sh - Sync to FreeBSD d038ee76 part 1/2
[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  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34
35 #ifndef lint
36 #if 0
37 static char sccsid[] = "@(#)expand.c    8.5 (Berkeley) 5/15/95";
38 #endif
39 #endif /* not lint */
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42
43 #include <sys/types.h>
44 #include <sys/time.h>
45 #include <sys/stat.h>
46 #include <dirent.h>
47 #include <errno.h>
48 #include <inttypes.h>
49 #include <limits.h>
50 #include <pwd.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <unistd.h>
55 #include <wchar.h>
56 #include <wctype.h>
57
58 /*
59  * Routines to expand arguments to commands.  We have to deal with
60  * backquotes, shell variables, and file metacharacters.
61  */
62
63 #include "shell.h"
64 #include "main.h"
65 #include "nodes.h"
66 #include "eval.h"
67 #include "expand.h"
68 #include "syntax.h"
69 #include "parser.h"
70 #include "jobs.h"
71 #include "options.h"
72 #include "var.h"
73 #include "input.h"
74 #include "output.h"
75 #include "memalloc.h"
76 #include "error.h"
77 #include "mystring.h"
78 #include "arith.h"
79 #include "show.h"
80 #include "builtins.h"
81
82 /*
83  * Structure specifying which parts of the string should be searched
84  * for IFS characters.
85  */
86
87 struct ifsregion {
88         struct ifsregion *next; /* next region in list */
89         int begoff;             /* offset of start of region */
90         int endoff;             /* offset of end of region */
91         int inquotes;           /* search for nul bytes only */
92 };
93
94
95 static char *expdest;                   /* output of current string */
96 static struct nodelist *argbackq;       /* list of back quote expressions */
97 static struct ifsregion ifsfirst;       /* first struct in list of ifs regions */
98 static struct ifsregion *ifslastp;      /* last struct in list */
99 static struct arglist exparg;           /* holds expanded arg list */
100
101 static char *argstr(char *, int);
102 static char *exptilde(char *, int);
103 static char *expari(char *);
104 static void expbackq(union node *, int, int);
105 static int subevalvar(char *, char *, int, int, int, int, int);
106 static char *evalvar(char *, int);
107 static int varisset(const char *, int);
108 static void strtodest(const char *, int, int, int);
109 static void varvalue(const char *, int, int, int);
110 static void recordregion(int, int, int);
111 static void removerecordregions(int);
112 static void ifsbreakup(char *, struct arglist *);
113 static void expandmeta(struct strlist *);
114 static void expmeta(char *, char *);
115 static void addfname(char *);
116 static struct strlist *expsort(struct strlist *);
117 static struct strlist *msort(struct strlist *, int);
118 static int patmatch(const char *, const char *, int);
119 static char *cvtnum(int, char *);
120 static int collate_range_cmp(wchar_t, wchar_t);
121
122 static int
123 collate_range_cmp(wchar_t c1, wchar_t c2)
124 {
125         static wchar_t s1[2], s2[2];
126
127         s1[0] = c1;
128         s2[0] = c2;
129         return (wcscoll(s1, s2));
130 }
131
132 static char *
133 stputs_quotes(const char *data, const char *syntax, char *p)
134 {
135         while (*data) {
136                 CHECKSTRSPACE(2, p);
137                 if (syntax[(int)*data] == CCTL)
138                         USTPUTC(CTLESC, p);
139                 USTPUTC(*data++, p);
140         }
141         return (p);
142 }
143 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
144
145 /*
146  * Perform expansions on an argument, placing the resulting list of arguments
147  * in arglist.  Parameter expansion, command substitution and arithmetic
148  * expansion are always performed; additional expansions can be requested
149  * via flag (EXP_*).
150  * The result is left in the stack string.
151  * When arglist is NULL, perform here document expansion.
152  *
153  * Caution: this function uses global state and is not reentrant.
154  * However, a new invocation after an interrupted invocation is safe
155  * and will reset the global state for the new call.
156  */
157 void
158 expandarg(union node *arg, struct arglist *arglist, int flag)
159 {
160         struct strlist *sp;
161         char *p;
162
163         argbackq = arg->narg.backquote;
164         STARTSTACKSTR(expdest);
165         ifsfirst.next = NULL;
166         ifslastp = NULL;
167         argstr(arg->narg.text, flag);
168         if (arglist == NULL) {
169                 STACKSTRNUL(expdest);
170                 return;                 /* here document expanded */
171         }
172         STPUTC('\0', expdest);
173         p = grabstackstr(expdest);
174         exparg.lastp = &exparg.list;
175         if (flag & EXP_FULL) {
176                 ifsbreakup(p, &exparg);
177                 *exparg.lastp = NULL;
178                 exparg.lastp = &exparg.list;
179                 expandmeta(exparg.list);
180         } else {
181                 sp = (struct strlist *)stalloc(sizeof (struct strlist));
182                 sp->text = p;
183                 *exparg.lastp = sp;
184                 exparg.lastp = &sp->next;
185         }
186         while (ifsfirst.next != NULL) {
187                 struct ifsregion *ifsp;
188                 INTOFF;
189                 ifsp = ifsfirst.next->next;
190                 ckfree(ifsfirst.next);
191                 ifsfirst.next = ifsp;
192                 INTON;
193         }
194         *exparg.lastp = NULL;
195         if (exparg.list) {
196                 *arglist->lastp = exparg.list;
197                 arglist->lastp = exparg.lastp;
198         }
199 }
200
201
202
203 /*
204  * Perform parameter expansion, command substitution and arithmetic
205  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
206  * Processing ends at a CTLENDVAR or CTLENDARI character as well as '\0'.
207  * This is used to expand word in ${var+word} etc.
208  * If EXP_FULL or EXP_CASE are set, keep and/or generate CTLESC
209  * characters to allow for further processing.
210  * If EXP_FULL is set, also preserve CTLQUOTEMARK characters.
