| 1 | /* |
| 2 | * grep -- print lines matching (or not matching) a pattern |
| 3 | * |
| 4 | * status returns: |
| 5 | * 0 - ok, and some matches |
| 6 | * 1 - ok, but no matches |
| 7 | * 2 - some error |
| 8 | */ |
| 9 | |
| 10 | #include <stdio.h> |
| 11 | #include <ctype.h> |
| 12 | #include <sys/param.h> |
| 13 | |
| 14 | #define CBRA 1 |
| 15 | #define CCHR 2 |
| 16 | #define CDOT 4 |
| 17 | #define CCL 6 |
| 18 | #define NCCL 8 |
| 19 | #define CDOL 10 |
| 20 | #define CEOF 11 |
| 21 | #define CKET 12 |
| 22 | #define CBACK 18 |
| 23 | |
| 24 | #define STAR 01 |
| 25 | |
| 26 | #define LBSIZE 512 |
| 27 | #define ESIZE 256 |
| 28 | #define NBRA 9 |
| 29 | |
| 30 | char expbuf[ESIZE]; |
| 31 | long lnum; |
| 32 | char linebuf[LBSIZE+1]; |
| 33 | char ybuf[ESIZE]; |
| 34 | int bflag; |
| 35 | int lflag; |
| 36 | int nflag; |
| 37 | int cflag; |
| 38 | int vflag; |
| 39 | int nfile; |
| 40 | int hflag = 1; |
| 41 | int sflag; |
| 42 | int yflag; |
| 43 | int circf; |
| 44 | long tln; |
| 45 | int nsucc; |
| 46 | char *braslist[NBRA]; |
| 47 | char *braelist[NBRA]; |
| 48 | char bittab[] = { |
| 49 | 1, |
| 50 | 2, |
| 51 | 4, |
| 52 | 8, |
| 53 | 16, |
| 54 | 32, |
| 55 | 64, |
| 56 | 128 |
| 57 | }; |
| 58 | |
| 59 | main(argc, argv) |
| 60 | char **argv; |
| 61 | { |
| 62 | while (--argc > 0 && (++argv)[0][0]=='-') |
| 63 | switch (argv[0][1]) { |
| 64 | |
| 65 | case 'y': |
| 66 | yflag++; |
| 67 | continue; |
| 68 | |
| 69 | case 'h': |
| 70 | hflag = 0; |
| 71 | continue; |
| 72 | |
| 73 | case 's': |
| 74 | sflag++; |
| 75 | continue; |
| 76 | |
| 77 | case 'v': |
| 78 | vflag++; |
| 79 | continue; |
| 80 | |
| 81 | case 'b': |
| 82 | bflag++; |
| 83 | continue; |
| 84 | |
| 85 | case 'l': |
| 86 | lflag++; |
| 87 | continue; |
| 88 | |
| 89 | case 'c': |
| 90 | cflag++; |
| 91 | continue; |
| 92 | |
| 93 | case 'n': |
| 94 | nflag++; |
| 95 | continue; |
| 96 | |
| 97 | case 'e': |
| 98 | --argc; |
| 99 | ++argv; |
| 100 | goto out; |
| 101 | |
| 102 | default: |
| 103 | errexit("grep: unknown flag\n", (char *)NULL); |
| 104 | continue; |
| 105 | } |
| 106 | out: |
| 107 | if (argc<=0) |
| 108 | exit(2); |
| 109 | if (yflag) { |
| 110 | register char *p, *s; |
| 111 | for (s = ybuf, p = *argv; *p; ) { |
| 112 | if (*p == '\\') { |
| 113 | *s++ = *p++; |
| 114 | if (*p) |
| 115 | *s++ = *p++; |
| 116 | } else if (*p == '[') { |
| 117 | while (*p != '\0' && *p != ']') |
| 118 | *s++ = *p++; |
| 119 | } else if (islower(*p)) { |
| 120 | *s++ = '['; |
| 121 | *s++ = toupper(*p); |
| 122 | *s++ = *p++; |
| 123 | *s++ = ']'; |
| 124 | } else |
| 125 | *s++ = *p++; |
| 126 | if (s >= ybuf+ESIZE-5) |
