bin/sh/expand.c

   1 /*-
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1997-2005
   5  *      Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * Kenneth Almquist.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 4. Neither the name of the University nor the names of its contributors
  19  *    may be used to endorse or promote products derived from this software
  20  *    without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #ifndef lint
  36 #if 0
  37 static char sccsid[] = "@(#)expand.c    8.5 (Berkeley) 5/15/95";
  38 #endif
  39 #endif /* not lint */
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 #include <sys/types.h>
  44 #include <sys/time.h>
  45 #include <sys/stat.h>
  46 #include <dirent.h>
  47 #include <errno.h>
  48 #include <inttypes.h>
  49 #include <limits.h>
  50 #include <pwd.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #include <unistd.h>
  55 #include <wchar.h>
  56 #include <wctype.h>
  57
  58 /*
  59  * Routines to expand arguments to commands.  We have to deal with
  60  * backquotes, shell variables, and file metacharacters.
  61  */
  62
  63 #include "shell.h"
  64 #include "main.h"
  65 #include "nodes.h"
  66 #include "eval.h"
  67 #include "expand.h"
  68 #include "syntax.h"
  69 #include "parser.h"
  70 #include "jobs.h"
  71 #include "options.h"
  72 #include "var.h"
  73 #include "input.h"
  74 #include "output.h"
  75 #include "memalloc.h"
  76 #include "error.h"
  77 #include "mystring.h"
  78 #include "arith.h"
  79 #include "show.h"
  80 #include "builtins.h"
  81
  82 /*
  83  * Structure specifying which parts of the string should be searched
  84  * for IFS characters.
  85  */
  86
  87 struct ifsregion {
  88         struct ifsregion *next; /* next region in list */
  89         int begoff;             /* offset of start of region */
  90         int endoff;             /* offset of end of region */
  91         int inquotes;           /* search for nul bytes only */
  92 };
  93
  94
  95 static char *expdest;                   /* output of current string */
  96 static struct nodelist *argbackq;       /* list of back quote expressions */
  97 static struct ifsregion ifsfirst;       /* first struct in list of ifs regions */
  98 static struct ifsregion *ifslastp;      /* last struct in list */
  99 static struct arglist exparg;           /* holds expanded arg list */
 100
 101 static void argstr(char *, int);
 102 static char *exptilde(char *, int);
 103 static void expbackq(union node *, int, int);
 104 static int subevalvar(char *, char *, int, int, int, int, int);
 105 static char *evalvar(char *, int);
 106 static int varisset(char *, int);
 107 static void varvalue(char *, int, int, int);
 108 static void recordregion(int, int, int);
 109 static void removerecordregions(int);
 110 static void ifsbreakup(char *, struct arglist *);
 111 static void expandmeta(struct strlist *, int);
 112 static void expmeta(char *, char *);
 113 static void addfname(char *);
 114 static struct strlist *expsort(struct strlist *);
 115 static struct strlist *msort(struct strlist *, int);
 116 static char *cvtnum(int, char *);
 117 static int collate_range_cmp(wchar_t, wchar_t);
 118
 119 static int
 120 collate_range_cmp(wchar_t c1, wchar_t c2)
 121 {
 122         static wchar_t s1[2], s2[2];
 123
 124         s1[0] = c1;
 125         s2[0] = c2;
 126         return (wcscoll(s1, s2));
 127 }
 128
 129 /*
 130  * Expand shell variables and backquotes inside a here document.
 131  *      union node *arg         the document
 132  *      int fd;                 where to write the expanded version
 133  */
 134
 135 void
 136 expandhere(union node *arg, int fd)
 137 {
 138         expandarg(arg, (struct arglist *)NULL, 0);
 139         xwrite(fd, stackblock(), expdest - stackblock());
 140 }
 141
 142 static char *
 143 stputs_quotes(const char *data, const char *syntax, char *p)
 144 {
 145         while (*data) {
 146                 CHECKSTRSPACE(2, p);
 147                 if (syntax[(int)*data] == CCTL)
 148                         USTPUTC(CTLESC, p);
 149                 USTPUTC(*data++, p);
 150         }
 151         return (p);
 152 }
 153 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
 154
 155 /*
 156  * Perform expansions on an argument, placing the resulting list of arguments
 157  * in arglist.  Parameter expansion, command substitution and arithmetic
 158  * expansion are always performed; additional expansions can be requested
 159  * via flag (EXP_*).
 160  * The result is left in the stack string.
 161  * When arglist is NULL, perform here document expansion.
 162  *
 163  * Caution: this function uses global state and is not reentrant.
 164  * However, a new invocation after an interrupted invocation is safe
 165  * and will reset the global state for the new call.
 166  */
 167 void
 168 expandarg(union node *arg, struct arglist *arglist, int flag)
 169 {
 170         struct strlist *sp;
 171         char *p;
 172
 173         argbackq = arg->narg.backquote;
 174         STARTSTACKSTR(expdest);
 175         ifsfirst.next = NULL;
 176         ifslastp = NULL;
 177         argstr(arg->narg.text, flag);
 178         if (arglist == NULL) {
 179                 STACKSTRNUL(expdest);
 180                 return;                 /* here document expanded */
 181         }
 182         STPUTC('\0', expdest);
 183         p = grabstackstr(expdest);
 184         exparg.lastp = &exparg.list;
 185         /*
 186          * TODO - EXP_REDIR
 187          */
 188         if (flag & EXP_FULL) {
 189                 ifsbreakup(p, &exparg);
 190                 *exparg.lastp = NULL;
 191                 exparg.lastp = &exparg.list;
 192                 expandmeta(exparg.list, flag);
 193         } else {
 194                 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
 195                         rmescapes(p);
 196                 sp = (struct strlist *)stalloc(sizeof (struct strlist));
 197                 sp->text = p;
 198                 *exparg.lastp = sp;
 199                 exparg.lastp = &sp->next;
 200         }
 201         while (ifsfirst.next != NULL) {
 202                 struct ifsregion *ifsp;
 203                 INTOFF;
 204                 ifsp = ifsfirst.next->next;
 205                 ckfree(ifsfirst.next);
 206                 ifsfirst.next = ifsp;
 207                 INTON;
 208         }
 209         *exparg.lastp = NULL;
 210         if (exparg.list) {
 211                 *arglist->lastp = exparg.list;
 212                 arglist->lastp = exparg.lastp;
 213         }
 214 }
 215
 216
 217
 218 /*
 219  * Perform parameter expansion, command substitution and arithmetic
 220  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
 221  * Processing ends at a CTLENDVAR character as well as '\0'.
