xref: /src/bin/sh/expand.c (revision 632c73b4bfd48b89b7c2318079fd50835b8b5016)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1991, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 1997-2005
7  *	Herbert Xu <herbert@gondor.apana.org.au>.  All rights reserved.
8  * Copyright (c) 2010-2015
9  *	Jilles Tjoelker <jilles@stack.nl>.  All rights reserved.
10  *
11  * This code is derived from software contributed to Berkeley by
12  * Kenneth Almquist.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/types.h>
40 #include <sys/time.h>
41 #include <sys/stat.h>
42 #include <dirent.h>
43 #include <errno.h>
44 #include <inttypes.h>
45 #include <limits.h>
46 #include <pwd.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51 #include <wchar.h>
52 #include <wctype.h>
53 
54 /*
55  * Routines to expand arguments to commands.  We have to deal with
56  * backquotes, shell variables, and file metacharacters.
57  */
58 
59 #include "shell.h"
60 #include "main.h"
61 #include "nodes.h"
62 #include "eval.h"
63 #include "expand.h"
64 #include "syntax.h"
65 #include "parser.h"
66 #include "jobs.h"
67 #include "options.h"
68 #include "var.h"
69 #include "input.h"
70 #include "output.h"
71 #include "memalloc.h"
72 #include "error.h"
73 #include "mystring.h"
74 #include "arith.h"
75 #include "show.h"
76 #include "builtins.h"
77 
78 enum wordstate { WORD_IDLE, WORD_WS_DELIMITED, WORD_QUOTEMARK };
79 
80 struct worddest {
81 	struct arglist *list;
82 	enum wordstate state;
83 };
84 
85 static char *expdest;			/* output of current string */
86 
87 static const char *argstr(const char *, struct nodelist **restrict, int,
88     struct worddest *);
89 static const char *exptilde(const char *, int);
90 static const char *expari(const char *, struct nodelist **restrict, int,
91     struct worddest *);
92 static void expbackq(union node *, int, int, struct worddest *);
93 static const char *subevalvar_trim(const char *, struct nodelist **restrict,
94     int, int, int);
95 static const char *subevalvar_misc(const char *, struct nodelist **restrict,
96     const char *, int, int, int);
97 static const char *evalvar(const char *, struct nodelist **restrict, int,
98     struct worddest *);
99 static int varisset(const char *, int);
100 static void strtodest(const char *, int, int, int, struct worddest *);
101 static void reprocess(int, int, int, int, struct worddest *);
102 static void varvalue(const char *, int, int, int, struct worddest *);
103 static void expandmeta(char *, struct arglist *);
104 static void expmeta(char *, char *, struct arglist *);
105 static int expsortcmp(const void *, const void *);
106 static int patmatch(const char *, const char *);
107 static void cvtnum(int, char *);
108 static int collate_range_cmp(wchar_t, wchar_t);
109 
110 void
emptyarglist(struct arglist * list)111 emptyarglist(struct arglist *list)
112 {
113 
114 	list->args = list->smallarg;
115 	list->count = 0;
116 	list->capacity = sizeof(list->smallarg) / sizeof(list->smallarg[0]);
117 }
118 
119 void
appendarglist(struct arglist * list,char * str)120 appendarglist(struct arglist *list, char *str)
121 {
122 	char **newargs;
123 	int newcapacity;
124 
125 	if (list->count >= list->capacity) {
126 		newcapacity = list->capacity * 2;
127 		if (newcapacity < 16)
128 			newcapacity = 16;
129 		if (newcapacity > INT_MAX / (int)sizeof(newargs[0]))
130 			error("Too many entries in arglist");
131 		newargs = stalloc(newcapacity * sizeof(newargs[0]));
132 		memcpy(newargs, list->args, list->count * sizeof(newargs[0]));
133 		list->args = newargs;
134 		list->capacity = newcapacity;
135 	}
136 	list->args[list->count++] = str;
137 }
138 
139 static int
collate_range_cmp(wchar_t c1,wchar_t c2)140 collate_range_cmp(wchar_t c1, wchar_t c2)
141 {
142 	wchar_t s1[2], s2[2];
143 
144 	s1[0] = c1;
145 	s1[1] = L'\0';
146 	s2[0] = c2;
147 	s2[1] = L'\0';
148 	return (wcscoll(s1, s2));
149 }
150 
151 static char *
stputs_quotes(const char * data,const char * syntax,char * p)152 stputs_quotes(const char *data, const char *syntax, char *p)
153 {
154 	while (*data) {
155 		CHECKSTRSPACE(2, p);
156 		if (syntax[(int)*data] == CCTL)
157 			USTPUTC(CTLESC, p);
158 		USTPUTC(*data++, p);
159 	}
160 	return (p);
161 }
162 #define STPUTS_QUOTES(data, syntax, p) p = stputs_quotes((data), syntax, p)
163 
164 static char *
nextword(char c,int flag,char * p,struct worddest * dst)165 nextword(char c, int flag, char *p, struct worddest *dst)
166 {
167 	int is_ws;
168 
169 	is_ws = c == '\t' || c == '\n' || c == ' ';
170 	if (p != stackblock() || (is_ws ? dst->state == WORD_QUOTEMARK :
171 	    dst->state != WORD_WS_DELIMITED) || c == '\0') {
172 		STPUTC('\0', p);
173 		if (flag & EXP_GLOB)
174 			expandmeta(grabstackstr(p), dst->list);
175 		else
176 			appendarglist(dst->list, grabstackstr(p));
177 		dst->state = is_ws ? WORD_WS_DELIMITED : WORD_IDLE;
178 	} else if (!is_ws && dst->state == WORD_WS_DELIMITED)
179 		dst->state = WORD_IDLE;
180 	/* Reserve space while the stack string is empty. */
181 	appendarglist(dst->list, NULL);
182 	dst->list->count--;
183 	STARTSTACKSTR(p);
184 	return p;
185 }
186 #define NEXTWORD(c, flag, p, dstlist) p = nextword(c, flag, p, dstlist)
187 
188 static char *
stputs_split(const char * data,const char * syntax,int flag,char * p,struct worddest * dst)189 stputs_split(const char *data, const char *syntax, int flag, char *p,
190     struct worddest *dst)
191 {
192 	const char *ifs;
193 	char c;
194 
195 	ifs = ifsset() ? ifsval() : " \t\n";
196 	while (*data) {
197 		CHECKSTRSPACE(2, p);
198 		c = *data++;
199 		if (strchr(ifs, c) != NULL) {
200 			NEXTWORD(c, flag, p, dst);
201 			continue;
202 		}
203 		if (flag & EXP_GLOB && syntax[(int)c] == CCTL)
204 			USTPUTC(CTLESC, p);
205 		USTPUTC(c, p);
206 	}
207 	return (p);
208 }
209 #define STPUTS_SPLIT(data, syntax, flag, p, dst) p = stputs_split((data), syntax, flag, p, dst)
210 
211 /*
212  * Perform expansions on an argument, placing the resulting list of arguments
213  * in arglist.  Parameter expansion, command substitution and arithmetic
214  * expansion are always performed; additional expansions can be requested
215  * via flag (EXP_*).
