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  * Copyright (c) 2010-2015
   7  *      Jilles Tjoelker <jilles@stack.nl>.  All rights reserved.
   8  *
   9  * This code is derived from software contributed to Berkeley by
  10  * Kenneth Almquist.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  */
  36
  37 #ifndef lint
  38 #if 0
  39 static char sccsid[] = "@(#)expand.c    8.5 (Berkeley) 5/15/95";
  40 #endif
  41 #endif /* not lint */
  42 #include <sys/cdefs.h>
  43 __FBSDID("$FreeBSD: head/bin/sh/expand.c 341164 2018-11-28 20:03:53Z jilles $");
  44
  45 #include <sys/types.h>
  46 #include <sys/time.h>
  47 #include <sys/stat.h>
  48 #include <dirent.h>
  49 #include <errno.h>
  50 #include <inttypes.h>
  51 #include <limits.h>
  52 #include <pwd.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <string.h>
  56 #include <unistd.h>
  57 #include <wchar.h>
  58 #include <wctype.h>
  59
  60 /*
  61  * Routines to expand arguments to commands.  We have to deal with
  62  * backquotes, shell variables, and file metacharacters.
  63  */
  64
  65 #include "shell.h"
  66 #include "main.h"
  67 #include "nodes.h"
  68 #include "eval.h"
  69 #include "expand.h"
  70 #include "syntax.h"
  71 #include "parser.h"
  72 #include "jobs.h"
  73 #include "options.h"
  74 #include "var.h"
  75 #include "input.h"
  76 #include "output.h"
  77 #include "memalloc.h"
  78 #include "error.h"
  79 #include "mystring.h"
  80 #include "arith.h"
  81 #include "show.h"
  82 #include "builtins.h"
  83
  84 enum wordstate { WORD_IDLE, WORD_WS_DELIMITED, WORD_QUOTEMARK };
  85
  86 struct worddest {
  87         struct arglist *list;
  88         enum wordstate state;
  89 };
  90
  91 static char *expdest;                   /* output of current string */
  92
  93 static const char *argstr(const char *, struct nodelist **restrict, int,
  94     struct worddest *);
  95 static const char *exptilde(const char *, int);
  96 static const char *expari(const char *, struct nodelist **restrict, int,
  97     struct worddest *);
  98 static void expbackq(union node *, int, int, struct worddest *);
  99 static const char *subevalvar_trim(const char *, struct nodelist **restrict,
 100     int, int, int);
 101 static const char *subevalvar_misc(const char *, struct nodelist **restrict,
 102     const char *, int, int, int);
 103 static const char *evalvar(const char *, struct nodelist **restrict, int,
 104     struct worddest *);
 105 static int varisset(const char *, int);
 106 static void strtodest(const char *, int, int, int, struct worddest *);
 107 static void reprocess(int, int, int, int, struct worddest *);
 108 static void varvalue(const char *, int, int, int, struct worddest *);
 109 static void expandmeta(char *, struct arglist *);
 110 static void expmeta(char *, char *, struct arglist *);
 111 static int expsortcmp(const void *, const void *);
 112 static int patmatch(const char *, const char *);
 113 static void cvtnum(int, char *);
 114 static int collate_range_cmp(wchar_t, wchar_t);
 115
 116 void
 117 emptyarglist(struct arglist *list)
 118 {
 119
 120         list->args = list->smallarg;
 121         list->count = 0;
 122         list->capacity = sizeof(list->smallarg) / sizeof(list->smallarg[0]);
 123 }
 124
 125 void
 126 appendarglist(struct arglist *list, char *str)
 127 {
 128         char **newargs;
 129         int newcapacity;
 130
 131         if (list->count >= list->capacity) {
 132                 newcapacity = list->capacity * 2;
 133                 if (newcapacity < 16)
 134                         newcapacity = 16;
 135                 if (newcapacity > INT_MAX / (int)sizeof(newargs[0]))
 136                         error("Too many entries in arglist");
 137                 newargs = stalloc(newcapacity * sizeof(newargs[0]));
 138                 memcpy(newargs, list->args, list->count * sizeof(newargs[0]));
 139                 list->args = newargs;
 140                 list->capacity = newcapacity;
 141         }
 142         list->args[list->count++] = str;
 143 }
 144
 145 static int
 146 collate_range_cmp(wchar_t c1, wchar_t c2)
 147 {
 148         wchar_t s1[2], s2[2];
 149
 150         s1[0] = c1;
 151         s1[1] = L'\0';
 152         s2[0] = c2;
 153         s2[1] = L'\0';
 154         return (wcscoll(s1, s2));
 155 }
 156
 157 static char *
 158 stputs_quotes(const char *data, const char *syntax, char *p)
 159 {
 160         while (*data) {
 161                 CHECKSTRSPACE(2, p);
 162                 if (syntax[(int)*data] == CCTL)
 163                         USTPUTC(CTLESC, p);
 164                 USTPUTC(*data++, p);
 165         }
 166         return (p);
 167 }
 168 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
 169
 170 static char *
 171 nextword(char c, int flag, char *p, struct worddest *dst)
 172 {
 173         int is_ws;
 174
 175         is_ws = c == '\t' || c == '\n' || c == ' ';
 176         if (p != stackblock() || (is_ws ? dst->state == WORD_QUOTEMARK :
 177             dst->state != WORD_WS_DELIMITED) || c == '\0') {
 178                 STPUTC('\0', p);
 179                 if (flag & EXP_GLOB)
 180                         expandmeta(grabstackstr(p), dst->list);
 181                 else
 182                         appendarglist(dst->list, grabstackstr(p));
 183                 dst->state = is_ws ? WORD_WS_DELIMITED : WORD_IDLE;
 184         } else if (!is_ws && dst->state == WORD_WS_DELIMITED)
 185                 dst->state = WORD_IDLE;
 186         /* Reserve space while the stack string is empty. */
 187         appendarglist(dst->list, NULL);
 188         dst->list->count--;
 189         STARTSTACKSTR(p);
 190         return p;
 191 }
 192 #define NEXTWORD(c, flag, p, dstlist) p = nextword(c, flag, p, dstlist)
 193
 194 static char *
 195 stputs_split(const char *data, const char *syntax, int flag, char *p,
 196     struct worddest *dst)
 197 {
 198         const char *ifs;
 199         char c;
 200
 201         ifs = ifsset() ? ifsval() : " \t\n";
 202         while (*data) {
 203                 CHECKSTRSPACE(2, p);
 204                 c = *data++;
 205                 if (strchr(ifs, c) != NULL) {
 206                         NEXTWORD(c, flag, p, dst);
 207                         continue;
 208                 }
 209                 if (flag & EXP_GLOB && syntax[(int)c] == CCTL)
 210                         USTPUTC(CTLESC, p);
 211                 USTPUTC(c, p);
 212         }
 213         return (p);
 214 }
 215 #define STPUTS_SPLIT(data, syntax, flag, p, dst) p = stputs_split((data), syntax, flag, p, dst)
 216
 217 /*
 218  * Perform expansions on an argument, placing the resulting list of arguments
 219  * in arglist.  Parameter expansion, command substitution and arithmetic
 220  * expansion are always performed; additional expansions can be requested
 221  * via flag (EXP_*).
