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  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  * @(#)expand.c 8.5 (Berkeley) 5/15/95
  39  * $FreeBSD: src/bin/sh/expand.c,v 1.90 2011/06/13 21:03:27 jilles Exp $
  40  */
  41
  42 #include <sys/types.h>
  43 #include <sys/time.h>
  44 #include <sys/stat.h>
  45 #include <dirent.h>
  46 #include <errno.h>
  47 #include <inttypes.h>
  48 #include <limits.h>
  49 #include <pwd.h>
  50 #include <stdio.h>
  51 #include <stdlib.h>
  52 #include <string.h>
  53 #include <unistd.h>
  54 #include <wchar.h>
  55
  56 /*
  57  * Routines to expand arguments to commands.  We have to deal with
  58  * backquotes, shell variables, and file metacharacters.
  59  */
  60
  61 #include "shell.h"
  62 #include "main.h"
  63 #include "nodes.h"
  64 #include "eval.h"
  65 #include "expand.h"
  66 #include "syntax.h"
  67 #include "parser.h"
  68 #include "jobs.h"
  69 #include "options.h"
  70 #include "var.h"
  71 #include "input.h"
  72 #include "output.h"
  73 #include "memalloc.h"
  74 #include "error.h"
  75 #include "mystring.h"
  76 #include "arith.h"
  77 #include "show.h"
  78 #include "builtins.h"
  79
  80 /*
  81  * Structure specifying which parts of the string should be searched
  82  * for IFS characters.
  83  */
  84
  85 struct ifsregion {
  86         struct ifsregion *next; /* next region in list */
  87         int begoff;             /* offset of start of region */
  88         int endoff;             /* offset of end of region */
  89         int inquotes;           /* search for nul bytes only */
  90 };
  91
  92
  93 static char *expdest;                   /* output of current string */
  94 static struct nodelist *argbackq;       /* list of back quote expressions */
  95 static struct ifsregion ifsfirst;       /* first struct in list of ifs regions */
  96 static struct ifsregion *ifslastp;      /* last struct in list */
  97 static struct arglist exparg;           /* holds expanded arg list */
  98
  99 static void argstr(char *, int);
 100 static char *exptilde(char *, int);
 101 static void expbackq(union node *, int, int);
 102 static int subevalvar(char *, char *, int, int, int, int, int);
 103 static char *evalvar(char *, int);
 104 static int varisset(char *, int);
 105 static void varvalue(char *, int, int, int);
 106 static void recordregion(int, int, int);
 107 static void removerecordregions(int);
 108 static void ifsbreakup(char *, struct arglist *);
 109 static void expandmeta(struct strlist *, int);
 110 static void expmeta(char *, char *);
 111 static void addfname(char *);
 112 static struct strlist *expsort(struct strlist *);
 113 static struct strlist *msort(struct strlist *, int);
 114 static char *cvtnum(int, char *);
 115 static int collate_range_cmp(wchar_t, wchar_t);
 116
 117 static int
 118 collate_range_cmp(wchar_t c1, wchar_t c2)
 119 {
 120         static wchar_t s1[2], s2[2];
 121
 122         s1[0] = c1;
 123         s2[0] = c2;
 124         return (wcscoll(s1, s2));
 125 }
 126
 127 /*
 128  * Expand shell variables and backquotes inside a here document.
 129  *      union node *arg         the document
 130  *      int fd;                 where to write the expanded version
 131  */
 132
 133 void
 134 expandhere(union node *arg, int fd)
 135 {
 136         expandarg(arg, NULL, 0);
 137         xwrite(fd, stackblock(), expdest - stackblock());
 138 }
 139
 140 static char *
 141 stputs_quotes(const char *data, const char *syntax, char *p)
 142 {
 143         while (*data) {
 144                 CHECKSTRSPACE(2, p);
 145                 if (syntax[(int)*data] == CCTL)
 146                         USTPUTC(CTLESC, p);
 147                 USTPUTC(*data++, p);
 148         }
 149         return (p);
 150 }
 151 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
 152
 153 /*
 154  * Perform expansions on an argument, placing the resulting list of arguments
 155  * in arglist.  Parameter expansion, command substitution and arithmetic
 156  * expansion are always performed; additional expansions can be requested
 157  * via flag (EXP_*).
 158  * The result is left in the stack string.
 159  * When arglist is NULL, perform here document expansion.
 160  *
 161  * Caution: this function uses global state and is not reentrant.
 162  * However, a new invocation after an interrupted invocation is safe
 163  * and will reset the global state for the new call.
 164  */
 165 void
 166 expandarg(union node *arg, struct arglist *arglist, int flag)
 167 {
 168         struct strlist *sp;
 169         char *p;
 170
 171         argbackq = arg->narg.backquote;
 172         STARTSTACKSTR(expdest);
 173         ifsfirst.next = NULL;
 174         ifslastp = NULL;
 175         argstr(arg->narg.text, flag);
 176         if (arglist == NULL) {
 177                 STACKSTRNUL(expdest);
 178                 return;                 /* here document expanded */
 179         }
 180         STPUTC('\0', expdest);
 181         p = grabstackstr(expdest);
 182         exparg.lastp = &exparg.list;
 183         /*
 184          * TODO - EXP_REDIR
 185          */
 186         if (flag & EXP_FULL) {
 187                 ifsbreakup(p, &exparg);
 188                 *exparg.lastp = NULL;
 189                 exparg.lastp = &exparg.list;
 190                 expandmeta(exparg.list, flag);
 191         } else {
 192                 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
 193                         rmescapes(p);
 194                 sp = (struct strlist *)stalloc(sizeof (struct strlist));
 195                 sp->text = p;
 196                 *exparg.lastp = sp;
 197                 exparg.lastp = &sp->next;
 198         }
 199         while (ifsfirst.next != NULL) {
 200                 struct ifsregion *ifsp;
 201                 INTOFF;
 202                 ifsp = ifsfirst.next->next;
 203                 ckfree(ifsfirst.next);
 204                 ifsfirst.next = ifsp;
 205                 INTON;
 206         }
 207         *exparg.lastp = NULL;
 208         if (exparg.list) {
 209                 *arglist->lastp = exparg.list;
 210                 arglist->lastp = exparg.lastp;
 211         }
 212 }
 213
 214
 215
 216 /*
 217  * Perform parameter expansion, command substitution and arithmetic
 218  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
 219  * Processing ends at a CTLENDVAR character as well as '\0'.
