2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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)
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29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
54 #include "nodes.h" /* for other headers */
55 #include "eval.h" /* defines cmdenviron */
66 #include "myhistedit.h"
77 void (*func)(const char *);
93 STATIC struct var voptind;
95 STATIC const struct varinit varinit[] = {
97 { &vhistsize, VSTRFIXED|VTEXTFIXED|VUNSET, "HISTSIZE=",
100 { &vifs, VSTRFIXED|VTEXTFIXED, "IFS= \t\n",
102 { &vmail, VSTRFIXED|VTEXTFIXED|VUNSET, "MAIL=",
104 { &vmpath, VSTRFIXED|VTEXTFIXED|VUNSET, "MAILPATH=",
106 { &vpath, VSTRFIXED|VTEXTFIXED, "PATH=" _PATH_DEFPATH,
108 { &vppid, VSTRFIXED|VTEXTFIXED|VUNSET, "PPID=",
111 * vps1 depends on uid
113 { &vps2, VSTRFIXED|VTEXTFIXED, "PS2=> ",
115 { &vps4, VSTRFIXED|VTEXTFIXED, "PS4=+ ",
117 { &voptind, VSTRFIXED|VTEXTFIXED, "OPTIND=1",
123 STATIC struct var *vartab[VTABSIZE];
125 STATIC struct var **hashvar(char *);
126 STATIC int varequal(char *, char *);
127 STATIC int localevar(char *);
130 * Initialize the variable symbol tables and import the environment.
137 extern char **environ;
140 for (envp = environ ; *envp ; envp++) {
141 if (strchr(*envp, '=')) {
142 setvareq(*envp, VEXPORT|VTEXTFIXED);
150 * This routine initializes the builtin variables. It is called when the
151 * shell is initialized and again when a shell procedure is spawned.
158 const struct varinit *ip;
162 for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
163 if ((vp->flags & VEXPORT) == 0) {
164 vpp = hashvar(ip->text);
168 vp->flags = ip->flags;
175 if ((vps1.flags & VEXPORT) == 0) {
176 vpp = hashvar("PS1=");
179 vps1.text = geteuid() ? "PS1=$ " : "PS1=# ";
180 vps1.flags = VSTRFIXED|VTEXTFIXED;
182 if ((vppid.flags & VEXPORT) == 0) {
183 fmtstr(ppid, sizeof(ppid), "%d", (int)getppid());
184 setvarsafe("PPID", ppid, 0);
189 * Safe version of setvar, returns 1 on success 0 on failure.
193 setvarsafe(char *name, char *val, int flags)
195 struct jmploc jmploc;
196 struct jmploc *const savehandler = handler;
199 if (setjmp(jmploc.loc))
203 setvar(name, val, flags);
205 handler = savehandler;
210 * Set the value of a variable. The flags argument is stored with the
211 * flags of the variable. If val is NULL, the variable is unset.
215 setvar(char *name, char *val, int flags)
229 if (! is_in_name(*p)) {
230 if (*p == '\0' || *p == '=')
238 error("%.*s: bad variable name", namelen, name);
239 len = namelen + 2; /* 2 is space for '=' and '\0' */
245 p = nameeq = ckmalloc(len);
247 while (--namelen >= 0)
253 setvareq(nameeq, flags);
259 static char *lnames[7] = {
260 "ALL", "COLLATE", "CTYPE", "MONETARY",
261 "NUMERIC", "TIME", NULL
267 if (varequal(s + 1, "ANG"))
269 if (strncmp(s + 1, "C_", 2) != 0)
271 for (ss = lnames; *ss ; ss++)
272 if (varequal(s + 3, *ss))
279 * Sets/unsets an environment variable from a pointer that may actually be a
280 * pointer into environ where the string should not be manipulated.
