cbe4b62709cc6f3276744f079ba3db48813f7fd8
[dragonfly.git] / bin / sh / expand.c
1 /*-
2  * Copyright (c) 1991, 1993
3  *      The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1997-2005
5  *      Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Kenneth Almquist.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. 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  * @(#)expand.c 8.5 (Berkeley) 5/15/95
35  * $FreeBSD: head/bin/sh/expand.c 248980 2013-04-01 17:18:22Z jilles $
36  */
37
38 #include <sys/types.h>
39 #include <sys/time.h>
40 #include <sys/stat.h>
41 #include <dirent.h>
42 #include <errno.h>
43 #include <inttypes.h>
44 #include <limits.h>
45 #include <pwd.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <wchar.h>
51 #include <wctype.h>
52
53 /*
54  * Routines to expand arguments to commands.  We have to deal with
55  * backquotes, shell variables, and file metacharacters.
56  */
57
58 #include "shell.h"
59 #include "main.h"
60 #include "nodes.h"
61 #include "eval.h"
62 #include "expand.h"
63 #include "syntax.h"
64 #include "parser.h"
65 #include "jobs.h"
66 #include "options.h"
67 #include "var.h"
68 #include "input.h"
69 #include "output.h"
70 #include "memalloc.h"
71 #include "error.h"
72 #include "mystring.h"
73 #include "arith.h"
74 #include "show.h"
75 #include "builtins.h"
76
77 /*
78  * Structure specifying which parts of the string should be searched
79  * for IFS characters.
80  */
81
82 struct ifsregion {
83         struct ifsregion *next; /* next region in list */
84         int begoff;             /* offset of start of region */
85         int endoff;             /* offset of end of region */
86         int inquotes;           /* search for nul bytes only */
87 };
88
89
90 static char *expdest;                   /* output of current string */
91 static struct nodelist *argbackq;       /* list of back quote expressions */
92 static struct ifsregion ifsfirst;       /* first struct in list of ifs regions */
93 static struct ifsregion *ifslastp;      /* last struct in list */
94 static struct arglist exparg;           /* holds expanded arg list */
95
96 static void argstr(char *, int);
97 static char *exptilde(char *, int);
98 static void expbackq(union node *, int, int);
99 static int subevalvar(char *, char *, int, int, int, int, int);
100 static char *evalvar(char *, int);
101 static int varisset(char *, int);
102 static void varvalue(char *, int, int, int);
103 static void recordregion(int, int, int);
104 static void removerecordregions(int);
105 static void ifsbreakup(char *, struct arglist *);
106 static void expandmeta(struct strlist *, int);
107 static void expmeta(char *, char *);
108 static void addfname(char *);
109 static struct strlist *expsort(struct strlist *);
110 static struct strlist *msort(struct strlist *, int);
111 static int patmatch(const char *, const char *, int);
112 static char *cvtnum(int, char *);
113 static int collate_range_cmp(wchar_t, wchar_t);
114
115 static int
116 collate_range_cmp(wchar_t c1, wchar_t c2)
117 {
118         static wchar_t s1[2], s2[2];
119
120         s1[0] = c1;
121         s2[0] = c2;
122         return (wcscoll(s1, s2));
123 }
124
125 static char *
126 stputs_quotes(const char *data, const char *syntax, char *p)
127 {
128         while (*data) {
129                 CHECKSTRSPACE(2, p);
130                 if (syntax[(int)*data] == CCTL)
131                         USTPUTC(CTLESC, p);
132                 USTPUTC(*data++, p);
133         }
134         return (p);
135 }
136 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
137
138 /*
139  * Perform expansions on an argument, placing the resulting list of arguments
140  * in arglist.  Parameter expansion, command substitution and arithmetic
141  * expansion are always performed; additional expansions can be requested
142  * via flag (EXP_*).
143  * The result is left in the stack string.
144  * When arglist is NULL, perform here document expansion.
145  *
146  * Caution: this function uses global state and is not reentrant.
147  * However, a new invocation after an interrupted invocation is safe
148  * and will reset the global state for the new call.
149  */
150 void
151 expandarg(union node *arg, struct arglist *arglist, int flag)
152 {
153         struct strlist *sp;
154         char *p;
155
156         argbackq = arg->narg.backquote;
157         STARTSTACKSTR(expdest);
158         ifsfirst.next = NULL;
159         ifslastp = NULL;
160         argstr(arg->narg.text, flag);
161         if (arglist == NULL) {
162                 STACKSTRNUL(expdest);
163                 return;                 /* here document expanded */
164         }
165         STPUTC('\0', expdest);
166         p = grabstackstr(expdest);
167         exparg.lastp = &exparg.list;
168         /*
169          * TODO - EXP_REDIR
170          */
171         if (flag & EXP_FULL) {
172                 ifsbreakup(p, &exparg);
173                 *exparg.lastp = NULL;
174                 exparg.lastp = &exparg.list;
175                 expandmeta(exparg.list, flag);
176         } else {
177                 if (flag & EXP_REDIR) /*XXX - for now, just remove escapes */
178                         rmescapes(p);
179                 sp = (struct strlist *)stalloc(sizeof (struct strlist));
180                 sp->text = p;
181                 *exparg.lastp = sp;
182                 exparg.lastp = &sp->next;
183         }
184         while (ifsfirst.next != NULL) {
185                 struct ifsregion *ifsp;
186                 INTOFF;
187                 ifsp = ifsfirst.next->next;
188                 ckfree(ifsfirst.next);
189                 ifsfirst.next = ifsp;
190                 INTON;
191         }
192         *exparg.lastp = NULL;
193         if (exparg.list) {
194                 *arglist->lastp = exparg.list;
195                 arglist->lastp = exparg.lastp;
196         }
197 }
198
199
200
201 /*
202  * Perform parameter expansion, command substitution and arithmetic
203  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
204  * Processing ends at a CTLENDVAR character as well as '\0'.
205  * This is used to expand word in ${var+word} etc.
206  * If EXP_FULL, EXP_CASE or EXP_REDIR are set, keep and/or generate CTLESC
207  * characters to allow for further processing.
208  * If EXP_FULL is set, also preserve CTLQUOTEMARK characters.
