usr.bin/sed/compile.c

   1 /*-
   2  * Copyright (c) 1992 Diomidis Spinellis.
   3  * Copyright (c) 1992, 1993
   4  *      The Regents of the University of California.  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  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)compile.c        8.1 (Berkeley) 6/6/93
  34  * $FreeBSD: src/usr.bin/sed/compile.c,v 1.31 2008/02/09 09:12:02 dwmalone Exp $
  35  * $DragonFly: src/usr.bin/sed/compile.c,v 1.4 2008/04/08 13:23:38 swildner Exp $
  36  */
  37
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40
  41 #include <ctype.h>
  42 #include <err.h>
  43 #include <errno.h>
  44 #include <fcntl.h>
  45 #include <limits.h>
  46 #include <regex.h>
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include <string.h>
  50 #include <wchar.h>
  51
  52 #include "defs.h"
  53 #include "extern.h"
  54
  55 #define LHSZ    128
  56 #define LHMASK  (LHSZ - 1)
  57 static struct labhash {
  58         struct  labhash *lh_next;
  59         u_int   lh_hash;
  60         struct  s_command *lh_cmd;
  61         int     lh_ref;
  62 } *labels[LHSZ];
  63
  64 static char      *compile_addr(char *, struct s_addr *);
  65 static char      *compile_ccl(char **, char *);
  66 static char      *compile_delimited(char *, char *);
  67 static char      *compile_flags(char *, struct s_subst *);
  68 static regex_t   *compile_re(char *, int);
  69 static char      *compile_subst(char *, struct s_subst *);
  70 static char      *compile_text(void);
  71 static char      *compile_tr(char *, struct s_tr **);
  72 static struct s_command
  73                 **compile_stream(struct s_command **);
  74 static char      *duptoeol(char *, const char *);
  75 static void       enterlabel(struct s_command *);
  76 static struct s_command
  77                  *findlabel(char *);
  78 static void       fixuplabel(struct s_command *, struct s_command *);
  79 static void       uselabel(void);
  80
  81 /*
  82  * Command specification.  This is used to drive the command parser.
  83  */
  84 struct s_format {
  85         char code;                              /* Command code */
  86         int naddr;                              /* Number of address args */
  87         enum e_args args;                       /* Argument type */
  88 };
  89
  90 static struct s_format cmd_fmts[] = {
  91         {'{', 2, GROUP},
  92         {'}', 0, ENDGROUP},
  93         {'a', 1, TEXT},
  94         {'b', 2, BRANCH},
  95         {'c', 2, TEXT},
  96         {'d', 2, EMPTY},
  97         {'D', 2, EMPTY},
  98         {'g', 2, EMPTY},
  99         {'G', 2, EMPTY},
 100         {'h', 2, EMPTY},
 101         {'H', 2, EMPTY},
 102         {'i', 1, TEXT},
 103         {'l', 2, EMPTY},
 104         {'n', 2, EMPTY},
 105         {'N', 2, EMPTY},
 106         {'p', 2, EMPTY},
 107         {'P', 2, EMPTY},
 108         {'q', 1, EMPTY},
 109         {'r', 1, RFILE},
 110         {'s', 2, SUBST},
 111         {'t', 2, BRANCH},
 112         {'w', 2, WFILE},
 113         {'x', 2, EMPTY},
 114         {'y', 2, TR},
 115         {'!', 2, NONSEL},
 116         {':', 0, LABEL},
 117         {'#', 0, COMMENT},
 118         {'=', 1, EMPTY},
 119         {'\0', 0, COMMENT},
 120 };
 121
 122 /* The compiled program. */
 123 struct s_command *prog;
 124
 125 /*
 126  * Compile the program into prog.
 127  * Initialise appends.
