1 #include "sh.h"
2 #include "ksh_time.h"
3 #include "ksh_limval.h"
4 #include "ksh_stat.h"
5 #include <ctype.h>
6
7 /*
8 * Variables
9 *
10 * WARNING: unreadable code, needs a rewrite
11 *
12 * if (flag&INTEGER), val.i contains integer value, and type contains base.
13 * otherwise, (val.s + type) contains string value.
14 * if (flag&EXPORT), val.s contains "name=value" for E-Z exporting.
15 */
16 static struct tbl vtemp;
17 static struct table specials;
18 static char *formatstr ARGS((struct tbl *vp, const char *s));
19 static void export ARGS((struct tbl *vp, const char *val));
20 static int special ARGS((const char *name));
21 static void unspecial ARGS((const char *name));
22 static void getspec ARGS((struct tbl *vp));
23 static void setspec ARGS((struct tbl *vp));
24 static void unsetspec ARGS((struct tbl *vp));
25 static struct tbl *arraysearch ARGS((struct tbl *, int));
26
27 /*
28 * create a new block for function calls and simple commands
29 * assume caller has allocated and set up e->loc
30 */
31 void
newblock()32 newblock()
33 {
34 register struct block *l;
35 static char *const empty[] = {null};
36
37 l = (struct block *) alloc(sizeof(struct block), ATEMP);
38 l->flags = 0;
39 ainit(&l->area); /* todo: could use e->area (l->area => l->areap) */
40 if (!e->loc) {
41 l->argc = 0;
42 l->argv = (char **) empty;
43 } else {
44 l->argc = e->loc->argc;
45 l->argv = e->loc->argv;
46 }
47 l->exit = l->error = NULL;
48 tinit(&l->vars, &l->area, 0);
49 tinit(&l->funs, &l->area, 0);
50 l->next = e->loc;
51 e->loc = l;
52 }
53
54 /*
55 * pop a block handling special variables
56 */
57 void
popblock()58 popblock()
59 {
60 register struct block *l = e->loc;
61 register struct tbl *vp, **vpp = l->vars.tbls, *vq;
62 register int i;
63
64 e->loc = l->next; /* pop block */
65 for (i = l->vars.size; --i >= 0; )
66 if ((vp = *vpp++) != NULL && (vp->flag&SPECIAL))
67 if ((vq = global(vp->name))->flag & ISSET)
68 setspec(vq);
69 else
70 unsetspec(vq);
71 if (l->flags & BF_DOGETOPTS)
72 user_opt = l->getopts_state;
73 afreeall(&l->area);
74 afree(l, ATEMP);
75 }
76
77 /* called by main() to initialize variable data structures */
78 void
initvar()79 initvar()
80 {
81 static const struct {
82 const char *name;
83 int v;
84 } names[] = {
85 { "COLUMNS", V_COLUMNS },
86 { "IFS", V_IFS },
87 { "OPTIND", V_OPTIND },
88 { "PATH", V_PATH },
89 { "POSIXLY_CORRECT", V_POSIXLY_CORRECT },
90 { "TMPDIR", V_TMPDIR },
91 #ifdef HISTORY
92 { "HISTFILE", V_HISTFILE },
93 { "HISTSIZE", V_HISTSIZE },
94 #endif /* HISTORY */
95 #ifdef EDIT
96 { "EDITOR", V_EDITOR },
97 { "VISUAL", V_VISUAL },
98 #endif /* EDIT */
99 #ifdef KSH
100 { "MAIL", V_MAIL },
101 { "MAILCHECK", V_MAILCHECK },
102 { "MAILPATH", V_MAILPATH },
103 { "RANDOM", V_RANDOM },
104 { "SECONDS", V_SECONDS },
105 { "TMOUT", V_TMOUT },
106 #endif /* KSH */
107 { "LINENO", V_LINENO },
108 { (char *) 0, 0 }
109 };
110 int i;
111 struct tbl *tp;
112
113 tinit(&specials, APERM, 32); /* must be 2^n (currently 17 specials) */
114 for (i = 0; names[i].name; i++) {
115 tp = tenter(&specials, names[i].name, hash(names[i].name));
116 tp->flag = DEFINED|ISSET;
117 tp->type = names[i].v;
118 }
119 }
120
121 /* Used to calculate an array index for global()/local(). Sets *arrayp to
122 * non-zero if this is an array, sets *valp to the array index, returns
123 * the basename of the array.
124 */
125 const char *
array_index_calc(const char * n,bool_t * arrayp,int * valp)126 array_index_calc(const char *n, bool_t *arrayp, int *valp)
127 {
128 const char *p;
129 int len;
130
131 *arrayp = FALSE;
132 p = skip_varname(n, FALSE);
133 if (p != n && *p == '[' && (len = array_ref_len(p))) {
134 char *sub, *tmp;
135 long rval;
136
137 /* Calculate the value of the subscript */
138 *arrayp = TRUE;
139 tmp = str_nsave(p+1, len-2, ATEMP);
140 sub = substitute(tmp, 0);
141 afree(tmp, ATEMP);
142 n = str_nsave(n, p - n, ATEMP);
143 evaluate(sub, &rval, KSH_UNWIND_ERROR);
144 if (rval < 0 || rval > ARRAYMAX)
145 errorf("%s: subscript out of range", n);
146 *valp = rval;
147 afree(sub, ATEMP);
148 }
149 return n;
150 }
151
152 /*
153 * Search for variable, if not found create globally.
