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(n,arrayp,valp)126 array_index_calc(n, arrayp, valp)
127 const char *n;
128 bool_t *arrayp;
129 int *valp;
130 {
131 const char *p;
132 int len;
133
134 *arrayp = FALSE;
135 p = skip_varname(n, FALSE);
136 if (p != n && *p == '[' && (len = array_ref_len(p))) {
137 char *sub, *tmp;
138 long rval;
139
140 /* Calculate the value of the subscript */
141 *arrayp = TRUE;
142 tmp = str_nsave(p+1, len-2, ATEMP);
143 sub = substitute(tmp, 0);
144 afree(tmp, ATEMP);
145 n = str_nsave(n, p - n, ATEMP);
146 evaluate(sub, &rval, KSH_UNWIND_ERROR);
147 if (rval < 0 || rval > ARRAYMAX)
148 errorf("%s: subscript out of range", n);
149 *valp = rval;
150 afree(sub, ATEMP);
151 }
152 return n;
153 }
154
155 /*
156 * Search for variable, if not found create globally.
157 */
158 struct tbl *
global(n)159 global(n)
160 register const char *n;
161 {
162 register struct block *l = e->loc;
163 register struct tbl *vp;
164 register int c;
165 unsigned h;
166 bool_t array;
167 int val;
168
169 /* Check to see if this is an array */
170 n = array_index_calc(n, &array, &val);
171 h = hash(n);
172 c = n[0];
173 if (!letter(c)) {
174 if (array)
175 errorf("bad substitution");
176 vp = &vtemp;
177 vp->flag = DEFINED;
178 vp->type = 0;
179 vp->areap = ATEMP;
180 *vp->name = c;
181 if (digit(c)) {
182 for (c = 0; digit(*n); n++)
183 c = c*10 + *n-'0';
184 if (c <= l->argc)
185 /* setstr can't fail here */
186 setstr(vp, l->argv[c], KSH_RETURN_ERROR);
187 vp->flag |= RDONLY;
188 return vp;
189 }
190 vp->flag |= RDONLY;
191 if (n[1] != '\0')
192 return vp;
193 vp->flag |= ISSET|INTEGER;
194 switch (c) {
195 case '$':
196 vp->val.i = kshpid;
197 break;
198 case '!':
199 /* If no job, expand to nothing */
200 if ((vp->val.i = j_async()) == 0)
201 vp->flag &= ~(ISSET|INTEGER);
202 break;
203 case '?':
204 vp->val.i = exstat;
205 break;
206 case '#':
207 vp->val.i = l->argc;
208 break;
209 case '-':
210 vp->flag &= ~INTEGER;
211 vp->val.s = getoptions();
212 break;
213 default:
214 vp->flag &= ~(ISSET|INTEGER);
215 }
216 return vp;
217 }
218 for (l = e->loc; ; l = l->next) {
219 vp = tsearch(&l->vars, n, h);
220 if (vp != NULL)
221 if (array)
222 return arraysearch(vp, val);
223 else
224 return vp;
225 if (l->next == NULL)
226 break;
227 }
228 vp = tenter(&l->vars, n, h);
229 if (array)
230 vp = arraysearch(vp, val);
231 vp->flag |= DEFINED;
232 if (special(n))
233 vp->flag |= SPECIAL;
234 return vp;
235 }
236
237 /*
238 * Search for local variable, if not found create locally.
239 */
240 struct tbl *
local(n,copy)241 local(n, copy)
242 register const char *n;
243 bool_t copy;
244 {
245 register struct block *l = e->loc;
246 register struct tbl *vp;
247 unsigned h;
248 bool_t array;
249 int val;
250
251 /* Check to see if this is an array */
252 n = array_index_calc(n, &array, &val);
253 h = hash(n);
254 if (!letter(*n)) {
255 vp = &vtemp;
256 vp->flag = DEFINED|RDONLY;
257 vp->type = 0;
258 vp->areap = ATEMP;
259 return vp;
260 }
261 vp = tenter(&l->vars, n, h);
262 if (copy && !(vp->flag & DEFINED)) {
263 struct block *ll = l;
264 struct tbl *vq = (struct tbl *) 0;
265
266 while ((ll = ll->next) && !(vq = tsearch(&ll->vars, n, h)))
267 ;
268 if (vq) {
269 vp->flag |= vq->flag & (EXPORT|INTEGER|RDONLY
270 |LJUST|RJUST|ZEROFIL
271 |LCASEV|UCASEV_AL|INT_U|INT_L);
272 if (vq->flag & INTEGER)
273 vp->type = vq->type;
274 vp->u2.field = vq->u2.field;
275 }
276 }
277 if (array)
278 vp = arraysearch(vp, val);
279 vp->flag |= DEFINED;
280 if (special(n))
281 vp->flag |= SPECIAL;
282 return vp;
283 }
284
285 /* get variable string value */
286 char *
str_val(vp)287 str_val(vp)
288 register struct tbl *vp;
289 {
290 char *s;
291
292 if ((vp->flag&SPECIAL))
293 getspec(vp);
294 if (!(vp->flag&ISSET))
295 s = null; /* special to dollar() */
296 else if (!(vp->flag&INTEGER)) /* string source */
297 s = vp->val.s + vp->type;
298 else { /* integer source */
299 /* worst case number length is when base=2, so use BITS(long) */
300 /* minus base # number null */
301 static char strbuf[1 + 2 + 1 + BITS(long) + 1];
302 const char *digits = (vp->flag & UCASEV_AL) ?