209  */
210 static void
211 argstr(char *p, int flag)
212 {
213         char c;
214         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);  /* do CTLESC */
215         int firsteq = 1;
216         int split_lit;
217         int lit_quoted;
218
219         split_lit = flag & EXP_SPLIT_LIT;
220         lit_quoted = flag & EXP_LIT_QUOTED;
221         flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
222         if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
223                 p = exptilde(p, flag);
224         for (;;) {
225                 CHECKSTRSPACE(2, expdest);
226                 switch (c = *p++) {
227                 case '\0':
228                 case CTLENDVAR:
229                         goto breakloop;
230                 case CTLQUOTEMARK:
231                         lit_quoted = 1;
232                         /* "$@" syntax adherence hack */
233                         if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
234                                 break;
235                         if ((flag & EXP_FULL) != 0)
236                                 USTPUTC(c, expdest);
237                         break;
238                 case CTLQUOTEEND:
239                         lit_quoted = 0;
240                         break;
241                 case CTLESC:
242                         if (quotes)
243                                 USTPUTC(c, expdest);
244                         c = *p++;
245                         USTPUTC(c, expdest);
246                         if (split_lit && !lit_quoted)
247                                 recordregion(expdest - stackblock() -
248                                     (quotes ? 2 : 1),
249                                     expdest - stackblock(), 0);
250                         break;
251                 case CTLVAR:
252                         p = evalvar(p, flag);
253                         break;
254                 case CTLBACKQ:
255                 case CTLBACKQ|CTLQUOTE:
256                         expbackq(argbackq->n, c & CTLQUOTE, flag);
257                         argbackq = argbackq->next;
258                         break;
259                 case CTLENDARI:
260                         expari(flag);
261                         break;
262                 case ':':
263                 case '=':
264                         /*
265                          * sort of a hack - expand tildes in variable
266                          * assignments (after the first '=' and after ':'s).
267                          */
268                         USTPUTC(c, expdest);
269                         if (split_lit && !lit_quoted)
270                                 recordregion(expdest - stackblock() - 1,
271                                     expdest - stackblock(), 0);
272                         if (flag & EXP_VARTILDE && *p == '~' &&
273                             (c != '=' || firsteq)) {
274                                 if (c == '=')
275                                         firsteq = 0;
276                                 p = exptilde(p, flag);
277                         }
278                         break;
279                 default:
280                         USTPUTC(c, expdest);
281                         if (split_lit && !lit_quoted)
282                                 recordregion(expdest - stackblock() - 1,
283                                     expdest - stackblock(), 0);
284                 }
285         }
286 breakloop:;
287 }
288
289 /*
290  * Perform tilde expansion, placing the result in the stack string and
291  * returning the next position in the input string to process.
292  */
293 static char *
294 exptilde(char *p, int flag)
295 {
296         char c, *startp = p;
297         struct passwd *pw;
298         char *home;
299         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
300
301         while ((c = *p) != '\0') {
302                 switch(c) {
303                 case CTLESC: /* This means CTL* are always considered quoted. */
304                 case CTLVAR:
305                 case CTLBACKQ:
306                 case CTLBACKQ | CTLQUOTE:
307                 case CTLARI:
308                 case CTLENDARI:
309                 case CTLQUOTEMARK:
310                         return (startp);
311                 case ':':
312                         if (flag & EXP_VARTILDE)
313                                 goto done;
314                         break;
315                 case '/':
316                 case CTLENDVAR:
317                         goto done;
318                 }
319                 p++;
320         }
321 done:
322         *p = '\0';
323         if (*(startp+1) == '\0') {
324                 if ((home = lookupvar("HOME")) == NULL)
325                         goto lose;
326         } else {
327                 if ((pw = getpwnam(startp+1)) == NULL)
328                         goto lose;
329                 home = pw->pw_dir;
330         }
331         if (*home == '\0')
332                 goto lose;
333         *p = c;
334         if (quotes)
335                 STPUTS_QUOTES(home, SQSYNTAX, expdest);
336         else
337                 STPUTS(home, expdest);
338         return (p);
339 lose:
340         *p = c;
341         return (startp);
342 }
343
344
345 static void
346 removerecordregions(int endoff)
347 {
348         if (ifslastp == NULL)
349                 return;
350
351         if (ifsfirst.endoff > endoff) {
352                 while (ifsfirst.next != NULL) {
353                         struct ifsregion *ifsp;
354                         INTOFF;
355                         ifsp = ifsfirst.next->next;
356                         ckfree(ifsfirst.next);
357                         ifsfirst.next = ifsp;
358                         INTON;
359                 }
360                 if (ifsfirst.begoff > endoff)
361                         ifslastp = NULL;
362                 else {
363                         ifslastp = &ifsfirst;
364                         ifsfirst.endoff = endoff;
365                 }
366                 return;
367         }
368
369         ifslastp = &ifsfirst;
370         while (ifslastp->next && ifslastp->next->begoff < endoff)
371                 ifslastp=ifslastp->next;
372         while (ifslastp->next != NULL) {
373                 struct ifsregion *ifsp;
374                 INTOFF;
375                 ifsp = ifslastp->next->next;
376                 ckfree(ifslastp->next);
377                 ifslastp->next = ifsp;
378                 INTON;
379         }
380         if (ifslastp->endoff > endoff)
381                 ifslastp->endoff = endoff;
382 }
383
384 /*
385  * Expand arithmetic expression.  Backup to start of expression,
386  * evaluate, place result in (backed up) result, adjust string position.
387  */
388 void
389 expari(int flag)
390 {
391         char *p, *q, *start;
392         arith_t result;
393         int begoff;
394         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
395         int quoted;
396
397         /*
398          * This routine is slightly over-complicated for
399          * efficiency.  First we make sure there is
400          * enough space for the result, which may be bigger
401          * than the expression.  Next we
402          * scan backwards looking for the start of arithmetic.  If the
403          * next previous character is a CTLESC character, then we
404          * have to rescan starting from the beginning since CTLESC
405          * characters have to be processed left to right.