283 change_env(char *s, int set)
289 if ((eqp = strchr(ss, '=')) != NULL)
291 if (set && eqp != NULL)
292 (void) setenv(ss, eqp + 1, 1);
302 * Same as setvar except that the variable and value are passed in
303 * the first argument as name=value. Since the first argument will
304 * be actually stored in the table, it should not be a string that
309 setvareq(char *s, int flags)
311 struct var *vp, **vpp;
317 for (vp = *vpp ; vp ; vp = vp->next) {
318 if (varequal(s, vp->text)) {
319 if (vp->flags & VREADONLY) {
320 len = strchr(s, '=') - s;
321 error("%.*s: is read only", len, s);
325 if (vp->func && (flags & VNOFUNC) == 0)
326 (*vp->func)(strchr(s, '=') + 1);
328 if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
331 vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
336 * We could roll this to a function, to handle it as
337 * a regular variable function callback, but why bother?
339 if (vp == &vmpath || (vp == &vmail && ! mpathset()))
341 if ((vp->flags & VEXPORT) && localevar(s)) {
343 (void) setlocale(LC_ALL, "");
350 vp = ckmalloc(sizeof (*vp));
357 if ((vp->flags & VEXPORT) && localevar(s)) {
359 (void) setlocale(LC_ALL, "");
367 * Process a linked list of variable assignments.
371 listsetvar(struct strlist *list)
376 for (lp = list ; lp ; lp = lp->next) {
377 setvareq(savestr(lp->text), 0);
385 * Find the value of a variable. Returns NULL if not set.
389 lookupvar(char *name)
393 for (v = *hashvar(name) ; v ; v = v->next) {
394 if (varequal(v->text, name)) {
395 if (v->flags & VUNSET)
397 return strchr(v->text, '=') + 1;
406 * Search the environment of a builtin command. If the second argument
407 * is nonzero, return the value of a variable even if it hasn't been
412 bltinlookup(char *name, int doall)
417 for (sp = cmdenviron ; sp ; sp = sp->next) {
418 if (varequal(sp->text, name))
419 return strchr(sp->text, '=') + 1;
421 for (v = *hashvar(name) ; v ; v = v->next) {
422 if (varequal(v->text, name)) {
423 if ((v->flags & VUNSET)
424 || (!doall && (v->flags & VEXPORT) == 0))
426 return strchr(v->text, '=') + 1;
435 * Generate a list of exported variables. This routine is used to construct
436 * the third argument to execve when executing a program.
448 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
449 for (vp = *vpp ; vp ; vp = vp->next)
450 if (vp->flags & VEXPORT)
453 ep = env = stalloc((nenv + 1) * sizeof *env);
454 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
455 for (vp = *vpp ; vp ; vp = vp->next)
456 if (vp->flags & VEXPORT)
465 * Called when a shell procedure is invoked to clear out nonexported
466 * variables. It is also necessary to reallocate variables of with
467 * VSTACK set since these are currently allocated on the stack.
471 MKINIT void shprocvar(void);
482 struct var *vp, **prev;
484 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
485 for (prev = vpp ; (vp = *prev) != NULL ; ) {
486 if ((vp->flags & VEXPORT) == 0) {
488 if ((vp->flags & VTEXTFIXED) == 0)
490 if ((vp->flags & VSTRFIXED) == 0)
493 if (vp->flags & VSTACK) {
494 vp->text = savestr(vp->text);
495 vp->flags &=~ VSTACK;
506 var_compare(const void *a, const void *b)
508 const char *const *sa, *const *sb;
513 * This compares two var=value strings which creates a different
514 * order from what you would probably expect. POSIX is somewhat
515 * ambiguous on what should be sorted exactly.
517 return strcoll(*sa, *sb);
522 * Command to list all variables which are set. Currently this command
523 * is invoked from the set command when the set command is called without
528 showvarscmd(int argc __unused, char **argv __unused)
537 * POSIX requires us to sort the variables.
540 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
541 for (vp = *vpp; vp; vp = vp->next) {
542 if (!(vp->flags & VUNSET))
548 vars = ckmalloc(n * sizeof(*vars));
550 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
551 for (vp = *vpp; vp; vp = vp->next) {
552 if (!(vp->flags & VUNSET))
553 vars[i++] = vp->text;
557 qsort(vars, n, sizeof(*vars), var_compare);
558 for (i = 0; i < n; i++) {
559 for (s = vars[i]; *s != '='; s++)
574 * The export and readonly commands.