154 */
155 struct tbl *
global(n)156 global(n)
157 register const char *n;
158 {
159 register struct block *l = e->loc;
160 register struct tbl *vp;
161 register int c;
162 unsigned h;
163 bool_t array;
164 int val;
165
166 /* Check to see if this is an array */
167 n = array_index_calc(n, &array, &val);
168 h = hash(n);
169 c = n[0];
170 if (!letter(c)) {
171 if (array)
172 errorf("bad substitution");
173 vp = &vtemp;
174 vp->flag = DEFINED;
175 vp->type = 0;
176 vp->areap = ATEMP;
177 *vp->name = c;
178 if (digit(c)) {
179 for (c = 0; digit(*n); n++)
180 c = c*10 + *n-'0';
181 if (c <= l->argc)
182 /* setstr can't fail here */
183 setstr(vp, l->argv[c], KSH_RETURN_ERROR);
184 vp->flag |= RDONLY;
185 return vp;
186 }
187 vp->flag |= RDONLY;
188 if (n[1] != '\0')
189 return vp;
190 vp->flag |= ISSET|INTEGER;
191 switch (c) {
192 case '$':
193 vp->val.i = kshpid;
194 break;
195 case '!':
196 /* If no job, expand to nothing */
197 if ((vp->val.i = j_async()) == 0)
198 vp->flag &= ~(ISSET|INTEGER);
199 break;
200 case '?':
201 vp->val.i = exstat;
202 break;
203 case '#':
204 vp->val.i = l->argc;
205 break;
206 case '-':
207 vp->flag &= ~INTEGER;
208 vp->val.s = getoptions();
209 break;
210 default:
211 vp->flag &= ~(ISSET|INTEGER);
212 }
213 return vp;
214 }
215 for (l = e->loc; ; l = l->next) {
216 vp = tsearch(&l->vars, n, h);
217 if (vp != NULL)
218 if (array)
219 return arraysearch(vp, val);
220 else
221 return vp;
222 if (l->next == NULL)
223 break;
224 }
225 vp = tenter(&l->vars, n, h);
226 if (array)
227 vp = arraysearch(vp, val);
228 vp->flag |= DEFINED;
229 if (special(n))
230 vp->flag |= SPECIAL;
231 return vp;
232 }
233
234 /*
235 * Search for local variable, if not found create locally.
236 */
237 struct tbl *
local(n,copy)238 local(n, copy)
239 register const char *n;
240 bool_t copy;
241 {
242 register struct block *l = e->loc;
243 register struct tbl *vp;
244 unsigned h;
245 bool_t array;
246 int val;
247
248 /* Check to see if this is an array */
249 n = array_index_calc(n, &array, &val);
250 h = hash(n);
251 if (!letter(*n)) {
252 vp = &vtemp;
253 vp->flag = DEFINED|RDONLY;
254 vp->type = 0;
255 vp->areap = ATEMP;
256 return vp;
257 }
258 vp = tenter(&l->vars, n, h);
259 if (copy && !(vp->flag & DEFINED)) {
260 struct block *ll = l;
261 struct tbl *vq = (struct tbl *) 0;
262
263 while ((ll = ll->next) && !(vq = tsearch(&ll->vars, n, h)))
264 ;
265 if (vq) {
266 vp->flag |= vq->flag & (EXPORT|INTEGER|RDONLY
267 |LJUST|RJUST|ZEROFIL
268 |LCASEV|UCASEV_AL|INT_U|INT_L);
269 if (vq->flag & INTEGER)
270 vp->type = vq->type;
271 vp->u2.field = vq->u2.field;
272 }
273 }
274 if (array)
275 vp = arraysearch(vp, val);
276 vp->flag |= DEFINED;
277 if (special(n))
278 vp->flag |= SPECIAL;
279 return vp;
280 }
281
282 /* get variable string value */
283 char *
str_val(vp)284 str_val(vp)
285 register struct tbl *vp;
286 {
287 char *s;
288
289 if ((vp->flag&SPECIAL))
290 getspec(vp);
291 if (!(vp->flag&ISSET))
292 s = null; /* special to dollar() */
293 else if (!(vp->flag&INTEGER)) /* string source */
294 s = vp->val.s + vp->type;
295 else { /* integer source */
296 /* worst case number length is when base=2, so use BITS(long) */
297 /* minus base # number null */
298 static char strbuf[1 + 2 + 1 + BITS(long) + 1];
299 const char *digits = (vp->flag & UCASEV_AL) ?
