usr.bin/sed/compile.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   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 #include <sys/cdefs.h>
  37 #ifndef lint
  38 static const char sccsid[] = "@(#)compile.c     8.1 (Berkeley) 6/6/93";
  39 #endif
  40
  41 #include <sys/types.h>
  42 #include <sys/stat.h>
  43
  44 #include <ctype.h>
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <limits.h>
  49 #include <regex.h>
  50 #include <stdbool.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #include <wchar.h>
  55
  56 #include "defs.h"
  57 #include "extern.h"
  58
  59 #define LHSZ    128
  60 #define LHMASK  (LHSZ - 1)
  61 static struct labhash {
  62         struct  labhash *lh_next;
  63         u_int   lh_hash;
  64         struct  s_command *lh_cmd;
  65         int     lh_ref;
  66 } *labels[LHSZ];
  67
  68 static char      *compile_addr(char *, struct s_addr *);
  69 static char      *compile_ccl(char **, char *);
  70 static char      *compile_delimited(char *, char *, int);
  71 static char      *compile_flags(char *, struct s_subst *);
  72 static regex_t   *compile_re(char *, int);
  73 static char      *compile_subst(char *, struct s_subst *);
  74 static char      *compile_text(void);
  75 static char      *compile_tr(char *, struct s_tr **);
  76 static struct s_command
  77                 **compile_stream(struct s_command **);
  78 static char      *duptoeol(char *, const char *);
  79 static void       enterlabel(struct s_command *);
  80 static struct s_command
  81                  *findlabel(char *);
  82 static void       fixuplabel(struct s_command *, struct s_command *);
  83 static void       uselabel(void);
  84
  85 /*
  86  * Command specification.  This is used to drive the command parser.
  87  */
  88 struct s_format {
  89         char code;                              /* Command code */
  90         int naddr;                              /* Number of address args */
  91         enum e_args args;                       /* Argument type */
  92 };
  93
  94 static struct s_format cmd_fmts[] = {
  95         {'{', 2, GROUP},
  96         {'}', 0, ENDGROUP},
  97         {'a', 1, TEXT},
  98         {'b', 2, BRANCH},
  99         {'c', 2, TEXT},
 100         {'d', 2, EMPTY},
 101         {'D', 2, EMPTY},
 102         {'g', 2, EMPTY},
 103         {'G', 2, EMPTY},
 104         {'h', 2, EMPTY},
 105         {'H', 2, EMPTY},
 106         {'i', 1, TEXT},
 107         {'l', 2, EMPTY},
 108         {'n', 2, EMPTY},
 109         {'N', 2, EMPTY},
 110         {'p', 2, EMPTY},
 111         {'P', 2, EMPTY},
 112         {'q', 1, EMPTY},
 113         {'r', 1, RFILE},
 114         {'s', 2, SUBST},
 115         {'t', 2, BRANCH},
 116         {'w', 2, WFILE},
 117         {'x', 2, EMPTY},
 118         {'y', 2, TR},
 119         {'!', 2, NONSEL},
 120         {':', 0, LABEL},
 121         {'#', 0, COMMENT},
 122         {'=', 1, EMPTY},
 123         {'\0', 0, COMMENT},
 124 };
 125
 126 /* The compiled program. */
 127 struct s_command *prog;
 128
 129 /*
 130  * Compile the program into prog.
 131  * Initialise appends.