 128  */
 129 void
 130 compile(void)
 131 {
 132         *compile_stream(&prog) = NULL;
 133         fixuplabel(prog, NULL);
 134         uselabel();
 135         if (appendnum == 0)
 136                 appends = NULL;
 137         else if ((appends = malloc(sizeof(struct s_appends) * appendnum)) ==
 138             NULL)
 139                 err(1, "malloc");
 140         if ((match = malloc((maxnsub + 1) * sizeof(regmatch_t))) == NULL)
 141                 err(1, "malloc");
 142 }
 143
 144 #define EATSPACE() do {                                                 \
 145         if (p)                                                          \
 146                 while (*p && isspace((unsigned char)*p))                \
 147                         p++;                                            \
 148         } while (0)
 149
 150 static struct s_command **
 151 compile_stream(struct s_command **link)
 152 {
 153         char *p;
 154         static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */
 155         struct s_command *cmd, *cmd2, *stack;
 156         struct s_format *fp;
 157         char re[_POSIX2_LINE_MAX + 1];
 158         int naddr;                              /* Number of addresses */
 159
 160         stack = 0;
 161         for (;;) {
 162                 if ((p = cu_fgets(lbuf, sizeof(lbuf), NULL)) == NULL) {
 163                         if (stack != 0)
 164                                 errx(1, "%lu: %s: unexpected EOF (pending }'s)",
 165                                                         linenum, fname);
 166                         return (link);
 167                 }
 168
 169 semicolon:      EATSPACE();
 170                 if (p) {
 171                         if (*p == '#' || *p == '\0')
 172                                 continue;
 173                         else if (*p == ';') {
 174                                 p++;
 175                                 goto semicolon;
 176                         }
 177                 }
 178                 if ((*link = cmd = malloc(sizeof(struct s_command))) == NULL)
 179                         err(1, "malloc");
 180                 link = &cmd->next;
 181                 cmd->nonsel = cmd->inrange = 0;
 182                 /* First parse the addresses */
 183                 naddr = 0;
 184
 185 /* Valid characters to start an address */
 186 #define addrchar(c)     (strchr("0123456789/\\$", (c)))
 187                 if (addrchar(*p)) {
 188                         naddr++;
 189                         if ((cmd->a1 = malloc(sizeof(struct s_addr))) == NULL)
 190                                 err(1, "malloc");
 191                         p = compile_addr(p, cmd->a1);
 192                         EATSPACE();                             /* EXTENSION */
 193                         if (*p == ',') {
 194                                 p++;
 195                                 EATSPACE();                     /* EXTENSION */
 196                                 naddr++;
 197                                 if ((cmd->a2 = malloc(sizeof(struct s_addr)))
 198                                     == NULL)
 199                                         err(1, "malloc");
 200                                 p = compile_addr(p, cmd->a2);
 201                                 EATSPACE();
 202                         } else
 203                                 cmd->a2 = 0;
 204                 } else
 205                         cmd->a1 = cmd->a2 = 0;
 206
 207 nonsel:         /* Now parse the command */
 208                 if (!*p)
 209                         errx(1, "%lu: %s: command expected", linenum, fname);
 210                 cmd->code = *p;
 211                 for (fp = cmd_fmts; fp->code; fp++)
 212                         if (fp->code == *p)
 213                                 break;
 214                 if (!fp->code)
 215                         errx(1, "%lu: %s: invalid command code %c", linenum, fname, *p);
 216                 if (naddr > fp->naddr)
 217                         errx(1,
 218                                 "%lu: %s: command %c expects up to %d address(es), found %d",
 219                                 linenum, fname, *p, fp->naddr, naddr);
 220                 switch (fp->args) {
 221                 case NONSEL:                    /* ! */
 222                         p++;
 223                         EATSPACE();
 224                         cmd->nonsel = ! cmd->nonsel;
 225                         goto nonsel;
 226                 case GROUP:                     /* { */
 227                         p++;
 228                         EATSPACE();
 229                         cmd->next = stack;
 230                         stack = cmd;
 231                         link = &cmd->u.c;
 232                         if (*p)
 233                                 goto semicolon;
 234                         break;
 235                 case ENDGROUP:
 236                         /*
 237                          * Short-circuit command processing, since end of
 238                          * group is really just a noop.
