xref: /openbsd-src/bin/csh/func.c (revision 91f110e064cd7c194e59e019b83bb7496c1c84d4)
1 /*    $OpenBSD: func.c,v 1.25 2009/10/27 23:59:21 deraadt Exp $       */
2 /*    $NetBSD: func.c,v 1.11 1996/02/09 02:28:29 christos Exp $       */
3 
4 /*-
5  * Copyright (c) 1980, 1991, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <signal.h>
36 #include <locale.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 #include <stdarg.h>
41 
42 #include "csh.h"
43 #include "extern.h"
44 #include "pathnames.h"
45 
46 extern char **environ;
47 
48 static int zlast = -1;
49 static void	islogin(void);
50 static void	reexecute(struct command *);
51 static void	preread(void);
52 static void	doagain(void);
53 static void	search(int, int, Char *);
54 static int	getword(Char *);
55 static int	keyword(Char *);
56 static void	toend(void);
57 static void	xecho(int, Char **);
58 static void	Unsetenv(Char *);
59 
60 struct biltins *
61 isbfunc(struct command *t)
62 {
63     Char *cp = t->t_dcom[0];
64     struct biltins *bp, *bp1, *bp2;
65     static struct biltins label = {"", dozip, 0, 0};
66     static struct biltins foregnd = {"%job", dofg1, 0, 0};
67     static struct biltins backgnd = {"%job &", dobg1, 0, 0};
68 
69     if (lastchr(cp) == ':') {
70 	label.bname = short2str(cp);
71 	return (&label);
72     }
73     if (*cp == '%') {
74 	if (t->t_dflg & F_AMPERSAND) {
75 	    t->t_dflg &= ~F_AMPERSAND;
76 	    backgnd.bname = short2str(cp);
77 	    return (&backgnd);
78 	}
79 	foregnd.bname = short2str(cp);
80 	return (&foregnd);
81     }
82     /*
83      * Binary search Bp1 is the beginning of the current search range. Bp2 is
84      * one past the end.
85      */
86     for (bp1 = bfunc, bp2 = bfunc + nbfunc; bp1 < bp2;) {
87 	int i;
88 
89 	bp = bp1 + ((bp2 - bp1) >> 1);
90 	if ((i = *cp - *bp->bname) == 0 &&
91 	    (i = Strcmp(cp, str2short(bp->bname))) == 0)
92 	    return bp;
93 	if (i < 0)
94 	    bp2 = bp;
95 	else
96 	    bp1 = bp + 1;
97     }
98     return (0);
99 }
100 
101 void
102 func(struct command *t, struct biltins *bp)
103 {
104     int     i;
105 
106     xechoit(t->t_dcom);
107     setname(bp->bname);
108     i = blklen(t->t_dcom) - 1;
109     if (i < bp->minargs)
110 	stderror(ERR_NAME | ERR_TOOFEW);
111     if (i > bp->maxargs)
112 	stderror(ERR_NAME | ERR_TOOMANY);
113     (*bp->bfunct) (t->t_dcom, t);
114 }
115 
116 void
117 /*ARGSUSED*/
118 doonintr(Char **v, struct command *t)
119 {
120     Char *cp;
121     Char *vv = v[1];
122     sigset_t sigset;
123 
124     if (parintr == SIG_IGN)
125 	return;
126     if (setintr && intty)
127 	stderror(ERR_NAME | ERR_TERMINAL);
128     cp = gointr;
129     gointr = 0;
130     xfree((ptr_t) cp);
131     if (vv == 0) {
132 	if (setintr) {
133 	    sigemptyset(&sigset);
134 	    sigaddset(&sigset, SIGINT);
135 	    sigprocmask(SIG_BLOCK, &sigset, NULL);
136 	} else
137 	    (void) signal(SIGINT, SIG_DFL);
138 	gointr = 0;
139     }
140     else if (eq((vv = strip(vv)), STRminus)) {
141 	(void) signal(SIGINT, SIG_IGN);
142 	gointr = Strsave(STRminus);
143     }
144     else {
145 	gointr = Strsave(vv);
146 	(void) signal(SIGINT, pintr);
147     }
148 }
149 
150 void
151 /*ARGSUSED*/
152 donohup(Char **v, struct command *t)
153 {
154     if (intty)
155 	stderror(ERR_NAME | ERR_TERMINAL);
156     if (setintr == 0) {
157 	(void) signal(SIGHUP, SIG_IGN);
158     }
159 }
160 
161 void
162 /*ARGSUSED*/
163 dozip(Char **v, struct command *t)
164 {
165     ;
166 }
167 
168 void
169 prvars(void)
170 {
171     plist(&shvhed);
172 }
173 
174 void
175 /*ARGSUSED*/
176 doalias(Char **v, struct command *t)
177 {
178     struct varent *vp;
179     Char *p;
180 
181     v++;
182     p = *v++;
183     if (p == 0)
184 	plist(&aliases);
185     else if (*v == 0) {
186 	vp = adrof1(strip(p), &aliases);
187 	if (vp) {
188 	    blkpr(cshout, vp->vec);
189 	    fputc('\n', cshout);
190 	}
191     }
192     else {
193 	if (eq(p, STRalias) || eq(p, STRunalias)) {
194 	    setname(vis_str(p));
195 	    stderror(ERR_NAME | ERR_DANGER);
196 	}
197 	set1(strip(p), saveblk(v), &aliases);
198     }
199 }
200 
201 void
202 /*ARGSUSED*/
203 unalias(Char **v, struct command *t)
204 {
205     unset1(v, &aliases);
206 }
207 
208 void
209 /*ARGSUSED*/
210 dologout(Char **v, struct command *t)
211 {
212     islogin();
213     goodbye();
214 }
215 
216 void
217 /*ARGSUSED*/
218 dologin(Char **v, struct command *t)
219 {
220     islogin();
221     rechist();
222     (void) signal(SIGTERM, parterm);
223     (void) execl(_PATH_LOGIN, "login", short2str(v[1]), (char *)NULL);
224     untty();
225     xexit(1);
226 }
227 
228 static void
229 islogin(void)
230 {
231     if (chkstop == 0 && setintr)
232 	panystop(0);
233     if (loginsh)
234 	return;
235     stderror(ERR_NOTLOGIN);
236 }
237 
238 void
239 doif(Char **v, struct command *kp)
240 {
241     int i;
242     Char **vv;
243 
244     v++;
245     i = expr(&v);
246     vv = v;
247     if (*vv == NULL)
248 	stderror(ERR_NAME | ERR_EMPTYIF);
249     if (eq(*vv, STRthen)) {
250 	if (*++vv)
251 	    stderror(ERR_NAME | ERR_IMPRTHEN);
252 	setname(vis_str(STRthen));
253 	/*
254 	 * If expression was zero, then scan to else, otherwise just fall into
255 	 * following code.