 132  */
 133 void
 134 compile(void)
 135 {
 136         *compile_stream(&prog) = NULL;
 137         fixuplabel(prog, NULL);
 138         uselabel();
 139         if (appendnum == 0)
 140                 appends = NULL;
 141         else if ((appends = malloc(sizeof(struct s_appends) * appendnum)) ==
 142             NULL)
 143                 err(1, "malloc");
 144         if ((match = malloc((maxnsub + 1) * sizeof(regmatch_t))) == NULL)
 145                 err(1, "malloc");
 146 }
 147
 148 #define EATSPACE() do {                                                 \
 149         if (p)                                                          \
 150                 while (*p && isspace((unsigned char)*p))                \
 151                         p++;                                            \
 152         } while (0)
 153
 154 static struct s_command **
 155 compile_stream(struct s_command **link)
 156 {
 157         char *p;
 158         static char lbuf[_POSIX2_LINE_MAX + 1]; /* To save stack */
 159         struct s_command *cmd, *cmd2, *stack;
 160         struct s_format *fp;
 161         char re[_POSIX2_LINE_MAX + 1];
 162         int naddr;                              /* Number of addresses */
 163
 164         stack = NULL;
 165         for (;;) {
 166                 if ((p = cu_fgets(lbuf, sizeof(lbuf), NULL)) == NULL) {
 167                         if (stack != NULL)
 168                                 errx(1, "%lu: %s: unexpected EOF (pending }'s)",
 169                                                         linenum, fname);
 170                         return (link);
 171                 }
 172
 173 semicolon:      EATSPACE();
 174                 if (p) {
 175                         if (*p == '#' || *p == '\0')
 176                                 continue;
 177                         else if (*p == ';') {
 178                                 p++;
 179                                 goto semicolon;
 180                         }
 181                 }
 182                 if ((*link = cmd = malloc(sizeof(struct s_command))) == NULL)
 183                         err(1, "malloc");
 184                 link = &cmd->next;
 185                 cmd->startline = cmd->nonsel = 0;
 186                 /* First parse the addresses */
 187                 naddr = 0;
 188
 189 /* Valid characters to start an address */
 190 #define addrchar(c)     (strchr("0123456789/\\$", (c)))
 191                 if (addrchar(*p)) {
 192                         naddr++;
 193                         if ((cmd->a1 = malloc(sizeof(struct s_addr))) == NULL)
 194                                 err(1, "malloc");
 195                         p = compile_addr(p, cmd->a1);
 196                         EATSPACE();                             /* EXTENSION */
 197                         if (*p == ',') {
 198                                 p++;
 199                                 EATSPACE();                     /* EXTENSION */
 200                                 naddr++;
 201                                 if ((cmd->a2 = malloc(sizeof(struct s_addr)))
 202                                     == NULL)
 203                                         err(1, "malloc");
 204                                 p = compile_addr(p, cmd->a2);
 205                                 EATSPACE();
 206                         } else
 207                                 cmd->a2 = NULL;
 208                 } else
 209                         cmd->a1 = cmd->a2 = NULL;
 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 = 1;
 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 == NULL)
 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                         if (*p == ';') {
 255                                 p++;
 256                                 link = &cmd->next;
 257                                 goto semicolon;
 258                         }
 259                         if (*p)
 260                                 errx(1, "%lu: %s: extra characters at the end of %c command",
 261                                                 linenum, fname, cmd->code);
 262                         break;
 263                 case TEXT:                      /* a c i */
 264                         p++;
 265                         EATSPACE();
 266                         if (*p != '\\')
 267                                 errx(1,
 268 "%lu: %s: command %c expects \\ followed by text", linenum, fname, cmd->code);
 269                         p++;
 270                         EATSPACE();
 271                         if (*p)
 272                                 errx(1,
 273                                 "%lu: %s: extra characters after \\ at the end of %c command",
 274                                 linenum, fname, cmd->code);
 275                         cmd->t = compile_text();
 276                         break;
 277                 case COMMENT:                   /* \0 # */
 278                         break;
 279                 case WFILE:                     /* w */
 280                         p++;
 281                         EATSPACE();
 282                         if (*p == '\0')
 283                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 284                         cmd->t = duptoeol(p, "w command");
 285                         if (aflag)
 286                                 cmd->u.fd = -1;
 287                         else if ((cmd->u.fd = open(p,