 222  * This is used to expand word in ${var+word} etc.
 223  * If EXP_FULL, EXP_CASE or EXP_REDIR are set, keep and/or generate CTLESC
 224  * characters to allow for further processing.
 225  * If EXP_FULL is set, also preserve CTLQUOTEMARK characters.
 226  */
 227 static void
 228 argstr(char *p, int flag)
 229 {
 230         char c;
 231         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);  /* do CTLESC */
 232         int firsteq = 1;
 233         int split_lit;
 234         int lit_quoted;
 235
 236         split_lit = flag & EXP_SPLIT_LIT;
 237         lit_quoted = flag & EXP_LIT_QUOTED;
 238         flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
 239         if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
 240                 p = exptilde(p, flag);
 241         for (;;) {
 242                 CHECKSTRSPACE(2, expdest);
 243                 switch (c = *p++) {
 244                 case '\0':
 245                 case CTLENDVAR:
 246                         goto breakloop;
 247                 case CTLQUOTEMARK:
 248                         lit_quoted = 1;
 249                         /* "$@" syntax adherence hack */
 250                         if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
 251                                 break;
 252                         if ((flag & EXP_FULL) != 0)
 253                                 USTPUTC(c, expdest);
 254                         break;
 255                 case CTLQUOTEEND:
 256                         lit_quoted = 0;
 257                         break;
 258                 case CTLESC:
 259                         if (quotes)
 260                                 USTPUTC(c, expdest);
 261                         c = *p++;
 262                         USTPUTC(c, expdest);
 263                         if (split_lit && !lit_quoted)
 264                                 recordregion(expdest - stackblock() -
 265                                     (quotes ? 2 : 1),
 266                                     expdest - stackblock(), 0);
 267                         break;
 268                 case CTLVAR:
 269                         p = evalvar(p, flag);
 270                         break;
 271                 case CTLBACKQ:
 272                 case CTLBACKQ|CTLQUOTE:
 273                         expbackq(argbackq->n, c & CTLQUOTE, flag);
 274                         argbackq = argbackq->next;
 275                         break;
 276                 case CTLENDARI:
 277                         expari(flag);
 278                         break;
 279                 case ':':
 280                 case '=':
 281                         /*
 282                          * sort of a hack - expand tildes in variable
 283                          * assignments (after the first '=' and after ':'s).
 284                          */
 285                         USTPUTC(c, expdest);
 286                         if (split_lit && !lit_quoted)
 287                                 recordregion(expdest - stackblock() - 1,
 288                                     expdest - stackblock(), 0);
 289                         if (flag & EXP_VARTILDE && *p == '~' &&
 290                             (c != '=' || firsteq)) {
 291                                 if (c == '=')
 292                                         firsteq = 0;
 293                                 p = exptilde(p, flag);
 294                         }
 295                         break;
 296                 default:
 297                         USTPUTC(c, expdest);
 298                         if (split_lit && !lit_quoted)
 299                                 recordregion(expdest - stackblock() - 1,
 300                                     expdest - stackblock(), 0);
 301                 }
 302         }
 303 breakloop:;
 304 }
 305
 306 /*
 307  * Perform tilde expansion, placing the result in the stack string and
 308  * returning the next position in the input string to process.
 309  */
 310 static char *
 311 exptilde(char *p, int flag)
 312 {
 313         char c, *startp = p;
 314         struct passwd *pw;
 315         char *home;
 316         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 317
 318         while ((c = *p) != '\0') {
 319                 switch(c) {
 320                 case CTLESC: /* This means CTL* are always considered quoted. */
 321                 case CTLVAR:
 322                 case CTLBACKQ:
 323                 case CTLBACKQ | CTLQUOTE:
 324                 case CTLARI:
 325                 case CTLENDARI:
 326                 case CTLQUOTEMARK:
 327                         return (startp);
 328                 case ':':
 329                         if (flag & EXP_VARTILDE)
 330                                 goto done;
 331                         break;
 332                 case '/':
 333                 case CTLENDVAR:
 334                         goto done;
 335                 }
 336                 p++;
 337         }
 338 done:
 339         *p = '\0';
 340         if (*(startp+1) == '\0') {
 341                 if ((home = lookupvar("HOME")) == NULL)
 342                         goto lose;
 343         } else {
 344                 if ((pw = getpwnam(startp+1)) == NULL)
 345                         goto lose;
 346                 home = pw->pw_dir;
 347         }
 348         if (*home == '\0')
 349                 goto lose;
 350         *p = c;
 351         if (quotes)
 352                 STPUTS_QUOTES(home, SQSYNTAX, expdest);
 353         else
 354                 STPUTS(home, expdest);
 355         return (p);
 356 lose:
 357         *p = c;
 358         return (startp);
 359 }
 360
 361
 362 static void
 363 removerecordregions(int endoff)
 364 {
 365         if (ifslastp == NULL)
 366                 return;
 367
 368         if (ifsfirst.endoff > endoff) {
 369                 while (ifsfirst.next != NULL) {
 370                         struct ifsregion *ifsp;
 371                         INTOFF;
 372                         ifsp = ifsfirst.next->next;
 373                         ckfree(ifsfirst.next);
 374                         ifsfirst.next = ifsp;
 375                         INTON;
 376                 }
 377                 if (ifsfirst.begoff > endoff)
 378                         ifslastp = NULL;
 379                 else {
 380                         ifslastp = &ifsfirst;
 381                         ifsfirst.endoff = endoff;
 382                 }
 383                 return;
 384         }
 385
 386         ifslastp = &ifsfirst;
 387         while (ifslastp->next && ifslastp->next->begoff < endoff)
 388                 ifslastp=ifslastp->next;
 389         while (ifslastp->next != NULL) {
 390                 struct ifsregion *ifsp;
 391                 INTOFF;
 392                 ifsp = ifslastp->next->next;
 393                 ckfree(ifslastp->next);
 394                 ifslastp->next = ifsp;
 395                 INTON;
 396         }
 397         if (ifslastp->endoff > endoff)
 398                 ifslastp->endoff = endoff;
 399 }
 400
 401 /*
 402  * Expand arithmetic expression.  Backup to start of expression,
 403  * evaluate, place result in (backed up) result, adjust string position.