216  * The result is left in the stack string.
217  * When arglist is NULL, perform here document expansion.
218  *
219  * When doing something that may cause this to be re-entered, make sure
220  * the stack string is empty via grabstackstr() and do not assume expdest
221  * remains valid.
222  */
223 void
expandarg(union node * arg,struct arglist * arglist,int flag)224 expandarg(union node *arg, struct arglist *arglist, int flag)
225 {
226 	struct worddest exparg;
227 	struct nodelist *argbackq;
228 
229 	if (fflag)
230 		flag &= ~EXP_GLOB;
231 	argbackq = arg->narg.backquote;
232 	exparg.list = arglist;
233 	exparg.state = WORD_IDLE;
234 	STARTSTACKSTR(expdest);
235 	argstr(arg->narg.text, &argbackq, flag, &exparg);
236 	if (arglist == NULL) {
237 		STACKSTRNUL(expdest);
238 		return;			/* here document expanded */
239 	}
240 	if ((flag & EXP_SPLIT) == 0 || expdest != stackblock() ||
241 	    exparg.state == WORD_QUOTEMARK) {
242 		STPUTC('\0', expdest);
243 		if (flag & EXP_SPLIT) {
244 			if (flag & EXP_GLOB)
245 				expandmeta(grabstackstr(expdest), exparg.list);
246 			else
247 				appendarglist(exparg.list, grabstackstr(expdest));
248 		}
249 	}
250 	if ((flag & EXP_SPLIT) == 0)
251 		appendarglist(arglist, grabstackstr(expdest));
252 }
253 
254 
255 
256 /*
257  * Perform parameter expansion, command substitution and arithmetic
258  * expansion, and tilde expansion if requested via EXP_TILDE/EXP_VARTILDE.
259  * Processing ends at a CTLENDVAR or CTLENDARI character as well as '\0'.
260  * This is used to expand word in ${var+word} etc.
261  * If EXP_GLOB or EXP_CASE are set, keep and/or generate CTLESC
262  * characters to allow for further processing.
263  *
264  * If EXP_SPLIT is set, dst receives any complete words produced.
265  */
266 static const char *
argstr(const char * p,struct nodelist ** restrict argbackq,int flag,struct worddest * dst)267 argstr(const char *p, struct nodelist **restrict argbackq, int flag,
268     struct worddest *dst)
269 {
270 	char c;
271 	int quotes = flag & (EXP_GLOB | EXP_CASE);	/* do CTLESC */
272 	int firsteq = 1;
273 	int split_lit;
274 	int lit_quoted;
275 
276 	split_lit = flag & EXP_SPLIT_LIT;
277 	lit_quoted = flag & EXP_LIT_QUOTED;
278 	flag &= ~(EXP_SPLIT_LIT | EXP_LIT_QUOTED);
279 	if (*p == '~' && (flag & (EXP_TILDE | EXP_VARTILDE)))
280 		p = exptilde(p, flag);
281 	for (;;) {
282 		CHECKSTRSPACE(2, expdest);
283 		switch (c = *p++) {
284 		case '\0':
285 			return (p - 1);
286 		case CTLENDVAR:
287 		case CTLENDARI:
288 			return (p);
289 		case CTLQUOTEMARK:
290 			lit_quoted = 1;
291 			/* "$@" syntax adherence hack */
292 			if (p[0] == CTLVAR && (p[1] & VSQUOTE) != 0 &&
293 			    p[2] == '@' && p[3] == '=')
294 				break;
295 			if ((flag & EXP_SPLIT) != 0 && expdest == stackblock())
296 				dst->state = WORD_QUOTEMARK;
297 			break;
298 		case CTLQUOTEEND:
299 			lit_quoted = 0;
300 			break;
301 		case CTLESC:
302 			c = *p++;
303 			if (split_lit && !lit_quoted &&
304 			    strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
305 				NEXTWORD(c, flag, expdest, dst);
306 				break;
307 			}
308 			if (quotes)
309 				USTPUTC(CTLESC, expdest);
310 			USTPUTC(c, expdest);
311 			break;
312 		case CTLVAR:
313 			p = evalvar(p, argbackq, flag, dst);
314 			break;
315 		case CTLBACKQ:
316 		case CTLBACKQ|CTLQUOTE:
317 			expbackq((*argbackq)->n, c & CTLQUOTE, flag, dst);
318 			*argbackq = (*argbackq)->next;
319 			break;
320 		case CTLARI:
321 			p = expari(p, argbackq, flag, dst);
322 			break;
323 		case ':':
324 		case '=':
325 			/*
326 			 * sort of a hack - expand tildes in variable
327 			 * assignments (after the first '=' and after ':'s).
328 			 */
329 			if (split_lit && !lit_quoted &&
330 			    strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
331 				NEXTWORD(c, flag, expdest, dst);
332 				break;
333 			}
334 			USTPUTC(c, expdest);
335 			if (flag & EXP_VARTILDE && *p == '~' &&
336 			    (c != '=' || firsteq)) {
337 				if (c == '=')
338 					firsteq = 0;
339 				p = exptilde(p, flag);
340 			}
341 			break;
342 		default:
343 			if (split_lit && !lit_quoted &&
344 			    strchr(ifsset() ? ifsval() : " \t\n", c) != NULL) {
345 				NEXTWORD(c, flag, expdest, dst);
346 				break;
347 			}
348 			USTPUTC(c, expdest);
349 		}
350 	}
351 }
352 
353 /*
354  * Perform tilde expansion, placing the result in the stack string and
355  * returning the next position in the input string to process.