 288                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 289                             DEFFILEMODE)) == -1)
 290                                 err(1, "%s", p);
 291                         break;
 292                 case RFILE:                     /* r */
 293                         p++;
 294                         EATSPACE();
 295                         if (*p == '\0')
 296                                 errx(1, "%lu: %s: filename expected", linenum, fname);
 297                         else
 298                                 cmd->t = duptoeol(p, "read command");
 299                         break;
 300                 case BRANCH:                    /* b t */
 301                         p++;
 302                         EATSPACE();
 303                         if (*p == '\0')
 304                                 cmd->t = NULL;
 305                         else
 306                                 cmd->t = duptoeol(p, "branch");
 307                         break;
 308                 case LABEL:                     /* : */
 309                         p++;
 310                         EATSPACE();
 311                         cmd->t = duptoeol(p, "label");
 312                         if (strlen(p) == 0)
 313                                 errx(1, "%lu: %s: empty label", linenum, fname);
 314                         enterlabel(cmd);
 315                         break;
 316                 case SUBST:                     /* s */
 317                         p++;
 318                         if (*p == '\0' || *p == '\\')
 319                                 errx(1,
 320 "%lu: %s: substitute pattern can not be delimited by newline or backslash",
 321                                         linenum, fname);
 322                         if ((cmd->u.s = calloc(1, sizeof(struct s_subst))) == NULL)
 323                                 err(1, "malloc");
 324                         p = compile_delimited(p, re, 0);
 325                         if (p == NULL)
 326                                 errx(1,
 327                                 "%lu: %s: unterminated substitute pattern", linenum, fname);
 328
 329                         /* Compile RE with no case sensitivity temporarily */
 330                         if (*re == '\0')
 331                                 cmd->u.s->re = NULL;
 332                         else
 333                                 cmd->u.s->re = compile_re(re, 0);
 334                         --p;
 335                         p = compile_subst(p, cmd->u.s);
 336                         p = compile_flags(p, cmd->u.s);
 337
 338                         /* Recompile RE with case sensitivity from "I" flag if any */
 339                         if (*re == '\0')
 340                                 cmd->u.s->re = NULL;
 341                         else
 342                                 cmd->u.s->re = compile_re(re, cmd->u.s->icase);
 343                         EATSPACE();
 344                         if (*p == ';') {
 345                                 p++;
 346                                 link = &cmd->next;
 347                                 goto semicolon;
 348                         }
 349                         break;
 350                 case TR:                        /* y */
 351                         p++;
 352                         p = compile_tr(p, &cmd->u.y);
 353                         EATSPACE();
 354                         if (*p == ';') {
 355                                 p++;
 356                                 link = &cmd->next;
 357                                 goto semicolon;
 358                         }
 359                         if (*p)
 360                                 errx(1,
 361 "%lu: %s: extra text at the end of a transform command", linenum, fname);
 362                         break;
 363                 }
 364         }
 365 }
 366
 367 static int
 368 hex2char(const char *in, char *out, int len)
 369 {
 370         long ord;
 371         char *endptr, hexbuf[3];
 372
 373         hexbuf[0] = in[0];
 374         hexbuf[1] = len > 1 ? in[1] : '\0';
 375         hexbuf[2] = '\0';
 376
 377         errno = 0;
 378         ord = strtol(hexbuf, &endptr, 16);
 379         if (*endptr != '\0' || errno != 0)
 380                 return (ERANGE);
 381         *out = (char)ord;
 382         return (0);
 383 }
 384
 385 static bool
 386 hexdigit(char c)
 387 {
 388         int lc;
 389
 390         lc = tolower(c);
 391         return isdigit(lc) || (lc >= 'a' && lc <= 'f');
 392 }
 393
 394 static bool
 395 dohex(const char *in, char *out, int *len)
 396 {
 397         int tmplen;
 398
 399         if (!hexdigit(in[0]))
 400                 return (false);
 401         tmplen = 1;
 402         if (hexdigit(in[1]))
 403                 ++tmplen;
 404         if (hex2char(in, out, tmplen) == 0) {
 405                 *len = tmplen;
 406                 return (true);
 407         }
 408
 409         return (false);
 410 }
 411
 412 /*
 413  * Get a delimited string.  P points to the delimiter of the string; d points
 414  * to a buffer area.  Newline and delimiter escapes are processed; other
 415  * escapes are ignored.
 416  *
 417  * Returns a pointer to the first character after the final delimiter or NULL
 418  * in the case of a non-terminated string.  The character array d is filled
 419  * with the processed string.