406          */
407         CHECKSTRSPACE(DIGITS(result) - 2, expdest);
408         USTPUTC('\0', expdest);
409         start = stackblock();
410         p = expdest - 2;
411         while (p >= start && *p != CTLARI)
412                 --p;
413         if (p < start || *p != CTLARI)
414                 error("missing CTLARI (shouldn't happen)");
415         if (p > start && *(p - 1) == CTLESC)
416                 for (p = start; *p != CTLARI; p++)
417                         if (*p == CTLESC)
418                                 p++;
419
420         if (p[1] == '"')
421                 quoted=1;
422         else
423                 quoted=0;
424         begoff = p - start;
425         removerecordregions(begoff);
426         if (quotes)
427                 rmescapes(p+2);
428         q = grabstackstr(expdest);
429         result = arith(p+2);
430         ungrabstackstr(q, expdest);
431         fmtstr(p, DIGITS(result), ARITH_FORMAT_STR, result);
432         while (*p++)
433                 ;
434         if (quoted == 0)
435                 recordregion(begoff, p - 1 - start, 0);
436         result = expdest - p + 1;
437         STADJUST(-result, expdest);
438 }
439
440
441 /*
442  * Perform command substitution.
443  */
444 static void
445 expbackq(union node *cmd, int quoted, int flag)
446 {
447         struct backcmd in;
448         int i;
449         char buf[128];
450         char *p;
451         char *dest = expdest;
452         struct ifsregion saveifs, *savelastp;
453         struct nodelist *saveargbackq;
454         char lastc;
455         int startloc = dest - stackblock();
456         char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
457         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
458         size_t nnl;
459
460         INTOFF;
461         saveifs = ifsfirst;
462         savelastp = ifslastp;
463         saveargbackq = argbackq;
464         p = grabstackstr(dest);
465         evalbackcmd(cmd, &in);
466         ungrabstackstr(p, dest);
467         ifsfirst = saveifs;
468         ifslastp = savelastp;
469         argbackq = saveargbackq;
470
471         p = in.buf;
472         lastc = '\0';
473         nnl = 0;
474         /* Don't copy trailing newlines */
475         for (;;) {
476                 if (--in.nleft < 0) {
477                         if (in.fd < 0)
478                                 break;
479                         while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
480                         TRACE(("expbackq: read returns %d\n", i));
481                         if (i <= 0)
482                                 break;
483                         p = buf;
484                         in.nleft = i - 1;
485                 }
486                 lastc = *p++;
487                 if (lastc != '\0') {
488                         if (lastc == '\n') {
489                                 nnl++;
490                         } else {
491                                 CHECKSTRSPACE(nnl + 2, dest);
492                                 while (nnl > 0) {
493                                         nnl--;
494                                         USTPUTC('\n', dest);
495                                 }
496                                 if (quotes && syntax[(int)lastc] == CCTL)
497                                         USTPUTC(CTLESC, dest);
498                                 USTPUTC(lastc, dest);
499                         }
500                 }
501         }
502
503         if (in.fd >= 0)
504                 close(in.fd);
505         if (in.buf)
506                 ckfree(in.buf);
507         if (in.jp)
508                 exitstatus = waitforjob(in.jp, NULL);
509         if (quoted == 0)
510                 recordregion(startloc, dest - stackblock(), 0);
511         TRACE(("expbackq: size=%td: \"%.*s\"\n",
512                 ((dest - stackblock()) - startloc),
513                 (int)((dest - stackblock()) - startloc),
514                 stackblock() + startloc));
515         expdest = dest;
516         INTON;
517 }
518
519
520
521 static int
522 subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
523   int varflags, int quotes)
524 {
525         char *startp;
526         char *loc = NULL;
527         char *q;
528         int c = 0;
529         struct nodelist *saveargbackq = argbackq;
530         int amount;
531
532         argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
533             subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ?
534             EXP_CASE : 0) | EXP_TILDE);
535         STACKSTRNUL(expdest);
536         argbackq = saveargbackq;
537         startp = stackblock() + startloc;
538         if (str == NULL)
539             str = stackblock() + strloc;
540
541         switch (subtype) {
542         case VSASSIGN:
543                 setvar(str, startp, 0);
544                 amount = startp - expdest;
545                 STADJUST(amount, expdest);
546                 varflags &= ~VSNUL;
547                 return 1;
548
549         case VSQUESTION:
550                 if (*p != CTLENDVAR) {
551                         outfmt(out2, "%s\n", startp);
552                         error(NULL);
553                 }
554                 error("%.*s: parameter %snot set", (int)(p - str - 1),
555                       str, (varflags & VSNUL) ? "null or "
556                                               : nullstr);
557                 return 0;
558
559         case VSTRIMLEFT:
560                 for (loc = startp; loc < str; loc++) {
561                         c = *loc;
562                         *loc = '\0';
563                         if (patmatch(str, startp, quotes)) {
564                                 *loc = c;
565                                 goto recordleft;
566                         }
567                         *loc = c;
568                         if (quotes && *loc == CTLESC)
569                                 loc++;
570                 }
571                 return 0;
572
573         case VSTRIMLEFTMAX:
574                 for (loc = str - 1; loc >= startp;) {
575                         c = *loc;
576                         *loc = '\0';
577                         if (patmatch(str, startp, quotes)) {
578                                 *loc = c;
579                                 goto recordleft;
580                         }
581                         *loc = c;
582                         loc--;
583                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
584                                 for (q = startp; q < loc; q++)
585                                         if (*q == CTLESC)
586                                                 q++;
587                                 if (q > loc)
588                                         loc--;
589                         }
590                 }
591                 return 0;
592
593         case VSTRIMRIGHT:
594                 for (loc = str - 1; loc >= startp;) {
595                         if (patmatch(str, loc, quotes)) {
596                                 amount = loc - expdest;
597                                 STADJUST(amount, expdest);
598                                 return 1;
599                         }
600                         loc--;
601                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
602                                 for (q = startp; q < loc; q++)
603                                         if (*q == CTLESC)
604                                                 q++;
605                                 if (q > loc)
606                                         loc--;
607                         }
608                 }
609                 return 0;
610
611         case VSTRIMRIGHTMAX:
612                 for (loc = startp; loc < str - 1; loc++) {
613                         if (patmatch(str, loc, quotes)) {
614                                 amount = loc - expdest;
615                                 STADJUST(amount, expdest);
616                                 return 1;
617                         }
618                         if (quotes && *loc == CTLESC)
619                                 loc++;
620                 }
621                 return 0;
622
623
624         default:
625                 abort();
626         }
627
628 recordleft:
629         amount = ((str - 1) - (loc - startp)) - expdest;
630         STADJUST(amount, expdest);
631         while (loc != str - 1)
632                 *startp++ = *loc++;
633         return 1;
634 }
635
636
637 /*
638  * Expand a variable, and return a pointer to the next character in the
639  * input string.