303 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
304 : "0123456789abcdefghijklmnopqrstuvwxyz";
305 register unsigned long n;
306 register int base;
307
308 s = strbuf + sizeof(strbuf);
309 if (vp->flag & INT_U)
310 n = (unsigned long) vp->val.i;
311 else
312 n = (vp->val.i < 0) ? -vp->val.i : vp->val.i;
313 base = (vp->type == 0) ? 10 : vp->type;
314
315 *--s = '\0';
316 do {
317 *--s = digits[n % base];
318 n /= base;
319 } while (n != 0);
320 if (base != 10) {
321 *--s = '#';
322 *--s = digits[base % 10];
323 if (base >= 10)
324 *--s = digits[base / 10];
325 }
326 if (!(vp->flag & INT_U) && vp->val.i < 0)
327 *--s = '-';
328 if (vp->flag & (RJUST|LJUST)) /* case already dealt with */
329 s = formatstr(vp, s);
330 }
331 return s;
332 }
333
334 /* get variable integer value, with error checking */
335 long
intval(vp)336 intval(vp)
337 register struct tbl *vp;
338 {
339 long num;
340 int base;
341
342 base = getint(vp, &num);
343 if (base == -1)
344 /* XXX check calls - is error here ok by POSIX? */
345 errorf("%s: bad number", str_val(vp));
346 return num;
347 }
348
349 /* set variable to string value */
350 int
setstr(vq,s,error_ok)351 setstr(vq, s, error_ok)
352 register struct tbl *vq;
353 const char *s;
354 int error_ok;
355 {
356 int no_ro_check = error_ok & 0x4;
357 error_ok &= ~0x4;
358 if ((vq->flag & RDONLY) && !no_ro_check) {
359 warningf(TRUE, "%s: is read only", vq->name);
360 if (!error_ok)
361 errorf(null);
362 return 0;
363 }
364 if (!(vq->flag&INTEGER)) { /* string dest */
365 if ((vq->flag&ALLOC)) {
366 /* debugging */
367 if (s >= vq->val.s
368 && s <= vq->val.s + strlen(vq->val.s))
369 internal_errorf(TRUE,
370 "setstr: %s=%s: assigning to self",
371 vq->name, s);
372 afree((void*)vq->val.s, vq->areap);
373 }
374 vq->flag &= ~(ISSET|ALLOC);
375 vq->type = 0;
376 if (s && (vq->flag & (UCASEV_AL|LCASEV|LJUST|RJUST)))
377 s = formatstr(vq, s);
378 if ((vq->flag&EXPORT))
379 export(vq, s);
380 else {
381 vq->val.s = str_save(s, vq->areap);
382 if (vq->val.s) /* <sjg> don't lie */
383 vq->flag |= ALLOC;
384 }
385 } else /* integer dest */
386 if (!v_evaluate(vq, s, error_ok))
387 return 0;
388 vq->flag |= ISSET;
389 if ((vq->flag&SPECIAL))
390 setspec(vq);
391 return 1;
392 }
393
394 /* set variable to integer */
395 void
setint(vq,n)396 setint(vq, n)
397 register struct tbl *vq;
398 long n;
399 {
400 if (!(vq->flag&INTEGER)) {
401 register struct tbl *vp = &vtemp;
402 vp->flag = (ISSET|INTEGER);
403 vp->type = 0;
404 vp->areap = ATEMP;
405 vp->val.i = n;
406 /* setstr can't fail here */
407 setstr(vq, str_val(vp), KSH_RETURN_ERROR);
408 } else
409 vq->val.i = n;
410 vq->flag |= ISSET;
411 if ((vq->flag&SPECIAL))
412 setspec(vq);
413 }
414
415 int
getint(vp,nump)416 getint(vp, nump)
417 struct tbl *vp;
418 long *nump;
419 {
420 register char *s;
421 register int c;
422 int base, neg;
423 int have_base = 0;
424 long num;
425
426 if (vp->flag&SPECIAL)
427 getspec(vp);