211  */
212 static char *
213 argstr(char *p, int flag)
214 {
215         char c;
216         int quotes = flag & (EXP_FULL | EXP_CASE);      /* do CTLESC */
217         int firsteq = 1;
218         int split_lit;
219         int lit_quoted;
220
221         split_lit = flag & EXP_SPLIT_LIT;
222         lit_quoted = flag & EXP_LIT_QUOTED;
223         flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
224         if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
225                 p = exptilde(p, flag);
226         for (;;) {
227                 CHECKSTRSPACE(2, expdest);
228                 switch (c = *p++) {
229                 case '\0':
230                         return (p - 1);
231                 case CTLENDVAR:
232                 case CTLENDARI:
233                         return (p);
234                 case CTLQUOTEMARK:
235                         lit_quoted = 1;
236                         /* "$@" syntax adherence hack */
237                         if (p[0] == CTLVAR && p[2] == '@' && p[3] == '=')
238                                 break;
239                         if ((flag & EXP_FULL) != 0)
240                                 USTPUTC(c, expdest);
241                         break;
242                 case CTLQUOTEEND:
243                         lit_quoted = 0;
244                         break;
245                 case CTLESC:
246                         if (quotes)
247                                 USTPUTC(c, expdest);
248                         c = *p++;
249                         USTPUTC(c, expdest);
250                         if (split_lit && !lit_quoted)
251                                 recordregion(expdest - stackblock() -
252                                     (quotes ? 2 : 1),
253                                     expdest - stackblock(), 0);
254                         break;
255                 case CTLVAR:
256                         p = evalvar(p, flag);
257                         break;
258                 case CTLBACKQ:
259                 case CTLBACKQ|CTLQUOTE:
260                         expbackq(argbackq->n, c & CTLQUOTE, flag);
261                         argbackq = argbackq->next;
262                         break;
263                 case CTLARI:
264                         p = expari(p);
265                         break;
266                 case ':':
267                 case '=':
268                         /*
269                          * sort of a hack - expand tildes in variable
270                          * assignments (after the first '=' and after ':'s).
271                          */
272                         USTPUTC(c, expdest);
273                         if (split_lit && !lit_quoted)
274                                 recordregion(expdest - stackblock() - 1,
275                                     expdest - stackblock(), 0);
276                         if (flag & EXP_VARTILDE && *p == '~' &&
277                             (c != '=' || firsteq)) {
278                                 if (c == '=')
279                                         firsteq = 0;
280                                 p = exptilde(p, flag);
281                         }
282                         break;
283                 default:
284                         USTPUTC(c, expdest);
285                         if (split_lit && !lit_quoted)
286                                 recordregion(expdest - stackblock() - 1,
287                                     expdest - stackblock(), 0);
288                 }
289         }
290 }
291
292 /*
293  * Perform tilde expansion, placing the result in the stack string and
294  * returning the next position in the input string to process.
295  */
296 static char *
297 exptilde(char *p, int flag)
298 {
299         char c, *startp = p;
300         struct passwd *pw;
301         char *home;
302
303         for (;;) {
304                 c = *p;
305                 switch(c) {
306                 case CTLESC: /* This means CTL* are always considered quoted. */
307                 case CTLVAR:
308                 case CTLBACKQ:
309                 case CTLBACKQ | CTLQUOTE:
310                 case CTLARI:
311                 case CTLENDARI:
312                 case CTLQUOTEMARK:
313                         return (startp);
314                 case ':':
315                         if ((flag & EXP_VARTILDE) == 0)
316                         break;
317                         /* FALLTHROUGH */
318                 case '\0':
319                 case '/':
320                 case CTLENDVAR:
321         *p = '\0';
322         if (*(startp+1) == '\0') {
323                                 home = lookupvar("HOME");
324         } else {
325                                 pw = getpwnam(startp+1);
326                                 home = pw != NULL ? pw->pw_dir : NULL;
327         }
328         *p = c;
329                         if (home == NULL || *home == '\0')
330         return (startp);
331                         strtodest(home, flag, VSNORMAL, 1);
332                         return (p);
333                 }
334                 p++;
335         }
336 }
337
338
339 static void
340 removerecordregions(int endoff)
341 {
342         if (ifslastp == NULL)
343                 return;
344
345         if (ifsfirst.endoff > endoff) {
346                 while (ifsfirst.next != NULL) {
347                         struct ifsregion *ifsp;
348                         INTOFF;
349                         ifsp = ifsfirst.next->next;
350                         ckfree(ifsfirst.next);
351                         ifsfirst.next = ifsp;
352                         INTON;
353                 }
354                 if (ifsfirst.begoff > endoff)
355                         ifslastp = NULL;
356                 else {
357                         ifslastp = &ifsfirst;
358                         ifsfirst.endoff = endoff;
359                 }
360                 return;
361         }
362
363         ifslastp = &ifsfirst;
364         while (ifslastp->next && ifslastp->next->begoff < endoff)
365                 ifslastp=ifslastp->next;
366         while (ifslastp->next != NULL) {
367                 struct ifsregion *ifsp;
368                 INTOFF;
369                 ifsp = ifslastp->next->next;
370                 ckfree(ifslastp->next);
371                 ifslastp->next = ifsp;
372                 INTON;
373         }
374         if (ifslastp->endoff > endoff)
375                 ifslastp->endoff = endoff;
376 }
377
378 /*
379  * Expand arithmetic expression.
380  * Note that flag is not required as digits never require CTLESC characters.
381  */
382 static char *
383 expari(char *p)
384 {
385         char *q, *start;
386         arith_t result;
387         int begoff;
388         int quoted;
389         int adj;
390
391         quoted = *p++ == '"';
392         begoff = expdest - stackblock();
393         p = argstr(p, 0);
394         removerecordregions(begoff);
395         STPUTC('\0', expdest);
396         start = stackblock() + begoff;
397
398         q = grabstackstr(expdest);
399         result = arith(start);
400         ungrabstackstr(q, expdest);
401
402         start = stackblock() + begoff;
403         adj = start - expdest;
404         STADJUST(adj, expdest);
405
406         CHECKSTRSPACE((int)(DIGITS(result) + 1), expdest);
407         fmtstr(expdest, DIGITS(result), ARITH_FORMAT_STR, result);
408         adj = strlen(expdest);
409         STADJUST(adj, expdest);
410         if (!quoted)
411                 recordregion(begoff, expdest - stackblock(), 0);
412         return p;
413 }
414
415
416 /*
417  * Perform command substitution.
