xref: /freebsd/bin/sh/expand.c (revision 669f9224ec5398fbc825dd031415126af032cf42)
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 
100 static char *argstr(char *, int);
101 static char *exptilde(char *, int);
102 static char *expari(char *);
103 static void expbackq(union node *, int, int);
104 static int subevalvar(char *, char *, int, int, int, int, int);
105 static char *evalvar(char *, int);
106 static int varisset(const char *, int);
107 static void strtodest(const char *, int, int, int);
108 static void varvalue(const char *, int, int, int);
109 static void recordregion(int, int, int);
110 static void removerecordregions(int);
111 static void ifsbreakup(char *, struct arglist *);
112 static void expandmeta(struct arglist *, struct arglist *);
113 static void expmeta(char *, char *, struct arglist *);
114 static int expsortcmp(const void *, const void *);
115 static int patmatch(const char *, const char *, int);
116 static char *cvtnum(int, char *);
117 static int collate_range_cmp(wchar_t, wchar_t);
118 
119 void
120 emptyarglist(struct arglist *list)
121 {
122 
123 	list->args = list->smallarg;
124 	list->count = 0;
125 	list->capacity = sizeof(list->smallarg) / sizeof(list->smallarg[0]);
126 }
127 
128 void
129 appendarglist(struct arglist *list, char *str)
130 {
131 	char **newargs;
132 	int newcapacity;
133 
134 	if (list->count >= list->capacity) {
135 		newcapacity = list->capacity * 2;
136 		if (newcapacity < 16)
137 			newcapacity = 16;
138 		if (newcapacity > INT_MAX / (int)sizeof(newargs[0]))
139 			error("Too many entries in arglist");
140 		newargs = stalloc(newcapacity * sizeof(newargs[0]));
141 		memcpy(newargs, list->args, list->count * sizeof(newargs[0]));
142 		list->args = newargs;
143 		list->capacity = newcapacity;
144 	}
145 	list->args[list->count++] = str;
146 }
147 
148 static int
149 collate_range_cmp(wchar_t c1, wchar_t c2)
150 {
151 	static wchar_t s1[2], s2[2];
152 
153 	s1[0] = c1;
154 	s2[0] = c2;
155 	return (wcscoll(s1, s2));
156 }
157 
158 static char *
159 stputs_quotes(const char *data, const char *syntax, char *p)
160 {
161 	while (*data) {
162 		CHECKSTRSPACE(2, p);
163 		if (syntax[(int)*data] == CCTL)
164 			USTPUTC(CTLESC, p);
165 		USTPUTC(*data++, p);
166 	}
167 	return (p);
168 }
169 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
170 
171 /*
172  * Perform expansions on an argument, placing the resulting list of arguments
173  * in arglist.  Parameter expansion, command substitution and arithmetic
174  * expansion are always performed; additional expansions can be requested
175  * via flag (EXP_*).
176  * The result is left in the stack string.
177  * When arglist is NULL, perform here document expansion.
178  *
179  * Caution: this function uses global state and is not reentrant.
180  * However, a new invocation after an interrupted invocation is safe
181  * and will reset the global state for the new call.
182  */
183 void
184 expandarg(union node *arg, struct arglist *arglist, int flag)
185 {
186 	struct arglist exparg;
187 	char *p;
188 
189 	argbackq = arg->narg.backquote;
190 	STARTSTACKSTR(expdest);
191 	ifsfirst.next = NULL;
192 	ifslastp = NULL;
193 	argstr(arg->narg.text, flag);
194 	if (arglist == NULL) {
195 		STACKSTRNUL(expdest);
196 		return;			/* here document expanded */
197 	}
198 	STPUTC('\0', expdest);
199 	p = grabstackstr(expdest);
200 	emptyarglist(&exparg);
201 	if (flag & EXP_FULL) {
202 		ifsbreakup(p, &exparg);
203 		expandmeta(&exparg, arglist);
204 	} else
205 		appendarglist(arglist, p);
206 	while (ifsfirst.next != NULL) {
207 		struct ifsregion *ifsp;
208 		INTOFF;
209 		ifsp = ifsfirst.next->next;
210 		ckfree(ifsfirst.next);
211 		ifsfirst.next = ifsp;
212 		INTON;
213 	}
214 }
215 
216 
217 
218 /*
219  * Perform parameter expansion, command substitution and arithmetic
220  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
221  * Processing ends at a CTLENDVAR or CTLENDARI character as well as '\0'.
222  * This is used to expand word in ${var+word} etc.
223  * If EXP_FULL or EXP_CASE are set, keep and/or generate CTLESC
224  * characters to allow for further processing.
225  * If EXP_FULL is set, also preserve CTLQUOTEMARK characters.
226  */
227 static char *
228 argstr(char *p, int flag)
229 {
230 	char c;
231 	int quotes = flag & (EXP_FULL | EXP_CASE);	/* do CTLESC */
232 	int firsteq = 1;
233 	int split_lit;
234 	int lit_quoted;
235 
236 	split_lit = flag & EXP_SPLIT_LIT;
237 	lit_quoted = flag & EXP_LIT_QUOTED;
238 	flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
239 	if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
240 		p = exptilde(p, flag);
241 	for (;;) {
242 		CHECKSTRSPACE(2, expdest);
243 		switch (c = *p++) {
244 		case '\0':
245 			return (p - 1);
246 		case CTLENDVAR:
247 		case CTLENDARI:
248 			return (p);
249 		case CTLQUOTEMARK:
250 			lit_quoted = 1;
251 			/* "$@" syntax adherence hack */
252 			if (p[0] == CTLVAR && (p[1] & VSQUOTE) != 0 &&
253 			    p[2] == '@' && p[3] == '=')
254 				break;
255 			if ((flag & EXP_FULL) != 0)
256 				USTPUTC(c, expdest);
257 			break;
258 		case CTLQUOTEEND:
259 			lit_quoted = 0;
260 			break;
261 		case CTLESC:
262 			if (quotes)
263 				USTPUTC(c, expdest);
264 			c = *p++;
265 			USTPUTC(c, expdest);
266 			if (split_lit && !lit_quoted)
267 				recordregion(expdest - stackblock() -
268 				    (quotes ? 2 : 1),
269 				    expdest - stackblock(), 0);
270 			break;
271 		case CTLVAR:
272 			p = evalvar(p, flag);
273 			break;
274 		case CTLBACKQ:
275 		case CTLBACKQ|CTLQUOTE:
276 			expbackq(argbackq->n, c & CTLQUOTE, flag);
277 			argbackq = argbackq->next;
278 			break;
279 		case CTLARI:
280 			p = expari(p);
281 			break;
282 		case ':':
283 		case '=':
284 			/*
285 			 * sort of a hack - expand tildes in variable
286 			 * assignments (after the first '=' and after ':'s).
