xref: /illumos-gate/usr/src/cmd/csh/sh.set.c (revision 258f91c6)
1 /*
2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved  	*/
8 
9 /*
10  * Copyright (c) 1980 Regents of the University of California.
11  * All rights reserved. The Berkeley Software License Agreement
12  * specifies the terms and conditions for redistribution.
13  */
14 
15 #include "sh.h"
16 #include "sh.tconst.h"
17 
18 /*
19  * C Shell
20  */
21 
22 void	asx(tchar *, int, tchar *);
23 void	putn1(int);
24 void	set(tchar *, tchar *);
25 void	set1(tchar *, tchar **, struct varent *);
26 void	setq(tchar *, tchar **, struct varent *);
27 void	unset1(tchar *[], struct varent *);
28 void	unsetv1(struct varent *);
29 void	exportpath(tchar **);
30 void	balance(struct varent *, int, int);
31 tchar	*operate(tchar, tchar *, tchar *);
32 tchar	*getinx(tchar *, int *);
33 tchar	*xset(tchar *, tchar ***);
34 struct varent	*getvx(tchar *, int);
35 
36 void
doset(tchar ** v)37 doset(tchar **v)
38 {
39 	tchar *p;
40 	tchar *vp, op;
41 	tchar **vecp;
42 	bool hadsub;
43 	int subscr;
44 	tchar *retp;
45 
46 #ifdef TRACE
47 	tprintf("TRACE- doset()\n");
48 #endif
49 	v++;
50 	p = *v++;
51 	if (p == 0) {
52 		prvars();
53 		return;
54 	}
55 	do {
56 		hadsub = 0;
57 		/*
58 		 * check for proper variable syntax
59 		 * must be alphanumeric, start with a letter and
60 		 * be at most 20 characters
61 		 */
62 		for (vp = p; alnum(*p); p++)
63 			continue;
64 		if (vp == p || !letter(*vp))
65 			goto setsyn;
66 		if ((p - vp) > MAX_VAR_LEN)
67 			bferr("Variable name too long");
68 		if (*p == '[') {
69 			hadsub++;
70 			p = getinx(p, &subscr);
71 		}
72 		if (op = *p) {
73 			*p++ = 0;
74 			if (*p == 0 && *v && **v == '(')
75 				p = *v++;
76 		} else if (*v && eq(*v, S_EQ /* "=" */)) {
77 			op = '=', v++;
78 			if (*v)
79 				p = *v++;
80 		}
81 		if (op && op != '=')
82 setsyn:
83 			bferr("Syntax error");
84 		if (eq(p, S_LPAR /* "(" */)) {
85 			tchar **e = v;
86 
87 			if (hadsub)
88 				goto setsyn;
89 			for (;;) {
90 				if (!*e)
91 					bferr("Missing )");
92 				if (**e == ')')
93 					break;
94 				e++;
95 			}
96 			p = *e;
97 			*e = 0;
98 			vecp = saveblk(v);
99 			set1(vp, vecp, &shvhed);
100 			*e = p;
101 			v = e + 1;
102 		} else if (hadsub) {
103 			retp = savestr(p);
104 			asx(vp, subscr, retp);
105 			xfree(retp);
106 			retp = 0;
107 		} else
108 			set(vp, savestr(p));
109 		if (eq(vp, S_path /* "path" */)) {
110 			exportpath(adrof(S_path /* "path" */)->vec);
111 			dohash(xhash);
112 		} else if (eq(vp, S_histchars /* "histchars" */)) {
113 			tchar *p = value(S_histchars /* "histchars" */);
114 			HIST = *p++;
115 			HISTSUB = *p;
116 		} else if (eq(vp, S_user /* "user" */))
117 			local_setenv(S_USER /* "USER" */, value(vp));
118 		else if (eq(vp, S_term /* "term" */))
119 			local_setenv(S_TERM /* "TERM" */, value(vp));
120 		else if (eq(vp, S_home /* "home" */))
121 			local_setenv(S_HOME /* "HOME" */, value(vp));
122 #ifdef FILEC
123 		else if (eq(vp, S_filec /* "filec" */))
124 			filec = 1;