| 127 | errexit("grep: argument too long\n", (char *)NULL); |
| 128 | } |
| 129 | *s = '\0'; |
| 130 | *argv = ybuf; |
| 131 | } |
| 132 | compile(*argv); |
| 133 | nfile = --argc; |
| 134 | if (argc<=0) { |
| 135 | if (lflag) |
| 136 | exit(1); |
| 137 | execute((char *)NULL); |
| 138 | } else while (--argc >= 0) { |
| 139 | argv++; |
| 140 | execute(*argv); |
| 141 | } |
| 142 | exit(nsucc == 0); |
| 143 | } |
| 144 | |
| 145 | compile(astr) |
| 146 | char *astr; |
| 147 | { |
| 148 | register c; |
| 149 | register char *ep, *sp; |
| 150 | char *cstart; |
| 151 | char *lastep; |
| 152 | int cclcnt; |
| 153 | char bracket[NBRA], *bracketp; |
| 154 | int closed; |
| 155 | char numbra; |
| 156 | char neg; |
| 157 | |
| 158 | ep = expbuf; |
| 159 | sp = astr; |
| 160 | lastep = 0; |
| 161 | bracketp = bracket; |
| 162 | closed = numbra = 0; |
| 163 | if (*sp == '^') { |
| 164 | circf++; |
| 165 | sp++; |
| 166 | } |
| 167 | for (;;) { |
| 168 | if (ep >= &expbuf[ESIZE]) |
| 169 | goto cerror; |
| 170 | if ((c = *sp++) != '*') |
| 171 | lastep = ep; |
| 172 | switch (c) { |
| 173 | |
| 174 | case '\0': |
| 175 | *ep++ = CEOF; |
| 176 | return; |
| 177 | |
| 178 | case '.': |
| 179 | *ep++ = CDOT; |
| 180 | continue; |
| 181 | |
| 182 | case '*': |
| 183 | if (lastep==0 || *lastep==CBRA || *lastep==CKET) |
| 184 | goto defchar; |
| 185 | *lastep |= STAR; |
| 186 | continue; |
| 187 | |
| 188 | case '$': |
| 189 | if (*sp != '\0') |
| 190 | goto defchar; |
| 191 | *ep++ = CDOL; |
| 192 | continue; |
| 193 | |
| 194 | case '[': |
| 195 | if(&ep[17] >= &expbuf[ESIZE]) |
| 196 | goto cerror; |
| 197 | *ep++ = CCL; |
| 198 | neg = 0; |
| 199 | if((c = *sp++) == '^') { |
| 200 | neg = 1; |
| 201 | c = *sp++; |
| 202 | } |
| 203 | cstart = sp; |
| 204 | do { |
| 205 | if (c=='\0') |
| 206 | goto cerror; |
| 207 | if (c=='-' && sp>cstart && *sp!=']') { |
| 208 | for (c = sp[-2]; c<*sp; c++) |
| 209 | ep[c>>3] |= bittab[c&07]; |
| 210 | sp++; |
| 211 | } |
| 212 | ep[c>>3] |= bittab[c&07]; |
| 213 | } while((c = *sp++) != ']'); |
| 214 | if(neg) { |
| 215 | for(cclcnt = 0; cclcnt < 16; cclcnt++) |
| 216 | ep[cclcnt] ^= -1; |
| 217 | ep[0] &= 0376; |
| 218 | } |
| 219 | |
| 220 | ep += 16; |
| 221 | |
| 222 | continue; |
| 223 | |
| 224 | case '\\': |
| 225 | if((c = *sp++) == '(') { |
| 226 | if(numbra >= NBRA) { |
| 227 | goto cerror; |
| 228 | } |
| 229 | *bracketp++ = numbra; |
| 230 | *ep++ = CBRA; |
| 231 | *ep++ = numbra++; |
| 232 | continue; |
| 233 | } |
| 234 | if(c == ')') { |
| 235 | if(bracketp <= bracket) { |
| 236 | goto cerror; |
| 237 | } |
| 238 | *ep++ = CKET; |
| 239 | *ep++ = *--bracketp; |