356  */
357 static const char *
exptilde(const char * p,int flag)358 exptilde(const char *p, int flag)
359 {
360 	char c;
361 	const char *startp = p;
362 	const char *user;
363 	struct passwd *pw;
364 	char *home;
365 	int len;
366 
367 	for (;;) {
368 		c = *p;
369 		switch(c) {
370 		case CTLESC: /* This means CTL* are always considered quoted. */
371 		case CTLVAR:
372 		case CTLBACKQ:
373 		case CTLBACKQ | CTLQUOTE:
374 		case CTLARI:
375 		case CTLENDARI:
376 		case CTLQUOTEMARK:
377 			return (startp);
378 		case ':':
379 			if ((flag & EXP_VARTILDE) == 0)
380 				break;
381 			/* FALLTHROUGH */
382 		case '\0':
383 		case '/':
384 		case CTLENDVAR:
385 			len = p - startp - 1;
386 			STPUTBIN(startp + 1, len, expdest);
387 			STACKSTRNUL(expdest);
388 			user = expdest - len;
389 			if (*user == '\0') {
390 				home = lookupvar("HOME");
391 			} else {
392 				pw = getpwnam(user);
393 				home = pw != NULL ? pw->pw_dir : NULL;
394 			}
395 			STADJUST(-len, expdest);
396 			if (home == NULL || *home == '\0')
397 				return (startp);
398 			strtodest(home, flag, VSNORMAL, 1, NULL);
399 			return (p);
400 		}
401 		p++;
402 	}
403 }
404 
405 
406 /*
407  * Expand arithmetic expression.
408  */
409 static const char *
expari(const char * p,struct nodelist ** restrict argbackq,int flag,struct worddest * dst)410 expari(const char *p, struct nodelist **restrict argbackq, int flag,
411     struct worddest *dst)
412 {
413 	char *q, *start;
414 	arith_t result;
415 	int begoff;
416 	int quoted;
417 	int adj;
418 
419 	quoted = *p++ == '"';
420 	begoff = expdest - stackblock();
421 	p = argstr(p, argbackq, 0, NULL);
422 	STPUTC('\0', expdest);
423 	start = stackblock() + begoff;
424 
425 	q = grabstackstr(expdest);
426 	result = arith(start);
427 	ungrabstackstr(q, expdest);
428 
429 	start = stackblock() + begoff;
430 	adj = start - expdest;
431 	STADJUST(adj, expdest);
432 
433 	CHECKSTRSPACE((int)(DIGITS(result) + 1), expdest);
434 	fmtstr(expdest, DIGITS(result), ARITH_FORMAT_STR, result);
435 	adj = strlen(expdest);
436 	STADJUST(adj, expdest);
437 	/*
438 	 * If this is quoted, a '-' must not indicate a range in [...].
439 	 * If this is not quoted, splitting may occur.
440 	 */
441 	if (quoted ?
442 	    result < 0 && begoff > 1 && flag & (EXP_GLOB | EXP_CASE) :
443 	    flag & EXP_SPLIT)
444 		reprocess(expdest - adj - stackblock(), flag, VSNORMAL, quoted,
445 		    dst);
446 	return p;
447 }
448 
449 
450 /*
451  * Perform command substitution.
452  */
453 static void
expbackq(union node * cmd,int quoted,int flag,struct worddest * dst)454 expbackq(union node *cmd, int quoted, int flag, struct worddest *dst)
455 {
456 	struct backcmd in;
457 	int i;
458 	char buf[128];
459 	char *p;
460 	char *dest = expdest;
461 	char lastc;
462 	char const *syntax = quoted? DQSYNTAX : BASESYNTAX;
463 	int quotes = flag & (EXP_GLOB | EXP_CASE);
464 	size_t nnl;
465 	const char *ifs;
466 	int startloc;
467 
468 	INTOFF;
469 	p = grabstackstr(dest);
470 	evalbackcmd(cmd, &in);
471 	ungrabstackstr(p, dest);
472 
473 	p = in.buf;
474 	startloc = dest - stackblock();
475 	nnl = 0;
476 	if (!quoted && flag & EXP_SPLIT)
477 		ifs = ifsset() ? ifsval() : " \t\n";
478 	else
479 		ifs = "";
480 	/* Remove trailing newlines */
481 	for (;;) {
482 		if (--in.nleft < 0) {
483 			if (in.fd < 0)
484 				break;
485 			while ((i = read(in.fd, buf, sizeof buf)) < 0 && errno == EINTR)
486 				;
487 			TRACE(("expbackq: read returns %d\n", i));
488 			if (i <= 0)
489 				break;
490 			p = buf;
491 			in.nleft = i - 1;
492 		}
493 		lastc = *p++;
494 		if (lastc == '\0')
495 			continue;
496 		if (nnl > 0 && lastc != '\n') {
497 			NEXTWORD('\n', flag, dest, dst);
498 			nnl = 0;
499 		}
500 		if (strchr(ifs, lastc) != NULL) {
501 			if (lastc == '\n')
502 				nnl++;
503 			else
504 				NEXTWORD(lastc, flag, dest, dst);
505 		} else {
506 			CHECKSTRSPACE(2, dest);
507 			if (quotes && syntax[(int)lastc] == CCTL)
508 				USTPUTC(CTLESC, dest);
509 			USTPUTC(lastc, dest);
510 		}
511 	}
512 	while (dest > stackblock() + startloc && STTOPC(dest) == '\n')
513 		STUNPUTC(dest);
514 
515 	if (in.fd >= 0)
516 		close(in.fd);
517 	if (in.buf)
518 		ckfree(in.buf);
519 	if (in.jp) {
520 		p = grabstackstr(dest);
521 		exitstatus = waitforjob(in.jp, (int *)NULL);
522 		ungrabstackstr(p, dest);
523 	}
524 	TRACE(("expbackq: done\n"));
525 	expdest = dest;
526 	INTON;
527 }
528 
529 
530 
531 static void
recordleft(const char * str,const char * loc,char * startp)532 recordleft(const char *str, const char *loc, char *startp)
533 {
534 	int amount;
535 
536 	amount = ((str - 1) - (loc - startp)) - expdest;
537 	STADJUST(amount, expdest);
538 	while (loc != str - 1)
539 		*startp++ = *loc++;
540 }
541 
542 static const char *
subevalvar_trim(const char * p,struct nodelist ** restrict argbackq,int strloc,int subtype,int startloc)543 subevalvar_trim(const char *p, struct nodelist **restrict argbackq, int strloc,
