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