1 /*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
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 * 4. 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 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
36 #endif
37 #endif /* not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD: stable/9/bin/sh/var.c 264644 2014-04-18 12:42:50Z jilles $");
40
41 #include <unistd.h>
42 #include <stdlib.h>
43 #include <paths.h>
44
45 /*
46 * Shell variables.
47 */
48
49 #include <locale.h>
50 #include <langinfo.h>
51
52 #include "shell.h"
53 #include "output.h"
54 #include "expand.h"
55 #include "nodes.h" /* for other headers */
56 #include "eval.h" /* defines cmdenviron */
57 #include "exec.h"
58 #include "syntax.h"
59 #include "options.h"
60 #include "mail.h"
61 #include "var.h"
62 #include "memalloc.h"
63 #include "error.h"
64 #include "mystring.h"
65 #include "parser.h"
66 #include "builtins.h"
67 #ifndef NO_HISTORY
68 #include "myhistedit.h"
69 #endif
70
71
72 #define VTABSIZE 39
73
74
75 struct varinit {
76 struct var *var;
77 int flags;
78 const char *text;
79 void (*func)(const char *);
80 };
81
82
83 #ifndef NO_HISTORY
84 struct var vhistsize;
85 struct var vterm;
86 #endif
87 struct var vifs;
88 struct var vmail;
89 struct var vmpath;
90 struct var vpath;
91 struct var vppid;
92 struct var vps1;
93 struct var vps2;
94 struct var vps4;
95 struct var vvers;
96 static struct var voptind;
97 struct var vdisvfork;
98
99 int forcelocal;
100
101 static const struct varinit varinit[] = {
102 #ifndef NO_HISTORY
103 { &vhistsize, VUNSET, "HISTSIZE=",
104 sethistsize },
105 #endif
106 { &vifs, 0, "IFS= \t\n",
107 NULL },
108 { &vmail, VUNSET, "MAIL=",
109 NULL },
110 { &vmpath, VUNSET, "MAILPATH=",
111 NULL },
112 { &vpath, 0, "PATH=" _PATH_DEFPATH,
113 changepath },
114 { &vppid, VUNSET, "PPID=",
115 NULL },
116 /*
117 * vps1 depends on uid
118 */
119 { &vps2, 0, "PS2=> ",
120 NULL },
121 { &vps4, 0, "PS4=+ ",
122 NULL },
123 #ifndef NO_HISTORY
124 { &vterm, VUNSET, "TERM=",
125 setterm },
126 #endif
127 { &voptind, 0, "OPTIND=1",
128 getoptsreset },
129 { &vdisvfork, VUNSET, "SH_DISABLE_VFORK=",
130 NULL },
131 { NULL, 0, NULL,
132 NULL }
133 };
134
135 static struct var *vartab[VTABSIZE];
136
137 static const char *const locale_names[7] = {
138 "LC_COLLATE", "LC_CTYPE", "LC_MONETARY",
139 "LC_NUMERIC", "LC_TIME", "LC_MESSAGES", NULL
140 };
141 static const int locale_categories[7] = {
142 LC_COLLATE, LC_CTYPE, LC_MONETARY, LC_NUMERIC, LC_TIME, LC_MESSAGES, 0
143 };
144
145 static int varequal(const char *, const char *);
146 static struct var *find_var(const char *, struct var ***, int *);
147 static int localevar(const char *);
148
149 /*
150 * Initialize the variable symbol tables and import the environment.
151 */
152
153 #ifdef mkinit
154 INCLUDE "var.h"
155 MKINIT char **environ;
156 INIT {
157 char **envp;
158
159 initvar();
160 for (envp = environ ; *envp ; envp++) {
161 if (strchr(*envp, '=')) {
162 setvareq(*envp, VEXPORT|VTEXTFIXED);
163 }
164 }
165 }
166 #endif
167
168
169 /*
170 * This routine initializes the builtin variables. It is called when the
171 * shell is initialized.