578 exportcmd(int argc, char **argv)
586 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
589 optreset = optind = 1;
592 while ((ch = getopt(argc, argv, "p")) != -1) {
599 error("unknown option: -%c", optopt);
605 if (values && argc != 0)
606 error("-p requires no arguments");
607 listsetvar(cmdenviron);
609 while ((name = *argv++) != NULL) {
610 if ((p = strchr(name, '=')) != NULL) {
614 for (vp = *vpp ; vp ; vp = vp->next) {
615 if (varequal(vp->text, name)) {
618 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
619 change_env(vp->text, 1);
620 (void) setlocale(LC_ALL, "");
626 setvar(name, p, flag);
630 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
631 for (vp = *vpp ; vp ; vp = vp->next) {
632 if (vp->flags & flag) {
637 for (p = vp->text ; *p != '=' ; p++)
639 if (values && !(vp->flags & VUNSET)) {
653 * The "local" command.
657 localcmd(int argc __unused, char **argv __unused)
662 error("Not in a function");
663 while ((name = *argptr++) != NULL) {
671 * Make a variable a local variable. When a variable is made local, it's
672 * value and flags are saved in a localvar structure. The saved values
673 * will be restored when the shell function returns. We handle the name
674 * "-" as a special case.
680 struct localvar *lvp;
685 lvp = ckmalloc(sizeof (struct localvar));
686 if (name[0] == '-' && name[1] == '\0') {
687 lvp->text = ckmalloc(sizeof optlist);
688 memcpy(lvp->text, optlist, sizeof optlist);
692 for (vp = *vpp ; vp && ! varequal(vp->text, name) ; vp = vp->next);
694 if (strchr(name, '='))
695 setvareq(savestr(name), VSTRFIXED);
697 setvar(name, NULL, VSTRFIXED);
698 vp = *vpp; /* the new variable */
702 lvp->text = vp->text;
703 lvp->flags = vp->flags;
704 vp->flags |= VSTRFIXED|VTEXTFIXED;
705 if (strchr(name, '='))
706 setvareq(savestr(name), 0);
710 lvp->next = localvars;
717 * Called after a function returns.
723 struct localvar *lvp;
726 while ((lvp = localvars) != NULL) {
727 localvars = lvp->next;
729 if (vp == NULL) { /* $- saved */
730 memcpy(optlist, lvp->text, sizeof optlist);
732 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
733 (void)unsetvar(vp->text);
735 if ((vp->flags & VTEXTFIXED) == 0)
737 vp->flags = lvp->flags;
738 vp->text = lvp->text;
746 setvarcmd(int argc, char **argv)
749 return unsetcmd(argc, argv);
751 setvar(argv[1], argv[2], 0);
753 error("List assignment not implemented");
759 * The unset builtin command. We unset the function before we unset the
760 * variable to allow a function to be unset when there is a readonly variable
761 * with the same name.
765 unsetcmd(int argc __unused, char **argv __unused)
773 while ((i = nextopt("vf")) != '\0') {
779 if (flg_func == 0 && flg_var == 0)
782 for (ap = argptr; *ap ; ap++) {
784 ret |= unsetfunc(*ap);
786 ret |= unsetvar(*ap);
793 * Unset the specified variable.
803 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
804 if (varequal(vp->text, s)) {
805 if (vp->flags & VREADONLY)
808 if (*(strchr(vp->text, '=') + 1) != '\0')
809 setvar(s, nullstr, 0);
810 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
812 setlocale(LC_ALL, "");
814 vp->flags &= ~VEXPORT;
816 if ((vp->flags & VSTRFIXED) == 0) {
817 if ((vp->flags & VTEXTFIXED) == 0)
833 * Find the appropriate entry in the hash table from the name.
839 unsigned int hashval;
841 hashval = ((unsigned char) *p) << 4;
842 while (*p && *p != '=')
843 hashval += (unsigned char) *p++;
844 return &vartab[hashval % VTABSIZE];
850 * Returns true if the two strings specify the same varable. The first
851 * variable name is terminated by '='; the second may be terminated by
852 * either '=' or '\0'.
856 varequal(char *p, char *q)
862 if (*p == '=' && *(q - 1) == '\0')