544     int subtype, int startloc)
545 {
546 	char *startp;
547 	char *loc = NULL;
548 	char *str;
549 	int c = 0;
550 	int amount;
551 
552 	p = argstr(p, argbackq, EXP_CASE | EXP_TILDE, NULL);
553 	STACKSTRNUL(expdest);
554 	startp = stackblock() + startloc;
555 	str = stackblock() + strloc;
556 
557 	switch (subtype) {
558 	case VSTRIMLEFT:
559 		for (loc = startp; loc < str; loc++) {
560 			c = *loc;
561 			*loc = '\0';
562 			if (patmatch(str, startp)) {
563 				*loc = c;
564 				recordleft(str, loc, startp);
565 				return p;
566 			}
567 			*loc = c;
568 		}
569 		break;
570 
571 	case VSTRIMLEFTMAX:
572 		for (loc = str - 1; loc >= startp;) {
573 			c = *loc;
574 			*loc = '\0';
575 			if (patmatch(str, startp)) {
576 				*loc = c;
577 				recordleft(str, loc, startp);
578 				return p;
579 			}
580 			*loc = c;
581 			loc--;
582 		}
583 		break;
584 
585 	case VSTRIMRIGHT:
586 		for (loc = str - 1; loc >= startp;) {
587 			if (patmatch(str, loc)) {
588 				amount = loc - expdest;
589 				STADJUST(amount, expdest);
590 				return p;
591 			}
592 			loc--;
593 		}
594 		break;
595 
596 	case VSTRIMRIGHTMAX:
597 		for (loc = startp; loc < str - 1; loc++) {
598 			if (patmatch(str, loc)) {
599 				amount = loc - expdest;
600 				STADJUST(amount, expdest);
601 				return p;
602 			}
603 		}
604 		break;
605 
606 
607 	default:
608 		abort();
609 	}
610 	amount = (expdest - stackblock() - strloc) + 1;
611 	STADJUST(-amount, expdest);
612 	return p;
613 }
614 
615 
616 static const char *
subevalvar_misc(const char * p,struct nodelist ** restrict argbackq,const char * var,int subtype,int startloc,int varflags)617 subevalvar_misc(const char *p, struct nodelist **restrict argbackq,
618     const char *var, int subtype, int startloc, int varflags)
619 {
620 	const char *end;
621 	char *startp;
622 	int amount;
623 
624 	end = argstr(p, argbackq, EXP_TILDE, NULL);
625 	STACKSTRNUL(expdest);
626 	startp = stackblock() + startloc;
627 
628 	switch (subtype) {
629 	case VSASSIGN:
630 		setvar(var, startp, 0);
631 		amount = startp - expdest;
632 		STADJUST(amount, expdest);
633 		return end;
634 
635 	case VSQUESTION:
636 		if (*p != CTLENDVAR) {
637 			outfmt(out2, "%s\n", startp);
638 			error((char *)NULL);
639 		}
640 		error("%.*s: parameter %snot set", (int)(p - var - 1),
641 		      var, (varflags & VSNUL) ? "null or " : "");
642 
643 	default:
644 		abort();
645 	}
646 }
647 
648 
649 /*
650  * Expand a variable, and return a pointer to the next character in the
651  * input string.
652  */
653 
654 static const char *
evalvar(const char * p,struct nodelist ** restrict argbackq,int flag,struct worddest * dst)655 evalvar(const char *p, struct nodelist **restrict argbackq, int flag,
656     struct worddest *dst)
657 {
658 	int subtype;
659 	int varflags;
660 	const char *var;
661 	const char *val;
662 	int patloc;
663 	int c;
664 	int set;
665 	int special;
666 	int startloc;
667 	int varlen;
668 	int varlenb;
669 	char buf[21];
670 
671 	varflags = (unsigned char)*p++;
672 	subtype = varflags & VSTYPE;
673 	var = p;
674 	special = 0;
675 	if (! is_name(*p))
676 		special = 1;
677 	p = strchr(p, '=') + 1;
678 	if (varflags & VSLINENO) {
679 		set = 1;
680 		special = 1;
681 		val = NULL;
682 	} else if (special) {
683 		set = varisset(var, varflags & VSNUL);
684 		val = NULL;
685 	} else {
686 		val = bltinlookup(var, 1);
687 		if (val == NULL || ((varflags & VSNUL) && val[0] == '\0')) {
688 			val = NULL;
689 			set = 0;
690 		} else
691 			set = 1;
692 	}
693 	varlen = 0;
694 	startloc = expdest - stackblock();
695 	if (!set && uflag && *var != '@' && *var != '*') {
696 		switch (subtype) {
697 		case VSNORMAL:
698 		case VSTRIMLEFT:
699 		case VSTRIMLEFTMAX:
700 		case VSTRIMRIGHT:
701 		case VSTRIMRIGHTMAX:
702 		case VSLENGTH:
703 			error("%.*s: parameter not set", (int)(p - var - 1),
704 			    var);
705 		}
706 	}
707 	if (set && subtype != VSPLUS) {
708 		/* insert the value of the variable */
709 		if (special) {
710 			if (varflags & VSLINENO) {
711 				if (p - var > (ptrdiff_t)sizeof(buf))
712 					abort();
713 				memcpy(buf, var, p - var - 1);
714 				buf[p - var - 1] = '\0';
715 				strtodest(buf, flag, subtype,
716 				    varflags & VSQUOTE, dst);
717 			} else
718 				varvalue(var, varflags & VSQUOTE, subtype, flag,
719 				    dst);
720 			if (subtype == VSLENGTH) {
721 				varlenb = expdest - stackblock() - startloc;
722 				varlen = varlenb;
723 				if (localeisutf8) {
724 					val = stackblock() + startloc;
725 					for (;val != expdest; val++)
726 						if ((*val & 0xC0) == 0x80)
727 							varlen--;
728 				}
729 				STADJUST(-varlenb, expdest);
730 			}
731 		} else {
732 			if (subtype == VSLENGTH) {
733 				for (;*val; val++)
734 					if (!localeisutf8 ||
