1 /*- 2 * Copyright (c) 1992 Diomidis Spinellis. 3 * Copyright (c) 1992 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * Diomidis Spinellis of Imperial College, University of London. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the University of 20 * California, Berkeley and its contributors. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 */ 37 38 #ifndef lint 39 static char sccsid[] = "@(#)compile.c 5.6 (Berkeley) 11/2/92"; 40 #endif /* not lint */ 41 42 #include <sys/types.h> 43 #include <sys/stat.h> 44 45 #include <ctype.h> 46 #include <errno.h> 47 #include <fcntl.h> 48 #include <limits.h> 49 #include <regex.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 54 #include "defs.h" 55 #include "extern.h" 56 57 static char *compile_addr __P((char *, struct s_addr *)); 58 static char *compile_delimited __P((char *, char *)); 59 static char *compile_flags __P((char *, struct s_subst *)); 60 static char *compile_re __P((char *, regex_t **)); 61 static char *compile_subst __P((char *, struct s_subst *)); 62 static char *compile_text __P((void)); 63 static char *compile_tr __P((char *, char **)); 64 static struct s_command 65 **compile_stream __P((char *, struct s_command **, char *)); 66 static char *duptoeol __P((char *)); 67 static struct s_command 68 *findlabel __P((struct s_command *, struct s_command *)); 69 static void fixuplabel __P((struct s_command *, struct s_command *, 70 struct s_command *)); 71 72 /* 73 * Command specification. This is used to drive the command parser. 74 */ 75 struct s_format { 76 char code; /* Command code */ 77 int naddr; /* Number of address args */ 78 enum e_args args; /* Argument type */ 79 }; 80 81 static struct s_format cmd_fmts[] = { 82 {'{', 2, GROUP}, 83 {'a', 1, TEXT}, 84 {'b', 2, BRANCH}, 85 {'c', 2, TEXT}, 86 {'d', 2, EMPTY}, 87 {'D', 2, EMPTY}, 88 {'g', 2, EMPTY}, 89 {'G', 2, EMPTY}, 90 {'h', 2, EMPTY}, 91 {'H', 2, EMPTY}, 92 {'i', 1, TEXT}, 93 {'l', 2, EMPTY}, 94 {'n', 2, EMPTY}, 95 {'N', 2, EMPTY}, 96 {'p', 2, EMPTY}, 97 {'P', 2, EMPTY}, 98 {'q', 1, EMPTY}, 99 {'r', 1, RFILE}, 100 {'s', 2, SUBST}, 101 {'t', 2, BRANCH}, 102 {'w', 2, WFILE}, 103 {'x', 2, EMPTY}, 104 {'y', 2, TR}, 105 {'!', 2, NONSEL}, 106 {':', 0, LABEL}, 107 {'#', 0, COMMENT}, 108 {'=', 1, EMPTY}, 109 {'\0', 0, COMMENT}, 110 }; 111 112 /* The compiled program. */ 113 struct s_command *prog; 114 115 /* 116 * Compile the program into prog. 117 * Initialise appends. 118 */ 119 void 120 compile() 121 { 122 *compile_stream(NULL, &prog, NULL) = NULL; 123 fixuplabel(prog, prog, NULL); 124 appends = xmalloc(sizeof(struct s_appends) * appendnum); 125 match = xmalloc((maxnsub + 1) * sizeof(regmatch_t)); 126 } 127 128 #define EATSPACE() do { \ 129 if (p) \ 130 while (*p && isascii(*p) && isspace(*p)) \ 131 p++; \ 132 } while (0) 133 134 static struct s_command ** 135 compile_stream(terminator, link, p) 136 char *terminator; 137 struct s_command **link; 138 register char *p; 139 { 140 static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */ 141 struct s_command *cmd, *cmd2; 142 struct s_format *fp; 143 int naddr; /* Number of addresses */ 144 145 if (p != NULL) 146 goto semicolon; 147 for (;;) { 148 if ((p = cu_fgets(lbuf, sizeof(lbuf))) == NULL) { 149 if (terminator != NULL) 150 err(COMPILE, "unexpected EOF (pending }'s)"); 151 return (link); 152 } 153 154 semicolon: EATSPACE(); 155 if (p && (*p == '#' || *p == '\0')) 156 continue; 157 if (*p == '}') { 158 if (terminator == NULL) 159 err(COMPILE, "unexpected }"); 160 return (link); 161 } 162 *link = cmd = xmalloc(sizeof(struct s_command)); 163 link = &cmd->next; 164 cmd->nonsel = cmd->inrange = 0; 165 /* First parse the addresses */ 166 naddr = 0; 167 cmd->a1 = cmd->a2 = NULL; 168 169 /* Valid characters to start an address */ 170 #define addrchar(c) (strchr("0123456789/\\$", (c))) 171 if (addrchar(*p)) { 172 naddr++; 173 cmd->a1 = xmalloc(sizeof(struct s_addr)); 174 p = compile_addr(p, cmd->a1); 175 EATSPACE(); /* EXTENSION */ 176 if (*p == ',') { 177 naddr++; 178 p++; 179 EATSPACE(); /* EXTENSION */ 180 cmd->a2 = xmalloc(sizeof(struct s_addr)); 181 p = compile_addr(p, cmd->a2); 182 } 183 } 184 185 nonsel: /* Now parse the command */ 186 EATSPACE(); 187 if (!*p) 188 err(COMPILE, "command expected"); 189 cmd->code = *p; 190 for (fp = cmd_fmts; fp->code; fp++) 191 if (fp->code == *p) 192 break; 193 if (!fp->code) 194 err(COMPILE, "invalid command code %c", *p); 195 if (naddr > fp->naddr) 196 err(COMPILE, 197 "command %c expects up to %d address(es), found %d", *p, fp->naddr, naddr); 198 switch (fp->args) { 199 case NONSEL: /* ! */ 200 cmd->nonsel = ! cmd->nonsel; 201 p++; 202 goto nonsel; 203 case GROUP: /* { */ 204 p++; 205 EATSPACE(); 206 if (!*p) 207 p = NULL; 208 cmd2 = xmalloc(sizeof(struct s_command)); 209 cmd2->code = '}'; 210 *compile_stream("}", &cmd->u.c, p) = cmd2; 211 cmd->next = cmd2; 212 link = &cmd2->next; 213 break; 214 case EMPTY: /* d D g G h H l n N p P q x = \0 */ 215 p++; 216 EATSPACE(); 217 if (*p == ';') { 218 p++; 219 link = &cmd->next; 220 goto semicolon; 221 } 222 if (*p) 223 err(COMPILE, 224 "extra characters at the end of %c command", cmd->code); 225 break; 226 case TEXT: /* a c i */ 227 p++; 228 EATSPACE(); 229 if (*p != '\\') 230 err(COMPILE, 231 "command %c expects \\ followed by text", cmd->code); 232 p++; 233 EATSPACE(); 234 if (*p) 235 err(COMPILE, 236 "extra characters after \\ at the end of %c command", cmd->code); 237 cmd->t = compile_text(); 238 break; 239 case COMMENT: /* \0 # */ 240 break; 241 case WFILE: /* w */ 242 p++; 243 EATSPACE(); 244 if (*p == '\0') 245 err(COMPILE, "filename expected"); 246 cmd->t = duptoeol(p); 247 if (aflag) 248 cmd->u.fd = -1; 249 else if ((cmd->u.fd = open(p, 250 O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, 251 DEFFILEMODE)) == -1) 252 err(FATAL, "%s: %s\n", p, strerror(errno)); 253 break; 254 case RFILE: /* r */ 255 p++; 256 EATSPACE(); 257 if (*p == '\0') 258 err(COMPILE, "filename expected"); 259 else 260 cmd->t = duptoeol(p); 261 break; 262 case BRANCH: /* b t */ 263 p++; 264 EATSPACE(); 265 if (*p == '\0') 266 cmd->t = NULL; 267 else 268 cmd->t = duptoeol(p); 269 break; 270 case LABEL: /* : */ 271 p++; 272 EATSPACE(); 273 cmd->t = duptoeol(p); 274 if (strlen(p) == 0) 275 err(COMPILE, "empty label"); 276 break; 277 case SUBST: /* s */ 278 p++; 279 if (*p == '\0' || *p == '\\') 280 err(COMPILE, 281 "substitute pattern can not be delimited by newline or backslash"); 282 cmd->u.s = xmalloc(sizeof(struct s_subst)); 283 p = compile_re(p, &cmd->u.s->re); 284 if (p == NULL) 285 err(COMPILE, "unterminated substitute pattern"); 286 --p; 287 p = compile_subst(p, cmd->u.s); 288 p = compile_flags(p, cmd->u.s); 289 EATSPACE(); 290 if (*p == ';') { 291 p++; 292 link = &cmd->next; 293 goto semicolon; 294 } 295 break; 296 case TR: /* y */ 297 p++; 298 p = compile_tr(p, (char **)&cmd->u.y); 299 EATSPACE(); 300 if (*p == ';') { 301 p++; 302 link = &cmd->next; 303 goto semicolon; 304 } 305 if (*p) 306 err(COMPILE, 307 "extra text at the end of a transform command"); 308 break; 309 } 310 } 311 } 312 313 /* 314 * Get a delimited string. P points to the delimeter of the string; d points 315 * to a buffer area. Newline and delimiter escapes are processed; other 316 * escapes are ignored. 317 * 318 * Returns a pointer to the first character after the final delimiter or NULL 319 * in the case of a non-terminated string. The character array d is filled 320 * with the processed string. 321 */ 322 static char * 323 compile_delimited(p, d) 324 char *p, *d; 325 { 326 char c; 327 328 c = *p++; 329 if (c == '\0') 330 return (NULL); 331 else if (c == '\\') 332 err(COMPILE, "\\ can not be used as a string delimiter"); 333 else if (c == '\n') 334 err(COMPILE, "newline can not be used as a string delimiter"); 335 while (*p) { 336 if (*p == '\\' && p[1] == c) 337 p++; 338 else if (*p == '\\' && p[1] == 'n') { 339 *d++ = '\n'; 340 p += 2; 341 continue; 342 } else if (*p == '\\' && p[1] == '\\') 343 *d++ = *p++; 344 else if (*p == c) { 345 *d = '\0'; 346 return (p + 1); 347 } 348 *d++ = *p++; 349 } 350 return (NULL); 351 } 352 353 /* 354 * Get a regular expression. P points to the delimiter of the regular 355 * expression; repp points to the address of a regexp pointer. Newline 356 * and delimiter escapes are processed; other escapes are ignored. 357 * Returns a pointer to the first character after the final delimiter 358 * or NULL in the case of a non terminated regular expression. The regexp 359 * pointer is set to the compiled regular expression. 360 * Cflags are passed to regcomp. 361 */ 362 static char * 363 compile_re(p, repp) 364 char *p; 365 regex_t **repp; 366 { 367 int eval; 368 char re[_POSIX2_LINE_MAX + 1]; 369 370 p = compile_delimited(p, re); 371 if (p && strlen(re) == 0) { 372 *repp = NULL; 373 return (p); 374 } 375 *repp = xmalloc(sizeof(regex_t)); 376 #ifdef GNU_REGEX 377 /* initialize pattern buffer */ 378 (*repp)->buffer = NULL; 379 (*repp)->allocated = 0L; 380 (*repp)->fastmap = (char *) malloc(FASTMAP_SIZE); 381 (*repp)->translate = 0; 382 #endif 383 if (p && (eval = regcomp(*repp, re, 0)) != 0) 384 err(COMPILE, "RE error: %s", strregerror(eval, *repp)); 385 if (maxnsub < (*repp)->re_nsub) 386 maxnsub = (*repp)->re_nsub; 387 return (p); 388 } 389 390 /* 391 * Compile the substitution string of a regular expression and set res to 392 * point to a saved copy of it. Nsub is the number of parenthesized regular 393 * expressions. 394 */ 395 static char * 396 compile_subst(p, s) 397 char *p; 398 struct s_subst *s; 399 { 400 static char lbuf[_POSIX2_LINE_MAX + 1]; 401 int asize, ref, size; 402 char c, *text, *op, *sp; 403 404 c = *p++; /* Terminator character */ 405 if (c == '\0') 406 return (NULL); 407 408 s->maxbref = 0; 409 s->linenum = linenum; 410 asize = 2 * _POSIX2_LINE_MAX + 1; 411 text = xmalloc(asize); 412 size = 0; 413 do { 414 op = sp = text + size; 415 for (; *p; p++) { 416 if (*p == '\\') { 417 p++; 418 if (strchr("123456789", *p) != NULL) { 419 *sp++ = '\\'; 420 ref = *p - '0'; 421 if (s->re != NULL && 422 ref > s->re->re_nsub) 