300 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
301 : "0123456789abcdefghijklmnopqrstuvwxyz";
302 register unsigned long n;
303 register int base;
304
305 s = strbuf + sizeof(strbuf);
306 if (vp->flag & INT_U)
307 n = (unsigned long) vp->val.i;
308 else
309 n = (vp->val.i < 0) ? -vp->val.i : vp->val.i;
310 base = (vp->type == 0) ? 10 : vp->type;
311
312 *--s = '\0';
313 do {
314 *--s = digits[n % base];
315 n /= base;
316 } while (n != 0);
317 if (base != 10) {
318 *--s = '#';
319 *--s = digits[base % 10];
320 if (base >= 10)
321 *--s = digits[base / 10];
322 }
323 if (!(vp->flag & INT_U) && vp->val.i < 0)
324 *--s = '-';
325 if (vp->flag & (RJUST|LJUST)) /* case already dealt with */
326 s = formatstr(vp, s);
327 }
328 return s;
329 }
330
331 /* get variable integer value, with error checking */
332 long
intval(vp)333 intval(vp)
334 register struct tbl *vp;
335 {
336 long num;
337 int base;
338
339 base = getint(vp, &num);
340 if (base == -1)
341 /* XXX check calls - is error here ok by POSIX? */
342 errorf("%s: bad number", str_val(vp));
343 return num;
344 }
345
346 /* set variable to string value */
347 int
setstr(vq,s,error_ok)348 setstr(vq, s, error_ok)
349 register struct tbl *vq;
350 const char *s;
351 int error_ok;
352 {
353 if (vq->flag & RDONLY) {
354 warningf(TRUE, "%s: is read only", vq->name);
355 if (!error_ok)
356 errorf(null);
357 return 0;
358 }
359 if (!(vq->flag&INTEGER)) { /* string dest */
360 if ((vq->flag&ALLOC)) {
361 /* debugging */
362 if (s >= vq->val.s
363 && s <= vq->val.s + strlen(vq->val.s))
364 internal_errorf(TRUE,
365 "setstr: %s=%s: assigning to self",
366 vq->name, s);
367 afree((void*)vq->val.s, vq->areap);
368 }
369 vq->flag &= ~(ISSET|ALLOC);
370 vq->type = 0;
371 if (s && (vq->flag & (UCASEV_AL|LCASEV|LJUST|RJUST)))
372 s = formatstr(vq, s);
373 if ((vq->flag&EXPORT))
374 export(vq, s);
375 else {
376 vq->val.s = str_save(s, vq->areap);
377 if (vq->val.s) /* <sjg> don't lie */
378 vq->flag |= ALLOC;
379 }
380 } else /* integer dest */
381 if (!v_evaluate(vq, s, error_ok))
382 return 0;
383 vq->flag |= ISSET;
384 if ((vq->flag&SPECIAL))
385 setspec(vq);
386 return 1;
387 }
388
389 /* set variable to integer */
390 void
setint(vq,n)391 setint(vq, n)
392 register struct tbl *vq;
393 long n;
394 {
395 if (!(vq->flag&INTEGER)) {
396 register struct tbl *vp = &vtemp;
397 vp->flag = (ISSET|INTEGER);
398 vp->type = 0;
399 vp->areap = ATEMP;
400 vp->val.i = n;
401 /* setstr can't fail here */
402 setstr(vq, str_val(vp), KSH_RETURN_ERROR);
403 } else
404 vq->val.i = n;
405 vq->flag |= ISSET;
406 if ((vq->flag&SPECIAL))
407 setspec(vq);
408 }
409
410 int
getint(vp,nump)411 getint(vp, nump)
412 struct tbl *vp;
413 long *nump;
414 {
415 register char *s;
416 register int c;
417 int base, neg;
418 int have_base = 0;
419 long num;
420
421 if (vp->flag&SPECIAL)
422 getspec(vp);
423 /* XXX is it possible for ISSET to be set and val.s to be 0? */
424 if (!(vp->flag&ISSET) || (!(vp->flag&INTEGER) && vp->val.s == NULL))
425 return -1;
426 if (vp->flag&INTEGER) {
427 *nump = vp->val.i;
428 return vp->type;
429 }
430 s = vp->val.s + vp->type;
431 if (s == NULL) /* redundent given initial test */
432 s = null;
433 base = 10;
434 num = 0;
435 neg = 0;
436 for (c = *s++; c ; c = *s++) {
437 if (c == '-') {
438 neg++;
439 } else if (c == '#') {
440 base = (int) num;
441 if (have_base || base < 2 || base > 36)
442 return -1;
443 num = 0;
444 have_base = 1;
445 } else if (letnum(c)) {
446 if (isdigit(c))
447 c -= '0';
448 else if (islower(c))
449 c -= 'a' - 10; /* todo: assumes ascii */
450 else if (isupper(c))
451 c -= 'A' - 10; /* todo: assumes ascii */
452 else
453 c = -1; /* _: force error */
454 if (c < 0 || c >= base)