125 		else if (eq(vp, S_cdpath /* "cdpath" */))
126 			dohash(xhash2);
127 #endif
128 	} while (p = *v++);
129 }
130 
131 tchar *
getinx(tchar * cp,int * ip)132 getinx(tchar *cp, int *ip)
133 {
134 
135 #ifdef TRACE
136 	tprintf("TRACE- getinx()\n");
137 #endif
138 	*ip = 0;
139 	*cp++ = 0;
140 	while (*cp && digit(*cp))
141 		*ip = *ip * 10 + *cp++ - '0';
142 	if (*cp++ != ']')
143 		bferr("Subscript error");
144 	return (cp);
145 }
146 
147 void
asx(tchar * vp,int subscr,tchar * p)148 asx(tchar *vp, int subscr, tchar *p)
149 {
150 	struct varent *v = getvx(vp, subscr);
151 
152 #ifdef TRACE
153 	tprintf("TRACE- asx()\n");
154 #endif
155 	xfree(v->vec[subscr - 1]);
156 	v->vec[subscr - 1] = globone(p);
157 }
158 
159 struct varent *
getvx(tchar * vp,int subscr)160 getvx(tchar *vp, int subscr)
161 {
162 	struct varent *v = adrof(vp);
163 
164 #ifdef TRACE
165 	tprintf("TRACE- getvx()\n");
166 #endif
167 	if (v == 0)
168 		udvar(vp);
169 	if (subscr < 1 || subscr > blklen(v->vec))
170 		bferr("Subscript out of range");
171 	return (v);
172 }
173 
174 tchar plusplus[2] = { '1', 0 };
175 
176 void
dolet(tchar ** v)177 dolet(tchar **v)
178 {
179 	tchar *p;
180 	tchar *vp, c, op;
181 	bool hadsub;
182 	int subscr;
183 
184 	v++;
185 	p = *v++;
186 	if (p == 0) {
187 		prvars();
188 		return;
189 	}
190 	do {
191 		hadsub = 0;
192 		for (vp = p; alnum(*p); p++)
193 			continue;
194 		if (vp == p || !letter(*vp))
195 			goto letsyn;
196 		if (*p == '[') {
197 			hadsub++;
198 			p = getinx(p, &subscr);
199 		}
200 		if (*p == 0 && *v)
201 			p = *v++;
202 		if (op = *p)
203 			*p++ = 0;
204 		else
205 			goto letsyn;
206 		vp = savestr(vp);
207 		if (op == '=') {
208 			c = '=';
209 			p = xset(p, &v);
210 		} else {
211 			c = *p++;
212 			/* if (any(c, "+-")) { */
213 			if (c == '+' || c == '-') {
214 				if (c != op || *p)
215 					goto letsyn;
216 				p = plusplus;
217 			} else {
218 				/* if (any(op, "<>")) { */
219 				if (op == '<' || op == '>') {
220 					if (c != op)
221 						goto letsyn;
222 					c = *p++;
223 letsyn:
224 					bferr("Syntax error");
225 				}
226 				if (c != '=')
227 					goto letsyn;
228 				p = xset(p, &v);
229 			}
230 		}
231 		if (op == '=')
232 			if (hadsub)
233 				asx(vp, subscr, p);
234 			else
235 				set(vp, p);
236 		else
237 			if (hadsub)
238 #ifndef V6
239 				/* avoid bug in vax CC */
240 				{
241 					struct varent *gv = getvx(vp, subscr);
242 
243 					asx(vp, subscr, operate(op, gv->vec[subscr - 1], p));
244 				}
245 #else
246 				asx(vp, subscr, operate(op, getvx(vp, subscr)->vec[subscr - 1], p));
247 #endif
248 			else
249 				set(vp, operate(op, value(vp), p));
250 		if (eq(vp, S_path /* "path" */)) {
251 			exportpath(adrof(S_path /* "path" */)->vec);
252 			dohash(xhash);
253 		}
254 
255 		if (eq(vp, S_cdpath /* "cdpath" */))
256 			dohash(xhash2);
257 
258 		xfree(vp);
259 		if (c != '=')
260 			xfree(p);
261 	} while (p = *v++);
262 }
263 
264 tchar *
xset(tchar * cp,tchar *** vp)265 xset(tchar *cp, tchar ***vp)
266 {
267 	tchar *dp;
268 
269 #ifdef TRACE
