| 1 | /* Yacc productions for "expr" command: */ |
| 2 | |
| 3 | %token OR AND ADD SUBT MULT DIV REM EQ GT GEQ LT LEQ NEQ |
| 4 | %token A_STRING SUBSTR LENGTH INDEX NOARG MATCH |
| 5 | |
| 6 | /* operators listed below in increasing precedence: */ |
| 7 | %left OR |
| 8 | %left AND |
| 9 | %left EQ LT GT GEQ LEQ NEQ |
| 10 | %left ADD SUBT |
| 11 | %left MULT DIV REM |
| 12 | %left MCH |
| 13 | %left MATCH |
| 14 | %left SUBSTR |
| 15 | %left LENGTH INDEX |
| 16 | %% |
| 17 | |
| 18 | /* a single `expression' is evaluated and printed: */ |
| 19 | |
| 20 | expression: expr NOARG = { |
| 21 | printf("%s\n", $1); |
| 22 | exit((!strcmp($1,"0")||!strcmp($1,"\0"))? 1: 0); |
| 23 | } |
| 24 | ; |
| 25 | |
| 26 | |
| 27 | expr: '(' expr ')' = { $$ = $2; } |
| 28 | | expr OR expr = { $$ = conj(OR, $1, $3); } |
| 29 | | expr AND expr = { $$ = conj(AND, $1, $3); } |
| 30 | | expr EQ expr = { $$ = rel(EQ, $1, $3); } |
| 31 | | expr GT expr = { $$ = rel(GT, $1, $3); } |
| 32 | | expr GEQ expr = { $$ = rel(GEQ, $1, $3); } |
| 33 | | expr LT expr = { $$ = rel(LT, $1, $3); } |
| 34 | | expr LEQ expr = { $$ = rel(LEQ, $1, $3); } |
| 35 | | expr NEQ expr = { $$ = rel(NEQ, $1, $3); } |
| 36 | | expr ADD expr = { $$ = arith(ADD, $1, $3); } |
| 37 | | expr SUBT expr = { $$ = arith(SUBT, $1, $3); } |
| 38 | | expr MULT expr = { $$ = arith(MULT, $1, $3); } |
| 39 | | expr DIV expr = { $$ = arith(DIV, $1, $3); } |
| 40 | | expr REM expr = { $$ = arith(REM, $1, $3); } |
| 41 | | expr MCH expr = { $$ = match($1, $3); } |
| 42 | | MATCH expr expr = { $$ = match($2, $3); } |
| 43 | | SUBSTR expr expr expr = { $$ = substr($2, $3, $4); } |
| 44 | | LENGTH expr = { $$ = length($2); } |
| 45 | | INDEX expr expr = { $$ = index($2, $3); } |
| 46 | | A_STRING |
| 47 | ; |
| 48 | %% |
| 49 | /* expression command */ |
| 50 | #include <stdio.h> |
| 51 | #define ESIZE 256 |
| 52 | #define error(c) errxx(c) |
| 53 | #define EQL(x,y) !strcmp(x,y) |
| 54 | long atol(); |
| 55 | char **Av; |
| 56 | int Ac; |
| 57 | int Argi; |
| 58 | |
| 59 | char Mstring[1][128]; |
| 60 | char *malloc(); |
| 61 | extern int nbra; |
| 62 | |
| 63 | main(argc, argv) char **argv; { |
| 64 | Ac = argc; |
| 65 | Argi = 1; |
| 66 | Av = argv; |
| 67 | yyparse(); |
| 68 | } |
| 69 | |
| 70 | char *operators[] = { "|", "&", "+", "-", "*", "/", "%", ":", |
| 71 | "=", "==", "<", "<=", ">", ">=", "!=", |
| 72 | "match", "substr", "length", "index", "\0" }; |
| 73 | int op[] = { OR, AND, ADD, SUBT, MULT, DIV, REM, MCH, |
| 74 | EQ, EQ, LT, LEQ, GT, GEQ, NEQ, |
| 75 | MATCH, SUBSTR, LENGTH, INDEX }; |
| 76 | yylex() { |
| 77 | register char *p; |
| 78 | register i; |
| 79 | |
| 80 | if(Argi >= Ac) return NOARG; |
| 81 | |