455 return -1;
456 num = num * base + c;
457 } else
458 return -1;
459 }
460 if (neg)
461 num = -num;
462 *nump = num;
463 return base;
464 }
465
466 /* convert variable vq to integer variable, setting its value from vp
467 * (vq and vp may be the same)
468 */
469 struct tbl *
setint_v(vq,vp)470 setint_v(vq, vp)
471 register struct tbl *vq, *vp;
472 {
473 int base;
474 long num;
475
476 if ((base = getint(vp, &num)) == -1)
477 return NULL;
478 if (!(vq->flag & INTEGER) && (vq->flag & ALLOC)) {
479 vq->flag &= ~ALLOC;
480 afree(vq->val.s, vq->areap);
481 }
482 vq->val.i = num;
483 if (vq->type == 0) /* default base */
484 vq->type = base;
485 vq->flag |= ISSET|INTEGER;
486 if (vq->flag&SPECIAL)
487 setspec(vq);
488 return vq;
489 }
490
491 static char *
formatstr(vp,s)492 formatstr(vp, s)
493 struct tbl *vp;
494 const char *s;
495 {
496 int olen, nlen;
497 char *p, *q;
498
499 olen = strlen(s);
500
501 if (vp->flag & (RJUST|LJUST)) {
502 if (!vp->u2.field) /* default field width */
503 vp->u2.field = olen;
504 nlen = vp->u2.field;
505 } else
506 nlen = olen;
507
508 p = (char *) alloc(nlen + 1, ATEMP);
509 if (vp->flag & (RJUST|LJUST)) {
510 int slen;
511
512 if (vp->flag & RJUST) {
513 const char *q = s + olen;
514 /* strip trailing spaces (at&t ksh uses q[-1] == ' ') */
515 while (q > s && isspace(q[-1]))
516 --q;
517 slen = q - s;
518 if (slen > vp->u2.field) {
519 s += slen - vp->u2.field;
520 slen = vp->u2.field;
521 }
522 shf_snprintf(p, nlen + 1,
523 ((vp->flag & ZEROFIL) && digit(*s)) ?
524 "%0*s%.*s" : "%*s%.*s",
525 vp->u2.field - slen, null, slen, s);
526 } else {
527 /* strip leading spaces/zeros */
528 while (isspace(*s))
529 s++;
530 if (vp->flag & ZEROFIL)
531 while (*s == '0')
532 s++;
533 shf_snprintf(p, nlen + 1, "%-*.*s",
534 vp->u2.field, vp->u2.field, s);
535 }
536 } else
537 memcpy(p, s, olen + 1);
538
539 if (vp->flag & UCASEV_AL) {
540 for (q = p; *q; q++)
541 if (islower(*q))
542 *q = toupper(*q);
543 } else if (vp->flag & LCASEV) {
544 for (q = p; *q; q++)
545 if (isupper(*q))
546 *q = tolower(*q);
547 }
548
549 return p;
550 }
551
552 /*
553 * make vp->val.s be "name=value" for quick exporting.
554 */
555 static void
export(vp,val)556 export(vp, val)
557 register struct tbl *vp;
558 const char *val;
559 {
560 register char *xp;
561 char *op = (vp->flag&ALLOC) ? vp->val.s : NULL;
562 int namelen = strlen(vp->name);
563 int vallen = strlen(val) + 1;
564
565 vp->flag |= ALLOC;
566 xp = (char*)alloc(namelen + 1 + vallen, vp->areap);
567 memcpy(vp->val.s = xp, vp->name, namelen);
568 xp += namelen;
569 *xp++ = '=';
570 vp->type = xp - vp->val.s; /* offset to value */
571 memcpy(xp, val, vallen);
572 if (op != NULL)
573 afree((void*)op, vp->areap);
574 }
575
576 /*
577 * lookup variable (according to (set&LOCAL)),
578 * set its attributes (INTEGER, RDONLY, EXPORT, TRACE, LJUST, RJUST, ZEROFIL,
579 * LCASEV, UCASEV_AL), and optionally set its value if an assignment.
580 */
581 struct tbl *
typeset(var,set,clr,field,base)582 typeset(var, set, clr, field, base)
583 register const char *var;
584 Tflag clr, set;
585 int field, base;
586 {
587 register struct tbl *vp;
588 struct tbl *vpbase, *t;
589 char *tvar;
590 const char *val;
591
592 /* check for valid variable name, search for value */
593 val = skip_varname(var, FALSE);
594 if (val == var)
595 return NULL;
596 if (*val == '[') {
597 int len;
598
599 len = array_ref_len(val);
600 if (len == 0)
601 return NULL;
602 /* IMPORT is only used when the shell starts up and is
603 * setting up its environment. Allow only simple array
604 * references at this time since parameter/command substitution
605 * is preformed on the [expression], which would be a major
606 * security hole.