 239                          */
 240                         cmd->nonsel = 1;
 241                         if (stack == 0)
 242                                 errx(1, "%lu: %s: unexpected }", linenum, fname);
 243                         cmd2 = stack;
 244                         stack = cmd2->next;
 245                         cmd2->next = cmd;
 246                         /*FALLTHROUGH*/
 247                 case EMPTY:             /* d D g G h H l n N p P q x = \0 */
 248                         p++;
 249                         EATSPACE();
 250                         if (*p == ';') {
 251                                 p++;
 252                                 link = &cmd->next;
 253                                 goto semicolon;
 254                         }
 255                         if (*p)
 256                                 errx(1, "%lu: %s: extra characters at the end of %c command",
 257                                                 linenum, fname, cmd->code);
 258                         break;
 259                 case TEXT:                      /* a c i */
 260                         p++;
 261                         EATSPACE();
 262                         if (*p != '\\')
 263                                 errx(1,
 264 "%lu: %s: command %c expects \\ followed by text", linenum, fname, cmd->code);
 265                         p++;
 266                         EATSPACE();
 267                         if (*p)
 268                                 errx(1,
 269                                 "%lu: %s: extra characters after \\ at the end of %c command",
 270                                 linenum, fname, cmd->code);
 271                         cmd->t = compile_text();
 272                         break;
 273                 case COMMENT:                   /* \0 # */
 274                         break;
 275                 case WFILE:                     /* w */
 276                         p++;
 277                         EATSPACE();
 278                         if (*p == '\0')
 279                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 280                         cmd->t = duptoeol(p, "w command");
 281                         if (aflag)
 282                                 cmd->u.fd = -1;
 283                         else if ((cmd->u.fd = open(p,
 284                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 285                             DEFFILEMODE)) == -1)
 286                                 err(1, "%s", p);
 287                         break;
 288                 case RFILE:                     /* r */
 289                         p++;
 290                         EATSPACE();
 291                         if (*p == '\0')
 292                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 293                         else
 294                                 cmd->t = duptoeol(p, "read command");
 295                         break;
 296                 case BRANCH:                    /* b t */
 297                         p++;
 298                         EATSPACE();
 299                         if (*p == '\0')
 300                                 cmd->t = NULL;
 301                         else
 302                                 cmd->t = duptoeol(p, "branch");
 303                         break;
 304                 case LABEL:                     /* : */
 305                         p++;
 306                         EATSPACE();
 307                         cmd->t = duptoeol(p, "label");
 308                         if (strlen(p) == 0)
 309                                 errx(1, "%lu: %s: empty label", linenum, fname);
 310                         enterlabel(cmd);
 311                         break;
 312                 case SUBST:                     /* s */
 313                         p++;
 314                         if (*p == '\0' || *p == '\\')
 315                                 errx(1,
 316 "%lu: %s: substitute pattern can not be delimited by newline or backslash",
 317                                         linenum, fname);
 318                         if ((cmd->u.s = calloc(1, sizeof(struct s_subst))) == NULL)
 319                                 err(1, "malloc");
 320                         p = compile_delimited(p, re);
 321                         if (p == NULL)
 322                                 errx(1,
 323                                 "%lu: %s: unterminated substitute pattern", linenum, fname);
 324                         --p;
 325                         p = compile_subst(p, cmd->u.s);
 326                         p = compile_flags(p, cmd->u.s);
 327                         if (*re == '\0')
 328                                 cmd->u.s->re = NULL;
 329                         else
 330                                 cmd->u.s->re = compile_re(re, cmd->u.s->icase);
 331                         EATSPACE();
 332                         if (*p == ';') {
 333                                 p++;
 334                                 link = &cmd->next;
 335                                 goto semicolon;
 336                         }
 337                         break;
 338                 case TR:                        /* y */
 339                         p++;
 340                         p = compile_tr(p, &cmd->u.y);
 341                         EATSPACE();
 342                         if (*p == ';') {
 343                                 p++;
 344                                 link = &cmd->next;
 345                                 goto semicolon;
 346                         }
 347                         if (*p)
 348                                 errx(1,
 349 "%lu: %s: extra text at the end of a transform command", linenum, fname);
 350                         break;
 351                 }
 352         }
 353 }
 354
 355 /*
 356  * Get a delimited string.  P points to the delimeter of the string; d points
 357  * to a buffer area.  Newline and delimiter escapes are processed; other
 358  * escapes are ignored.