418  */
419 static void
420 expbackq(union node *cmd, int quoted, int flag)
421 {
422         struct backcmd in;
423         int i;
424         char buf[128];
425         char *p;
426         char *dest = expdest;
427         struct ifsregion saveifs, *savelastp;
428         struct nodelist *saveargbackq;
429         char lastc;
430         int startloc = dest - stackblock();
431         char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
432         int quotes = flag & (EXP_FULL | EXP_CASE);
433         size_t nnl;
434
435         INTOFF;
436         saveifs = ifsfirst;
437         savelastp = ifslastp;
438         saveargbackq = argbackq;
439         p = grabstackstr(dest);
440         evalbackcmd(cmd, &in);
441         ungrabstackstr(p, dest);
442         ifsfirst = saveifs;
443         ifslastp = savelastp;
444         argbackq = saveargbackq;
445
446         p = in.buf;
447         lastc = '\0';
448         nnl = 0;
449         /* Don't copy trailing newlines */
450         for (;;) {
451                 if (--in.nleft < 0) {
452                         if (in.fd < 0)
453                                 break;
454                         while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
455                         TRACE(("expbackq: read returns %d\n", i));
456                         if (i <= 0)
457                                 break;
458                         p = buf;
459                         in.nleft = i - 1;
460                 }
461                 lastc = *p++;
462                 if (lastc != '\0') {
463                         if (lastc == '\n') {
464                                 nnl++;
465                         } else {
466                                 CHECKSTRSPACE(nnl + 2, dest);
467                                 while (nnl > 0) {
468                                         nnl--;
469                                         USTPUTC('\n', dest);
470                                 }
471                                 if (quotes && syntax[(int)lastc] == CCTL)
472                                         USTPUTC(CTLESC, dest);
473                                 USTPUTC(lastc, dest);
474                         }
475                 }
476         }
477
478         if (in.fd >= 0)
479                 close(in.fd);
480         if (in.buf)
481                 ckfree(in.buf);
482         if (in.jp)
483                 exitstatus = waitforjob(in.jp, (int *)NULL);
484         if (quoted == 0)
485                 recordregion(startloc, dest - stackblock(), 0);
486         TRACE(("expbackq: size=%td: \"%.*s\"\n",
487                 ((dest - stackblock()) - startloc),
488                 (int)((dest - stackblock()) - startloc),
489                 stackblock() + startloc));
490         expdest = dest;
491         INTON;
492 }
493
494
495
496 static void
497 recordleft(const char *str, const char *loc, char *startp)
498 {
499         int amount;
500
501         amount = ((str - 1) - (loc - startp)) - expdest;
502         STADJUST(amount, expdest);
503         while (loc != str - 1)
504                 *startp++ = *loc++;
505 }
506
507 static int
508 subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
509   int varflags, int quotes)
510 {
511         char *startp;
512         char *loc = NULL;
513         char *q;
514         int c = 0;
515         struct nodelist *saveargbackq = argbackq;
516         int amount;
517
518         argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
519             subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ?
520             EXP_CASE : 0) | EXP_TILDE);
521         STACKSTRNUL(expdest);
522         argbackq = saveargbackq;
523         startp = stackblock() + startloc;
524         if (str == NULL)
525             str = stackblock() + strloc;
526
527         switch (subtype) {
528         case VSASSIGN:
529                 setvar(str, startp, 0);
530                 amount = startp - expdest;
531                 STADJUST(amount, expdest);
532                 varflags &= ~VSNUL;
533                 return 1;
534
535         case VSQUESTION:
536                 if (*p != CTLENDVAR) {
537                         outfmt(out2, "%s\n", startp);
538                         error((char *)NULL);
539                 }
540                 error("%.*s: parameter %snot set", (int)(p - str - 1),
541                       str, (varflags & VSNUL) ? "null or " : "");
542                 return 0;
543
544         case VSTRIMLEFT:
545                 for (loc = startp; loc < str; loc++) {
546                         c = *loc;
547                         *loc = '\0';
548                         if (patmatch(str, startp, quotes)) {
549                                 *loc = c;
550                                 recordleft(str, loc, startp);
551                                 return 1;
552                         }
553                         *loc = c;
554                         if (quotes && *loc == CTLESC)
555                                 loc++;
556                 }
557                 return 0;
558
559         case VSTRIMLEFTMAX:
560                 for (loc = str - 1; loc >= startp;) {
561                         c = *loc;
562                         *loc = '\0';
563                         if (patmatch(str, startp, quotes)) {
564                                 *loc = c;
565                                 recordleft(str, loc, startp);
566                                 return 1;
567                         }
568                         *loc = c;
569                         loc--;
570                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
571                                 for (q = startp; q < loc; q++)
572                                         if (*q == CTLESC)
573                                                 q++;
574                                 if (q > loc)
575                                         loc--;
576                         }
577                 }
578                 return 0;
579
580         case VSTRIMRIGHT:
581                 for (loc = str - 1; loc >= startp;) {
582                         if (patmatch(str, loc, quotes)) {
583                                 amount = loc - expdest;
584                                 STADJUST(amount, expdest);
585                                 return 1;
586                         }
587                         loc--;
588                         if (quotes && loc > startp && *(loc - 1) == CTLESC) {
589                                 for (q = startp; q < loc; q++)
590                                         if (*q == CTLESC)
591                                                 q++;
592                                 if (q > loc)
593                                         loc--;
594                         }
595                 }
596                 return 0;
597
598         case VSTRIMRIGHTMAX:
599                 for (loc = startp; loc < str - 1; loc++) {
600                         if (patmatch(str, loc, quotes)) {
601                                 amount = loc - expdest;
602                                 STADJUST(amount, expdest);
603                                 return 1;
604                         }
605                         if (quotes && *loc == CTLESC)
606                                 loc++;
607                 }
608                 return 0;
609
610
611         default:
612                 abort();
613         }
614 }
615
616
617 /*
618  * Expand a variable, and return a pointer to the next character in the
619  * input string.