607 */
608 if (set & IMPORT) {
609 int i;
610 for (i = 1; i < len - 1; i++)
611 if (!digit(val[i]))
612 return NULL;
613 }
614 val += len;
615 }
616 if (*val == '=')
617 tvar = str_nsave(var, val++ - var, ATEMP);
618 else {
619 /* Importing from original envirnment: must have an = */
620 if (set & IMPORT)
621 return NULL;
622 tvar = (char *) var;
623 val = NULL;
624 }
625
626 /* Prevent typeset from creating a local PATH/ENV/SHELL */
627 if (Flag(FRESTRICTED) && (strcmp(tvar, "PATH") == 0
628 || strcmp(tvar, "ENV") == 0
629 || strcmp(tvar, "SHELL") == 0))
630 errorf("%s: restricted", tvar);
631
632 vp = (set&LOCAL) ? local(tvar, (set & LOCAL_COPY) ? TRUE : FALSE)
633 : global(tvar);
634 set &= ~(LOCAL|LOCAL_COPY);
635
636 vpbase = (vp->flag & ARRAY) ? global(arrayname(var)) : vp;
637
638 /* only allow export flag to be set. at&t ksh allows any attribute to
639 * be changed, which means it can be truncated or modified
640 * (-L/-R/-Z/-i).
641 */
642 if ((vpbase->flag&RDONLY)
643 && (val || clr || (set & ~EXPORT)))
644 /* XXX check calls - is error here ok by POSIX? */
645 errorf("%s: is read only", tvar);
646 if (val)
647 afree(tvar, ATEMP);
648
649 /* most calls are with set/clr == 0 */
650 if (set | clr) {
651 int ok = 1;
652 /* XXX if x[0] isn't set, there will be problems: need to have
653 * one copy of attributes for arrays...
654 */
655 for (t = vpbase; t; t = t->u.array) {
656 int fake_assign;
657 char UNINITIALIZED(*s);
658 char UNINITIALIZED(*free_me);
659
660 fake_assign = (t->flag & ISSET) && (!val || t != vp)
661 && ((set & (UCASEV_AL|LCASEV|LJUST|RJUST|ZEROFIL))
662 || ((t->flag & INTEGER) && (clr & INTEGER))
663 || (!(t->flag & INTEGER) && (set & INTEGER)));
664 if (fake_assign) {
665 if (t->flag & INTEGER) {
666 s = str_val(t);
667 free_me = (char *) 0;
668 } else {
669 s = t->val.s + t->type;
670 free_me = (t->flag & ALLOC) ? t->val.s
671 : (char *) 0;
672 }
673 t->flag &= ~ALLOC;
674 }
675 if (!(t->flag & INTEGER) && (set & INTEGER)) {
676 t->type = 0;
677 t->flag &= ~ALLOC;
678 }
679 t->flag = (t->flag | set) & ~clr;
680 /* Don't change base if assignment is to be done,
681 * in case assignment fails.
682 */
683 if ((set & INTEGER) && base > 0 && (!val || t != vp))
684 t->type = base;
685 if (set & (LJUST|RJUST|ZEROFIL))
686 t->u2.field = field;
687 if (fake_assign) {
688 if (!setstr(t, s, KSH_RETURN_ERROR)) {
689 /* Somewhat arbitrary action here:
690 * zap contents of varibale, but keep
691 * the flag settings.
692 */
693 ok = 0;
694 if (t->flag & INTEGER)
695 t->flag &= ~ISSET;
696 else {
697 if (t->flag & ALLOC)
698 afree((void*) t->val.s,
699 t->areap);
700 t->flag &= ~(ISSET|ALLOC);
701 t->type = 0;
702 }
703 }
704 if (free_me)
705 afree((void *) free_me, t->areap);
706 }
707 }
708 if (!ok)
709 errorf(null);
710 }
711
712 if (val != NULL) {
713 if (vp->flag&INTEGER) {
714 /* do not zero base before assignment */
715 setstr(vp, val, KSH_UNWIND_ERROR);
716 /* Done after assignment to override default */
717 if (base > 0)
718 vp->type = base;
719 } else
720 /* setstr can't fail (readonly check already done) */
721 setstr(vp, val, KSH_RETURN_ERROR);
722 }
723
724 /* only x[0] is ever exported, so use vpbase */
725 if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER)
726 && vpbase->type == 0)
727 export(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null);
728
729 return vp;
730 }
731
732 /* Unset a variable. array_ref is set if there was an array reference in
733 * the name lookup (eg, x[2]).
734 */
735 void
unset(vp,array_ref)736 unset(vp, array_ref)
737 register struct tbl *vp;
738 int array_ref;
739 {
740 if (vp->flag & ALLOC)
741 afree((void*)vp->val.s, vp->areap);
742 if ((vp->flag & ARRAY) && !array_ref) {
743 struct tbl *a, *tmp;
744
745 /* Free up entire array */
746 for (a = vp->u.array; a; ) {
747 tmp = a;
748 a = a->u.array;
749 if (tmp->flag & ALLOC)
750 afree((void *) tmp->val.s, tmp->areap);
751 afree(tmp, tmp->areap);
752 }
753 vp->u.array = (struct tbl *) 0;
754 }
755 /* If foo[0] is being unset, the remainder of the array is kept... */
756 vp->flag &= SPECIAL | (array_ref ? ARRAY|DEFINED : 0);
757 if (vp->flag & SPECIAL)
758 unsetspec(vp); /* responsible for `unspecial'ing var */
759 }
760
761 /* return a pointer to the first char past a legal variable name (returns the
762 * argument if there is no legal name, returns * a pointer to the terminating
763 * null if whole string is legal).
