| 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 | * %sccs.include.redist.c% |
| 10 | */ |
| 11 | |
| 12 | #ifndef lint |
| 13 | static char sccsid[] = "@(#)compile.c 5.2 (Berkeley) %G%"; |
| 14 | #endif /* not lint */ |
| 15 | |
| 16 | #include <sys/types.h> |
| 17 | #include <sys/stat.h> |
| 18 | |
| 19 | #include <ctype.h> |
| 20 | #include <errno.h> |
| 21 | #include <fcntl.h> |
| 22 | #include <limits.h> |
| 23 | #include <regex.h> |
| 24 | #include <stdio.h> |
| 25 | #include <stdlib.h> |
| 26 | #include <string.h> |
| 27 | |
| 28 | #include "defs.h" |
| 29 | #include "extern.h" |
| 30 | |
| 31 | static char *compile_addr __P((char *, struct s_addr *)); |
| 32 | static char *compile_delimited __P((char *, char *)); |
| 33 | static char *compile_flags __P((char *, struct s_subst *)); |
| 34 | static char *compile_re __P((char *, regex_t *, int)); |
| 35 | static char *compile_subst __P((char *, char **, size_t)); |
| 36 | static char *compile_text __P((void)); |
| 37 | static char *compile_tr __P((char *, char **)); |
| 38 | static struct s_command |
| 39 | **compile_stream __P((char *, struct s_command **, char *)); |
| 40 | static char *duptoeol __P((char *)); |
| 41 | static struct s_command |
| 42 | *findlabel __P((struct s_command *, struct s_command *)); |
| 43 | static void fixuplabel __P((struct s_command *, struct s_command *)); |
| 44 | |
| 45 | /* |
| 46 | * Command specification. This is used to drive the command parser. |
| 47 | */ |
| 48 | struct s_format { |
| 49 | char code; /* Command code */ |
| 50 | int naddr; /* Number of address args */ |
| 51 | enum e_args args; /* Argument type */ |
| 52 | }; |
| 53 | |
| 54 | static struct s_format cmd_fmts[] = { |
| 55 | {'{', 2, GROUP}, |
| 56 | {'a', 1, TEXT}, |
| 57 | {'b', 2, BRANCH}, |
| 58 | {'c', 2, TEXT}, |
| 59 | {'d', 2, EMPTY}, |
| 60 | {'D', 2, EMPTY}, |
| 61 | {'g', 2, EMPTY}, |
| 62 | {'G', 2, EMPTY}, |
| 63 | {'h', 2, EMPTY}, |
| 64 | {'H', 2, EMPTY}, |
| 65 | {'i', 1, TEXT}, |
| 66 | {'l', 2, EMPTY}, |
| 67 | {'n', 2, EMPTY}, |
| 68 | {'N', 2, EMPTY}, |
| 69 | {'p', 2, EMPTY}, |
| 70 | {'P', 2, EMPTY}, |
| 71 | {'q', 1, EMPTY}, |
| 72 | {'r', 1, RFILE}, |
| 73 | {'s', 2, SUBST}, |
| 74 | {'t', 2, BRANCH}, |
| 75 | {'w', 2, WFILE}, |
| 76 | {'x', 2, EMPTY}, |
| 77 | {'y', 2, TR}, |
| 78 | {'!', 2, NONSEL}, |
| 79 | {':', 0, LABEL}, |
| 80 | {'#', 0, COMMENT}, |
| 81 | {'=', 1, EMPTY}, |
| 82 | {'\0', 0, COMMENT}, |
| 83 | }; |
| 84 | |
| 85 | /* The compiled program */ |
| 86 | struct s_command *prog; |
| 87 | |
| 88 | /* |
| 89 | * Compile the program into prog. |
| 90 | * Initialise appends |
| 91 | */ |
| 92 | void |
| 93 | compile() |
| 94 | { |
| 95 | *compile_stream(NULL, &prog, NULL) = NULL; |
| 96 | fixuplabel(prog, prog); |
| 97 | appends = xmalloc(sizeof(struct s_appends) * appendnum); |
| 98 | } |
| 99 | |
| 100 | #define EATSPACE() do { \ |