287 			 */
288 			USTPUTC(c, expdest);
289 			if (split_lit && !lit_quoted)
290 				recordregion(expdest - stackblock() - 1,
291 				    expdest - stackblock(), 0);
292 			if (flag & EXP_VARTILDE && *p == '~' &&
293 			    (c != '=' || firsteq)) {
294 				if (c == '=')
295 					firsteq = 0;
296 				p = exptilde(p, flag);
297 			}
298 			break;
299 		default:
300 			USTPUTC(c, expdest);
301 			if (split_lit && !lit_quoted)
302 				recordregion(expdest - stackblock() - 1,
303 				    expdest - stackblock(), 0);
304 		}
305 	}
306 }
307 
308 /*
309  * Perform tilde expansion, placing the result in the stack string and
310  * returning the next position in the input string to process.
311  */
312 static char *
313 exptilde(char *p, int flag)
314 {
315 	char c, *startp = p;
316 	struct passwd *pw;
317 	char *home;
318 
319 	for (;;) {
320 		c = *p;
321 		switch(c) {
322 		case CTLESC: /* This means CTL* are always considered quoted. */
323 		case CTLVAR:
324 		case CTLBACKQ:
325 		case CTLBACKQ | CTLQUOTE:
326 		case CTLARI:
327 		case CTLENDARI:
328 		case CTLQUOTEMARK:
329 			return (startp);
330 		case ':':
331 			if ((flag & EXP_VARTILDE) == 0)
332 				break;
333 			/* FALLTHROUGH */
334 		case '\0':
335 		case '/':
336 		case CTLENDVAR:
337 			*p = '\0';
338 			if (*(startp+1) == '\0') {
339 				home = lookupvar("HOME");
340 			} else {
341 				pw = getpwnam(startp+1);
342 				home = pw != NULL ? pw->pw_dir : NULL;
343 			}
344 			*p = c;
345 			if (home == NULL || *home == '\0')
346 				return (startp);
347 			strtodest(home, flag, VSNORMAL, 1);
348 			return (p);
349 		}
350 		p++;
351 	}
352 }
353 
354 
355 static void
356 removerecordregions(int endoff)
357 {
358 	if (ifslastp == NULL)
359 		return;
360 
361 	if (ifsfirst.endoff > endoff) {
362 		while (ifsfirst.next != NULL) {
363 			struct ifsregion *ifsp;
364 			INTOFF;
365 			ifsp = ifsfirst.next->next;
366 			ckfree(ifsfirst.next);
367 			ifsfirst.next = ifsp;
368 			INTON;
369 		}
370 		if (ifsfirst.begoff > endoff)
371 			ifslastp = NULL;
372 		else {
373 			ifslastp = &ifsfirst;
374 			ifsfirst.endoff = endoff;
375 		}
376 		return;
377 	}
378 
379 	ifslastp = &ifsfirst;
380 	while (ifslastp->next && ifslastp->next->begoff < endoff)
381 		ifslastp=ifslastp->next;
382 	while (ifslastp->next != NULL) {
383 		struct ifsregion *ifsp;
384 		INTOFF;
385 		ifsp = ifslastp->next->next;
386 		ckfree(ifslastp->next);
387 		ifslastp->next = ifsp;
388 		INTON;
389 	}
390 	if (ifslastp->endoff > endoff)
391 		ifslastp->endoff = endoff;
392 }
393 
394 /*
395  * Expand arithmetic expression.
396  * Note that flag is not required as digits never require CTLESC characters.
397  */
398 static char *
399 expari(char *p)
400 {
401 	char *q, *start;
402 	arith_t result;
403 	int begoff;
404 	int quoted;
405 	int adj;
406 
407 	quoted = *p++ == '"';
408 	begoff = expdest - stackblock();
409 	p = argstr(p, 0);
410 	removerecordregions(begoff);
411 	STPUTC('\0', expdest);
412 	start = stackblock() + begoff;
413 
414 	q = grabstackstr(expdest);
415 	result = arith(start);
416 	ungrabstackstr(q, expdest);
417 
418 	start = stackblock() + begoff;
419 	adj = start - expdest;
420 	STADJUST(adj, expdest);
421 
422 	CHECKSTRSPACE((int)(DIGITS(result) + 1), expdest);
423 	fmtstr(expdest, DIGITS(result), ARITH_FORMAT_STR, result);
424 	adj = strlen(expdest);
425 	STADJUST(adj, expdest);
426 	if (!quoted)
427 		recordregion(begoff, expdest - stackblock(), 0);
428 	return p;
429 }
430 
431 
432 /*
433  * Perform command substitution.