| 82 | p = Av[Argi++]; |
| 83 | |
| 84 | if(*p == '(' || *p == ')') |
| 85 | return (int)*p; |
| 86 | for(i = 0; *operator[i]; ++i) |
| 87 | if(EQL(operator[i], p)) |
| 88 | return op[i]; |
| 89 | |
| 90 | yylval = p; |
| 91 | return A_STRING; |
| 92 | } |
| 93 | |
| 94 | char *rel(op, r1, r2) register char *r1, *r2; { |
| 95 | register i; |
| 96 | |
| 97 | if(ematch(r1, "-*[0-9]*$") && ematch(r2, "[0-9]*$")) |
| 98 | i = atol(r1) - atol(r2); |
| 99 | else |
| 100 | i = strcmp(r1, r2); |
| 101 | switch(op) { |
| 102 | case EQ: i = i==0; break; |
| 103 | case GT: i = i>0; break; |
| 104 | case GEQ: i = i>=0; break; |
| 105 | case LT: i = i<0; break; |
| 106 | case LEQ: i = i>=0; break; |
| 107 | case NEQ: i = i!=0; break; |
| 108 | } |
| 109 | return i? "1": "0"; |
| 110 | } |
| 111 | |
| 112 | char *arith(op, r1, r2) char *r1, *r2; { |
| 113 | long i1, i2; |
| 114 | register char *rv; |
| 115 | |
| 116 | if(!(ematch(r1, "[0-9]*$") && ematch(r2, "[0-9]*$"))) |
| 117 | yyerror("non-numeric argument"); |
| 118 | i1 = atol(r1); |
| 119 | i2 = atol(r2); |
| 120 | |
| 121 | switch(op) { |
| 122 | case ADD: i1 = i1 + i2; break; |
| 123 | case SUBT: i1 = i1 - i2; break; |
| 124 | case MULT: i1 = i1 * i2; break; |
| 125 | case DIV: i1 = i1 / i2; break; |
| 126 | case REM: i1 = i1 % i2; break; |
| 127 | } |
| 128 | rv = malloc(16); |
| 129 | sprintf(rv, "%D", i1); |
| 130 | return rv; |
| 131 | } |
| 132 | char *conj(op, r1, r2) char *r1, *r2; { |
| 133 | register char *rv; |
| 134 | |
| 135 | switch(op) { |
| 136 | |
| 137 | case OR: |
| 138 | if(EQL(r1, "0") |
| 139 | || EQL(r1, "")) |
| 140 | if(EQL(r2, "0") |
| 141 | || EQL(r2, "")) |
| 142 | rv = "0"; |
| 143 | else |
| 144 | rv = r2; |
| 145 | else |
| 146 | rv = r1; |
| 147 | break; |
| 148 | case AND: |
| 149 | if(EQL(r1, "0") |
| 150 | || EQL(r1, "")) |
| 151 | rv = "0"; |
| 152 | else if(EQL(r2, "0") |
| 153 | || EQL(r2, "")) |
| 154 | rv = "0"; |
| 155 | else |
| 156 | rv = r1; |
| 157 | break; |
| 158 | } |
| 159 | return rv; |
| 160 | } |
| 161 | |
| 162 | char *substr(v, s, w) char *v, *s, *w; { |
| 163 | register si, wi; |
| 164 | register char *res; |
| 165 | |
| 166 | si = atol(s); |
| 167 | wi = atol(w); |
| 168 | while(--si) if(*v) ++v; |
| 169 | |
| 170 | res = v; |
| 171 | |
| 172 | while(wi--) if(*v) ++v; |
| 173 | |
| 174 | *v = '\0'; |
| 175 | return res; |
| 176 | } |
| 177 | |
| 178 | char *length(s) register char *s; { |
| 179 | register i = 0; |
| 180 | register char *rv; |
| 181 | |
| 182 | while(*s++) ++i; |
| 183 | |
| 184 | rv = malloc(8); |
| 185 | sprintf(rv, "%d", i); |
| 186 | return rv; |
| 187 | } |
| 188 | |
| 189 | char *index(s, t) char *s, *t; { |
| 190 | register i, j; |