428 /* XXX is it possible for ISSET to be set and val.s to be 0? */
429 if (!(vp->flag&ISSET) || (!(vp->flag&INTEGER) && vp->val.s == NULL))
430 return -1;
431 if (vp->flag&INTEGER) {
432 *nump = vp->val.i;
433 return vp->type;
434 }
435 s = vp->val.s + vp->type;
436 if (s == NULL) /* redundent given initial test */
437 s = null;
438 base = 10;
439 num = 0;
440 neg = 0;
441 for (c = *s++; c ; c = *s++) {
442 if (c == '-') {
443 neg++;
444 } else if (c == '#') {
445 base = (int) num;
446 if (have_base || base < 2 || base > 36)
447 return -1;
448 num = 0;
449 have_base = 1;
450 } else if (letnum(c)) {
451 if (isdigit(c))
452 c -= '0';
453 else if (islower(c))
454 c -= 'a' - 10; /* todo: assumes ascii */
455 else if (isupper(c))
456 c -= 'A' - 10; /* todo: assumes ascii */
457 else
458 c = -1; /* _: force error */
459 if (c < 0 || c >= base)
460 return -1;
461 num = num * base + c;
462 } else
463 return -1;
464 }
465 if (neg)
466 num = -num;
467 *nump = num;
468 return base;
469 }
470
471 /* convert variable vq to integer variable, setting its value from vp
472 * (vq and vp may be the same)
473 */
474 struct tbl *
setint_v(vq,vp)475 setint_v(vq, vp)
476 register struct tbl *vq, *vp;
477 {
478 int base;
479 long num;
480
481 if ((base = getint(vp, &num)) == -1)
482 return NULL;
483 if (!(vq->flag & INTEGER) && (vq->flag & ALLOC)) {
484 vq->flag &= ~ALLOC;
485 afree(vq->val.s, vq->areap);
486 }
487 vq->val.i = num;
488 if (vq->type == 0) /* default base */
489 vq->type = base;
490 vq->flag |= ISSET|INTEGER;
491 if (vq->flag&SPECIAL)
492 setspec(vq);
493 return vq;
494 }
495
496 static char *
formatstr(vp,s)497 formatstr(vp, s)
498 struct tbl *vp;
499 const char *s;
500 {
501 int olen, nlen;
502 char *p, *q;
503
504 olen = strlen(s);
505
506 if (vp->flag & (RJUST|LJUST)) {
507 if (!vp->u2.field) /* default field width */
508 vp->u2.field = olen;
509 nlen = vp->u2.field;
510 } else
511 nlen = olen;
512
513 p = (char *) alloc(nlen + 1, ATEMP);
514 if (vp->flag & (RJUST|LJUST)) {
515 int slen;
516
517 if (vp->flag & RJUST) {
518 const char *q = s + olen;
519 /* strip trailing spaces (at&t ksh uses q[-1] == ' ') */
520 while (q > s && isspace(q[-1]))
521 --q;
522 slen = q - s;
523 if (slen > vp->u2.field) {
524 s += slen - vp->u2.field;
525 slen = vp->u2.field;
526 }
527 shf_snprintf(p, nlen + 1,
528 ((vp->flag & ZEROFIL) && digit(*s)) ?
529 "%0*s%.*s" : "%*s%.*s",
530 vp->u2.field - slen, null, slen, s);
531 } else {
532 /* strip leading spaces/zeros */
533 while (isspace(*s))
534 s++;
535 if (vp->flag & ZEROFIL)
536 while (*s == '0')
537 s++;
538 shf_snprintf(p, nlen + 1, "%-*.*s",
539 vp->u2.field, vp->u2.field, s);
540 }
541 } else
542 memcpy(p, s, olen + 1);
543
544 if (vp->flag & UCASEV_AL) {
545 for (q = p; *q; q++)
546 if (islower(*q))
547 *q = toupper(*q);
548 } else if (vp->flag & LCASEV) {
549 for (q = p; *q; q++)
550 if (isupper(*q))
551 *q = tolower(*q);
552 }
553
554 return p;
555 }
556
557 /*
558 * make vp->val.s be "name=value" for quick exporting.