 222  * The result is left in the stack string.
 223  * When arglist is NULL, perform here document expansion.
 224  *
 225  * When doing something that may cause this to be re-entered, make sure
 226  * the stack string is empty via grabstackstr() and do not assume expdest
 227  * remains valid.
 228  */
 229 void
 230 expandarg(union node *arg, struct arglist *arglist, int flag)
 231 {
 232         struct worddest exparg;
 233         struct nodelist *argbackq;
 234
 235         if (fflag)
 236                 flag &= ~EXP_GLOB;
 237         argbackq = arg->narg.backquote;
 238         exparg.list = arglist;
 239         exparg.state = WORD_IDLE;
 240         STARTSTACKSTR(expdest);
 241         argstr(arg->narg.text, &argbackq, flag, &exparg);
 242         if (arglist == NULL) {
 243                 STACKSTRNUL(expdest);
 244                 return;                 /* here document expanded */
 245         }
 246         if ((flag & EXP_SPLIT) == 0 || expdest != stackblock() ||
 247             exparg.state == WORD_QUOTEMARK) {
 248                 STPUTC('\0', expdest);
 249                 if (flag & EXP_SPLIT) {
 250                         if (flag & EXP_GLOB)
 251                                 expandmeta(grabstackstr(expdest), exparg.list);
 252                         else
 253                                 appendarglist(exparg.list, grabstackstr(expdest));
 254                 }
 255         }
 256         if ((flag & EXP_SPLIT) == 0)
 257                 appendarglist(arglist, grabstackstr(expdest));
 258 }
 259
 260
 261
 262 /*
 263  * Perform parameter expansion, command substitution and arithmetic
 264  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
 265  * Processing ends at a CTLENDVAR or CTLENDARI character as well as '\0'.
 266  * This is used to expand word in ${var+word} etc.
 267  * If EXP_GLOB or EXP_CASE are set, keep and/or generate CTLESC
 268  * characters to allow for further processing.
 269  *
 270  * If EXP_SPLIT is set, dst receives any complete words produced.
 271  */
 272 static const char *
 273 argstr(const char *p, struct nodelist **restrict argbackq, int flag,
 274     struct worddest *dst)
 275 {
 276         char c;
 277         int quotes = flag & (EXP_GLOB | EXP_CASE);      /* do CTLESC */
 278         int firsteq = 1;
 279         int split_lit;
 280         int lit_quoted;
 281
 282         split_lit = flag & EXP_SPLIT_LIT;
 283         lit_quoted = flag & EXP_LIT_QUOTED;
 284         flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
 285         if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
 286                 p = exptilde(p, flag);
 287         for (;;) {
 288                 CHECKSTRSPACE(2, expdest);
 289                 switch (c = *p++) {
 290                 case '\0':
 291                         return (p - 1);
 292                 case CTLENDVAR:
 293                 case CTLENDARI:
 294                         return (p);
 295                 case CTLQUOTEMARK:
 296                         lit_quoted = 1;
 297                         /* "$@" syntax adherence hack */
 298                         if (p[0] == CTLVAR && (p[1] & VSQUOTE) != 0 &&
 299                             p[2] == '@' && p[3] == '=')
 300                                 break;
 301                         if ((flag & EXP_SPLIT) != 0 && expdest == stackblock())
 302                                 dst->state = WORD_QUOTEMARK;
 303                         break;
 304                 case CTLQUOTEEND:
 305                         lit_quoted = 0;
 306                         break;
 307                 case CTLESC:
 308                         c = *p++;
 309                         if (split_lit && !lit_quoted &&
 310                             strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
 311                                 NEXTWORD(c, flag, expdest, dst);
 312                                 break;
 313                         }
 314                         if (quotes)
 315                                 USTPUTC(CTLESC, expdest);
 316                         USTPUTC(c, expdest);
 317                         break;
 318                 case CTLVAR:
 319                         p = evalvar(p, argbackq, flag, dst);
 320                         break;
 321                 case CTLBACKQ:
 322                 case CTLBACKQ|CTLQUOTE:
 323                         expbackq((*argbackq)->n, c & CTLQUOTE, flag, dst);
 324                         *argbackq = (*argbackq)->next;
 325                         break;
 326                 case CTLARI:
 327                         p = expari(p, argbackq, flag, dst);
 328                         break;
 329                 case ':':
 330                 case '=':
 331                         /*
 332                          * sort of a hack - expand tildes in variable
 333                          * assignments (after the first '=' and after ':'s).
 334                          */
 335                         if (split_lit && !lit_quoted &&
 336                             strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
 337                                 NEXTWORD(c, flag, expdest, dst);
 338                                 break;
 339                         }
 340                         USTPUTC(c, expdest);
 341                         if (flag & EXP_VARTILDE && *p == '~' &&
 342                             (c != '=' || firsteq)) {
 343                                 if (c == '=')
 344                                         firsteq = 0;
 345                                 p = exptilde(p, flag);
 346                         }
 347                         break;
 348                 default:
 349                         if (split_lit && !lit_quoted &&
 350                             strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
 351                                 NEXTWORD(c, flag, expdest, dst);
 352                                 break;
 353                         }
 354                         USTPUTC(c, expdest);
 355                 }
 356         }
 357 }
 358
 359 /*
 360  * Perform tilde expansion, placing the result in the stack string and
 361  * returning the next position in the input string to process.