172 */
173
174 void
initvar(void)175 initvar(void)
176 {
177 char ppid[20];
178 const struct varinit *ip;
179 struct var *vp;
180 struct var **vpp;
181
182 for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
183 if (find_var(ip->text, &vpp, &vp->name_len) != NULL)
184 continue;
185 vp->next = *vpp;
186 *vpp = vp;
187 vp->text = __DECONST(char *, ip->text);
188 vp->flags = ip->flags | VSTRFIXED | VTEXTFIXED;
189 vp->func = ip->func;
190 }
191 /*
192 * PS1 depends on uid
193 */
194 if (find_var("PS1", &vpp, &vps1.name_len) == NULL) {
195 vps1.next = *vpp;
196 *vpp = &vps1;
197 vps1.text = __DECONST(char *, geteuid() ? "PS1=$ " : "PS1=# ");
198 vps1.flags = VSTRFIXED|VTEXTFIXED;
199 }
200 if ((vppid.flags & VEXPORT) == 0) {
201 fmtstr(ppid, sizeof(ppid), "%d", (int)getppid());
202 setvarsafe("PPID", ppid, 0);
203 }
204 }
205
206 /*
207 * Safe version of setvar, returns 1 on success 0 on failure.
208 */
209
210 int
setvarsafe(const char * name,const char * val,int flags)211 setvarsafe(const char *name, const char *val, int flags)
212 {
213 struct jmploc jmploc;
214 struct jmploc *const savehandler = handler;
215 int err = 0;
216 int inton;
217
218 inton = is_int_on();
219 if (setjmp(jmploc.loc))
220 err = 1;
221 else {
222 handler = &jmploc;
223 setvar(name, val, flags);
224 }
225 handler = savehandler;
226 SETINTON(inton);
227 return err;
228 }
229
230 /*
231 * Set the value of a variable. The flags argument is stored with the
232 * flags of the variable. If val is NULL, the variable is unset.
233 */
234
235 void
setvar(const char * name,const char * val,int flags)236 setvar(const char *name, const char *val, int flags)
237 {
238 const char *p;
239 int len;
240 int namelen;
241 char *nameeq;
242 int isbad;
243
244 isbad = 0;
245 p = name;
246 if (! is_name(*p))
247 isbad = 1;
248 p++;
249 for (;;) {
250 if (! is_in_name(*p)) {
251 if (*p == '\0' || *p == '=')
252 break;
253 isbad = 1;
254 }
255 p++;
256 }
257 namelen = p - name;
258 if (isbad)
259 error("%.*s: bad variable name", namelen, name);
260 len = namelen + 2; /* 2 is space for '=' and '\0' */
261 if (val == NULL) {
262 flags |= VUNSET;
263 } else {
264 len += strlen(val);
265 }
266 INTOFF;
267 nameeq = ckmalloc(len);
268 memcpy(nameeq, name, namelen);
269 nameeq[namelen] = '=';
270 if (val)
271 scopy(val, nameeq + namelen + 1);
272 else
273 nameeq[namelen + 1] = '\0';
274 setvareq(nameeq, flags);
275 INTON;
276 }
277
278 static int
localevar(const char * s)279 localevar(const char *s)
280 {
281 const char *const *ss;
282
283 if (*s != 'L')
284 return 0;
285 if (varequal(s + 1, "ANG"))
286 return 1;
287 if (strncmp(s + 1, "C_", 2) != 0)
288 return 0;
289 if (varequal(s + 3, "ALL"))
290 return 1;
291 for (ss = locale_names; *ss ; ss++)
292 if (varequal(s + 3, *ss + 3))
293 return 1;
294 return 0;
295 }
296
297
298 /*
299 * Sets/unsets an environment variable from a pointer that may actually be a
300 * pointer into environ where the string should not be manipulated.
301 */
302 static void
change_env(const char * s,int set)303 change_env(const char *s, int set)
304 {
305 char *eqp;
306 char *ss;
307
308 INTOFF;
309 ss = savestr(s);
310 if ((eqp = strchr(ss, '=')) != NULL)
311 *eqp = '\0';
312 if (set && eqp != NULL)
313 (void) setenv(ss, eqp + 1, 1);
314 else
315 (void) unsetenv(ss);
316 ckfree(ss);
317 INTON;
318
319 return;
320 }
321
322
323 /*
324 * Same as setvar except that the variable and value are passed in
325 * the first argument as name=value. Since the first argument will
326 * be actually stored in the table, it should not be a string that
327 * will go away.