559 */
560 static void
export(vp,val)561 export(vp, val)
562 register struct tbl *vp;
563 const char *val;
564 {
565 register char *xp;
566 char *op = (vp->flag&ALLOC) ? vp->val.s : NULL;
567 int namelen = strlen(vp->name);
568 int vallen = strlen(val) + 1;
569
570 vp->flag |= ALLOC;
571 xp = (char*)alloc(namelen + 1 + vallen, vp->areap);
572 memcpy(vp->val.s = xp, vp->name, namelen);
573 xp += namelen;
574 *xp++ = '=';
575 vp->type = xp - vp->val.s; /* offset to value */
576 memcpy(xp, val, vallen);
577 if (op != NULL)
578 afree((void*)op, vp->areap);
579 }
580
581 /*
582 * lookup variable (according to (set&LOCAL)),
583 * set its attributes (INTEGER, RDONLY, EXPORT, TRACE, LJUST, RJUST, ZEROFIL,
584 * LCASEV, UCASEV_AL), and optionally set its value if an assignment.
585 */
586 struct tbl *
typeset(var,set,clr,field,base)587 typeset(var, set, clr, field, base)
588 register const char *var;
589 Tflag clr, set;
590 int field, base;
591 {
592 register struct tbl *vp;
593 struct tbl *vpbase, *t;
594 char *tvar;
595 const char *val;
596
597 /* check for valid variable name, search for value */
598 val = skip_varname(var, FALSE);
599 if (val == var)
600 return NULL;
601 if (*val == '[') {
602 int len;
603
604 len = array_ref_len(val);
605 if (len == 0)
606 return NULL;
607 /* IMPORT is only used when the shell starts up and is
608 * setting up its environment. Allow only simple array
609 * references at this time since parameter/command substitution
610 * is preformed on the [expression], which would be a major
611 * security hole.
612 */
613 if (set & IMPORT) {
614 int i;
615 for (i = 1; i < len - 1; i++)
616 if (!digit(val[i]))
617 return NULL;
618 }
619 val += len;
620 }
621 if (*val == '=')
622 tvar = str_nsave(var, val++ - var, ATEMP);
623 else {
624 /* Importing from original envirnment: must have an = */
625 if (set & IMPORT)
626 return NULL;
627 tvar = (char *) var;
628 val = NULL;
629 }
630
631 /* Prevent typeset from creating a local PATH/ENV/SHELL */
632 if (Flag(FRESTRICTED) && (strcmp(tvar, "PATH") == 0
633 || strcmp(tvar, "ENV") == 0
634 || strcmp(tvar, "SHELL") == 0))
635 errorf("%s: restricted", tvar);
636
637 vp = (set&LOCAL) ? local(tvar, (set & LOCAL_COPY) ? TRUE : FALSE)
638 : global(tvar);
639 set &= ~(LOCAL|LOCAL_COPY);
640
641 vpbase = (vp->flag & ARRAY) ? global(arrayname(var)) : vp;
642
643 /* only allow export flag to be set. at&t ksh allows any attribute to
644 * be changed, which means it can be truncated or modified
645 * (-L/-R/-Z/-i).
646 */
647 if ((vpbase->flag&RDONLY)
648 && (val || clr || (set & ~EXPORT)))
649 /* XXX check calls - is error here ok by POSIX? */
650 errorf("%s: is read only", tvar);
651 if (val)
652 afree(tvar, ATEMP);
653
654 /* most calls are with set/clr == 0 */
655 if (set | clr) {
656 int ok = 1;
657 /* XXX if x[0] isn't set, there will be problems: need to have
658 * one copy of attributes for arrays...
659 */
660 for (t = vpbase; t; t = t->u.array) {
661 int fake_assign;
662 char UNINITIALIZED(*s);
663 char UNINITIALIZED(*free_me);
664
665 fake_assign = (t->flag & ISSET) && (!val || t != vp)
666 && ((set & (UCASEV_AL|LCASEV|LJUST|RJUST|ZEROFIL))
667 || ((t->flag & INTEGER) && (clr & INTEGER))
668 || (!(t->flag & INTEGER) && (set & INTEGER)));
669 if (fake_assign) {
670 if (t->flag & INTEGER) {
671 s = str_val(t);
672 free_me = (char *) 0;
673 } else {
674 s = t->val.s + t->type;
675 free_me = (t->flag & ALLOC) ? t->val.s
676 : (char *) 0;
677 }
678 t->flag &= ~ALLOC;
679 }
680 if (!(t->flag & INTEGER) && (set & INTEGER)) {
681 t->type = 0;
682 t->flag &= ~ALLOC;
683 }
684 t->flag = (t->flag | set) & ~clr;
685 /* Don't change base if assignment is to be done,
686 * in case assignment fails.