 420  */
 421 static char *
 422 compile_delimited(char *p, char *d, int is_tr)
 423 {
 424         int hexlen;
 425         char c;
 426
 427         c = *p++;
 428         if (c == '\0')
 429                 return (NULL);
 430         else if (c == '\\')
 431                 errx(1, "%lu: %s: \\ can not be used as a string delimiter",
 432                                 linenum, fname);
 433         else if (c == '\n')
 434                 errx(1, "%lu: %s: newline can not be used as a string delimiter",
 435                                 linenum, fname);
 436         while (*p) {
 437                 if (*p == '[' && *p != c) {
 438                         if (!is_tr) {
 439                                 if ((d = compile_ccl(&p, d)) == NULL) {
 440                                         errx(1,
 441                                             "%lu: %s: unbalanced brackets ([])",
 442                                             linenum, fname);
 443                                 }
 444                                 continue;
 445                         }
 446                 } else if (*p == '\\' && p[1] == '[') {
 447                         if (is_tr)
 448                                 p++;
 449                         else
 450                                 *d++ = *p++;
 451                 } else if (*p == '\\' && p[1] == c) {
 452                         p++;
 453                 } else if (*p == '\\' &&
 454                     (p[1] == 'n' || p[1] == 'r' || p[1] == 't')) {
 455                         switch (p[1]) {
 456                         case 'n':
 457                                 *d++ = '\n';
 458                                 break;
 459                         case 'r':
 460                                 *d++ = '\r';
 461                                 break;
 462                         case 't':
 463                                 *d++ = '\t';
 464                                 break;
 465                         }
 466                         p += 2;
 467                         continue;
 468                 } else if (*p == '\\' && p[1] == 'x') {
 469                         if (dohex(&p[2], d, &hexlen)) {
 470                                 ++d;
 471                                 p += hexlen + 2;
 472                                 continue;
 473                         }
 474                 } else if (*p == '\\' && p[1] == '\\') {
 475                         if (is_tr)
 476                                 p++;
 477                         else
 478                                 *d++ = *p++;
 479                 } else if (*p == c) {
 480                         *d = '\0';
 481                         return (p + 1);
 482                 }
 483                 *d++ = *p++;
 484         }
 485         return (NULL);
 486 }
 487
 488
 489 /* compile_ccl: expand a POSIX character class */
 490 static char *
 491 compile_ccl(char **sp, char *t)
 492 {
 493         int c, d, hexlen;
 494         char *s = *sp;
 495
 496         *t++ = *s++;
 497         if (*s == '^')
 498                 *t++ = *s++;
 499         if (*s == ']')
 500                 *t++ = *s++;
 501         for (; *s && (*t = *s) != ']'; s++, t++) {
 502                 if (*s == '[' && ((d = *(s+1)) == '.' || d == ':' || d == '=')) {
 503                         *++t = *++s, t++, s++;
 504                         for (c = *s; (*t = *s) != ']' || c != d; s++, t++)
 505                                 if ((c = *s) == '\0')
 506                                         return NULL;
 507                 } else if (*s == '\\') {
 508                         switch (s[1]) {
 509                         case 'n':
 510                                 *t = '\n';
 511                                 s++;
 512                                 break;
 513                         case 'r':
 514                                 *t = '\r';
 515                                 s++;
 516                                 break;
 517                         case 't':
 518                                 *t = '\t';
 519                                 s++;
 520                                 break;
 521                         case 'x':
 522                                 if (dohex(&s[2], t, &hexlen))
 523                                         s += hexlen + 1;
 524                                 break;
 525                         }
 526                 }
 527         }
 528         return (*s == ']') ? *sp = ++s, ++t : NULL;
 529 }
 530
 531 /*
 532  * Compiles the regular expression in RE and returns a pointer to the compiled
 533  * regular expression.
 534  * Cflags are passed to regcomp.
 535  */
 536 static regex_t *
 537 compile_re(char *re, int case_insensitive)
 538 {
 539         regex_t *rep;
 540         int eval, flags;
 541
 542
 543         flags = rflags;
 544         if (case_insensitive)
 545                 flags |= REG_ICASE;
 546         if ((rep = malloc(sizeof(regex_t))) == NULL)
 547                 err(1, "malloc");
 548         if ((eval = regcomp(rep, re, flags)) != 0)
 549                 errx(1, "%lu: %s: RE error: %s",
 550                                 linenum, fname, strregerror(eval, rep));
 551         if (maxnsub < rep->re_nsub)
 552                 maxnsub = rep->re_nsub;
 553         return (rep);
 554 }
 555
 556 /*
 557  * Compile the substitution string of a regular expression and set res to
 558  * point to a saved copy of it.  Nsub is the number of parenthesized regular
 559  * expressions.
 560  */
 561 static char *
 562 compile_subst(char *p, struct s_subst *s)
 563 {
 564         static char lbuf[_POSIX2_LINE_MAX + 1];
 565         int asize, hexlen, size;
 566         u_char ref;
 567         char c, *text, *op, *sp;
 568         int more = 1, sawesc = 0;
 569
 570         c = *p++;                       /* Terminator character */
 571         if (c == '\0')
 572                 return (NULL);
 573
 574         s->maxbref = 0;
 575         s->linenum = linenum;
 576         asize = 2 * _POSIX2_LINE_MAX + 1;
 577         if ((text = malloc(asize)) == NULL)
 578                 err(1, "malloc");
 579         size = 0;
 580         do {
 581                 op = sp = text + size;
 582                 for (; *p; p++) {
 583                         if (*p == '\\' || sawesc) {
 584                                 /*
 585                                  * If this is a continuation from the last
 586                                  * buffer, we won't have a character to
 587                                  * skip over.