 220  * This is used to expand word in ${var+word} etc.
 221  * If EXP_FULL, EXP_CASE or EXP_REDIR are set, keep and/or generate CTLESC
 222  * characters to allow for further processing.
 223  * If EXP_FULL is set, also preserve CTLQUOTEMARK characters.
 224  */
 225 static void
 226 argstr(char *p, int flag)
 227 {
 228         char c;
 229         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);  /* do CTLESC */
 230         int firsteq = 1;
 231         int split_lit;
 232         int lit_quoted;
 233
 234         split_lit = flag & EXP_SPLIT_LIT;
 235         lit_quoted = flag & EXP_LIT_QUOTED;
 236         flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
 237         if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
 238                 p = exptilde(p, flag);
 239         for (;;) {
 240                 CHECKSTRSPACE(2, expdest);
 241                 switch (c = *p++) {
 242                 case '\0':
 243                 case CTLENDVAR:
 244                         goto breakloop;
 245                 case CTLQUOTEMARK:
 246                         lit_quoted = 1;
 247                         /* "$@" syntax adherence hack */
 248                         if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
 249                                 break;
 250                         if ((flag & EXP_FULL) != 0)
 251                                 USTPUTC(c, expdest);
 252                         break;
 253                 case CTLQUOTEEND:
 254                         lit_quoted = 0;
 255                         break;
 256                 case CTLESC:
 257                         if (quotes)
 258                                 USTPUTC(c, expdest);
 259                         c = *p++;
 260                         USTPUTC(c, expdest);
 261                         if (split_lit && !lit_quoted)
 262                                 recordregion(expdest - stackblock() -
 263                                     (quotes ? 2 : 1),
 264                                     expdest - stackblock(), 0);
 265                         break;
 266                 case CTLVAR:
 267                         p = evalvar(p, flag);
 268                         break;
 269                 case CTLBACKQ:
 270                 case CTLBACKQ|CTLQUOTE:
 271                         expbackq(argbackq->n, c & CTLQUOTE, flag);
 272                         argbackq = argbackq->next;
 273                         break;
 274                 case CTLENDARI:
 275                         expari(flag);
 276                         break;
 277                 case ':':
 278                 case '=':
 279                         /*
 280                          * sort of a hack - expand tildes in variable
 281                          * assignments (after the first '=' and after ':'s).
 282                          */
 283                         USTPUTC(c, expdest);
 284                         if (split_lit && !lit_quoted)
 285                                 recordregion(expdest - stackblock() - 1,
 286                                     expdest - stackblock(), 0);
 287                         if (flag & EXP_VARTILDE && *p == '~' &&
 288                             (c != '=' || firsteq)) {
 289                                 if (c == '=')
 290                                         firsteq = 0;
 291                                 p = exptilde(p, flag);
 292                         }
 293                         break;
 294                 default:
 295                         USTPUTC(c, expdest);
 296                         if (split_lit && !lit_quoted)
 297                                 recordregion(expdest - stackblock() - 1,
 298                                     expdest - stackblock(), 0);
 299                 }
 300         }
 301 breakloop:;
 302 }
 303
 304 /*
 305  * Perform tilde expansion, placing the result in the stack string and
 306  * returning the next position in the input string to process.
 307  */
 308 static char *
 309 exptilde(char *p, int flag)
 310 {
 311         char c, *startp = p;
 312         struct passwd *pw;
 313         char *home;
 314         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 315
 316         while ((c = *p) != '\0') {
 317                 switch(c) {
 318                 case CTLESC: /* This means CTL* are always considered quoted. */
 319                 case CTLVAR:
 320                 case CTLBACKQ:
 321                 case CTLBACKQ | CTLQUOTE:
 322                 case CTLARI:
 323                 case CTLENDARI:
 324                 case CTLQUOTEMARK:
 325                         return (startp);
 326                 case ':':
 327                         if (flag & EXP_VARTILDE)
 328                                 goto done;
 329                         break;
 330                 case '/':
 331                 case CTLENDVAR:
 332                         goto done;
 333                 }
 334                 p++;
 335         }
 336 done:
 337         *p = '\0';
 338         if (*(startp+1) == '\0') {
 339                 if ((home = lookupvar("HOME")) == NULL)
 340                         goto lose;
 341         } else {
 342                 if ((pw = getpwnam(startp+1)) == NULL)
 343                         goto lose;
 344                 home = pw->pw_dir;
 345         }
 346         if (*home == '\0')
 347                 goto lose;
 348         *p = c;
 349         if (quotes)
 350                 STPUTS_QUOTES(home, SQSYNTAX, expdest);
 351         else
 352                 STPUTS(home, expdest);
 353         return (p);
 354 lose:
 355         *p = c;
 356         return (startp);
 357 }
 358
 359
 360 static void
 361 removerecordregions(int endoff)
 362 {
 363         if (ifslastp == NULL)
 364                 return;
 365
 366         if (ifsfirst.endoff > endoff) {
 367                 while (ifsfirst.next != NULL) {
 368                         struct ifsregion *ifsp;
 369                         INTOFF;
 370                         ifsp = ifsfirst.next->next;
 371                         ckfree(ifsfirst.next);
 372                         ifsfirst.next = ifsp;
 373                         INTON;
 374                 }
 375                 if (ifsfirst.begoff > endoff)
 376                         ifslastp = NULL;
 377                 else {
 378                         ifslastp = &ifsfirst;
 379                         ifsfirst.endoff = endoff;
 380                 }
 381                 return;
 382         }
 383
 384         ifslastp = &ifsfirst;
 385         while (ifslastp->next && ifslastp->next->begoff < endoff)
 386                 ifslastp=ifslastp->next;
 387         while (ifslastp->next != NULL) {
 388                 struct ifsregion *ifsp;
 389                 INTOFF;
 390                 ifsp = ifslastp->next->next;
 391                 ckfree(ifslastp->next);
 392                 ifslastp->next = ifsp;
 393                 INTON;
 394         }
 395         if (ifslastp->endoff > endoff)
 396                 ifslastp->endoff = endoff;
 397 }
 398
 399 /*
 400  * Expand arithmetic expression.  Backup to start of expression,
 401  * evaluate, place result in (backed up) result, adjust string position.