 362  */
 363 static const char *
 364 exptilde(const char *p, int flag)
 365 {
 366         char c;
 367         const char *startp = p;
 368         const char *user;
 369         struct passwd *pw;
 370         char *home;
 371         int len;
 372
 373         for (;;) {
 374                 c = *p;
 375                 switch(c) {
 376                 case CTLESC: /* This means CTL* are always considered quoted. */
 377                 case CTLVAR:
 378                 case CTLBACKQ:
 379                 case CTLBACKQ | CTLQUOTE:
 380                 case CTLARI:
 381                 case CTLENDARI:
 382                 case CTLQUOTEMARK:
 383                         return (startp);
 384                 case ':':
 385                         if ((flag & EXP_VARTILDE) == 0)
 386                                 break;
 387                         /* FALLTHROUGH */
 388                 case '\0':
 389                 case '/':
 390                 case CTLENDVAR:
 391                         len = p - startp - 1;
 392                         STPUTBIN(startp + 1, len, expdest);
 393                         STACKSTRNUL(expdest);
 394                         user = expdest - len;
 395                         if (*user == '\0') {
 396                                 home = lookupvar("HOME");
 397                         } else {
 398                                 pw = getpwnam(user);
 399                                 home = pw != NULL ? pw->pw_dir : NULL;
 400                         }
 401                         STADJUST(-len, expdest);
 402                         if (home == NULL || *home == '\0')
 403                                 return (startp);
 404                         strtodest(home, flag, VSNORMAL, 1, NULL);
 405                         return (p);
 406                 }
 407                 p++;
 408         }
 409 }
 410
 411
 412 /*
 413  * Expand arithmetic expression.
 414  */
 415 static const char *
 416 expari(const char *p, struct nodelist **restrict argbackq, int flag,
 417     struct worddest *dst)
 418 {
 419         char *q, *start;
 420         arith_t result;
 421         int begoff;
 422         int quoted;
 423         int adj;
 424
 425         quoted = *p++ == '"';
 426         begoff = expdest - stackblock();
 427         p = argstr(p, argbackq, 0, NULL);
 428         STPUTC('\0', expdest);
 429         start = stackblock() + begoff;
 430
 431         q = grabstackstr(expdest);
 432         result = arith(start);
 433         ungrabstackstr(q, expdest);
 434
 435         start = stackblock() + begoff;
 436         adj = start - expdest;
 437         STADJUST(adj, expdest);
 438
 439         CHECKSTRSPACE((int)(DIGITS(result) + 1), expdest);
 440         fmtstr(expdest, DIGITS(result), ARITH_FORMAT_STR, result);
 441         adj = strlen(expdest);
 442         STADJUST(adj, expdest);
 443         /*
 444          * If this is quoted, a '-' must not indicate a range in [...].
 445          * If this is not quoted, splitting may occur.
 446          */
 447         if (quoted ?
 448             result < 0 && begoff > 1 && flag & (EXP_GLOB | EXP_CASE) :
 449             flag & EXP_SPLIT)
 450                 reprocess(expdest - adj - stackblock(), flag, VSNORMAL, quoted,
 451                     dst);
 452         return p;
 453 }
 454
 455
 456 /*
 457  * Perform command substitution.
 458  */
 459 static void
 460 expbackq(union node *cmd, int quoted, int flag, struct worddest *dst)
 461 {
 462         struct backcmd in;
 463         int i;
 464         char buf[128];
 465         char *p;
 466         char *dest = expdest;
 467         char lastc;
 468         char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
 469         int quotes = flag & (EXP_GLOB | EXP_CASE);
 470         size_t nnl;
 471         const char *ifs;
 472         int startloc;
 473
 474         INTOFF;
 475         p = grabstackstr(dest);
 476         evalbackcmd(cmd, &in);
 477         ungrabstackstr(p, dest);
 478
 479         p = in.buf;
 480         startloc = dest - stackblock();
 481         nnl = 0;
 482         if (!quoted && flag & EXP_SPLIT)
 483                 ifs = ifsset() ? ifsval() : " \t\n";
 484         else
 485                 ifs = "";
 486         /* Remove trailing newlines */
 487         for (;;) {
 488                 if (--in.nleft < 0) {
 489                         if (in.fd < 0)
 490                                 break;
 491                         while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR)
 492                                 ;
 493                         TRACE(("expbackq: read returns %d\n", i));
 494                         if (i <= 0)
 495                                 break;
 496                         p = buf;
 497                         in.nleft = i - 1;
 498                 }
 499                 lastc = *p++;
 500                 if (lastc == '\0')
 501                         continue;
 502                 if (nnl > 0 && lastc != '\n') {
 503                         NEXTWORD('\n', flag, dest, dst);
 504                         nnl = 0;
 505                 }
 506                 if (strchr(ifs, lastc) != NULL) {
 507                         if (lastc == '\n')
 508                                 nnl++;
 509                         else
 510                                 NEXTWORD(lastc, flag, dest, dst);
 511                 } else {
 512                         CHECKSTRSPACE(2, dest);
 513                         if (quotes && syntax[(int)lastc] == CCTL)
 514                                 USTPUTC(CTLESC, dest);
 515                         USTPUTC(lastc, dest);
 516                 }
 517         }
 518         while (dest > stackblock() + startloc && STTOPC(dest) == '\n')
 519                 STUNPUTC(dest);
 520
 521         if (in.fd >= 0)
 522                 close(in.fd);
 523         if (in.buf)
 524                 ckfree(in.buf);
 525         if (in.jp) {
 526                 p = grabstackstr(dest);
 527                 exitstatus = waitforjob(in.jp, (int *)NULL);
 528                 ungrabstackstr(p, dest);
 529         }
 530         TRACE(("expbackq: done\n"));
 531         expdest = dest;
 532         INTON;
 533 }
 534
 535
 536
 537 static void
 538 recordleft(const char *str, const char *loc, char *startp)
 539 {
 540         int amount;
 541
 542         amount = ((str - 1) - (loc - startp)) - expdest;
 543         STADJUST(amount, expdest);
 544         while (loc != str - 1)
 545                 *startp++ = *loc++;
 546 }
 547
 548 static const char *