434  */
435 static void
436 expbackq(union node *cmd, int quoted, int flag)
437 {
438 	struct backcmd in;
439 	int i;
440 	char buf[128];
441 	char *p;
442 	char *dest = expdest;
443 	struct ifsregion saveifs, *savelastp;
444 	struct nodelist *saveargbackq;
445 	char lastc;
446 	int startloc = dest - stackblock();
447 	char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
448 	int quotes = flag & (EXP_FULL | EXP_CASE);
449 	size_t nnl;
450 
451 	INTOFF;
452 	saveifs = ifsfirst;
453 	savelastp = ifslastp;
454 	saveargbackq = argbackq;
455 	p = grabstackstr(dest);
456 	evalbackcmd(cmd, &in);
457 	ungrabstackstr(p, dest);
458 	ifsfirst = saveifs;
459 	ifslastp = savelastp;
460 	argbackq = saveargbackq;
461 
462 	p = in.buf;
463 	lastc = '\0';
464 	nnl = 0;
465 	/* Don't copy trailing newlines */
466 	for (;;) {
467 		if (--in.nleft < 0) {
468 			if (in.fd < 0)
469 				break;
470 			while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR);
471 			TRACE(("expbackq: read returns %d\n", i));
472 			if (i <= 0)
473 				break;
474 			p = buf;
475 			in.nleft = i - 1;
476 		}
477 		lastc = *p++;
478 		if (lastc != '\0') {
479 			if (lastc == '\n') {
480 				nnl++;
481 			} else {
482 				CHECKSTRSPACE(nnl + 2, dest);
483 				while (nnl > 0) {
484 					nnl--;
485 					USTPUTC('\n', dest);
486 				}
487 				if (quotes && syntax[(int)lastc] == CCTL)
488 					USTPUTC(CTLESC, dest);
489 				USTPUTC(lastc, dest);
490 			}
491 		}
492 	}
493 
494 	if (in.fd >= 0)
495 		close(in.fd);
496 	if (in.buf)
497 		ckfree(in.buf);
498 	if (in.jp)
499 		exitstatus = waitforjob(in.jp, (int *)NULL);
500 	if (quoted == 0)
501 		recordregion(startloc, dest - stackblock(), 0);
502 	TRACE(("expbackq: size=%td: \"%.*s\"\n",
503 		((dest - stackblock()) - startloc),
504 		(int)((dest - stackblock()) - startloc),
505 		stackblock() + startloc));
506 	expdest = dest;
507 	INTON;
508 }
509 
510 
511 
512 static void
513 recordleft(const char *str, const char *loc, char *startp)
514 {
515 	int amount;
516 
517 	amount = ((str - 1) - (loc - startp)) - expdest;
518 	STADJUST(amount, expdest);
519 	while (loc != str - 1)
520 		*startp++ = *loc++;
521 }
522 
523 static int
524 subevalvar(char *p, char *str, int strloc, int subtype, int startloc,
525   int varflags, int quotes)
526 {
527 	char *startp;
528 	char *loc = NULL;
529 	char *q;
530 	int c = 0;
531 	struct nodelist *saveargbackq = argbackq;
532 	int amount;
533 
534 	argstr(p, (subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
535 	    subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX ?
536 	    EXP_CASE : 0) | EXP_TILDE);
537 	STACKSTRNUL(expdest);
538 	argbackq = saveargbackq;
539 	startp = stackblock() + startloc;
540 	if (str == NULL)
541 	    str = stackblock() + strloc;
542 
543 	switch (subtype) {
544 	case VSASSIGN:
545 		setvar(str, startp, 0);
546 		amount = startp - expdest;
547 		STADJUST(amount, expdest);
548 		varflags &= ~VSNUL;
549 		return 1;
550 
551 	case VSQUESTION:
552 		if (*p != CTLENDVAR) {
553 			outfmt(out2, "%s\n", startp);
554 			error((char *)NULL);
555 		}
556 		error("%.*s: parameter %snot set", (int)(p - str - 1),
557 		      str, (varflags & VSNUL) ? "null or " : "");
558 		return 0;
559 
560 	case VSTRIMLEFT:
561 		for (loc = startp; loc < str; loc++) {
562 			c = *loc;
563 			*loc = '\0';
564 			if (patmatch(str, startp, quotes)) {
565 				*loc = c;
566 				recordleft(str, loc, startp);
567 				return 1;
568 			}
569 			*loc = c;
570 			if (quotes && *loc == CTLESC)
571 				loc++;
572 		}
573 		return 0;
574 
575 	case VSTRIMLEFTMAX:
576 		for (loc = str - 1; loc >= startp;) {
577 			c = *loc;
578 			*loc = '\0';
579 			if (patmatch(str, startp, quotes)) {
580 				*loc = c;
581 				recordleft(str, loc, startp);
582 				return 1;
583 			}
584 			*loc = c;
585 			loc--;
586 			if (quotes && loc > startp && *(loc - 1) == CTLESC) {
587 				for (q = startp; q < loc; q++)
588 					if (*q == CTLESC)
589 						q++;
590 				if (q > loc)
591 					loc--;
592 			}
593 		}
594 		return 0;
595 
596 	case VSTRIMRIGHT:
597 		for (loc = str - 1; loc >= startp;) {
598 			if (patmatch(str, loc, quotes)) {
599 				amount = loc - expdest;
600 				STADJUST(amount, expdest);
601 				return 1;
602 			}
603 			loc--;
604 			if (quotes && loc > startp && *(loc - 1) == CTLESC) {
605 				for (q = startp; q < loc; q++)
606 					if (*q == CTLESC)
607 						q++;
608 				if (q > loc)
609 					loc--;
610 			}
611 		}
612 		return 0;
613 
614 	case VSTRIMRIGHTMAX:
615 		for (loc = startp; loc < str - 1; loc++) {
616 			if (patmatch(str, loc, quotes)) {
617 				amount = loc - expdest;
618 				STADJUST(amount, expdest);
619 				return 1;
620 			}
621 			if (quotes && *loc == CTLESC)
622 				loc++;
623 		}
624 		return 0;
625 
626 
627 	default:
628 		abort();
629 	}
630 }
631 
632 
633 /*
634  * Expand a variable, and return a pointer to the next character in the
635  * input string.
