2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
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11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 static char sccsid[] = "@(#)var.c 8.3 (Berkeley) 5/4/95";
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
57 #include "nodes.h" /* for other headers */
58 #include "eval.h" /* defines cmdenviron */
70 #include "myhistedit.h"
83 void (*func)(const char *);
98 static struct var voptind;
101 struct localvar *localvars;
104 static const struct varinit varinit[] = {
106 { &vhistsize, VUNSET, "HISTSIZE=",
109 { &vifs, 0, "IFS= \t\n",
111 { &vmail, VUNSET, "MAIL=",
113 { &vmpath, VUNSET, "MAILPATH=",
115 { &vpath, 0, "PATH=" _PATH_DEFPATH,
118 * vps1 depends on uid
120 { &vps2, 0, "PS2=> ",
122 { &vps4, 0, "PS4=+ ",
125 { &vterm, VUNSET, "TERM=",
128 { &voptind, 0, "OPTIND=1",
130 { &vdisvfork, VUNSET, "SH_DISABLE_VFORK=",
136 static struct var *vartab[VTABSIZE];
138 static const char *const locale_names[7] = {
139 "LC_COLLATE", "LC_CTYPE", "LC_MONETARY",
140 "LC_NUMERIC", "LC_TIME", "LC_MESSAGES", NULL
142 static const int locale_categories[7] = {
143 LC_COLLATE, LC_CTYPE, LC_MONETARY, LC_NUMERIC, LC_TIME, LC_MESSAGES, 0
146 static int varequal(const char *, const char *);
147 static struct var *find_var(const char *, struct var ***, int *);
148 static int localevar(const char *);
149 static void setvareq_const(const char *s, int flags);
151 extern char **environ;
154 * This routine initializes the builtin variables and imports the environment.
155 * It is called when the shell is initialized.
162 const struct varinit *ip;
167 for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
168 if (find_var(ip->text, &vpp, &vp->name_len) != NULL)
172 vp->text = __DECONST(char *, ip->text);
173 vp->flags = ip->flags | VSTRFIXED | VTEXTFIXED;
179 if (find_var("PS1", &vpp, &vps1.name_len) == NULL) {
182 vps1.text = __DECONST(char *, geteuid() ? "PS1=$ " : "PS1=# ");
183 vps1.flags = VSTRFIXED|VTEXTFIXED;
185 fmtstr(ppid, sizeof(ppid), "%d", (int)getppid());
186 setvarsafe("PPID", ppid, 0);
187 for (envp = environ ; *envp ; envp++) {
188 if (strchr(*envp, '=')) {
189 setvareq(*envp, VEXPORT|VTEXTFIXED);
192 setvareq_const("OPTIND=1", 0);
193 setvareq_const("IFS= \t\n", 0);
197 * Safe version of setvar, returns 1 on success 0 on failure.
201 setvarsafe(const char *name, const char *val, int flags)
203 struct jmploc jmploc;
204 struct jmploc *const savehandler = handler;
209 if (setjmp(jmploc.loc))
213 setvar(name, val, flags);
215 handler = savehandler;
221 * Set the value of a variable. The flags argument is stored with the
222 * flags of the variable. If val is NULL, the variable is unset.
226 setvar(const char *name, const char *val, int flags)
241 if (! is_in_name(*p)) {
242 if (*p == '\0' || *p == '=')
250 error("%.*s: bad variable name", (int)namelen, name);
251 len = namelen + 2; /* 2 is space for '=' and '\0' */
256 vallen = strlen(val);
260 nameeq = ckmalloc(len);
261 memcpy(nameeq, name, namelen);
262 nameeq[namelen] = '=';
264 memcpy(nameeq + namelen + 1, val, vallen + 1);
266 nameeq[namelen + 1] = '\0';
267 setvareq(nameeq, flags);
272 localevar(const char *s)
274 const char *const *ss;
278 if (varequal(s + 1, "ANG"))
280 if (strncmp(s + 1, "C_", 2) != 0)
282 if (varequal(s + 3, "ALL"))
284 for (ss = locale_names; *ss ; ss++)
285 if (varequal(s + 3, *ss + 3))
292 * Sets/unsets an environment variable from a pointer that may actually be a
293 * pointer into environ where the string should not be manipulated.