 359  *
 360  * Returns a pointer to the first character after the final delimiter or NULL
 361  * in the case of a non-terminated string.  The character array d is filled
 362  * with the processed string.
 363  */
 364 static char *
 365 compile_delimited(char *p, char *d)
 366 {
 367         char c;
 368
 369         c = *p++;
 370         if (c == '\0')
 371                 return (NULL);
 372         else if (c == '\\')
 373                 errx(1, "%lu: %s: \\ can not be used as a string delimiter",
 374                                 linenum, fname);
 375         else if (c == '\n')
 376                 errx(1, "%lu: %s: newline can not be used as a string delimiter",
 377                                 linenum, fname);
 378         while (*p) {
 379                 if (*p == '[') {
 380                         if ((d = compile_ccl(&p, d)) == NULL)
 381                                 errx(1, "%lu: %s: unbalanced brackets ([])", linenum, fname);
 382                         continue;
 383                 } else if (*p == '\\' && p[1] == '[') {
 384                         *d++ = *p++;
 385                 } else if (*p == '\\' && p[1] == c)
 386                         p++;
 387                 else if (*p == '\\' && p[1] == 'n') {
 388                         *d++ = '\n';
 389                         p += 2;
 390                         continue;
 391                 } else if (*p == '\\' && p[1] == '\\')
 392                         *d++ = *p++;
 393                 else if (*p == c) {
 394                         *d = '\0';
 395                         return (p + 1);
 396                 }
 397                 *d++ = *p++;
 398         }
 399         return (NULL);
 400 }
 401
 402
 403 /* compile_ccl: expand a POSIX character class */
 404 static char *
 405 compile_ccl(char **sp, char *t)
 406 {
 407         int c, d;
 408         char *s = *sp;
 409
 410         *t++ = *s++;
 411         if (*s == '^')
 412                 *t++ = *s++;
 413         if (*s == ']')
 414                 *t++ = *s++;
 415         for (; *s && (*t = *s) != ']'; s++, t++)
 416                 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) {
 417                         *++t = *++s, t++, s++;
 418                         for (c = *s; (*t = *s) != ']' || c != d; s++, t++)
 419                                 if ((c = *s) == '\0')
 420                                         return NULL;
 421                 } else if (*s == '\\' && s[1] == 'n')
 422                             *t = '\n', s++;
 423         return (*s == ']') ? *sp = ++s, ++t : NULL;
 424 }
 425
 426 /*
 427  * Compiles the regular expression in RE and returns a pointer to the compiled
 428  * regular expression.
 429  * Cflags are passed to regcomp.
 430  */
 431 static regex_t *
 432 compile_re(char *re, int case_insensitive)
 433 {
 434         regex_t *rep;
 435         int eval, flags;
 436
 437
 438         flags = rflags;
 439         if (case_insensitive)
 440                 flags |= REG_ICASE;
 441         if ((rep = malloc(sizeof(regex_t))) == NULL)
 442                 err(1, "malloc");
 443         if ((eval = regcomp(rep, re, flags)) != 0)
 444                 errx(1, "%lu: %s: RE error: %s",
 445                                 linenum, fname, strregerror(eval, rep));
 446         if (maxnsub < rep->re_nsub)
 447                 maxnsub = rep->re_nsub;
 448         return (rep);
 449 }
 450
 451 /*
 452  * Compile the substitution string of a regular expression and set res to
 453  * point to a saved copy of it.  Nsub is the number of parenthesized regular
 454  * expressions.
 455  */
 456 static char *
 457 compile_subst(char *p, struct s_subst *s)
 458 {
 459         static char lbuf[_POSIX2_LINE_MAX + 1];
 460         int asize, size;
 461         u_char ref;
 462         char c, *text, *op, *sp;
 463         int more = 1, sawesc = 0;
 464
 465         c = *p++;                       /* Terminator character */
 466         if (c == '\0')
 467                 return (NULL);
 468
 469         s->maxbref = 0;
 470         s->linenum = linenum;
 471         asize = 2 * _POSIX2_LINE_MAX + 1;
 472         if ((text = malloc(asize)) == NULL)
 473                 err(1, "malloc");
 474         size = 0;
 475         do {
 476                 op = sp = text + size;
 477                 for (; *p; p++) {
 478                         if (*p == '\\' || sawesc) {
 479                                 /*
 480                                  * If this is a continuation from the last
 481                                  * buffer, we won't have a character to
 482                                  * skip over.