| 101 | if (p) \ |
| 102 | while (*p && isascii(*p) && isspace(*p)) \ |
| 103 | p++; \ |
| 104 | } while (0) |
| 105 | |
| 106 | static struct s_command ** |
| 107 | compile_stream(terminator, link, p) |
| 108 | char *terminator; |
| 109 | struct s_command **link; |
| 110 | register char *p; |
| 111 | { |
| 112 | static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */ |
| 113 | struct s_command *cmd, *cmd2; |
| 114 | struct s_format *fp; |
| 115 | int naddr; /* Number of addresses */ |
| 116 | |
| 117 | if (p != NULL) |
| 118 | goto semicolon; |
| 119 | for (;;) { |
| 120 | if ((p = cu_fgets(lbuf, sizeof(lbuf))) == NULL) { |
| 121 | if (terminator != NULL) |
| 122 | err(COMPILE, "unexpected EOF (pending }'s)"); |
| 123 | return (link); |
| 124 | } |
| 125 | |
| 126 | semicolon: EATSPACE(); |
| 127 | if (p && (*p == '#' || *p == '\0')) |
| 128 | continue; |
| 129 | if (*p == '}') { |
| 130 | if (terminator == NULL) |
| 131 | err(COMPILE, "unexpected }"); |
| 132 | return (link); |
| 133 | } |
| 134 | *link = cmd = xmalloc(sizeof(struct s_command)); |
| 135 | link = &cmd->next; |
| 136 | cmd->nonsel = cmd->inrange = 0; |
| 137 | /* First parse the addresses */ |
| 138 | naddr = 0; |
| 139 | cmd->a1 = cmd->a2 = NULL; |
| 140 | |
| 141 | /* Valid characters to start an address */ |
| 142 | #define addrchar(c) (strchr("0123456789/\\$", (c))) |
| 143 | if (addrchar(*p)) { |
| 144 | naddr++; |
| 145 | cmd->a1 = xmalloc(sizeof(struct s_addr)); |
| 146 | p = compile_addr(p, cmd->a1); |
| 147 | EATSPACE(); /* EXTENSION */ |
| 148 | if (*p == ',') { |
| 149 | naddr++; |
| 150 | p++; |
| 151 | EATSPACE(); /* EXTENSION */ |
| 152 | cmd->a2 = xmalloc(sizeof(struct s_addr)); |
| 153 | p = compile_addr(p, cmd->a2); |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | nonsel: /* Now parse the command */ |
| 158 | EATSPACE(); |
| 159 | if (!*p) |
| 160 | err(COMPILE, "command expected"); |
| 161 | cmd->code = *p; |
| 162 | for (fp = cmd_fmts; fp->code; fp++) |
| 163 | if (fp->code == *p) |
| 164 | break; |
| 165 | if (!fp->code) |
| 166 | err(COMPILE, "invalid command code %c", *p); |
| 167 | if (naddr > fp->naddr) |
| 168 | err(COMPILE, |
| 169 | "command %c expects up to %d address(es), found %d", *p, fp->naddr, naddr); |
| 170 | switch (fp->args) { |
| 171 | case NONSEL: /* ! */ |
| 172 | cmd->nonsel = ! cmd->nonsel; |
| 173 | p++; |
| 174 | goto nonsel; |
| 175 | case GROUP: /* { */ |
| 176 | p++; |
| 177 | EATSPACE(); |
| 178 | if (!*p) |
| 179 | p = NULL; |
| 180 | cmd2 = xmalloc(sizeof(struct s_command)); |
| 181 | cmd2->code = '}'; |
| 182 | *compile_stream("}", &cmd->u.c, p) = cmd2; |
| 183 | cmd->next = cmd2; |
| 184 | link = &cmd2->next; |
| 185 | break; |
| 186 | case EMPTY: /* d D g G h H l n N p P q x = \0 */ |
| 187 | p++; |
| 188 | EATSPACE(); |
| 189 | if (*p == ';') { |
| 190 | p++; |
| 191 | link = &cmd->next; |
| 192 | goto semicolon; |