328 */
329
330 void
setvareq(char * s,int flags)331 setvareq(char *s, int flags)
332 {
333 struct var *vp, **vpp;
334 int nlen;
335
336 if (aflag)
337 flags |= VEXPORT;
338 if (forcelocal && !(flags & (VNOSET | VNOLOCAL)))
339 mklocal(s);
340 vp = find_var(s, &vpp, &nlen);
341 if (vp != NULL) {
342 if (vp->flags & VREADONLY) {
343 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
344 ckfree(s);
345 error("%.*s: is read only", vp->name_len, s);
346 }
347 if (flags & VNOSET) {
348 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
349 ckfree(s);
350 return;
351 }
352 INTOFF;
353
354 if (vp->func && (flags & VNOFUNC) == 0)
355 (*vp->func)(s + vp->name_len + 1);
356
357 if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
358 ckfree(vp->text);
359
360 vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
361 vp->flags |= flags;
362 vp->text = s;
363
364 /*
365 * We could roll this to a function, to handle it as
366 * a regular variable function callback, but why bother?
367 *
368 * Note: this assumes iflag is not set to 1 initially.
369 * As part of init(), this is called before arguments
370 * are looked at.
371 */
372 if ((vp == &vmpath || (vp == &vmail && ! mpathset())) &&
373 iflag == 1)
374 chkmail(1);
375 if ((vp->flags & VEXPORT) && localevar(s)) {
376 change_env(s, 1);
377 (void) setlocale(LC_ALL, "");
378 updatecharset();
379 }
380 INTON;
381 return;
382 }
383 /* not found */
384 if (flags & VNOSET) {
385 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
386 ckfree(s);
387 return;
388 }
389 INTOFF;
390 vp = ckmalloc(sizeof (*vp));
391 vp->flags = flags;
392 vp->text = s;
393 vp->name_len = nlen;
394 vp->next = *vpp;
395 vp->func = NULL;
396 *vpp = vp;
397 if ((vp->flags & VEXPORT) && localevar(s)) {
398 change_env(s, 1);
399 (void) setlocale(LC_ALL, "");
400 updatecharset();
401 }
402 INTON;
403 }
404
405
406
407 /*
408 * Process a linked list of variable assignments.
409 */
410
411 void
listsetvar(struct strlist * list,int flags)412 listsetvar(struct strlist *list, int flags)
413 {
414 struct strlist *lp;
415
416 INTOFF;
417 for (lp = list ; lp ; lp = lp->next) {
418 setvareq(savestr(lp->text), flags);
419 }
420 INTON;
421 }
422
423
424
425 /*
426 * Find the value of a variable. Returns NULL if not set.
427 */
428
429 char *
lookupvar(const char * name)430 lookupvar(const char *name)
431 {
432 struct var *v;
433
434 v = find_var(name, NULL, NULL);
435 if (v == NULL || v->flags & VUNSET)
436 return NULL;
437 return v->text + v->name_len + 1;
438 }
439
440
441
442 /*
443 * Search the environment of a builtin command. If the second argument
444 * is nonzero, return the value of a variable even if it hasn't been
445 * exported.
446 */
447
448 char *
bltinlookup(const char * name,int doall)449 bltinlookup(const char *name, int doall)
450 {
451 struct strlist *sp;
452 struct var *v;
453 char *result;
454
455 result = NULL;
456 for (sp = cmdenviron ; sp ; sp = sp->next) {
457 if (varequal(sp->text, name))
458 result = strchr(sp->text, '=') + 1;
459 }
460 if (result != NULL)
461 return result;
462
463 v = find_var(name, NULL, NULL);
464 if (v == NULL || v->flags & VUNSET ||
465 (!doall && (v->flags & VEXPORT) == 0))
466 return NULL;
467 return v->text + v->name_len + 1;
468 }
469
470
471 /*
472 * Set up locale for a builtin (LANG/LC_* assignments).