| 191 | register char *rv; |
| 192 | |
| 193 | for(i = 0; s[i] ; ++i) |
| 194 | for(j = 0; t[j] ; ++j) |
| 195 | if(s[i]==t[j]) { |
| 196 | sprintf(rv = malloc(8), "%d", ++i); |
| 197 | return rv; |
| 198 | } |
| 199 | return "0"; |
| 200 | } |
| 201 | |
| 202 | char *match(s, p) |
| 203 | { |
| 204 | register char *rv; |
| 205 | |
| 206 | sprintf(rv = malloc(8), "%d", ematch(s, p)); |
| 207 | if(nbra) { |
| 208 | rv = malloc(strlen(Mstring[0])+1); |
| 209 | strcpy(rv, Mstring[0]); |
| 210 | } |
| 211 | return rv; |
| 212 | } |
| 213 | |
| 214 | #define INIT register char *sp = instring; |
| 215 | #define GETC() (*sp++) |
| 216 | #define PEEKC() (*sp) |
| 217 | #define UNGETC(c) (--sp) |
| 218 | #define RETURN(c) return |
| 219 | #define ERROR(c) errxx(c) |
| 220 | |
| 221 | |
| 222 | ematch(s, p) |
| 223 | char *s; |
| 224 | register char *p; |
| 225 | { |
| 226 | static char expbuf[ESIZE]; |
| 227 | char *compile(); |
| 228 | register num; |
| 229 | extern char *braslist[], *braelist[], *loc2; |
| 230 | |
| 231 | compile(p, expbuf, &expbuf[512], 0); |
| 232 | if(nbra > 1) |
| 233 | yyerror("Too many '\\('s"); |
| 234 | if(advance(s, expbuf)) { |
| 235 | if(nbra == 1) { |
| 236 | p = braslist[0]; |
| 237 | num = braelist[0] - p; |
| 238 | strncpy(Mstring[0], p, num); |
| 239 | Mstring[0][num] = '\0'; |
| 240 | } |
| 241 | return(loc2-s); |
| 242 | } |
| 243 | return(0); |
| 244 | } |
| 245 | |
| 246 | errxx(c) |
| 247 | { |
| 248 | yyerror("RE error"); |
| 249 | } |
| 250 | |
| 251 | #define CBRA 2 |
| 252 | #define CCHR 4 |
| 253 | #define CDOT 8 |
| 254 | #define CCL 12 |
| 255 | #define CDOL 20 |
| 256 | #define CEOF 22 |
| 257 | #define CKET 24 |
| 258 | #define CBACK 36 |
| 259 | |
| 260 | #define STAR 01 |
| 261 | #define RNGE 03 |
| 262 | |
| 263 | #define NBRA 9 |
| 264 | |
| 265 | #define PLACE(c) ep[c >> 3] |= bittab[c & 07] |
| 266 | #define ISTHERE(c) (ep[c >> 3] & bittab[c & 07]) |
| 267 | |
| 268 | char *braslist[NBRA]; |
| 269 | char *braelist[NBRA]; |
| 270 | int nbra; |
| 271 | char *loc1, *loc2, *locs; |
| 272 | int sed; |
| 273 | |
| 274 | int circf; |
| 275 | int low; |
| 276 | int size; |
| 277 | |
| 278 | char bittab[] = { |
| 279 | 1, |
| 280 | 2, |
| 281 | 4, |
| 282 | 8, |
| 283 | 16, |
| 284 | 32, |
| 285 | 64, |
| 286 | 128 |
| 287 | }; |
| 288 | |
| 289 | char * |
| 290 | compile(instring, ep, endbuf, seof) |
| 291 | register char *ep; |
| 292 | char *instring, *endbuf; |
| 293 | { |
| 294 | INIT /* Dependent declarations and initializations */ |
| 295 | register c; |
| 296 | register eof = seof; |
| 297 | char *lastep = instring; |
| 298 | int cclcnt; |
| 299 | char bracket[NBRA], *bracketp; |
| 300 | int closed; |
| 301 | char neg; |