636  */
637 
638 static char *
639 evalvar(char *p, int flag)
640 {
641 	int subtype;
642 	int varflags;
643 	char *var;
644 	const char *val;
645 	int patloc;
646 	int c;
647 	int set;
648 	int special;
649 	int startloc;
650 	int varlen;
651 	int varlenb;
652 	int easy;
653 	int quotes = flag & (EXP_FULL | EXP_CASE);
654 	int record = 0;
655 
656 	varflags = (unsigned char)*p++;
657 	subtype = varflags & VSTYPE;
658 	var = p;
659 	special = 0;
660 	if (! is_name(*p))
661 		special = 1;
662 	p = strchr(p, '=') + 1;
663 again: /* jump here after setting a variable with ${var=text} */
664 	if (varflags & VSLINENO) {
665 		set = 1;
666 		special = 1;
667 		val = NULL;
668 	} else if (special) {
669 		set = varisset(var, varflags & VSNUL);
670 		val = NULL;
671 	} else {
672 		val = bltinlookup(var, 1);
673 		if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
674 			val = NULL;
675 			set = 0;
676 		} else
677 			set = 1;
678 	}
679 	varlen = 0;
680 	startloc = expdest - stackblock();
681 	if (!set && uflag && *var != '@' && *var != '*') {
682 		switch (subtype) {
683 		case VSNORMAL:
684 		case VSTRIMLEFT:
685 		case VSTRIMLEFTMAX:
686 		case VSTRIMRIGHT:
687 		case VSTRIMRIGHTMAX:
688 		case VSLENGTH:
689 			error("%.*s: parameter not set", (int)(p - var - 1),
690 			    var);
691 		}
692 	}
693 	if (set && subtype != VSPLUS) {
694 		/* insert the value of the variable */
695 		if (special) {
696 			if (varflags & VSLINENO)
697 				STPUTBIN(var, p - var - 1, expdest);
698 			else
699 				varvalue(var, varflags & VSQUOTE, subtype, flag);
700 			if (subtype == VSLENGTH) {
701 				varlenb = expdest - stackblock() - startloc;
702 				varlen = varlenb;
703 				if (localeisutf8) {
704 					val = stackblock() + startloc;
705 					for (;val != expdest; val++)
706 						if ((*val & 0xC0) == 0x80)
707 							varlen--;
708 				}
709 				STADJUST(-varlenb, expdest);
710 			}
711 		} else {
712 			if (subtype == VSLENGTH) {
713 				for (;*val; val++)
714 					if (!localeisutf8 ||
715 					    (*val & 0xC0) != 0x80)
716 						varlen++;
717 			}
718 			else
719 				strtodest(val, flag, subtype,
720 				    varflags & VSQUOTE);
721 		}
722 	}
723 
724 	if (subtype == VSPLUS)
725 		set = ! set;
726 
727 	easy = ((varflags & VSQUOTE) == 0 ||
728 		(*var == '@' && shellparam.nparam != 1));
729 
730 
731 	switch (subtype) {
732 	case VSLENGTH:
733 		expdest = cvtnum(varlen, expdest);
734 		record = 1;
735 		break;
736 
737 	case VSNORMAL:
738 		record = easy;
739 		break;
740 
741 	case VSPLUS:
742 	case VSMINUS:
743 		if (!set) {
744 			argstr(p, flag | (flag & EXP_FULL ? EXP_SPLIT_LIT : 0) |
745 			    (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0));
746 			break;
747 		}
748 		record = easy;
749 		break;
750 
751 	case VSTRIMLEFT:
752 	case VSTRIMLEFTMAX:
753 	case VSTRIMRIGHT:
754 	case VSTRIMRIGHTMAX:
755 		if (!set)
756 			break;
757 		/*
758 		 * Terminate the string and start recording the pattern
759 		 * right after it
760 		 */
761 		STPUTC('\0', expdest);
762 		patloc = expdest - stackblock();
763 		if (subevalvar(p, NULL, patloc, subtype,
764 		    startloc, varflags, quotes) == 0) {
765 			int amount = (expdest - stackblock() - patloc) + 1;
766 			STADJUST(-amount, expdest);
767 		}
768 		/* Remove any recorded regions beyond start of variable */
769 		removerecordregions(startloc);
770 		record = 1;
771 		break;
772 
773 	case VSASSIGN:
774 	case VSQUESTION:
775 		if (!set) {
776 			if (subevalvar(p, var, 0, subtype, startloc, varflags,
777 			    quotes)) {
778 				varflags &= ~VSNUL;
779 				/*
780 				 * Remove any recorded regions beyond
781 				 * start of variable
782 				 */
783 				removerecordregions(startloc);
784 				goto again;
785 			}
786 			break;
787 		}
788 		record = easy;
789 		break;
790 
791 	case VSERROR:
792 		c = p - var - 1;
793 		error("${%.*s%s}: Bad substitution", c, var,
794 		    (c > 0 && *p != CTLENDVAR) ? "..." : "");
795 
796 	default:
797 		abort();
798 	}
799 
800 	if (record)
801 		recordregion(startloc, expdest - stackblock(),
802 		    varflags & VSQUOTE || (ifsset() && ifsval()[0] == '\0' &&
803 		    (*var == '@' || *var == '*')));
804 
805 	if (subtype != VSNORMAL) {	/* skip to end of alternative */
806 		int nesting = 1;
807 		for (;;) {
808 			if ((c = *p++) == CTLESC)
809 				p++;
810 			else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE)) {
811 				if (set)
812 					argbackq = argbackq->next;
813 			} else if (c == CTLVAR) {
814 				if ((*p++ & VSTYPE) != VSNORMAL)
815 					nesting++;
816 			} else if (c == CTLENDVAR) {
817 				if (--nesting == 0)
818 					break;
819 			}
820 		}
821 	}
822 	return p;
823 }
824 
825 
826 
827 /*
828  * Test whether a specialized variable is set.
829  */
830 
831 static int
832 varisset(const char *name, int nulok)
833 {
834 
835 	if (*name == '!')