735 					    (*val & 0xC0) != 0x80)
736 						varlen++;
737 			}
738 			else
739 				strtodest(val, flag, subtype,
740 				    varflags & VSQUOTE, dst);
741 		}
742 	}
743 
744 	if (subtype == VSPLUS)
745 		set = ! set;
746 
747 	switch (subtype) {
748 	case VSLENGTH:
749 		cvtnum(varlen, buf);
750 		strtodest(buf, flag, VSNORMAL, varflags & VSQUOTE, dst);
751 		break;
752 
753 	case VSNORMAL:
754 		return p;
755 
756 	case VSPLUS:
757 	case VSMINUS:
758 		if (!set) {
759 			return argstr(p, argbackq,
760 			    flag | (flag & EXP_SPLIT ? EXP_SPLIT_LIT : 0) |
761 			    (varflags & VSQUOTE ? EXP_LIT_QUOTED : 0), dst);
762 		}
763 		break;
764 
765 	case VSTRIMLEFT:
766 	case VSTRIMLEFTMAX:
767 	case VSTRIMRIGHT:
768 	case VSTRIMRIGHTMAX:
769 		if (!set)
770 			break;
771 		/*
772 		 * Terminate the string and start recording the pattern
773 		 * right after it
774 		 */
775 		STPUTC('\0', expdest);
776 		patloc = expdest - stackblock();
777 		p = subevalvar_trim(p, argbackq, patloc, subtype, startloc);
778 		reprocess(startloc, flag, VSNORMAL, varflags & VSQUOTE, dst);
779 		if (flag & EXP_SPLIT && *var == '@' && varflags & VSQUOTE)
780 			dst->state = WORD_QUOTEMARK;
781 		return p;
782 
783 	case VSASSIGN:
784 	case VSQUESTION:
785 		if (!set) {
786 			p = subevalvar_misc(p, argbackq, var, subtype,
787 			    startloc, varflags);
788 			/* assert(subtype == VSASSIGN); */
789 			val = lookupvar(var);
790 			strtodest(val, flag, subtype, varflags & VSQUOTE, dst);
791 			return p;
792 		}
793 		break;
794 
795 	case VSERROR:
796 		c = p - var - 1;
797 		error("${%.*s%s}: Bad substitution", c, var,
798 		    (c > 0 && *p != CTLENDVAR) ? "..." : "");
799 
800 	default:
801 		abort();
802 	}
803 
804 	{	/* skip to end of alternative */
805 		int nesting = 1;
806 		for (;;) {
807 			if ((c = *p++) == CTLESC)
808 				p++;
809 			else if (c == CTLBACKQ || c == (CTLBACKQ|CTLQUOTE))
810 				*argbackq = (*argbackq)->next;
811 			else if (c == CTLVAR) {
812 				if ((*p++ & VSTYPE) != VSNORMAL)
813 					nesting++;
814 			} else if (c == CTLENDVAR) {
815 				if (--nesting == 0)
816 					break;
817 			}
818 		}
819 	}
820 	return p;
821 }
822 
823 
824 
825 /*
826  * Test whether a special or positional parameter is set.
827  */
828 
829 static int
varisset(const char * name,int nulok)830 varisset(const char *name, int nulok)
831 {
832 
833 	if (*name == '!')
834 		return backgndpidset();
835 	else if (*name == '@' || *name == '*') {
836 		if (*shellparam.p == NULL)
837 			return 0;
838 
839 		if (nulok) {
840 			char **av;
841 
842 			for (av = shellparam.p; *av; av++)
843 				if (**av != '\0')
844 					return 1;
845 			return 0;
846 		}
847 	} else if (is_digit(*name)) {
848 		char *ap;
849 		long num;
850 
851 		errno = 0;
852 		num = strtol(name, NULL, 10);
853 		if (errno != 0 || num > shellparam.nparam)
854 			return 0;
855 
856 		if (num == 0)
857 			ap = arg0;
858 		else
859 			ap = shellparam.p[num - 1];
860 
861 		if (nulok && (ap == NULL || *ap == '\0'))
862 			return 0;
863 	}
864 	return 1;
865 }
866 
867 static void
strtodest(const char * p,int flag,int subtype,int quoted,struct worddest * dst)868 strtodest(const char *p, int flag, int subtype, int quoted,
869     struct worddest *dst)
870 {
871 	if (subtype == VSLENGTH || subtype == VSTRIMLEFT ||
872 	    subtype == VSTRIMLEFTMAX || subtype == VSTRIMRIGHT ||
873 	    subtype == VSTRIMRIGHTMAX)
874 		STPUTS(p, expdest);
875 	else if (flag & EXP_SPLIT && !quoted && dst != NULL)
876 		STPUTS_SPLIT(p, BASESYNTAX, flag, expdest, dst);
877 	else if (flag & (EXP_GLOB | EXP_CASE))
878 		STPUTS_QUOTES(p, quoted ? DQSYNTAX : BASESYNTAX, expdest);
879 	else
880 		STPUTS(p, expdest);
881 }
882 
883 static void
reprocess(int startloc,int flag,int subtype,int quoted,struct worddest * dst)884 reprocess(int startloc, int flag, int subtype, int quoted,
885     struct worddest *dst)
886 {
887 	static char *buf = NULL;
888 	static size_t buflen = 0;
889 	char *startp;
890 	size_t len, zpos, zlen;
891 
892 	startp = stackblock() + startloc;
893 	len = expdest - startp;
894 	if (len >= SIZE_MAX / 2 || len > PTRDIFF_MAX)
895 		abort();
896 	INTOFF;
897 	if (len >= buflen) {
898 		ckfree(buf);
899 		buf = NULL;
900 	}
901 	if (buflen < 128)
902 		buflen = 128;
903 	while (len >= buflen)
904 		buflen <<= 1;
905 	if (buf == NULL)
906 		buf = ckmalloc(buflen);
907 	INTON;
908 	memcpy(buf, startp, len);
909 	buf[len] = '\0';
910 	STADJUST(-(ptrdiff_t)len, expdest);
911 	for (zpos = 0;;) {
912 		zlen = strlen(buf + zpos);
913 		strtodest(buf + zpos, flag, subtype, quoted, dst);
914 		zpos += zlen + 1;
915 		if (zpos == len + 1)
916 			break;
917 		if (flag & EXP_SPLIT && (quoted || (zlen > 0 && zpos < len)))
918 			NEXTWORD('\0', flag, expdest, dst);
919 	}
920 }
921 
922 /*
923  * Add the value of a special or positional parameter to the stack string.