270 	tprintf("TRACE- xset()\n");
271 #endif
272 	if (*cp) {
273 		dp = savestr(cp);
274 		--(*vp);
275 		xfree(**vp);
276 		**vp = dp;
277 	}
278 	return (putn(exp(vp)));
279 }
280 
281 tchar *
operate(tchar op,tchar * vp,tchar * p)282 operate(tchar op, tchar *vp, tchar *p)
283 {
284 	tchar opr[2];
285 	tchar *vec[5];
286 	tchar **v = vec;
287 	tchar **vecp = v;
288 	int i;
289 
290 	if (op != '=') {
291 		if (*vp)
292 			*v++ = vp;
293 		opr[0] = op;
294 		opr[1] = 0;
295 		*v++ = opr;
296 		if (op == '<' || op == '>')
297 			*v++ = opr;
298 	}
299 	*v++ = p;
300 	*v++ = 0;
301 	i = exp(&vecp);
302 	if (*vecp)
303 		bferr("Expression syntax");
304 	return (putn(i));
305 }
306 
307 static tchar *putp;
308 
309 tchar *
putn(int n)310 putn(int n)
311 {
312 	static tchar number[15];
313 
314 #ifdef TRACE
315 	tprintf("TRACE- putn()\n");
316 #endif
317 	putp = number;
318 	if (n < 0) {
319 		n = -n;
320 		*putp++ = '-';
321 	}
322 	if (sizeof (int) == 2 && n == -32768) {
323 		*putp++ = '3';
324 		n = 2768;
325 #ifdef pdp11
326 	}
327 #else
328 	} else if (sizeof (int) == 4 && n == 0x80000000) {
329 		*putp++ = '2';
330 		n = 147483648;
331 	}
332 #endif
333 	putn1(n);
334 	*putp = 0;
335 	return (savestr(number));
336 }
337 
338 void
putn1(int n)339 putn1(int n)
340 {
341 #ifdef TRACE
342 	tprintf("TRACE- putn1()\n");
343 #endif
344 	if (n > 9)
345 		putn1(n / 10);
346 	*putp++ = n % 10 + '0';
347 }
348 
349 int
getn(tchar * cp)350 getn(tchar *cp)
351 {
352 	int n;
353 	int sign;
354 
355 #ifdef TRACE
356 	tprintf("TRACE- getn()\n");
357 #endif
358 	sign = 0;
359 	if (cp[0] == '+' && cp[1])
360 		cp++;
361 	if (*cp == '-') {
362 		sign++;
363 		cp++;
364 		if (!digit(*cp))
365 			goto badnum;
366 	}
367 	n = 0;
368 	while (digit(*cp))
369 		n = n * 10 + *cp++ - '0';
370 	if (*cp)
371 		goto badnum;
372 	return (sign ? -n : n);
373 badnum:
374 	bferr("Badly formed number");
375 	return (0);
376 }
377 
378 tchar *
value1(tchar * var,struct varent * head)379 value1(tchar *var, struct varent *head)
380 {
381 	struct varent *vp;
382 
383 #ifdef TRACE
384 	tprintf("TRACE- value1()\n");
385 #endif
386 	vp = adrof1(var, head);
387 	return (vp == 0 || vp->vec[0] == 0 ? S_ /* "" */ : vp->vec[0]);
388 }
389 
390 struct varent *
madrof(tchar * pat,struct varent * vp)391 madrof(tchar *pat, struct varent *vp)
392 {
393 	struct varent *vp1;
394 
395 #ifdef TRACE
396 	tprintf("TRACE- madrof()\n");
397 #endif
398 	for (; vp; vp = vp->v_right) {
399 		if (vp->v_left && (vp1 = madrof(pat, vp->v_left)))
400 			return vp1;
401 		if (Gmatch(vp->v_name, pat))
402 			return vp;
403 	}
404 	return vp;
405 }
406 
407 struct varent *
adrof1(tchar * name,struct varent * v)408 adrof1(tchar *name, struct varent *v)
409 {
410 	int cmp;
411 
412 #ifdef TRACE
413 	tprintf("TRACE- adrof1()\n");
414 #endif
415 	v = v->v_left;
416 	while (v && ((cmp = *name - *v->v_name) ||
417 	    (cmp = strcmp_(name, v->v_name))))
418 		if (cmp < 0)
419 			v = v->v_left;
420 		else
421 			v = v->v_right;
422 	return v;
423 }
424 
425 /*