256 	 */
257 	if (!i)
258 	    search(T_IF, 0, NULL);
259 	return;
260     }
261     /*
262      * Simple command attached to this if. Left shift the node in this tree,
263      * munging it so we can reexecute it.
264      */
265     if (i) {
266 	lshift(kp->t_dcom, vv - kp->t_dcom);
267 	reexecute(kp);
268 	donefds();
269     }
270 }
271 
272 /*
273  * Reexecute a command, being careful not
274  * to redo i/o redirection, which is already set up.
275  */
276 static void
277 reexecute(struct command *kp)
278 {
279     kp->t_dflg &= F_SAVE;
280     kp->t_dflg |= F_REPEAT;
281     /*
282      * If tty is still ours to arbitrate, arbitrate it; otherwise dont even set
283      * pgrp's as the jobs would then have no way to get the tty (we can't give
284      * it to them, and our parent wouldn't know their pgrp, etc.
285      */
286     execute(kp, (tpgrp > 0 ? tpgrp : -1), NULL, NULL);
287 }
288 
289 void
290 /*ARGSUSED*/
291 doelse(Char **v, struct command *t)
292 {
293     search(T_ELSE, 0, NULL);
294 }
295 
296 void
297 /*ARGSUSED*/
298 dogoto(Char **v, struct command *t)
299 {
300     Char   *lp;
301 
302     gotolab(lp = globone(v[1], G_ERROR));
303     xfree((ptr_t) lp);
304 }
305 
306 void
307 gotolab(Char *lab)
308 {
309     struct whyle *wp;
310     /*
311      * While we still can, locate any unknown ends of existing loops. This
312      * obscure code is the WORST result of the fact that we don't really parse.
313      */
314     zlast = T_GOTO;
315     for (wp = whyles; wp; wp = wp->w_next)
316 	if (wp->w_end.type == F_SEEK && wp->w_end.f_seek == 0) {
317 	    search(T_BREAK, 0, NULL);
318 	    btell(&wp->w_end);
319 	}
320 	else
321 	    bseek(&wp->w_end);
322     search(T_GOTO, 0, lab);
323     /*
324      * Eliminate loops which were exited.
325      */
326     wfree();
327 }
328 
329 void
330 /*ARGSUSED*/
331 doswitch(Char **v, struct command *t)
332 {
333     Char *cp, *lp;
334 
335     v++;
336     if (!*v || *(*v++) != '(')
337 	stderror(ERR_SYNTAX);
338     cp = **v == ')' ? STRNULL : *v++;
339     if (*(*v++) != ')')
340 	v--;
341     if (*v)
342 	stderror(ERR_SYNTAX);
343     search(T_SWITCH, 0, lp = globone(cp, G_ERROR));
344     xfree((ptr_t) lp);
345 }
346 
347 void
348 /*ARGSUSED*/
349 dobreak(Char **v, struct command *t)
350 {
351     if (whyles)
352 	toend();
353     else
354 	stderror(ERR_NAME | ERR_NOTWHILE);
355 }
356 
357 void
358 /*ARGSUSED*/
359 doexit(Char **v, struct command *t)
360 {
361     if (chkstop == 0 && (intty || intact) && evalvec == 0)
362 	panystop(0);
363     /*
364      * Don't DEMAND parentheses here either.
365      */
366     v++;
367     if (*v) {
368 	set(STRstatus, putn(expr(&v)));
369 	if (*v)
370 	    stderror(ERR_NAME | ERR_EXPRESSION);
371     }
372     btoeof();
373     if (intty)
374 	(void) close(SHIN);
375 }
376 
377 void
378 /*ARGSUSED*/
379 doforeach(Char **v, struct command *t)
380 {
381     Char *cp, *sp;
382     struct whyle *nwp;
383 
384     v++;
385     sp = cp = strip(*v);
386     if (!letter(*sp))
387 	stderror(ERR_NAME | ERR_VARBEGIN);
388     while (*cp && alnum(*cp))
389 	cp++;
390     if (*cp)
391 	stderror(ERR_NAME | ERR_VARALNUM);
392     if ((cp - sp) > MAXVARLEN)
393 	stderror(ERR_NAME | ERR_VARTOOLONG);
394     cp = *v++;
395     if (v[0][0] != '(' || v[blklen(v) - 1][0] != ')')
396 	stderror(ERR_NAME | ERR_NOPAREN);
397     v++;
398     gflag = 0, tglob(v);
399     v = globall(v);
400     if (v == 0)
401 	stderror(ERR_NAME | ERR_NOMATCH);
402     nwp = (struct whyle *) xcalloc(1, sizeof *nwp);
403     nwp->w_fe = nwp->w_fe0 = v;
404     gargv = 0;
405     btell(&nwp->w_start);
406     nwp->w_fename = Strsave(cp);
407     nwp->w_next = whyles;
408     nwp->w_end.type = F_SEEK;
409     whyles = nwp;
410     /*
411      * Pre-read the loop so as to be more comprehensible to a terminal user.