| 193 | } |
| 194 | if (*p) |
| 195 | err(COMPILE, |
| 196 | "extra characters at the end of %c command", cmd->code); |
| 197 | break; |
| 198 | case TEXT: /* a c i */ |
| 199 | p++; |
| 200 | EATSPACE(); |
| 201 | if (*p != '\\') |
| 202 | err(COMPILE, |
| 203 | "command %c expects \\ followed by text", cmd->code); |
| 204 | p++; |
| 205 | EATSPACE(); |
| 206 | if (*p) |
| 207 | err(COMPILE, |
| 208 | "extra characters after \\ at the end of %c command", cmd->code); |
| 209 | cmd->t = compile_text(); |
| 210 | break; |
| 211 | case COMMENT: /* \0 # */ |
| 212 | break; |
| 213 | case WFILE: /* w */ |
| 214 | p++; |
| 215 | EATSPACE(); |
| 216 | if (*p == '\0') |
| 217 | err(COMPILE, "filename expected"); |
| 218 | cmd->t = duptoeol(p); |
| 219 | if (aflag) |
| 220 | cmd->u.fd = -1; |
| 221 | else if ((cmd->u.fd = open(p, |
| 222 | O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, |
| 223 | DEFFILEMODE)) == -1) |
| 224 | err(FATAL, "%s: %s\n", p, strerror(errno)); |
| 225 | break; |
| 226 | case RFILE: /* r */ |
| 227 | p++; |
| 228 | EATSPACE(); |
| 229 | if (*p == '\0') |
| 230 | err(COMPILE, "filename expected"); |
| 231 | else |
| 232 | cmd->t = duptoeol(p); |
| 233 | break; |
| 234 | case BRANCH: /* b t */ |
| 235 | p++; |
| 236 | EATSPACE(); |
| 237 | if (*p == '\0') |
| 238 | cmd->t = NULL; |
| 239 | else |
| 240 | cmd->t = duptoeol(p); |
| 241 | break; |
| 242 | case LABEL: /* : */ |
| 243 | p++; |
| 244 | EATSPACE(); |
| 245 | cmd->t = duptoeol(p); |
| 246 | if (strlen(p) == 0) |
| 247 | err(COMPILE, "empty label"); |
| 248 | break; |
| 249 | case SUBST: /* s */ |
| 250 | p++; |
| 251 | if (*p == '\0' || *p == '\\') |
| 252 | err(COMPILE, |
| 253 | "substitute pattern can not be delimited by newline or backslash"); |
| 254 | cmd->u.s = xmalloc(sizeof(struct s_subst)); |
| 255 | p = compile_re(p, &cmd->u.s->re, 0); |
| 256 | if (p == NULL) |
| 257 | err(COMPILE, "unterminated substitute pattern"); |
| 258 | cmd->u.s->pmatch = xmalloc((cmd->u.s->re.re_nsub + 1) * |
| 259 | sizeof(regmatch_t)); |
| 260 | p--; |
| 261 | p = compile_subst(p, |
| 262 | &cmd->u.s->new, cmd->u.s->re.re_nsub); |
| 263 | if (p == NULL) |
| 264 | err(COMPILE, |
| 265 | "unterminated substitute replace in regular expression"); |
| 266 | p = compile_flags(p, cmd->u.s); |
| 267 | EATSPACE(); |
| 268 | if (*p == ';') { |
| 269 | p++; |
| 270 | link = &cmd->next; |
| 271 | goto semicolon; |
| 272 | } |
| 273 | break; |
| 274 | case TR: /* y */ |
| 275 | p++; |
| 276 | p = compile_tr(p, (char **)&cmd->u.y); |
| 277 | EATSPACE(); |
| 278 | if (*p == ';') { |
| 279 | p++; |
| 280 | link = &cmd->next; |
| 281 | goto semicolon; |
| 282 | } |
| 283 | if (*p) |
| 284 | err(COMPILE, |
| 285 | "extra text at the end of a transform command"); |
| 286 | break; |
| 287 | } |
| 288 | } |
| 289 | } |
| 290 | |
| 291 | /* |
| 292 | * Get a delimited string. P points to the delimeter of the string; d points |