640  */
641
642 static char *
643 evalvar(char *p, int flag)
644 {
645         int subtype;
646         int varflags;
647         char *var;
648         char *val;
649         int patloc;
650         int c;
651         int set;
652         int special;
653         int startloc;
654         int varlen;
655         int varlenb;
656         int easy;
657         int quotes = flag & (EXP_FULL | EXP_CASE | EXP_REDIR);
658
659         varflags = (unsigned char)*p++;
660         subtype = varflags & VSTYPE;
661         var = p;
662         special = 0;
663         if (! is_name(*p))
664                 special = 1;
665         p = strchr(p, '=') + 1;
666 again: /* jump here after setting a variable with ${var=text} */
667         if (varflags & VSLINENO) {
668                 set = 1;
669                 special = 0;
670                 val = var;
671                 p[-1] = '\0';   /* temporarily overwrite '=' to have \0
672                                    terminated string */
673         } else if (special) {
674                 set = varisset(var, varflags & VSNUL);
675                 val = NULL;
676         } else {
677                 val = bltinlookup(var, 1);
678                 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
679                         val = NULL;
680                         set = 0;
681                 } else
682                         set = 1;
683         }
684         varlen = 0;
685         startloc = expdest - stackblock();
686         if (!set && uflag && *var != '@' && *var != '*') {
687                 switch (subtype) {
688                 case VSNORMAL:
689                 case VSTRIMLEFT:
690                 case VSTRIMLEFTMAX:
691                 case VSTRIMRIGHT:
692                 case VSTRIMRIGHTMAX:
693                 case VSLENGTH:
694                         error("%.*s: parameter not set", (int)(p - var - 1),
695                             var);
696                 }
697         }
698         if (set && subtype != VSPLUS) {
699                 /* insert the value of the variable */
700                 if (special) {
701                         varvalue(var, varflags & VSQUOTE, subtype, flag);
702                         if (subtype == VSLENGTH) {
703                                 varlenb = expdest - stackblock() - startloc;
704                                 varlen = varlenb;
705                                 if (localeisutf8) {
706                                         val = stackblock() + startloc;
707                                         for (;val != expdest; val++)
708                                                 if ((*val & 0xC0) == 0x80)
709                                                         varlen--;
710                                 }
711                                 STADJUST(-varlenb, expdest);
712                         }
713                 } else {
714                         char const *syntax = (varflags & VSQUOTE) ? DQSYNTAX
715                                                                   : BASESYNTAX;
716
717                         if (subtype == VSLENGTH) {
718                                 for (;*val; val++)
719                                         if (!localeisutf8 ||
720                                             (*val & 0xC0) != 0x80)
721                                                 varlen++;
722                         }
723                         else {
724                                 if (quotes)
725                                         STPUTS_QUOTES(val, syntax, expdest);
726                                 else
727                                         STPUTS(val, expdest);
728
729                         }
730                 }
731         }
732
733         if (subtype == VSPLUS)
734                 set = ! set;
735
736         easy = ((varflags & VSQUOTE) == 0 ||
737                 (*var == '@' && shellparam.nparam != 1));
738
739
740         switch (subtype) {
741         case VSLENGTH:
742                 expdest = cvtnum(varlen, expdest);
743                 goto record;
744
745         case VSNORMAL:
746                 if (!easy)
747                         break;
748 record:
749                 recordregion(startloc, expdest - stackblock(),
750                     varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
751                     (*var == '@' || *var == '*')));
752                 break;
753
754         case VSPLUS:
755         case VSMINUS:
756                 if (!set) {
757                         argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
758                             (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
759                         break;
760                 }
761                 if (easy)
762                         goto record;
763                 break;
764
765         case VSTRIMLEFT:
766         case VSTRIMLEFTMAX:
767         case VSTRIMRIGHT:
768         case VSTRIMRIGHTMAX:
769                 if (!set)
770                         break;
771                 /*
772                  * Terminate the string and start recording the pattern
773                  * right after it
774                  */
775                 STPUTC('\0', expdest);
776                 patloc = expdest - stackblock();
777                 if (subevalvar(p, NULL, patloc, subtype,
778                     startloc, varflags, quotes) == 0) {
779                         int amount = (expdest - stackblock() - patloc) + 1;
780                         STADJUST(-amount, expdest);
781                 }
782                 /* Remove any recorded regions beyond start of variable */
783                 removerecordregions(startloc);
784                 goto record;
785
786         case VSASSIGN:
787         case VSQUESTION:
788                 if (!set) {
789                         if (subevalvar(p, var, 0, subtype, startloc, varflags,
790                             quotes)) {
791                                 varflags &= ~VSNUL;
792                                 /*
793                                  * Remove any recorded regions beyond
794                                  * start of variable
795                                  */
796                                 removerecordregions(startloc);
797                                 goto again;
798                         }
799                         break;
800                 }
801                 if (easy)
802                         goto record;
803                 break;
804
805         case VSERROR:
806                 c = p - var - 1;
807                 error("${%.*s%s}: Bad substitution", c, var,
808                     (c > 0 && *p != CTLENDVAR) ? "..." : "");
809
810         default:
811                 abort();
812         }
813         p[-1] = '=';    /* recover overwritten '=' */
814
815         if (subtype != VSNORMAL) {      /* skip to end of alternative */
816                 int nesting = 1;
817                 for (;;) {
818                         if ((c = *p++) == CTLESC)
819                                 p++;
820                         else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
821                                 if (set)
822                                         argbackq = argbackq->next;
823                         } else if (c == CTLVAR) {
824                                 if ((*p++ & VSTYPE) != VSNORMAL)
825                                         nesting++;
826                         } else if (c == CTLENDVAR) {
827                                 if (--nesting == 0)
828                                         break;
829                         }
830                 }
831         }
832         return p;
833 }
834
835
836
837 /*
838  * Test whether a specialized variable is set.
