| 1 | /* sys.c 4.4 81/03/22 */ |
| 2 | |
| 3 | #include <sys/param.h> |
| 4 | #include <sys/ino.h> |
| 5 | #include <sys/inode.h> |
| 6 | #include <sys/filsys.h> |
| 7 | #include <sys/dir.h> |
| 8 | #include "saio.h" |
| 9 | |
| 10 | ino_t dlook(); |
| 11 | |
| 12 | static |
| 13 | openi(n,io) |
| 14 | register struct iob *io; |
| 15 | { |
| 16 | register struct dinode *dp; |
| 17 | |
| 18 | io->i_offset = 0; |
| 19 | io->i_bn = fsbtodb(itod(n)) + io->i_boff; |
| 20 | io->i_cc = BSIZE; |
| 21 | io->i_ma = io->i_buf; |
| 22 | devread(io); |
| 23 | |
| 24 | dp = (struct dinode *)io->i_buf; |
| 25 | dp = &dp[itoo(n)]; |
| 26 | io->i_ino.i_number = n; |
| 27 | io->i_ino.i_mode = dp->di_mode; |
| 28 | io->i_ino.i_size = dp->di_size; |
| 29 | l3tol((char *)io->i_ino.i_un.i_addr, (char *)dp->di_addr, NADDR); |
| 30 | } |
| 31 | |
| 32 | static |
| 33 | find(path, file) |
| 34 | register char *path; |
| 35 | struct iob *file; |
| 36 | { |
| 37 | register char *q; |
| 38 | char c; |
| 39 | int n; |
| 40 | |
| 41 | if (path==NULL || *path=='\0') { |
| 42 | printf("null path\n"); |
| 43 | return(0); |
| 44 | } |
| 45 | |
| 46 | openi((ino_t) ROOTINO, file); |
| 47 | while (*path) { |
| 48 | while (*path == '/') |
| 49 | path++; |
| 50 | q = path; |
| 51 | while(*q != '/' && *q != '\0') |
| 52 | q++; |
| 53 | c = *q; |
| 54 | *q = '\0'; |
| 55 | |
| 56 | if ((n=dlook(path, file))!=0) { |
| 57 | if (c=='\0') |
| 58 | break; |
| 59 | openi(n, file); |
| 60 | *q = c; |
| 61 | path = q; |
| 62 | continue; |
| 63 | } else { |
| 64 | printf("%s not found\n",path); |
| 65 | return(0); |
| 66 | } |
| 67 | } |
| 68 | return(n); |
| 69 | } |
| 70 | |
| 71 | static daddr_t |
| 72 | sbmap(io, bn) |
| 73 | register struct iob *io; |
| 74 | daddr_t bn; |
| 75 | { |
| 76 | register i; |
| 77 | register struct inode *ip; |
| 78 | int j, sh; |
| 79 | daddr_t nb, *bap; |
| 80 | int ibn = bn; |
| 81 | |
| 82 | ip = &io->i_ino; |
| 83 | if(bn < 0) { |
| 84 | printf("bn negative\n"); |
| 85 | return((daddr_t)0); |
| 86 | } |
| 87 | |
| 88 | /* |
| 89 | * blocks 0..NADDR-4 are direct blocks |
| 90 | */ |
| 91 | if(bn < NADDR-3) { |
| 92 | i = bn; |
| 93 | nb = ip->i_un.i_addr[i]; |
| 94 | return(nb); |
| 95 | } |
| 96 | |
| 97 | /* |
| 98 | * addresses NADDR-3, NADDR-2, and NADDR-1 |
| 99 | * have single, double, triple indirect blocks. |
| 100 | * the first step is to determine |
| 101 | * how many levels of indirection. |
| 102 | */ |
| 103 | sh = 0; |
| 104 | nb = 1; |
| 105 | bn -= NADDR-3; |
| 106 | for(j=3; j>0; j--) { |
| 107 | sh += NSHIFT; |
| 108 | nb <<= NSHIFT; |
| 109 | if(bn < nb) |
| 110 | break; |
| 111 | bn -= nb; |
| 112 | } |
| 113 | if(j == 0) { |
| 114 | printf("bn ovf %D\n",bn); |
| 115 | return((daddr_t)0); |
| 116 | } |
| 117 | |
| 118 | /* |
| 119 | * fetch the address from the inode |
| 120 | */ |
| 121 | nb = ip->i_un.i_addr[NADDR-j]; |
| 122 | if(nb == 0) { |
| 123 | printf("bn void %D\n",bn); |
| 124 | return((daddr_t)0); |
| 125 | } |
| 126 | |
| 127 | /* |
| 128 | * fetch through the indirect blocks |