| 293 | * to a buffer area. Newline and delimiter escapes are processed; other |
| 294 | * escapes are ignored. |
| 295 | * |
| 296 | * Returns a pointer to the first character after the final delimiter or NULL |
| 297 | * in the case of a non-terminated string. The character array d is filled |
| 298 | * with the processed string. |
| 299 | */ |
| 300 | static char * |
| 301 | compile_delimited(p, d) |
| 302 | char *p, *d; |
| 303 | { |
| 304 | char c; |
| 305 | |
| 306 | c = *p++; |
| 307 | if (c == '\0') |
| 308 | return (NULL); |
| 309 | else if (c == '\\') |
| 310 | err(COMPILE, "\\ can not be used as a string delimiter"); |
| 311 | else if (c == '\n') |
| 312 | err(COMPILE, "newline can not be used as a string delimiter"); |
| 313 | while (*p) { |
| 314 | if (*p == '\\' && p[1] == c) |
| 315 | p++; |
| 316 | else if (*p == '\\' && p[1] == 'n') { |
| 317 | *d++ = '\n'; |
| 318 | p += 2; |
| 319 | continue; |
| 320 | } else if (*p == c) { |
| 321 | *d = '\0'; |
| 322 | return (p + 1); |
| 323 | } |
| 324 | *d++ = *p++; |
| 325 | } |
| 326 | return (NULL); |
| 327 | } |
| 328 | |
| 329 | /* |
| 330 | * Get a regular expression. P points to the delimeter of the regular |
| 331 | * expression; d points a regexp pointer. Newline and delimiter escapes |
| 332 | * are processed; other escapes are ignored. |
| 333 | * Returns a pointer to the first character after the final delimiter |
| 334 | * or NULL in the case of a non terminated regular expression. |
| 335 | * The regexp pointer is set to the compiled regular expression. |
| 336 | * Cflags are passed to regcomp. |
| 337 | */ |
| 338 | static char * |
| 339 | compile_re(p, rep, cflags) |
| 340 | char *p; |
| 341 | regex_t *rep; |
| 342 | int cflags; |
| 343 | { |
| 344 | int eval; |
| 345 | char re[_POSIX2_LINE_MAX + 1]; |
| 346 | |
| 347 | p = compile_delimited(p, re); |
| 348 | if (p && (eval = regcomp(rep, re, cflags)) != 0) |
| 349 | err(COMPILE, "RE error: %s", strregerror(eval, rep)); |
| 350 | return (p); |
| 351 | } |
| 352 | |
| 353 | /* |
| 354 | * Compile the substitution string of a regular expression and set res to |
| 355 | * point to a saved copy of it. Nsub is the number of parenthesized regular |
| 356 | * expressions. |
| 357 | */ |
| 358 | static char * |
| 359 | compile_subst(p, res, nsub) |
| 360 | char *p, **res; |
| 361 | size_t nsub; |
| 362 | { |
| 363 | static char lbuf[_POSIX2_LINE_MAX + 1]; |
| 364 | int asize, size; |
| 365 | char c, *text, *op, *s; |
| 366 | |
| 367 | c = *p++; /* Terminator character */ |
| 368 | if (c == '\0') |
| 369 | return (NULL); |
| 370 | |
| 371 | asize = 2 * _POSIX2_LINE_MAX + 1; |
| 372 | text = xmalloc(asize); |
| 373 | size = 0; |
| 374 | do { |
| 375 | op = s = text + size; |
| 376 | for (; *p; p++) { |
| 377 | if (*p == '\\') { |
| 378 | p++; |
| 379 | if (strchr("123456789", *p) != NULL) { |