687 */
688 if ((set & INTEGER) && base > 0 && (!val || t != vp))
689 t->type = base;
690 if (set & (LJUST|RJUST|ZEROFIL))
691 t->u2.field = field;
692 if (fake_assign) {
693 if (!setstr(t, s, KSH_RETURN_ERROR)) {
694 /* Somewhat arbitrary action here:
695 * zap contents of varibale, but keep
696 * the flag settings.
697 */
698 ok = 0;
699 if (t->flag & INTEGER)
700 t->flag &= ~ISSET;
701 else {
702 if (t->flag & ALLOC)
703 afree((void*) t->val.s,
704 t->areap);
705 t->flag &= ~(ISSET|ALLOC);
706 t->type = 0;
707 }
708 }
709 if (free_me)
710 afree((void *) free_me, t->areap);
711 }
712 }
713 if (!ok)
714 errorf(null);
715 }
716
717 if (val != NULL) {
718 if (vp->flag&INTEGER) {
719 /* do not zero base before assignment */
720 setstr(vp, val, KSH_UNWIND_ERROR | 0x4);
721 /* Done after assignment to override default */
722 if (base > 0)
723 vp->type = base;
724 } else
725 /* setstr can't fail (readonly check already done) */
726 setstr(vp, val, KSH_RETURN_ERROR | 0x4);
727 }
728
729 /* only x[0] is ever exported, so use vpbase */
730 if ((vpbase->flag&EXPORT) && !(vpbase->flag&INTEGER)
731 && vpbase->type == 0)
732 export(vpbase, (vpbase->flag&ISSET) ? vpbase->val.s : null);
733
734 return vp;
735 }
736
737 /* Unset a variable. array_ref is set if there was an array reference in
738 * the name lookup (eg, x[2]).
739 */
740 void
unset(vp,array_ref)741 unset(vp, array_ref)
742 register struct tbl *vp;
743 int array_ref;
744 {
745 if (vp->flag & ALLOC)
746 afree((void*)vp->val.s, vp->areap);
747 if ((vp->flag & ARRAY) && !array_ref) {
748 struct tbl *a, *tmp;
749
750 /* Free up entire array */
751 for (a = vp->u.array; a; ) {
752 tmp = a;
753 a = a->u.array;
754 if (tmp->flag & ALLOC)
755 afree((void *) tmp->val.s, tmp->areap);
756 afree(tmp, tmp->areap);
757 }
758 vp->u.array = (struct tbl *) 0;
759 }
760 /* If foo[0] is being unset, the remainder of the array is kept... */
761 vp->flag &= SPECIAL | (array_ref ? ARRAY|DEFINED : 0);
762 if (vp->flag & SPECIAL)
763 unsetspec(vp); /* responsible for `unspecial'ing var */
764 }
765
766 /* return a pointer to the first char past a legal variable name (returns the
767 * argument if there is no legal name, returns * a pointer to the terminating
768 * null if whole string is legal).
769 */
770 char *
skip_varname(s,aok)771 skip_varname(s, aok)
772 const char *s;
773 int aok;
774 {
775 int alen;
776
777 if (s && letter(*s)) {
778 while (*++s && letnum(*s))
779 ;
780 if (aok && *s == '[' && (alen = array_ref_len(s)))
781 s += alen;
782 }
783 return (char *) s;
784 }
785
786 /* Return a pointer to the first character past any legal variable name. */
787 char *
skip_wdvarname(s,aok)788 skip_wdvarname(s, aok)
789 const char *s;
790 int aok; /* skip array de-reference? */
791 {
792 if (s[0] == CHAR && letter(s[1])) {
793 do
794 s += 2;
795 while (s[0] == CHAR && letnum(s[1]));
796 if (aok && s[0] == CHAR && s[1] == '[') {
797 /* skip possible array de-reference */
798 const char *p = s;
799 char c;
800 int depth = 0;
801
802 while (1) {
803 if (p[0] != CHAR)
804 break;
805 c = p[1];
806 p += 2;
807 if (c == '[')
808 depth++;
809 else if (c == ']' && --depth == 0) {
810 s = p;
811 break;
812 }
813 }
814 }
815 }
816 return (char *) s;
817 }
818
819 /* Check if coded string s is a variable name */
820 int
is_wdvarname(s,aok)821 is_wdvarname(s, aok)
822 const char *s;
823 int aok;
824 {
825 char *p = skip_wdvarname(s, aok);
826
827 return p != s && p[0] == EOS;
828 }
829
830 /* Check if coded string s is a variable assignment */
831 int
is_wdvarassign(s)832 is_wdvarassign(s)
833 const char *s;
834 {
835 char *p = skip_wdvarname(s, TRUE);
836
837 return p != s && p[0] == CHAR && p[1] == '=';
838 }
839
840 /*
841 * Make the exported environment from the exported names in the dictionary.