473 */
474 void
bltinsetlocale(void)475 bltinsetlocale(void)
476 {
477 struct strlist *lp;
478 int act = 0;
479 char *loc, *locdef;
480 int i;
481
482 for (lp = cmdenviron ; lp ; lp = lp->next) {
483 if (localevar(lp->text)) {
484 act = 1;
485 break;
486 }
487 }
488 if (!act)
489 return;
490 loc = bltinlookup("LC_ALL", 0);
491 INTOFF;
492 if (loc != NULL) {
493 setlocale(LC_ALL, loc);
494 INTON;
495 updatecharset();
496 return;
497 }
498 locdef = bltinlookup("LANG", 0);
499 for (i = 0; locale_names[i] != NULL; i++) {
500 loc = bltinlookup(locale_names[i], 0);
501 if (loc == NULL)
502 loc = locdef;
503 if (loc != NULL)
504 setlocale(locale_categories[i], loc);
505 }
506 INTON;
507 updatecharset();
508 }
509
510 /*
511 * Undo the effect of bltinlocaleset().
512 */
513 void
bltinunsetlocale(void)514 bltinunsetlocale(void)
515 {
516 struct strlist *lp;
517
518 INTOFF;
519 for (lp = cmdenviron ; lp ; lp = lp->next) {
520 if (localevar(lp->text)) {
521 setlocale(LC_ALL, "");
522 updatecharset();
523 return;
524 }
525 }
526 INTON;
527 }
528
529 /*
530 * Update the localeisutf8 flag.
531 */
532 void
updatecharset(void)533 updatecharset(void)
534 {
535 char *charset;
536
537 charset = nl_langinfo(CODESET);
538 localeisutf8 = !strcmp(charset, "UTF-8");
539 }
540
541 void
initcharset(void)542 initcharset(void)
543 {
544 updatecharset();
545 initial_localeisutf8 = localeisutf8;
546 }
547
548 /*
549 * Generate a list of exported variables. This routine is used to construct
550 * the third argument to execve when executing a program.
551 */
552
553 char **
environment(void)554 environment(void)
555 {
556 int nenv;
557 struct var **vpp;
558 struct var *vp;
559 char **env, **ep;
560
561 nenv = 0;
562 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
563 for (vp = *vpp ; vp ; vp = vp->next)
564 if (vp->flags & VEXPORT)
565 nenv++;
566 }
567 ep = env = stalloc((nenv + 1) * sizeof *env);
568 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
569 for (vp = *vpp ; vp ; vp = vp->next)
570 if (vp->flags & VEXPORT)
571 *ep++ = vp->text;
572 }
573 *ep = NULL;
574 return env;
575 }
576
577
578 static int
var_compare(const void * a,const void * b)579 var_compare(const void *a, const void *b)
580 {
581 const char *const *sa, *const *sb;
582
583 sa = a;
584 sb = b;
585 /*
586 * This compares two var=value strings which creates a different
587 * order from what you would probably expect. POSIX is somewhat
588 * ambiguous on what should be sorted exactly.
589 */
590 return strcoll(*sa, *sb);
591 }
592
593
594 /*
595 * Command to list all variables which are set. This is invoked from the
596 * set command when it is called without any options or operands.
597 */
598
599 int
showvarscmd(int argc __unused,char ** argv __unused)600 showvarscmd(int argc __unused, char **argv __unused)
601 {
602 struct var **vpp;
603 struct var *vp;
604 const char *s;
605 const char **vars;
606 int i, n;
607
608 /*
609 * POSIX requires us to sort the variables.
610 */
611 n = 0;
612 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
613 for (vp = *vpp; vp; vp = vp->next) {
614 if (!(vp->flags & VUNSET))
615 n++;
616 }
617 }
618
619 INTOFF;
620 vars = ckmalloc(n * sizeof(*vars));
621 i = 0;
622 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
623 for (vp = *vpp; vp; vp = vp->next) {
624 if (!(vp->flags & VUNSET))
625 vars[i++] = vp->text;
626 }
627 }
628
629 qsort(vars, n, sizeof(*vars), var_compare);
630 for (i = 0; i < n; i++) {
631 /*
632 * Skip improper variable names so the output remains usable as
633 * shell input.
634 */
635 if (!isassignment(vars[i]))
636 continue;
637 s = strchr(vars[i], '=');
638 s++;
639 outbin(vars[i], s - vars[i], out1);
640 out1qstr(s);
641 out1c('\n');
642 }
643 ckfree(vars);
644 INTON;
645
646 return 0;
647 }
648
649
650
651 /*
652 * The export and readonly commands.