764 */
765 char *
skip_varname(s,aok)766 skip_varname(s, aok)
767 const char *s;
768 int aok;
769 {
770 int alen;
771
772 if (s && letter(*s)) {
773 while (*++s && letnum(*s))
774 ;
775 if (aok && *s == '[' && (alen = array_ref_len(s)))
776 s += alen;
777 }
778 return (char *) s;
779 }
780
781 /* Return a pointer to the first character past any legal variable name. */
782 char *
skip_wdvarname(s,aok)783 skip_wdvarname(s, aok)
784 const char *s;
785 int aok; /* skip array de-reference? */
786 {
787 if (s[0] == CHAR && letter(s[1])) {
788 do
789 s += 2;
790 while (s[0] == CHAR && letnum(s[1]));
791 if (aok && s[0] == CHAR && s[1] == '[') {
792 /* skip possible array de-reference */
793 const char *p = s;
794 char c;
795 int depth = 0;
796
797 while (1) {
798 if (p[0] != CHAR)
799 break;
800 c = p[1];
801 p += 2;
802 if (c == '[')
803 depth++;
804 else if (c == ']' && --depth == 0) {
805 s = p;
806 break;
807 }
808 }
809 }
810 }
811 return (char *) s;
812 }
813
814 /* Check if coded string s is a variable name */
815 int
is_wdvarname(s,aok)816 is_wdvarname(s, aok)
817 const char *s;
818 int aok;
819 {
820 char *p = skip_wdvarname(s, aok);
821
822 return p != s && p[0] == EOS;
823 }
824
825 /* Check if coded string s is a variable assignment */
826 int
is_wdvarassign(s)827 is_wdvarassign(s)
828 const char *s;
829 {
830 char *p = skip_wdvarname(s, TRUE);
831
832 return p != s && p[0] == CHAR && p[1] == '=';
833 }
834
835 /*
836 * Make the exported environment from the exported names in the dictionary.
837 */
838 char **
makenv()839 makenv()
840 {
841 struct block *l = e->loc;
842 XPtrV env;
843 register struct tbl *vp, **vpp;
844 register int i;
845
846 XPinit(env, 64);
847 for (l = e->loc; l != NULL; l = l->next)
848 for (vpp = l->vars.tbls, i = l->vars.size; --i >= 0; )
849 if ((vp = *vpp++) != NULL
850 && (vp->flag&(ISSET|EXPORT)) == (ISSET|EXPORT)) {
851 register struct block *l2;
852 register struct tbl *vp2;
853 unsigned h = hash(vp->name);
854
855 /* unexport any redefined instances */
856 for (l2 = l->next; l2 != NULL; l2 = l2->next) {
857 vp2 = tsearch(&l2->vars, vp->name, h);
858 if (vp2 != NULL)
859 vp2->flag &= ~EXPORT;
860 }
861 if ((vp->flag&INTEGER)) {
862 /* integer to string */
863 char *val;
864 val = str_val(vp);
865 vp->flag &= ~(INTEGER|RDONLY);
866 /* setstr can't fail here */
867 setstr(vp, val, KSH_RETURN_ERROR);
868 }
869 XPput(env, vp->val.s);
870 }
871 XPput(env, NULL);
872 return (char **) XPclose(env);
873 }
874
875 /*
876 * Called after a fork in parent to bump the random number generator.
877 * Done to ensure children will not get the same random number sequence
878 * if the parent doesn't use $RANDOM.
879 */
880 void
change_random()881 change_random()
882 {
883 rand();
884 }
885
886 /*
887 * handle special variables with side effects - PATH, SECONDS.
888 */
889
890 /* Test if name is a special parameter */
891 static int
special(name)892 special(name)
893 register const char * name;
894 {
895 register struct tbl *tp;
896
897 tp = tsearch(&specials, name, hash(name));
898 return tp && (tp->flag & ISSET) ? tp->type : V_NONE;
899 }
900
901 /* Make a variable non-special */
902 static void
unspecial(name)903 unspecial(name)
904 register const char * name;
905 {
906 register struct tbl *tp;
907
908 tp = tsearch(&specials, name, hash(name));
909 if (tp)
910 tdelete(tp);
911 }
912
913 #ifdef KSH
914 static time_t seconds; /* time SECONDS last set */
915 #endif /* KSH */
916 static int user_lineno; /* what user set $LINENO to */
917
918 static void
getspec(vp)919 getspec(vp)
920 register struct tbl *vp;
921 {
922 switch (special(vp->name)) {
923 #ifdef KSH
924 case V_SECONDS:
925 vp->flag &= ~SPECIAL;
926 /* On start up the value of SECONDS is used before seconds
927 * has been set - don't do anything in this case
928 * (see initcoms[] in main.c).