 404  */
 405 void
 406 expari(int flag)
 407 {
 408         char *p, *q, *start;
 409         arith_t result;
 410         int begoff;
 411         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 412         int quoted;
 413
 414         /*
 415          * This routine is slightly over-complicated for
 416          * efficiency.  First we make sure there is
 417          * enough space for the result, which may be bigger
 418          * than the expression.  Next we
 419          * scan backwards looking for the start of arithmetic.  If the
 420          * next previous character is a CTLESC character, then we
 421          * have to rescan starting from the beginning since CTLESC
 422          * characters have to be processed left to right.
 423          */
 424         CHECKSTRSPACE(DIGITS(result) - 2, expdest);
 425         USTPUTC('\0', expdest);
 426         start = stackblock();
 427         p = expdest - 2;
 428         while (p >= start && *p != CTLARI)
 429                 --p;
 430         if (p < start || *p != CTLARI)
 431                 error("missing CTLARI (shouldn't happen)");
 432         if (p > start && *(p - 1) == CTLESC)
 433                 for (p = start; *p != CTLARI; p++)
 434                         if (*p == CTLESC)
 435                                 p++;
 436
 437         if (p[1] == '"')
 438                 quoted=1;
 439         else
 440                 quoted=0;
 441         begoff = p - start;
 442         removerecordregions(begoff);
 443         if (quotes)
 444                 rmescapes(p+2);
 445         q = grabstackstr(expdest);
 446         result = arith(p+2);
 447         ungrabstackstr(q, expdest);
 448         fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result);
 449         while (*p++)
 450                 ;
 451         if (quoted == 0)
 452                 recordregion(begoff, p - 1 - start, 0);
 453         result = expdest - p + 1;
 454         STADJUST(-result, expdest);
 455 }
 456
 457
 458 /*
 459  * Perform command substitution.
 460  */
 461 static void
 462 expbackq(union node *cmd, int quoted, int flag)
 463 {
 464         struct backcmd in;
 465         int i;
 466         char buf[128];
 467         char *p;
 468         char *dest = expdest;
 469         struct ifsregion saveifs, *savelastp;
 470         struct nodelist *saveargbackq;
 471         char lastc;
 472         int startloc = dest - stackblock();
 473         char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
 474         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 475         int nnl;
 476
 477         INTOFF;
 478         saveifs = ifsfirst;
 479         savelastp = ifslastp;
 480         saveargbackq = argbackq;
 481         p = grabstackstr(dest);
 482         evalbackcmd(cmd, &in);
 483         ungrabstackstr(p, dest);
 484         ifsfirst = saveifs;
 485         ifslastp = savelastp;
 486         argbackq = saveargbackq;
 487
 488         p = in.buf;
 489         lastc = '\0';
 490         nnl = 0;
 491         /* Don't copy trailing newlines */
 492         for (;;) {
 493                 if (--in.nleft < 0) {
 494                         if (in.fd < 0)
 495                                 break;
 496                         while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
 497                         TRACE(("expbackq: read returns %d\n", i));
 498                         if (i <= 0)
 499                                 break;
 500                         p = buf;
 501                         in.nleft = i - 1;
 502                 }
 503                 lastc = *p++;
 504                 if (lastc != '\0') {
 505                         if (lastc == '\n') {
 506                                 nnl++;
 507                         } else {
 508                                 CHECKSTRSPACE(nnl + 2, dest);
 509                                 while (nnl > 0) {
 510                                         nnl--;
 511                                         USTPUTC('\n', dest);
 512                                 }
 513                                 if (quotes && syntax[(int)lastc] == CCTL)
 514                                         USTPUTC(CTLESC, dest);
 515                                 USTPUTC(lastc, dest);
 516                         }
 517                 }
 518         }
 519
 520         if (in.fd >= 0)
 521                 close(in.fd);
 522         if (in.buf)
 523                 ckfree(in.buf);
 524         if (in.jp)
 525                 exitstatus = waitforjob(in.jp, (int *)NULL);
 526         if (quoted == 0)
 527                 recordregion(startloc, dest - stackblock(), 0);
 528         TRACE(("expbackq: size=%td: \"%.*s\"\n",
 529                 ((dest - stackblock()) - startloc),
 530                 (int)((dest - stackblock()) - startloc),
 531                 stackblock() + startloc));
 532         expdest = dest;
 533         INTON;
 534 }
 535
 536
 537
 538 static int
 539 subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
 540   int varflags, int quotes)
 541 {
 542         char *startp;
 543         char *loc = NULL;
 544         char *q;
 545         int c = 0;
 546         struct nodelist *saveargbackq = argbackq;
 547         int amount;
 548
 549         argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
 550             subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ?
 551             EXP_CASE : 0) | EXP_TILDE);
 552         STACKSTRNUL(expdest);
 553         argbackq = saveargbackq;
 554         startp = stackblock() + startloc;
 555         if (str == NULL)
 556             str = stackblock() + strloc;
 557
 558         switch (subtype) {
 559         case VSASSIGN:
 560                 setvar(str, startp, 0);
 561                 amount = startp - expdest;
 562                 STADJUST(amount, expdest);
 563                 varflags &= ~VSNUL;
 564                 return 1;
 565
 566         case VSQUESTION:
 567                 if (*p != CTLENDVAR) {
 568                         outfmt(out2, "%s\n", startp);
 569                         error((char *)NULL);
 570                 }
 571                 error("%.*s: parameter %snot set", (int)(p - str - 1),
 572                       str, (varflags & VSNUL) ? "null or "
 573                                               : nullstr);
 574                 return 0;
 575
 576         case VSTRIMLEFT:
 577                 for (loc = startp; loc < str; loc++) {
 578                         c = *loc;
 579                         *loc = '\0';
 580                         if (patmatch(str, startp, quotes)) {
 581                                 *loc = c;
 582                                 goto recordleft;
 583                         }
 584                         *loc = c;
 585                         if (quotes && *loc == CTLESC)
 586                                 loc++;
 587                 }
 588                 return 0;
 589
 590         case VSTRIMLEFTMAX:
 591                 for (loc = str - 1; loc >= startp;) {
 592                         c = *loc;
 593                         *loc = '\0';
 594                         if (patmatch(str, startp, quotes)) {
 595                                 *loc = c;
 596                                 goto recordleft;
 597                         }
 598                         *loc = c;
 599                         loc--;
 600                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
 601                                 for (q = startp; q < loc; q++)
 602                                         if (*q == CTLESC)
 603                                                 q++;
 604                                 if (q > loc)
 605                                         loc--;
 606                         }
 607                 }
 608                 return 0;
 609
 610         case VSTRIMRIGHT:
 611                 for (loc = str - 1; loc >= startp;) {
 612                         if (patmatch(str, loc, quotes)) {
 613                                 amount = loc - expdest;
 614                                 STADJUST(amount, expdest);
 615                                 return 1;
 616                         }
 617                         loc--;
 618                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
 619                                 for (q = startp; q < loc; q++)
 620                                         if (*q == CTLESC)
 621                                                 q++;
 622                                 if (q > loc)
 623                                         loc--;
 624                         }
 625                 }
 626                 return 0;
 627
 628         case VSTRIMRIGHTMAX:
 629                 for (loc = startp; loc < str - 1; loc++) {
 630                         if (patmatch(str, loc, quotes)) {
 631                                 amount = loc - expdest;
 632                                 STADJUST(amount, expdest);
 633                                 return 1;
 634                         }
 635                         if (quotes && *loc == CTLESC)
 636                                 loc++;
 637                 }
 638                 return 0;
 639
 640
 641         default:
 642                 abort();
 643         }
 644
 645 recordleft:
 646         amount = ((str - 1) - (loc - startp)) - expdest;
 647         STADJUST(amount, expdest);
 648         while (loc != str - 1)
 649                 *startp++ = *loc++;
 650         return 1;
 651 }
 652
 653
 654 /*
 655  * Expand a variable, and return a pointer to the next character in the
 656  * input string.