 549 subevalvar_trim(const char *p, struct nodelist **restrict argbackq, int strloc,
 550     int subtype, int startloc)
 551 {
 552         char *startp;
 553         char *loc = NULL;
 554         char *str;
 555         int c = 0;
 556         int amount;
 557
 558         p = argstr(p, argbackq, EXP_CASE | EXP_TILDE, NULL);
 559         STACKSTRNUL(expdest);
 560         startp = stackblock() + startloc;
 561         str = stackblock() + strloc;
 562
 563         switch (subtype) {
 564         case VSTRIMLEFT:
 565                 for (loc = startp; loc < str; loc++) {
 566                         c = *loc;
 567                         *loc = '\0';
 568                         if (patmatch(str, startp)) {
 569                                 *loc = c;
 570                                 recordleft(str, loc, startp);
 571                                 return p;
 572                         }
 573                         *loc = c;
 574                 }
 575                 break;
 576
 577         case VSTRIMLEFTMAX:
 578                 for (loc = str - 1; loc >= startp;) {
 579                         c = *loc;
 580                         *loc = '\0';
 581                         if (patmatch(str, startp)) {
 582                                 *loc = c;
 583                                 recordleft(str, loc, startp);
 584                                 return p;
 585                         }
 586                         *loc = c;
 587                         loc--;
 588                 }
 589                 break;
 590
 591         case VSTRIMRIGHT:
 592                 for (loc = str - 1; loc >= startp;) {
 593                         if (patmatch(str, loc)) {
 594                                 amount = loc - expdest;
 595                                 STADJUST(amount, expdest);
 596                                 return p;
 597                         }
 598                         loc--;
 599                 }
 600                 break;
 601
 602         case VSTRIMRIGHTMAX:
 603                 for (loc = startp; loc < str - 1; loc++) {
 604                         if (patmatch(str, loc)) {
 605                                 amount = loc - expdest;
 606                                 STADJUST(amount, expdest);
 607                                 return p;
 608                         }
 609                 }
 610                 break;
 611
 612
 613         default:
 614                 abort();
 615         }
 616         amount = (expdest - stackblock() - strloc) + 1;
 617         STADJUST(-amount, expdest);
 618         return p;
 619 }
 620
 621
 622 static const char *
 623 subevalvar_misc(const char *p, struct nodelist **restrict argbackq,
 624     const char *var, int subtype, int startloc, int varflags)
 625 {
 626         const char *end;
 627         char *startp;
 628         int amount;
 629
 630         end = argstr(p, argbackq, EXP_TILDE, NULL);
 631         STACKSTRNUL(expdest);
 632         startp = stackblock() + startloc;
 633
 634         switch (subtype) {
 635         case VSASSIGN:
 636                 setvar(var, startp, 0);
 637                 amount = startp - expdest;
 638                 STADJUST(amount, expdest);
 639                 return end;
 640
 641         case VSQUESTION:
 642                 if (*p != CTLENDVAR) {
 643                         outfmt(out2, "%s\n", startp);
 644                         error((char *)NULL);
 645                 }
 646                 error("%.*s: parameter %snot set", (int)(p - var - 1),
 647                       var, (varflags & VSNUL) ? "null or " : "");
 648
 649         default:
 650                 abort();
 651         }
 652 }
 653
 654
 655 /*
 656  * Expand a variable, and return a pointer to the next character in the
 657  * input string.
 658  */
 659
 660 static const char *
 661 evalvar(const char *p, struct nodelist **restrict argbackq, int flag,
 662     struct worddest *dst)
 663 {
 664         int subtype;
 665         int varflags;
 666         const char *var;
 667         const char *val;
 668         int patloc;
 669         int c;
 670         int set;
 671         int special;
 672         int startloc;
 673         int varlen;
 674         int varlenb;
 675         char buf[21];
 676
 677         varflags = (unsigned char)*p++;
 678         subtype = varflags & VSTYPE;
 679         var = p;
 680         special = 0;
 681         if (! is_name(*p))
 682                 special = 1;
 683         p = strchr(p, '=') + 1;
 684         if (varflags & VSLINENO) {
 685                 set = 1;
 686                 special = 1;
 687                 val = NULL;
 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                         if (varflags & VSLINENO) {
 717                                 if (p - var > (ptrdiff_t)sizeof(buf))
 718                                         abort();
 719                                 memcpy(buf, var, p - var - 1);
 720                                 buf[p - var - 1] = '\0';
 721                                 strtodest(buf, flag, subtype,
 722                                     varflags & VSQUOTE, dst);
 723                         } else
 724                                 varvalue(var, varflags & VSQUOTE, subtype, flag,
 725                                     dst);
 726                         if (subtype == VSLENGTH) {
 727                                 varlenb = expdest - stackblock() - startloc;
 728                                 varlen = varlenb;
 729                                 if (localeisutf8) {
 730                                         val = stackblock() + startloc;
 731                                         for (;val != expdest; val++)
 732                                                 if ((*val & 0xC0) == 0x80)
 733                                                         varlen--;
 734                                 }
 735                                 STADJUST(-varlenb, expdest);
 736                         }
 737                 } else {
 738                         if (subtype == VSLENGTH) {
 739                                 for (;*val; val++)
 740                                         if (!localeisutf8 ||
 741                                             (*val & 0xC0) != 0x80)
 742                                                 varlen++;
 743                         }
 744                         else
 745                                 strtodest(val, flag, subtype,
 746                                     varflags & VSQUOTE, dst);
 747                 }
 748         }
 749