 402  */
 403 void
 404 expari(int flag)
 405 {
 406         char *p, *q, *start;
 407         arith_t result;
 408         int begoff;
 409         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 410         int quoted;
 411
 412         /*
 413          * This routine is slightly over-complicated for
 414          * efficiency.  First we make sure there is
 415          * enough space for the result, which may be bigger
 416          * than the expression.  Next we
 417          * scan backwards looking for the start of arithmetic.  If the
 418          * next previous character is a CTLESC character, then we
 419          * have to rescan starting from the beginning since CTLESC
 420          * characters have to be processed left to right.
 421          */
 422         CHECKSTRSPACE(DIGITS(result) - 2, expdest);
 423         USTPUTC('\0', expdest);
 424         start = stackblock();
 425         p = expdest - 2;
 426         while (p >= start && *p != CTLARI)
 427                 --p;
 428         if (p < start || *p != CTLARI)
 429                 error("missing CTLARI (shouldn't happen)");
 430         if (p > start && *(p - 1) == CTLESC)
 431                 for (p = start; *p != CTLARI; p++)
 432                         if (*p == CTLESC)
 433                                 p++;
 434
 435         if (p[1] == '"')
 436                 quoted=1;
 437         else
 438                 quoted=0;
 439         begoff = p - start;
 440         removerecordregions(begoff);
 441         if (quotes)
 442                 rmescapes(p+2);
 443         q = grabstackstr(expdest);
 444         result = arith(p+2);
 445         ungrabstackstr(q, expdest);
 446         fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result);
 447         while (*p++)
 448                 ;
 449         if (quoted == 0)
 450                 recordregion(begoff, p - 1 - start, 0);
 451         result = expdest - p + 1;
 452         STADJUST(-result, expdest);
 453 }
 454
 455
 456 /*
 457  * Perform command substitution.
 458  */
 459 static void
 460 expbackq(union node *cmd, int quoted, int flag)
 461 {
 462         struct backcmd in;
 463         int i;
 464         char buf[128];
 465         char *p;
 466         char *dest = expdest;
 467         struct ifsregion saveifs, *savelastp;
 468         struct nodelist *saveargbackq;
 469         char lastc;
 470         int startloc = dest - stackblock();
 471         char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
 472         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 473         int nnl;
 474
 475         INTOFF;
 476         saveifs = ifsfirst;
 477         savelastp = ifslastp;
 478         saveargbackq = argbackq;
 479         p = grabstackstr(dest);
 480         evalbackcmd(cmd, &in);
 481         ungrabstackstr(p, dest);
 482         ifsfirst = saveifs;
 483         ifslastp = savelastp;
 484         argbackq = saveargbackq;
 485
 486         p = in.buf;
 487         lastc = '\0';
 488         nnl = 0;
 489         /* Don't copy trailing newlines */
 490         for (;;) {
 491                 if (--in.nleft < 0) {
 492                         if (in.fd < 0)
 493                                 break;
 494                         while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
 495                         TRACE(("expbackq: read returns %d\n", i));
 496                         if (i <= 0)
 497                                 break;
 498                         p = buf;
 499                         in.nleft = i - 1;
 500                 }
 501                 lastc = *p++;
 502                 if (lastc != '\0') {
 503                         if (lastc == '\n') {
 504                                 nnl++;
 505                         } else {
 506                                 CHECKSTRSPACE(nnl + 2, dest);
 507                                 while (nnl > 0) {
 508                                         nnl--;
 509                                         USTPUTC('\n', dest);
 510                                 }
 511                                 if (quotes && syntax[(int)lastc] == CCTL)
 512                                         USTPUTC(CTLESC, dest);
 513                                 USTPUTC(lastc, dest);
 514                         }
 515                 }
 516         }
 517
 518         if (in.fd >= 0)
 519                 close(in.fd);
 520         if (in.buf)
 521                 ckfree(in.buf);
 522         if (in.jp)
 523                 exitstatus = waitforjob(in.jp, NULL);
 524         if (quoted == 0)
 525                 recordregion(startloc, dest - stackblock(), 0);
 526         TRACE(("expbackq: size=%td: \"%.*s\"\n",
 527                 ((dest - stackblock()) - startloc),
 528                 (int)((dest - stackblock()) - startloc),
 529                 stackblock() + startloc));
 530         expdest = dest;
 531         INTON;
 532 }
 533
 534
 535
 536 static int
 537 subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
 538   int varflags, int quotes)
 539 {
 540         char *startp;
 541         char *loc = NULL;
 542         char *q;
 543         int c = 0;
 544         struct nodelist *saveargbackq = argbackq;
 545         int amount;
 546
 547         argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
 548             subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ?