620  */
621
622 static char *
623 evalvar(char *p, int flag)
624 {
625         int subtype;
626         int varflags;
627         char *var;
628         const char *val;
629         int patloc;
630         int c;
631         int set;
632         int special;
633         int startloc;
634         int varlen;
635         int varlenb;
636         int easy;
637         int quotes = flag & (EXP_FULL | EXP_CASE);
638         int record = 0;
639
640         varflags = (unsigned char)*p++;
641         subtype = varflags & VSTYPE;
642         var = p;
643         special = 0;
644         if (! is_name(*p))
645                 special = 1;
646         p = strchr(p, '=') + 1;
647 again: /* jump here after setting a variable with ${var=text} */
648         if (varflags & VSLINENO) {
649                 set = 1;
650                 special = 1;
651                 val = NULL;
652         } else if (special) {
653                 set = varisset(var, varflags & VSNUL);
654                 val = NULL;
655         } else {
656                 val = bltinlookup(var, 1);
657                 if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
658                         val = NULL;
659                         set = 0;
660                 } else
661                         set = 1;
662         }
663         varlen = 0;
664         startloc = expdest - stackblock();
665         if (!set && uflag && *var != '@' && *var != '*') {
666                 switch (subtype) {
667                 case VSNORMAL:
668                 case VSTRIMLEFT:
669                 case VSTRIMLEFTMAX:
670                 case VSTRIMRIGHT:
671                 case VSTRIMRIGHTMAX:
672                 case VSLENGTH:
673                         error("%.*s: parameter not set", (int)(p - var - 1),
674                             var);
675                 }
676         }
677         if (set && subtype != VSPLUS) {
678                 /* insert the value of the variable */
679                 if (special) {
680                         if (varflags & VSLINENO)
681                                 STPUTBIN(var, p - var - 1, expdest);
682                         else
683                         varvalue(var, varflags & VSQUOTE, subtype, flag);
684                         if (subtype == VSLENGTH) {
685                                 varlenb = expdest - stackblock() - startloc;
686                                 varlen = varlenb;
687                                 if (localeisutf8) {
688                                         val = stackblock() + startloc;
689                                         for (;val != expdest; val++)
690                                                 if ((*val & 0xC0) == 0x80)
691                                                         varlen--;
692                                 }
693                                 STADJUST(-varlenb, expdest);
694                         }
695                 } else {
696                         if (subtype == VSLENGTH) {
697                                 for (;*val; val++)
698                                         if (!localeisutf8 ||
699                                             (*val & 0xC0) != 0x80)
700                                                 varlen++;
701                         }
702                                 else
703                                 strtodest(val, flag, subtype,
704                                     varflags & VSQUOTE);
705                 }
706         }
707
708         if (subtype == VSPLUS)
709                 set = ! set;
710
711         easy = ((varflags & VSQUOTE) == 0 ||
712                 (*var == '@' && shellparam.nparam != 1));
713
714
715         switch (subtype) {
716         case VSLENGTH:
717                 expdest = cvtnum(varlen, expdest);
718                 record = 1;
719                 break;
720
721         case VSNORMAL:
722                 record = easy;
723                 break;
724
725         case VSPLUS:
726         case VSMINUS:
727                 if (!set) {
728                         argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
729                             (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
730                         break;
731                 }
732                 record = easy;
733                 break;
734
735         case VSTRIMLEFT:
736         case VSTRIMLEFTMAX:
737         case VSTRIMRIGHT:
738         case VSTRIMRIGHTMAX:
739                 if (!set)
740                         break;
741                 /*
742                  * Terminate the string and start recording the pattern
743                  * right after it
744                  */
745                 STPUTC('\0', expdest);
746                 patloc = expdest - stackblock();
747                 if (subevalvar(p, NULL, patloc, subtype,
748                     startloc, varflags, quotes) == 0) {
749                         int amount = (expdest - stackblock() - patloc) + 1;
750                         STADJUST(-amount, expdest);
751                 }
752                 /* Remove any recorded regions beyond start of variable */
753                 removerecordregions(startloc);
754                 record = 1;
755                 break;
756
757         case VSASSIGN:
758         case VSQUESTION:
759                 if (!set) {
760                         if (subevalvar(p, var, 0, subtype, startloc, varflags,
761                             quotes)) {
762                                 varflags &= ~VSNUL;
763                                 /*
764                                  * Remove any recorded regions beyond
765                                  * start of variable
766                                  */
767                                 removerecordregions(startloc);
768                                 goto again;
769                         }
770                         break;
771                 }
772                 record = easy;
773                 break;
774
775         case VSERROR:
776                 c = p - var - 1;
777                 error("${%.*s%s}: Bad substitution", c, var,
778                     (c > 0 && *p != CTLENDVAR) ? "..." : "");
779
780         default:
781                 abort();
782         }
783
784         if (record)
785                 recordregion(startloc, expdest - stackblock(),
786                     varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
787                     (*var == '@' || *var == '*')));
788
789         if (subtype != VSNORMAL) {      /* skip to end of alternative */
790                 int nesting = 1;
791                 for (;;) {
792                         if ((c = *p++) == CTLESC)
793                                 p++;
794                         else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
795                                 if (set)
796                                         argbackq = argbackq->next;
797                         } else if (c == CTLVAR) {
798                                 if ((*p++ & VSTYPE) != VSNORMAL)
799                                         nesting++;
800                         } else if (c == CTLENDVAR) {
801                                 if (--nesting == 0)
802                                         break;
803                         }
804                 }
805         }
806         return p;
807 }
808
809
810
811 /*
812  * Test whether a specialized variable is set.
813  */
814
815 static int
816 varisset(const char *name, int nulok)
817 {
818
819         if (*name == '!')