842 */
843 char **
makenv()844 makenv()
845 {
846 struct block *l = e->loc;
847 XPtrV env;
848 register struct tbl *vp, **vpp;
849 register int i;
850
851 XPinit(env, 64);
852 for (l = e->loc; l != NULL; l = l->next)
853 for (vpp = l->vars.tbls, i = l->vars.size; --i >= 0; )
854 if ((vp = *vpp++) != NULL
855 && (vp->flag&(ISSET|EXPORT)) == (ISSET|EXPORT)) {
856 register struct block *l2;
857 register struct tbl *vp2;
858 unsigned h = hash(vp->name);
859
860 /* unexport any redefined instances */
861 for (l2 = l->next; l2 != NULL; l2 = l2->next) {
862 vp2 = tsearch(&l2->vars, vp->name, h);
863 if (vp2 != NULL)
864 vp2->flag &= ~EXPORT;
865 }
866 if ((vp->flag&INTEGER)) {
867 /* integer to string */
868 char *val;
869 val = str_val(vp);
870 vp->flag &= ~(INTEGER|RDONLY);
871 /* setstr can't fail here */
872 setstr(vp, val, KSH_RETURN_ERROR);
873 }
874 XPput(env, vp->val.s);
875 }
876 XPput(env, NULL);
877 return (char **) XPclose(env);
878 }
879
880 /*
881 * Called after a fork in parent to bump the random number generator.
882 * Done to ensure children will not get the same random number sequence
883 * if the parent doesn't use $RANDOM.
884 */
885 void
change_random()886 change_random()
887 {
888 rand();
889 }
890
891 /*
892 * handle special variables with side effects - PATH, SECONDS.
893 */
894
895 /* Test if name is a special parameter */
896 static int
special(name)897 special(name)
898 register const char * name;
899 {
900 register struct tbl *tp;
901
902 tp = tsearch(&specials, name, hash(name));
903 return tp && (tp->flag & ISSET) ? tp->type : V_NONE;
904 }
905
906 /* Make a variable non-special */
907 static void
unspecial(name)908 unspecial(name)
909 register const char * name;
910 {
911 register struct tbl *tp;
912
913 tp = tsearch(&specials, name, hash(name));
914 if (tp)
915 tdelete(tp);
916 }
917
918 #ifdef KSH
919 static time_t seconds; /* time SECONDS last set */
920 #endif /* KSH */
921 static int user_lineno; /* what user set $LINENO to */
922
923 static void
getspec(vp)924 getspec(vp)
925 register struct tbl *vp;
926 {
927 switch (special(vp->name)) {
928 #ifdef KSH
929 case V_SECONDS:
930 vp->flag &= ~SPECIAL;
931 /* On start up the value of SECONDS is used before seconds
932 * has been set - don't do anything in this case
933 * (see initcoms[] in main.c).
934 */
935 if (vp->flag & ISSET)
936 setint(vp, (long) (time((time_t *)0) - seconds));
937 vp->flag |= SPECIAL;
938 break;
939 case V_RANDOM:
940 vp->flag &= ~SPECIAL;
941 setint(vp, (long) (rand() & 0x7fff));
942 vp->flag |= SPECIAL;
943 break;
944 #endif /* KSH */
945 #ifdef HISTORY
946 case V_HISTSIZE:
947 vp->flag &= ~SPECIAL;
948 setint(vp, (long) histsize);
949 vp->flag |= SPECIAL;
950 break;
951 #endif /* HISTORY */
952 case V_OPTIND:
953 vp->flag &= ~SPECIAL;
954 setint(vp, (long) user_opt.uoptind);
955 vp->flag |= SPECIAL;
956 break;
957 case V_LINENO:
958 vp->flag &= ~SPECIAL;
959 setint(vp, (long) current_lineno + user_lineno);
960 vp->flag |= SPECIAL;
961 break;
962 }
963 }
964
965 static void
setspec(vp)966 setspec(vp)
967 register struct tbl *vp;
968 {
969 char *s;
970
971 switch (special(vp->name)) {
972 case V_PATH:
973 if (path)
974 afree(path, APERM);
975 path = str_save(str_val(vp), APERM);
976 flushcom(1); /* clear tracked aliases */
977 break;
978 case V_IFS:
979 setctypes(s = str_val(vp), C_IFS);
980 ifs0 = *s;
981 break;
982 case V_OPTIND:
983 vp->flag &= ~SPECIAL;
984 getopts_reset((int) intval(vp));
985 vp->flag |= SPECIAL;
986 break;
987 case V_POSIXLY_CORRECT:
988 change_flag(FPOSIX, OF_SPECIAL, 1);
989 break;
990 case V_TMPDIR:
991 if (tmpdir) {
992 afree(tmpdir, APERM);
993 tmpdir = (char *) 0;
994 }
995 /* Use tmpdir iff it is an absolute path, is writable and
996 * searchable and is a directory...