 483                                  */
 484                                 if (sawesc)
 485                                         sawesc = 0;
 486                                 else
 487                                         p++;
 488
 489                                 if (*p == '\0') {
 490                                         /*
 491                                          * This escaped character is continued
 492                                          * in the next part of the line.  Note
 493                                          * this fact, then cause the loop to
 494                                          * exit w/ normal EOL case and reenter
 495                                          * above with the new buffer.
 496                                          */
 497                                         sawesc = 1;
 498                                         p--;
 499                                         continue;
 500                                 } else if (strchr("123456789", *p) != NULL) {
 501                                         *sp++ = '\\';
 502                                         ref = *p - '0';
 503                                         if (s->re != NULL &&
 504                                             ref > s->re->re_nsub)
 505                                                 errx(1, "%lu: %s: \\%c not defined in the RE",
 506                                                                 linenum, fname, *p);
 507                                         if (s->maxbref < ref)
 508                                                 s->maxbref = ref;
 509                                 } else if (*p == '&' || *p == '\\')
 510                                         *sp++ = '\\';
 511                         } else if (*p == c) {
 512                                 if (*++p == '\0' && more) {
 513                                         if (cu_fgets(lbuf, sizeof(lbuf), &more))
 514                                                 p = lbuf;
 515                                 }
 516                                 *sp++ = '\0';
 517                                 size += sp - op;
 518                                 if ((s->new = realloc(text, size)) == NULL)
 519                                         err(1, "realloc");
 520                                 return (p);
 521                         } else if (*p == '\n') {
 522                                 errx(1,
 523 "%lu: %s: unescaped newline inside substitute pattern", linenum, fname);
 524                                 /* NOTREACHED */
 525                         }
 526                         *sp++ = *p;
 527                 }
 528                 size += sp - op;
 529                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 530                         asize *= 2;
 531                         if ((text = realloc(text, asize)) == NULL)
 532                                 err(1, "realloc");
 533                 }
 534         } while (cu_fgets(p = lbuf, sizeof(lbuf), &more));
 535         errx(1, "%lu: %s: unterminated substitute in regular expression",
 536                         linenum, fname);
 537         /* NOTREACHED */
 538 }
 539
 540 /*
 541  * Compile the flags of the s command
 542  */
 543 static char *
 544 compile_flags(char *p, struct s_subst *s)
 545 {
 546         int gn;                 /* True if we have seen g or n */
 547         unsigned long nval;
 548         char wfile[_POSIX2_LINE_MAX + 1], *q;
 549
 550         s->n = 1;                               /* Default */
 551         s->p = 0;
 552         s->wfile = NULL;
 553         s->wfd = -1;
 554         s->icase = 0;
 555         for (gn = 0;;) {
 556                 EATSPACE();                     /* EXTENSION */
 557                 switch (*p) {
 558                 case 'g':
 559                         if (gn)
 560                                 errx(1,
 561 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 562                         gn = 1;
 563                         s->n = 0;
 564                         break;
 565                 case '\0':
 566                 case '\n':
 567                 case ';':
 568                         return (p);
 569                 case 'p':
 570                         s->p = 1;
 571                         break;
 572                 case 'I':
 573                         s->icase = 1;
 574                         break;
 575                 case '1': case '2': case '3':
 576                 case '4': case '5': case '6':
 577                 case '7': case '8': case '9':
 578                         if (gn)
 579                                 errx(1,
 580 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 581                         gn = 1;
 582                         errno = 0;
 583                         nval = strtol(p, &p, 10);
 584                         if (errno == ERANGE || nval > INT_MAX)
 585                                 errx(1,
 586 "%lu: %s: overflow in the 'N' substitute flag", linenum, fname);
 587                         s->n = nval;
 588                         p--;
 589                         break;
 590                 case 'w':
 591                         p++;
 592 #ifdef HISTORIC_PRACTICE
 593                         if (*p != ' ') {
 594                                 warnx("%lu: %s: space missing before w wfile", linenum, fname);
 595                                 return (p);
 596                         }
 597 #endif
 598                         EATSPACE();
 599                         q = wfile;
 600                         while (*p) {
 601                                 if (*p == '\n')
 602                                         break;
 603                                 *q++ = *p++;
 604                         }
 605                         *q = '\0';
 606                         if (q == wfile)
 607                                 errx(1, "%lu: %s: no wfile specified", linenum, fname);
 608                         s->wfile = strdup(wfile);
 609                         if (!aflag && (s->wfd = open(wfile,
 610                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 611                             DEFFILEMODE)) == -1)
 612                                 err(1, "%s", wfile);
 613                         return (p);
 614                 default:
 615                         errx(1, "%lu: %s: bad flag in substitute command: '%c'",
 616                                         linenum, fname, *p);
 617                         break;
 618                 }
 619                 p++;
 620         }
 621 }
 622
 623 /*
 624  * Compile a translation set of strings into a lookup table.