653 */
654
655 int
exportcmd(int argc,char ** argv)656 exportcmd(int argc, char **argv)
657 {
658 struct var **vpp;
659 struct var *vp;
660 char *name;
661 char *p;
662 char *cmdname;
663 int ch, values;
664 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
665
666 cmdname = argv[0];
667 optreset = optind = 1;
668 opterr = 0;
669 values = 0;
670 while ((ch = getopt(argc, argv, "p")) != -1) {
671 switch (ch) {
672 case 'p':
673 values = 1;
674 break;
675 case '?':
676 default:
677 error("unknown option: -%c", optopt);
678 }
679 }
680 argc -= optind;
681 argv += optind;
682
683 if (values && argc != 0)
684 error("-p requires no arguments");
685 if (argc != 0) {
686 while ((name = *argv++) != NULL) {
687 if ((p = strchr(name, '=')) != NULL) {
688 p++;
689 } else {
690 vp = find_var(name, NULL, NULL);
691 if (vp != NULL) {
692 vp->flags |= flag;
693 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
694 change_env(vp->text, 1);
695 (void) setlocale(LC_ALL, "");
696 updatecharset();
697 }
698 continue;
699 }
700 }
701 setvar(name, p, flag);
702 }
703 } else {
704 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
705 for (vp = *vpp ; vp ; vp = vp->next) {
706 if (vp->flags & flag) {
707 if (values) {
708 /*
709 * Skip improper variable names
710 * so the output remains usable
711 * as shell input.
712 */
713 if (!isassignment(vp->text))
714 continue;
715 out1str(cmdname);
716 out1c(' ');
717 }
718 if (values && !(vp->flags & VUNSET)) {
719 outbin(vp->text,
720 vp->name_len + 1, out1);
721 out1qstr(vp->text +
722 vp->name_len + 1);
723 } else
724 outbin(vp->text, vp->name_len,
725 out1);
726 out1c('\n');
727 }
728 }
729 }
730 }
731 return 0;
732 }
733
734
735 /*
736 * The "local" command.
737 */
738
739 int
localcmd(int argc __unused,char ** argv __unused)740 localcmd(int argc __unused, char **argv __unused)
741 {
742 char *name;
743
744 if (! in_function())
745 error("Not in a function");
746 while ((name = *argptr++) != NULL) {
747 mklocal(name);
748 }
749 return 0;
750 }
751
752
753 /*
754 * Make a variable a local variable. When a variable is made local, it's
755 * value and flags are saved in a localvar structure. The saved values
756 * will be restored when the shell function returns. We handle the name
757 * "-" as a special case.
758 */
759
760 void
mklocal(char * name)761 mklocal(char *name)
762 {
763 struct localvar *lvp;
764 struct var **vpp;
765 struct var *vp;
766
767 INTOFF;
768 lvp = ckmalloc(sizeof (struct localvar));
769 if (name[0] == '-' && name[1] == '\0') {
770 lvp->text = ckmalloc(sizeof optlist);
771 memcpy(lvp->text, optlist, sizeof optlist);
772 vp = NULL;
773 } else {
774 vp = find_var(name, &vpp, NULL);
775 if (vp == NULL) {
776 if (strchr(name, '='))
777 setvareq(savestr(name), VSTRFIXED | VNOLOCAL);
778 else
779 setvar(name, NULL, VSTRFIXED | VNOLOCAL);
780 vp = *vpp; /* the new variable */
781 lvp->text = NULL;
782 lvp->flags = VUNSET;
783 } else {
784 lvp->text = vp->text;
785 lvp->flags = vp->flags;
786 vp->flags |= VSTRFIXED|VTEXTFIXED;
787 if (name[vp->name_len] == '=')
788 setvareq(savestr(name), VNOLOCAL);
789 }
790 }
791 lvp->vp = vp;
792 lvp->next = localvars;
793 localvars = lvp;
794 INTON;
795 }
796
797
798 /*
799 * Called after a function returns.