 657  */
 658
 659 static char *
 660 evalvar(char *p, int flag)
 661 {
 662         int subtype;
 663         int varflags;
 664         char *var;
 665         char *val;
 666         int patloc;
 667         int c;
 668         int set;
 669         int special;
 670         int startloc;
 671         int varlen;
 672         int varlenb;
 673         int easy;
 674         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 675
 676         varflags = (unsigned char)*p++;
 677         subtype = varflags & VSTYPE;
 678         var = p;
 679         special = 0;
 680         if (! is_name(*p))
 681                 special = 1;
 682         p = strchr(p, '=') + 1;
 683 again: /* jump here after setting a variable with ${var=text} */
 684         if (varflags & VSLINENO) {
 685                 set = 1;
 686                 special = 0;
 687                 val = var;
 688                 p[-1] = '\0';   /* temporarily overwrite '=' to have \0
 689                                    terminated string */
 690         } else if (special) {
 691                 set = varisset(var, varflags & VSNUL);
 692                 val = NULL;
 693         } else {
 694                 val = bltinlookup(var, 1);
 695                 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
 696                         val = NULL;
 697                         set = 0;
 698                 } else
 699                         set = 1;
 700         }
 701         varlen = 0;
 702         startloc = expdest - stackblock();
 703         if (!set && uflag && *var != '@' && *var != '*') {
 704                 switch (subtype) {
 705                 case VSNORMAL:
 706                 case VSTRIMLEFT:
 707                 case VSTRIMLEFTMAX:
 708                 case VSTRIMRIGHT:
 709                 case VSTRIMRIGHTMAX:
 710                 case VSLENGTH:
 711                         error("%.*s: parameter not set", (int)(p - var - 1),
 712                             var);
 713                 }
 714         }
 715         if (set && subtype != VSPLUS) {
 716                 /* insert the value of the variable */
 717                 if (special) {
 718                         varvalue(var, varflags & VSQUOTE, subtype, flag);
 719                         if (subtype == VSLENGTH) {
 720                                 varlenb = expdest - stackblock() - startloc;
 721                                 varlen = varlenb;
 722                                 if (localeisutf8) {
 723                                         val = stackblock() + startloc;
 724                                         for (;val != expdest; val++)
 725                                                 if ((*val & 0xC0) == 0x80)
 726                                                         varlen--;
 727                                 }
 728                                 STADJUST(-varlenb, expdest);
 729                         }
 730                 } else {
 731                         char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
 732                                                                   : BASESYNTAX;
 733
 734                         if (subtype == VSLENGTH) {
 735                                 for (;*val; val++)
 736                                         if (!localeisutf8 ||
 737                                             (*val & 0xC0) != 0x80)
 738                                                 varlen++;
 739                         }
 740                         else {
 741                                 if (quotes)
 742                                         STPUTS_QUOTES(val, syntax, expdest);
 743                                 else
 744                                         STPUTS(val, expdest);
 745
 746                         }
 747                 }
 748         }
 749
 750         if (subtype == VSPLUS)
 751                 set = ! set;
 752
 753         easy = ((varflags & VSQUOTE) == 0 ||
 754                 (*var == '@' && shellparam.nparam != 1));
 755
 756
 757         switch (subtype) {
 758         case VSLENGTH:
 759                 expdest = cvtnum(varlen, expdest);
 760                 goto record;
 761
 762         case VSNORMAL:
 763                 if (!easy)
 764                         break;
 765 record:
 766                 recordregion(startloc, expdest - stackblock(),
 767                     varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
 768                     (*var == '@' || *var == '*')));
 769                 break;
 770
 771         case VSPLUS:
 772         case VSMINUS:
 773                 if (!set) {
 774                         argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
 775                             (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
 776                         break;
 777                 }
 778                 if (easy)
 779                         goto record;
 780                 break;
 781
 782         case VSTRIMLEFT:
 783         case VSTRIMLEFTMAX:
 784         case VSTRIMRIGHT:
 785         case VSTRIMRIGHTMAX:
 786                 if (!set)
 787                         break;
 788                 /*
 789                  * Terminate the string and start recording the pattern
 790                  * right after it
 791                  */
 792                 STPUTC('\0', expdest);
 793                 patloc = expdest - stackblock();
 794                 if (subevalvar(p, NULL, patloc, subtype,
 795                     startloc, varflags, quotes) == 0) {
 796                         int amount = (expdest - stackblock() - patloc) + 1;
 797                         STADJUST(-amount, expdest);
 798                 }
 799                 /* Remove any recorded regions beyond start of variable */
 800                 removerecordregions(startloc);
 801                 goto record;
 802
 803         case VSASSIGN:
 804         case VSQUESTION:
 805                 if (!set) {
 806                         if (subevalvar(p, var, 0, subtype, startloc, varflags,
 807                             quotes)) {
 808                                 varflags &= ~VSNUL;
 809                                 /*
 810                                  * Remove any recorded regions beyond
 811                                  * start of variable
 812                                  */
 813                                 removerecordregions(startloc);
 814                                 goto again;
 815                         }
 816                         break;
 817                 }
 818                 if (easy)
 819                         goto record;
 820                 break;
 821
 822         case VSERROR:
 823                 c = p - var - 1;
 824                 error("${%.*s%s}: Bad substitution", c, var,
 825                     (c > 0 && *p != CTLENDVAR) ? "..." : "");
 826
 827         default:
 828                 abort();
 829         }
 830         p[-1] = '=';    /* recover overwritten '=' */
 831
 832         if (subtype != VSNORMAL) {      /* skip to end of alternative */
 833                 int nesting = 1;
 834                 for (;;) {
 835                         if ((c = *p++) == CTLESC)
 836                                 p++;
 837                         else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
 838                                 if (set)
 839                                         argbackq = argbackq->next;
 840                         } else if (c == CTLVAR) {
 841                                 if ((*p++ & VSTYPE) != VSNORMAL)
 842                                         nesting++;
 843                         } else if (c == CTLENDVAR) {
 844                                 if (--nesting == 0)
 845                                         break;
 846                         }
 847                 }
 848         }
 849         return p;
 850 }
 851
 852
 853
 854 /*
 855  * Test whether a specialized variable is set.