 750         if (subtype == VSPLUS)
 751                 set = ! set;
 752
 753         switch (subtype) {
 754         case VSLENGTH:
 755                 cvtnum(varlen, buf);
 756                 strtodest(buf, flag, VSNORMAL, varflags & VSQUOTE, dst);
 757                 break;
 758
 759         case VSNORMAL:
 760                 return p;
 761
 762         case VSPLUS:
 763         case VSMINUS:
 764                 if (!set) {
 765                         return argstr(p, argbackq,
 766                             flag | (flag & EXP_SPLIT ? EXP_SPLIT_LIT : 0) |
 767                             (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0), dst);
 768                 }
 769                 break;
 770
 771         case VSTRIMLEFT:
 772         case VSTRIMLEFTMAX:
 773         case VSTRIMRIGHT:
 774         case VSTRIMRIGHTMAX:
 775                 if (!set)
 776                         break;
 777                 /*
 778                  * Terminate the string and start recording the pattern
 779                  * right after it
 780                  */
 781                 STPUTC('\0', expdest);
 782                 patloc = expdest - stackblock();
 783                 p = subevalvar_trim(p, argbackq, patloc, subtype, startloc);
 784                 reprocess(startloc, flag, VSNORMAL, varflags & VSQUOTE, dst);
 785                 if (flag & EXP_SPLIT && *var == '@' && varflags & VSQUOTE)
 786                         dst->state = WORD_QUOTEMARK;
 787                 return p;
 788
 789         case VSASSIGN:
 790         case VSQUESTION:
 791                 if (!set) {
 792                         p = subevalvar_misc(p, argbackq, var, subtype,
 793                             startloc, varflags);
 794                         /* assert(subtype == VSASSIGN); */
 795                         val = lookupvar(var);
 796                         strtodest(val, flag, subtype, varflags & VSQUOTE, dst);
 797                         return p;
 798                 }
 799                 break;
 800
 801         case VSERROR:
 802                 c = p - var - 1;
 803                 error("${%.*s%s}: Bad substitution", c, var,
 804                     (c > 0 && *p != CTLENDVAR) ? "..." : "");
 805
 806         default:
 807                 abort();
 808         }
 809
 810         {       /* skip to end of alternative */
 811                 int nesting = 1;
 812                 for (;;) {
 813                         if ((c = *p++) == CTLESC)
 814                                 p++;
 815                         else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE))
 816                                 *argbackq = (*argbackq)->next;
 817                         else if (c == CTLVAR) {
 818                                 if ((*p++ & VSTYPE) != VSNORMAL)
 819                                         nesting++;
 820                         } else if (c == CTLENDVAR) {
 821                                 if (--nesting == 0)
 822                                         break;
 823                         }
 824                 }
 825         }
 826         return p;
 827 }
 828
 829
 830
 831 /*
 832  * Test whether a special or positional parameter is set.
 833  */
 834
 835 static int
 836 varisset(const char *name, int nulok)
 837 {
 838
 839         if (*name == '!')
 840                 return backgndpidset();
 841         else if (*name == '@' || *name == '*') {
 842                 if (*shellparam.p == NULL)
 843                         return 0;
 844
 845                 if (nulok) {
 846                         char **av;
 847
 848                         for (av = shellparam.p; *av; av++)
 849                                 if (**av != '\0')
 850                                         return 1;
 851                         return 0;
 852                 }
 853         } else if (is_digit(*name)) {
 854                 char *ap;
 855                 long num;
 856
 857                 errno = 0;
 858                 num = strtol(name, NULL, 10);
 859                 if (errno != 0 || num > shellparam.nparam)
 860                         return 0;
 861
 862                 if (num == 0)
 863                         ap = arg0;
 864                 else
 865                         ap = shellparam.p[num - 1];
 866
 867                 if (nulok && (ap == NULL || *ap == '\0'))
 868                         return 0;
 869         }
 870         return 1;
 871 }
 872
 873 static void
 874 strtodest(const char *p, int flag, int subtype, int quoted,
 875     struct worddest *dst)
 876 {
 877         if (subtype == VSLENGTH || subtype == VSTRIMLEFT ||
 878             subtype == VSTRIMLEFTMAX || subtype == VSTRIMRIGHT ||
 879             subtype == VSTRIMRIGHTMAX)
 880                 STPUTS(p, expdest);
 881         else if (flag & EXP_SPLIT && !quoted && dst != NULL)
 882                 STPUTS_SPLIT(p, BASESYNTAX, flag, expdest, dst);
 883         else if (flag & (EXP_GLOB | EXP_CASE))
 884                 STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
 885         else
 886                 STPUTS(p, expdest);
 887 }
 888
 889 static void
 890 reprocess(int startloc, int flag, int subtype, int quoted,
 891     struct worddest *dst)
 892 {
 893         static char *buf = NULL;
 894         static size_t buflen = 0;
 895         char *startp;
 896         size_t len, zpos, zlen;
 897
 898         startp = stackblock() + startloc;
 899         len = expdest - startp;
 900         if (len >= SIZE_MAX / 2 || len > PTRDIFF_MAX)
 901                 abort();
 902         INTOFF;
 903         if (len >= buflen) {
 904                 ckfree(buf);
 905                 buf = NULL;
 906         }
 907         if (buflen < 128)
 908                 buflen = 128;
 909         while (len >= buflen)
 910                 buflen <<= 1;
 911         if (buf == NULL)
 912                 buf = ckmalloc(buflen);
 913         INTON;
 914         memcpy(buf, startp, len);
 915         buf[len] = '\0';
 916         STADJUST(-(ptrdiff_t)len, expdest);
 917         for (zpos = 0;;) {
 918                 zlen = strlen(buf + zpos);
 919                 strtodest(buf + zpos, flag, subtype, quoted, dst);
 920                 zpos += zlen + 1;
 921                 if (zpos == len + 1)
 922                         break;
 923                 if (flag & EXP_SPLIT && (quoted || (zlen > 0 && zpos < len)))
 924                         NEXTWORD('\0', flag, expdest, dst);
 925         }
 926 }
 927
 928 /*
 929  * Add the value of a special or positional parameter to the stack string.
