usr.bin/sed/compile.c

   1 /*      $NetBSD: compile.c,v 1.46 2015/03/12 12:40:41 christos Exp $    */
   2
   3 /*-
   4  * Copyright (c) 1992 Diomidis Spinellis.
   5  * Copyright (c) 1992, 1993
   6  *      The Regents of the University of California.  All rights reserved.
   7  *
   8  * This code is derived from software contributed to Berkeley by
   9  * Diomidis Spinellis of Imperial College, University of London.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #if HAVE_NBTOOL_CONFIG_H
  37 #include "nbtool_config.h"
  38 #endif
  39
  40 #include <sys/cdefs.h>
  41 __RCSID("$NetBSD: compile.c,v 1.46 2015/03/12 12:40:41 christos Exp $");
  42 #ifdef __FBSDID
  43 __FBSDID("$FreeBSD: head/usr.bin/sed/compile.c 259132 2013-12-09 18:57:20Z eadler $");
  44 #endif
  45
  46 #if 0
  47 static const char sccsid[] = "@(#)compile.c     8.1 (Berkeley) 6/6/93";
  48 #endif
  49
  50 #include <sys/types.h>
  51 #include <sys/stat.h>
  52
  53 #include <ctype.h>
  54 #include <err.h>
  55 #include <errno.h>
  56 #include <fcntl.h>
  57 #include <limits.h>
  58 #include <regex.h>
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <string.h>
  62 #include <wchar.h>
  63
  64 #include "defs.h"
  65 #include "extern.h"
  66
  67 #define LHSZ    128
  68 #define LHMASK  (LHSZ - 1)
  69 static struct labhash {
  70         struct  labhash *lh_next;
  71         u_int   lh_hash;
  72         struct  s_command *lh_cmd;
  73         int     lh_ref;
  74 } *labels[LHSZ];
  75
  76 static char      *compile_addr(char *, struct s_addr *);
  77 static char      *compile_ccl(char **, char *);
  78 static char      *compile_delimited(char *, char *, int);
  79 static char      *compile_flags(char *, struct s_subst *);
  80 static regex_t   *compile_re(char *, int);
  81 static char      *compile_subst(char *, struct s_subst *);
  82 static char      *compile_text(void);
  83 static char      *compile_tr(char *, struct s_tr **);
  84 static struct s_command
  85                 **compile_stream(struct s_command **);
  86 static char      *duptoeol(char *, const char *);
  87 static void       enterlabel(struct s_command *);
  88 static struct s_command
  89                  *findlabel(char *);
  90 static void       fixuplabel(struct s_command *, struct s_command *);
  91 static void       uselabel(void);
  92
  93 /*
  94  * Command specification.  This is used to drive the command parser.
  95  */
  96 struct s_format {
  97         char code;                              /* Command code */
  98         int naddr;                              /* Number of address args */
  99         enum e_args args;                       /* Argument type */
 100 };
 101
 102 static struct s_format cmd_fmts[] = {
 103         {'{', 2, GROUP},
 104         {'}', 0, ENDGROUP},
 105         {'a', 1, TEXT},
 106         {'b', 2, BRANCH},
 107         {'c', 2, TEXT},
 108         {'d', 2, EMPTY},
 109         {'D', 2, EMPTY},
 110         {'g', 2, EMPTY},
 111         {'G', 2, EMPTY},
 112         {'h', 2, EMPTY},
 113         {'H', 2, EMPTY},
 114         {'i', 1, TEXT},
 115         {'l', 2, EMPTY},
 116         {'n', 2, EMPTY},
 117         {'N', 2, EMPTY},
 118         {'p', 2, EMPTY},
 119         {'P', 2, EMPTY},
 120         {'q', 1, EMPTY},
 121         {'r', 1, RFILE},
 122         {'s', 2, SUBST},
 123         {'t', 2, BRANCH},
 124         {'w', 2, WFILE},
 125         {'x', 2, EMPTY},
 126         {'y', 2, TR},
 127         {'!', 2, NONSEL},
 128         {':', 0, LABEL},
 129         {'#', 0, COMMENT},
 130         {'=', 1, EMPTY},
 131         {'\0', 0, COMMENT},
 132 };
 133
 134 /* The compiled program. */
 135 struct s_command *prog;
 136
 137 /*
 138  * Compile the program into prog.