836 		return backgndpidset();
837 	else if (*name == '@' || *name == '*') {
838 		if (*shellparam.p == NULL)
839 			return 0;
840 
841 		if (nulok) {
842 			char **av;
843 
844 			for (av = shellparam.p; *av; av++)
845 				if (**av != '\0')
846 					return 1;
847 			return 0;
848 		}
849 	} else if (is_digit(*name)) {
850 		char *ap;
851 		long num;
852 
853 		errno = 0;
854 		num = strtol(name, NULL, 10);
855 		if (errno != 0 || num > shellparam.nparam)
856 			return 0;
857 
858 		if (num == 0)
859 			ap = arg0;
860 		else
861 			ap = shellparam.p[num - 1];
862 
863 		if (nulok && (ap == NULL || *ap == '\0'))
864 			return 0;
865 	}
866 	return 1;
867 }
868 
869 static void
870 strtodest(const char *p, int flag, int subtype, int quoted)
871 {
872 	if (flag & (EXP_FULL | EXP_CASE) && subtype != VSLENGTH)
873 		STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
874 	else
875 		STPUTS(p, expdest);
876 }
877 
878 /*
879  * Add the value of a specialized variable to the stack string.
880  */
881 
882 static void
883 varvalue(const char *name, int quoted, int subtype, int flag)
884 {
885 	int num;
886 	char *p;
887 	int i;
888 	char sep[2];
889 	char **ap;
890 
891 	switch (*name) {
892 	case '$':
893 		num = rootpid;
894 		break;
895 	case '?':
896 		num = oexitstatus;
897 		break;
898 	case '#':
899 		num = shellparam.nparam;
900 		break;
901 	case '!':
902 		num = backgndpidval();
903 		break;
904 	case '-':
905 		for (i = 0 ; i < NSHORTOPTS ; i++) {
906 			if (optlist[i].val)
907 				STPUTC(optlist[i].letter, expdest);
908 		}
909 		return;
910 	case '@':
911 		if (flag & EXP_FULL && quoted) {
912 			for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
913 				strtodest(p, flag, subtype, quoted);
914 				if (*ap)
915 					STPUTC('\0', expdest);
916 			}
917 			return;
918 		}
919 		/* FALLTHROUGH */
920 	case '*':
921 		if (ifsset())
922 			sep[0] = ifsval()[0];
923 		else
924 			sep[0] = ' ';
925 		sep[1] = '\0';
926 		for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
927 			strtodest(p, flag, subtype, quoted);
928 			if (!*ap)
929 				break;
930 			if (sep[0])
931 				strtodest(sep, flag, subtype, quoted);
932 			else if (flag & EXP_FULL && !quoted && **ap != '\0')
933 				STPUTC('\0', expdest);
934 		}
935 		return;
936 	default:
937 		if (is_digit(*name)) {
938 			num = atoi(name);
939 			if (num == 0)
940 				p = arg0;
941 			else if (num > 0 && num <= shellparam.nparam)
942 				p = shellparam.p[num - 1];
943 			else
944 				return;
945 			strtodest(p, flag, subtype, quoted);
946 		}
947 		return;
948 	}
949 	expdest = cvtnum(num, expdest);
950 }
951 
952 
953 
954 /*
955  * Record the fact that we have to scan this region of the
956  * string for IFS characters.
957  */
958 
959 static void
960 recordregion(int start, int end, int inquotes)
961 {
962 	struct ifsregion *ifsp;
963 
964 	INTOFF;
965 	if (ifslastp == NULL) {
966 		ifsp = &ifsfirst;
967 	} else {
968 		if (ifslastp->endoff == start
969 		    && ifslastp->inquotes == inquotes) {
970 			/* extend previous area */
971 			ifslastp->endoff = end;
972 			INTON;
973 			return;
974 		}
975 		ifsp = (struct ifsregion *)ckmalloc(sizeof (struct ifsregion));
976 		ifslastp->next = ifsp;
977 	}
978 	ifslastp = ifsp;
979 	ifslastp->next = NULL;
980 	ifslastp->begoff = start;
981 	ifslastp->endoff = end;
982 	ifslastp->inquotes = inquotes;
983 	INTON;
984 }
985 
986 
987 
988 /*
989  * Break the argument string into pieces based upon IFS and add the
990  * strings to the argument list.  The regions of the string to be
991  * searched for IFS characters have been stored by recordregion.
992  * CTLESC characters are preserved but have little effect in this pass
993  * other than escaping CTL* characters.  In particular, they do not escape
994  * IFS characters: that should be done with the ifsregion mechanism.
995  * CTLQUOTEMARK characters are used to preserve empty quoted strings.
996  * This pass treats them as a regular character, making the string non-empty.
997  * Later, they are removed along with the other CTL* characters.
998  */
999 static void
1000 ifsbreakup(char *string, struct arglist *arglist)
1001 {
1002 	struct ifsregion *ifsp;
1003 	char *start;
1004 	char *p;
1005 	char *q;
1006 	const char *ifs;
1007 	const char *ifsspc;
1008 	int had_param_ch = 0;
1009 
1010 	start = string;
1011 
1012 	if (ifslastp == NULL) {
1013 		/* Return entire argument, IFS doesn't apply to any of it */
1014 		appendarglist(arglist, start);
1015 		return;
1016 	}
1017 
1018 	ifs = ifsset() ? ifsval() : " \t\n";
1019 
1020 	for (ifsp = &ifsfirst; ifsp != NULL; ifsp = ifsp->next) {
1021 		p = string + ifsp->begoff;
1022 		while (p < string + ifsp->endoff) {
1023 			q = p;
1024 			if (*p == CTLESC)
1025 				p++;
1026 			if (ifsp->inquotes) {
1027 				/* Only NULs (should be from "$@") end args */
1028 				had_param_ch = 1;
1029 				if (*p != 0) {
1030 					p++;
1031 					continue;
1032 				}
1033 				ifsspc = NULL;
1034 			} else {
1035 				if (!strchr(ifs, *p)) {
1036 					had_param_ch = 1;
1037 					p++;
1038 					continue;
1039 				}
1040 				ifsspc = strchr(" \t\n", *p);
1041 
1042 				/* Ignore IFS whitespace at start */
1043 				if (q == start && ifsspc != NULL) {
1044 					p++;
1045 					start = p;
1046 					continue;
1047 				}
1048 				had_param_ch = 0;
1049 			}
1050 
1051 			/* Save this argument... */
1052 			*q = '\0';
1053 			appendarglist(arglist, start);
1054 			p++;
1055 
1056 			if (ifsspc != NULL) {
1057 				/* Ignore further trailing IFS whitespace */
1058 				for (; p < string + ifsp->endoff; p++) {
1059 					q = p;
1060 					if (*p == CTLESC)
1061 						p++;
1062 					if (strchr(ifs, *p) == NULL) {
1063 						p = q;
1064 						break;
1065 					}
1066 					if (strchr(" \t\n", *p) == NULL) {
1067 						p++;
1068 						break;
1069 					}
1070 				}
1071 			}
1072 			start = p;
1073 		}
1074 	}
1075 
1076 	/*
1077 	 * Save anything left as an argument.