997 */
998 {
999 struct stat statb;
1000 s = str_val(vp);
1001 if (ISABSPATH(s) && eaccess(s, W_OK|X_OK) == 0
1002 && stat(s, &statb) == 0 && S_ISDIR(statb.st_mode))
1003 tmpdir = str_save(s, APERM);
1004 }
1005 break;
1006 #ifdef HISTORY
1007 case V_HISTSIZE:
1008 vp->flag &= ~SPECIAL;
1009 sethistsize((int) intval(vp));
1010 vp->flag |= SPECIAL;
1011 break;
1012 case V_HISTFILE:
1013 sethistfile(str_val(vp));
1014 break;
1015 #endif /* HISTORY */
1016 #ifdef EDIT
1017 case V_VISUAL:
1018 set_editmode(str_val(vp));
1019 break;
1020 case V_EDITOR:
1021 if (!(global("VISUAL")->flag & ISSET))
1022 set_editmode(str_val(vp));
1023 break;
1024 case V_COLUMNS:
1025 if ((x_cols = intval(vp)) <= MIN_COLS)
1026 x_cols = MIN_COLS;
1027 break;
1028 #endif /* EDIT */
1029 #ifdef KSH
1030 case V_MAIL:
1031 mbset(str_val(vp));
1032 break;
1033 case V_MAILPATH:
1034 mpset(str_val(vp));
1035 break;
1036 case V_MAILCHECK:
1037 vp->flag &= ~SPECIAL;
1038 mcset(intval(vp));
1039 vp->flag |= SPECIAL;
1040 break;
1041 case V_RANDOM:
1042 vp->flag &= ~SPECIAL;
1043 srand((unsigned int)intval(vp));
1044 vp->flag |= SPECIAL;
1045 break;
1046 case V_SECONDS:
1047 vp->flag &= ~SPECIAL;
1048 seconds = time((time_t*) 0) - intval(vp);
1049 vp->flag |= SPECIAL;
1050 break;
1051 case V_TMOUT:
1052 /* at&t ksh seems to do this (only listen if integer) */
1053 if (vp->flag & INTEGER)
1054 ksh_tmout = vp->val.i >= 0 ? vp->val.i : 0;
1055 break;
1056 #endif /* KSH */
1057 case V_LINENO:
1058 vp->flag &= ~SPECIAL;
1059 /* The -1 is because line numbering starts at 1. */
1060 user_lineno = (unsigned int) intval(vp) - current_lineno - 1;
1061 vp->flag |= SPECIAL;
1062 break;
1063 }
1064 }
1065
1066 static void
unsetspec(vp)1067 unsetspec(vp)
1068 register struct tbl *vp;
1069 {
1070 switch (special(vp->name)) {
1071 case V_PATH:
1072 if (path)
1073 afree(path, APERM);
1074 path = str_save(def_path, APERM);
1075 flushcom(1); /* clear tracked aliases */
1076 break;
1077 case V_IFS:
1078 setctypes(" \t\n", C_IFS);
1079 ifs0 = ' ';
1080 break;
1081 case V_TMPDIR:
1082 /* should not become unspecial */
1083 if (tmpdir) {
1084 afree(tmpdir, APERM);
1085 tmpdir = (char *) 0;
1086 }
1087 break;
1088 #ifdef KSH
1089 case V_MAIL:
1090 mbset((char *) 0);
1091 break;
1092 case V_MAILPATH:
1093 mpset((char *) 0);
1094 break;
1095 #endif /* KSH */
1096
1097 case V_LINENO:
1098 #ifdef KSH
1099 case V_MAILCHECK: /* at&t ksh leaves previous value in place */
1100 case V_RANDOM:
1101 case V_SECONDS:
1102 case V_TMOUT: /* at&t ksh leaves previous value in place */
1103 #endif /* KSH */
1104 unspecial(vp->name);
1105 break;
1106
1107 /* at&t ksh man page says OPTIND, OPTARG and _ lose special meaning,
1108 * but OPTARG does not (still set by getopts) and _ is also still
1109 * set in various places.