423 err(COMPILE, 424 "\\%c not defined in the RE", *p); 425 if (s->maxbref < ref) 426 s->maxbref = ref; 427 } else if (*p == '&' || *p == '\\') 428 *sp++ = '\\'; 429 } else if (*p == c) { 430 p++; 431 *sp++ = '\0'; 432 size += sp - op; 433 s->new = xrealloc(text, size); 434 return (p); 435 } else if (*p == '\n') { 436 err(COMPILE, 437 "unescaped newline inside substitute pattern"); 438 /* NOTREACHED */ 439 } 440 *sp++ = *p; 441 } 442 size += sp - op; 443 if (asize - size < _POSIX2_LINE_MAX + 1) { 444 asize *= 2; 445 text = xmalloc(asize); 446 } 447 } while (cu_fgets(p = lbuf, sizeof(lbuf))); 448 err(COMPILE, "unterminated substitute in regular expression"); 449 /* NOTREACHED */ 450 } 451 452 /* 453 * Compile the flags of the s command 454 */ 455 static char * 456 compile_flags(p, s) 457 char *p; 458 struct s_subst *s; 459 { 460 int gn; /* True if we have seen g or n */ 461 char wfile[_POSIX2_LINE_MAX + 1], *q; 462 463 s->n = 1; /* Default */ 464 s->p = 0; 465 s->wfile = NULL; 466 s->wfd = -1; 467 for (gn = 0;;) { 468 EATSPACE(); /* EXTENSION */ 469 switch (*p) { 470 case 'g': 471 if (gn) 472 err(COMPILE, 473 "more than one number or 'g' in substitute flags"); 474 gn = 1; 475 s->n = 0; 476 break; 477 case '\0': 478 case '\n': 479 case ';': 480 return (p); 481 case 'p': 482 s->p = 1; 483 break; 484 case '1': case '2': case '3': 485 case '4': case '5': case '6': 486 case '7': case '8': case '9': 487 if (gn) 488 err(COMPILE, 489 "more than one number or 'g' in substitute flags"); 490 gn = 1; 491 /* XXX Check for overflow */ 492 s->n = (int)strtol(p, &p, 10); 493 break; 494 case 'w': 495 p++; 496 #ifdef HISTORIC_PRACTICE 497 if (*p != ' ') { 498 err(WARNING, "space missing before w wfile"); 499 return (p); 500 } 501 #endif 502 EATSPACE(); 503 q = wfile; 504 while (*p) { 505 if (*p == '\n') 506 break; 507 *q++ = *p++; 508 } 509 *q = '\0'; 510 if (q == wfile) 511 err(COMPILE, "no wfile specified"); 512 s->wfile = strdup(wfile); 513 if (!aflag && (s->wfd = open(wfile, 514 O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, 515 DEFFILEMODE)) == -1) 516 err(FATAL, "%s: %s\n", wfile, strerror(errno)); 517 return (p); 518 default: 519 err(COMPILE, 520 "bad flag in substitute command: '%c'", *p); 521 break; 522 } 523 p++; 524 } 525 } 526 527 /* 528 * Compile a translation set of strings into a lookup table. 529 */ 530 static char * 531 compile_tr(p, transtab) 532 char *p; 533 char **transtab; 534 { 535 int i; 536 char *lt, *op, *np; 537 char old[_POSIX2_LINE_MAX + 1]; 538 char new[_POSIX2_LINE_MAX + 1]; 539 540 if (*p == '\0' || *p == '\\') 541 err(COMPILE, 542 "transform pattern can not be delimited by newline or backslash"); 543 p = compile_delimited(p, old); 544 if (p == NULL) { 545 err(COMPILE, "unterminated transform source string"); 546 return (NULL); 547 } 548 p = compile_delimited(--p, new); 549 if (p == NULL) { 550 err(COMPILE, "unterminated transform target string"); 551 return (NULL); 552 } 553 EATSPACE(); 554 if (strlen(new) != strlen(old)) { 555 err(COMPILE, "transform strings are not the same length"); 556 return (NULL); 557 } 558 /* We assume characters are 8 bits */ 559 lt = xmalloc(UCHAR_MAX); 560 for (i = 0; i <= UCHAR_MAX; i++) 561 lt[i] = (char)i; 562 for (op = old, np = new; *op; op++, np++) 563 lt[(u_char)*op] = *np; 564 *transtab = lt; 565 return (p); 566 } 567 568 /* 569 * Compile the text following an a or i command. 