 856  */
 857
 858 static int
 859 varisset(char *name, int nulok)
 860 {
 861
 862         if (*name == '!')
 863                 return backgndpidset();
 864         else if (*name == '@' || *name == '*') {
 865                 if (*shellparam.p == NULL)
 866                         return 0;
 867
 868                 if (nulok) {
 869                         char **av;
 870
 871                         for (av = shellparam.p; *av; av++)
 872                                 if (**av != '\0')
 873                                         return 1;
 874                         return 0;
 875                 }
 876         } else if (is_digit(*name)) {
 877                 char *ap;
 878                 int num = atoi(name);
 879
 880                 if (num > shellparam.nparam)
 881                         return 0;
 882
 883                 if (num == 0)
 884                         ap = arg0;
 885                 else
 886                         ap = shellparam.p[num - 1];
 887
 888                 if (nulok && (ap == NULL || *ap == '\0'))
 889                         return 0;
 890         }
 891         return 1;
 892 }
 893
 894 static void
 895 strtodest(const char *p, int flag, int subtype, int quoted)
 896 {
 897         if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH)
 898                 STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
 899         else
 900                 STPUTS(p, expdest);
 901 }
 902
 903 /*
 904  * Add the value of a specialized variable to the stack string.
 905  */
 906
 907 static void
 908 varvalue(char *name, int quoted, int subtype, int flag)
 909 {
 910         int num;
 911         char *p;
 912         int i;
 913         char sep;
 914         char **ap;
 915
 916         switch (*name) {
 917         case '$':
 918                 num = rootpid;
 919                 goto numvar;
 920         case '?':
 921                 num = oexitstatus;
 922                 goto numvar;
 923         case '#':
 924                 num = shellparam.nparam;
 925                 goto numvar;
 926         case '!':
 927                 num = backgndpidval();
 928 numvar:
 929                 expdest = cvtnum(num, expdest);
 930                 break;
 931         case '-':
 932                 for (i = 0 ; i < NOPTS ; i++) {
 933                         if (optlist[i].val)
 934                                 STPUTC(optlist[i].letter, expdest);
 935                 }
 936                 break;
 937         case '@':
 938                 if (flag & EXP_FULL && quoted) {
 939                         for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 940                                 strtodest(p, flag, subtype, quoted);
 941                                 if (*ap)
 942                                         STPUTC('\0', expdest);
 943                         }
 944                         break;
 945                 }
 946                 /* FALLTHROUGH */
 947         case '*':
 948                 if (ifsset())
 949                         sep = ifsval()[0];
 950                 else
 951                         sep = ' ';
 952                 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 953                         strtodest(p, flag, subtype, quoted);
 954                         if (!*ap)
 955                                 break;
 956                         if (sep || (flag & EXP_FULL && !quoted && **ap != '\0'))
 957                                 STPUTC(sep, expdest);
 958                 }
 959                 break;
 960         case '0':
 961                 p = arg0;
 962                 strtodest(p, flag, subtype, quoted);
 963                 break;
 964         default:
 965                 if (is_digit(*name)) {
 966                         num = atoi(name);
 967                         if (num > 0 && num <= shellparam.nparam) {
 968                                 p = shellparam.p[num - 1];
 969                                 strtodest(p, flag, subtype, quoted);
 970                         }
 971                 }
 972                 break;
 973         }
 974 }
 975
 976
 977
 978 /*
 979  * Record the fact that we have to scan this region of the
 980  * string for IFS characters.
 981  */
 982
 983 static void
 984 recordregion(int start, int end, int inquotes)
 985 {
 986         struct ifsregion *ifsp;
 987
 988         if (ifslastp == NULL) {
 989                 ifsp = &ifsfirst;
 990         } else {
 991                 if (ifslastp->endoff == start
 992                     && ifslastp->inquotes == inquotes) {
 993                         /* extend previous area */
 994                         ifslastp->endoff = end;
 995                         return;
 996                 }
 997                 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
 998                 ifslastp->next = ifsp;
 999         }
1000         ifslastp = ifsp;
1001         ifslastp->next = NULL;
1002         ifslastp->begoff = start;
1003         ifslastp->endoff = end;
1004         ifslastp->inquotes = inquotes;
1005 }
1006
1007
1008
1009 /*
1010  * Break the argument string into pieces based upon IFS and add the
1011  * strings to the argument list.  The regions of the string to be
1012  * searched for IFS characters have been stored by recordregion.
1013  * CTLESC characters are preserved but have little effect in this pass
1014  * other than escaping CTL* characters.  In particular, they do not escape
1015  * IFS characters: that should be done with the ifsregion mechanism.
1016  * CTLQUOTEMARK characters are used to preserve empty quoted strings.
1017  * This pass treats them as a regular character, making the string non-empty.
1018  * Later, they are removed along with the other CTL* characters.