| 240 | closed++; |
| 241 | continue; |
| 242 | } |
| 243 | |
| 244 | if(c >= '1' && c <= '9') { |
| 245 | if((c -= '1') >= closed) |
| 246 | goto cerror; |
| 247 | *ep++ = CBACK; |
| 248 | *ep++ = c; |
| 249 | continue; |
| 250 | } |
| 251 | |
| 252 | defchar: |
| 253 | default: |
| 254 | *ep++ = CCHR; |
| 255 | *ep++ = c; |
| 256 | } |
| 257 | } |
| 258 | cerror: |
| 259 | errexit("grep: RE error\n", (char *)NULL); |
| 260 | } |
| 261 | |
| 262 | execute(file) |
| 263 | char *file; |
| 264 | { |
| 265 | register char *p1, *p2; |
| 266 | register c; |
| 267 | |
| 268 | if (file) { |
| 269 | if (freopen(file, "r", stdin) == NULL) |
| 270 | errexit("grep: can't open %s\n", file); |
| 271 | } |
| 272 | lnum = 0; |
| 273 | tln = 0; |
| 274 | for (;;) { |
| 275 | lnum++; |
| 276 | p1 = linebuf; |
| 277 | while ((c = getchar()) != '\n') { |
| 278 | if (c == EOF) { |
| 279 | if (cflag) { |
| 280 | if (nfile>1) |
| 281 | printf("%s:", file); |
| 282 | printf("%D\n", tln); |
| 283 | } |
| 284 | return; |
| 285 | } |
| 286 | *p1++ = c; |
| 287 | if (p1 >= &linebuf[LBSIZE-1]) |
| 288 | break; |
| 289 | } |
| 290 | *p1++ = '\0'; |
| 291 | p1 = linebuf; |
| 292 | p2 = expbuf; |
| 293 | if (circf) { |
| 294 | if (advance(p1, p2)) |
| 295 | goto found; |
| 296 | goto nfound; |
| 297 | } |
| 298 | /* fast check for first character */ |
| 299 | if (*p2==CCHR) { |
| 300 | c = p2[1]; |
| 301 | do { |
| 302 | if (*p1!=c) |
| 303 | continue; |
| 304 | if (advance(p1, p2)) |
| 305 | goto found; |
| 306 | } while (*p1++); |
| 307 | goto nfound; |
| 308 | } |
| 309 | /* regular algorithm */ |
| 310 | do { |
| 311 | if (advance(p1, p2)) |
| 312 | goto found; |
| 313 | } while (*p1++); |
| 314 | nfound: |
| 315 | if (vflag) |
| 316 | succeed(file); |
| 317 | continue; |
| 318 | found: |
| 319 | if (vflag==0) |
| 320 | succeed(file); |
| 321 | } |
| 322 | } |
| 323 | |
| 324 | advance(lp, ep) |
| 325 | register char *lp, *ep; |
| 326 | { |
| 327 | register char *curlp; |
| 328 | char c; |
| 329 | char *bbeg; |
| 330 | int ct; |
| 331 | |
| 332 | for (;;) switch (*ep++) { |
| 333 | |
| 334 | case CCHR: |
| 335 | if (*ep++ == *lp++) |
| 336 | continue; |
| 337 | return(0); |
| 338 | |
| 339 | case CDOT: |
| 340 | if (*lp++) |
| 341 | continue; |
| 342 | return(0); |
| 343 | |
| 344 | case CDOL: |
| 345 | if (*lp==0) |
| 346 | continue; |
| 347 | return(0); |
| 348 | |
| 349 | case CEOF: |
| 350 | return(1); |
| 351 | |
| 352 | case CCL: |
| 353 | c = *lp++ & 0177; |
| 354 | if(ep[c>>3] & bittab[c & 07]) { |
| 355 | ep += 16; |
| 356 | continue; |
| 357 | } |
| 358 | return(0); |
| 359 | case CBRA: |