800 */
801
802 void
poplocalvars(void)803 poplocalvars(void)
804 {
805 struct localvar *lvp;
806 struct var *vp;
807
808 INTOFF;
809 while ((lvp = localvars) != NULL) {
810 localvars = lvp->next;
811 vp = lvp->vp;
812 if (vp == NULL) { /* $- saved */
813 memcpy(optlist, lvp->text, sizeof optlist);
814 ckfree(lvp->text);
815 optschanged();
816 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
817 (void)unsetvar(vp->text);
818 } else {
819 if ((vp->flags & VTEXTFIXED) == 0)
820 ckfree(vp->text);
821 vp->flags = lvp->flags;
822 vp->text = lvp->text;
823 }
824 ckfree(lvp);
825 }
826 INTON;
827 }
828
829
830 int
setvarcmd(int argc,char ** argv)831 setvarcmd(int argc, char **argv)
832 {
833 if (argc <= 2)
834 return unsetcmd(argc, argv);
835 else if (argc == 3)
836 setvar(argv[1], argv[2], 0);
837 else
838 error("too many arguments");
839 return 0;
840 }
841
842
843 /*
844 * The unset builtin command.
845 */
846
847 int
unsetcmd(int argc __unused,char ** argv __unused)848 unsetcmd(int argc __unused, char **argv __unused)
849 {
850 char **ap;
851 int i;
852 int flg_func = 0;
853 int flg_var = 0;
854 int ret = 0;
855
856 while ((i = nextopt("vf")) != '\0') {
857 if (i == 'f')
858 flg_func = 1;
859 else
860 flg_var = 1;
861 }
862 if (flg_func == 0 && flg_var == 0)
863 flg_var = 1;
864
865 INTOFF;
866 for (ap = argptr; *ap ; ap++) {
867 if (flg_func)
868 ret |= unsetfunc(*ap);
869 if (flg_var)
870 ret |= unsetvar(*ap);
871 }
872 INTON;
873 return ret;
874 }
875
876
877 /*
878 * Unset the specified variable.
879 * Called with interrupts off.
880 */
881
882 int
unsetvar(const char * s)883 unsetvar(const char *s)
884 {
885 struct var **vpp;
886 struct var *vp;
887
888 vp = find_var(s, &vpp, NULL);
889 if (vp == NULL)
890 return (0);
891 if (vp->flags & VREADONLY)
892 return (1);
893 if (vp->text[vp->name_len + 1] != '\0')
894 setvar(s, nullstr, 0);
895 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
896 change_env(s, 0);
897 setlocale(LC_ALL, "");
898 updatecharset();
899 }
900 vp->flags &= ~VEXPORT;
901 vp->flags |= VUNSET;
902 if ((vp->flags & VSTRFIXED) == 0) {
903 if ((vp->flags & VTEXTFIXED) == 0)
904 ckfree(vp->text);
905 *vpp = vp->next;
906 ckfree(vp);
907 }
908 return (0);
909 }
910
911
912
913 /*
914 * Returns true if the two strings specify the same varable. The first
915 * variable name is terminated by '='; the second may be terminated by
916 * either '=' or '\0'.
917 */
918
919 static int
varequal(const char * p,const char * q)920 varequal(const char *p, const char *q)
921 {
922 while (*p == *q++) {
923 if (*p++ == '=')
924 return 1;
925 }
926 if (*p == '=' && *(q - 1) == '\0')
927 return 1;
928 return 0;
929 }
930
931 /*
932 * Search for a variable.
933 * 'name' may be terminated by '=' or a NUL.
934 * vppp is set to the pointer to vp, or the list head if vp isn't found
935 * lenp is set to the number of charactets in 'name'
936 */
937
938 static struct var *
find_var(const char * name,struct var *** vppp,int * lenp)939 find_var(const char *name, struct var ***vppp, int *lenp)
940 {
941 unsigned int hashval;
942 int len;
943 struct var *vp, **vpp;
944 const char *p = name;
945
946 hashval = 0;
947 while (*p && *p != '=')
948 hashval = 2 * hashval + (unsigned char)*p++;
949 len = p - name;
950
951 if (lenp)
952 *lenp = len;
953 vpp = &vartab[hashval % VTABSIZE];
954 if (vppp)
955 *vppp = vpp;
956
957 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
958 if (vp->name_len != len)
959 continue;
960 if (memcmp(vp->text, name, len) != 0)
961 continue;
962 if (vppp)
963 *vppp = vpp;
964 return vp;
965 }
966 return NULL;
967 }
968