1110 * Don't know what at&t does for:
1111 * MAIL, MAILPATH, HISTSIZE, HISTFILE,
1112 * Unsetting these in at&t ksh does not loose the `specialness':
1113 * no effect: IFS, COLUMNS, PATH, TMPDIR,
1114 * VISUAL, EDITOR,
1115 * pdkshisms: no effect:
1116 * POSIXLY_CORRECT (use set +o posix instead)
1117 */
1118 }
1119 }
1120
1121 /*
1122 * Search for (and possibly create) a table entry starting with
1123 * vp, indexed by val.
1124 */
1125 static struct tbl *
arraysearch(vp,val)1126 arraysearch(vp, val)
1127 struct tbl *vp;
1128 int val;
1129 {
1130 struct tbl *prev, *curr, *new;
1131
1132 vp->flag |= ARRAY|DEFINED;
1133
1134 /* The table entry is always [0] */
1135 if (val == 0) {
1136 vp->index = 0;
1137 return vp;
1138 }
1139 prev = vp;
1140 curr = vp->u.array;
1141 while (curr && curr->index < val) {
1142 prev = curr;
1143 curr = curr->u.array;
1144 }
1145 if (curr && curr->index == val) {
1146 if (curr->flag&ISSET)
1147 return curr;
1148 else
1149 new = curr;
1150 } else
1151 new = (struct tbl *)alloc(sizeof(struct tbl)+strlen(vp->name)+1, vp->areap);
1152 strcpy(new->name, vp->name);
1153 new->flag = vp->flag & ~(ALLOC|DEFINED|ISSET|SPECIAL);
1154 new->type = vp->type;
1155 new->areap = vp->areap;
1156 new->u2.field = vp->u2.field;
1157 new->index = val;
1158 if (curr != new) { /* not reusing old array entry */
1159 prev->u.array = new;
1160 new->u.array = curr;
1161 }
1162 return new;
1163 }
1164
1165 /* Return the length of an array reference (eg, [1+2]) - cp is assumed
1166 * to point to the open bracket. Returns 0 if there is no matching closing
1167 * bracket.
1168 */
1169 int
array_ref_len(cp)1170 array_ref_len(cp)
1171 const char *cp;
1172 {
1173 const char *s = cp;
1174 int c;
1175 int depth = 0;
1176
1177 while ((c = *s++) && (c != ']' || --depth))
1178 if (c == '[')
1179 depth++;
1180 if (!c)
1181 return 0;
1182 return s - cp;
1183 }
1184
1185 /*
1186 * Make a copy of the base of an array name
1187 */
1188 char *
arrayname(str)1189 arrayname(str)
1190 const char *str;
1191 {
1192 const char *p;
1193
1194 if ((p = strchr(str, '[')) == 0)
1195 /* Shouldn't happen, but why worry? */
1196 return (char *) str;
1197
1198 return str_nsave(str, p - str, ATEMP);
1199 }
1200
1201 /* Set (or overwrite, if !reset) the array variable var to the values in vals.
1202 */
1203 void
set_array(var,reset,vals)1204 set_array(var, reset, vals)
1205 const char *var;
1206 int reset;
1207 char **vals;
1208 {
1209 struct tbl *vp, *vq;
1210 int i;
1211
1212 /* to get local array, use "typeset foo; set -A foo" */
1213 vp = global(var);
1214
1215 /* Note: at&t ksh allows set -A but not set +A of a read-only var */
1216 if ((vp->flag&RDONLY))
1217 errorf("%s: is read only", var);
1218 /* This code is quite non-optimal */
1219 if (reset > 0)
1220 /* trash existing values and attributes */
1221 unset(vp, 0);
1222 /* todo: would be nice for assignment to completely succeed or
1223 * completely fail. Only really effects integer arrays:
1224 * evaluation of some of vals[] may fail...
1225 */
1226 for (i = 0; vals[i]; i++) {
1227 vq = arraysearch(vp, i);
1228 /* would be nice to deal with errors here... (see above) */
1229 setstr(vq, vals[i], KSH_RETURN_ERROR);
1230 }
1231 }
1232