 588                                  */
 589                                 if (sawesc)
 590                                         sawesc = 0;
 591                                 else
 592                                         p++;
 593
 594                                 if (*p == '\0') {
 595                                         /*
 596                                          * This escaped character is continued
 597                                          * in the next part of the line.  Note
 598                                          * this fact, then cause the loop to
 599                                          * exit w/ normal EOL case and reenter
 600                                          * above with the new buffer.
 601                                          */
 602                                         sawesc = 1;
 603                                         p--;
 604                                         continue;
 605                                 } else if (strchr("123456789", *p) != NULL) {
 606                                         *sp++ = '\\';
 607                                         ref = *p - '0';
 608                                         if (s->re != NULL &&
 609                                             ref > s->re->re_nsub)
 610                                                 errx(1, "%lu: %s: \\%c not defined in the RE",
 611                                                                 linenum, fname, *p);
 612                                         if (s->maxbref < ref)
 613                                                 s->maxbref = ref;
 614                                 } else {
 615                                         switch (*p) {
 616                                         case '&':
 617                                         case '\\':
 618                                                 *sp++ = '\\';
 619                                                 break;
 620                                         case 'n':
 621                                                 *p = '\n';
 622                                                 break;
 623                                         case 'r':
 624                                                 *p = '\r';
 625                                                 break;
 626                                         case 't':
 627                                                 *p = '\t';
 628                                                 break;
 629                                         case 'x':
 630 #define ADVANCE_N(s, n)                                 \
 631         do {                                            \
 632                 char *adv = (s);                        \
 633                 while (*(adv + (n) - 1) != '\0') {      \
 634                         *adv = *(adv + (n));            \
 635                         ++adv;                          \
 636                 }                                       \
 637                 *adv = '\0';                            \
 638         } while (0);
 639                                                 if (dohex(&p[1], p, &hexlen)) {
 640                                                         ADVANCE_N(p + 1,
 641                                                             hexlen);
 642                                                 }
 643                                                 break;
 644                                         }
 645                                 }
 646                         } else if (*p == c) {
 647                                 if (*++p == '\0' && more) {
 648                                         if (cu_fgets(lbuf, sizeof(lbuf), &more))
 649                                                 p = lbuf;
 650                                 }
 651                                 *sp++ = '\0';
 652                                 size += sp - op;
 653                                 if ((s->new = realloc(text, size)) == NULL)
 654                                         err(1, "realloc");
 655                                 return (p);
 656                         } else if (*p == '\n') {
 657                                 errx(1,
 658 "%lu: %s: unescaped newline inside substitute pattern", linenum, fname);
 659                                 /* NOTREACHED */
 660                         }
 661                         *sp++ = *p;
 662                 }
 663                 size += sp - op;
 664                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 665                         asize *= 2;
 666                         if ((text = realloc(text, asize)) == NULL)
 667                                 err(1, "realloc");
 668                 }
 669         } while (cu_fgets(p = lbuf, sizeof(lbuf), &more) != NULL);
 670         errx(1, "%lu: %s: unterminated substitute in regular expression",
 671                         linenum, fname);
 672         /* NOTREACHED */
 673 }
 674
 675 /*
 676  * Compile the flags of the s command
 677  */
 678 static char *
 679 compile_flags(char *p, struct s_subst *s)
 680 {
 681         int gn;                 /* True if we have seen g or n */
 682         unsigned long nval;
 683         char wfile[_POSIX2_LINE_MAX + 1], *q, *eq;
 684
 685         s->n = 1;                               /* Default */
 686         s->p = 0;
 687         s->wfile = NULL;
 688         s->wfd = -1;
 689         s->icase = 0;
 690         for (gn = 0;;) {
 691                 EATSPACE();                     /* EXTENSION */
 692                 switch (*p) {