1078 	 * Traditionally we have treated 'IFS=':'; set -- x$IFS' as
1079 	 * generating 2 arguments, the second of which is empty.
1080 	 * Some recent clarification of the Posix spec say that it
1081 	 * should only generate one....
1082 	 */
1083 	if (had_param_ch || *start != 0)
1084 		appendarglist(arglist, start);
1085 }
1086 
1087 
1088 static char expdir[PATH_MAX];
1089 #define expdir_end (expdir + sizeof(expdir))
1090 
1091 /*
1092  * Perform pathname generation and remove control characters.
1093  * At this point, the only control characters should be CTLESC and CTLQUOTEMARK.
1094  * The results are stored in the list dstlist.
1095  */
1096 static void
1097 expandmeta(struct arglist *srclist, struct arglist *dstlist)
1098 {
1099 	char *p;
1100 	int firstmatch;
1101 	int i;
1102 	char c;
1103 
1104 	for (i = 0; i < srclist->count; i++) {
1105 		firstmatch = dstlist->count;
1106 		if (!fflag) {
1107 			p = srclist->args[i];
1108 			for (; (c = *p) != '\0'; p++) {
1109 				/* fast check for meta chars */
1110 				if (c == '*' || c == '?' || c == '[') {
1111 					INTOFF;
1112 					expmeta(expdir, srclist->args[i],
1113 					    dstlist);
1114 					INTON;
1115 					break;
1116 				}
1117 			}
1118 		}
1119 		if (dstlist->count == firstmatch) {
1120 			/*
1121 			 * no matches
1122 			 */
1123 			rmescapes(srclist->args[i]);
1124 			appendarglist(dstlist, srclist->args[i]);
1125 		} else {
1126 			qsort(&dstlist->args[firstmatch],
1127 			    dstlist->count - firstmatch,
1128 			    sizeof(dstlist->args[0]), expsortcmp);
1129 		}
1130 	}
1131 }
1132 
1133 
1134 /*
1135  * Do metacharacter (i.e. *, ?, [...]) expansion.
1136  */
1137 
1138 static void
1139 expmeta(char *enddir, char *name, struct arglist *arglist)
1140 {
1141 	const char *p;
1142 	const char *q;
1143 	const char *start;
1144 	char *endname;
1145 	int metaflag;
1146 	struct stat statb;
1147 	DIR *dirp;
1148 	struct dirent *dp;
1149 	int atend;
1150 	int matchdot;
1151 	int esc;
1152 	int namlen;
1153 
1154 	metaflag = 0;
1155 	start = name;
1156 	for (p = name; esc = 0, *p; p += esc + 1) {
1157 		if (*p == '*' || *p == '?')
1158 			metaflag = 1;
1159 		else if (*p == '[') {
1160 			q = p + 1;
1161 			if (*q == '!' || *q == '^')
1162 				q++;
1163 			for (;;) {
1164 				while (*q == CTLQUOTEMARK)
1165 					q++;
1166 				if (*q == CTLESC)
1167 					q++;
1168 				if (*q == '/' || *q == '\0')
1169 					break;
1170 				if (*++q == ']') {
1171 					metaflag = 1;
1172 					break;
1173 				}
1174 			}
1175 		} else if (*p == '\0')
1176 			break;
1177 		else if (*p == CTLQUOTEMARK)
1178 			continue;
1179 		else {
1180 			if (*p == CTLESC)
1181 				esc++;
1182 			if (p[esc] == '/') {
1183 				if (metaflag)
1184 					break;
1185 				start = p + esc + 1;
1186 			}
1187 		}
1188 	}
1189 	if (metaflag == 0) {	/* we've reached the end of the file name */
1190 		if (enddir != expdir)
1191 			metaflag++;
1192 		for (p = name ; ; p++) {
1193 			if (*p == CTLQUOTEMARK)
1194 				continue;
1195 			if (*p == CTLESC)
1196 				p++;
1197 			*enddir++ = *p;
1198 			if (*p == '\0')
1199 				break;
1200 			if (enddir == expdir_end)
1201 				return;
1202 		}
1203 		if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1204 			appendarglist(arglist, stsavestr(expdir));
1205 		return;
1206 	}
1207 	endname = name + (p - name);
1208 	if (start != name) {
1209 		p = name;
1210 		while (p < start) {
1211 			while (*p == CTLQUOTEMARK)
1212 				p++;
1213 			if (*p == CTLESC)
1214 				p++;
1215 			*enddir++ = *p++;
1216 			if (enddir == expdir_end)
1217 				return;
1218 		}
1219 	}
1220 	if (enddir == expdir) {
1221 		p = ".";
1222 	} else if (enddir == expdir + 1 && *expdir == '/') {
1223 		p = "/";
1224 	} else {
1225 		p = expdir;
1226 		enddir[-1] = '\0';
1227 	}
1228 	if ((dirp = opendir(p)) == NULL)
1229 		return;
1230 	if (enddir != expdir)
1231 		enddir[-1] = '/';
1232 	if (*endname == 0) {
1233 		atend = 1;
1234 	} else {
1235 		atend = 0;
1236 		*endname = '\0';
1237 		endname += esc + 1;
1238 	}
1239 	matchdot = 0;
1240 	p = start;
1241 	while (*p == CTLQUOTEMARK)
1242 		p++;
1243 	if (*p == CTLESC)
1244 		p++;
1245 	if (*p == '.')