 549             EXP_CASE : 0) | EXP_TILDE);
 550         STACKSTRNUL(expdest);
 551         argbackq = saveargbackq;
 552         startp = stackblock() + startloc;
 553         if (str == NULL)
 554             str = stackblock() + strloc;
 555
 556         switch (subtype) {
 557         case VSASSIGN:
 558                 setvar(str, startp, 0);
 559                 amount = startp - expdest;
 560                 STADJUST(amount, expdest);
 561                 varflags &= ~VSNUL;
 562                 return 1;
 563
 564         case VSQUESTION:
 565                 if (*p != CTLENDVAR) {
 566                         outfmt(out2, "%s\n", startp);
 567                         error(NULL);
 568                 }
 569                 error("%.*s: parameter %snot set", (int)(p - str - 1),
 570                       str, (varflags & VSNUL) ? "null or "
 571                                               : nullstr);
 572                 return 0;
 573
 574         case VSTRIMLEFT:
 575                 for (loc = startp; loc < str; loc++) {
 576                         c = *loc;
 577                         *loc = '\0';
 578                         if (patmatch(str, startp, quotes)) {
 579                                 *loc = c;
 580                                 goto recordleft;
 581                         }
 582                         *loc = c;
 583                         if (quotes && *loc == CTLESC)
 584                                 loc++;
 585                 }
 586                 return 0;
 587
 588         case VSTRIMLEFTMAX:
 589                 for (loc = str - 1; loc >= startp;) {
 590                         c = *loc;
 591                         *loc = '\0';
 592                         if (patmatch(str, startp, quotes)) {
 593                                 *loc = c;
 594                                 goto recordleft;
 595                         }
 596                         *loc = c;
 597                         loc--;
 598                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
 599                                 for (q = startp; q < loc; q++)
 600                                         if (*q == CTLESC)
 601                                                 q++;
 602                                 if (q > loc)
 603                                         loc--;
 604                         }
 605                 }
 606                 return 0;
 607
 608         case VSTRIMRIGHT:
 609                 for (loc = str - 1; loc >= startp;) {
 610                         if (patmatch(str, loc, quotes)) {
 611                                 amount = loc - expdest;
 612                                 STADJUST(amount, expdest);
 613                                 return 1;
 614                         }
 615                         loc--;
 616                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
 617                                 for (q = startp; q < loc; q++)
 618                                         if (*q == CTLESC)
 619                                                 q++;
 620                                 if (q > loc)
 621                                         loc--;
 622                         }
 623                 }
 624                 return 0;
 625
 626         case VSTRIMRIGHTMAX:
 627                 for (loc = startp; loc < str - 1; loc++) {
 628                         if (patmatch(str, loc, quotes)) {
 629                                 amount = loc - expdest;
 630                                 STADJUST(amount, expdest);
 631                                 return 1;
 632                         }
 633                         if (quotes && *loc == CTLESC)
 634                                 loc++;
 635                 }
 636                 return 0;
 637
 638
 639         default:
 640                 abort();
 641         }
 642
 643 recordleft:
 644         amount = ((str - 1) - (loc - startp)) - expdest;
 645         STADJUST(amount, expdest);
 646         while (loc != str - 1)
 647                 *startp++ = *loc++;
 648         return 1;
 649 }
 650
 651
 652 /*
 653  * Expand a variable, and return a pointer to the next character in the
 654  * input string.
 655  */
 656
 657 static char *
 658 evalvar(char *p, int flag)
 659 {
 660         int subtype;
 661         int varflags;
 662         char *var;
 663         char *val;
 664         int patloc;
 665         int c;
 666         int set;
 667         int special;
 668         int startloc;
 669         int varlen;
 670         int varlenb;
 671         int easy;
 672         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
 673
 674         varflags = (unsigned char)*p++;
 675         subtype = varflags & VSTYPE;
 676         var = p;
 677         special = 0;
 678         if (! is_name(*p))
 679                 special = 1;
 680         p = strchr(p, '=') + 1;
 681 again: /* jump here after setting a variable with ${var=text} */
 682         if (varflags & VSLINENO) {
 683                 set = 1;
 684                 special = 0;
 685                 val = var;
 686                 p[-1] = '\0';   /* temporarily overwrite '=' to have \0
 687                                    terminated string */
 688         } else if (special) {
 689                 set = varisset(var, varflags & VSNUL);
 690                 val = NULL;
 691         } else {
 692                 val = bltinlookup(var, 1);
 693                 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
 694                         val = NULL;
 695                         set = 0;
 696                 } else
 697                         set = 1;
 698         }
 699         varlen = 0;
 700         startloc = expdest - stackblock();
 701         if (!set && uflag && *var != '@' && *var != '*') {
 702                 switch (subtype) {
 703                 case VSNORMAL:
 704                 case VSTRIMLEFT:
 705                 case VSTRIMLEFTMAX:
 706                 case VSTRIMRIGHT:
 707                 case VSTRIMRIGHTMAX:
 708                 case VSLENGTH:
 709                         error("%.*s: parameter not set", (int)(p - var - 1),
 710                             var);
 711                 }
 712         }
 713         if (set && subtype != VSPLUS) {
 714                 /* insert the value of the variable */
 715                 if (special) {
 716                         varvalue(var, varflags & VSQUOTE, subtype, flag);
 717                         if (subtype == VSLENGTH) {
 718                                 varlenb = expdest - stackblock() - startloc;
 719                                 varlen = varlenb;
 720                                 if (localeisutf8) {
 721                                         val = stackblock() + startloc;
 722                                         for (;val != expdest; val++)
 723                                                 if ((*val & 0xC0) == 0x80)
 724                                                         varlen--;
 725                                 }
 726                                 STADJUST(-varlenb, expdest);
 727                         }
 728                 } else {
 729                         char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
 730                                                                   : BASESYNTAX;
 731
 732                         if (subtype == VSLENGTH) {
 733                                 for (;*val; val++)
 734                                         if (!localeisutf8 ||
 735                                             (*val & 0xC0) != 0x80)
 736                                                 varlen++;
 737                         }
 738                         else {
 739                                 if (quotes)
 740                                         STPUTS_QUOTES(val, syntax, expdest);
 741                                 else
 742                                         STPUTS(val, expdest);
 743
 744                         }
 745                 }
 746         }
 747
 748         if (subtype == VSPLUS)
 749                 set = ! set;
 750
 751         easy = ((varflags & VSQUOTE) == 0 ||
 752                 (*var == '@' && shellparam.nparam != 1));
 753
 754
 755         switch (subtype) {
 756         case VSLENGTH:
 757                 expdest = cvtnum(varlen, expdest);
 758                 goto record;
 759
 760         case VSNORMAL:
 761                 if (!easy)
 762                         break;
 763 record:
 764                 recordregion(startloc, expdest - stackblock(),
 765                     varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
 766                     (*var == '@' || *var == '*')));
 767                 break;
 768
 769         case VSPLUS:
 770         case VSMINUS:
 771                 if (!set) {
 772                         argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
 773                             (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
 774                         break;
 775                 }
 776                 if (easy)
 777                         goto record;
 778                 break;
 779
 780         case VSTRIMLEFT:
 781         case VSTRIMLEFTMAX:
 782         case VSTRIMRIGHT:
 783         case VSTRIMRIGHTMAX:
 784                 if (!set)
 785                         break;
 786                 /*
 787                  * Terminate the string and start recording the pattern
 788                  * right after it
 789                  */
 790                 STPUTC('\0', expdest);
 791                 patloc = expdest - stackblock();
 792                 if (subevalvar(p, NULL, patloc, subtype,
 793                     startloc, varflags, quotes) == 0) {
 794                         int amount = (expdest - stackblock() - patloc) + 1;
 795                         STADJUST(-amount, expdest);
 796                 }
 797                 /* Remove any recorded regions beyond start of variable */
 798                 removerecordregions(startloc);
 799                 goto record;
 800
 801         case VSASSIGN:
 802         case VSQUESTION:
 803                 if (!set) {
 804                         if (subevalvar(p, var, 0, subtype, startloc, varflags,
 805                             quotes)) {
 806                                 varflags &= ~VSNUL;
 807                                 /*
 808                                  * Remove any recorded regions beyond
 809                                  * start of variable
 810                                  */
 811                                 removerecordregions(startloc);
 812                                 goto again;
 813                         }
 814                         break;
 815                 }
 816                 if (easy)
 817                         goto record;
 818                 break;
 819
 820         case VSERROR:
 821                 c = p - var - 1;
 822                 error("${%.*s%s}: Bad substitution", c, var,
 823                     (c > 0 && *p != CTLENDVAR) ? "..." : "");
 824
 825         default:
 826                 abort();
 827         }
 828         p[-1] = '=';    /* recover overwritten '=' */
 829
 830         if (subtype != VSNORMAL) {      /* skip to end of alternative */
 831                 int nesting = 1;
 832                 for (;;) {
 833                         if ((c = *p++) == CTLESC)
 834                                 p++;
 835                         else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
 836                                 if (set)
 837                                         argbackq = argbackq->next;
 838                         } else if (c == CTLVAR) {
 839                                 if ((*p++ & VSTYPE) != VSNORMAL)
 840                                         nesting++;
 841                         } else if (c == CTLENDVAR) {
 842                                 if (--nesting == 0)
 843                                         break;
 844                         }
 845                 }
 846         }
 847         return p;
 848 }
 849
 850
 851
 852 /*
 853  * Test whether a specialized variable is set.