412      */
413     zlast = T_FOREACH;
414     if (intty)
415 	preread();
416     doagain();
417 }
418 
419 void
420 /*ARGSUSED*/
421 dowhile(Char **v, struct command *t)
422 {
423     int status;
424     bool again = whyles != 0 && SEEKEQ(&whyles->w_start, &lineloc) &&
425     whyles->w_fename == 0;
426 
427     v++;
428     /*
429      * Implement prereading here also, taking care not to evaluate the
430      * expression before the loop has been read up from a terminal.
431      */
432     if (intty && !again)
433 	status = !exp0(&v, 1);
434     else
435 	status = !expr(&v);
436     if (*v)
437 	stderror(ERR_NAME | ERR_EXPRESSION);
438     if (!again) {
439 	struct whyle *nwp =
440 	(struct whyle *) xcalloc(1, sizeof(*nwp));
441 
442 	nwp->w_start = lineloc;
443 	nwp->w_end.type = F_SEEK;
444 	nwp->w_end.f_seek = 0;
445 	nwp->w_next = whyles;
446 	whyles = nwp;
447 	zlast = T_WHILE;
448 	if (intty) {
449 	    /*
450 	     * The tty preread
451 	     */
452 	    preread();
453 	    doagain();
454 	    return;
455 	}
456     }
457     if (status)
458 	/* We ain't gonna loop no more, no more! */
459 	toend();
460 }
461 
462 static void
463 preread(void)
464 {
465     sigset_t sigset;
466 
467     whyles->w_end.type = I_SEEK;
468     if (setintr) {
469 	sigemptyset(&sigset);
470 	sigaddset(&sigset, SIGINT);
471 	sigprocmask(SIG_UNBLOCK, &sigset, NULL);
472     }
473 
474     search(T_BREAK, 0, NULL);		/* read the expression in */
475     if (setintr)
476 	sigprocmask(SIG_BLOCK, &sigset, NULL);
477     btell(&whyles->w_end);
478 }
479 
480 void
481 /*ARGSUSED*/
482 doend(Char **v, struct command *t)
483 {
484     if (!whyles)
485 	stderror(ERR_NAME | ERR_NOTWHILE);
486     btell(&whyles->w_end);
487     doagain();
488 }
489 
490 void
491 /*ARGSUSED*/
492 docontin(Char **v, struct command *t)
493 {
494     if (!whyles)
495 	stderror(ERR_NAME | ERR_NOTWHILE);
496     doagain();
497 }
498 
499 static void
500 doagain(void)
501 {
502     /* Repeating a while is simple */
503     if (whyles->w_fename == 0) {
504 	bseek(&whyles->w_start);
505 	return;
506     }
507     /*
508      * The foreach variable list actually has a spurious word ")" at the end of
509      * the w_fe list.  Thus we are at the of the list if one word beyond this
510      * is 0.
511      */
512     if (!whyles->w_fe[1]) {
513 	dobreak(NULL, NULL);
514 	return;
515     }
516     set(whyles->w_fename, Strsave(*whyles->w_fe++));
517     bseek(&whyles->w_start);
518 }
519 
520 void
521 dorepeat(Char **v, struct command *kp)
522 {
523     int i;
524     sigset_t sigset;
525 
526     i = getn(v[1]);
527     if (setintr) {
528 	sigemptyset(&sigset);
529 	sigaddset(&sigset, SIGINT);
530 	sigprocmask(SIG_BLOCK, &sigset, NULL);
531     }
532     lshift(v, 2);
533     while (i > 0) {
534 	if (setintr)
535 	    sigprocmask(SIG_UNBLOCK, &sigset, NULL);
536 	reexecute(kp);
537 	--i;
538     }
539     donefds();
540     if (setintr)
541 	sigprocmask(SIG_UNBLOCK, &sigset, NULL);
542 }
543 
544 void
545 /*ARGSUSED*/
546 doswbrk(Char **v, struct command *t)
547 {
548     search(T_BRKSW, 0, NULL);
549 }
550 
551 int
552 srchx(Char *cp)
553 {
554     struct srch *sp, *sp1, *sp2;
555     int i;
556 
557     /*
558      * Binary search Sp1 is the beginning of the current search range. Sp2 is
559      * one past the end.