 930  */
 931
 932 static void
 933 varvalue(const char *name, int quoted, int subtype, int flag,
 934     struct worddest *dst)
 935 {
 936         int num;
 937         char *p;
 938         int i;
 939         int splitlater;
 940         char sep[2];
 941         char **ap;
 942         char buf[(NSHORTOPTS > 10 ? NSHORTOPTS : 10) + 1];
 943
 944         if (subtype == VSLENGTH)
 945                 flag &= ~EXP_FULL;
 946         splitlater = subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
 947                 subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX;
 948
 949         switch (*name) {
 950         case '$':
 951                 num = rootpid;
 952                 break;
 953         case '?':
 954                 num = oexitstatus;
 955                 break;
 956         case '#':
 957                 num = shellparam.nparam;
 958                 break;
 959         case '!':
 960                 num = backgndpidval();
 961                 break;
 962         case '-':
 963                 p = buf;
 964                 for (i = 0 ; i < NSHORTOPTS ; i++) {
 965                         if (optval[i])
 966                                 *p++ = optletter[i];
 967                 }
 968                 *p = '\0';
 969                 strtodest(buf, flag, subtype, quoted, dst);
 970                 return;
 971         case '@':
 972                 if (flag & EXP_SPLIT && quoted) {
 973                         for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 974                                 strtodest(p, flag, subtype, quoted, dst);
 975                                 if (*ap) {
 976                                         if (splitlater)
 977                                                 STPUTC('\0', expdest);
 978                                         else
 979                                                 NEXTWORD('\0', flag, expdest,
 980                                                     dst);
 981                                 }
 982                         }
 983                         if (shellparam.nparam > 0)
 984                                 dst->state = WORD_QUOTEMARK;
 985                         return;
 986                 }
 987                 /* FALLTHROUGH */
 988         case '*':
 989                 if (ifsset())
 990                         sep[0] = ifsval()[0];
 991                 else
 992                         sep[0] = ' ';
 993                 sep[1] = '\0';
 994                 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
 995                         strtodest(p, flag, subtype, quoted, dst);
 996                         if (!*ap)
 997                                 break;
 998                         if (sep[0])
 999                                 strtodest(sep, flag, subtype, quoted, dst);
1000                         else if (flag & EXP_SPLIT && !quoted && **ap != '\0') {
1001                                 if (splitlater)
1002                                         STPUTC('\0', expdest);
1003                                 else
1004                                         NEXTWORD('\0', flag, expdest, dst);
1005                         }
1006                 }
1007                 return;
1008         default:
1009                 if (is_digit(*name)) {
1010                         num = atoi(name);
1011                         if (num == 0)
1012                                 p = arg0;
1013                         else if (num > 0 && num <= shellparam.nparam)
1014                                 p = shellparam.p[num - 1];
1015                         else
1016                                 return;
1017                         strtodest(p, flag, subtype, quoted, dst);
1018                 }
1019                 return;
1020         }
1021         cvtnum(num, buf);
1022         strtodest(buf, flag, subtype, quoted, dst);
1023 }
1024
1025
1026
1027 static char expdir[PATH_MAX];
1028 #define expdir_end (expdir + sizeof(expdir))
1029
1030 /*
1031  * Perform pathname generation and remove control characters.
1032  * At this point, the only control characters should be CTLESC.
1033  * The results are stored in the list dstlist.
1034  */
1035 static void
1036 expandmeta(char *pattern, struct arglist *dstlist)
1037 {
1038         char *p;
1039         int firstmatch;
1040         char c;
1041
1042         firstmatch = dstlist->count;
1043         p = pattern;
1044         for (; (c = *p) != '\0'; p++) {
1045                 /* fast check for meta chars */
1046                 if (c == '*' || c == '?' || c == '[') {
1047                         INTOFF;
1048                         expmeta(expdir, pattern, dstlist);
1049                         INTON;
1050                         break;
1051                 }
1052         }
1053         if (dstlist->count == firstmatch) {
1054                 /*
1055                  * no matches
1056                  */
1057                 rmescapes(pattern);
1058                 appendarglist(dstlist, pattern);
1059         } else {
1060                 qsort(&dstlist->args[firstmatch],
1061                     dstlist->count - firstmatch,
1062                     sizeof(dstlist->args[0]), expsortcmp);
1063         }
1064 }
1065
1066
1067 /*
1068  * Do metacharacter (i.e. *, ?, [...]) expansion.
1069  */
1070
1071 static void
1072 expmeta(char *enddir, char *name, struct arglist *arglist)
1073 {
1074         const char *p;
1075         const char *q;
1076         const char *start;
1077         char *endname;
1078         int metaflag;
1079         struct stat statb;
1080         DIR *dirp;
1081         struct dirent *dp;
1082         int atend;
1083         int matchdot;
1084         int esc;
1085         int namlen;
1086
1087         metaflag = 0;
1088         start = name;
1089         for (p = name; esc = 0, *p; p += esc + 1) {
1090                 if (*p == '*' || *p == '?')
1091                         metaflag = 1;
1092                 else if (*p == '[') {
1093                         q = p + 1;
1094                         if (*q == '!' || *q == '^')
1095                                 q++;
1096                         for (;;) {
1097                                 if (*q == CTLESC)
1098                                         q++;
1099                                 if (*q == '/' || *q == '\0')
1100                                         break;
1101                                 if (*++q == ']') {
1102                                         metaflag = 1;
1103                                         break;
1104                                 }
1105                         }
1106                 } else if (*p == '\0')
1107                         break;
1108                 else {
1109                         if (*p == CTLESC)
1110                                 esc++;
1111                         if (p[esc] == '/') {
1112                                 if (metaflag)
1113                                         break;
1114                                 start = p + esc + 1;
1115                         }
1116                 }
1117         }
1118         if (metaflag == 0) {    /* we've reached the end of the file name */
1119                 if (enddir != expdir)
1120                         metaflag++;
1121                 for (p = name ; ; p++) {
1122                         if (*p == CTLESC)
1123                                 p++;
1124                         *enddir++ = *p;
1125                         if (*p == '\0')
1126                                 break;
1127                         if (enddir == expdir_end)
1128                                 return;
1129                 }
1130                 if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1131                         appendarglist(arglist, stsavestr(expdir));
1132                 return;
1133         }
1134         endname = name + (p - name);
1135         if (start != name) {
1136                 p = name;
1137                 while (p < start) {
1138                         if (*p == CTLESC)
1139                                 p++;
1140                         *enddir++ = *p++;
1141                         if (enddir == expdir_end)
1142                                 return;
1143                 }
1144         }
1145         if (enddir == expdir) {
1146                 p = ".";
1147         } else if (enddir == expdir + 1 && *expdir == '/') {
1148                 p = "/";
1149         } else {
1150                 p = expdir;
1151                 enddir[-1] = '\0';
1152         }
1153         if ((dirp = opendir(p)) == NULL)
1154                 return;
1155         if (enddir != expdir)
1156                 enddir[-1] = '/';
1157         if (*endname == 0) {
1158                 atend = 1;
1159         } else {
1160                 atend = 0;
1161                 *endname = '\0';
1162                 endname += esc + 1;
1163         }
1164         matchdot = 0;
1165         p = start;
1166         if (*p == CTLESC)
1167                 p++;
1168         if (*p == '.')