 854  */
 855
 856 static int
 857 varisset(char *name, int nulok)
 858 {
 859
 860         if (*name == '!')
 861                 return backgndpidset();
 862         else if (*name == '@' || *name == '*') {
 863                 if (*shellparam.p == NULL)
 864                         return 0;
 865
 866                 if (nulok) {
 867                         char **av;
 868
 869                         for (av = shellparam.p; *av; av++)
 870                                 if (**av != '\0')
 871                                         return 1;
 872                         return 0;
 873                 }
 874         } else if (is_digit(*name)) {
 875                 char *ap;
 876                 int num = atoi(name);
 877
 878                 if (num > shellparam.nparam)
 879                         return 0;
 880
 881                 if (num == 0)
 882                         ap = arg0;
 883                 else
 884                         ap = shellparam.p[num - 1];
 885
 886                 if (nulok && (ap == NULL || *ap == '\0'))
 887                         return 0;
 888         }
 889         return 1;
 890 }
 891
 892 static void
 893 strtodest(const char *p, int flag, int subtype, int quoted)
 894 {
 895         if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH)
 896                 STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
 897         else
 898                 STPUTS(p, expdest);
 899 }
 900
 901 /*
 902  * Add the value of a specialized variable to the stack string.
 903  */
 904
 905 static void
 906 varvalue(char *name, int quoted, int subtype, int flag)
 907 {
 908         int num;
 909         char *p;
 910         int i;
 911         char sep;
 912         char **ap;
 913
 914         switch (*name) {
 915         case '$':
 916                 num = rootpid;
 917                 goto numvar;
 918         case '?':
 919                 num = oexitstatus;
 920                 goto numvar;
 921         case '#':
 922                 num = shellparam.nparam;
 923                 goto numvar;
 924         case '!':
 925                 num = backgndpidval();
 926 numvar:
 927                 expdest = cvtnum(num, expdest);
 928                 break;
 929         case '-':
 930                 for (i = 0 ; i < NOPTS ; i++) {
 931                         if (optlist[i].val)
 932                                 STPUTC(optlist[i].letter, expdest);
 933                 }
 934                 break;
 935         case '@':
 936                 if (flag & EXP_FULL && quoted) {
 937                         for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 938                                 strtodest(p, flag, subtype, quoted);
 939                                 if (*ap)
 940                                         STPUTC('\0', expdest);
 941                         }
 942                         break;
 943                 }
 944                 /* FALLTHROUGH */
 945         case '*':
 946                 if (ifsset())
 947                         sep = ifsval()[0];
 948                 else
 949                         sep = ' ';
 950                 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 951                         strtodest(p, flag, subtype, quoted);
 952                         if (!*ap)
 953                                 break;
 954                         if (sep || (flag & EXP_FULL && !quoted && **ap != '\0'))
 955                                 STPUTC(sep, expdest);
 956                 }
 957                 break;
 958         case '0':
 959                 p = arg0;
 960                 strtodest(p, flag, subtype, quoted);
 961                 break;
 962         default:
 963                 if (is_digit(*name)) {
 964                         num = atoi(name);
 965                         if (num > 0 && num <= shellparam.nparam) {
 966                                 p = shellparam.p[num - 1];
 967                                 strtodest(p, flag, subtype, quoted);
 968                         }
 969                 }
 970                 break;
 971         }
 972 }
 973
 974
 975
 976 /*
 977  * Record the fact that we have to scan this region of the
 978  * string for IFS characters.
 979  */
 980
 981 static void
 982 recordregion(int start, int end, int inquotes)
 983 {
 984         struct ifsregion *ifsp;
 985
 986         if (ifslastp == NULL) {
 987                 ifsp = &ifsfirst;
 988         } else {
 989                 if (ifslastp->endoff == start
 990                     && ifslastp->inquotes == inquotes) {
 991                         /* extend previous area */
 992                         ifslastp->endoff = end;
 993                         return;
 994                 }
 995                 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
 996                 ifslastp->next = ifsp;
 997         }
 998         ifslastp = ifsp;
 999         ifslastp->next = NULL;
1000         ifslastp->begoff = start;
1001         ifslastp->endoff = end;
1002         ifslastp->inquotes = inquotes;
1003 }
1004
1005
1006
1007 /*
1008  * Break the argument string into pieces based upon IFS and add the
1009  * strings to the argument list.  The regions of the string to be
1010  * searched for IFS characters have been stored by recordregion.