560      */
561     for (sp1 = srchn, sp2 = srchn + nsrchn; sp1 < sp2;) {
562 	sp = sp1 + ((sp2 - sp1) >> 1);
563 	if ((i = *cp - *sp->s_name) == 0 &&
564 	    (i = Strcmp(cp, str2short(sp->s_name))) == 0)
565 	    return sp->s_value;
566 	if (i < 0)
567 	    sp2 = sp;
568 	else
569 	    sp1 = sp + 1;
570     }
571     return (-1);
572 }
573 
574 static Char Stype;
575 static Char *Sgoal;
576 
577 /*VARARGS2*/
578 static void
579 search(int type, int level, Char *goal)
580 {
581     Char    wordbuf[BUFSIZ];
582     Char *aword = wordbuf;
583     Char *cp;
584 
585     Stype = type;
586     Sgoal = goal;
587     if (type == T_GOTO) {
588 	struct Ain a;
589 	a.type = F_SEEK;
590 	a.f_seek = 0;
591 	bseek(&a);
592     }
593     do {
594 	if (intty && fseekp == feobp && aret == F_SEEK)
595 	    (void) fprintf(cshout, "? "), (void) fflush(cshout);
596 	aword[0] = 0;
597 	(void) getword(aword);
598 	switch (srchx(aword)) {
599 
600 	case T_ELSE:
601 	    if (level == 0 && type == T_IF)
602 		return;
603 	    break;
604 
605 	case T_IF:
606 	    while (getword(aword))
607 		continue;
608 	    if ((type == T_IF || type == T_ELSE) &&
609 		eq(aword, STRthen))
610 		level++;
611 	    break;
612 
613 	case T_ENDIF:
614 	    if (type == T_IF || type == T_ELSE)
615 		level--;
616 	    break;
617 
618 	case T_FOREACH:
619 	case T_WHILE:
620 	    if (type == T_BREAK)
621 		level++;
622 	    break;
623 
624 	case T_END:
625 	    if (type == T_BREAK)
626 		level--;
627 	    break;
628 
629 	case T_SWITCH:
630 	    if (type == T_SWITCH || type == T_BRKSW)
631 		level++;
632 	    break;
633 
634 	case T_ENDSW:
635 	    if (type == T_SWITCH || type == T_BRKSW)
636 		level--;
637 	    break;
638 
639 	case T_LABEL:
640 	    if (type == T_GOTO && getword(aword) && eq(aword, goal))
641 		level = -1;
642 	    break;
643 
644 	default:
645 	    if (type != T_GOTO && (type != T_SWITCH || level != 0))
646 		break;
647 	    if (lastchr(aword) != ':')
648 		break;
649 	    aword[Strlen(aword) - 1] = 0;
650 	    if ((type == T_GOTO && eq(aword, goal)) ||
651 		(type == T_SWITCH && eq(aword, STRdefault)))
652 		level = -1;
653 	    break;
654 
655 	case T_CASE:
656 	    if (type != T_SWITCH || level != 0)
657 		break;
658 	    (void) getword(aword);
659 	    if (lastchr(aword) == ':')
660 		aword[Strlen(aword) - 1] = 0;
661 	    cp = strip(Dfix1(aword));
662 	    if (Gmatch(goal, cp))
663 		level = -1;
664 	    xfree((ptr_t) cp);
665 	    break;
666 
667 	case T_DEFAULT:
668 	    if (type == T_SWITCH && level == 0)
669 		level = -1;
670 	    break;
671 	}
672 	(void) getword(NULL);
673     } while (level >= 0);
674 }
675 
676 static int
677 getword(Char *wp)
678 {
679     int found = 0;
680     int c, d;
681     int     kwd = 0;
682     Char   *owp = wp;
683 
684     c = readc(1);
685     d = 0;
686     do {
687 	while (c == ' ' || c == '\t')
688 	    c = readc(1);
689 	if (c == '#')
690 	    do
691 		c = readc(1);
692 	    while (c >= 0 && c != '\n');
693 	if (c < 0)
694 	    goto past;
695 	if (c == '\n') {
696 	    if (wp)
697 		break;
698 	    return (0);
699 	}
700 	unreadc(c);
701 	found = 1;
702 	do {
703 	    c = readc(1);
704 	    if (c == '\\' && (c = readc(1)) == '\n')
705 		c = ' ';
706 	    if (c == '\'' || c == '"') {
707 		if (d == 0)
708 		    d = c;
709 		else if (d == c)
710 		    d = 0;
711 	    }
712 	    if (c < 0)
713 		goto past;
714 	    if (wp) {
715 		*wp++ = c;
716 		*wp = 0;	/* end the string b4 test */
717 	    }
718 	} while ((d || (!(kwd = keyword(owp)) && c != ' '
719 		  && c != '\t')) && c != '\n');
720     } while (wp == 0);
721 
722     /*
723      * if we have read a keyword ( "if", "switch" or "while" ) then we do not
724      * need to unreadc the look-ahead char
725      */
726     if (!kwd) {
727 	unreadc(c);
728 	if (found)
729 	    *--wp = 0;
730     }
731 
732     return (found);
733 
734 past:
735     switch (Stype) {
736 
737     case T_IF:
738 	stderror(ERR_NAME | ERR_NOTFOUND, "then/endif");
739 
740     case T_ELSE:
741 	stderror(ERR_NAME | ERR_NOTFOUND, "endif");
742 
743     case T_BRKSW:
744     case T_SWITCH:
745 	stderror(ERR_NAME | ERR_NOTFOUND, "endsw");
746 
747     case T_BREAK:
748 	stderror(ERR_NAME | ERR_NOTFOUND, "end");
749 
750     case T_GOTO:
751 	setname(vis_str(Sgoal));
752 	stderror(ERR_NAME | ERR_NOTFOUND, "label");
753     }
754     /* NOTREACHED */
755     return (0);
756 }
757 
758 /*
759  * keyword(wp) determines if wp is one of the built-n functions if,
760  * switch or while. It seems that when an if statement looks like
761  * "if(" then getword above sucks in the '(' and so the search routine
762  * never finds what it is scanning for. Rather than rewrite doword, I hack
763  * in a test to see if the string forms a keyword. Then doword stops
764  * and returns the word "if" -strike
765  */
766 
767 static int
768 keyword(Char *wp)
769 {
770     static Char STRif[] = {'i', 'f', '\0'};
771     static Char STRwhile[] = {'w', 'h', 'i', 'l', 'e', '\0'};
772     static Char STRswitch[] = {'s', 'w', 'i', 't', 'c', 'h', '\0'};
773 
774     if (!wp)
775 	return (0);
776 
777     if ((Strcmp(wp, STRif) == 0) || (Strcmp(wp, STRwhile) == 0)
778 	|| (Strcmp(wp, STRswitch) == 0))
779 	return (1);
780 
781     return (0);
782 }
783 
784 static void
785 toend(void)
786 {
787     if (whyles->w_end.type == F_SEEK && whyles->w_end.f_seek == 0) {
788 	search(T_BREAK, 0, NULL);
789 	btell(&whyles->w_end);
790 	whyles->w_end.f_seek--;
791     }
792     else
793 	bseek(&whyles->w_end);
794     wfree();
795 }
796 
797 void
798 wfree(void)
799 {
800     struct Ain    o;
801     struct whyle *nwp;
802 
803     btell(&o);
804 
805     for (; whyles; whyles = nwp) {
806 	struct whyle *wp = whyles;
807 	nwp = wp->w_next;
808 
809 	/*
810 	 * We free loops that have different seek types.