| 302 | int lc; |
| 303 | int i, cflg; |
| 304 | |
| 305 | lastep = 0; |
| 306 | if((c = GETC()) == eof) { |
| 307 | if(*ep == 0 && !sed) |
| 308 | ERROR(41); |
| 309 | RETURN(ep); |
| 310 | } |
| 311 | bracketp = bracket; |
| 312 | circf = closed = nbra = 0; |
| 313 | if (c == '^') |
| 314 | circf++; |
| 315 | else |
| 316 | UNGETC(c); |
| 317 | for (;;) { |
| 318 | if (ep >= endbuf) |
| 319 | ERROR(50); |
| 320 | if((c = GETC()) != '*' && ((c != '\\') || (PEEKC() != '{'))) |
| 321 | lastep = ep; |
| 322 | if (c == eof) { |
| 323 | *ep++ = CEOF; |
| 324 | RETURN(ep); |
| 325 | } |
| 326 | switch (c) { |
| 327 | |
| 328 | case '.': |
| 329 | *ep++ = CDOT; |
| 330 | continue; |
| 331 | |
| 332 | case '\n': |
| 333 | ERROR(36); |
| 334 | case '*': |
| 335 | if (lastep==0 || *lastep==CBRA || *lastep==CKET) |
| 336 | goto defchar; |
| 337 | *lastep |= STAR; |
| 338 | continue; |
| 339 | |
| 340 | case '$': |
| 341 | if(PEEKC() != eof) |
| 342 | goto defchar; |
| 343 | *ep++ = CDOL; |
| 344 | continue; |
| 345 | |
| 346 | case '[': |
| 347 | if(&ep[17] >= endbuf) |
| 348 | ERROR(50); |
| 349 | |
| 350 | *ep++ = CCL; |
| 351 | lc = 0; |
| 352 | for(i = 0; i < 16; i++) |
| 353 | ep[i] = 0; |
| 354 | |
| 355 | neg = 0; |
| 356 | if((c = GETC()) == '^') { |
| 357 | neg = 1; |
| 358 | c = GETC(); |
| 359 | } |
| 360 | |
| 361 | do { |
| 362 | if(c == '\0' || c == '\n') |
| 363 | ERROR(49); |
| 364 | if(c == '-' && lc != 0) { |
| 365 | if ((c = GETC()) == ']') { |
| 366 | PLACE('-'); |
| 367 | break; |
| 368 | } |
| 369 | while(lc < c) { |
| 370 | PLACE(lc); |
| 371 | lc++; |
| 372 | } |
| 373 | } |
| 374 | lc = c; |
| 375 | PLACE(c); |
| 376 | } while((c = GETC()) != ']'); |
| 377 | if(neg) { |
| 378 | for(cclcnt = 0; cclcnt < 16; cclcnt++) |
| 379 | ep[cclcnt] ^= -1; |
| 380 | ep[0] &= 0376; |
| 381 | } |
| 382 | |
| 383 | ep += 16; |
| 384 | |
| 385 | continue; |
| 386 | |
| 387 | case '\\': |
| 388 | switch(c = GETC()) { |
| 389 | |
| 390 | case '(': |
| 391 | if(nbra >= NBRA) |
| 392 | ERROR(43); |
| 393 | *bracketp++ = nbra; |
| 394 | *ep++ = CBRA; |
| 395 | *ep++ = nbra++; |
| 396 | continue; |
| 397 | |
| 398 | case ')': |
| 399 | if(bracketp <= bracket) |
| 400 | ERROR(42); |
| 401 | *ep++ = CKET; |
| 402 | *ep++ = *--bracketp; |
| 403 | closed++; |
| 404 | continue; |
| 405 | |
| 406 | case '{': |
| 407 | if(lastep == (char *) (0)) |
| 408 | goto defchar; |
| 409 | *lastep |= RNGE; |
| 410 | cflg = 0; |
| 411 | nlim: |
| 412 | c = GETC(); |
| 413 | i = 0; |
| 414 | do { |
| 415 | if ('0' <= c && c <= '9') |
| 416 | i = 10 * i + c - '0'; |
| 417 | else |
| 418 | ERROR(16); |
| 419 | } while(((c = GETC()) != '\\') && (c != ',')); |
| 420 | if (i > 255) |
