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