 139  * Initialise appends.
 140  */
 141 void
 142 compile(void)
 143 {
 144         *compile_stream(&prog) = NULL;
 145         fixuplabel(prog, NULL);
 146         uselabel();
 147         if (appendnum > 0)
 148                 appends = xmalloc(sizeof(struct s_appends) * appendnum);
 149         match = xmalloc((maxnsub + 1) * sizeof(regmatch_t));
 150 }
 151
 152 #define EATSPACE() do {                                                 \
 153         if (p)                                                          \
 154                 while (*p && isspace((unsigned char)*p))                \
 155                         p++;                                            \
 156         } while (0)
 157
 158 static struct s_command **
 159 compile_stream(struct s_command **link)
 160 {
 161         char *p;
 162         static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */
 163         struct s_command *cmd, *cmd2, *stack;
 164         struct s_format *fp;
 165         char re[_POSIX2_LINE_MAX + 1];
 166         int naddr;                              /* Number of addresses */
 167
 168         stack = 0;
 169         for (;;) {
 170                 if ((p = cu_fgets(lbuf, sizeof(lbuf), NULL)) == NULL) {
 171                         if (stack != 0)
 172                                 errx(1, "%lu: %s: unexpected EOF (pending }'s)",
 173                                                         linenum, fname);
 174                         return (link);
 175                 }
 176
 177 semicolon:      EATSPACE();
 178                 if (p) {
 179                         if (*p == '#' || *p == '\0')
 180                                 continue;
 181                         else if (*p == ';') {
 182                                 p++;
 183                                 goto semicolon;
 184                         }
 185                 }
 186                 *link = cmd = xmalloc(sizeof(struct s_command));
 187                 link = &cmd->next;
 188                 cmd->startline = cmd->nonsel = 0;
 189                 /* First parse the addresses */
 190                 naddr = 0;
 191
 192 /* Valid characters to start an address */
 193 #define addrchar(c)     (strchr("0123456789/\\$", (c)))
 194                 if (addrchar(*p)) {
 195                         naddr++;
 196                         cmd->a1 = xmalloc(sizeof(struct s_addr));
 197                         p = compile_addr(p, cmd->a1);
 198                         EATSPACE();                             /* EXTENSION */
 199                         if (*p == ',') {
 200                                 p++;
 201                                 EATSPACE();                     /* EXTENSION */
 202                                 naddr++;
 203                                 cmd->a2 = xmalloc(sizeof(struct s_addr));
 204                                 p = compile_addr(p, cmd->a2);
 205                                 EATSPACE();
 206                         } else
 207                                 cmd->a2 = 0;
 208                 } else
 209                         cmd->a1 = cmd->a2 = 0;
 210
 211 nonsel:         /* Now parse the command */
 212                 if (!*p)
 213                         errx(1, "%lu: %s: command expected", linenum, fname);
 214                 cmd->code = *p;
 215                 for (fp = cmd_fmts; fp->code; fp++)
 216                         if (fp->code == *p)
 217                                 break;
 218                 if (!fp->code)
 219                         errx(1, "%lu: %s: invalid command code %c", linenum, fname, *p);
 220                 if (naddr > fp->naddr)
 221                         errx(1,
 222                                 "%lu: %s: command %c expects up to %d address(es), found %d",
 223                                 linenum, fname, *p, fp->naddr, naddr);
 224                 switch (fp->args) {
 225                 case NONSEL:                    /* ! */
 226                         p++;
 227                         EATSPACE();
 228                         cmd->nonsel = ! cmd->nonsel;
 229                         goto nonsel;
 230                 case GROUP:                     /* { */
 231                         p++;
 232                         EATSPACE();
 233                         cmd->next = stack;
 234                         stack = cmd;
 235                         link = &cmd->u.c;
 236                         if (*p)
 237                                 goto semicolon;
 238                         break;
 239                 case ENDGROUP:
 240                         /*
 241                          * Short-circuit command processing, since end of
 242                          * group is really just a noop.