839  */
840
841 static int
842 varisset(char *name, int nulok)
843 {
844
845         if (*name == '!')
846                 return backgndpidset();
847         else if (*name == '@' || *name == '*') {
848                 if (*shellparam.p == NULL)
849                         return 0;
850
851                 if (nulok) {
852                         char **av;
853
854                         for (av = shellparam.p; *av; av++)
855                                 if (**av != '\0')
856                                         return 1;
857                         return 0;
858                 }
859         } else if (is_digit(*name)) {
860                 char *ap;
861                 int num = atoi(name);
862
863                 if (num > shellparam.nparam)
864                         return 0;
865
866                 if (num == 0)
867                         ap = arg0;
868                 else
869                         ap = shellparam.p[num - 1];
870
871                 if (nulok && (ap == NULL || *ap == '\0'))
872                         return 0;
873         }
874         return 1;
875 }
876
877 static void
878 strtodest(const char *p, int flag, int subtype, int quoted)
879 {
880         if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH)
881                 STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
882         else
883                 STPUTS(p, expdest);
884 }
885
886 /*
887  * Add the value of a specialized variable to the stack string.
888  */
889
890 static void
891 varvalue(char *name, int quoted, int subtype, int flag)
892 {
893         int num;
894         char *p;
895         int i;
896         char sep;
897         char **ap;
898
899         switch (*name) {
900         case '$':
901                 num = rootpid;
902                 goto numvar;
903         case '?':
904                 num = oexitstatus;
905                 goto numvar;
906         case '#':
907                 num = shellparam.nparam;
908                 goto numvar;
909         case '!':
910                 num = backgndpidval();
911 numvar:
912                 expdest = cvtnum(num, expdest);
913                 break;
914         case '-':
915                 for (i = 0 ; i < NOPTS ; i++) {
916                         if (optlist[i].val)
917                                 STPUTC(optlist[i].letter, expdest);
918                 }
919                 break;
920         case '@':
921                 if (flag & EXP_FULL && quoted) {
922                         for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
923                                 strtodest(p, flag, subtype, quoted);
924                                 if (*ap)
925                                         STPUTC('\0', expdest);
926                         }
927                         break;
928                 }
929                 /* FALLTHROUGH */
930         case '*':
931                 if (ifsset())
932                         sep = ifsval()[0];
933                 else
934                         sep = ' ';
935                 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
936                         strtodest(p, flag, subtype, quoted);
937                         if (!*ap)
938                                 break;
939                         if (sep || (flag & EXP_FULL && !quoted && **ap != '\0'))
940                                 STPUTC(sep, expdest);
941                 }
942                 break;
943         case '0':
944                 p = arg0;
945                 strtodest(p, flag, subtype, quoted);
946                 break;
947         default:
948                 if (is_digit(*name)) {
949                         num = atoi(name);
950                         if (num > 0 && num <= shellparam.nparam) {
951                                 p = shellparam.p[num - 1];
952                                 strtodest(p, flag, subtype, quoted);
953                         }
954                 }
955                 break;
956         }
957 }
958
959
960
961 /*
962  * Record the fact that we have to scan this region of the
963  * string for IFS characters.
964  */
965
966 static void
967 recordregion(int start, int end, int inquotes)
968 {
969         struct ifsregion *ifsp;
970
971         if (ifslastp == NULL) {
972                 ifsp = &ifsfirst;
973         } else {
974                 if (ifslastp->endoff == start
975                     && ifslastp->inquotes == inquotes) {
976                         /* extend previous area */
977                         ifslastp->endoff = end;
978                         return;
979                 }
980                 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
981                 ifslastp->next = ifsp;
982         }
983         ifslastp = ifsp;
984         ifslastp->next = NULL;
985         ifslastp->begoff = start;
986         ifslastp->endoff = end;
987         ifslastp->inquotes = inquotes;
988 }
989
990
991
992 /*
993  * Break the argument string into pieces based upon IFS and add the
994  * strings to the argument list.  The regions of the string to be
995  * searched for IFS characters have been stored by recordregion.
996  * CTLESC characters are preserved but have little effect in this pass
997  * other than escaping CTL* characters.  In particular, they do not escape
998  * IFS characters: that should be done with the ifsregion mechanism.
999  * CTLQUOTEMARK characters are used to preserve empty quoted strings.
1000  * This pass treats them as a regular character, making the string non-empty.
1001  * Later, they are removed along with the other CTL* characters.
1002  */
1003 static void
1004 ifsbreakup(char *string, struct arglist *arglist)
1005 {
1006         struct ifsregion *ifsp;
1007         struct strlist *sp;
1008         char *start;
1009         char *p;
1010         char *q;
1011         const char *ifs;
1012         const char *ifsspc;
1013         int had_param_ch = 0;
1014
1015         start = string;
1016
1017         if (ifslastp == NULL) {
1018                 /* Return entire argument, IFS doesn't apply to any of it */
1019                 sp = (struct strlist *)stalloc(sizeof *sp);
1020                 sp->text = start;
1021                 *arglist->lastp = sp;
1022                 arglist->lastp = &sp->next;
1023                 return;
1024         }
1025
1026         ifs = ifsset() ? ifsval() : " \t\n";
1027
1028         for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
1029                 p = string + ifsp->begoff;
1030                 while (p < string + ifsp->endoff) {
1031                         q = p;
1032                         if (*p == CTLESC)
1033                                 p++;
1034                         if (ifsp->inquotes) {
1035                                 /* Only NULs (should be from "$@") end args */
1036                                 had_param_ch = 1;
1037                                 if (*p != 0) {
1038                                         p++;
1039                                         continue;
1040                                 }
1041                                 ifsspc = NULL;
1042                         } else {
1043                                 if (!strchr(ifs, *p)) {
1044                                         had_param_ch = 1;
1045                                         p++;
1046                                         continue;
1047                                 }
1048                                 ifsspc = strchr(" \t\n", *p);
1049
1050                                 /* Ignore IFS whitespace at start */
1051                                 if (q == start && ifsspc != NULL) {
1052                                         p++;
1053                                         start = p;
1054                                         continue;
1055                                 }
1056                                 had_param_ch = 0;
1057                         }
1058
1059                         /* Save this argument... */
1060                         *q = '\0';
1061                         sp = (struct strlist *)stalloc(sizeof *sp);
1062                         sp->text = start;
1063                         *arglist->lastp = sp;
1064                         arglist->lastp = &sp->next;
1065                         p++;
1066
1067                         if (ifsspc != NULL) {
1068                                 /* Ignore further trailing IFS whitespace */
1069                                 for (; p < string + ifsp->endoff; p++) {
1070                                         q = p;
1071                                         if (*p == CTLESC)
1072                                                 p++;
1073                                         if (strchr(ifs, *p) == NULL) {
1074                                                 p = q;
1075                                                 break;
1076                                         }
1077                                         if (strchr(" \t\n", *p) == NULL) {
1078                                                 p++;
1079                                                 break;
1080                                         }
1081                                 }
1082                         }
1083                         start = p;
1084                 }
1085         }
1086
1087         /*
1088          * Save anything left as an argument.