1019  */
1020 static void
1021 ifsbreakup(char *string, struct arglist *arglist)
1022 {
1023         struct ifsregion *ifsp;
1024         struct strlist *sp;
1025         char *start;
1026         char *p;
1027         char *q;
1028         const char *ifs;
1029         const char *ifsspc;
1030         int had_param_ch = 0;
1031
1032         start = string;
1033
1034         if (ifslastp == NULL) {
1035                 /* Return entire argument, IFS doesn't apply to any of it */
1036                 sp = (struct strlist *)stalloc(sizeof *sp);
1037                 sp->text = start;
1038                 *arglist->lastp = sp;
1039                 arglist->lastp = &sp->next;
1040                 return;
1041         }
1042
1043         ifs = ifsset() ? ifsval() : " \t\n";
1044
1045         for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
1046                 p = string + ifsp->begoff;
1047                 while (p < string + ifsp->endoff) {
1048                         q = p;
1049                         if (*p == CTLESC)
1050                                 p++;
1051                         if (ifsp->inquotes) {
1052                                 /* Only NULs (should be from "$@") end args */
1053                                 had_param_ch = 1;
1054                                 if (*p != 0) {
1055                                         p++;
1056                                         continue;
1057                                 }
1058                                 ifsspc = NULL;
1059                         } else {
1060                                 if (!strchr(ifs, *p)) {
1061                                         had_param_ch = 1;
1062                                         p++;
1063                                         continue;
1064                                 }
1065                                 ifsspc = strchr(" \t\n", *p);
1066
1067                                 /* Ignore IFS whitespace at start */
1068                                 if (q == start && ifsspc != NULL) {
1069                                         p++;
1070                                         start = p;
1071                                         continue;
1072                                 }
1073                                 had_param_ch = 0;
1074                         }
1075
1076                         /* Save this argument... */
1077                         *q = '\0';
1078                         sp = (struct strlist *)stalloc(sizeof *sp);
1079                         sp->text = start;
1080                         *arglist->lastp = sp;
1081                         arglist->lastp = &sp->next;
1082                         p++;
1083
1084                         if (ifsspc != NULL) {
1085                                 /* Ignore further trailing IFS whitespace */
1086                                 for (; p < string + ifsp->endoff; p++) {
1087                                         q = p;
1088                                         if (*p == CTLESC)
1089                                                 p++;
1090                                         if (strchr(ifs, *p) == NULL) {
1091                                                 p = q;
1092                                                 break;
1093                                         }
1094                                         if (strchr(" \t\n", *p) == NULL) {
1095                                                 p++;
1096                                                 break;
1097                                         }
1098                                 }
1099                         }
1100                         start = p;
1101                 }
1102         }
1103
1104         /*
1105          * Save anything left as an argument.
1106          * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
1107          * generating 2 arguments, the second of which is empty.
1108          * Some recent clarification of the Posix spec say that it
1109          * should only generate one....
1110          */
1111         if (had_param_ch || *start != 0) {
1112                 sp = (struct strlist *)stalloc(sizeof *sp);
1113                 sp->text = start;
1114                 *arglist->lastp = sp;
1115                 arglist->lastp = &sp->next;
1116         }
1117 }
1118
1119
1120 static char expdir[PATH_MAX];
1121 #define expdir_end (expdir + sizeof(expdir))
1122
1123 /*
1124  * Perform pathname generation and remove control characters.
1125  * At this point, the only control characters should be CTLESC and CTLQUOTEMARK.
1126  * The results are stored in the list exparg.
1127  */
1128 static void
1129 expandmeta(struct strlist *str, int flag __unused)
1130 {
1131         char *p;
1132         struct strlist **savelastp;
1133         struct strlist *sp;
1134         char c;
1135         /* TODO - EXP_REDIR */
1136
1137         while (str) {
1138                 if (fflag)
1139                         goto nometa;
1140                 p = str->text;
1141                 for (;;) {                      /* fast check for meta chars */
1142                         if ((c = *p++) == '\0')
1143                                 goto nometa;
1144                         if (c == '*' || c == '?' || c == '[')
1145                                 break;
1146                 }
1147                 savelastp = exparg.lastp;
1148                 INTOFF;
1149                 expmeta(expdir, str->text);
1150                 INTON;
1151                 if (exparg.lastp == savelastp) {
1152                         /*
1153                          * no matches
1154                          */
1155 nometa:
1156                         *exparg.lastp = str;
1157                         rmescapes(str->text);
1158                         exparg.lastp = &str->next;
1159                 } else {
1160                         *exparg.lastp = NULL;
1161                         *savelastp = sp = expsort(*savelastp);
1162                         while (sp->next != NULL)
1163                                 sp = sp->next;
1164                         exparg.lastp = &sp->next;
1165                 }
1166                 str = str->next;
1167         }
1168 }
1169
1170
1171 /*
1172  * Do metacharacter (i.e. *, ?, [...]) expansion.
1173  */
1174
1175 static void
1176 expmeta(char *enddir, char *name)
1177 {
1178         char *p;
1179         char *q;
1180         char *start;
1181         char *endname;
1182         int metaflag;
1183         struct stat statb;
1184         DIR *dirp;
1185         struct dirent *dp;
1186         int atend;
1187         int matchdot;
1188         int esc;
1189
1190         metaflag = 0;
1191         start = name;
1192         for (p = name; esc = 0, *p; p += esc + 1) {
1193                 if (*p == '*' || *p == '?')
1194                         metaflag = 1;
1195                 else if (*p == '[') {
1196                         q = p + 1;
1197                         if (*q == '!' || *q == '^')
1198                                 q++;
1199                         for (;;) {
1200                                 while (*q == CTLQUOTEMARK)
1201                                         q++;
1202                                 if (*q == CTLESC)
1203                                         q++;
1204                                 if (*q == '/' || *q == '\0')
1205                                         break;
1206                                 if (*++q == ']') {
1207                                         metaflag = 1;
1208                                         break;
1209                                 }
1210                         }
1211                 } else if (*p == '\0')
1212                         break;
1213                 else if (*p == CTLQUOTEMARK)
1214                         continue;
1215                 else {
1216                         if (*p == CTLESC)
1217                                 esc++;
1218                         if (p[esc] == '/') {
1219                                 if (metaflag)
1220                                         break;
1221                                 start = p + esc + 1;
1222                         }
1223                 }
1224         }
1225         if (metaflag == 0) {    /* we've reached the end of the file name */
1226                 if (enddir != expdir)
1227                         metaflag++;
1228                 for (p = name ; ; p++) {
1229                         if (*p == CTLQUOTEMARK)
1230                                 continue;
1231                         if (*p == CTLESC)
1232                                 p++;
1233                         *enddir++ = *p;
1234                         if (*p == '\0')
1235                                 break;
1236                         if (enddir == expdir_end)
1237                                 return;
1238                 }
1239                 if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1240                         addfname(expdir);
1241                 return;
1242         }
1243         endname = p;
1244         if (start != name) {
1245                 p = name;
1246                 while (p < start) {
1247                         while (*p == CTLQUOTEMARK)
1248                                 p++;
1249                         if (*p == CTLESC)
1250                                 p++;
1251                         *enddir++ = *p++;
1252                         if (enddir == expdir_end)
1253                                 return;
1254                 }
1255         }
1256         if (enddir == expdir) {
1257                 p = ".";
1258         } else if (enddir == expdir + 1 && *expdir == '/') {
1259                 p = "/";
1260         } else {
1261                 p = expdir;
1262                 enddir[-1] = '\0';
1263         }
1264         if ((dirp = opendir(p)) == NULL)
1265                 return;
1266         if (enddir != expdir)
1267                 enddir[-1] = '/';
1268         if (*endname == 0) {
1269                 atend = 1;
1270         } else {
1271                 atend = 0;
1272                 *endname = '\0';
1273                 endname += esc + 1;
1274         }
1275         matchdot = 0;
1276         p = start;
1277         while (*p == CTLQUOTEMARK)
1278                 p++;
1279         if (*p == CTLESC)
1280                 p++;
1281         if (*p == '.')