811 	 */
812 	if (wp->w_end.type != I_SEEK && wp->w_start.type == wp->w_end.type &&
813 	    wp->w_start.type == o.type) {
814 	    if (wp->w_end.type == F_SEEK) {
815 		if (o.f_seek >= wp->w_start.f_seek &&
816 		    (wp->w_end.f_seek == 0 || o.f_seek < wp->w_end.f_seek))
817 		    break;
818 	    }
819 	    else {
820 		if (o.a_seek >= wp->w_start.a_seek &&
821 		    (wp->w_end.a_seek == 0 || o.a_seek < wp->w_end.a_seek))
822 		    break;
823 	    }
824 	}
825 
826 	if (wp->w_fe0)
827 	    blkfree(wp->w_fe0);
828 	if (wp->w_fename)
829 	    xfree((ptr_t) wp->w_fename);
830 	xfree((ptr_t) wp);
831     }
832 }
833 
834 void
835 /*ARGSUSED*/
836 doecho(Char **v, struct command *t)
837 {
838     xecho(' ', v);
839 }
840 
841 void
842 /*ARGSUSED*/
843 doglob(Char **v, struct command *t)
844 {
845     xecho(0, v);
846     (void) fflush(cshout);
847 }
848 
849 static void
850 xecho(int sep, Char **v)
851 {
852     Char *cp;
853     int     nonl = 0;
854     sigset_t sigset;
855 
856     if (setintr) {
857 	sigemptyset(&sigset);
858 	sigaddset(&sigset, SIGINT);
859 	sigprocmask(SIG_UNBLOCK, &sigset, NULL);
860     }
861     v++;
862     if (*v == 0)
863 	return;
864     gflag = 0, tglob(v);
865     if (gflag) {
866 	v = globall(v);
867 	if (v == 0)
868 	    stderror(ERR_NAME | ERR_NOMATCH);
869     }
870     else {
871 	v = gargv = saveblk(v);
872 	trim(v);
873     }
874     if (sep == ' ' && *v && eq(*v, STRmn))
875 	nonl++, v++;
876     while ((cp = *v++) != NULL) {
877 	int c;
878 
879 	while ((c = *cp++) != '\0')
880 	    (void) vis_fputc(c | QUOTE, cshout);
881 
882 	if (*v)
883 	    (void) vis_fputc(sep | QUOTE, cshout);
884     }
885     if (sep && nonl == 0)
886 	(void) fputc('\n', cshout);
887     else
888 	(void) fflush(cshout);
889     if (setintr)
890 	sigprocmask(SIG_BLOCK, &sigset, NULL);
891     if (gargv)
892 	blkfree(gargv), gargv = 0;
893 }
894 
895 void
896 /*ARGSUSED*/
897 dosetenv(Char **v, struct command *t)
898 {
899     Char   *vp, *lp;
900     sigset_t sigset;
901 
902     v++;
903     if ((vp = *v++) == 0) {
904 	Char **ep;
905 
906 	if (setintr) {
907 	    sigemptyset(&sigset);
908 	    sigaddset(&sigset, SIGINT);
909 	    sigprocmask(SIG_UNBLOCK, &sigset, NULL);
910 	}
911 	for (ep = STR_environ; *ep; ep++)
912 	    (void) fprintf(cshout, "%s\n", vis_str(*ep));
913 	return;
914     }
915     if ((lp = *v++) == 0)
916 	lp = STRNULL;
917     Setenv(vp, lp = globone(lp, G_APPEND));
918     if (eq(vp, STRPATH)) {
919 	importpath(lp);
920 	dohash(NULL, NULL);
921     }
922     else if (eq(vp, STRLANG) || eq(vp, STRLC_CTYPE)) {
923 #ifdef NLS
924 	int     k;
925 
926 	(void) setlocale(LC_ALL, "");
927 	for (k = 0200; k <= 0377 && !Isprint(k); k++)
928 		continue;
929 	AsciiOnly = k > 0377;
930 #else
931 	AsciiOnly = 0;
932 #endif				/* NLS */
933     }
934     xfree((ptr_t) lp);
935 }
936 
937 void
938 /*ARGSUSED*/
939 dounsetenv(Char **v, struct command *t)
940 {
941     Char  **ep, *p, *n;
942     int     i, maxi;
943     static Char *name = NULL;
944 
945     if (name)
946 	xfree((ptr_t) name);
947     /*
948      * Find the longest environment variable
949      */
950     for (maxi = 0, ep = STR_environ; *ep; ep++) {
951 	for (i = 0, p = *ep; *p && *p != '='; p++, i++)
952 	    continue;
953 	if (i > maxi)
954 	    maxi = i;
955     }
956 
957     name = (Char *) xmalloc((size_t) (maxi + 1) * sizeof(Char));
958 
959     while (++v && *v)
960 	for (maxi = 1; maxi;)
961 	    for (maxi = 0, ep = STR_environ; *ep; ep++) {
962 		for (n = name, p = *ep; *p && *p != '='; *n++ = *p++)
963 		    continue;
964 		*n = '\0';
965 		if (!Gmatch(name, *v))
966 		    continue;
967 		maxi = 1;
968 		if (eq(name, STRLANG) || eq(name, STRLC_CTYPE)) {
969 #ifdef NLS
970 		    int     k;
971 
972 		    (void) setlocale(LC_ALL, "");