426  * The caller is responsible for putting value in a safe place
427  */
428 void
set(tchar * var,tchar * val)429 set(tchar *var, tchar *val)
430 {
431 	tchar **vec =  (tchar **)xalloc(2 * sizeof (tchar **));
432 
433 #ifdef TRACE
434 	tprintf("TRACE- set()\n");
435 #endif
436 	vec[0] = onlyread(val) ? savestr(val) : val;
437 	vec[1] = 0;
438 	set1(var, vec, &shvhed);
439 }
440 
441 void
set1(tchar * var,tchar ** vec,struct varent * head)442 set1(tchar *var, tchar **vec, struct varent *head)
443 {
444 	tchar **oldv = vec;
445 
446 #ifdef TRACE
447 	tprintf("TRACE- set1()\n");
448 #endif
449 	gflag = 0;
450 	/*
451 	 * If setting cwd variable via "set cwd=/tmp/something"
452 	 * then do globbing.  But if we are setting the cwd
453 	 * becuz of a cd, chdir, pushd, popd, do not do globbing.
454 	 */
455 	if ((!(eq(var, S_cwd))) || (eq(var, S_cwd) && (didchdir == 0)))
456 		{
457 		tglob(oldv);
458 		}
459 	if (gflag) {
460 		vec = glob(oldv);
461 		if (vec == 0) {
462 			bferr("No match");
463 			blkfree(oldv);
464 			return;
465 		}
466 		blkfree(oldv);
467 		gargv = 0;
468 	}
469 	setq(var, vec, head);
470 }
471 
472 void
setq(tchar * name,tchar ** vec,struct varent * p)473 setq(tchar *name, tchar **vec, struct varent *p)
474 {
475 	struct varent *c;
476 	int f;
477 
478 #ifdef TRACE
479 	tprintf("TRACE- setq()\n");
480 #endif
481 	f = 0;			/* tree hangs off the header's left link */
482 	while (c = p->v_link[f]) {
483 		if ((f = *name - *c->v_name) == 0 &&
484 		    (f = strcmp_(name, c->v_name)) == 0) {
485 			blkfree(c->vec);
486 			goto found;
487 		}
488 		p = c;
489 		f = f > 0;
490 	}
491 	p->v_link[f] = c = (struct varent *)xalloc(sizeof (struct varent));
492 	c->v_name = savestr(name);
493 	c->v_bal = 0;
494 	c->v_left = c->v_right = 0;
495 	c->v_parent = p;
496 	balance(p, f, 0);
497 found:
498 	trim(c->vec = vec);
499 }
500 
501 void
unset(tchar * v[])502 unset(tchar *v[])
503 {
504 
505 #ifdef TRACE
506 	tprintf("TRACE- unset()\n");
507 #endif
508 	unset1(v, &shvhed);
509 	if (adrof(S_histchars /* "histchars" */) == 0) {
510 		HIST = '!';
511 		HISTSUB = '^';
512 	}
513 #ifdef FILEC
514 	if (adrof(S_filec /* "filec" */) == 0)
515 		filec = 0;
516 #endif
517 }
518 
519 void
unset1(tchar * v[],struct varent * head)520 unset1(tchar *v[], struct varent *head)
521 {
522 	struct varent *vp;
523 	int cnt;
524 
525 #ifdef TRACE
526 	tprintf("TRACE- unset1()\n");
527 #endif
528 	while (*++v) {
529 		cnt = 0;
530 		while (vp = madrof(*v, head->v_left))
531 			unsetv1(vp), cnt++;
532 		if (cnt == 0)
533 			setname(*v);
534 	}
535 }
536 
537 void
unsetv(tchar * var)538 unsetv(tchar *var)
539 {
540 	struct varent *vp;
541 
542 #ifdef TRACE
543 	tprintf("TRACE- unsetv()\n");
544 #endif
545 	if ((vp = adrof1(var, &shvhed)) == 0)
546 		udvar(var);
547 	unsetv1(vp);
548 }
549 
550 void
unsetv1(struct varent * p)551 unsetv1(struct varent *p)
552 {
553 	struct varent *c, *pp;
554 	int f;
555 
556 #ifdef TRACE
557 	tprintf("TRACE- unsetv1()\n");
558 #endif
559 	/*
560 	 * Free associated memory first to avoid complications.