1246 		matchdot++;
1247 	while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1248 		if (dp->d_name[0] == '.' && ! matchdot)
1249 			continue;
1250 		if (patmatch(start, dp->d_name, 0)) {
1251 			namlen = dp->d_namlen;
1252 			if (enddir + namlen + 1 > expdir_end)
1253 				continue;
1254 			memcpy(enddir, dp->d_name, namlen + 1);
1255 			if (atend)
1256 				appendarglist(arglist, stsavestr(expdir));
1257 			else {
1258 				if (dp->d_type != DT_UNKNOWN &&
1259 				    dp->d_type != DT_DIR &&
1260 				    dp->d_type != DT_LNK)
1261 					continue;
1262 				if (enddir + namlen + 2 > expdir_end)
1263 					continue;
1264 				enddir[namlen] = '/';
1265 				enddir[namlen + 1] = '\0';
1266 				expmeta(enddir + namlen + 1, endname, arglist);
1267 			}
1268 		}
1269 	}
1270 	closedir(dirp);
1271 	if (! atend)
1272 		endname[-esc - 1] = esc ? CTLESC : '/';
1273 }
1274 
1275 
1276 static int
1277 expsortcmp(const void *p1, const void *p2)
1278 {
1279 	const char *s1 = *(const char * const *)p1;
1280 	const char *s2 = *(const char * const *)p2;
1281 
1282 	return (strcmp(s1, s2));
1283 }
1284 
1285 
1286 
1287 static wchar_t
1288 get_wc(const char **p)
1289 {
1290 	wchar_t c;
1291 	int chrlen;
1292 
1293 	chrlen = mbtowc(&c, *p, 4);
1294 	if (chrlen == 0)
1295 		return 0;
1296 	else if (chrlen == -1)
1297 		c = 0;
1298 	else
1299 		*p += chrlen;
1300 	return c;
1301 }
1302 
1303 
1304 /*
1305  * See if a character matches a character class, starting at the first colon
1306  * of "[:class:]".
1307  * If a valid character class is recognized, a pointer to the next character
1308  * after the final closing bracket is stored into *end, otherwise a null
1309  * pointer is stored into *end.
1310  */
1311 static int
1312 match_charclass(const char *p, wchar_t chr, const char **end)
1313 {
1314 	char name[20];
1315 	const char *nameend;
1316 	wctype_t cclass;
1317 
1318 	*end = NULL;
1319 	p++;
1320 	nameend = strstr(p, ":]");
1321 	if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
1322 	    nameend == p)
1323 		return 0;
1324 	memcpy(name, p, nameend - p);
1325 	name[nameend - p] = '\0';
1326 	*end = nameend + 2;
1327 	cclass = wctype(name);
1328 	/* An unknown class matches nothing but is valid nevertheless. */
1329 	if (cclass == 0)
1330 		return 0;
1331 	return iswctype(chr, cclass);
1332 }
1333 
1334 
1335 /*
1336  * Returns true if the pattern matches the string.
1337  */
1338 
1339 static int
1340 patmatch(const char *pattern, const char *string, int squoted)
1341 {
1342 	const char *p, *q, *end;
1343 	const char *bt_p, *bt_q;
1344 	char c;
1345 	wchar_t wc, wc2;
1346 
1347 	p = pattern;
1348 	q = string;
1349 	bt_p = NULL;
1350 	bt_q = NULL;
1351 	for (;;) {
1352 		switch (c = *p++) {
1353 		case '\0':
1354 			if (*q != '\0')
1355 				goto backtrack;
1356 			return 1;
1357 		case CTLESC:
1358 			if (squoted && *q == CTLESC)
1359 				q++;
1360 			if (*q++ != *p++)
1361 				goto backtrack;
1362 			break;
1363 		case CTLQUOTEMARK:
1364 			continue;
1365 		case '?':
1366 			if (squoted && *q == CTLESC)
1367 				q++;
1368 			if (*q == '\0')
1369 				return 0;
1370 			if (localeisutf8) {
1371 				wc = get_wc(&q);
1372 				/*
1373 				 * A '?' does not match invalid UTF-8 but a
1374 				 * '*' does, so backtrack.
1375 				 */
1376 				if (wc == 0)
1377 					goto backtrack;
1378 			} else
1379 				wc = (unsigned char)*q++;
1380 			break;
1381 		case '*':
1382 			c = *p;
1383 			while (c == CTLQUOTEMARK || c == '*')
1384 				c = *++p;
1385 			/*
1386 			 * If the pattern ends here, we know the string
1387 			 * matches without needing to look at the rest of it.
1388 			 */
1389 			if (c == '\0')
1390 				return 1;
1391 			/*
1392 			 * First try the shortest match for the '*' that
1393 			 * could work. We can forget any earlier '*' since
1394 			 * there is no way having it match more characters
1395 			 * can help us, given that we are already here.
1396 			 */
1397 			bt_p = p;
1398 			bt_q = q;
1399 			break;
1400 		case '[': {
1401 			const char *savep, *saveq;
1402 			int invert, found;
1403 			wchar_t chr;
1404 
1405 			savep = p, saveq = q;
1406 			invert = 0;
1407 			if (*p == '!' || *p == '^') {
1408 				invert++;
1409 				p++;
1410 			}
1411 			found = 0;
1412 			if (squoted && *q == CTLESC)
1413 				q++;
1414 			if (*q == '\0')
1415 				return 0;
1416 			if (localeisutf8) {
1417 				chr = get_wc(&q);
1418 				if (chr == 0)
1419 					goto backtrack;
1420 			} else
1421 				chr = (unsigned char)*q++;
1422 			c = *p++;
1423 			do {
1424 				if (c == '\0') {
1425 					p = savep, q = saveq;
1426 					c = '[';
1427 					goto dft;
1428 				}
1429 				if (c == CTLQUOTEMARK)
1430 					continue;
1431 				if (c == '[' && *p == ':') {
1432 					found |= match_charclass(p, chr, &end);
1433 					if (end != NULL)
1434 						p = end;
1435 				}
1436 				if (c == CTLESC)
1437 					c = *p++;
1438 				if (localeisutf8 && c & 0x80) {
1439 					p--;
1440 					wc = get_wc(&p);
1441 					if (wc == 0) /* bad utf-8 */
1442 						return 0;
1443 				} else
1444 					wc = (unsigned char)c;
1445 				if (*p == '-' && p[1] != ']') {
1446 					p++;
1447 					while (*p == CTLQUOTEMARK)
1448 						p++;
1449 					if (*p == CTLESC)
1450 						p++;
1451 					if (localeisutf8) {
1452 						wc2 = get_wc(&p);
1453 						if (wc2 == 0) /* bad utf-8 */
1454 							return 0;
1455 					} else
1456 						wc2 = (unsigned char)*p++;
1457 					if (   collate_range_cmp(chr, wc) >= 0
1458 					    && collate_range_cmp(chr, wc2) <= 0
1459 					   )
1460 						found = 1;
1461 				} else {
1462 					if (chr == wc)
1463 						found = 1;
1464 				}
1465 			} while ((c = *p++) != ']');
1466 			if (found == invert)
1467 				goto backtrack;
1468 			break;
1469 		}
1470 dft:	        default:
1471 			if (squoted && *q == CTLESC)
1472 				q++;
1473 			if (*q == '\0')
1474 				return 0;
1475 			if (*q++ == c)
1476 				break;
1477 backtrack:
1478 			/*
1479 			 * If we have a mismatch (other than hitting the end
1480 			 * of the string), go back to the last '*' seen and
1481 			 * have it match one additional character.