973 		    for (k = 0200; k <= 0377 && !Isprint(k); k++)
974 			continue;
975 		    AsciiOnly = k > 0377;
976 #else
977 		    AsciiOnly = getenv("LANG") == NULL &&
978 			getenv("LC_CTYPE") == NULL;
979 #endif				/* NLS */
980 		}
981 		/*
982 		 * Delete name, and start again cause the environment changes
983 		 */
984 		Unsetenv(name);
985 		break;
986 	    }
987     xfree((ptr_t) name);
988     name = NULL;
989 }
990 
991 void
992 Setenv(Char *name, Char *val)
993 {
994     Char **ep = STR_environ;
995     Char *cp, *dp;
996     Char   *blk[2];
997     Char  **oep = ep;
998 
999     for (; *ep; ep++) {
1000 	for (cp = name, dp = *ep; *cp && *cp == *dp; cp++, dp++)
1001 	    continue;
1002 	if (*cp != 0 || *dp != '=')
1003 	    continue;
1004 	cp = Strspl(STRequal, val);
1005 	xfree((ptr_t) * ep);
1006 	*ep = strip(Strspl(name, cp));
1007 	xfree((ptr_t) cp);
1008 	blkfree((Char **) environ);
1009 	environ = short2blk(STR_environ);
1010 	return;
1011     }
1012     cp = Strspl(name, STRequal);
1013     blk[0] = strip(Strspl(cp, val));
1014     xfree((ptr_t) cp);
1015     blk[1] = 0;
1016     STR_environ = blkspl(STR_environ, blk);
1017     blkfree((Char **) environ);
1018     environ = short2blk(STR_environ);
1019     xfree((ptr_t) oep);
1020 }
1021 
1022 static void
1023 Unsetenv(Char *name)
1024 {
1025     Char **ep = STR_environ;
1026     Char *cp, *dp;
1027     Char  **oep = ep;
1028 
1029     for (; *ep; ep++) {
1030 	for (cp = name, dp = *ep; *cp && *cp == *dp; cp++, dp++)
1031 	    continue;
1032 	if (*cp != 0 || *dp != '=')
1033 	    continue;
1034 	cp = *ep;
1035 	*ep = 0;
1036 	STR_environ = blkspl(STR_environ, ep + 1);
1037 	environ = short2blk(STR_environ);
1038 	*ep = cp;
1039 	xfree((ptr_t) cp);
1040 	xfree((ptr_t) oep);
1041 	return;
1042     }
1043 }
1044 
1045 void
1046 /*ARGSUSED*/
1047 doumask(Char **v, struct command *t)
1048 {
1049     Char *cp = v[1];
1050     int i;
1051 
1052     if (cp == 0) {
1053 	i = umask(0);
1054 	(void) umask(i);
1055 	(void) fprintf(cshout, "%o\n", i);
1056 	return;
1057     }
1058     i = 0;
1059     while (Isdigit(*cp) && *cp != '8' && *cp != '9')
1060 	i = i * 8 + *cp++ - '0';
1061     if (*cp || i < 0 || i > 0777)
1062 	stderror(ERR_NAME | ERR_MASK);
1063     (void) umask(i);
1064 }
1065 
1066 typedef quad_t RLIM_TYPE;
1067 
1068 static struct limits {
1069     int     limconst;
1070     char   *limname;
1071     int     limdiv;
1072     char   *limscale;
1073 }       limits[] = {
1074     { RLIMIT_CPU,	"cputime",	1,	"seconds" },
1075     { RLIMIT_FSIZE,	"filesize",	1024,	"kbytes" },
1076     { RLIMIT_DATA,	"datasize",	1024,	"kbytes" },
1077     { RLIMIT_STACK,	"stacksize",	1024,	"kbytes" },
1078     { RLIMIT_CORE,	"coredumpsize", 1024,	"kbytes" },
1079     { RLIMIT_RSS,	"memoryuse",	1024,	"kbytes" },
1080 #ifdef RLIMIT_VMEM
1081     { RLIMIT_VMEM,	"vmemoryuse",	1024,	"kbytes" },
1082 #endif
1083     { RLIMIT_MEMLOCK,	"memorylocked",	1024,	"kbytes" },
1084     { RLIMIT_NPROC,	"maxproc",	1,	"" },
1085     { RLIMIT_NOFILE,	"openfiles",	1,	"" },
1086     { -1,		NULL,		0,	NULL }
1087 };
1088 
1089 static struct limits *findlim(Char *);
1090 static RLIM_TYPE getval(struct limits *, Char **);
1091 static void limtail(Char *, char *);
1092 static void plim(struct limits *, Char);
1093 static int setlim(struct limits *, Char, RLIM_TYPE);
1094 
1095 static struct limits *
1096 findlim(Char *cp)
1097 {
1098     struct limits *lp, *res;
1099 
1100     res = NULL;
1101     for (lp = limits; lp->limconst >= 0; lp++)
1102 	if (prefix(cp, str2short(lp->limname))) {
1103 	    if (res)
1104 		stderror(ERR_NAME | ERR_AMBIG);
1105 	    res = lp;
1106 	}
1107     if (res)
1108 	return (res);
1109     stderror(ERR_NAME | ERR_LIMIT);
1110     /* NOTREACHED */
1111     return (0);
1112 }
1113 
1114 void
1115 /*ARGSUSED*/