 625  */
 626 static char *
 627 compile_tr(char *p, struct s_tr **py)
 628 {
 629         struct s_tr *y;
 630         int i;
 631         const char *op, *np;
 632         char old[_POSIX2_LINE_MAX + 1];
 633         char new[_POSIX2_LINE_MAX + 1];
 634         size_t oclen, oldlen, nclen, newlen;
 635         mbstate_t mbs1, mbs2;
 636
 637         if ((*py = y = malloc(sizeof(*y))) == NULL)
 638                 err(1, NULL);
 639         y->multis = NULL;
 640         y->nmultis = 0;
 641
 642         if (*p == '\0' || *p == '\\')
 643                 errx(1,
 644         "%lu: %s: transform pattern can not be delimited by newline or backslash",
 645                         linenum, fname);
 646         p = compile_delimited(p, old);
 647         if (p == NULL)
 648                 errx(1, "%lu: %s: unterminated transform source string",
 649                                 linenum, fname);
 650         p = compile_delimited(p - 1, new);
 651         if (p == NULL)
 652                 errx(1, "%lu: %s: unterminated transform target string",
 653                                 linenum, fname);
 654         EATSPACE();
 655         op = old;
 656         oldlen = mbsrtowcs(NULL, &op, 0, NULL);
 657         if (oldlen == (size_t)-1)
 658                 err(1, NULL);
 659         np = new;
 660         newlen = mbsrtowcs(NULL, &np, 0, NULL);
 661         if (newlen == (size_t)-1)
 662                 err(1, NULL);
 663         if (newlen != oldlen)
 664                 errx(1, "%lu: %s: transform strings are not the same length",
 665                                 linenum, fname);
 666         if (MB_CUR_MAX == 1) {
 667                 /*
 668                  * The single-byte encoding case is easy: generate a
 669                  * lookup table.
 670                  */
 671                 for (i = 0; i <= UCHAR_MAX; i++)
 672                         y->bytetab[i] = (char)i;
 673                 for (; *op; op++, np++)
 674                         y->bytetab[(u_char)*op] = *np;
 675         } else {
 676                 /*
 677                  * Multi-byte encoding case: generate a lookup table as
 678                  * above, but only for single-byte characters. The first
 679                  * bytes of multi-byte characters have their lookup table
 680                  * entries set to 0, which causes do_tr() to search through
 681                  * an auxiliary vector of multi-byte mappings.