1089          * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
1090          * generating 2 arguments, the second of which is empty.
1091          * Some recent clarification of the Posix spec say that it
1092          * should only generate one....
1093          */
1094         if (had_param_ch || *start != 0) {
1095                 sp = (struct strlist *)stalloc(sizeof *sp);
1096                 sp->text = start;
1097                 *arglist->lastp = sp;
1098                 arglist->lastp = &sp->next;
1099         }
1100 }
1101
1102
1103 static char expdir[PATH_MAX];
1104 #define expdir_end (expdir + sizeof(expdir))
1105
1106 /*
1107  * Perform pathname generation and remove control characters.
1108  * At this point, the only control characters should be CTLESC and CTLQUOTEMARK.
1109  * The results are stored in the list exparg.
1110  */
1111 static void
1112 expandmeta(struct strlist *str, int flag __unused)
1113 {
1114         char *p;
1115         struct strlist **savelastp;
1116         struct strlist *sp;
1117         char c;
1118         /* TODO - EXP_REDIR */
1119
1120         while (str) {
1121                 if (fflag)
1122                         goto nometa;
1123                 p = str->text;
1124                 for (;;) {                      /* fast check for meta chars */
1125                         if ((c = *p++) == '\0')
1126                                 goto nometa;
1127                         if (c == '*' || c == '?' || c == '[')
1128                                 break;
1129                 }
1130                 savelastp = exparg.lastp;
1131                 INTOFF;
1132                 expmeta(expdir, str->text);
1133                 INTON;
1134                 if (exparg.lastp == savelastp) {
1135                         /*
1136                          * no matches
1137                          */
1138 nometa:
1139                         *exparg.lastp = str;
1140                         rmescapes(str->text);
1141                         exparg.lastp = &str->next;
1142                 } else {
1143                         *exparg.lastp = NULL;
1144                         *savelastp = sp = expsort(*savelastp);
1145                         while (sp->next != NULL)
1146                                 sp = sp->next;
1147                         exparg.lastp = &sp->next;
1148                 }
1149                 str = str->next;
1150         }
1151 }
1152
1153
1154 /*
1155  * Do metacharacter (i.e. *, ?, [...]) expansion.
1156  */
1157
1158 static void
1159 expmeta(char *enddir, char *name)
1160 {
1161         const char *p;
1162         const char *q;
1163         const char *start;
1164         char *endname;
1165         int metaflag;
1166         struct stat statb;
1167         DIR *dirp;
1168         struct dirent *dp;
1169         int atend;
1170         int matchdot;
1171         int esc;
1172         int namlen;
1173
1174         metaflag = 0;
1175         start = name;
1176         for (p = name; esc = 0, *p; p += esc + 1) {
1177                 if (*p == '*' || *p == '?')
1178                         metaflag = 1;
1179                 else if (*p == '[') {
1180                         q = p + 1;
1181                         if (*q == '!' || *q == '^')
1182                                 q++;
1183                         for (;;) {
1184                                 while (*q == CTLQUOTEMARK)
1185                                         q++;
1186                                 if (*q == CTLESC)
1187                                         q++;
1188                                 if (*q == '/' || *q == '\0')
1189                                         break;
1190                                 if (*++q == ']') {
1191                                         metaflag = 1;
1192                                         break;
1193                                 }
1194                         }
1195                 } else if (*p == '\0')
1196                         break;
1197                 else if (*p == CTLQUOTEMARK)
1198                         continue;
1199                 else {
1200                         if (*p == CTLESC)
1201                                 esc++;
1202                         if (p[esc] == '/') {
1203                                 if (metaflag)
1204                                         break;
1205                                 start = p + esc + 1;
1206                         }
1207                 }
1208         }
1209         if (metaflag == 0) {    /* we've reached the end of the file name */
1210                 if (enddir != expdir)
1211                         metaflag++;
1212                 for (p = name ; ; p++) {
1213                         if (*p == CTLQUOTEMARK)
1214                                 continue;
1215                         if (*p == CTLESC)
1216                                 p++;
1217                         *enddir++ = *p;
1218                         if (*p == '\0')
1219                                 break;
1220                         if (enddir == expdir_end)
1221                                 return;
1222                 }
1223                 if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1224                         addfname(expdir);
1225                 return;
1226         }
1227         endname = name + (p - name);
1228         if (start != name) {
1229                 p = name;
1230                 while (p < start) {
1231                         while (*p == CTLQUOTEMARK)
1232                                 p++;
1233                         if (*p == CTLESC)
1234                                 p++;
1235                         *enddir++ = *p++;
1236                         if (enddir == expdir_end)
1237                                 return;
1238                 }
1239         }
1240         if (enddir == expdir) {
1241                 p = __DECONST(char *, ".");
1242         } else if (enddir == expdir + 1 && *expdir == '/') {
1243                 p = __DECONST(char *, "/");
1244         } else {
1245                 p = expdir;
1246                 enddir[-1] = '\0';
1247         }
1248         if ((dirp = opendir(p)) == NULL)
1249                 return;
1250         if (enddir != expdir)
1251                 enddir[-1] = '/';
1252         if (*endname == 0) {
1253                 atend = 1;
1254         } else {
1255                 atend = 0;
1256                 *endname = '\0';
1257                 endname += esc + 1;
1258         }
1259         matchdot = 0;
1260         p = start;
1261         while (*p == CTLQUOTEMARK)
1262                 p++;
1263         if (*p == CTLESC)
1264                 p++;
1265         if (*p == '.')