| 380 | *s++ = '\\'; |
| 381 | if (*p - '1' > nsub) |
| 382 | err(COMPILE, |
| 383 | "\\%c not defined in regular expression (use \\1-\\%d)", *p, nsub + 1); |
| 384 | } else if (*p == '&') |
| 385 | *s++ = '\\'; |
| 386 | } else if (*p == c) { |
| 387 | p++; |
| 388 | *s++ = '\0'; |
| 389 | size += s - op; |
| 390 | *res = xrealloc(text, size); |
| 391 | return (p); |
| 392 | } else if (*p == '\n') { |
| 393 | err(COMPILE, |
| 394 | "unescaped newline inside substitute pattern"); |
| 395 | return (NULL); |
| 396 | } |
| 397 | *s++ = *p; |
| 398 | } |
| 399 | size += s - op; |
| 400 | if (asize - size < _POSIX2_LINE_MAX + 1) { |
| 401 | asize *= 2; |
| 402 | text = xmalloc(asize); |
| 403 | } |
| 404 | } while (cu_fgets(p = lbuf, sizeof(lbuf))); |
| 405 | err(COMPILE, "unterminated substitute pattern"); |
| 406 | return (NULL); |
| 407 | } |
| 408 | |
| 409 | /* |
| 410 | * Compile the flags of the s command |
| 411 | */ |
| 412 | static char * |
| 413 | compile_flags(p, s) |
| 414 | char *p; |
| 415 | struct s_subst *s; |
| 416 | { |
| 417 | int gn; /* True if we have seen g or n */ |
| 418 | char wfile[_POSIX2_LINE_MAX + 1], *q; |
| 419 | |
| 420 | s->n = 1; /* Default */ |
| 421 | s->p = 0; |
| 422 | s->wfile = NULL; |
| 423 | s->wfd = -1; |
| 424 | for (gn = 0;;) { |
| 425 | EATSPACE(); /* EXTENSION */ |
| 426 | switch (*p) { |
| 427 | case 'g': |
| 428 | if (gn) |
| 429 | err(COMPILE, |
| 430 | "more than one number or 'g' in substitute flags"); |
| 431 | gn = 1; |
| 432 | s->n = 0; |
| 433 | break; |
| 434 | case '\0': |
| 435 | case '\n': |
| 436 | case ';': |
| 437 | return (p); |
| 438 | case 'p': |
| 439 | s->p = 1; |
| 440 | break; |
| 441 | case '1': case '2': case '3': |
| 442 | case '4': case '5': case '6': |
| 443 | case '7': case '8': case '9': |
| 444 | if (gn) |
| 445 | err(COMPILE, |
| 446 | "more than one number or 'g' in substitute flags"); |
| 447 | gn = 1; |
| 448 | /* XXX Check for overflow */ |
| 449 | s->n = (int)strtol(p, &p, 10); |
| 450 | break; |
| 451 | case 'w': |
| 452 | p++; |
| 453 | #ifdef HISTORIC_PRACTICE |
| 454 | if (*p != ' ') { |
| 455 | err(WARNING, "space missing before w wfile"); |
| 456 | return (p); |
| 457 | } |
| 458 | #endif |
| 459 | EATSPACE(); |
| 460 | q = wfile; |
| 461 | while (*p) { |
| 462 | if (*p == '\n') |
| 463 | break; |
| 464 | *q++ = *p++; |
| 465 | } |
| 466 | *q = '\0'; |
| 467 | if (q == wfile) |
| 468 | err(COMPILE, "no wfile specified"); |
| 469 | s->wfile = strdup(wfile); |
| 470 | if (!aflag && (s->wfd = open(wfile, |
| 471 | O_WRONLY|O_APPEND|O_CREAT|O_TRUNC, |
| 472 | DEFFILEMODE)) == -1) |
| 473 | err(FATAL, "%s: %s\n", wfile, strerror(errno)); |
| 474 | return (p); |
| 475 | default: |
| 476 | err(COMPILE, |
| 477 | "bad flag in substitute command: '%c'", *p); |
| 478 | break; |
| 479 | } |
| 480 | p++; |
| 481 | } |
| 482 | } |
| 483 | |
| 484 | /* |