820                 return backgndpidset();
821         else if (*name == '@' || *name == '*') {
822                 if (*shellparam.p == NULL)
823                         return 0;
824
825                 if (nulok) {
826                         char **av;
827
828                         for (av = shellparam.p; *av; av++)
829                                 if (**av != '\0')
830                                         return 1;
831                         return 0;
832                 }
833         } else if (is_digit(*name)) {
834                 char *ap;
835                 long num;
836
837                 errno = 0;
838                 num = strtol(name, NULL, 10);
839                 if (errno != 0 || num > shellparam.nparam)
840                         return 0;
841
842                 if (num == 0)
843                         ap = arg0;
844                 else
845                         ap = shellparam.p[num - 1];
846
847                 if (nulok && (ap == NULL || *ap == '\0'))
848                         return 0;
849         }
850         return 1;
851 }
852
853 static void
854 strtodest(const char *p, int flag, int subtype, int quoted)
855 {
856         if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH)
857                 STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
858         else
859                 STPUTS(p, expdest);
860 }
861
862 /*
863  * Add the value of a specialized variable to the stack string.
864  */
865
866 static void
867 varvalue(const char *name, int quoted, int subtype, int flag)
868 {
869         int num;
870         char *p;
871         int i;
872         char sep[2];
873         char **ap;
874
875         switch (*name) {
876         case '$':
877                 num = rootpid;
878                 break;
879         case '?':
880                 num = oexitstatus;
881                 break;
882         case '#':
883                 num = shellparam.nparam;
884                 break;
885         case '!':
886                 num = backgndpidval();
887                 break;
888         case '-':
889                 for (i = 0 ; i < NOPTS ; i++) {
890                         if (optlist[i].val)
891                                 STPUTC(optlist[i].letter, expdest);
892                 }
893                 return;
894         case '@':
895                 if (flag & EXP_FULL && quoted) {
896                         for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
897                                 strtodest(p, flag, subtype, quoted);
898                                 if (*ap)
899                                         STPUTC('\0', expdest);
900                         }
901                         return;
902                 }
903                 /* FALLTHROUGH */
904         case '*':
905                 if (ifsset())
906                         sep[0] = ifsval()[0];
907                 else
908                         sep[0] = ' ';
909                 sep[1] = '\0';
910                 for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
911                         strtodest(p, flag, subtype, quoted);
912                         if (!*ap)
913                                 break;
914                         if (sep[0])
915                                 strtodest(sep, flag, subtype, quoted);
916                         else if (flag & EXP_FULL && !quoted && **ap != '\0')
917                                 STPUTC('\0', expdest);
918                 }
919                 return;
920         default:
921                 if (is_digit(*name)) {
922                         num = atoi(name);
923                         if (num == 0)
924                                 p = arg0;
925                         else if (num > 0 && num <= shellparam.nparam)
926                                 p = shellparam.p[num - 1];
927                         else
928                                 return;
929                                 strtodest(p, flag, subtype, quoted);
930                         }
931                 return;
932                 }
933         expdest = cvtnum(num, expdest);
934 }
935
936
937
938 /*
939  * Record the fact that we have to scan this region of the
940  * string for IFS characters.
941  */
942
943 static void
944 recordregion(int start, int end, int inquotes)
945 {
946         struct ifsregion *ifsp;
947
948         INTOFF;
949         if (ifslastp == NULL) {
950                 ifsp = &ifsfirst;
951         } else {
952                 if (ifslastp->endoff == start
953                     && ifslastp->inquotes == inquotes) {
954                         /* extend previous area */
955                         ifslastp->endoff = end;
956                         INTON;
957                         return;
958                 }
959                 ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
960                 ifslastp->next = ifsp;
961         }
962         ifslastp = ifsp;
963         ifslastp->next = NULL;
964         ifslastp->begoff = start;
965         ifslastp->endoff = end;
966         ifslastp->inquotes = inquotes;
967         INTON;
968 }
969
970
971
972 /*
973  * Break the argument string into pieces based upon IFS and add the
974  * strings to the argument list.  The regions of the string to be
975  * searched for IFS characters have been stored by recordregion.
976  * CTLESC characters are preserved but have little effect in this pass
977  * other than escaping CTL* characters.  In particular, they do not escape
978  * IFS characters: that should be done with the ifsregion mechanism.
979  * CTLQUOTEMARK characters are used to preserve empty quoted strings.
980  * This pass treats them as a regular character, making the string non-empty.
981  * Later, they are removed along with the other CTL* characters.
982  */
983 static void
984 ifsbreakup(char *string, struct arglist *arglist)
985 {
986         struct ifsregion *ifsp;
987         struct strlist *sp;
988         char *start;
989         char *p;
990         char *q;
991         const char *ifs;
992         const char *ifsspc;
993         int had_param_ch = 0;
994
995         start = string;
996
997         if (ifslastp == NULL) {
998                 /* Return entire argument, IFS doesn't apply to any of it */
999                 sp = (struct strlist *)stalloc(sizeof *sp);
1000                 sp->text = start;
1001                 *arglist->lastp = sp;
1002                 arglist->lastp = &sp->next;
1003                 return;
1004         }
1005
1006         ifs = ifsset() ? ifsval() : " \t\n";
1007
1008         for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
1009                 p = string + ifsp->begoff;
1010                 while (p < string + ifsp->endoff) {
1011                         q = p;
1012                         if (*p == CTLESC)
1013                                 p++;
1014                         if (ifsp->inquotes) {
1015                                 /* Only NULs (should be from "$@") end args */
1016                                 had_param_ch = 1;
1017                                 if (*p != 0) {
1018                                         p++;
1019                                         continue;
1020                                 }
1021                                 ifsspc = NULL;
1022                         } else {
1023                                 if (!strchr(ifs, *p)) {
1024                                         had_param_ch = 1;
1025                                         p++;
1026                                         continue;
1027                                 }
1028                                 ifsspc = strchr(" \t\n", *p);
1029
1030                                 /* Ignore IFS whitespace at start */
1031                                 if (q == start && ifsspc != NULL) {
1032                                         p++;
1033                                         start = p;
1034                                         continue;
1035                                 }
1036                                 had_param_ch = 0;
1037                         }
1038
1039                         /* Save this argument... */
1040                         *q = '\0';
1041                         sp = (struct strlist *)stalloc(sizeof *sp);
1042                         sp->text = start;
1043                         *arglist->lastp = sp;
1044                         arglist->lastp = &sp->next;
1045                         p++;
1046
1047                         if (ifsspc != NULL) {
1048                                 /* Ignore further trailing IFS whitespace */
1049                                 for (; p < string + ifsp->endoff; p++) {
1050                                         q = p;
1051                                         if (*p == CTLESC)
1052                                                 p++;
1053                                         if (strchr(ifs, *p) == NULL) {
1054                                                 p = q;
1055                                                 break;
1056                                         }
1057                                         if (strchr(" \t\n", *p) == NULL) {
1058                                                 p++;
1059                                                 break;
1060                                         }
1061                                 }
1062                         }
1063                         start = p;
1064                 }
1065         }
1066
1067         /*
1068          * Save anything left as an argument.