1011  * CTLESC characters are preserved but have little effect in this pass
1012  * other than escaping CTL* characters.  In particular, they do not escape
1013  * IFS characters: that should be done with the ifsregion mechanism.
1014  * CTLQUOTEMARK characters are used to preserve empty quoted strings.
1015  * This pass treats them as a regular character, making the string non-empty.
1016  * Later, they are removed along with the other CTL* characters.
1017  */
1018 static void
1019 ifsbreakup(char *string, struct arglist *arglist)
1020 {
1021         struct ifsregion *ifsp;
1022         struct strlist *sp;
1023         char *start;
1024         char *p;
1025         char *q;
1026         const char *ifs;
1027         const char *ifsspc;
1028         int had_param_ch = 0;
1029
1030         start = string;
1031
1032         if (ifslastp == NULL) {
1033                 /* Return entire argument, IFS doesn't apply to any of it */
1034                 sp = (struct strlist *)stalloc(sizeof *sp);
1035                 sp->text = start;
1036                 *arglist->lastp = sp;
1037                 arglist->lastp = &sp->next;
1038                 return;
1039         }
1040
1041         ifs = ifsset() ? ifsval() : " \t\n";
1042
1043         for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
1044                 p = string + ifsp->begoff;
1045                 while (p < string + ifsp->endoff) {
1046                         q = p;
1047                         if (*p == CTLESC)
1048                                 p++;
1049                         if (ifsp->inquotes) {
1050                                 /* Only NULs (should be from "$@") end args */
1051                                 had_param_ch = 1;
1052                                 if (*p != 0) {
1053                                         p++;
1054                                         continue;
1055                                 }
1056                                 ifsspc = NULL;
1057                         } else {
1058                                 if (!strchr(ifs, *p)) {
1059                                         had_param_ch = 1;
1060                                         p++;
1061                                         continue;
1062                                 }
1063                                 ifsspc = strchr(" \t\n", *p);
1064
1065                                 /* Ignore IFS whitespace at start */
1066                                 if (q == start && ifsspc != NULL) {
1067                                         p++;
1068                                         start = p;
1069                                         continue;
1070                                 }
1071                                 had_param_ch = 0;
1072                         }
1073
1074                         /* Save this argument... */
1075                         *q = '\0';
1076                         sp = (struct strlist *)stalloc(sizeof *sp);
1077                         sp->text = start;
1078                         *arglist->lastp = sp;
1079                         arglist->lastp = &sp->next;
1080                         p++;
1081
1082                         if (ifsspc != NULL) {
1083                                 /* Ignore further trailing IFS whitespace */
1084                                 for (; p < string + ifsp->endoff; p++) {
1085                                         q = p;
1086                                         if (*p == CTLESC)
1087                                                 p++;
1088                                         if (strchr(ifs, *p) == NULL) {
1089                                                 p = q;
1090                                                 break;
1091                                         }
1092                                         if (strchr(" \t\n", *p) == NULL) {
1093                                                 p++;
1094                                                 break;
1095                                         }
1096                                 }
1097                         }
1098                         start = p;
1099                 }
1100         }
1101
1102         /*
1103          * Save anything left as an argument.
1104          * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
1105          * generating 2 arguments, the second of which is empty.
1106          * Some recent clarification of the Posix spec say that it
1107          * should only generate one....
1108          */
1109         if (had_param_ch || *start != 0) {
1110                 sp = (struct strlist *)stalloc(sizeof *sp);
1111                 sp->text = start;
1112                 *arglist->lastp = sp;
1113                 arglist->lastp = &sp->next;
1114         }
1115 }
1116
1117
1118 static char expdir[PATH_MAX];
1119 #define expdir_end (expdir + sizeof(expdir))
1120
1121 /*
1122  * Perform pathname generation and remove control characters.
1123  * At this point, the only control characters should be CTLESC and CTLQUOTEMARK.
1124  * The results are stored in the list exparg.
1125  */
1126 static void
1127 expandmeta(struct strlist *str, int flag __unused)
1128 {
1129         char *p;
1130         struct strlist **savelastp;
1131         struct strlist *sp;
1132         char c;
1133         /* TODO - EXP_REDIR */
1134
1135         while (str) {
1136                 if (fflag)
1137                         goto nometa;
1138                 p = str->text;
1139                 for (;;) {                      /* fast check for meta chars */
1140                         if ((c = *p++) == '\0')
1141                                 goto nometa;
1142                         if (c == '*' || c == '?' || c == '[')
1143                                 break;
1144                 }
1145                 savelastp = exparg.lastp;
1146                 INTOFF;
1147                 expmeta(expdir, str->text);
1148                 INTON;
1149                 if (exparg.lastp == savelastp) {
1150                         /*
1151                          * no matches
1152                          */
1153 nometa:
1154                         *exparg.lastp = str;
1155                         rmescapes(str->text);
1156                         exparg.lastp = &str->next;
1157                 } else {
1158                         *exparg.lastp = NULL;
1159                         *savelastp = sp = expsort(*savelastp);
1160                         while (sp->next != NULL)
1161                                 sp = sp->next;
1162                         exparg.lastp = &sp->next;
1163                 }
1164                 str = str->next;
1165         }
1166 }
1167
1168
1169 /*
1170  * Do metacharacter (i.e. *, ?, [...]) expansion.
1171  */
1172
1173 static void
1174 expmeta(char *enddir, char *name)
1175 {
1176         char *p;
1177         char *q;
1178         char *start;
1179         char *endname;
1180         int metaflag;
1181         struct stat statb;
1182         DIR *dirp;
1183         struct dirent *dp;
1184         int atend;
1185         int matchdot;
1186         int esc;
1187
1188         metaflag = 0;
1189         start = name;
1190         for (p = name; esc = 0, *p; p += esc + 1) {
1191                 if (*p == '*' || *p == '?')