561 	 */
562 	blkfree(p->vec);
563 	xfree(p->v_name);
564 	/*
565 	 * If p is missing one child, then we can move the other
566 	 * into where p is.  Otherwise, we find the predecessor
567 	 * of p, which is guaranteed to have no right child, copy
568 	 * it into p, and move it's left child into it.
569 	 */
570 	if (p->v_right == 0)
571 		c = p->v_left;
572 	else if (p->v_left == 0)
573 		c = p->v_right;
574 	else {
575 		for (c = p->v_left; c->v_right; c = c->v_right)
576 			;
577 		p->v_name = c->v_name;
578 		p->vec = c->vec;
579 		p = c;
580 		c = p->v_left;
581 	}
582 	/*
583 	 * Move c into where p is.
584 	 */
585 	pp = p->v_parent;
586 	f = pp->v_right == p;
587 	if (pp->v_link[f] = c)
588 		c->v_parent = pp;
589 	/*
590 	 * Free the deleted node, and rebalance.
591 	 */
592 	xfree(p);
593 	balance(pp, f, 1);
594 }
595 
596 void
setNS(tchar * cp)597 setNS(tchar *cp)
598 {
599 #ifdef TRACE
600 	tprintf("TRACE- setNS()\n");
601 #endif
602 
603 	set(cp, S_ /* "" */);
604 }
605 
606 void
shift(tchar ** v)607 shift(tchar **v)
608 {
609 	struct varent *argv;
610 	tchar *name;
611 
612 #ifdef TRACE
613 	tprintf("TRACE- shift()\n");
614 #endif
615 	v++;
616 	name = *v;
617 	if (name == 0)
618 		name = S_argv /* "argv" */;
619 	else
620 		(void) strip(name);
621 	argv = adrof(name);
622 	if (argv == 0)
623 		udvar(name);
624 	if (argv->vec[0] == 0)
625 		bferr("No more words");
626 	lshift(argv->vec, 1);
627 }
628 
629 void
exportpath(tchar ** val)630 exportpath(tchar **val)
631 {
632 	tchar exppath[PATHSIZ];
633 
634 #ifdef TRACE
635 	tprintf("TRACE- exportpath()\n");
636 #endif
637 	exppath[0] = 0;
638 	if (val)
639 		while (*val) {
640 			if (strlen_(*val) + strlen_(exppath) + 2 > PATHSIZ) {
641 				printf("Warning: ridiculously long PATH truncated\n");
642 				break;
643 			}
644 			(void) strcat_(exppath, *val++);
645 			if (*val == 0 || eq(*val, S_RPAR /* ")" */))
646 				break;
647 			(void) strcat_(exppath, S_COLON /* ":" */);
648 		}
649 	local_setenv(S_PATH /* "PATH" */, exppath);
650 }
651 
652 	/* macros to do single rotations on node p */
653 #define	rright(p) (\
654 	t = (p)->v_left,\
655 	(t)->v_parent = (p)->v_parent,\
656 	((p)->v_left = t->v_right) ? (t->v_right->v_parent = (p)) : 0,\
657 	(t->v_right = (p))->v_parent = t,\
658 	(p) = t)
659 #define	rleft(p) (\
660 	t = (p)->v_right,\
661 	(t)->v_parent = (p)->v_parent,\
662 	((p)->v_right = t->v_left) ? (t->v_left->v_parent = (p)) : 0,\
663 	(t->v_left = (p))->v_parent = t,\
664 	(p) = t)
665 
666 /*
667  * Rebalance a tree, starting at p and up.
668  * F == 0 means we've come from p's left child.
669  * D == 1 means we've just done a delete, otherwise an insert.