1169                 matchdot++;
1170         while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1171                 if (dp->d_name[0] == '.' && ! matchdot)
1172                         continue;
1173                 if (patmatch(start, dp->d_name)) {
1174 #ifdef _DIRENT_HAVE_D_NAMLEN
1175                         namlen = dp->d_namlen;
1176 #else
1177                         namlen = strlen(dp->d_name);
1178 #endif
1179                         if (enddir + namlen + 1 > expdir_end)
1180                                 continue;
1181                         memcpy(enddir, dp->d_name, namlen + 1);
1182                         if (atend)
1183                                 appendarglist(arglist, stsavestr(expdir));
1184                         else {
1185                                 if (dp->d_type != DT_UNKNOWN &&
1186                                     dp->d_type != DT_DIR &&
1187                                     dp->d_type != DT_LNK)
1188                                         continue;
1189                                 if (enddir + namlen + 2 > expdir_end)
1190                                         continue;
1191                                 enddir[namlen] = '/';
1192                                 enddir[namlen + 1] = '\0';
1193                                 expmeta(enddir + namlen + 1, endname, arglist);
1194                         }
1195                 }
1196         }
1197         closedir(dirp);
1198         if (! atend)
1199                 endname[-esc - 1] = esc ? CTLESC : '/';
1200 }
1201
1202
1203 static int
1204 expsortcmp(const void *p1, const void *p2)
1205 {
1206         const char *s1 = *(const char * const *)p1;
1207         const char *s2 = *(const char * const *)p2;
1208
1209         return (strcoll(s1, s2));
1210 }
1211
1212
1213
1214 static wchar_t
1215 get_wc(const char **p)
1216 {
1217         wchar_t c;
1218         int chrlen;
1219
1220         chrlen = mbtowc(&c, *p, 4);
1221         if (chrlen == 0)
1222                 return 0;
1223         else if (chrlen == -1)
1224                 c = 0;
1225         else
1226                 *p += chrlen;
1227         return c;
1228 }
1229
1230
1231 /*
1232  * See if a character matches a character class, starting at the first colon
1233  * of "[:class:]".
1234  * If a valid character class is recognized, a pointer to the next character
1235  * after the final closing bracket is stored into *end, otherwise a null
1236  * pointer is stored into *end.
1237  */
1238 static int
1239 match_charclass(const char *p, wchar_t chr, const char **end)
1240 {
1241         char name[20];
1242         const char *nameend;
1243         wctype_t cclass;
1244
1245         *end = NULL;
1246         p++;
1247         nameend = strstr(p, ":]");
1248         if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
1249             nameend == p)
1250                 return 0;
1251         memcpy(name, p, nameend - p);
1252         name[nameend - p] = '\0';
1253         *end = nameend + 2;
1254         cclass = wctype(name);
1255         /* An unknown class matches nothing but is valid nevertheless. */
1256         if (cclass == 0)
1257                 return 0;
1258         return iswctype(chr, cclass);
1259 }
1260
1261
1262 /*
1263  * Returns true if the pattern matches the string.
1264  */
1265
1266 static int
1267 patmatch(const char *pattern, const char *string)
1268 {
1269         const char *p, *q, *end;
1270         const char *bt_p, *bt_q;
1271         char c;
1272         wchar_t wc, wc2;
1273
1274         p = pattern;
1275         q = string;
1276         bt_p = NULL;
1277         bt_q = NULL;
1278         for (;;) {
1279                 switch (c = *p++) {
1280                 case '\0':
1281                         if (*q != '\0')
1282                                 goto backtrack;
1283                         return 1;
1284                 case CTLESC:
1285                         if (*q++ != *p++)
1286                                 goto backtrack;
1287                         break;
1288                 case '?':
1289                         if (*q == '\0')
1290                                 return 0;
1291                         if (localeisutf8) {
1292                                 wc = get_wc(&q);
1293                                 /*
1294                                  * A '?' does not match invalid UTF-8 but a
1295                                  * '*' does, so backtrack.
1296                                  */
1297                                 if (wc == 0)
1298                                         goto backtrack;
1299                         } else
1300                                 q++;
1301                         break;
1302                 case '*':
1303                         c = *p;
1304                         while (c == '*')
1305                                 c = *++p;
1306                         /*
1307                          * If the pattern ends here, we know the string
1308                          * matches without needing to look at the rest of it.
1309                          */
1310                         if (c == '\0')
1311                                 return 1;
1312                         /*
1313                          * First try the shortest match for the '*' that
1314                          * could work. We can forget any earlier '*' since
1315                          * there is no way having it match more characters
1316                          * can help us, given that we are already here.