 693                 case 'g':
 694                         if (gn)
 695                                 errx(1,
 696 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 697                         gn = 1;
 698                         s->n = 0;
 699                         break;
 700                 case '\0':
 701                 case '\n':
 702                 case ';':
 703                         return (p);
 704                 case 'p':
 705                         s->p = 1;
 706                         break;
 707                 case 'i':
 708                 case 'I':
 709                         s->icase = 1;
 710                         break;
 711                 case '1': case '2': case '3':
 712                 case '4': case '5': case '6':
 713                 case '7': case '8': case '9':
 714                         if (gn)
 715                                 errx(1,
 716 "%lu: %s: more than one number or 'g' in substitute flags", linenum, fname);
 717                         gn = 1;
 718                         errno = 0;
 719                         nval = strtol(p, &p, 10);
 720                         if (errno == ERANGE || nval > INT_MAX)
 721                                 errx(1,
 722 "%lu: %s: overflow in the 'N' substitute flag", linenum, fname);
 723                         s->n = nval;
 724                         p--;
 725                         break;
 726                 case 'w':
 727                         p++;
 728 #ifdef HISTORIC_PRACTICE
 729                         if (*p != ' ') {
 730                                 warnx("%lu: %s: space missing before w wfile", linenum, fname);
 731                                 return (p);
 732                         }
 733 #endif
 734                         EATSPACE();
 735                         q = wfile;
 736                         eq = wfile + sizeof(wfile) - 1;
 737                         while (*p) {
 738                                 if (*p == '\n')
 739                                         break;
 740                                 if (q >= eq)
 741                                         err(1, "wfile too long");
 742                                 *q++ = *p++;
 743                         }
 744                         *q = '\0';
 745                         if (q == wfile)
 746                                 errx(1, "%lu: %s: no wfile specified", linenum, fname);
 747                         s->wfile = strdup(wfile);
 748                         if (!aflag && (s->wfd = open(wfile,
 749                             O_WRONLY|O_APPEND|O_CREAT|O_TRUNC,
 750                             DEFFILEMODE)) == -1)
 751                                 err(1, "%s", wfile);
 752                         return (p);
 753                 default:
 754                         errx(1, "%lu: %s: bad flag in substitute command: '%c'",
 755                                         linenum, fname, *p);
 756                         break;
 757                 }
 758                 p++;
 759         }
 760 }
 761
 762 /*
 763  * Compile a translation set of strings into a lookup table.
 764  */
 765 static char *
 766 compile_tr(char *p, struct s_tr **py)
 767 {
 768         struct s_tr *y;
 769         int i;
 770         const char *op, *np;
 771         char old[_POSIX2_LINE_MAX + 1];
 772         char new[_POSIX2_LINE_MAX + 1];
 773         size_t oclen, oldlen, nclen, newlen;
 774         mbstate_t mbs1, mbs2;
 775
 776         if ((*py = y = malloc(sizeof(*y))) == NULL)
 777                 err(1, NULL);
 778         y->multis = NULL;
 779         y->nmultis = 0;
 780
 781         if (*p == '\0' || *p == '\\')
 782                 errx(1,
 783         "%lu: %s: transform pattern can not be delimited by newline or backslash",
 784                         linenum, fname);
 785         p = compile_delimited(p, old, 1);
 786         if (p == NULL)
 787                 errx(1, "%lu: %s: unterminated transform source string",
 788                                 linenum, fname);
 789         p = compile_delimited(p - 1, new, 1);
 790         if (p == NULL)
 791                 errx(1, "%lu: %s: unterminated transform target string",
 792                                 linenum, fname);
 793         EATSPACE();
 794         op = old;
 795         oldlen = mbsrtowcs(NULL, &op, 0, NULL);
 796         if (oldlen == (size_t)-1)
 797                 err(1, NULL);
 798         np = new;
 799         newlen = mbsrtowcs(NULL, &np, 0, NULL);
 800         if (newlen == (size_t)-1)
 801                 err(1, NULL);
 802         if (newlen != oldlen)
 803                 errx(1, "%lu: %s: transform strings are not the same length",
 804                                 linenum, fname);
 805         if (MB_CUR_MAX == 1) {
 806                 /*
 807                  * The single-byte encoding case is easy: generate a
 808                  * lookup table.
 809                  */
 810                 for (i = 0; i <= UCHAR_MAX; i++)
 811                         y->bytetab[i] = (char)i;
 812                 for (; *op; op++, np++)
 813                         y->bytetab[(u_char)*op] = *np;
 814         } else {
 815                 /*
 816                  * Multi-byte encoding case: generate a lookup table as
 817                  * above, but only for single-byte characters. The first
 818                  * bytes of multi-byte characters have their lookup table
 819                  * entries set to 0, which causes do_tr() to search through
 820                  * an auxiliary vector of multi-byte mappings.