| 129 | */ |
| 130 | for(; j<=3; j++) { |
| 131 | if (blknos[j] != nb) { |
| 132 | io->i_bn = fsbtodb(nb) + io->i_boff; |
| 133 | io->i_ma = b[j]; |
| 134 | io->i_cc = BSIZE; |
| 135 | devread(io); |
| 136 | bap = (daddr_t *)b[j]; |
| 137 | blknos[j] = nb; |
| 138 | } |
| 139 | bap = (daddr_t *)b[j]; |
| 140 | sh -= NSHIFT; |
| 141 | i = (bn>>sh) & NMASK; |
| 142 | nb = bap[i]; |
| 143 | if(nb == 0) { |
| 144 | printf("bn void %D\n",bn); |
| 145 | return((daddr_t)0); |
| 146 | } |
| 147 | } |
| 148 | return(nb); |
| 149 | } |
| 150 | |
| 151 | static ino_t |
| 152 | dlook(s, io) |
| 153 | char *s; |
| 154 | register struct iob *io; |
| 155 | { |
| 156 | register struct direct *dp; |
| 157 | register struct inode *ip; |
| 158 | daddr_t bn; |
| 159 | int n,dc; |
| 160 | |
| 161 | if (s==NULL || *s=='\0') |
| 162 | return(0); |
| 163 | ip = &io->i_ino; |
| 164 | if ((ip->i_mode&IFMT)!=IFDIR) { |
| 165 | printf("not a directory\n"); |
| 166 | return(0); |
| 167 | } |
| 168 | |
| 169 | n = ip->i_size/sizeof(struct direct); |
| 170 | |
| 171 | if (n==0) { |
| 172 | printf("zero length directory\n"); |
| 173 | return(0); |
| 174 | } |
| 175 | |
| 176 | dc = BSIZE; |
| 177 | bn = (daddr_t)0; |
| 178 | while(n--) { |
| 179 | if (++dc >= BSIZE/sizeof(struct direct)) { |
| 180 | io->i_bn = fsbtodb(sbmap(io, bn++)) + io->i_boff; |
| 181 | io->i_ma = io->i_buf; |
| 182 | io->i_cc = BSIZE; |
| 183 | devread(io); |
| 184 | dp = (struct direct *)io->i_buf; |
| 185 | dc = 0; |
| 186 | } |
| 187 | |
| 188 | if (match(s, dp->d_name)) |
| 189 | return(dp->d_ino); |
| 190 | dp++; |
| 191 | } |
| 192 | return(0); |
| 193 | } |
| 194 | |
| 195 | static |
| 196 | match(s1,s2) |
| 197 | register char *s1,*s2; |
| 198 | { |
| 199 | register cc; |
| 200 | |
| 201 | cc = DIRSIZ; |
| 202 | while (cc--) { |
| 203 | if (*s1 != *s2) |
| 204 | return(0); |
| 205 | if (*s1++ && *s2++) |
| 206 | continue; else |
| 207 | return(1); |
| 208 | } |
| 209 | return(1); |
| 210 | } |
| 211 | |
| 212 | lseek(fdesc, addr, ptr) |
| 213 | int fdesc; |
| 214 | off_t addr; |
| 215 | int ptr; |
| 216 | { |
| 217 | register struct iob *io; |
| 218 | |
| 219 | if (ptr != 0) { |
| 220 | printf("Seek not from beginning of file\n"); |
| 221 | return(-1); |
| 222 | } |
| 223 | fdesc -= 3; |
| 224 | if (fdesc < 0 || fdesc >= NFILES || ((io = &iob[fdesc])->i_flgs&F_ALLOC) == 0) |
| 225 | return(-1); |
| 226 | io->i_offset = addr; |
| 227 | io->i_bn = fsbtodb(addr/BSIZE) + io->i_boff; |
| 228 | io->i_cc = 0; |
| 229 | return(0); |
| 230 | } |
| 231 | |
| 232 | getc(fdesc) |
| 233 | int fdesc; |
| 234 | { |
| 235 | register struct iob *io; |
| 236 | register char *p; |
| 237 | register c; |
| 238 | int off; |
| 239 | |
| 240 | |
| 241 | if (fdesc >= 0 && fdesc <= 2) |
| 242 | return(getchar()); |
| 243 | fdesc -= 3; |
| 244 | if (fdesc < 0 || fdesc >= NFILES || ((io = &iob[fdesc])->i_flgs&F_ALLOC) == 0) |
| 245 | return(-1); |
| 246 | p = io->i_ma; |
| 247 | if (io->i_cc <= 0) { |
| 248 | io->i_bn = fsbtodb(io->i_offset/(off_t)BSIZE); |
| 249 | if (io->i_flgs&F_FILE) |