| 485 | * Compile a translation set of strings into a lookup table. |
| 486 | */ |
| 487 | static char * |
| 488 | compile_tr(p, transtab) |
| 489 | char *p; |
| 490 | char **transtab; |
| 491 | { |
| 492 | int i; |
| 493 | char *lt, *op, *np; |
| 494 | char old[_POSIX2_LINE_MAX + 1]; |
| 495 | char new[_POSIX2_LINE_MAX + 1]; |
| 496 | |
| 497 | if (*p == '\0' || *p == '\\') |
| 498 | err(COMPILE, |
| 499 | "transform pattern can not be delimited by newline or backslash"); |
| 500 | p = compile_delimited(p, old); |
| 501 | if (p == NULL) { |
| 502 | err(COMPILE, "unterminated transform source string"); |
| 503 | return (NULL); |
| 504 | } |
| 505 | p = compile_delimited(--p, new); |
| 506 | if (p == NULL) { |
| 507 | err(COMPILE, "unterminated transform target string"); |
| 508 | return (NULL); |
| 509 | } |
| 510 | EATSPACE(); |
| 511 | if (strlen(new) != strlen(old)) { |
| 512 | err(COMPILE, "transform strings are not the same length"); |
| 513 | return (NULL); |
| 514 | } |
| 515 | /* We assume characters are 8 bits */ |
| 516 | lt = xmalloc(UCHAR_MAX); |
| 517 | for (i = 0; i <= UCHAR_MAX; i++) |
| 518 | lt[i] = (char)i; |
| 519 | for (op = old, np = new; *op; op++, np++) |
| 520 | lt[(u_char)*op] = *np; |
| 521 | *transtab = lt; |
| 522 | return (p); |
| 523 | } |
| 524 | |
| 525 | /* |
| 526 | * Compile the text following an a or i command. |
| 527 | */ |
| 528 | static char * |
| 529 | compile_text() |
| 530 | { |
| 531 | int asize, size; |
| 532 | char *text, *p, *op, *s; |
| 533 | char lbuf[_POSIX2_LINE_MAX + 1]; |
| 534 | |
| 535 | asize = 2 * _POSIX2_LINE_MAX + 1; |
| 536 | text = xmalloc(asize); |
| 537 | size = 0; |
| 538 | while (cu_fgets(lbuf, sizeof(lbuf))) { |
| 539 | op = s = text + size; |
| 540 | p = lbuf; |
| 541 | EATSPACE(); |
| 542 | for (; *p; p++) { |
| 543 | if (*p == '\\') |
| 544 | p++; |
| 545 | *s++ = *p; |
| 546 | } |
| 547 | size += s - op; |
| 548 | if (p[-2] != '\\') { |
| 549 | *s = '\0'; |
| 550 | break; |
| 551 | } |
| 552 | if (asize - size < _POSIX2_LINE_MAX + 1) { |
| 553 | asize *= 2; |
| 554 | text = xmalloc(asize); |
| 555 | } |
| 556 | } |
| 557 | return (xrealloc(text, size + 1)); |
| 558 | } |
| 559 | |
| 560 | /* |
| 561 | * Get an address and return a pointer to the first character after |
| 562 | * it. Fill the structure pointed to according to the address. |
| 563 | */ |
| 564 | static char * |
| 565 | compile_addr(p, a) |
| 566 | char *p; |
| 567 | struct s_addr *a; |
| 568 | { |
| 569 | regex_t *re; |
| 570 | char *end; |
| 571 | |
| 572 | switch (*p) { |
| 573 | case '\\': /* Context address */ |
| 574 | re = xmalloc(sizeof(regex_t)); |
| 575 | a->u.r = re; |
| 576 | p = compile_re(p + 1, re, REG_NOSUB); |
| 577 | if (p == NULL) |
| 578 | err(COMPILE, "unterminated regular expression"); |
| 579 | a->type = AT_RE; |
| 580 | return (p); |
| 581 | case '/': /* Context address */ |
| 582 | re = xmalloc(sizeof(regex_t)); |