1069          * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
1070          * generating 2 arguments, the second of which is empty.
1071          * Some recent clarification of the Posix spec say that it
1072          * should only generate one....
1073          */
1074         if (had_param_ch || *start != 0) {
1075                 sp = (struct strlist *)stalloc(sizeof *sp);
1076                 sp->text = start;
1077                 *arglist->lastp = sp;
1078                 arglist->lastp = &sp->next;
1079         }
1080 }
1081
1082
1083 static char expdir[PATH_MAX];
1084 #define expdir_end (expdir + sizeof(expdir))
1085
1086 /*
1087  * Perform pathname generation and remove control characters.
1088  * At this point, the only control characters should be CTLESC and CTLQUOTEMARK.
1089  * The results are stored in the list exparg.
1090  */
1091 static void
1092 expandmeta(struct strlist *str)
1093 {
1094         char *p;
1095         struct strlist **savelastp;
1096         struct strlist *sp;
1097         char c;
1098
1099         while (str) {
1100                 savelastp = exparg.lastp;
1101                 if (!fflag) {
1102                         p = str->text;
1103                         for (; (c = *p) != '\0'; p++) {
1104                                 /* fast check for meta chars */
1105                                 if (c == '*' || c == '?' || c == '[') {
1106                 INTOFF;
1107                 expmeta(expdir, str->text);
1108                 INTON;
1109                                         break;
1110                                 }
1111                         }
1112                 }
1113                 if (exparg.lastp == savelastp) {
1114                         /*
1115                          * no matches
1116                          */
1117                         *exparg.lastp = str;
1118                         rmescapes(str->text);
1119                         exparg.lastp = &str->next;
1120                 } else {
1121                         *exparg.lastp = NULL;
1122                         *savelastp = sp = expsort(*savelastp);
1123                         while (sp->next != NULL)
1124                                 sp = sp->next;
1125                         exparg.lastp = &sp->next;
1126                 }
1127                 str = str->next;
1128         }
1129 }
1130
1131
1132 /*
1133  * Do metacharacter (i.e. *, ?, [...]) expansion.
1134  */
1135
1136 static void
1137 expmeta(char *enddir, char *name)
1138 {
1139         const char *p;
1140         const char *q;
1141         const char *start;
1142         char *endname;
1143         int metaflag;
1144         struct stat statb;
1145         DIR *dirp;
1146         struct dirent *dp;
1147         int atend;
1148         int matchdot;
1149         int esc;
1150         int namlen;
1151
1152         metaflag = 0;
1153         start = name;
1154         for (p = name; esc = 0, *p; p += esc + 1) {
1155                 if (*p == '*' || *p == '?')
1156                         metaflag = 1;
1157                 else if (*p == '[') {
1158                         q = p + 1;
1159                         if (*q == '!' || *q == '^')
1160                                 q++;
1161                         for (;;) {
1162                                 while (*q == CTLQUOTEMARK)
1163                                         q++;
1164                                 if (*q == CTLESC)
1165                                         q++;
1166                                 if (*q == '/' || *q == '\0')
1167                                         break;
1168                                 if (*++q == ']') {
1169                                         metaflag = 1;
1170                                         break;
1171                                 }
1172                         }
1173                 } else if (*p == '\0')
1174                         break;
1175                 else if (*p == CTLQUOTEMARK)
1176                         continue;
1177                 else {
1178                         if (*p == CTLESC)
1179                                 esc++;
1180                         if (p[esc] == '/') {
1181                                 if (metaflag)
1182                                         break;
1183                                 start = p + esc + 1;
1184                         }
1185                 }
1186         }
1187         if (metaflag == 0) {    /* we've reached the end of the file name */
1188                 if (enddir != expdir)
1189                         metaflag++;
1190                 for (p = name ; ; p++) {
1191                         if (*p == CTLQUOTEMARK)
1192                                 continue;
1193                         if (*p == CTLESC)
1194                                 p++;
1195                         *enddir++ = *p;
1196                         if (*p == '\0')
1197                                 break;
1198                         if (enddir == expdir_end)
1199                                 return;
1200                 }
1201                 if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1202                         addfname(expdir);
1203                 return;
1204         }
1205         endname = name + (p - name);
1206         if (start != name) {
1207                 p = name;
1208                 while (p < start) {
1209                         while (*p == CTLQUOTEMARK)
1210                                 p++;
1211                         if (*p == CTLESC)
1212                                 p++;
1213                         *enddir++ = *p++;
1214                         if (enddir == expdir_end)
1215                                 return;
1216                 }
1217         }
1218         if (enddir == expdir) {
1219                 p = ".";
1220         } else if (enddir == expdir + 1 && *expdir == '/') {
1221                 p = "/";
1222         } else {
1223                 p = expdir;
1224                 enddir[-1] = '\0';
1225         }
1226         if ((dirp = opendir(p)) == NULL)
1227                 return;
1228         if (enddir != expdir)
1229                 enddir[-1] = '/';
1230         if (*endname == 0) {
1231                 atend = 1;
1232         } else {
1233                 atend = 0;
1234                 *endname = '\0';
1235                 endname += esc + 1;
1236         }
1237         matchdot = 0;
1238         p = start;
1239         while (*p == CTLQUOTEMARK)
1240                 p++;
1241         if (*p == CTLESC)
1242                 p++;
1243         if (*p == '.')