 821                  */
 822                 memset(&mbs1, 0, sizeof(mbs1));
 823                 memset(&mbs2, 0, sizeof(mbs2));
 824                 for (i = 0; i <= UCHAR_MAX; i++)
 825                         y->bytetab[i] = (btowc(i) != WEOF) ? i : 0;
 826                 while (*op != '\0') {
 827                         oclen = mbrlen(op, MB_LEN_MAX, &mbs1);
 828                         if (oclen == (size_t)-1 || oclen == (size_t)-2)
 829                                 errc(1, EILSEQ, NULL);
 830                         nclen = mbrlen(np, MB_LEN_MAX, &mbs2);
 831                         if (nclen == (size_t)-1 || nclen == (size_t)-2)
 832                                 errc(1, EILSEQ, NULL);
 833                         if (oclen == 1 && nclen == 1)
 834                                 y->bytetab[(u_char)*op] = *np;
 835                         else {
 836                                 y->bytetab[(u_char)*op] = 0;
 837                                 y->multis = realloc(y->multis,
 838                                     (y->nmultis + 1) * sizeof(*y->multis));
 839                                 if (y->multis == NULL)
 840                                         err(1, NULL);
 841                                 i = y->nmultis++;
 842                                 y->multis[i].fromlen = oclen;
 843                                 memcpy(y->multis[i].from, op, oclen);
 844                                 y->multis[i].tolen = nclen;
 845                                 memcpy(y->multis[i].to, np, nclen);
 846                         }
 847                         op += oclen;
 848                         np += nclen;
 849                 }
 850         }
 851         return (p);
 852 }
 853
 854 /*
 855  * Compile the text following an a, c, or i command.
 856  */
 857 static char *
 858 compile_text(void)
 859 {
 860         int asize, esc_nl, size;
 861         char *text, *p, *op, *s;
 862         char lbuf[_POSIX2_LINE_MAX + 1];
 863
 864         asize = 2 * _POSIX2_LINE_MAX + 1;
 865         if ((text = malloc(asize)) == NULL)
 866                 err(1, "malloc");
 867         size = 0;
 868         while (cu_fgets(lbuf, sizeof(lbuf), NULL) != NULL) {
 869                 op = s = text + size;
 870                 p = lbuf;
 871 #ifdef LEGACY_BSDSED_COMPAT
 872                 EATSPACE();
 873 #endif
 874                 for (esc_nl = 0; *p != '\0'; p++) {
 875                         if (*p == '\\' && p[1] != '\0' && *++p == '\n')
 876                                 esc_nl = 1;
 877                         *s++ = *p;
 878                 }
 879                 size += s - op;
 880                 if (!esc_nl) {
 881                         *s = '\0';
 882                         break;
 883                 }
 884                 if (asize - size < _POSIX2_LINE_MAX + 1) {
 885                         asize *= 2;
 886                         if ((text = realloc(text, asize)) == NULL)
 887                                 err(1, "realloc");
 888                 }
 889         }
 890         text[size] = '\0';
 891         if ((p = realloc(text, size + 1)) == NULL)
 892                 err(1, "realloc");
 893         return (p);
 894 }
 895
 896 /*
 897  * Get an address and return a pointer to the first character after
 898  * it.  Fill the structure pointed to according to the address.
 899  */
 900 static char *
 901 compile_addr(char *p, struct s_addr *a)
 902 {
 903         char *end, re[_POSIX2_LINE_MAX + 1];
 904         int icase;
 905
 906         icase = 0;
 907
 908         a->type = 0;
 909         switch (*p) {
 910         case '\\':                              /* Context address */
 911                 ++p;
 912                 /* FALLTHROUGH */
 913         case '/':                               /* Context address */
 914                 p = compile_delimited(p, re, 0);
 915                 if (p == NULL)
 916                         errx(1, "%lu: %s: unterminated regular expression", linenum, fname);
 917                 /* Check for case insensitive regexp flag */
 918                 if (*p == 'I') {
 919                         icase = 1;
 920                         p++;
 921                 }
 922                 if (*re == '\0')
 923                         a->u.r = NULL;
 924                 else
 925                         a->u.r = compile_re(re, icase);
 926                 a->type = AT_RE;
 927                 return (p);
 928
 929         case '$':                               /* Last line */
 930                 a->type = AT_LAST;
 931                 return (p + 1);
 932
 933         case '+':                               /* Relative line number */
 934                 a->type = AT_RELLINE;
 935                 p++;
 936                 /* FALLTHROUGH */
 937                                                 /* Line number */
 938         case '0': case '1': case '2': case '3': case '4':
 939         case '5': case '6': case '7': case '8': case '9':
 940                 if (a->type == 0)
 941                         a->type = AT_LINE;
 942                 a->u.l = strtol(p, &end, 10);
 943                 return (end);
 944         default:
 945                 errx(1, "%lu: %s: expected context address", linenum, fname);
 946                 return (NULL);
 947         }
 948 }
 949
 950 /*
 951  * duptoeol --
 952  *      Return a copy of all the characters up to \n or \0.