 243                          */
 244                         cmd->nonsel = 1;
 245                         if (stack == 0)
 246                                 errx(1, "%lu: %s: unexpected }", linenum, fname);
 247                         cmd2 = stack;
 248                         stack = cmd2->next;
 249                         cmd2->next = cmd;
 250                         /*FALLTHROUGH*/
 251                 case EMPTY:             /* d D g G h H l n N p P q x = \0 */
 252                         p++;
 253                         EATSPACE();
 254                         switch (*p) {
 255                         case ';':
 256                                 p++;
 257                                 link = &cmd->next;
 258                                 goto semicolon;
 259                         case '}':
 260                                 goto semicolon;
 261                         case '\0':
 262                                 break;
 263                         default:
 264                                 errx(1, "%lu: %s: extra characters at the end of %c command",
 265                                                 linenum, fname, cmd->code);
 266                         }
 267                         break;
 268                 case TEXT:                      /* a c i */
 269                         p++;
 270                         EATSPACE();
 271                         if (*p != '\\')
 272                                 errx(1,
 273 "%lu: %s: command %c expects \\ followed by text", linenum, fname, cmd->code);
 274                         p++;
 275                         EATSPACE();
 276                         if (*p)
 277                                 errx(1,
 278                                 "%lu: %s: extra characters after \\ at the end of %c command",
 279                                 linenum, fname, cmd->code);
 280                         cmd->t = compile_text();
 281                         break;
 282                 case COMMENT:                   /* \0 # */
 283                         break;
 284                 case WFILE:                     /* w */
 285                         p++;
 286                         EATSPACE();
 287                         if (*p == '\0')
 288                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 289                         cmd->t = duptoeol(p, "w command");
 290                         if (aflag)
 291                                 cmd->u.fd = -1;
 292                         else if ((cmd->u.fd = open(p,
 293                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 294                             DEFFILEMODE)) == -1)
 295                                 err(1, "%s", p);
 296                         break;
 297                 case RFILE:                     /* r */
 298                         p++;
 299                         EATSPACE();
 300                         if (*p == '\0')
 301                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 302                         else
 303                                 cmd->t = duptoeol(p, "read command");
 304                         break;
 305                 case BRANCH:                    /* b t */
 306                         p++;
 307                         EATSPACE();
 308                         if (*p == '\0')
 309                                 cmd->t = NULL;
 310                         else
 311                                 cmd->t = duptoeol(p, "branch");
 312                         break;
 313                 case LABEL:                     /* : */
 314                         p++;
 315                         EATSPACE();
 316                         cmd->t = duptoeol(p, "label");
 317                         if (strlen(p) == 0)
 318                                 errx(1, "%lu: %s: empty label", linenum, fname);
 319                         enterlabel(cmd);
 320                         break;
 321                 case SUBST:                     /* s */
 322                         p++;
 323                         if (*p == '\0' || *p == '\\')
 324                                 errx(1,
 325 "%lu: %s: substitute pattern can not be delimited by newline or backslash",
 326                                         linenum, fname);
 327                         cmd->u.s = xcalloc(1, sizeof(struct s_subst));
 328                         p = compile_delimited(p, re, 0);
 329                         if (p == NULL)
 330                                 errx(1,
 331                                 "%lu: %s: unterminated substitute pattern", linenum, fname);
 332
 333                         /* Compile RE with no case sensitivity temporarily */
 334                         if (*re == '\0')
 335                                 cmd->u.s->re = NULL;
 336                         else
 337                                 cmd->u.s->re = compile_re(re, 0);
 338                         --p;
 339                         p = compile_subst(p, cmd->u.s);
 340                         p = compile_flags(p, cmd->u.s);
 341
 342                         /* Recompile RE with case sensitivity from "I" flag if any */
 343                         if (*re == '\0')
 344                                 cmd->u.s->re = NULL;
 345                         else
 346                                 cmd->u.s->re = compile_re(re, cmd->u.s->icase);
 347                         EATSPACE();
 348                         if (*p == ';') {
 349                                 p++;
 350                                 link = &cmd->next;
 351                                 goto semicolon;
 352                         }
 353                         break;
 354                 case TR:                        /* y */
 355                         p++;
 356                         p = compile_tr(p, &cmd->u.y);
 357                         EATSPACE();
 358                         switch (*p) {
 359                         case ';':
 360                                 p++;
 361                                 link = &cmd->next;
 362                                 goto semicolon;
 363                         case '}':
 364                                 goto semicolon;
 365                         case '\0':
 366                                 break;
 367                         default:
 368                                 errx(1,
 369 "%lu: %s: extra text at the end of a transform command", linenum, fname);
 370                         }
 371                         if (*p)
 372                         break;
 373                 }
 374         }
 375 }
 376
 377 /*
 378  * Get a delimited string.  P points to the delimeter of the string; d points
 379  * to a buffer area.  Newline and delimiter escapes are processed; other
 380  * escapes are ignored.