670  */
671 void
balance(struct varent * p,int f,int d)672 balance(struct varent *p, int f, int d)
673 {
674 	struct varent *pp;
675 	struct varent *t;		/* used by the rotate macros */
676 	int ff;
677 
678 #ifdef TRACE
679 	tprintf("TRACE- balance()\n");
680 #endif
681 	/*
682 	 * Ok, from here on, p is the node we're operating on;
683 	 * pp is it's parent; f is the branch of p from which we have come;
684 	 * ff is the branch of pp which is p.
685 	 */
686 	for (; pp = p->v_parent; p = pp, f = ff) {
687 		ff = pp->v_right == p;
688 		if (f ^ d) {		/* right heavy */
689 			switch (p->v_bal) {
690 			case -1:		/* was left heavy */
691 				p->v_bal = 0;
692 				break;
693 			case 0:			/* was balanced */
694 				p->v_bal = 1;
695 				break;
696 			case 1:			/* was already right heavy */
697 				switch (p->v_right->v_bal) {
698 				case 1:			/* sigle rotate */
699 					pp->v_link[ff] = rleft(p);
700 					p->v_left->v_bal = 0;
701 					p->v_bal = 0;
702 					break;
703 				case 0:			/* single rotate */
704 					pp->v_link[ff] = rleft(p);
705 					p->v_left->v_bal = 1;
706 					p->v_bal = -1;
707 					break;
708 				case -1:		/* double rotate */
709 					rright(p->v_right);
710 					pp->v_link[ff] = rleft(p);
711 					p->v_left->v_bal =
712 						p->v_bal < 1 ? 0 : -1;
713 					p->v_right->v_bal =
714 						p->v_bal > -1 ? 0 : 1;
715 					p->v_bal = 0;
716 					break;
717 				}
718 				break;
719 			}
720 		} else {		/* left heavy */
721 			switch (p->v_bal) {
722 			case 1:			/* was right heavy */
723 				p->v_bal = 0;
724 				break;
725 			case 0:			/* was balanced */
726 				p->v_bal = -1;
727 				break;
728 			case -1:		/* was already left heavy */
729 				switch (p->v_left->v_bal) {
730 				case -1:		/* single rotate */
731 					pp->v_link[ff] = rright(p);
732 					p->v_right->v_bal = 0;
733 					p->v_bal = 0;
734 					break;
735 				case 0:			/* signle rotate */
736 					pp->v_link[ff] = rright(p);
737 					p->v_right->v_bal = -1;
738 					p->v_bal = 1;
739 					break;
740 				case 1:			/* double rotate */
741 					rleft(p->v_left);
742 					pp->v_link[ff] = rright(p);
743 					p->v_left->v_bal =
744 						p->v_bal < 1 ? 0 : -1;
745 					p->v_right->v_bal =
746 						p->v_bal > -1 ? 0 : 1;
747 					p->v_bal = 0;
748 					break;
749 				}
750 				break;
751 			}
752 		}
753 		/*
754 		 * If from insert, then we terminate when p is balanced.
755 		 * If from delete, then we terminate when p is unbalanced.
756 		 */
757 		if ((p->v_bal == 0) ^ d)
758 			break;
759 	}
760 }
761 
762 void
plist(struct varent * p)763 plist(struct varent *p)
764 {
765 	struct varent *c;
766 	int len;
767 
768 #ifdef TRACE
769 	tprintf("TRACE- plist()\n");
770 #endif
771 	if (setintr)
772 		(void) sigsetmask(sigblock(0) & ~ sigmask(SIGINT));
773 	for (;;) {
774 		while (p->v_left)
775 			p = p->v_left;
776 	x:
777 		if (p->v_parent == 0)		/* is it the header? */
778 			return;
779 		len = blklen(p->vec);
780 		printf("%t", p->v_name);
781 		Putchar('\t');
782 		if (len != 1)
783 			Putchar('(');
784 		blkpr(p->vec);
785 		if (len != 1)
786 			Putchar(')');
787 		Putchar('\n');
788 		if (p->v_right) {
789 			p = p->v_right;
790 			continue;
791 		}
792 		do {
793 			c = p;
794 			p = p->v_parent;
795 		} while (p->v_right == c);
796 		goto x;
797 	}
798 }
799