| 360 | braslist[*ep++] = lp; |
| 361 | continue; |
| 362 | |
| 363 | case CKET: |
| 364 | braelist[*ep++] = lp; |
| 365 | continue; |
| 366 | |
| 367 | case CBACK: |
| 368 | bbeg = braslist[*ep]; |
| 369 | if (braelist[*ep]==0) |
| 370 | return(0); |
| 371 | ct = braelist[*ep++] - bbeg; |
| 372 | if(ecmp(bbeg, lp, ct)) { |
| 373 | lp += ct; |
| 374 | continue; |
| 375 | } |
| 376 | return(0); |
| 377 | |
| 378 | case CBACK|STAR: |
| 379 | bbeg = braslist[*ep]; |
| 380 | if (braelist[*ep]==0) |
| 381 | return(0); |
| 382 | ct = braelist[*ep++] - bbeg; |
| 383 | curlp = lp; |
| 384 | while(ecmp(bbeg, lp, ct)) |
| 385 | lp += ct; |
| 386 | while(lp >= curlp) { |
| 387 | if(advance(lp, ep)) return(1); |
| 388 | lp -= ct; |
| 389 | } |
| 390 | return(0); |
| 391 | |
| 392 | |
| 393 | case CDOT|STAR: |
| 394 | curlp = lp; |
| 395 | while (*lp++); |
| 396 | goto star; |
| 397 | |
| 398 | case CCHR|STAR: |
| 399 | curlp = lp; |
| 400 | while (*lp++ == *ep); |
| 401 | ep++; |
| 402 | goto star; |
| 403 | |
| 404 | case CCL|STAR: |
| 405 | curlp = lp; |
| 406 | do { |
| 407 | c = *lp++ & 0177; |
| 408 | } while(ep[c>>3] & bittab[c & 07]); |
| 409 | ep += 16; |
| 410 | goto star; |
| 411 | |
| 412 | star: |
| 413 | if(--lp == curlp) { |
| 414 | continue; |
| 415 | } |
| 416 | |
| 417 | if(*ep == CCHR) { |
| 418 | c = ep[1]; |
| 419 | do { |
| 420 | if(*lp != c) |
| 421 | continue; |
| 422 | if(advance(lp, ep)) |
| 423 | return(1); |
| 424 | } while(lp-- > curlp); |
| 425 | return(0); |
| 426 | } |
| 427 | |
| 428 | do { |
| 429 | if (advance(lp, ep)) |
| 430 | return(1); |
| 431 | } while (lp-- > curlp); |
| 432 | return(0); |
| 433 | |
| 434 | default: |
| 435 | errexit("grep RE botch\n", (char *)NULL); |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | succeed(f) |
| 440 | char *f; |
| 441 | { |
| 442 | long ftell(); |
| 443 | nsucc = 1; |
| 444 | if (sflag) |
| 445 | return; |
| 446 | if (cflag) { |
| 447 | tln++; |
| 448 | return; |
| 449 | } |
| 450 | if (lflag) { |
| 451 | printf("%s\n", f); |
| 452 | fseek(stdin, 0l, 2); |
| 453 | return; |
| 454 | } |
| 455 | if (nfile > 1 && hflag) |
| 456 | printf("%s:", f); |
| 457 | if (bflag) |
| 458 | printf("%ld:", (ftell(stdin)-1)/BSIZE); |
| 459 | if (nflag) |
| 460 | printf("%ld:", lnum); |
| 461 | printf("%s\n", linebuf); |
| 462 | } |
| 463 | |
| 464 | ecmp(a, b, count) |
| 465 | char *a, *b; |
| 466 | { |
| 467 | register cc = count; |
| 468 | while(cc--) |
| 469 | if(*a++ != *b++) return(0); |
| 470 | return(1); |
| 471 | } |
| 472 | |
| 473 | errexit(s, f) |
| 474 | char *s, *f; |
| 475 | { |
| 476 | fprintf(stderr, s, f); |
| 477 | exit(2); |
| 478 | } |