 381  *
 382  * Returns a pointer to the first character after the final delimiter or NULL
 383  * in the case of a non-terminated string.  The character array d is filled
 384  * with the processed string.
 385  */
 386 static char *
 387 compile_delimited(char *p, char *d, int is_tr)
 388 {
 389         char c;
 390
 391         c = *p++;
 392         if (c == '\0')
 393                 return (NULL);
 394         else if (c == '\\')
 395                 errx(1, "%lu: %s: \\ can not be used as a string delimiter",
 396                                 linenum, fname);
 397         else if (c == '\n')
 398                 errx(1, "%lu: %s: newline can not be used as a string delimiter",
 399                                 linenum, fname);
 400         while (*p) {
 401                 if (*p == '[' && *p != c) {
 402                         if ((d = compile_ccl(&p, d)) == NULL)
 403                                 errx(1, "%lu: %s: unbalanced brackets ([])", linenum, fname);
 404                         continue;
 405                 } else if (*p == '\\' && p[1] == '[') {
 406                         *d++ = *p++;
 407                 } else if (*p == '\\' && p[1] == c)
 408                         p++;
 409                 else if (*p == '\\' && p[1] == 'n') {
 410                         *d++ = '\n';
 411                         p += 2;
 412                         continue;
 413                 } else if (*p == '\\' && p[1] == '\\') {
 414                         if (is_tr)
 415                                 p++;
 416                         else
 417                                 *d++ = *p++;
 418                 } else if (*p == c) {
 419                         *d = '\0';
 420                         return (p + 1);
 421                 }
 422                 *d++ = *p++;
 423         }
 424         return (NULL);
 425 }
 426
 427
 428 /* compile_ccl: expand a POSIX character class */
 429 static char *
 430 compile_ccl(char **sp, char *t)
 431 {
 432         int c, d;
 433         char *s = *sp;
 434
 435         *t++ = *s++;
 436         if (*s == '^')
 437                 *t++ = *s++;
 438         if (*s == ']')
 439                 *t++ = *s++;
 440         for (; *s && (*t = *s) != ']'; s++, t++)
 441                 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) {
 442                         *++t = *++s, t++, s++;
 443                         for (c = *s; (*t = *s) != ']' || c != d; s++, t++)
 444                                 if ((c = *s) == '\0')
 445                                         return NULL;
 446                 }
 447         return (*s == ']') ? *sp = ++s, ++t : NULL;
 448 }
 449
 450 /*
 451  * Compiles the regular expression in RE and returns a pointer to the compiled
 452  * regular expression.
 453  * Cflags are passed to regcomp.
 454  */
 455 static regex_t *
 456 compile_re(char *re, int case_insensitive)
 457 {
 458         regex_t *rep;
 459         int eval, flags;
 460
 461
 462         flags = rflags;
 463         if (case_insensitive)
 464                 flags |= REG_ICASE;
 465         rep = xmalloc(sizeof(regex_t));
 466         if ((eval = regcomp(rep, re, flags)) != 0)
 467                 errx(1, "%lu: %s: RE error: %s",
 468                                 linenum, fname, strregerror(eval, rep));
 469         if (maxnsub < rep->re_nsub)
 470                 maxnsub = rep->re_nsub;
 471         return (rep);
 472 }
 473
 474 /*
 475  * Compile the substitution string of a regular expression and set res to
 476  * point to a saved copy of it.  Nsub is the number of parenthesized regular
 477  * expressions.