1244                 matchdot++;
1245         while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1246                 if (dp->d_name[0] == '.' && ! matchdot)
1247                         continue;
1248                 if (patmatch(start, dp->d_name, 0)) {
1249                         namlen = dp->d_namlen;
1250                         if (enddir + namlen + 1 > expdir_end)
1251                                 continue;
1252                         memcpy(enddir, dp->d_name, namlen + 1);
1253                         if (atend)
1254                                 addfname(expdir);
1255                         else {
1256                                 if (dp->d_type != DT_UNKNOWN &&
1257                                     dp->d_type != DT_DIR &&
1258                                     dp->d_type != DT_LNK)
1259                                         continue;
1260                                 if (enddir + namlen + 2 > expdir_end)
1261                                         continue;
1262                                 enddir[namlen] = '/';
1263                                 enddir[namlen + 1] = '\0';
1264                                 expmeta(enddir + namlen + 1, endname);
1265                         }
1266                 }
1267         }
1268         closedir(dirp);
1269         if (! atend)
1270                 endname[-esc - 1] = esc ? CTLESC : '/';
1271 }
1272
1273
1274 /*
1275  * Add a file name to the list.
1276  */
1277
1278 static void
1279 addfname(char *name)
1280 {
1281         char *p;
1282         struct strlist *sp;
1283
1284         p = stsavestr(name);
1285         sp = (struct strlist *)stalloc(sizeof *sp);
1286         sp->text = p;
1287         *exparg.lastp = sp;
1288         exparg.lastp = &sp->next;
1289 }
1290
1291
1292 /*
1293  * Sort the results of file name expansion.  It calculates the number of
1294  * strings to sort and then calls msort (short for merge sort) to do the
1295  * work.
1296  */
1297
1298 static struct strlist *
1299 expsort(struct strlist *str)
1300 {
1301         int len;
1302         struct strlist *sp;
1303
1304         len = 0;
1305         for (sp = str ; sp ; sp = sp->next)
1306                 len++;
1307         return msort(str, len);
1308 }
1309
1310
1311 static struct strlist *
1312 msort(struct strlist *list, int len)
1313 {
1314         struct strlist *p, *q = NULL;
1315         struct strlist **lpp;
1316         int half;
1317         int n;
1318
1319         if (len <= 1)
1320                 return list;
1321         half = len >> 1;
1322         p = list;
1323         for (n = half ; --n >= 0 ; ) {
1324                 q = p;
1325                 p = p->next;
1326         }
1327         q->next = NULL;                 /* terminate first half of list */
1328         q = msort(list, half);          /* sort first half of list */
1329         p = msort(p, len - half);               /* sort second half */
1330         lpp = &list;
1331         for (;;) {
1332                 if (strcmp(p->text, q->text) < 0) {
1333                         *lpp = p;
1334                         lpp = &p->next;
1335                         if ((p = *lpp) == NULL) {
1336                                 *lpp = q;
1337                                 break;
1338                         }
1339                 } else {
1340                         *lpp = q;
1341                         lpp = &q->next;
1342                         if ((q = *lpp) == NULL) {
1343                                 *lpp = p;
1344                                 break;
1345                         }
1346                 }
1347         }
1348         return list;
1349 }
1350
1351
1352
1353 static wchar_t
1354 get_wc(const char **p)
1355 {
1356         wchar_t c;
1357         int chrlen;
1358
1359         chrlen = mbtowc(&c, *p, 4);
1360         if (chrlen == 0)
1361                 return 0;
1362         else if (chrlen == -1)
1363                 c = 0;
1364         else
1365                 *p += chrlen;
1366         return c;
1367 }
1368
1369
1370 /*
1371  * See if a character matches a character class, starting at the first colon
1372  * of "[:class:]".
1373  * If a valid character class is recognized, a pointer to the next character
1374  * after the final closing bracket is stored into *end, otherwise a null
1375  * pointer is stored into *end.
1376  */
1377 static int
1378 match_charclass(const char *p, wchar_t chr, const char **end)
1379 {
1380         char name[20];
1381         const char *nameend;
1382         wctype_t cclass;
1383
1384         *end = NULL;
1385         p++;
1386         nameend = strstr(p, ":]");
1387         if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
1388             nameend == p)
1389                 return 0;
1390         memcpy(name, p, nameend - p);
1391         name[nameend - p] = '\0';
1392         *end = nameend + 2;
1393         cclass = wctype(name);
1394         /* An unknown class matches nothing but is valid nevertheless. */
1395         if (cclass == 0)
1396                 return 0;
1397         return iswctype(chr, cclass);
1398 }
1399
1400
1401 /*
1402  * Returns true if the pattern matches the string.
1403  */
1404
1405 static int
1406 patmatch(const char *pattern, const char *string, int squoted)
1407 {
1408         const char *p, *q, *end;
1409         const char *bt_p, *bt_q;
1410         char c;
1411         wchar_t wc, wc2;
1412
1413         p = pattern;
1414         q = string;
1415         bt_p = NULL;
1416         bt_q = NULL;
1417         for (;;) {
1418                 switch (c = *p++) {
1419                 case '\0':
1420                         if (*q != '\0')
1421                                 goto backtrack;
1422                         return 1;
1423                 case CTLESC:
1424                         if (squoted && *q == CTLESC)
1425                                 q++;
1426                         if (*q++ != *p++)
1427                                 goto backtrack;
1428                         break;
1429                 case CTLQUOTEMARK:
1430                         continue;
1431                 case '?':
1432                         if (squoted && *q == CTLESC)
1433                                 q++;
1434                         if (*q == '\0')
1435                                 return 0;
1436                         if (localeisutf8) {
1437                                 wc = get_wc(&q);
1438                                 /*
1439                                  * A '?' does not match invalid UTF-8 but a
1440                                  * '*' does, so backtrack.
1441                                  */
1442                                 if (wc == 0)
1443                                         goto backtrack;
1444                         } else
1445                                 wc = (unsigned char)*q++;
1446                         break;
1447                 case '*':
1448                         c = *p;
1449                         while (c == CTLQUOTEMARK || c == '*')
1450                                 c = *++p;
1451                         /*
1452                          * If the pattern ends here, we know the string
1453                          * matches without needing to look at the rest of it.