| 250 | io->i_bn = fsbtodb(sbmap(io, dbtofsb(io->i_bn))) + io->i_boff; |
| 251 | io->i_ma = io->i_buf; |
| 252 | io->i_cc = BSIZE; |
| 253 | devread(io); |
| 254 | if (io->i_flgs&F_FILE) { |
| 255 | off = io->i_offset % (off_t)BSIZE; |
| 256 | if (io->i_offset+(BSIZE-off) >= io->i_ino.i_size) |
| 257 | io->i_cc = io->i_ino.i_size - io->i_offset + off; |
| 258 | io->i_cc -= off; |
| 259 | if (io->i_cc <= 0) |
| 260 | return(-1); |
| 261 | } else |
| 262 | off = 0; |
| 263 | p = &io->i_buf[off]; |
| 264 | } |
| 265 | io->i_cc--; |
| 266 | io->i_offset++; |
| 267 | c = (unsigned)*p++; |
| 268 | io->i_ma = p; |
| 269 | return(c); |
| 270 | } |
| 271 | /* does this port? |
| 272 | getw(fdesc) |
| 273 | int fdesc; |
| 274 | { |
| 275 | register w,i; |
| 276 | register char *cp; |
| 277 | int val; |
| 278 | |
| 279 | for (i = 0, val = 0, cp = &val; i < sizeof(val); i++) { |
| 280 | w = getc(fdesc); |
| 281 | if (w < 0) { |
| 282 | if (i == 0) |
| 283 | return(-1); |
| 284 | else |
| 285 | return(val); |
| 286 | } |
| 287 | *cp++ = w; |
| 288 | } |
| 289 | return(val); |
| 290 | } |
| 291 | */ |
| 292 | |
| 293 | read(fdesc, buf, count) |
| 294 | int fdesc; |
| 295 | char *buf; |
| 296 | int count; |
| 297 | { |
| 298 | register i; |
| 299 | register struct iob *file; |
| 300 | |
| 301 | if (fdesc >= 0 & fdesc <= 2) { |
| 302 | i = count; |
| 303 | do { |
| 304 | *buf = getchar(); |
| 305 | } while (--i && *buf++ != '\n'); |
| 306 | return(count - i); |
| 307 | } |
| 308 | fdesc -= 3; |
| 309 | if (fdesc < 0 || fdesc >= NFILES || ((file = &iob[fdesc])->i_flgs&F_ALLOC) == 0) |
| 310 | return(-1); |
| 311 | if ((file->i_flgs&F_READ) == 0) |
| 312 | return(-1); |
| 313 | if ((file->i_flgs&F_FILE) == 0) { |
| 314 | file->i_cc = count; |
| 315 | file->i_ma = buf; |
| 316 | i = devread(file); |
| 317 | file->i_bn += CLSIZE; |
| 318 | return(i); |
| 319 | } |
| 320 | else { |
| 321 | if (file->i_offset+count > file->i_ino.i_size) |
| 322 | count = file->i_ino.i_size - file->i_offset; |
| 323 | if ((i = count) <= 0) |
| 324 | return(0); |
| 325 | do { |
| 326 | *buf++ = getc(fdesc+3); |
| 327 | } while (--i); |
| 328 | return(count); |
| 329 | } |
| 330 | } |
| 331 | |
| 332 | write(fdesc, buf, count) |
| 333 | int fdesc; |
| 334 | char *buf; |
| 335 | int count; |
| 336 | { |
| 337 | register i; |
| 338 | register struct iob *file; |
| 339 | |
| 340 | if (fdesc >= 0 && fdesc <= 2) { |
| 341 | i = count; |
| 342 | while (i--) |
| 343 | putchar(*buf++); |
| 344 | return(count); |
| 345 | } |
| 346 | fdesc -= 3; |
| 347 | if (fdesc < 0 || fdesc >= NFILES || ((file = &iob[fdesc])->i_flgs&F_ALLOC) == 0) |
| 348 | return(-1); |
| 349 | if ((file->i_flgs&F_WRITE) == 0) |
| 350 | return(-1); |
| 351 | file->i_cc = count; |
| 352 | file->i_ma = buf; |
| 353 | i = devwrite(file); |
| 354 | file->i_bn += CLSIZE; |
| 355 | return(i); |
| 356 | } |
| 357 | |
| 358 | int openfirst = 1; |
| 359 | |
| 360 | open(str, how) |
| 361 | char *str; |
| 362 | int how; |
| 363 | { |
| 364 | register char *cp; |
| 365 | int i; |