1282                 matchdot++;
1283         while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1284                 if (dp->d_name[0] == '.' && ! matchdot)
1285                         continue;
1286                 if (patmatch(start, dp->d_name, 0)) {
1287                         if (enddir + dp->d_namlen + 1 > expdir_end)
1288                                 continue;
1289                         memcpy(enddir, dp->d_name, dp->d_namlen + 1);
1290                         if (atend)
1291                                 addfname(expdir);
1292                         else {
1293                                 if (enddir + dp->d_namlen + 2 > expdir_end)
1294                                         continue;
1295                                 enddir[dp->d_namlen] = '/';
1296                                 enddir[dp->d_namlen + 1] = '\0';
1297                                 expmeta(enddir + dp->d_namlen + 1, endname);
1298                         }
1299                 }
1300         }
1301         closedir(dirp);
1302         if (! atend)
1303                 endname[-esc - 1] = esc ? CTLESC : '/';
1304 }
1305
1306
1307 /*
1308  * Add a file name to the list.
1309  */
1310
1311 static void
1312 addfname(char *name)
1313 {
1314         char *p;
1315         struct strlist *sp;
1316
1317         p = stalloc(strlen(name) + 1);
1318         scopy(name, p);
1319         sp = (struct strlist *)stalloc(sizeof *sp);
1320         sp->text = p;
1321         *exparg.lastp = sp;
1322         exparg.lastp = &sp->next;
1323 }
1324
1325
1326 /*
1327  * Sort the results of file name expansion.  It calculates the number of
1328  * strings to sort and then calls msort (short for merge sort) to do the
1329  * work.
1330  */
1331
1332 static struct strlist *
1333 expsort(struct strlist *str)
1334 {
1335         int len;
1336         struct strlist *sp;
1337
1338         len = 0;
1339         for (sp = str ; sp ; sp = sp->next)
1340                 len++;
1341         return msort(str, len);
1342 }
1343
1344
1345 static struct strlist *
1346 msort(struct strlist *list, int len)
1347 {
1348         struct strlist *p, *q = NULL;
1349         struct strlist **lpp;
1350         int half;
1351         int n;
1352
1353         if (len <= 1)
1354                 return list;
1355         half = len >> 1;
1356         p = list;
1357         for (n = half ; --n >= 0 ; ) {
1358                 q = p;
1359                 p = p->next;
1360         }
1361         q->next = NULL;                 /* terminate first half of list */
1362         q = msort(list, half);          /* sort first half of list */
1363         p = msort(p, len - half);               /* sort second half */
1364         lpp = &list;
1365         for (;;) {
1366                 if (strcmp(p->text, q->text) < 0) {
1367                         *lpp = p;
1368                         lpp = &p->next;
1369                         if ((p = *lpp) == NULL) {
1370                                 *lpp = q;
1371                                 break;
1372                         }
1373                 } else {
1374                         *lpp = q;
1375                         lpp = &q->next;
1376                         if ((q = *lpp) == NULL) {
1377                                 *lpp = p;
1378                                 break;
1379                         }
1380                 }
1381         }
1382         return list;
1383 }
1384
1385
1386
1387 static wchar_t
1388 get_wc(const char **p)
1389 {
1390         wchar_t c;
1391         int chrlen;
1392
1393         chrlen = mbtowc(&c, *p, 4);
1394         if (chrlen == 0)
1395                 return 0;
1396         else if (chrlen == -1)
1397                 c = 0;
1398         else
1399                 *p += chrlen;
1400         return c;
1401 }
1402
1403
1404 /*
1405  * See if a character matches a character class, starting at the first colon
1406  * of "[:class:]".
1407  * If a valid character class is recognized, a pointer to the next character
1408  * after the final closing bracket is stored into *end, otherwise a null
1409  * pointer is stored into *end.
1410  */
1411 static int
1412 match_charclass(const char *p, wchar_t chr, const char **end)
1413 {
1414         char name[20];
1415         const char *nameend;
1416         wctype_t cclass;
1417
1418         *end = NULL;
1419         p++;
1420         nameend = strstr(p, ":]");
1421         if (nameend == NULL || nameend - p >= sizeof(name) || nameend == p)
1422                 return 0;
1423         memcpy(name, p, nameend - p);
1424         name[nameend - p] = '\0';
1425         *end = nameend + 2;
1426         cclass = wctype(name);
1427         /* An unknown class matches nothing but is valid nevertheless. */
1428         if (cclass == 0)
1429                 return 0;
1430         return iswctype(chr, cclass);
1431 }
1432
1433
1434 /*
1435  * Returns true if the pattern matches the string.