929 */
930 if (vp->flag & ISSET)
931 setint(vp, (long) (time((time_t *)0) - seconds));
932 vp->flag |= SPECIAL;
933 break;
934 case V_RANDOM:
935 vp->flag &= ~SPECIAL;
936 setint(vp, (long) (rand() & 0x7fff));
937 vp->flag |= SPECIAL;
938 break;
939 #endif /* KSH */
940 #ifdef HISTORY
941 case V_HISTSIZE:
942 vp->flag &= ~SPECIAL;
943 setint(vp, (long) histsize);
944 vp->flag |= SPECIAL;
945 break;
946 #endif /* HISTORY */
947 case V_OPTIND:
948 vp->flag &= ~SPECIAL;
949 setint(vp, (long) user_opt.uoptind);
950 vp->flag |= SPECIAL;
951 break;
952 case V_LINENO:
953 vp->flag &= ~SPECIAL;
954 setint(vp, (long) current_lineno + user_lineno);
955 vp->flag |= SPECIAL;
956 break;
957 }
958 }
959
960 static void
setspec(vp)961 setspec(vp)
962 register struct tbl *vp;
963 {
964 char *s;
965
966 switch (special(vp->name)) {
967 case V_PATH:
968 if (path)
969 afree(path, APERM);
970 path = str_save(str_val(vp), APERM);
971 flushcom(1); /* clear tracked aliases */
972 break;
973 case V_IFS:
974 setctypes(s = str_val(vp), C_IFS);
975 ifs0 = *s;
976 break;
977 case V_OPTIND:
978 vp->flag &= ~SPECIAL;
979 getopts_reset((int) intval(vp));
980 vp->flag |= SPECIAL;
981 break;
982 case V_POSIXLY_CORRECT:
983 change_flag(FPOSIX, OF_SPECIAL, 1);
984 break;
985 case V_TMPDIR:
986 if (tmpdir) {
987 afree(tmpdir, APERM);
988 tmpdir = (char *) 0;
989 }
990 /* Use tmpdir iff it is an absolute path, is writable and
991 * searchable and is a directory...
992 */
993 {
994 struct stat statb;
995 s = str_val(vp);
996 if (ISABSPATH(s) && eaccess(s, W_OK|X_OK) == 0
997 && stat(s, &statb) == 0 && S_ISDIR(statb.st_mode))
998 tmpdir = str_save(s, APERM);
999 }
1000 break;
1001 #ifdef HISTORY
1002 case V_HISTSIZE:
1003 vp->flag &= ~SPECIAL;
1004 sethistsize((int) intval(vp));
1005 vp->flag |= SPECIAL;
1006 break;
1007 case V_HISTFILE:
1008 sethistfile(str_val(vp));
1009 break;
1010 #endif /* HISTORY */
1011 #ifdef EDIT
1012 case V_VISUAL:
1013 set_editmode(str_val(vp));
1014 break;
1015 case V_EDITOR:
1016 if (!(global("VISUAL")->flag & ISSET))
1017 set_editmode(str_val(vp));
1018 break;
1019 case V_COLUMNS:
1020 if ((x_cols = intval(vp)) <= MIN_COLS)
1021 x_cols = MIN_COLS;
1022 break;
1023 #endif /* EDIT */
1024 #ifdef KSH
1025 case V_MAIL:
1026 mbset(str_val(vp));
1027 break;
1028 case V_MAILPATH:
1029 mpset(str_val(vp));
1030 break;
1031 case V_MAILCHECK:
1032 vp->flag &= ~SPECIAL;
1033 mcset(intval(vp));
1034 vp->flag |= SPECIAL;
1035 break;
1036 case V_RANDOM:
1037 vp->flag &= ~SPECIAL;
1038 srand((unsigned int)intval(vp));
1039 vp->flag |= SPECIAL;
1040 break;
1041 case V_SECONDS:
1042 vp->flag &= ~SPECIAL;
1043 seconds = time((time_t*) 0) - intval(vp);
1044 vp->flag |= SPECIAL;
1045 break;
1046 case V_TMOUT:
1047 /* at&t ksh seems to do this (only listen if integer) */
1048 if (vp->flag & INTEGER)
1049 ksh_tmout = vp->val.i >= 0 ? vp->val.i : 0;
1050 break;
1051 #endif /* KSH */
1052 case V_LINENO:
1053 vp->flag &= ~SPECIAL;
1054 /* The -1 is because line numbering starts at 1. */
1055 user_lineno = (unsigned int) intval(vp) - current_lineno - 1;
1056 vp->flag |= SPECIAL;
1057 break;
1058 }
1059 }
1060
1061 static void
unsetspec(vp)1062 unsetspec(vp)
1063 register struct tbl *vp;
1064 {
1065 switch (special(vp->name)) {
1066 case V_PATH:
1067 if (path)
1068 afree(path, APERM);
1069 path = str_save(def_path, APERM);
1070 flushcom(1); /* clear tracked aliases */
1071 break;
1072 case V_IFS:
1073 setctypes(" \t\n", C_IFS);
1074 ifs0 = ' ';
1075 break;
1076 case V_TMPDIR:
1077 /* should not become unspecial */
1078 if (tmpdir) {
1079 afree(tmpdir, APERM);
1080 tmpdir = (char *) 0;
1081 }
1082 break;
1083 #ifdef KSH
1084 case V_MAIL:
1085 mbset((char *) 0);
1086 break;
1087 case V_MAILPATH:
1088 mpset((char *) 0);
1089 break;
1090 #endif /* KSH */
1091
1092 case V_LINENO:
1093 #ifdef KSH
1094 case V_MAILCHECK: /* at&t ksh leaves previous value in place */
1095 case V_RANDOM:
1096 case V_SECONDS:
1097 case V_TMOUT: /* at&t ksh leaves previous value in place */
1098 #endif /* KSH */
1099 unspecial(vp->name);
1100 break;
1101
1102 /* at&t ksh man page says OPTIND, OPTARG and _ lose special meaning,
1103 * but OPTARG does not (still set by getopts) and _ is also still
1104 * set in various places.