 478  */
 479 static char *
 480 compile_subst(char *p, struct s_subst *s)
 481 {
 482         static char lbuf[_POSIX2_LINE_MAX + 1];
 483         size_t asize, size;
 484         u_char ref;
 485         char c, *text, *op, *sp;
 486         int more = 1, sawesc = 0;
 487
 488         c = *p++;                       /* Terminator character */
 489         if (c == '\0')
 490                 return (NULL);
 491
 492         s->maxbref = 0;
 493         s->linenum = linenum;
 494         asize = 2 * _POSIX2_LINE_MAX + 1;
 495         text = xmalloc(asize);
 496         size = 0;
 497         do {
 498                 op = sp = text + size;
 499                 for (; *p; p++) {
 500                         if (*p == '\\' || sawesc) {
 501                                 /*
 502                                  * If this is a continuation from the last
 503                                  * buffer, we won't have a character to
 504                                  * skip over.
 505                                  */
 506                                 if (sawesc)
 507                                         sawesc = 0;
 508                                 else
 509                                         p++;
 510
 511                                 if (*p == '\0') {
 512                                         /*
 513                                          * This escaped character is continued
 514                                          * in the next part of the line.  Note
 515                                          * this fact, then cause the loop to
 516                                          * exit w/ normal EOL case and reenter
 517                                          * above with the new buffer.
 518                                          */
 519                                         sawesc = 1;
 520                                         p--;
 521                                         continue;
 522                                 } else if (strchr("123456789", *p) != NULL) {
 523                                         *sp++ = '\\';
 524                                         ref = (u_char)(*p - '0');
 525                                         if (s->re != NULL &&
 526                                             ref > s->re->re_nsub)
 527                                                 errx(1, "%lu: %s: \\%c not defined in the RE",
 528                                                                 linenum, fname, *p);
 529                                         if (s->maxbref < ref)
 530                                                 s->maxbref = ref;
 531                                 } else if (*p == '&' || *p == '\\')
 532                                         *sp++ = '\\';
 533                         } else if (*p == c) {
 534                                 if (*++p == '\0' && more) {
 535                                         if (cu_fgets(lbuf, sizeof(lbuf), &more))
 536                                                 p = lbuf;
 537                                 }
 538                                 *sp++ = '\0';
 539                                 size += (size_t)(sp - op);
 540                                 s->new = xrealloc(text, size);
 541                                 return (p);
 542                         } else if (*p == '\n') {
 543                                 errx(1,
 544 "%lu: %s: unescaped newline inside substitute pattern", linenum, fname);
 545                                 /* NOTREACHED */
 546                         }
 547                         *sp++ = *p;
 548                 }
 549                 size += (size_t)(sp - op);
 550                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 551                         asize *= 2;
 552                         text = xrealloc(text, asize);
 553                 }
 554         } while (cu_fgets(p = lbuf, sizeof(lbuf), &more));
 555         errx(1, "%lu: %s: unterminated substitute in regular expression",
 556                         linenum, fname);
 557         /* NOTREACHED */
 558 }
 559
 560 /*
 561  * Compile the flags of the s command
 562  */
 563 static char *
 564 compile_flags(char *p, struct s_subst *s)
 565 {
 566         int gn;                 /* True if we have seen g or n */
 567         unsigned long nval;
 568         char wfile[_POSIX2_LINE_MAX + 1], *q;
 569
 570         s->n = 1;                               /* Default */
 571         s->p = 0;
 572         s->wfile = NULL;
 573         s->wfd = -1;
 574         s->icase = 0;
 575         for (gn = 0;;) {
 576                 EATSPACE();                     /* EXTENSION */
 577                 switch (*p) {
 578                 case 'g':
 579                         if (gn)
 580                                 errx(1,
 581 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 582                         gn = 1;
 583                         s->n = 0;
 584                         break;
 585                 case '\0':