570 */ 571 static char * 572 compile_text() 573 { 574 int asize, size; 575 char *text, *p, *op, *s; 576 char lbuf[_POSIX2_LINE_MAX + 1]; 577 578 asize = 2 * _POSIX2_LINE_MAX + 1; 579 text = xmalloc(asize); 580 size = 0; 581 while (cu_fgets(lbuf, sizeof(lbuf))) { 582 op = s = text + size; 583 p = lbuf; 584 EATSPACE(); 585 for (; *p; p++) { 586 if (*p == '\\') 587 p++; 588 *s++ = *p; 589 } 590 size += s - op; 591 if (p[-2] != '\\') { 592 *s = '\0'; 593 break; 594 } 595 if (asize - size < _POSIX2_LINE_MAX + 1) { 596 asize *= 2; 597 text = xmalloc(asize); 598 } 599 } 600 return (xrealloc(text, size + 1)); 601 } 602 603 /* 604 * Get an address and return a pointer to the first character after 605 * it. Fill the structure pointed to according to the address. 606 */ 607 static char * 608 compile_addr(p, a) 609 char *p; 610 struct s_addr *a; 611 { 612 char *end; 613 614 switch (*p) { 615 case '\\': /* Context address */ 616 ++p; 617 /* FALLTHROUGH */ 618 case '/': /* Context address */ 619 p = compile_re(p, &a->u.r); 620 if (p == NULL) 621 err(COMPILE, "unterminated regular expression"); 622 a->type = AT_RE; 623 return (p); 624 625 case '$': /* Last line */ 626 a->type = AT_LAST; 627 return (p + 1); 628 /* Line number */ 629 case '0': case '1': case '2': case '3': case '4': 630 case '5': case '6': case '7': case '8': case '9': 631 a->type = AT_LINE; 632 a->u.l = strtol(p, &end, 10); 633 return (end); 634 default: 635 err(COMPILE, "expected context address"); 636 return (NULL); 637 } 638 } 639 640 /* 641 * Return a copy of all the characters up to \n or \0 642 */ 643 static char * 644 duptoeol(s) 645 register char *s; 646 { 647 size_t len; 648 char *start; 649 650 for (start = s; *s != '\0' && *s != '\n'; ++s); 651 *s = '\0'; 652 len = s - start + 1; 653 return (memmove(xmalloc(len), start, len)); 654 } 655 656 /* 657 * Find the label contained in the command l in the command linked list cp. 658 * L is excluded from the search. Return NULL if not found. 659 */ 660 static struct s_command * 661 findlabel(l, cp) 662 struct s_command *l, *cp; 663 { 664 struct s_command *r; 665 666 for (; cp; cp = cp->next) 667 if (cp->code == ':' && cp != l && strcmp(l->t, cp->t) == 0) 668 return (cp); 669 else if (cp->code == '{' && (r = findlabel(l, cp->u.c))) 670 return (r); 671 return (NULL); 672 } 673 674 /* 675 * Convert goto label names to addresses. 676 * Detect duplicate labels. 677 * Set appendnum to the number of a and r commands in the script. 678 * Free the memory used by labels in b and t commands (but not by :) 679 * Root is a pointer to the script linked list; cp points to the 680 * search start. 681 * TODO: Remove } nodes 682 */ 683 static void 684 fixuplabel(root, cp, end) 685 struct s_command *root, *cp, *end; 686 { 687 struct s_command *cp2; 688 689 for (; cp != end; cp = cp->next) 690 switch (cp->code) { 691 case ':': 692 if (findlabel(cp, root)) 693 err(COMPILE2, "duplicate label %s", cp->t); 694 break; 695 case 'a': 696 case 'r': 697 appendnum++; 698 break; 699 case 'b': 700 case 't': 701 if (cp->t == NULL) { 702 cp->u.c = NULL; 703 break; 704 } 705 if ((cp2 = findlabel(cp, root)) == NULL) 706 err(COMPILE2, "undefined label '%s'", cp->t); 707 free(cp->t); 708 cp->u.c = cp2; 709 break; 710 case '{': 711 fixuplabel(root, cp->u.c, cp->next); 712 break; 713 } 714 } 715