1116 dolimit(Char **v, struct command *t)
1117 {
1118     struct limits *lp;
1119     RLIM_TYPE limit;
1120     char    hard = 0;
1121 
1122     v++;
1123     if (*v && eq(*v, STRmh)) {
1124 	hard = 1;
1125 	v++;
1126     }
1127     if (*v == 0) {
1128 	for (lp = limits; lp->limconst >= 0; lp++)
1129 	    plim(lp, hard);
1130 	return;
1131     }
1132     lp = findlim(v[0]);
1133     if (v[1] == 0) {
1134 	plim(lp, hard);
1135 	return;
1136     }
1137     limit = getval(lp, v + 1);
1138     if (setlim(lp, hard, limit) < 0)
1139 	stderror(ERR_SILENT);
1140 }
1141 
1142 static  RLIM_TYPE
1143 getval(struct limits *lp, Char **v)
1144 {
1145     float f;
1146     Char   *cp = *v++;
1147 
1148     f = atof(short2str(cp));
1149 
1150     while (Isdigit(*cp) || *cp == '.' || *cp == 'e' || *cp == 'E')
1151 	cp++;
1152     if (*cp == 0) {
1153 	if (*v == 0)
1154 	    return ((RLIM_TYPE) ((f + 0.5) * lp->limdiv));
1155 	cp = *v;
1156     }
1157     switch (*cp) {
1158     case ':':
1159 	if (lp->limconst != RLIMIT_CPU)
1160 	    goto badscal;
1161 	return ((RLIM_TYPE) (f * 60.0 + atof(short2str(cp + 1))));
1162     case 'h':
1163 	if (lp->limconst != RLIMIT_CPU)
1164 	    goto badscal;
1165 	limtail(cp, "hours");
1166 	f *= 3600.0;
1167 	break;
1168     case 'm':
1169 	if (lp->limconst == RLIMIT_CPU) {
1170 	    limtail(cp, "minutes");
1171 	    f *= 60.0;
1172 	    break;
1173 	}
1174 	*cp = 'm';
1175 	limtail(cp, "megabytes");
1176 	f *= 1024.0 * 1024.0;
1177 	break;
1178     case 's':
1179 	if (lp->limconst != RLIMIT_CPU)
1180 	    goto badscal;
1181 	limtail(cp, "seconds");
1182 	break;
1183     case 'M':
1184 	if (lp->limconst == RLIMIT_CPU)
1185 	    goto badscal;
1186 	*cp = 'm';
1187 	limtail(cp, "megabytes");
1188 	f *= 1024.0 * 1024.0;
1189 	break;
1190     case 'k':
1191 	if (lp->limconst == RLIMIT_CPU)
1192 	    goto badscal;
1193 	limtail(cp, "kbytes");
1194 	f *= 1024.0;
1195 	break;
1196     case 'u':
1197 	limtail(cp, "unlimited");
1198 	return (RLIM_INFINITY);
1199     default:
1200 badscal:
1201 	stderror(ERR_NAME | ERR_SCALEF);
1202     }
1203     f += 0.5;
1204     if (f > (float) RLIM_INFINITY)
1205 	return RLIM_INFINITY;
1206     else
1207 	return ((RLIM_TYPE) f);
1208 }
1209 
1210 static void
1211 limtail(Char *cp, char *str)
1212 {
1213     char *origstr = str;
1214 
1215     while (*cp && *cp == *str)
1216 	cp++, str++;
1217     if (*cp)
1218 	stderror(ERR_BADSCALE, origstr);
1219 }
1220 
1221 /*ARGSUSED*/
1222 static void
1223 plim(struct limits *lp, Char hard)
1224 {
1225     struct rlimit rlim;
1226     RLIM_TYPE limit;
1227 
1228     (void) fprintf(cshout, "%s \t", lp->limname);
1229 
1230     (void) getrlimit(lp->limconst, &rlim);
1231     limit = hard ? rlim.rlim_max : rlim.rlim_cur;
1232 
1233     if (limit == RLIM_INFINITY)
1234 	(void) fprintf(cshout, "unlimited");
1235     else if (lp->limconst == RLIMIT_CPU)
1236 	psecs((long) limit);
1237     else
1238 	(void) fprintf(cshout, "%ld %s", (long) (limit / lp->limdiv),
1239 		       lp->limscale);
1240     (void) fputc('\n', cshout);
1241 }
1242 
1243 void
1244 /*ARGSUSED*/
1245 dounlimit(Char **v, struct command *t)
1246 {
1247     struct limits *lp;
1248     int     lerr = 0;
1249     Char    hard = 0;
1250 
1251     v++;
1252     if (*v && eq(*v, STRmh)) {
1253 	hard = 1;
1254 	v++;
1255     }
1256     if (*v == 0) {
1257 	for (lp = limits; lp->limconst >= 0; lp++)
1258 	    if (setlim(lp, hard, (RLIM_TYPE) RLIM_INFINITY) < 0)
1259 		lerr++;
1260 	if (lerr)
1261 	    stderror(ERR_SILENT);
1262 	return;
1263     }
1264     while (*v) {
1265 	lp = findlim(*v++);
1266 	if (setlim(lp, hard, (RLIM_TYPE) RLIM_INFINITY) < 0)
1267 	    stderror(ERR_SILENT);
1268     }
1269 }
1270 
1271 static int
1272 setlim(struct limits *lp, Char hard, RLIM_TYPE limit)
1273 {
1274     struct rlimit rlim;
1275 