924  */
925 
926 static void
varvalue(const char * name,int quoted,int subtype,int flag,struct worddest * dst)927 varvalue(const char *name, int quoted, int subtype, int flag,
928     struct worddest *dst)
929 {
930 	int num;
931 	char *p;
932 	int i;
933 	int splitlater;
934 	char sep[2];
935 	char **ap;
936 	char buf[(NSHORTOPTS > 10 ? NSHORTOPTS : 10) + 1];
937 
938 	if (subtype == VSLENGTH)
939 		flag &= ~EXP_FULL;
940 	splitlater = subtype == VSTRIMLEFT || subtype == VSTRIMLEFTMAX ||
941 		subtype == VSTRIMRIGHT || subtype == VSTRIMRIGHTMAX;
942 
943 	switch (*name) {
944 	case '$':
945 		num = rootpid;
946 		break;
947 	case '?':
948 		num = oexitstatus;
949 		break;
950 	case '#':
951 		num = shellparam.nparam;
952 		break;
953 	case '!':
954 		num = backgndpidval();
955 		break;
956 	case '-':
957 		p = buf;
958 		for (i = 0 ; i < NSHORTOPTS ; i++) {
959 			if (optval[i])
960 				*p++ = optletter[i];
961 		}
962 		*p = '\0';
963 		strtodest(buf, flag, subtype, quoted, dst);
964 		return;
965 	case '@':
966 		if (flag & EXP_SPLIT && quoted) {
967 			for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
968 				strtodest(p, flag, subtype, quoted, dst);
969 				if (*ap) {
970 					if (splitlater)
971 						STPUTC('\0', expdest);
972 					else
973 						NEXTWORD('\0', flag, expdest,
974 						    dst);
975 				}
976 			}
977 			if (shellparam.nparam > 0)
978 				dst->state = WORD_QUOTEMARK;
979 			return;
980 		}
981 		/* FALLTHROUGH */
982 	case '*':
983 		if (ifsset())
984 			sep[0] = ifsval()[0];
985 		else
986 			sep[0] = ' ';
987 		sep[1] = '\0';
988 		for (ap = shellparam.p ; (p = *ap++) != NULL ; ) {
989 			strtodest(p, flag, subtype, quoted, dst);
990 			if (!*ap)
991 				break;
992 			if (sep[0])
993 				strtodest(sep, flag, subtype, quoted, dst);
994 			else if (flag & EXP_SPLIT && !quoted && **ap != '\0') {
995 				if (splitlater)
996 					STPUTC('\0', expdest);
997 				else
998 					NEXTWORD('\0', flag, expdest, dst);
999 			}
1000 		}
1001 		return;
1002 	default:
1003 		if (is_digit(*name)) {
1004 			num = atoi(name);
1005 			if (num == 0)
1006 				p = arg0;
1007 			else if (num > 0 && num <= shellparam.nparam)
1008 				p = shellparam.p[num - 1];
1009 			else
1010 				return;
1011 			strtodest(p, flag, subtype, quoted, dst);
1012 		}
1013 		return;
1014 	}
1015 	cvtnum(num, buf);
1016 	strtodest(buf, flag, subtype, quoted, dst);
1017 }
1018 
1019 
1020 
1021 static char expdir[PATH_MAX];
1022 #define expdir_end (expdir + sizeof(expdir))
1023 
1024 /*
1025  * Perform pathname generation and remove control characters.
1026  * At this point, the only control characters should be CTLESC.
1027  * The results are stored in the list dstlist.
1028  */
1029 static void
expandmeta(char * pattern,struct arglist * dstlist)1030 expandmeta(char *pattern, struct arglist *dstlist)
1031 {
1032 	char *p;
1033 	int firstmatch;
1034 	char c;
1035 
1036 	firstmatch = dstlist->count;
1037 	p = pattern;
1038 	for (; (c = *p) != '\0'; p++) {
1039 		/* fast check for meta chars */
1040 		if (c == '*' || c == '?' || c == '[') {
1041 			INTOFF;
1042 			expmeta(expdir, pattern, dstlist);
1043 			INTON;
1044 			break;
1045 		}
1046 	}
1047 	if (dstlist->count == firstmatch) {
1048 		/*
1049 		 * no matches
1050 		 */
1051 		rmescapes(pattern);
1052 		appendarglist(dstlist, pattern);
1053 	} else {
1054 		qsort(&dstlist->args[firstmatch],
1055 		    dstlist->count - firstmatch,
1056 		    sizeof(dstlist->args[0]), expsortcmp);
1057 	}
1058 }
1059 
1060 
1061 /*
1062  * Do metacharacter (i.e. *, ?, [...]) expansion.
1063  */
1064 
1065 static void
expmeta(char * enddir,char * name,struct arglist * arglist)1066 expmeta(char *enddir, char *name, struct arglist *arglist)
1067 {
1068 	const char *p;
1069 	const char *q;
1070 	const char *start;
1071 	char *endname;
1072 	int metaflag;
1073 	struct stat statb;
1074 	DIR *dirp;
1075 	struct dirent *dp;
1076 	int atend;
1077 	int matchdot;
1078 	int esc;
1079 	int namlen;
1080 
1081 	metaflag = 0;
1082 	start = name;
1083 	for (p = name; esc = 0, *p; p += esc + 1) {
1084 		if (*p == '*' || *p == '?')
1085 			metaflag = 1;
1086 		else if (*p == '[') {
1087 			q = p + 1;
1088 			if (*q == '!' || *q == '^')
1089 				q++;
1090 			for (;;) {
1091 				if (*q == CTLESC)
1092 					q++;
1093 				if (*q == '/' || *q == '\0')
1094 					break;
1095 				if (*++q == ']') {
1096 					metaflag = 1;
1097 					break;
1098 				}
1099 			}
1100 		} else if (*p == '\0')
1101 			break;
1102 		else {
1103 			if (*p == CTLESC)
1104 				esc++;
1105 			if (p[esc] == '/') {
1106 				if (metaflag)
1107 					break;
1108 				start = p + esc + 1;
1109 			}
1110 		}
1111 	}
1112 	if (metaflag == 0) {	/* we've reached the end of the file name */
1113 		if (enddir != expdir)
1114 			metaflag++;
1115 		for (p = name ; ; p++) {
1116 			if (*p == CTLESC)
1117 				p++;
1118 			*enddir++ = *p;
1119 			if (*p == '\0')
1120 				break;
1121 			if (enddir == expdir_end)
1122 				return;
1123 		}
1124 		if (metaflag == 0 || lstat(expdir, &statb) >= 0)
1125 			appendarglist(arglist, stsavestr(expdir));
1126 		return;
1127 	}
1128 	endname = name + (p - name);
1129 	if (start != name) {
1130 		p = name;
1131 		while (p < start) {
1132 			if (*p == CTLESC)
1133 				p++;
1134 			*enddir++ = *p++;
1135 			if (enddir == expdir_end)
1136 				return;
1137 		}
1138 	}
1139 	if (enddir == expdir) {
1140 		p = ".";
1141 	} else if (enddir == expdir + 1 && *expdir == '/') {
1142 		p = "/";
1143 	} else {
1144 		p = expdir;
1145 		enddir[-1] = '\0';
1146 	}
1147 	if ((dirp = opendir(p)) == NULL)
1148 		return;
1149 	if (enddir != expdir)
1150 		enddir[-1] = '/';
1151 	if (*endname == 0) {
1152 		atend = 1;
1153 	} else {
1154 		atend = 0;
1155 		*endname = '\0';
1156 		endname += esc + 1;
1157 	}
1158 	matchdot = 0;
1159 	p = start;
1160 	if (*p == CTLESC)
1161 		p++;
1162 	if (*p == '.')