 586                 case '\n':
 587                 case ';':
 588                         return (p);
 589                 case 'p':
 590                         s->p = 1;
 591                         break;
 592                 case 'i':
 593                 case 'I':
 594                         s->icase = 1;
 595                         break;
 596                 case '1': case '2': case '3':
 597                 case '4': case '5': case '6':
 598                 case '7': case '8': case '9':
 599                         if (gn)
 600                                 errx(1,
 601 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 602                         gn = 1;
 603                         errno = 0;
 604                         nval = strtoul(p, &p, 10);
 605                         if (errno == ERANGE || nval > INT_MAX)
 606                                 errx(1,
 607 "%lu: %s: overflow in the 'N' substitute flag", linenum, fname);
 608                         s->n = (int)nval;
 609                         p--;
 610                         break;
 611                 case 'w':
 612                         p++;
 613 #ifdef HISTORIC_PRACTICE
 614                         if (*p != ' ') {
 615                                 warnx("%lu: %s: space missing before w wfile", linenum, fname);
 616                                 return (p);
 617                         }
 618 #endif
 619                         EATSPACE();
 620                         q = wfile;
 621                         while (*p) {
 622                                 if (*p == '\n')
 623                                         break;
 624                                 *q++ = *p++;
 625                         }
 626                         *q = '\0';
 627                         if (q == wfile)
 628                                 errx(1, "%lu: %s: no wfile specified", linenum, fname);
 629                         s->wfile = strdup(wfile);
 630                         if (!aflag && (s->wfd = open(wfile,
 631                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 632                             DEFFILEMODE)) == -1)
 633                                 err(1, "%s", wfile);
 634                         return (p);
 635                 default:
 636                         errx(1, "%lu: %s: bad flag in substitute command: '%c'",
 637                                         linenum, fname, *p);
 638                         break;
 639                 }
 640                 p++;
 641         }
 642 }
 643
 644 /*
 645  * Compile a translation set of strings into a lookup table.
 646  */
 647 static char *
 648 compile_tr(char *p, struct s_tr **py)
 649 {
 650         struct s_tr *y;
 651         size_t i;
 652         const char *op, *np;
 653         char old[_POSIX2_LINE_MAX + 1];
 654         char new[_POSIX2_LINE_MAX + 1];
 655         size_t oclen, oldlen, nclen, newlen;
 656         mbstate_t mbs1, mbs2;
 657
 658         *py = y = xmalloc(sizeof(*y));
 659         y->multis = NULL;
 660         y->nmultis = 0;
 661
 662         if (*p == '\0' || *p == '\\')
 663                 errx(1,
 664         "%lu: %s: transform pattern can not be delimited by newline or backslash",
 665                         linenum, fname);
 666         p = compile_delimited(p, old, 1);
 667         if (p == NULL)
 668                 errx(1, "%lu: %s: unterminated transform source string",
 669                                 linenum, fname);
 670         p = compile_delimited(p - 1, new, 1);
 671         if (p == NULL)
 672                 errx(1, "%lu: %s: unterminated transform target string",
 673                                 linenum, fname);
 674         EATSPACE();
 675         op = old;
 676         oldlen = mbsrtowcs(NULL, &op, 0, NULL);
 677         if (oldlen == (size_t)-1)
 678                 err(1, NULL);
 679         np = new;
 680         newlen = mbsrtowcs(NULL, &np, 0, NULL);
 681         if (newlen == (size_t)-1)
 682                 err(1, NULL);
 683         if (newlen != oldlen)
 684                 errx(1, "%lu: %s: transform strings are not the same length",
 685                                 linenum, fname);
 686         if (MB_CUR_MAX == 1) {
 687                 /*
 688                  * The single-byte encoding case is easy: generate a
 689                  * lookup table.
 690                  */
 691                 for (i = 0; i <= UCHAR_MAX; i++)
 692                         y->bytetab[i] = (u_char)i;
 693                 for (; *op; op++, np++)
 694                         y->bytetab[(u_char)*op] = (u_char)*np;
 695         } else {
 696                 /*
 697                  * Multi-byte encoding case: generate a lookup table as
 698                  * above, but only for single-byte characters. The first
 699                  * bytes of multi-byte characters have their lookup table
 700                  * entries set to 0, which causes do_tr() to search through
 701                  * an auxiliary vector of multi-byte mappings.