| 583 | a->u.r = re; |
| 584 | p = compile_re(p, a->u.r, REG_NOSUB); |
| 585 | if (p == NULL) |
| 586 | err(COMPILE, "unterminated regular expression"); |
| 587 | a->type = AT_RE; |
| 588 | return (p); |
| 589 | case '$': /* Last line */ |
| 590 | a->type = AT_LAST; |
| 591 | return (p + 1); |
| 592 | /* Line number */ |
| 593 | case '0': case '1': case '2': case '3': case '4': |
| 594 | case '5': case '6': case '7': case '8': case '9': |
| 595 | a->type = AT_LINE; |
| 596 | a->u.l = strtol(p, &end, 10); |
| 597 | return (end); |
| 598 | default: |
| 599 | err(COMPILE, "expected context address"); |
| 600 | return (NULL); |
| 601 | } |
| 602 | } |
| 603 | |
| 604 | /* |
| 605 | * Return a copy of all the characters up to \n or \0 |
| 606 | */ |
| 607 | static char * |
| 608 | duptoeol(s) |
| 609 | register char *s; |
| 610 | { |
| 611 | size_t len; |
| 612 | char *start; |
| 613 | |
| 614 | for (start = s; *s != '\0' && *s != '\n'; ++s); |
| 615 | *s = '\0'; |
| 616 | len = s - start + 1; |
| 617 | return (memmove(xmalloc(len), start, len)); |
| 618 | } |
| 619 | |
| 620 | /* |
| 621 | * Find the label contained in the command l in the command linked list cp. |
| 622 | * L is excluded from the search. Return NULL if not found. |
| 623 | */ |
| 624 | static struct s_command * |
| 625 | findlabel(l, cp) |
| 626 | struct s_command *l, *cp; |
| 627 | { |
| 628 | struct s_command *r; |
| 629 | |
| 630 | for (; cp; cp = cp->next) |
| 631 | if (cp->code == ':' && cp != l && strcmp(l->t, cp->t) == 0) |
| 632 | return (cp); |
| 633 | else if (cp->code == '{' && (r = findlabel(l, cp->u.c))) |
| 634 | return (r); |
| 635 | return (NULL); |
| 636 | } |
| 637 | |
| 638 | /* |
| 639 | * Convert goto label names to addresses. |
| 640 | * Detect duplicate labels. |
| 641 | * Set appendnum to the number of a and r commands in the script. |
| 642 | * Free the memory used by labels in b and t commands (but not by :) |
| 643 | * Root is a pointer to the script linked list; cp points to the |
| 644 | * search start. |
| 645 | * TODO: Remove } nodes |
| 646 | */ |
| 647 | static void |
| 648 | fixuplabel(root, cp) |
| 649 | struct s_command *root, *cp; |
| 650 | { |
| 651 | struct s_command *cp2; |
| 652 | |
| 653 | for (; cp; cp = cp->next) |
| 654 | switch (cp->code) { |
| 655 | case 'a': |
| 656 | case 'r': |
| 657 | appendnum++; |
| 658 | break; |
| 659 | case 'b': |
| 660 | case 't': |
| 661 | if (cp->t == NULL) { |
| 662 | cp->u.c = NULL; |
| 663 | break; |
| 664 | } |
| 665 | if ((cp2 = findlabel(cp, root)) == NULL) |
| 666 | err(COMPILE2, "undefined label '%s'", cp->t); |
| 667 | free(cp->t); |
| 668 | cp->u.c = cp2; |
| 669 | break; |
| 670 | case '{': |
| 671 | fixuplabel(root, cp->u.c); |
| 672 | break; |
| 673 | case ':': |
| 674 | if (findlabel(cp, root)) |
| 675 | err(COMPILE2, "duplicate label %s", cp->t); |
| 676 | break; |
| 677 | } |
| 678 | } |