| 366 | register struct iob *file; |
| 367 | register struct devsw *dp; |
| 368 | int fdesc; |
| 369 | long atol(); |
| 370 | |
| 371 | if (openfirst) { |
| 372 | for (i = 0; i < NFILES; i++) |
| 373 | iob[i].i_flgs = 0; |
| 374 | openfirst = 0; |
| 375 | } |
| 376 | |
| 377 | for (fdesc = 0; fdesc < NFILES; fdesc++) |
| 378 | if (iob[fdesc].i_flgs == 0) |
| 379 | goto gotfile; |
| 380 | _stop("No more file slots"); |
| 381 | gotfile: |
| 382 | (file = &iob[fdesc])->i_flgs |= F_ALLOC; |
| 383 | |
| 384 | for (cp = str; *cp && *cp != '('; cp++) |
| 385 | ; |
| 386 | if (*cp != '(') { |
| 387 | printf("Bad device\n"); |
| 388 | file->i_flgs = 0; |
| 389 | return(-1); |
| 390 | } |
| 391 | *cp++ = '\0'; |
| 392 | for (dp = devsw; dp->dv_name; dp++) { |
| 393 | if (match(str, dp->dv_name)) |
| 394 | goto gotdev; |
| 395 | } |
| 396 | printf("Unknown device\n"); |
| 397 | file->i_flgs = 0; |
| 398 | return(-1); |
| 399 | gotdev: |
| 400 | *(cp-1) = '('; |
| 401 | file->i_ino.i_dev = dp-devsw; |
| 402 | file->i_unit = *cp++ - '0'; |
| 403 | if (*cp >= '0' && *cp <= '9') |
| 404 | file->i_unit = file->i_unit * 10 + *cp++ - '0'; |
| 405 | if (file->i_unit < 0 || file->i_unit > 31) { |
| 406 | printf("Bad unit specifier\n"); |
| 407 | file->i_flgs = 0; |
| 408 | return(-1); |
| 409 | } |
| 410 | if (*cp++ != ',') { |
| 411 | badoff: |
| 412 | printf("Missing offset specification\n"); |
| 413 | file->i_flgs = 0; |
| 414 | return(-1); |
| 415 | } |
| 416 | file->i_boff = atol(cp); |
| 417 | for (;;) { |
| 418 | if (*cp == ')') |
| 419 | break; |
| 420 | if (*cp++) |
| 421 | continue; |
| 422 | goto badoff; |
| 423 | } |
| 424 | devopen(file); |
| 425 | if (*++cp == '\0') { |
| 426 | file->i_flgs |= how+1; |
| 427 | file->i_cc = 0; |
| 428 | file->i_offset = 0; |
| 429 | return(fdesc+3); |
| 430 | } |
| 431 | if ((i = find(cp, file)) == 0) { |
| 432 | file->i_flgs = 0; |
| 433 | return(-1); |
| 434 | } |
| 435 | if (how != 0) { |
| 436 | printf("Can't write files yet.. Sorry\n"); |
| 437 | file->i_flgs = 0; |
| 438 | return(-1); |
| 439 | } |
| 440 | openi(i, file); |
| 441 | file->i_offset = 0; |
| 442 | file->i_cc = 0; |
| 443 | file->i_flgs |= F_FILE | (how+1); |
| 444 | return(fdesc+3); |
| 445 | } |
| 446 | |
| 447 | close(fdesc) |
| 448 | int fdesc; |
| 449 | { |
| 450 | struct iob *file; |
| 451 | |
| 452 | fdesc -= 3; |
| 453 | if (fdesc < 0 || fdesc >= NFILES || ((file = &iob[fdesc])->i_flgs&F_ALLOC) == 0) |
| 454 | return(-1); |
| 455 | if ((file->i_flgs&F_FILE) == 0) |
| 456 | devclose(file); |
| 457 | file->i_flgs = 0; |
| 458 | return(0); |
| 459 | } |
| 460 | |
| 461 | exit() |
| 462 | { |
| 463 | _stop("Exit called"); |
| 464 | } |
| 465 | |
| 466 | _stop(s) |
| 467 | char *s; |
| 468 | { |
| 469 | int i; |
| 470 | |
| 471 | for (i = 0; i < NFILES; i++) |
| 472 | if (iob[i].i_flgs != 0) |
| 473 | close(i); |
| 474 | printf("%s\n", s); |
| 475 | _rtt(); |
| 476 | } |
| 477 | |
| 478 | trap(ps) |
| 479 | int ps; |
| 480 | { |
| 481 | printf("Trap %o\n", ps); |
| 482 | for (;;) |
| 483 | ; |
| 484 | } |