1192                         metaflag = 1;
1193                 else if (*p == '[') {
1194                         q = p + 1;
1195                         if (*q == '!' || *q == '^')
1196                                 q++;
1197                         for (;;) {
1198                                 while (*q == CTLQUOTEMARK)
1199                                         q++;
1200                                 if (*q == CTLESC)
1201                                         q++;
1202                                 if (*q == '/' || *q == '\0')
1203                                         break;
1204                                 if (*++q == ']') {
1205                                         metaflag = 1;
1206                                         break;
1207                                 }
1208                         }
1209                 } else if (*p == '\0')
1210                         break;
1211                 else if (*p == CTLQUOTEMARK)
1212                         continue;
1213                 else {
1214                         if (*p == CTLESC)
1215                                 esc++;
1216                         if (p[esc] == '/') {
1217                                 if (metaflag)
1218                                         break;
1219                                 start = p + esc + 1;
1220                         }
1221                 }
1222         }
1223         if (metaflag == 0) {    /* we've reached the end of the file name */
1224                 if (enddir != expdir)
1225                         metaflag++;
1226                 for (p = name ; ; p++) {
1227                         if (*p == CTLQUOTEMARK)
1228                                 continue;
1229                         if (*p == CTLESC)
1230                                 p++;
1231                         *enddir++ = *p;
1232                         if (*p == '\0')
1233                                 break;
1234                         if (enddir == expdir_end)
1235                                 return;
1236                 }
1237                 if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1238                         addfname(expdir);
1239                 return;
1240         }
1241         endname = p;
1242         if (start != name) {
1243                 p = name;
1244                 while (p < start) {
1245                         while (*p == CTLQUOTEMARK)
1246                                 p++;
1247                         if (*p == CTLESC)
1248                                 p++;
1249                         *enddir++ = *p++;
1250                         if (enddir == expdir_end)
1251                                 return;
1252                 }
1253         }
1254         if (enddir == expdir) {
1255                 p = __DECONST(char *, ".");
1256         } else if (enddir == expdir + 1 && *expdir == '/') {
1257                 p = __DECONST(char *, "/");
1258         } else {
1259                 p = expdir;
1260                 enddir[-1] = '\0';
1261         }
1262         if ((dirp = opendir(p)) == NULL)
1263                 return;
1264         if (enddir != expdir)
1265                 enddir[-1] = '/';
1266         if (*endname == 0) {
1267                 atend = 1;
1268         } else {
1269                 atend = 0;
1270                 *endname = '\0';
1271                 endname += esc + 1;
1272         }
1273         matchdot = 0;
1274         p = start;
1275         while (*p == CTLQUOTEMARK)
1276                 p++;
1277         if (*p == CTLESC)
1278                 p++;
1279         if (*p == '.')
1280                 matchdot++;
1281         while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1282                 if (dp->d_name[0] == '.' && ! matchdot)
1283                         continue;
1284                 if (patmatch(start, dp->d_name, 0)) {
1285                         if (enddir + dp->d_namlen + 1 > expdir_end)
1286                                 continue;
1287                         memcpy(enddir, dp->d_name, dp->d_namlen + 1);
1288                         if (atend)
1289                                 addfname(expdir);
1290                         else {
1291                                 if (enddir + dp->d_namlen + 2 > expdir_end)
1292                                         continue;
1293                                 enddir[dp->d_namlen] = '/';
1294                                 enddir[dp->d_namlen + 1] = '\0';
1295                                 expmeta(enddir + dp->d_namlen + 1, endname);
1296                         }
1297                 }
1298         }
1299         closedir(dirp);
1300         if (! atend)
1301                 endname[-esc - 1] = esc ? CTLESC : '/';
1302 }
1303
1304
1305 /*
1306  * Add a file name to the list.
1307  */
1308
1309 static void
1310 addfname(char *name)
1311 {
1312         char *p;
1313         struct strlist *sp;
1314
1315         p = stalloc(strlen(name) + 1);
1316         scopy(name, p);
1317         sp = (struct strlist *)stalloc(sizeof *sp);
1318         sp->text = p;
1319         *exparg.lastp = sp;
1320         exparg.lastp = &sp->next;
1321 }
1322
1323
1324 /*
1325  * Sort the results of file name expansion.  It calculates the number of
1326  * strings to sort and then calls msort (short for merge sort) to do the
1327  * work.
1328  */
1329
1330 static struct strlist *
1331 expsort(struct strlist *str)
1332 {
1333         int len;
1334         struct strlist *sp;
1335
1336         len = 0;
1337         for (sp = str ; sp ; sp = sp->next)
1338                 len++;
1339         return msort(str, len);
1340 }
1341
1342
1343 static struct strlist *
1344 msort(struct strlist *list, int len)
1345 {
1346         struct strlist *p, *q = NULL;
1347         struct strlist **lpp;
1348         int half;
1349         int n;
1350
1351         if (len <= 1)
1352                 return list;
1353         half = len >> 1;
1354         p = list;
1355         for (n = half ; --n >= 0 ; ) {
1356                 q = p;
1357                 p = p->next;
1358         }
1359         q->next = NULL;                 /* terminate first half of list */
1360         q = msort(list, half);          /* sort first half of list */
1361         p = msort(p, len - half);               /* sort second half */
1362         lpp = &list;
1363         for (;;) {
1364                 if (strcmp(p->text, q->text) < 0) {
1365                         *lpp = p;
1366                         lpp = &p->next;
1367                         if ((p = *lpp) == NULL) {
1368                                 *lpp = q;
1369                                 break;
1370                         }
1371                 } else {
1372                         *lpp = q;
1373                         lpp = &q->next;
1374                         if ((q = *lpp) == NULL) {
1375                                 *lpp = p;
1376                                 break;
1377                         }
1378                 }
1379         }
1380         return list;
1381 }
1382
1383
1384
1385 static wchar_t
1386 get_wc(const char **p)
1387 {
1388         wchar_t c;
1389         int chrlen;
1390
1391         chrlen = mbtowc(&c, *p, 4);
1392         if (chrlen == 0)
1393                 return 0;
1394         else if (chrlen == -1)
1395                 c = 0;
1396         else
1397                 *p += chrlen;
1398         return c;
1399 }
1400
1401
1402 /*
1403  * Returns true if the pattern matches the string.