1266                 matchdot++;
1267         while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1268                 if (dp->d_name[0] == '.' && ! matchdot)
1269                         continue;
1270                 if (patmatch(start, dp->d_name, 0)) {
1271                         namlen = dp->d_namlen;
1272                         if (enddir + namlen + 1 > expdir_end)
1273                                 continue;
1274                         memcpy(enddir, dp->d_name, namlen + 1);
1275                         if (atend)
1276                                 addfname(expdir);
1277                         else {
1278                                 if (dp->d_type != DT_UNKNOWN &&
1279                                     dp->d_type != DT_DIR &&
1280                                     dp->d_type != DT_LNK)
1281                                         continue;
1282                                 if (enddir + namlen + 2 > expdir_end)
1283                                         continue;
1284                                 enddir[namlen] = '/';
1285                                 enddir[namlen + 1] = '\0';
1286                                 expmeta(enddir + namlen + 1, endname);
1287                         }
1288                 }
1289         }
1290         closedir(dirp);
1291         if (! atend)
1292                 endname[-esc - 1] = esc ? CTLESC : '/';
1293 }
1294
1295
1296 /*
1297  * Add a file name to the list.
1298  */
1299
1300 static void
1301 addfname(char *name)
1302 {
1303         char *p;
1304         struct strlist *sp;
1305
1306         p = stalloc(strlen(name) + 1);
1307         scopy(name, p);
1308         sp = (struct strlist *)stalloc(sizeof *sp);
1309         sp->text = p;
1310         *exparg.lastp = sp;
1311         exparg.lastp = &sp->next;
1312 }
1313
1314
1315 /*
1316  * Sort the results of file name expansion.  It calculates the number of
1317  * strings to sort and then calls msort (short for merge sort) to do the
1318  * work.
1319  */
1320
1321 static struct strlist *
1322 expsort(struct strlist *str)
1323 {
1324         int len;
1325         struct strlist *sp;
1326
1327         len = 0;
1328         for (sp = str ; sp ; sp = sp->next)
1329                 len++;
1330         return msort(str, len);
1331 }
1332
1333
1334 static struct strlist *
1335 msort(struct strlist *list, int len)
1336 {
1337         struct strlist *p, *q = NULL;
1338         struct strlist **lpp;
1339         int half;
1340         int n;
1341
1342         if (len <= 1)
1343                 return list;
1344         half = len >> 1;
1345         p = list;
1346         for (n = half ; --n >= 0 ; ) {
1347                 q = p;
1348                 p = p->next;
1349         }
1350         q->next = NULL;                 /* terminate first half of list */
1351         q = msort(list, half);          /* sort first half of list */
1352         p = msort(p, len - half);               /* sort second half */
1353         lpp = &list;
1354         for (;;) {
1355                 if (strcmp(p->text, q->text) < 0) {
1356                         *lpp = p;
1357                         lpp = &p->next;
1358                         if ((p = *lpp) == NULL) {
1359                                 *lpp = q;
1360                                 break;
1361                         }
1362                 } else {
1363                         *lpp = q;
1364                         lpp = &q->next;
1365                         if ((q = *lpp) == NULL) {
1366                                 *lpp = p;
1367                                 break;
1368                         }
1369                 }
1370         }
1371         return list;
1372 }
1373
1374
1375
1376 static wchar_t
1377 get_wc(const char **p)
1378 {
1379         wchar_t c;
1380         int chrlen;
1381
1382         chrlen = mbtowc(&c, *p, 4);
1383         if (chrlen == 0)
1384                 return 0;
1385         else if (chrlen == -1)
1386                 c = 0;
1387         else
1388                 *p += chrlen;
1389         return c;
1390 }
1391
1392
1393 /*
1394  * See if a character matches a character class, starting at the first colon
1395  * of "[:class:]".
1396  * If a valid character class is recognized, a pointer to the next character
1397  * after the final closing bracket is stored into *end, otherwise a null
1398  * pointer is stored into *end.
1399  */
1400 static int
1401 match_charclass(const char *p, wchar_t chr, const char **end)
1402 {
1403         char name[20];
1404         const char *nameend;
1405         wctype_t cclass;
1406
1407         *end = NULL;
1408         p++;
1409         nameend = strstr(p, ":]");
1410         if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
1411             nameend == p)
1412                 return 0;
1413         memcpy(name, p, nameend - p);
1414         name[nameend - p] = '\0';
1415         *end = nameend + 2;
1416         cclass = wctype(name);
1417         /* An unknown class matches nothing but is valid nevertheless. */
1418         if (cclass == 0)
1419                 return 0;
1420         return iswctype(chr, cclass);
1421 }
1422
1423
1424 /*
1425  * Returns true if the pattern matches the string.
1426  */
1427
1428 static int
1429 patmatch(const char *pattern, const char *string, int squoted)
1430 {
1431         const char *p, *q, *end;
1432         const char *bt_p, *bt_q;
1433         char c;
1434         wchar_t wc, wc2;
1435
1436         p = pattern;
1437         q = string;
1438         bt_p = NULL;
1439         bt_q = NULL;
1440         for (;;) {
1441                 switch (c = *p++) {
1442                 case '\0':
1443                         if (*q != '\0')
1444                                 goto backtrack;
1445                         return 1;
1446                 case CTLESC:
1447                         if (squoted && *q == CTLESC)
1448                                 q++;
1449                         if (*q++ != *p++)
1450                                 goto backtrack;
1451                         break;
1452                 case CTLQUOTEMARK:
1453                         continue;
1454                 case '?':
1455                         if (squoted && *q == CTLESC)
1456                                 q++;
1457                         if (*q == '\0')
1458                                 return 0;
1459                         if (localeisutf8) {
1460                                 wc = get_wc(&q);
1461                                 /*
1462                                  * A '?' does not match invalid UTF-8 but a
1463                                  * '*' does, so backtrack.
1464                                  */
1465                                 if (wc == 0)
1466                                         goto backtrack;
1467                         } else
1468                                 wc = (unsigned char)*q++;
1469                         break;
1470                 case '*':
1471                         c = *p;
1472                         while (c == CTLQUOTEMARK || c == '*')
1473                                 c = *++p;
1474                         /*
1475                          * If the pattern ends here, we know the string
1476                          * matches without needing to look at the rest of it.