1317                          */
1318                         bt_p = p;
1319                         bt_q = q;
1320                         break;
1321                 case '[': {
1322                         const char *savep, *saveq;
1323                         int invert, found;
1324                         wchar_t chr;
1325
1326                         savep = p, saveq = q;
1327                         invert = 0;
1328                         if (*p == '!' || *p == '^') {
1329                                 invert++;
1330                                 p++;
1331                         }
1332                         found = 0;
1333                         if (*q == '\0')
1334                                 return 0;
1335                         if (localeisutf8) {
1336                                 chr = get_wc(&q);
1337                                 if (chr == 0)
1338                                         goto backtrack;
1339                         } else
1340                                 chr = (unsigned char)*q++;
1341                         c = *p++;
1342                         do {
1343                                 if (c == '\0') {
1344                                         p = savep, q = saveq;
1345                                         c = '[';
1346                                         goto dft;
1347                                 }
1348                                 if (c == '[' && *p == ':') {
1349                                         found |= match_charclass(p, chr, &end);
1350                                         if (end != NULL) {
1351                                                 p = end;
1352                                                 continue;
1353                                         }
1354                                 }
1355                                 if (c == CTLESC)
1356                                         c = *p++;
1357                                 if (localeisutf8 && c & 0x80) {
1358                                         p--;
1359                                         wc = get_wc(&p);
1360                                         if (wc == 0) /* bad utf-8 */
1361                                                 return 0;
1362                                 } else
1363                                         wc = (unsigned char)c;
1364                                 if (*p == '-' && p[1] != ']') {
1365                                         p++;
1366                                         if (*p == CTLESC)
1367                                                 p++;
1368                                         if (localeisutf8) {
1369                                                 wc2 = get_wc(&p);
1370                                                 if (wc2 == 0) /* bad utf-8 */
1371                                                         return 0;
1372                                         } else
1373                                                 wc2 = (unsigned char)*p++;
1374                                         if (   collate_range_cmp(chr, wc) >= 0
1375                                             && collate_range_cmp(chr, wc2) <= 0
1376                                            )
1377                                                 found = 1;
1378                                 } else {
1379                                         if (chr == wc)
1380                                                 found = 1;
1381                                 }
1382                         } while ((c = *p++) != ']');
1383                         if (found == invert)
1384                                 goto backtrack;
1385                         break;
1386                 }
1387 dft:            default:
1388                         if (*q == '\0')
1389                                 return 0;
1390                         if (*q++ == c)
1391                                 break;
1392 backtrack:
1393                         /*
1394                          * If we have a mismatch (other than hitting the end
1395                          * of the string), go back to the last '*' seen and
1396                          * have it match one additional character.
1397                          */
1398                         if (bt_p == NULL)
1399                                 return 0;
1400                         if (*bt_q == '\0')
1401                                 return 0;
1402                         bt_q++;
1403                         p = bt_p;
1404                         q = bt_q;
1405                         break;
1406                 }
1407         }
1408 }
1409
1410
1411
1412 /*
1413  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1414  */
1415
1416 void
1417 rmescapes(char *str)
1418 {
1419         char *p, *q;
1420
1421         p = str;
1422         while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1423                 if (*p++ == '\0')
1424                         return;
1425         }
1426         q = p;
1427         while (*p) {
1428                 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1429                         p++;
1430                         continue;
1431                 }
1432                 if (*p == CTLESC)
1433                         p++;
1434                 *q++ = *p++;
1435         }
1436         *q = '\0';
1437 }
1438
1439
1440
1441 /*
1442  * See if a pattern matches in a case statement.
1443  */
1444
1445 int
1446 casematch(union node *pattern, const char *val)
1447 {
1448         struct stackmark smark;
1449         struct nodelist *argbackq;
1450         int result;
1451         char *p;
1452
1453         setstackmark(&smark);
1454         argbackq = pattern->narg.backquote;
1455         STARTSTACKSTR(expdest);
1456         argstr(pattern->narg.text, &argbackq, EXP_TILDE | EXP_CASE, NULL);
1457         STPUTC('\0', expdest);
1458         p = grabstackstr(expdest);
1459         result = patmatch(p, val);
1460         popstackmark(&smark);
1461         return result;
1462 }
1463
1464 /*
1465  * Our own itoa().
1466  */
1467
1468 static void
1469 cvtnum(int num, char *buf)
1470 {
1471         char temp[32];
1472         int neg = num < 0;
1473         char *p = temp + 31;
1474
1475         temp[31] = '\0';
1476
1477         do {
1478                 *--p = num % 10 + '0';
1479         } while ((num /= 10) != 0);
1480
1481         if (neg)
1482                 *--p = '-';
1483
1484         memcpy(buf, p, temp + 32 - p);
1485 }
1486
1487 /*
1488  * Do most of the work for wordexp(3).
1489  */
1490
1491 int
1492 wordexpcmd(int argc, char **argv)
1493 {
1494         size_t len;
1495         int i;
1496
1497         out1fmt("%08x", argc - 1);
1498         for (i = 1, len = 0; i < argc; i++)
1499                 len += strlen(argv[i]);
1500         out1fmt("%08x", (int)len);
1501         for (i = 1; i < argc; i++)
1502                 outbin(argv[i], strlen(argv[i]) + 1, out1);
1503         return (0);
1504 }
1505
1506 /*
1507  * Do most of the work for wordexp(3), new version.
1508  */
1509
1510 int
1511 wordexp2cmd(int argc __unused, char **argv __unused)
1512 {
1513         struct arglist arglist;
1514         union node *args, *n;
1515         size_t len;
1516         int ch;
1517         int protected = 0;
1518         int fd = -1;
1519         int i;
1520
1521         while ((ch = nextopt("f:p")) != '\0') {
1522                 switch (ch) {
1523                 case 'f':
1524                         fd = number(shoptarg);
1525                         break;
1526                 case 'p':
1527                         protected = 1;
1528                         break;
1529                 }
1530         }
1531         if (*argptr != NULL)
1532                 error("wrong number of arguments");
1533         if (fd < 0)
1534                 error("missing fd");
1535         INTOFF;
1536         setinputfd(fd, 1);
1537         INTON;
1538         args = parsewordexp();
1539         popfile(); /* will also close fd */
1540         if (protected)
1541                 for (n = args; n != NULL; n = n->narg.next) {
1542                         if (n->narg.backquote != NULL) {
1543                                 outcslow('C', out1);
1544                                 error("command substitution disabled");
1545                         }
1546                 }
1547         outcslow(' ', out1);
1548         emptyarglist(&arglist);
1549         for (n = args; n != NULL; n = n->narg.next)
1550                 expandarg(n, &arglist, EXP_FULL | EXP_TILDE);
1551         for (i = 0, len = 0; i < arglist.count; i++)
1552                 len += strlen(arglist.args[i]);
1553         out1fmt("%016x %016zx", arglist.count, len);
1554         for (i = 0; i < arglist.count; i++)
1555                 outbin(arglist.args[i], strlen(arglist.args[i]) + 1, out1);
1556         return (0);
1557 }