1404  */
1405
1406 int
1407 patmatch(const char *pattern, const char *string, int squoted)
1408 {
1409         const char *p, *q;
1410         char c;
1411         wchar_t wc, wc2;
1412
1413         p = pattern;
1414         q = string;
1415         for (;;) {
1416                 switch (c = *p++) {
1417                 case '\0':
1418                         goto breakloop;
1419                 case CTLESC:
1420                         if (squoted && *q == CTLESC)
1421                                 q++;
1422                         if (*q++ != *p++)
1423                                 return 0;
1424                         break;
1425                 case CTLQUOTEMARK:
1426                         continue;
1427                 case '?':
1428                         if (squoted && *q == CTLESC)
1429                                 q++;
1430                         if (localeisutf8)
1431                                 wc = get_wc(&q);
1432                         else
1433                                 wc = (unsigned char)*q++;
1434                         if (wc == '\0')
1435                                 return 0;
1436                         break;
1437                 case '*':
1438                         c = *p;
1439                         while (c == CTLQUOTEMARK || c == '*')
1440                                 c = *++p;
1441                         if (c != CTLESC &&  c != CTLQUOTEMARK &&
1442                             c != '?' && c != '*' && c != '[') {
1443                                 while (*q != c) {
1444                                         if (squoted && *q == CTLESC &&
1445                                             q[1] == c)
1446                                                 break;
1447                                         if (*q == '\0')
1448                                                 return 0;
1449                                         if (squoted && *q == CTLESC)
1450                                                 q++;
1451                                         q++;
1452                                 }
1453                         }
1454                         do {
1455                                 if (patmatch(p, q, squoted))
1456                                         return 1;
1457                                 if (squoted && *q == CTLESC)
1458                                         q++;
1459                         } while (*q++ != '\0');
1460                         return 0;
1461                 case '[': {
1462                         const char *endp;
1463                         int invert, found;
1464                         wchar_t chr;
1465
1466                         endp = p;
1467                         if (*endp == '!' || *endp == '^')
1468                                 endp++;
1469                         for (;;) {
1470                                 while (*endp == CTLQUOTEMARK)
1471                                         endp++;
1472                                 if (*endp == '\0')
1473                                         goto dft;               /* no matching ] */
1474                                 if (*endp == CTLESC)
1475                                         endp++;
1476                                 if (*++endp == ']')
1477                                         break;
1478                         }
1479                         invert = 0;
1480                         if (*p == '!' || *p == '^') {
1481                                 invert++;
1482                                 p++;
1483                         }
1484                         found = 0;
1485                         if (squoted && *q == CTLESC)
1486                                 q++;
1487                         if (localeisutf8)
1488                                 chr = get_wc(&q);
1489                         else
1490                                 chr = (unsigned char)*q++;
1491                         if (chr == '\0')
1492                                 return 0;
1493                         c = *p++;
1494                         do {
1495                                 if (c == CTLQUOTEMARK)
1496                                         continue;
1497                                 if (c == CTLESC)
1498                                         c = *p++;
1499                                 if (localeisutf8 && c & 0x80) {
1500                                         p--;
1501                                         wc = get_wc(&p);
1502                                         if (wc == 0) /* bad utf-8 */
1503                                                 return 0;
1504                                 } else
1505                                         wc = (unsigned char)c;
1506                                 if (*p == '-' && p[1] != ']') {
1507                                         p++;
1508                                         while (*p == CTLQUOTEMARK)
1509                                                 p++;
1510                                         if (*p == CTLESC)
1511                                                 p++;
1512                                         if (localeisutf8) {
1513                                                 wc2 = get_wc(&p);
1514                                                 if (wc2 == 0) /* bad utf-8 */
1515                                                         return 0;
1516                                         } else
1517                                                 wc2 = (unsigned char)*p++;
1518                                         if (   collate_range_cmp(chr, wc) >= 0
1519                                             && collate_range_cmp(chr, wc2) <= 0
1520                                            )
1521                                                 found = 1;
1522                                 } else {
1523                                         if (chr == wc)
1524                                                 found = 1;
1525                                 }
1526                         } while ((c = *p++) != ']');
1527                         if (found == invert)
1528                                 return 0;
1529                         break;
1530                 }
1531 dft:            default:
1532                         if (squoted && *q == CTLESC)
1533                                 q++;
1534                         if (*q++ != c)
1535                                 return 0;
1536                         break;
1537                 }
1538         }
1539 breakloop:
1540         if (*q != '\0')
1541                 return 0;
1542         return 1;
1543 }
1544
1545
1546
1547 /*
1548  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1549  */
1550
1551 void
1552 rmescapes(char *str)
1553 {
1554         char *p, *q;
1555
1556         p = str;
1557         while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1558                 if (*p++ == '\0')
1559                         return;
1560         }
1561         q = p;
1562         while (*p) {
1563                 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1564                         p++;
1565                         continue;
1566                 }
1567                 if (*p == CTLESC)
1568                         p++;
1569                 *q++ = *p++;
1570         }
1571         *q = '\0';
1572 }
1573
1574
1575
1576 /*
1577  * See if a pattern matches in a case statement.
1578  */
1579
1580 int
1581 casematch(union node *pattern, const char *val)
1582 {
1583         struct stackmark smark;
1584         int result;
1585         char *p;
1586
1587         setstackmark(&smark);
1588         argbackq = pattern->narg.backquote;
1589         STARTSTACKSTR(expdest);
1590         ifslastp = NULL;
1591         argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1592         STPUTC('\0', expdest);
1593         p = grabstackstr(expdest);
1594         result = patmatch(p, val, 0);
1595         popstackmark(&smark);
1596         return result;
1597 }
1598
1599 /*
1600  * Our own itoa().
1601  */
1602
1603 static char *
1604 cvtnum(int num, char *buf)
1605 {
1606         char temp[32];
1607         int neg = num < 0;
1608         char *p = temp + 31;
1609
1610         temp[31] = '\0';
1611
1612         do {
1613                 *--p = num % 10 + '0';
1614         } while ((num /= 10) != 0);
1615
1616         if (neg)
1617                 *--p = '-';
1618
1619         STPUTS(p, buf);
1620         return buf;
1621 }
1622
1623 /*
1624  * Do most of the work for wordexp(3).
1625  */
1626
1627 int
1628 wordexpcmd(int argc, char **argv)
1629 {
1630         size_t len;
1631         int i;
1632
1633         out1fmt("%08x", argc - 1);
1634         for (i = 1, len = 0; i < argc; i++)
1635                 len += strlen(argv[i]);
1636         out1fmt("%08x", (int)len);
1637         for (i = 1; i < argc; i++)
1638                 outbin(argv[i], strlen(argv[i]) + 1, out1);
1639         return (0);
1640 }