1454                          */
1455                         if (c == '\0')
1456                                 return 1;
1457                         /*
1458                          * First try the shortest match for the '*' that
1459                          * could work. We can forget any earlier '*' since
1460                          * there is no way having it match more characters
1461                          * can help us, given that we are already here.
1462                          */
1463                         bt_p = p;
1464                         bt_q = q;
1465                         break;
1466                 case '[': {
1467                         const char *endp;
1468                         int invert, found;
1469                         wchar_t chr;
1470
1471                         endp = p;
1472                         if (*endp == '!' || *endp == '^')
1473                                 endp++;
1474                         do {
1475                                 while (*endp == CTLQUOTEMARK)
1476                                         endp++;
1477                                 if (*endp == 0)
1478                                         goto dft;               /* no matching ] */
1479                                 if (*endp == CTLESC)
1480                                         endp++;
1481                         } while (*++endp != ']');
1482                         invert = 0;
1483                         if (*p == '!' || *p == '^') {
1484                                 invert++;
1485                                 p++;
1486                         }
1487                         found = 0;
1488                         if (squoted && *q == CTLESC)
1489                                 q++;
1490                         if (*q == '\0')
1491                                 return 0;
1492                         if (localeisutf8) {
1493                                 chr = get_wc(&q);
1494                                 if (chr == 0)
1495                                         goto backtrack;
1496                         } else
1497                                 chr = (unsigned char)*q++;
1498                         c = *p++;
1499                         do {
1500                                 if (c == CTLQUOTEMARK)
1501                                         continue;
1502                                 if (c == '[' && *p == ':') {
1503                                         found |= match_charclass(p, chr, &end);
1504                                         if (end != NULL)
1505                                                 p = end;
1506                                 }
1507                                 if (c == CTLESC)
1508                                         c = *p++;
1509                                 if (localeisutf8 && c & 0x80) {
1510                                         p--;
1511                                         wc = get_wc(&p);
1512                                         if (wc == 0) /* bad utf-8 */
1513                                                 return 0;
1514                                 } else
1515                                         wc = (unsigned char)c;
1516                                 if (*p == '-' && p[1] != ']') {
1517                                         p++;
1518                                         while (*p == CTLQUOTEMARK)
1519                                                 p++;
1520                                         if (*p == CTLESC)
1521                                                 p++;
1522                                         if (localeisutf8) {
1523                                                 wc2 = get_wc(&p);
1524                                                 if (wc2 == 0) /* bad utf-8 */
1525                                                         return 0;
1526                                         } else
1527                                                 wc2 = (unsigned char)*p++;
1528                                         if (   collate_range_cmp(chr, wc) >= 0
1529                                             && collate_range_cmp(chr, wc2) <= 0
1530                                            )
1531                                                 found = 1;
1532                                 } else {
1533                                         if (chr == wc)
1534                                                 found = 1;
1535                                 }
1536                         } while ((c = *p++) != ']');
1537                         if (found == invert)
1538                                 goto backtrack;
1539                         break;
1540                 }
1541 dft:            default:
1542                         if (squoted && *q == CTLESC)
1543                                 q++;
1544                         if (*q == '\0')
1545                                 return 0;
1546                         if (*q++ == c)
1547                                 break;
1548 backtrack:
1549                         /*
1550                          * If we have a mismatch (other than hitting the end
1551                          * of the string), go back to the last '*' seen and
1552                          * have it match one additional character.
1553                          */
1554                         if (bt_p == NULL)
1555                                 return 0;
1556                         if (squoted && *bt_q == CTLESC)
1557                                 bt_q++;
1558                         if (*bt_q == '\0')
1559                                 return 0;
1560                         bt_q++;
1561                         p = bt_p;
1562                         q = bt_q;
1563                         break;
1564                 }
1565         }
1566 }
1567
1568
1569
1570 /*
1571  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1572  */
1573
1574 void
1575 rmescapes(char *str)
1576 {
1577         char *p, *q;
1578
1579         p = str;
1580         while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1581                 if (*p++ == '\0')
1582                         return;
1583         }
1584         q = p;
1585         while (*p) {
1586                 if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1587                         p++;
1588                         continue;
1589                 }
1590                 if (*p == CTLESC)
1591                         p++;
1592                 *q++ = *p++;
1593         }
1594         *q = '\0';
1595 }
1596
1597
1598
1599 /*
1600  * See if a pattern matches in a case statement.
1601  */
1602
1603 int
1604 casematch(union node *pattern, const char *val)
1605 {
1606         struct stackmark smark;
1607         int result;
1608         char *p;
1609
1610         setstackmark(&smark);
1611         argbackq = pattern->narg.backquote;
1612         STARTSTACKSTR(expdest);
1613         ifslastp = NULL;
1614         argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1615         STPUTC('\0', expdest);
1616         p = grabstackstr(expdest);
1617         result = patmatch(p, val, 0);
1618         popstackmark(&smark);
1619         return result;
1620 }
1621
1622 /*
1623  * Our own itoa().
1624  */
1625
1626 static char *
1627 cvtnum(int num, char *buf)
1628 {
1629         char temp[32];
1630         int neg = num < 0;
1631         char *p = temp + 31;
1632
1633         temp[31] = '\0';
1634
1635         do {
1636                 *--p = num % 10 + '0';
1637         } while ((num /= 10) != 0);
1638
1639         if (neg)
1640                 *--p = '-';
1641
1642         STPUTS(p, buf);
1643         return buf;
1644 }
1645
1646 /*
1647  * Do most of the work for wordexp(3).
1648  */
1649
1650 int
1651 wordexpcmd(int argc, char **argv)
1652 {
1653         size_t len;
1654         int i;
1655
1656         out1fmt("%08x", argc - 1);
1657         for (i = 1, len = 0; i < argc; i++)
1658                 len += strlen(argv[i]);
1659         out1fmt("%08x", (int)len);
1660         for (i = 1; i < argc; i++)
1661                 outbin(argv[i], strlen(argv[i]) + 1, out1);
1662         return (0);
1663 }