1163 		matchdot++;
1164 	while (! int_pending() && (dp = readdir(dirp)) != NULL) {
1165 		if (dp->d_name[0] == '.' && ! matchdot)
1166 			continue;
1167 		if (patmatch(start, dp->d_name)) {
1168 			namlen = dp->d_namlen;
1169 			if (enddir + namlen + 1 > expdir_end)
1170 				continue;
1171 			memcpy(enddir, dp->d_name, namlen + 1);
1172 			if (atend)
1173 				appendarglist(arglist, stsavestr(expdir));
1174 			else {
1175 				if (dp->d_type != DT_UNKNOWN &&
1176 				    dp->d_type != DT_DIR &&
1177 				    dp->d_type != DT_LNK)
1178 					continue;
1179 				if (enddir + namlen + 2 > expdir_end)
1180 					continue;
1181 				enddir[namlen] = '/';
1182 				enddir[namlen + 1] = '\0';
1183 				expmeta(enddir + namlen + 1, endname, arglist);
1184 			}
1185 		}
1186 	}
1187 	closedir(dirp);
1188 	if (! atend)
1189 		endname[-esc - 1] = esc ? CTLESC : '/';
1190 }
1191 
1192 
1193 static int
expsortcmp(const void * p1,const void * p2)1194 expsortcmp(const void *p1, const void *p2)
1195 {
1196 	const char *s1 = *(const char * const *)p1;
1197 	const char *s2 = *(const char * const *)p2;
1198 
1199 	return (strcoll(s1, s2));
1200 }
1201 
1202 
1203 
1204 static wchar_t
get_wc(const char ** p)1205 get_wc(const char **p)
1206 {
1207 	wchar_t c;
1208 	int chrlen;
1209 
1210 	chrlen = mbtowc(&c, *p, 4);
1211 	if (chrlen == 0)
1212 		return 0;
1213 	else if (chrlen == -1)
1214 		c = 0;
1215 	else
1216 		*p += chrlen;
1217 	return c;
1218 }
1219 
1220 
1221 /*
1222  * See if a character matches a character class, starting at the first colon
1223  * of "[:class:]".
1224  * If a valid character class is recognized, a pointer to the next character
1225  * after the final closing bracket is stored into *end, otherwise a null
1226  * pointer is stored into *end.
1227  */
1228 static int
match_charclass(const char * p,wchar_t chr,const char ** end)1229 match_charclass(const char *p, wchar_t chr, const char **end)
1230 {
1231 	char name[20];
1232 	const char *nameend;
1233 	wctype_t cclass;
1234 
1235 	*end = NULL;
1236 	p++;
1237 	nameend = strstr(p, ":]");
1238 	if (nameend == NULL || (size_t)(nameend - p) >= sizeof(name) ||
1239 	    nameend == p)
1240 		return 0;
1241 	memcpy(name, p, nameend - p);
1242 	name[nameend - p] = '\0';
1243 	*end = nameend + 2;
1244 	cclass = wctype(name);
1245 	/* An unknown class matches nothing but is valid nevertheless. */
1246 	if (cclass == 0)
1247 		return 0;
1248 	return iswctype(chr, cclass);
1249 }
1250 
1251 
1252 /*
1253  * Returns true if the pattern matches the string.
1254  */
1255 
1256 static int
patmatch(const char * pattern,const char * string)1257 patmatch(const char *pattern, const char *string)
1258 {
1259 	const char *p, *q, *end;
1260 	const char *bt_p, *bt_q;
1261 	char c;
1262 	wchar_t wc, wc2;
1263 
1264 	p = pattern;
1265 	q = string;
1266 	bt_p = NULL;
1267 	bt_q = NULL;
1268 	for (;;) {
1269 		switch (c = *p++) {
1270 		case '\0':
1271 			if (*q != '\0')
1272 				goto backtrack;
1273 			return 1;
1274 		case CTLESC:
1275 			if (*q++ != *p++)
1276 				goto backtrack;
1277 			break;
1278 		case '?':
1279 			if (*q == '\0')
1280 				return 0;
1281 			if (localeisutf8) {
1282 				wc = get_wc(&q);
1283 				/*
1284 				 * A '?' does not match invalid UTF-8 but a
1285 				 * '*' does, so backtrack.
1286 				 */
1287 				if (wc == 0)
1288 					goto backtrack;
1289 			} else
1290 				q++;
1291 			break;
1292 		case '*':
1293 			c = *p;
1294 			while (c == '*')
1295 				c = *++p;
1296 			/*
1297 			 * If the pattern ends here, we know the string
1298 			 * matches without needing to look at the rest of it.
1299 			 */
1300 			if (c == '\0')
1301 				return 1;
1302 			/*
1303 			 * First try the shortest match for the '*' that
1304 			 * could work. We can forget any earlier '*' since
1305 			 * there is no way having it match more characters
1306 			 * can help us, given that we are already here.