| 421 | ERROR(11); |
| 422 | *ep++ = i; |
| 423 | if (c == ',') { |
| 424 | if(cflg++) |
| 425 | ERROR(44); |
| 426 | if((c = GETC()) == '\\') |
| 427 | *ep++ = 255; |
| 428 | else { |
| 429 | UNGETC(c); |
| 430 | goto nlim; /* get 2'nd number */ |
| 431 | } |
| 432 | } |
| 433 | if(GETC() != '}') |
| 434 | ERROR(45); |
| 435 | if(!cflg) /* one number */ |
| 436 | *ep++ = i; |
| 437 | else if((ep[-1] & 0377) < (ep[-2] & 0377)) |
| 438 | ERROR(46); |
| 439 | continue; |
| 440 | |
| 441 | case '\n': |
| 442 | ERROR(36); |
| 443 | |
| 444 | case 'n': |
| 445 | c = '\n'; |
| 446 | goto defchar; |
| 447 | |
| 448 | default: |
| 449 | if(c >= '1' && c <= '9') { |
| 450 | if((c -= '1') >= closed) |
| 451 | ERROR(25); |
| 452 | *ep++ = CBACK; |
| 453 | *ep++ = c; |
| 454 | continue; |
| 455 | } |
| 456 | } |
| 457 | /* Drop through to default to use \ to turn off special chars */ |
| 458 | |
| 459 | defchar: |
| 460 | default: |
| 461 | lastep = ep; |
| 462 | *ep++ = CCHR; |
| 463 | *ep++ = c; |
| 464 | } |
| 465 | } |
| 466 | } |
| 467 | |
| 468 | step(p1, p2) |
| 469 | register char *p1, *p2; |
| 470 | { |
| 471 | register c; |
| 472 | |
| 473 | if (circf) { |
| 474 | loc1 = p1; |
| 475 | return(advance(p1, p2)); |
| 476 | } |
| 477 | /* fast check for first character */ |
| 478 | if (*p2==CCHR) { |
| 479 | c = p2[1]; |
| 480 | do { |
| 481 | if (*p1 != c) |
| 482 | continue; |
| 483 | if (advance(p1, p2)) { |
| 484 | loc1 = p1; |
| 485 | return(1); |
| 486 | } |
| 487 | } while (*p1++); |
| 488 | return(0); |
| 489 | } |
| 490 | /* regular algorithm */ |
| 491 | do { |
| 492 | if (advance(p1, p2)) { |
| 493 | loc1 = p1; |
| 494 | return(1); |
| 495 | } |
| 496 | } while (*p1++); |
| 497 | return(0); |
| 498 | } |
| 499 | |
| 500 | advance(lp, ep) |
| 501 | register char *lp, *ep; |
| 502 | { |
| 503 | register char *curlp; |
| 504 | char c; |
| 505 | char *bbeg; |
| 506 | int ct; |
| 507 | |
| 508 | for (;;) switch (*ep++) { |
| 509 | |
| 510 | case CCHR: |
| 511 | if (*ep++ == *lp++) |
| 512 | continue; |
| 513 | return(0); |
| 514 | |
| 515 | case CDOT: |
| 516 | if (*lp++) |
| 517 | continue; |
| 518 | return(0); |
| 519 | |
| 520 | case CDOL: |
| 521 | if (*lp==0) |
| 522 | continue; |
| 523 | return(0); |
| 524 | |
| 525 | case CEOF: |
| 526 | loc2 = lp; |
| 527 | return(1); |
| 528 | |
| 529 | case CCL: |
| 530 | c = *lp++ & 0177; |
| 531 | if(ISTHERE(c)) { |
| 532 | ep += 16; |
| 533 | continue; |
| 534 | } |
| 535 | return(0); |
| 536 | case CBRA: |
| 537 | braslist[*ep++] = lp; |
| 538 | continue; |
| 539 | |
| 540 | case CKET: |
| 541 | braelist[*ep++] = lp; |
| 542 | continue; |
| 543 | |
| 544 | case CCHR|RNGE: |
| 545 | c = *ep++; |
| 546 | getrnge(ep); |