 682                  */
 683                 memset(&mbs1, 0, sizeof(mbs1));
 684                 memset(&mbs2, 0, sizeof(mbs2));
 685                 for (i = 0; i <= UCHAR_MAX; i++)
 686                         y->bytetab[i] = (btowc(i) != WEOF) ? i : 0;
 687                 while (*op != '\0') {
 688                         oclen = mbrlen(op, MB_LEN_MAX, &mbs1);
 689                         if (oclen == (size_t)-1 || oclen == (size_t)-2)
 690                                 errc(1, EILSEQ, NULL);
 691                         nclen = mbrlen(np, MB_LEN_MAX, &mbs2);
 692                         if (nclen == (size_t)-1 || nclen == (size_t)-2)
 693                                 errc(1, EILSEQ, NULL);
 694                         if (oclen == 1 && nclen == 1)
 695                                 y->bytetab[(u_char)*op] = *np;
 696                         else {
 697                                 y->bytetab[(u_char)*op] = 0;
 698                                 y->multis = realloc(y->multis,
 699                                     (y->nmultis + 1) * sizeof(*y->multis));
 700                                 if (y->multis == NULL)
 701                                         err(1, NULL);
 702                                 i = y->nmultis++;
 703                                 y->multis[i].fromlen = oclen;
 704                                 memcpy(y->multis[i].from, op, oclen);
 705                                 y->multis[i].tolen = nclen;
 706                                 memcpy(y->multis[i].to, np, nclen);
 707                         }
 708                         op += oclen;
 709                         np += nclen;
 710                 }
 711         }
 712         return (p);
 713 }
 714
 715 /*
 716  * Compile the text following an a or i command.
 717  */
 718 static char *
 719 compile_text(void)
 720 {
 721         int asize, esc_nl, size;
 722         char *text, *p, *op, *s;
 723         char lbuf[_POSIX2_LINE_MAX + 1];
 724
 725         asize = 2 * _POSIX2_LINE_MAX + 1;
 726         if ((text = malloc(asize)) == NULL)
 727                 err(1, "malloc");
 728         size = 0;
 729         while (cu_fgets(lbuf, sizeof(lbuf), NULL)) {
 730                 op = s = text + size;
 731                 p = lbuf;
 732                 EATSPACE();
 733                 for (esc_nl = 0; *p != '\0'; p++) {
 734                         if (*p == '\\' && p[1] != '\0' && *++p == '\n')
 735                                 esc_nl = 1;
 736                         *s++ = *p;
 737                 }
 738                 size += s - op;
 739                 if (!esc_nl) {
 740                         *s = '\0';
 741                         break;
 742                 }
 743                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 744                         asize *= 2;
 745                         if ((text = realloc(text, asize)) == NULL)
 746                                 err(1, "realloc");
 747                 }
 748         }
 749         text[size] = '\0';
 750         if ((p = realloc(text, size + 1)) == NULL)
 751                 err(1, "realloc");
 752         return (p);
 753 }
 754
 755 /*
 756  * Get an address and return a pointer to the first character after
 757  * it.  Fill the structure pointed to according to the address.
 758  */
 759 static char *
 760 compile_addr(char *p, struct s_addr *a)
 761 {
 762         char *end, re[_POSIX2_LINE_MAX + 1];
 763         int icase;
 764
 765         icase = 0;
 766
 767         switch (*p) {
 768         case '\\':                              /* Context address */
 769                 ++p;
 770                 /* FALLTHROUGH */
 771         case '/':                               /* Context address */
 772                 p = compile_delimited(p, re);
 773                 if (p == NULL)
 774                         errx(1, "%lu: %s: unterminated regular expression", linenum, fname);
 775                 /* Check for case insensitive regexp flag */
 776                 if (*p == 'I') {
 777                         icase = 1;
 778                         p++;
 779                 }
 780                 if (*re == '\0')
 781                         a->u.r = NULL;
 782                 else
 783                         a->u.r = compile_re(re, icase);
 784                 a->type = AT_RE;
 785                 return (p);
 786
 787         case '$':                               /* Last line */
 788                 a->type = AT_LAST;
 789                 return (p + 1);
 790                                                 /* Line number */
 791         case '0': case '1': case '2': case '3': case '4':
 792         case '5': case '6': case '7': case '8': case '9':
 793                 a->type = AT_LINE;
 794                 a->u.l = strtol(p, &end, 10);
 795                 return (end);
 796         default:
 797                 errx(1, "%lu: %s: expected context address", linenum, fname);
 798                 return (NULL);
 799         }
 800 }
 801
 802 /*
 803  * duptoeol --
 804  *      Return a copy of all the characters up to \n or \0.