1307 			 */
1308 			bt_p = p;
1309 			bt_q = q;
1310 			break;
1311 		case '[': {
1312 			const char *savep, *saveq;
1313 			int invert, found;
1314 			wchar_t chr;
1315 
1316 			savep = p, saveq = q;
1317 			invert = 0;
1318 			if (*p == '!' || *p == '^') {
1319 				invert++;
1320 				p++;
1321 			}
1322 			found = 0;
1323 			if (*q == '\0')
1324 				return 0;
1325 			if (localeisutf8) {
1326 				chr = get_wc(&q);
1327 				if (chr == 0)
1328 					goto backtrack;
1329 			} else
1330 				chr = (unsigned char)*q++;
1331 			c = *p++;
1332 			do {
1333 				if (c == '\0') {
1334 					p = savep, q = saveq;
1335 					c = '[';
1336 					goto dft;
1337 				}
1338 				if (c == '[' && *p == ':') {
1339 					found |= match_charclass(p, chr, &end);
1340 					if (end != NULL) {
1341 						p = end;
1342 						continue;
1343 					}
1344 				}
1345 				if (c == CTLESC)
1346 					c = *p++;
1347 				if (localeisutf8 && c & 0x80) {
1348 					p--;
1349 					wc = get_wc(&p);
1350 					if (wc == 0) /* bad utf-8 */
1351 						return 0;
1352 				} else
1353 					wc = (unsigned char)c;
1354 				if (*p == '-' && p[1] != ']') {
1355 					p++;
1356 					if (*p == CTLESC)
1357 						p++;
1358 					if (localeisutf8) {
1359 						wc2 = get_wc(&p);
1360 						if (wc2 == 0) /* bad utf-8 */
1361 							return 0;
1362 					} else
1363 						wc2 = (unsigned char)*p++;
1364 					if (   collate_range_cmp(chr, wc) >= 0
1365 					    && collate_range_cmp(chr, wc2) <= 0
1366 					   )
1367 						found = 1;
1368 				} else {
1369 					if (chr == wc)
1370 						found = 1;
1371 				}
1372 			} while ((c = *p++) != ']');
1373 			if (found == invert)
1374 				goto backtrack;
1375 			break;
1376 		}
1377 dft:	        default:
1378 			if (*q == '\0')
1379 				return 0;
1380 			if (*q++ == c)
1381 				break;
1382 backtrack:
1383 			/*
1384 			 * If we have a mismatch (other than hitting the end
1385 			 * of the string), go back to the last '*' seen and
1386 			 * have it match one additional character.
1387 			 */
1388 			if (bt_p == NULL)
1389 				return 0;
1390 			if (*bt_q == '\0')
1391 				return 0;
1392 			bt_q++;
1393 			p = bt_p;
1394 			q = bt_q;
1395 			break;
1396 		}
1397 	}
1398 }
1399 
1400 
1401 
1402 /*
1403  * Remove any CTLESC and CTLQUOTEMARK characters from a string.
1404  */
1405 
1406 void
rmescapes(char * str)1407 rmescapes(char *str)
1408 {
1409 	char *p, *q;
1410 
1411 	p = str;
1412 	while (*p != CTLESC && *p != CTLQUOTEMARK && *p != CTLQUOTEEND) {
1413 		if (*p++ == '\0')
1414 			return;
1415 	}
1416 	q = p;
1417 	while (*p) {
1418 		if (*p == CTLQUOTEMARK || *p == CTLQUOTEEND) {
1419 			p++;
1420 			continue;
1421 		}
1422 		if (*p == CTLESC)
1423 			p++;
1424 		*q++ = *p++;
1425 	}
1426 	*q = '\0';
1427 }
1428 
1429 
1430 
1431 /*
1432  * See if a pattern matches in a case statement.
1433  */
1434 
1435 int
casematch(union node * pattern,const char * val)1436 casematch(union node *pattern, const char *val)
1437 {
1438 	struct stackmark smark;
1439 	struct nodelist *argbackq;
1440 	int result;
1441 	char *p;
1442 
1443 	setstackmark(&smark);
1444 	argbackq = pattern->narg.backquote;
1445 	STARTSTACKSTR(expdest);
1446 	argstr(pattern->narg.text, &argbackq, EXP_TILDE | EXP_CASE, NULL);
1447 	STPUTC('\0', expdest);
1448 	p = grabstackstr(expdest);
1449 	result = patmatch(p, val);
1450 	popstackmark(&smark);
1451 	return result;
1452 }
1453 
1454 /*
1455  * Our own itoa().
1456  */
1457 
1458 static void
cvtnum(int num,char * buf)1459 cvtnum(int num, char *buf)
1460 {
1461 	char temp[32];
1462 	int neg = num < 0;
1463 	char *p = temp + 31;
1464 
1465 	temp[31] = '\0';
1466 
1467 	do {
1468 		*--p = num % 10 + '0';
1469 	} while ((num /= 10) != 0);
1470 
1471 	if (neg)
1472 		*--p = '-';
1473 
1474 	memcpy(buf, p, temp + 32 - p);
1475 }
1476 
1477 /*
1478  * Do most of the work for wordexp(3).
1479  */
1480 
1481 int
wordexpcmd(int argc,char ** argv)1482 wordexpcmd(int argc, char **argv)
1483 {
1484 	size_t len;
1485 	int i;
1486 
1487 	out1fmt("%08x", argc - 1);
1488 	for (i = 1, len = 0; i < argc; i++)
1489 		len += strlen(argv[i]);
1490 	out1fmt("%08x", (int)len);
1491 	for (i = 1; i < argc; i++)
1492 		outbin(argv[i], strlen(argv[i]) + 1, out1);
1493         return (0);
1494 }
1495 
1496 /*
1497  * Do most of the work for wordexp(3), new version.
1498  */
1499 
1500 int
freebsd_wordexpcmd(int argc __unused,char ** argv __unused)1501 freebsd_wordexpcmd(int argc __unused, char **argv __unused)
1502 {
1503 	struct arglist arglist;
1504 	union node *args, *n;
1505 	size_t len;
1506 	int ch;
1507 	int protected = 0;
1508 	int fd = -1;
1509 	int i;
1510 
1511 	while ((ch = nextopt("f:p")) != '\0') {
1512 		switch (ch) {
1513 		case 'f':
1514 			fd = number(shoptarg);
1515 			break;
1516 		case 'p':
1517 			protected = 1;
1518 			break;
1519 		}
1520 	}
1521 	if (*argptr != NULL)
1522 		error("wrong number of arguments");
1523 	if (fd < 0)
1524 		error("missing fd");
1525 	INTOFF;
1526 	setinputfd(fd, 1);
1527 	INTON;
1528 	args = parsewordexp();
1529 	popfile(); /* will also close fd */
1530 	if (protected)
1531 		for (n = args; n != NULL; n = n->narg.next) {
1532 			if (n->narg.backquote != NULL) {
1533 				outcslow('C', out1);
1534 				error("command substitution disabled");
1535 			}
1536 		}
1537 	outcslow(' ', out1);
1538 	emptyarglist(&arglist);
1539 	for (n = args; n != NULL; n = n->narg.next)
1540 		expandarg(n, &arglist, EXP_FULL | EXP_TILDE);
1541 	for (i = 0, len = 0; i < arglist.count; i++)
1542 		len += strlen(arglist.args[i]);
1543 	out1fmt("%016x %016zx", arglist.count, len);
1544 	for (i = 0; i < arglist.count; i++)
1545 		outbin(arglist.args[i], strlen(arglist.args[i]) + 1, out1);
1546 	return (0);
1547 }
1548