1477                          */
1478                         if (c == '\0')
1479                                 return 1;
1480                         /*
1481                          * First try the shortest match for the '*' that
1482                          * could work. We can forget any earlier '*' since
1483                          * there is no way having it match more characters
1484                          * can help us, given that we are already here.
1485                          */
1486                         bt_p = p;
1487                         bt_q = q;
1488                         break;
1489                 case '[': {
1490                         const char *endp;
1491                         int invert, found;
1492                         wchar_t chr;
1493
1494                         endp = p;
1495                         if (*endp == '!' || *endp == '^')
1496                                 endp++;
1497                         for (;;) {
1498                                 while (*endp == CTLQUOTEMARK)
1499                                         endp++;
1500                                 if (*endp == 0)
1501                                         goto dft;               /* no matching ] */
1502                                 if (*endp == CTLESC)
1503                                         endp++;
1504                                 if (*++endp == ']')
1505                                         break;
1506                         }
1507                         invert = 0;
1508                         if (*p == '!' || *p == '^') {
1509                                 invert++;
1510                                 p++;
1511                         }
1512                         found = 0;
1513                         if (squoted && *q == CTLESC)
1514                                 q++;
1515                         if (*q == '\0')
1516                                 return 0;
1517                         if (localeisutf8) {
1518                                 chr = get_wc(&q);
1519                                 if (chr == 0)
1520                                         goto backtrack;
1521                         } else
1522                                 chr = (unsigned char)*q++;
1523                         c = *p++;
1524                         do {
1525                                 if (c == CTLQUOTEMARK)
1526                                         continue;
1527                                 if (c == '[' && *p == ':') {
1528                                         found |= match_charclass(p, chr, &end);
1529                                         if (end != NULL)
1530                                                 p = end;
1531                                 }
1532                                 if (c == CTLESC)
1533                                         c = *p++;
1534                                 if (localeisutf8 && c & 0x80) {
1535                                         p--;
1536                                         wc = get_wc(&p);
1537                                         if (wc == 0) /* bad utf-8 */
1538                                                 return 0;
1539                                 } else
1540                                         wc = (unsigned char)c;
1541                                 if (*p == '-' && p[1] != ']') {
1542                                         p++;
1543                                         while (*p == CTLQUOTEMARK)
1544                                                 p++;
1545                                         if (*p == CTLESC)
1546                                                 p++;
1547                                         if (localeisutf8) {
1548                                                 wc2 = get_wc(&p);
1549                                                 if (wc2 == 0) /* bad utf-8 */
1550                                                         return 0;
1551                                         } else
1552                                                 wc2 = (unsigned char)*p++;
1553                                         if (   collate_range_cmp(chr, wc) >= 0
1554                                             && collate_range_cmp(chr, wc2) <= 0
1555                                            )
1556                                                 found = 1;
1557                                 } else {
1558                                         if (chr == wc)
1559                                                 found = 1;
1560                                 }
1561                         } while ((c = *p++) != ']');
1562                         if (found == invert)
1563                                 goto backtrack;
1564                         break;
1565                 }
1566 dft:            default:
1567                         if (squoted && *q == CTLESC)
1568                                 q++;
1569                         if (*q == '\0')
1570                                 return 0;
1571                         if (*q++ == c)
1572                                 break;
1573 backtrack:
1574                         /*
1575                          * If we have a mismatch (other than hitting the end
1576                          * of the string), go back to the last '*' seen and
1577                          * have it match one additional character.
1578                          */
1579                         if (bt_p == NULL)
1580                                 return 0;
1581                         if (squoted && *bt_q == CTLESC)
1582                                 bt_q++;
1583                         if (*bt_q == '\0')
1584                                 return 0;
1585                         bt_q++;
1586                         p = bt_p;
1587                         q = bt_q;
1588                         break;
1589                 }
1590         }
1591 }
1592
1593
1594
1595 /*
1596  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1597  */
1598
1599 void
1600 rmescapes(char *str)
1601 {
1602         char *p, *q;
1603
1604         p = str;
1605         while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1606                 if (*p++ == '\0')
1607                         return;
1608         }
1609         q = p;
1610         while (*p) {
1611                 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1612                         p++;
1613                         continue;
1614                 }
1615                 if (*p == CTLESC)
1616                         p++;
1617                 *q++ = *p++;
1618         }
1619         *q = '\0';
1620 }
1621
1622
1623
1624 /*
1625  * See if a pattern matches in a case statement.
1626  */
1627
1628 int
1629 casematch(union node *pattern, const char *val)
1630 {
1631         struct stackmark smark;
1632         int result;
1633         char *p;
1634
1635         setstackmark(&smark);
1636         argbackq = pattern->narg.backquote;
1637         STARTSTACKSTR(expdest);
1638         ifslastp = NULL;
1639         argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1640         STPUTC('\0', expdest);
1641         p = grabstackstr(expdest);
1642         result = patmatch(p, val, 0);
1643         popstackmark(&smark);
1644         return result;
1645 }
1646
1647 /*
1648  * Our own itoa().
1649  */
1650
1651 static char *
1652 cvtnum(int num, char *buf)
1653 {
1654         char temp[32];
1655         int neg = num < 0;
1656         char *p = temp + 31;
1657
1658         temp[31] = '\0';
1659
1660         do {
1661                 *--p = num % 10 + '0';
1662         } while ((num /= 10) != 0);
1663
1664         if (neg)
1665                 *--p = '-';
1666
1667         STPUTS(p, buf);
1668         return buf;
1669 }
1670
1671 /*
1672  * Do most of the work for wordexp(3).
1673  */
1674
1675 int
1676 wordexpcmd(int argc, char **argv)
1677 {
1678         size_t len;
1679         int i;
1680
1681         out1fmt("%08x", argc - 1);
1682         for (i = 1, len = 0; i < argc; i++)
1683                 len += strlen(argv[i]);
1684         out1fmt("%08x", (int)len);
1685         for (i = 1; i < argc; i++)
1686                 outbin(argv[i], strlen(argv[i]) + 1, out1);
1687         return (0);
1688 }