1436  */
1437
1438 int
1439 patmatch(const char *pattern, const char *string, int squoted)
1440 {
1441         const char *p, *q, *end;
1442         char c;
1443         wchar_t wc, wc2;
1444
1445         p = pattern;
1446         q = string;
1447         for (;;) {
1448                 switch (c = *p++) {
1449                 case '\0':
1450                         goto breakloop;
1451                 case CTLESC:
1452                         if (squoted && *q == CTLESC)
1453                                 q++;
1454                         if (*q++ != *p++)
1455                                 return 0;
1456                         break;
1457                 case CTLQUOTEMARK:
1458                         continue;
1459                 case '?':
1460                         if (squoted && *q == CTLESC)
1461                                 q++;
1462                         if (localeisutf8)
1463                                 wc = get_wc(&q);
1464                         else
1465                                 wc = (unsigned char)*q++;
1466                         if (wc == '\0')
1467                                 return 0;
1468                         break;
1469                 case '*':
1470                         c = *p;
1471                         while (c == CTLQUOTEMARK || c == '*')
1472                                 c = *++p;
1473                         if (c != CTLESC &&  c != CTLQUOTEMARK &&
1474                             c != '?' && c != '*' && c != '[') {
1475                                 while (*q != c) {
1476                                         if (squoted && *q == CTLESC &&
1477                                             q[1] == c)
1478                                                 break;
1479                                         if (*q == '\0')
1480                                                 return 0;
1481                                         if (squoted && *q == CTLESC)
1482                                                 q++;
1483                                         q++;
1484                                 }
1485                         }
1486                         do {
1487                                 if (patmatch(p, q, squoted))
1488                                         return 1;
1489                                 if (squoted && *q == CTLESC)
1490                                         q++;
1491                         } while (*q++ != '\0');
1492                         return 0;
1493                 case '[': {
1494                         const char *endp;
1495                         int invert, found;
1496                         wchar_t chr;
1497
1498                         endp = p;
1499                         if (*endp == '!' || *endp == '^')
1500                                 endp++;
1501                         for (;;) {
1502                                 while (*endp == CTLQUOTEMARK)
1503                                         endp++;
1504                                 if (*endp == '\0')
1505                                         goto dft;               /* no matching ] */
1506                                 if (*endp == CTLESC)
1507                                         endp++;
1508                                 if (*++endp == ']')
1509                                         break;
1510                         }
1511                         invert = 0;
1512                         if (*p == '!' || *p == '^') {
1513                                 invert++;
1514                                 p++;
1515                         }
1516                         found = 0;
1517                         if (squoted && *q == CTLESC)
1518                                 q++;
1519                         if (localeisutf8)
1520                                 chr = get_wc(&q);
1521                         else
1522                                 chr = (unsigned char)*q++;
1523                         if (chr == '\0')
1524                                 return 0;
1525                         c = *p++;
1526                         do {
1527                                 if (c == CTLQUOTEMARK)
1528                                         continue;
1529                                 if (c == '[' && *p == ':') {
1530                                         found |= match_charclass(p, chr, &end);
1531                                         if (end != NULL)
1532                                                 p = end;
1533                                 }
1534                                 if (c == CTLESC)
1535                                         c = *p++;
1536                                 if (localeisutf8 && c & 0x80) {
1537                                         p--;
1538                                         wc = get_wc(&p);
1539                                         if (wc == 0) /* bad utf-8 */
1540                                                 return 0;
1541                                 } else
1542                                         wc = (unsigned char)c;
1543                                 if (*p == '-' && p[1] != ']') {
1544                                         p++;
1545                                         while (*p == CTLQUOTEMARK)
1546                                                 p++;
1547                                         if (*p == CTLESC)
1548                                                 p++;
1549                                         if (localeisutf8) {
1550                                                 wc2 = get_wc(&p);
1551                                                 if (wc2 == 0) /* bad utf-8 */
1552                                                         return 0;
1553                                         } else
1554                                                 wc2 = (unsigned char)*p++;
1555                                         if (   collate_range_cmp(chr, wc) >= 0
1556                                             && collate_range_cmp(chr, wc2) <= 0
1557                                            )
1558                                                 found = 1;
1559                                 } else {
1560                                         if (chr == wc)
1561                                                 found = 1;
1562                                 }
1563                         } while ((c = *p++) != ']');
1564                         if (found == invert)
1565                                 return 0;
1566                         break;
1567                 }
1568 dft:            default:
1569                         if (squoted && *q == CTLESC)
1570                                 q++;
1571                         if (*q++ != c)
1572                                 return 0;
1573                         break;
1574                 }
1575         }
1576 breakloop:
1577         if (*q != '\0')
1578                 return 0;
1579         return 1;
1580 }
1581
1582
1583
1584 /*
1585  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1586  */
1587
1588 void
1589 rmescapes(char *str)
1590 {
1591         char *p, *q;
1592
1593         p = str;
1594         while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1595                 if (*p++ == '\0')
1596                         return;
1597         }
1598         q = p;
1599         while (*p) {
1600                 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1601                         p++;
1602                         continue;
1603                 }
1604                 if (*p == CTLESC)
1605                         p++;
1606                 *q++ = *p++;
1607         }
1608         *q = '\0';
1609 }
1610
1611
1612
1613 /*
1614  * See if a pattern matches in a case statement.
1615  */
1616
1617 int
1618 casematch(union node *pattern, const char *val)
1619 {
1620         struct stackmark smark;
1621         int result;
1622         char *p;
1623
1624         setstackmark(&smark);
1625         argbackq = pattern->narg.backquote;
1626         STARTSTACKSTR(expdest);
1627         ifslastp = NULL;
1628         argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1629         STPUTC('\0', expdest);
1630         p = grabstackstr(expdest);
1631         result = patmatch(p, val, 0);
1632         popstackmark(&smark);
1633         return result;
1634 }
1635
1636 /*
1637  * Our own itoa().
1638  */
1639
1640 static char *
1641 cvtnum(int num, char *buf)
1642 {
1643         char temp[32];
1644         int neg = num < 0;
1645         char *p = temp + 31;
1646
1647         temp[31] = '\0';
1648
1649         do {
1650                 *--p = num % 10 + '0';
1651         } while ((num /= 10) != 0);
1652
1653         if (neg)
1654                 *--p = '-';
1655
1656         STPUTS(p, buf);
1657         return buf;
1658 }
1659
1660 /*
1661  * Do most of the work for wordexp(3).
1662  */
1663
1664 int
1665 wordexpcmd(int argc, char **argv)
1666 {
1667         size_t len;
1668         int i;
1669
1670         out1fmt("%08x", argc - 1);
1671         for (i = 1, len = 0; i < argc; i++)
1672                 len += strlen(argv[i]);
1673         out1fmt("%08x", (int)len);
1674         for (i = 1; i < argc; i++)
1675                 outbin(argv[i], strlen(argv[i]) + 1, out1);
1676         return (0);
1677 }