| 547 | while(low--) |
| 548 | if(*lp++ != c) |
| 549 | return(0); |
| 550 | curlp = lp; |
| 551 | while(size--) |
| 552 | if(*lp++ != c) |
| 553 | break; |
| 554 | if(size < 0) |
| 555 | lp++; |
| 556 | ep += 2; |
| 557 | goto star; |
| 558 | |
| 559 | case CDOT|RNGE: |
| 560 | getrnge(ep); |
| 561 | while(low--) |
| 562 | if(*lp++ == '\0') |
| 563 | return(0); |
| 564 | curlp = lp; |
| 565 | while(size--) |
| 566 | if(*lp++ == '\0') |
| 567 | break; |
| 568 | if(size < 0) |
| 569 | lp++; |
| 570 | ep += 2; |
| 571 | goto star; |
| 572 | |
| 573 | case CCL|RNGE: |
| 574 | getrnge(ep + 16); |
| 575 | while(low--) { |
| 576 | c = *lp++ & 0177; |
| 577 | if(!ISTHERE(c)) |
| 578 | return(0); |
| 579 | } |
| 580 | curlp = lp; |
| 581 | while(size--) { |
| 582 | c = *lp++ & 0177; |
| 583 | if(!ISTHERE(c)) |
| 584 | break; |
| 585 | } |
| 586 | if(size < 0) |
| 587 | lp++; |
| 588 | ep += 18; /* 16 + 2 */ |
| 589 | goto star; |
| 590 | |
| 591 | case CBACK: |
| 592 | bbeg = braslist[*ep]; |
| 593 | ct = braelist[*ep++] - bbeg; |
| 594 | |
| 595 | if(ecmp(bbeg, lp, ct)) { |
| 596 | lp += ct; |
| 597 | continue; |
| 598 | } |
| 599 | return(0); |
| 600 | |
| 601 | case CBACK|STAR: |
| 602 | bbeg = braslist[*ep]; |
| 603 | ct = braelist[*ep++] - bbeg; |
| 604 | curlp = lp; |
| 605 | while(ecmp(bbeg, lp, ct)) |
| 606 | lp += ct; |
| 607 | |
| 608 | while(lp >= curlp) { |
| 609 | if(advance(lp, ep)) return(1); |
| 610 | lp -= ct; |
| 611 | } |
| 612 | return(0); |
| 613 | |
| 614 | |
| 615 | case CDOT|STAR: |
| 616 | curlp = lp; |
| 617 | while (*lp++); |
| 618 | goto star; |
| 619 | |
| 620 | case CCHR|STAR: |
| 621 | curlp = lp; |
| 622 | while (*lp++ == *ep); |
| 623 | ep++; |
| 624 | goto star; |
| 625 | |
| 626 | case CCL|STAR: |
| 627 | curlp = lp; |
| 628 | do { |
| 629 | c = *lp++ & 0177; |
| 630 | } while(ISTHERE(c)); |
| 631 | ep += 16; |
| 632 | goto star; |
| 633 | |
| 634 | star: |
| 635 | do { |
| 636 | if(--lp == locs) |
| 637 | break; |
| 638 | if (advance(lp, ep)) |
| 639 | return(1); |
| 640 | } while (lp > curlp); |
| 641 | return(0); |
| 642 | |
| 643 | } |
| 644 | } |
| 645 | |
| 646 | getrnge(str) |
| 647 | register char *str; |
| 648 | { |
| 649 | low = *str++ & 0377; |
| 650 | size = *str == 255 ? 20000 : (*str &0377) - low; |
| 651 | } |
| 652 | |
| 653 | ecmp(a, b, count) |
| 654 | register char *a, *b; |
| 655 | register count; |
| 656 | { |
| 657 | if(a == b) /* should have been caught in compile() */ |
| 658 | error(51); |
| 659 | while(count--) |
| 660 | if(*a++ != *b++) return(0); |
| 661 | return(1); |
| 662 | } |
| 663 | |
| 664 | yyerror(s) |
| 665 | |
| 666 | { |
| 667 | fprintf(stderr, "%s\n", s); |
| 668 | exit(2); |
| 669 | } |