 702                  */
 703                 memset(&mbs1, 0, sizeof(mbs1));
 704                 memset(&mbs2, 0, sizeof(mbs2));
 705                 for (i = 0; i <= UCHAR_MAX; i++)
 706                         y->bytetab[i] = (u_char)((btowc((int)i) != WEOF) ? i : 0);
 707                 while (*op != '\0') {
 708                         oclen = mbrlen(op, MB_LEN_MAX, &mbs1);
 709                         if (oclen == (size_t)-1 || oclen == (size_t)-2)
 710                                 errc(1, EILSEQ, NULL);
 711                         nclen = mbrlen(np, MB_LEN_MAX, &mbs2);
 712                         if (nclen == (size_t)-1 || nclen == (size_t)-2)
 713                                 errc(1, EILSEQ, NULL);
 714                         if (oclen == 1 && nclen == 1)
 715                                 y->bytetab[(u_char)*op] = (u_char)*np;
 716                         else {
 717                                 y->bytetab[(u_char)*op] = 0;
 718                                 y->multis = xrealloc(y->multis,
 719                                     (y->nmultis + 1) * sizeof(*y->multis));
 720                                 i = y->nmultis++;
 721                                 y->multis[i].fromlen = oclen;
 722                                 memcpy(y->multis[i].from, op, oclen);
 723                                 y->multis[i].tolen = nclen;
 724                                 memcpy(y->multis[i].to, np, nclen);
 725                         }
 726                         op += oclen;
 727                         np += nclen;
 728                 }
 729         }
 730         return (p);
 731 }
 732
 733 /*
 734  * Compile the text following an a or i command.
 735  */
 736 static char *
 737 compile_text(void)
 738 {
 739         size_t asize, size;
 740         int esc_nl;
 741         char *text, *p, *op, *s;
 742         char lbuf[_POSIX2_LINE_MAX + 1];
 743
 744         asize = 2 * _POSIX2_LINE_MAX + 1;
 745         text = xmalloc(asize);
 746         size = 0;
 747         while (cu_fgets(lbuf, sizeof(lbuf), NULL)) {
 748                 op = s = text + size;
 749                 p = lbuf;
 750                 EATSPACE();
 751                 for (esc_nl = 0; *p != '\0'; p++) {
 752                         if (*p == '\\' && p[1] != '\0' && *++p == '\n')
 753                                 esc_nl = 1;
 754                         *s++ = *p;
 755                 }
 756                 size += (size_t)(s - op);
 757                 if (!esc_nl) {
 758                         *s = '\0';
 759                         break;
 760                 }
 761                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 762                         asize *= 2;
 763                         text = xrealloc(text, asize);
 764                 }
 765         }
 766         text[size] = '\0';
 767         p = xrealloc(text, size + 1);
 768         return (p);
 769 }
 770
 771 /*
 772  * Get an address and return a pointer to the first character after
 773  * it.  Fill the structure pointed to according to the address.
 774  */
 775 static char *
 776 compile_addr(char *p, struct s_addr *a)
 777 {
 778         char *end, re[_POSIX2_LINE_MAX + 1];
 779         int icase;
 780
 781         icase = 0;
 782
 783         a->type = 0;
 784         switch (*p) {
 785         case '\\':                              /* Context address */
 786                 ++p;
 787                 /* FALLTHROUGH */
 788         case '/':                               /* Context address */
 789                 p = compile_delimited(p, re, 0);
 790                 if (p == NULL)
 791                         errx(1, "%lu: %s: unterminated regular expression", linenum, fname);
 792                 /* Check for case insensitive regexp flag */
 793                 if (*p == 'I') {
 794                         icase = 1;
 795                         p++;
 796                 }
 797                 if (*re == '\0')
 798                         a->u.r = NULL;
 799                 else
 800                         a->u.r = compile_re(re, icase);
 801                 a->type = AT_RE;
 802                 return (p);
 803
 804         case '$':                               /* Last line */
 805                 a->type = AT_LAST;
 806                 return (p + 1);
 807
 808         case '+':                               /* Relative line number */
 809                 a->type = AT_RELLINE;
 810                 p++;
 811                 /* FALLTHROUGH */
 812                                                 /* Line number */
 813         case '0': case '1': case '2': case '3': case '4':
 814         case '5': case '6': case '7': case '8': case '9':
 815                 if (a->type == 0)
 816                         a->type = AT_LINE;
 817                 a->u.l = strtoul(p, &end, 10);
 818                 return (end);
 819         default:
 820                 errx(1, "%lu: %s: expected context address", linenum, fname);
 821                 return (NULL);
 822         }
 823 }
 824
 825 /*
 826  * duptoeol --
 827  *      Return a copy of all the characters up to \n or \0.