1482 			 */
1483 			if (bt_p == NULL)
1484 				return 0;
1485 			if (squoted && *bt_q == CTLESC)
1486 				bt_q++;
1487 			if (*bt_q == '\0')
1488 				return 0;
1489 			bt_q++;
1490 			p = bt_p;
1491 			q = bt_q;
1492 			break;
1493 		}
1494 	}
1495 }
1496 
1497 
1498 
1499 /*
1500  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1501  */
1502 
1503 void
1504 rmescapes(char *str)
1505 {
1506 	char *p, *q;
1507 
1508 	p = str;
1509 	while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1510 		if (*p++ == '\0')
1511 			return;
1512 	}
1513 	q = p;
1514 	while (*p) {
1515 		if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1516 			p++;
1517 			continue;
1518 		}
1519 		if (*p == CTLESC)
1520 			p++;
1521 		*q++ = *p++;
1522 	}
1523 	*q = '\0';
1524 }
1525 
1526 
1527 
1528 /*
1529  * See if a pattern matches in a case statement.
1530  */
1531 
1532 int
1533 casematch(union node *pattern, const char *val)
1534 {
1535 	struct stackmark smark;
1536 	int result;
1537 	char *p;
1538 
1539 	setstackmark(&smark);
1540 	argbackq = pattern->narg.backquote;
1541 	STARTSTACKSTR(expdest);
1542 	ifslastp = NULL;
1543 	argstr(pattern->narg.text, EXP_TILDE | EXP_CASE);
1544 	STPUTC('\0', expdest);
1545 	p = grabstackstr(expdest);
1546 	result = patmatch(p, val, 0);
1547 	popstackmark(&smark);
1548 	return result;
1549 }
1550 
1551 /*
1552  * Our own itoa().
1553  */
1554 
1555 static char *
1556 cvtnum(int num, char *buf)
1557 {
1558 	char temp[32];
1559 	int neg = num < 0;
1560 	char *p = temp + 31;
1561 
1562 	temp[31] = '\0';
1563 
1564 	do {
1565 		*--p = num % 10 + '0';
1566 	} while ((num /= 10) != 0);
1567 
1568 	if (neg)
1569 		*--p = '-';
1570 
1571 	STPUTS(p, buf);
1572 	return buf;
1573 }
1574 
1575 /*
1576  * Do most of the work for wordexp(3).
1577  */
1578 
1579 int
1580 wordexpcmd(int argc, char **argv)
1581 {
1582 	size_t len;
1583 	int i;
1584 
1585 	out1fmt("%08x", argc - 1);
1586 	for (i = 1, len = 0; i < argc; i++)
1587 		len += strlen(argv[i]);
1588 	out1fmt("%08x", (int)len);
1589 	for (i = 1; i < argc; i++)
1590 		outbin(argv[i], strlen(argv[i]) + 1, out1);
1591         return (0);
1592 }
1593 
1594 /*
1595  * Do most of the work for wordexp(3), new version.
1596  */
1597 
1598 int
1599 freebsd_wordexpcmd(int argc __unused, char **argv __unused)
1600 {
1601 	struct arglist arglist;
1602 	union node *args, *n;
1603 	size_t len;
1604 	int ch;
1605 	int protected = 0;
1606 	int fd = -1;
1607 	int i;
1608 
1609 	while ((ch = nextopt("f:p")) != '\0') {
1610 		switch (ch) {
1611 		case 'f':
1612 			fd = number(shoptarg);
1613 			break;
1614 		case 'p':
1615 			protected = 1;
1616 			break;
1617 		}
1618 	}
1619 	if (*argptr != NULL)
1620 		error("wrong number of arguments");
1621 	if (fd < 0)
1622 		error("missing fd");
1623 	INTOFF;
1624 	setinputfd(fd, 1);
1625 	INTON;
1626 	args = parsewordexp();
1627 	popfile(); /* will also close fd */
1628 	if (protected)
1629 		for (n = args; n != NULL; n = n->narg.next) {
1630 			if (n->narg.backquote != NULL) {
1631 				outcslow('C', out1);
1632 				error("command substitution disabled");
1633 			}
1634 		}
1635 	outcslow(' ', out1);
1636 	emptyarglist(&arglist);
1637 	for (n = args; n != NULL; n = n->narg.next)
1638 		expandarg(n, &arglist, EXP_FULL | EXP_TILDE);
1639 	for (i = 0, len = 0; i < arglist.count; i++)
1640 		len += strlen(arglist.args[i]);
1641 	out1fmt("%016x %016zx", arglist.count, len);
1642 	for (i = 0; i < arglist.count; i++)
1643 		outbin(arglist.args[i], strlen(arglist.args[i]) + 1, out1);
1644 	return (0);
1645 }
1646