 953  */
 954 static char *
 955 duptoeol(char *s, const char *ctype)
 956 {
 957         size_t len;
 958         int ws;
 959         char *p, *start;
 960
 961         ws = 0;
 962         for (start = s; *s != '\0' && *s != '\n'; ++s)
 963                 ws = isspace((unsigned char)*s);
 964         *s = '\0';
 965         if (ws)
 966                 warnx("%lu: %s: whitespace after %s", linenum, fname, ctype);
 967         len = s - start + 1;
 968         if ((p = malloc(len)) == NULL)
 969                 err(1, "malloc");
 970         return (memmove(p, start, len));
 971 }
 972
 973 /*
 974  * Convert goto label names to addresses, and count a and r commands, in
 975  * the given subset of the script.  Free the memory used by labels in b
 976  * and t commands (but not by :).
 977  *
 978  * TODO: Remove } nodes
 979  */
 980 static void
 981 fixuplabel(struct s_command *cp, struct s_command *end)
 982 {
 983
 984         for (; cp != end; cp = cp->next)
 985                 switch (cp->code) {
 986                 case 'a':
 987                 case 'r':
 988                         appendnum++;
 989                         break;
 990                 case 'b':
 991                 case 't':
 992                         /* Resolve branch target. */
 993                         if (cp->t == NULL) {
 994                                 cp->u.c = NULL;
 995                                 break;
 996                         }
 997                         if ((cp->u.c = findlabel(cp->t)) == NULL)
 998                                 errx(1, "%lu: %s: undefined label '%s'", linenum, fname, cp->t);
 999                         free(cp->t);
1000                         break;
1001                 case '{':
1002                         /* Do interior commands. */
1003                         fixuplabel(cp->u.c, cp->next);
1004                         break;
1005                 }
1006 }
1007
1008 /*
1009  * Associate the given command label for later lookup.
1010  */
1011 static void
1012 enterlabel(struct s_command *cp)
1013 {
1014         struct labhash **lhp, *lh;
1015         u_char *p;
1016         u_int h, c;
1017
1018         for (h = 0, p = (u_char *)cp->t; (c = *p) != 0; p++)
1019                 h = (h << 5) + h + c;
1020         lhp = &labels[h & LHMASK];
1021         for (lh = *lhp; lh != NULL; lh = lh->lh_next)
1022                 if (lh->lh_hash == h && strcmp(cp->t, lh->lh_cmd->t) == 0)
1023                         errx(1, "%lu: %s: duplicate label '%s'", linenum, fname, cp->t);
1024         if ((lh = malloc(sizeof *lh)) == NULL)
1025                 err(1, "malloc");
1026         lh->lh_next = *lhp;
1027         lh->lh_hash = h;
1028         lh->lh_cmd = cp;
1029         lh->lh_ref = 0;
1030         *lhp = lh;
1031 }
1032
1033 /*
1034  * Find the label contained in the command l in the command linked
1035  * list cp.  L is excluded from the search.  Return NULL if not found.
1036  */
1037 static struct s_command *
1038 findlabel(char *name)
1039 {
1040         struct labhash *lh;
1041         u_char *p;
1042         u_int h, c;
1043
1044         for (h = 0, p = (u_char *)name; (c = *p) != 0; p++)
1045                 h = (h << 5) + h + c;
1046         for (lh = labels[h & LHMASK]; lh != NULL; lh = lh->lh_next) {
1047                 if (lh->lh_hash == h && strcmp(name, lh->lh_cmd->t) == 0) {
1048                         lh->lh_ref = 1;
1049                         return (lh->lh_cmd);
1050                 }
1051         }
1052         return (NULL);
1053 }
1054
1055 /*
1056  * Warn about any unused labels.  As a side effect, release the label hash
1057  * table space.
1058  */
1059 static void
1060 uselabel(void)
1061 {
1062         struct labhash *lh, *next;
1063         int i;
1064
1065         for (i = 0; i < LHSZ; i++) {
1066                 for (lh = labels[i]; lh != NULL; lh = next) {
1067                         next = lh->lh_next;
1068                         if (!lh->lh_ref)
1069                                 warnx("%lu: %s: unused label '%s'",
1070                                     linenum, fname, lh->lh_cmd->t);
1071                         free(lh);
1072                 }
1073         }
1074 }