 828  */
 829 static char *
 830 duptoeol(char *s, const char *ctype)
 831 {
 832         size_t len;
 833         int ws;
 834         char *p, *start;
 835
 836         ws = 0;
 837         for (start = s; *s != '\0' && *s != '\n'; ++s)
 838                 ws = isspace((unsigned char)*s);
 839         *s = '\0';
 840         if (ws)
 841                 warnx("%lu: %s: whitespace after %s", linenum, fname, ctype);
 842         len = (size_t)(s - start + 1);
 843         p = xmalloc(len);
 844         return (memmove(p, start, len));
 845 }
 846
 847 /*
 848  * Convert goto label names to addresses, and count a and r commands, in
 849  * the given subset of the script.  Free the memory used by labels in b
 850  * and t commands (but not by :).
 851  *
 852  * TODO: Remove } nodes
 853  */
 854 static void
 855 fixuplabel(struct s_command *cp, struct s_command *end)
 856 {
 857
 858         for (; cp != end; cp = cp->next)
 859                 switch (cp->code) {
 860                 case 'a':
 861                 case 'r':
 862                         appendnum++;
 863                         break;
 864                 case 'b':
 865                 case 't':
 866                         /* Resolve branch target. */
 867                         if (cp->t == NULL) {
 868                                 cp->u.c = NULL;
 869                                 break;
 870                         }
 871                         if ((cp->u.c = findlabel(cp->t)) == NULL)
 872                                 errx(1, "%lu: %s: undefined label '%s'", linenum, fname, cp->t);
 873                         free(cp->t);
 874                         break;
 875                 case '{':
 876                         /* Do interior commands. */
 877                         fixuplabel(cp->u.c, cp->next);
 878                         break;
 879                 }
 880 }
 881
 882 /*
 883  * Associate the given command label for later lookup.
 884  */
 885 static void
 886 enterlabel(struct s_command *cp)
 887 {
 888         struct labhash **lhp, *lh;
 889         u_char *p;
 890         u_int h, c;
 891
 892         for (h = 0, p = (u_char *)cp->t; (c = *p) != 0; p++)
 893                 h = (h << 5) + h + c;
 894         lhp = &labels[h & LHMASK];
 895         for (lh = *lhp; lh != NULL; lh = lh->lh_next)
 896                 if (lh->lh_hash == h && strcmp(cp->t, lh->lh_cmd->t) == 0)
 897                         errx(1, "%lu: %s: duplicate label '%s'", linenum, fname, cp->t);
 898         lh = xmalloc(sizeof *lh);
 899         lh->lh_next = *lhp;
 900         lh->lh_hash = h;
 901         lh->lh_cmd = cp;
 902         lh->lh_ref = 0;
 903         *lhp = lh;
 904 }
 905
 906 /*
 907  * Find the label contained in the command l in the command linked
 908  * list cp.  L is excluded from the search.  Return NULL if not found.
 909  */
 910 static struct s_command *
 911 findlabel(char *name)
 912 {
 913         struct labhash *lh;
 914         u_char *p;
 915         u_int h, c;
 916
 917         for (h = 0, p = (u_char *)name; (c = *p) != 0; p++)
 918                 h = (h << 5) + h + c;
 919         for (lh = labels[h & LHMASK]; lh != NULL; lh = lh->lh_next) {
 920                 if (lh->lh_hash == h && strcmp(name, lh->lh_cmd->t) == 0) {
 921                         lh->lh_ref = 1;
 922                         return (lh->lh_cmd);
 923                 }
 924         }
 925         return (NULL);
 926 }
 927
 928 /*
 929  * Warn about any unused labels.  As a side effect, release the label hash
 930  * table space.
 931  */
 932 static void
 933 uselabel(void)
 934 {
 935         struct labhash *lh, *next;
 936         int i;
 937
 938         for (i = 0; i < LHSZ; i++) {
 939                 for (lh = labels[i]; lh != NULL; lh = next) {
 940                         next = lh->lh_next;
 941                         if (!lh->lh_ref)
 942                                 warnx("%lu: %s: unused label '%s'",
 943                                     linenum, fname, lh->lh_cmd->t);
 944                         free(lh);
 945                 }
 946         }
 947 }