1105 * Don't know what at&t does for:
1106 * MAIL, MAILPATH, HISTSIZE, HISTFILE,
1107 * Unsetting these in at&t ksh does not loose the `specialness':
1108 * no effect: IFS, COLUMNS, PATH, TMPDIR,
1109 * VISUAL, EDITOR,
1110 * pdkshisms: no effect:
1111 * POSIXLY_CORRECT (use set +o posix instead)
1112 */
1113 }
1114 }
1115
1116 /*
1117 * Search for (and possibly create) a table entry starting with
1118 * vp, indexed by val.
1119 */
1120 static struct tbl *
arraysearch(vp,val)1121 arraysearch(vp, val)
1122 struct tbl *vp;
1123 int val;
1124 {
1125 struct tbl *prev, *curr, *new;
1126
1127 vp->flag |= ARRAY|DEFINED;
1128
1129 /* The table entry is always [0] */
1130 if (val == 0) {
1131 vp->index = 0;
1132 return vp;
1133 }
1134 prev = vp;
1135 curr = vp->u.array;
1136 while (curr && curr->index < val) {
1137 prev = curr;
1138 curr = curr->u.array;
1139 }
1140 if (curr && curr->index == val) {
1141 if (curr->flag&ISSET)
1142 return curr;
1143 else
1144 new = curr;
1145 } else
1146 new = (struct tbl *)alloc(sizeof(struct tbl)+strlen(vp->name)+1, vp->areap);
1147 strcpy(new->name, vp->name);
1148 new->flag = vp->flag & ~(ALLOC|DEFINED|ISSET|SPECIAL);
1149 new->type = vp->type;
1150 new->areap = vp->areap;
1151 new->u2.field = vp->u2.field;
1152 new->index = val;
1153 if (curr != new) { /* not reusing old array entry */
1154 prev->u.array = new;
1155 new->u.array = curr;
1156 }
1157 return new;
1158 }
1159
1160 /* Return the length of an array reference (eg, [1+2]) - cp is assumed
1161 * to point to the open bracket. Returns 0 if there is no matching closing
1162 * bracket.
1163 */
1164 int
array_ref_len(cp)1165 array_ref_len(cp)
1166 const char *cp;
1167 {
1168 const char *s = cp;
1169 int c;
1170 int depth = 0;
1171
1172 while ((c = *s++) && (c != ']' || --depth))
1173 if (c == '[')
1174 depth++;
1175 if (!c)
1176 return 0;
1177 return s - cp;
1178 }
1179
1180 /*
1181 * Make a copy of the base of an array name
1182 */
1183 char *
arrayname(str)1184 arrayname(str)
1185 const char *str;
1186 {
1187 const char *p;
1188
1189 if ((p = strchr(str, '[')) == 0)
1190 /* Shouldn't happen, but why worry? */
1191 return (char *) str;
1192
1193 return str_nsave(str, p - str, ATEMP);
1194 }
1195
1196 /* Set (or overwrite, if !reset) the array variable var to the values in vals.
1197 */
1198 void
set_array(var,reset,vals)1199 set_array(var, reset, vals)
1200 const char *var;
1201 int reset;
1202 char **vals;
1203 {
1204 struct tbl *vp, *vq;
1205 int i;
1206
1207 /* to get local array, use "typeset foo; set -A foo" */
1208 vp = global(var);
1209
1210 /* Note: at&t ksh allows set -A but not set +A of a read-only var */
1211 if ((vp->flag&RDONLY))
1212 errorf("%s: is read only", var);
1213 /* This code is quite non-optimal */
1214 if (reset > 0)
1215 /* trash existing values and attributes */
1216 unset(vp, 0);
1217 /* todo: would be nice for assignment to completely succeed or
1218 * completely fail. Only really effects integer arrays:
1219 * evaluation of some of vals[] may fail...
1220 */
1221 for (i = 0; vals[i]; i++) {
1222 vq = arraysearch(vp, i);
1223 /* would be nice to deal with errors here... (see above) */
1224 setstr(vq, vals[i], KSH_RETURN_ERROR);
1225 }
1226 }
1227