1276     (void) getrlimit(lp->limconst, &rlim);
1277 
1278     if (hard)
1279 	rlim.rlim_max = limit;
1280     else if (limit == RLIM_INFINITY && geteuid() != 0)
1281 	rlim.rlim_cur = rlim.rlim_max;
1282     else
1283 	rlim.rlim_cur = limit;
1284 
1285     if (setrlimit(lp->limconst, &rlim) < 0) {
1286 	(void) fprintf(csherr, "%s: %s: Can't %s%s limit\n", bname, lp->limname,
1287 		       limit == RLIM_INFINITY ? "remove" : "set",
1288 		       hard ? " hard" : "");
1289 	return (-1);
1290     }
1291     return (0);
1292 }
1293 
1294 void
1295 /*ARGSUSED*/
1296 dosuspend(Char **v, struct command *t)
1297 {
1298     int     ctpgrp;
1299 
1300     void    (*old) (int);
1301 
1302     if (loginsh)
1303 	stderror(ERR_SUSPLOG);
1304     untty();
1305 
1306     old = signal(SIGTSTP, SIG_DFL);
1307     (void) kill(0, SIGTSTP);
1308     /* the shell stops here */
1309     (void) signal(SIGTSTP, old);
1310 
1311     if (tpgrp != -1) {
1312 retry:
1313 	ctpgrp = tcgetpgrp(FSHTTY);
1314       if  (ctpgrp != opgrp) {
1315 	    old = signal(SIGTTIN, SIG_DFL);
1316 	    (void) kill(0, SIGTTIN);
1317 	    (void) signal(SIGTTIN, old);
1318 	  goto retry;
1319 	}
1320 	(void) setpgid(0, shpgrp);
1321 	(void) tcsetpgrp(FSHTTY, shpgrp);
1322     }
1323 }
1324 
1325 /* This is the dreaded EVAL built-in.
1326  *   If you don't fiddle with file descriptors, and reset didfds,
1327  *   this command will either ignore redirection inside or outside
1328  *   its arguments, e.g. eval "date >x"  vs.  eval "date" >x
1329  *   The stuff here seems to work, but I did it by trial and error rather
1330  *   than really knowing what was going on.  If tpgrp is zero, we are
1331  *   probably a background eval, e.g. "eval date &", and we want to
1332  *   make sure that any processes we start stay in our pgrp.
1333  *   This is also the case for "time eval date" -- stay in same pgrp.
1334  *   Otherwise, under stty tostop, processes will stop in the wrong
1335  *   pgrp, with no way for the shell to get them going again.  -IAN!
1336  */
1337 
1338 static Char **gv = NULL;
1339 
1340 void
1341 /*ARGSUSED*/
1342 doeval(Char **v, struct command *t)
1343 {
1344     Char  **oevalvec;
1345     Char   *oevalp;
1346     int     odidfds;
1347     jmp_buf osetexit;
1348     int     my_reenter;
1349     Char  **savegv = gv;
1350     int     saveIN;
1351     int     saveOUT;
1352     int     saveERR;
1353     int     oSHIN;
1354     int     oSHOUT;
1355     int     oSHERR;
1356 
1357     UNREGISTER(v);
1358 
1359     oevalvec = evalvec;
1360     oevalp = evalp;
1361     odidfds = didfds;
1362     oSHIN = SHIN;
1363     oSHOUT = SHOUT;
1364     oSHERR = SHERR;
1365 
1366     v++;
1367     if (*v == 0)
1368 	return;
1369     gflag = 0, tglob(v);
1370     if (gflag) {
1371 	gv = v = globall(v);
1372 	gargv = 0;
1373 	if (v == 0)
1374 	    stderror(ERR_NOMATCH);
1375 	v = copyblk(v);
1376     }
1377     else {
1378 	gv = NULL;
1379 	v = copyblk(v);
1380 	trim(v);
1381     }
1382 
1383     saveIN = dcopy(SHIN, -1);
1384     saveOUT = dcopy(SHOUT, -1);
1385     saveERR = dcopy(SHERR, -1);
1386 
1387     getexit(osetexit);
1388 
1389     if ((my_reenter = setexit()) == 0) {
1390 	evalvec = v;
1391 	evalp = 0;
1392 	SHIN = dcopy(0, -1);
1393 	SHOUT = dcopy(1, -1);
1394 	SHERR = dcopy(2, -1);
1395 	didfds = 0;
1396 	process(0);
1397     }
1398 
1399     evalvec = oevalvec;
1400     evalp = oevalp;
1401     doneinp = 0;
1402     didfds = odidfds;
1403     (void) close(SHIN);
1404     (void) close(SHOUT);
1405     (void) close(SHERR);
1406     SHIN = dmove(saveIN, oSHIN);
1407     SHOUT = dmove(saveOUT, oSHOUT);
1408     SHERR = dmove(saveERR, oSHERR);
1409     if (gv)
1410 	blkfree(gv), gv = NULL;
1411     resexit(osetexit);
1412     gv = savegv;
1413     if (my_reenter)
1414 	stderror(ERR_SILENT);
1415 }
1416