 805  */
 806 static char *
 807 duptoeol(char *s, const char *ctype)
 808 {
 809         size_t len;
 810         int ws;
 811         char *p, *start;
 812
 813         ws = 0;
 814         for (start = s; *s != '\0' && *s != '\n'; ++s)
 815                 ws = isspace((unsigned char)*s);
 816         *s = '\0';
 817         if (ws)
 818                 warnx("%lu: %s: whitespace after %s", linenum, fname, ctype);
 819         len = s - start + 1;
 820         if ((p = malloc(len)) == NULL)
 821                 err(1, "malloc");
 822         return (memmove(p, start, len));
 823 }
 824
 825 /*
 826  * Convert goto label names to addresses, and count a and r commands, in
 827  * the given subset of the script.  Free the memory used by labels in b
 828  * and t commands (but not by :).
 829  *
 830  * TODO: Remove } nodes
 831  */
 832 static void
 833 fixuplabel(struct s_command *cp, struct s_command *end)
 834 {
 835
 836         for (; cp != end; cp = cp->next)
 837                 switch (cp->code) {
 838                 case 'a':
 839                 case 'r':
 840                         appendnum++;
 841                         break;
 842                 case 'b':
 843                 case 't':
 844                         /* Resolve branch target. */
 845                         if (cp->t == NULL) {
 846                                 cp->u.c = NULL;
 847                                 break;
 848                         }
 849                         if ((cp->u.c = findlabel(cp->t)) == NULL)
 850                                 errx(1, "%lu: %s: undefined label '%s'", linenum, fname, cp->t);
 851                         free(cp->t);
 852                         break;
 853                 case '{':
 854                         /* Do interior commands. */
 855                         fixuplabel(cp->u.c, cp->next);
 856                         break;
 857                 }
 858 }
 859
 860 /*
 861  * Associate the given command label for later lookup.
 862  */
 863 static void
 864 enterlabel(struct s_command *cp)
 865 {
 866         struct labhash **lhp, *lh;
 867         u_char *p;
 868         u_int h, c;
 869
 870         for (h = 0, p = (u_char *)cp->t; (c = *p) != 0; p++)
 871                 h = (h << 5) + h + c;
 872         lhp = &labels[h & LHMASK];
 873         for (lh = *lhp; lh != NULL; lh = lh->lh_next)
 874                 if (lh->lh_hash == h && strcmp(cp->t, lh->lh_cmd->t) == 0)
 875                         errx(1, "%lu: %s: duplicate label '%s'", linenum, fname, cp->t);
 876         if ((lh = malloc(sizeof *lh)) == NULL)
 877                 err(1, "malloc");
 878         lh->lh_next = *lhp;
 879         lh->lh_hash = h;
 880         lh->lh_cmd = cp;
 881         lh->lh_ref = 0;
 882         *lhp = lh;
 883 }
 884
 885 /*
 886  * Find the label contained in the command l in the command linked
 887  * list cp.  L is excluded from the search.  Return NULL if not found.
 888  */
 889 static struct s_command *
 890 findlabel(char *name)
 891 {
 892         struct labhash *lh;
 893         u_char *p;
 894         u_int h, c;
 895
 896         for (h = 0, p = (u_char *)name; (c = *p) != 0; p++)
 897                 h = (h << 5) + h + c;
 898         for (lh = labels[h & LHMASK]; lh != NULL; lh = lh->lh_next) {
 899                 if (lh->lh_hash == h && strcmp(name, lh->lh_cmd->t) == 0) {
 900                         lh->lh_ref = 1;
 901                         return (lh->lh_cmd);
 902                 }
 903         }
 904         return (NULL);
 905 }
 906
 907 /*
 908  * Warn about any unused labels.  As a side effect, release the label hash
 909  * table space.
 910  */
 911 static void
 912 uselabel(void)
 913 {
 914         struct labhash *lh, *next;
 915         int i;
 916
 917         for (i = 0; i < LHSZ; i++) {
 918                 for (lh = labels[i]; lh != NULL; lh = next) {
 919                         next = lh->lh_next;
 920                         if (!lh->lh_ref)
 921                                 warnx("%lu: %s: unused label '%s'",
 922                                     linenum, fname, lh->lh_cmd->t);
 923                         free(lh);
 924                 }
 925         }
 926 }