = *area; 351 *area = cp; 352 return (str); 353 } 354 355 static 356 gettype(t, names) 357 char *t; 358 char **names; 359 { 360 register char **nm; 361 362 for (nm = names; *nm; nm++) 363 if (ustrcmp(t, *nm) == 0) 364 return (nm - names); 365 if (isdigit(*t)) 366 return (atoi(t)); 367 return (0); 368 } 369 370 static 371 ustrcmp(s1, s2) 372 register char *s1, *s2; 373 { 374 #define lower(c) (islower(c) ? (c) : tolower(c)) 375 376 for (; *s1; s1++, s2++) { 377 if (*s1 == *s2) 378 continue; 379 if (isalpha(*s1) && isalpha(*s2) && 380 lower(*s1) == lower(*s2)) 381 continue; 382 return (*s2 - *s1); 383 } 384 return (0); 385 } 386 387 dkcksum(lp) 388 register struct disklabel *lp; 389 { 390 register u_short *start, *end; 391 register u_short sum = 0; 392 393 start = (u_short *)lp; 394 end = (u_short *)&lp->d_partitions[lp->d_npartitions]; 395 while (start < end) 396 sum ^= *start++; 397 return (sum); 398 } 399