296 change_env(const char *s, int set)
303 if ((eqp = strchr(ss, '=')) != NULL)
305 if (set && eqp != NULL)
306 (void) setenv(ss, eqp + 1, 1);
317 * Same as setvar except that the variable and value are passed in
318 * the first argument as name=value. Since the first argument will
319 * be actually stored in the table, it should not be a string that
324 setvareq(char *s, int flags)
326 struct var *vp, **vpp;
331 if (forcelocal && !(flags & (VNOSET | VNOLOCAL)))
333 vp = find_var(s, &vpp, &nlen);
335 if (vp->flags & VREADONLY) {
336 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
338 error("%.*s: is read only", vp->name_len, vp->text);
340 if (flags & VNOSET) {
341 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
347 if (vp->func && (flags & VNOFUNC) == 0)
348 (*vp->func)(s + vp->name_len + 1);
350 if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
353 vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
358 * We could roll this to a function, to handle it as
359 * a regular variable function callback, but why bother?
361 * Note: this assumes iflag is not set to 1 initially.
362 * As part of initvar(), this is called before arguments
365 if ((vp == &vmpath || (vp == &vmail && ! mpathset())) &&
368 if ((vp->flags & VEXPORT) && localevar(s)) {
370 (void) setlocale(LC_ALL, "");
377 if (flags & VNOSET) {
378 if ((flags & (VTEXTFIXED|VSTACK)) == 0)
383 vp = ckmalloc(sizeof (*vp));
390 if ((vp->flags & VEXPORT) && localevar(s)) {
392 (void) setlocale(LC_ALL, "");
400 setvareq_const(const char *s, int flags)
402 setvareq(__DECONST(char *, s), flags | VTEXTFIXED);
407 * Process a linked list of variable assignments.
411 listsetvar(struct arglist *list, int flags)
416 for (i = 0; i < list->count; i++)
417 setvareq(savestr(list->args[i]), flags);
424 * Find the value of a variable. Returns NULL if not set.
428 lookupvar(const char *name)
432 v = find_var(name, NULL, NULL);
433 if (v == NULL || v->flags & VUNSET)
435 return v->text + v->name_len + 1;
441 * Search the environment of a builtin command. If the second argument
442 * is nonzero, return the value of a variable even if it hasn't been
447 bltinlookup(const char *name, int doall)
454 if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) {
455 if (varequal(cmdenviron->args[i], name))
456 result = strchr(cmdenviron->args[i], '=') + 1;
461 v = find_var(name, NULL, NULL);
462 if (v == NULL || v->flags & VUNSET ||
463 (!doall && (v->flags & VEXPORT) == 0))
465 return v->text + v->name_len + 1;
470 * Set up locale for a builtin (LANG/LC_* assignments).
479 if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) {
480 if (localevar(cmdenviron->args[i])) {
487 loc = bltinlookup("LC_ALL", 0);
490 setlocale(LC_ALL, loc);
495 locdef = bltinlookup("LANG", 0);
496 for (i = 0; locale_names[i] != NULL; i++) {
497 loc = bltinlookup(locale_names[i], 0);
501 setlocale(locale_categories[i], loc);
508 * Undo the effect of bltinlocaleset().
511 bltinunsetlocale(void)
516 if (cmdenviron) for (i = 0; i < cmdenviron->count; i++) {
517 if (localevar(cmdenviron->args[i])) {
518 setlocale(LC_ALL, "");
527 * Update the localeisutf8 flag.
534 charset = nl_langinfo(CODESET);
535 localeisutf8 = !strcmp(charset, "UTF-8");
542 initial_localeisutf8 = localeisutf8;
546 * Generate a list of exported variables. This routine is used to construct
547 * the third argument to execve when executing a program.
559 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
560 for (vp = *vpp ; vp ; vp = vp->next)
561 if (vp->flags & VEXPORT)
564 ep = env = stalloc((nenv + 1) * sizeof *env);
565 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
566 for (vp = *vpp ; vp ; vp = vp->next)
567 if (vp->flags & VEXPORT)
576 var_compare(const void *a, const void *b)
578 const char *const *sa, *const *sb;
583 * This compares two var=value strings which creates a different
584 * order from what you would probably expect. POSIX is somewhat
585 * ambiguous on what should be sorted exactly.
587 return strcoll(*sa, *sb);
592 * Command to list all variables which are set. This is invoked from the
593 * set command when it is called without any options or operands.
597 showvarscmd(int argc __unused, char **argv __unused)
606 * POSIX requires us to sort the variables.
609 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
610 for (vp = *vpp; vp; vp = vp->next) {
611 if (!(vp->flags & VUNSET))
617 vars = ckmalloc(n * sizeof(*vars));
619 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
620 for (vp = *vpp; vp; vp = vp->next) {
621 if (!(vp->flags & VUNSET))
622 vars[i++] = vp->text;
626 qsort(vars, n, sizeof(*vars), var_compare);
627 for (i = 0; i < n; i++) {
629 * Skip improper variable names so the output remains usable as
632 if (!isassignment(vars[i]))
634 s = strchr(vars[i], '=');
636 outbin(vars[i], s - vars[i], out1);
649 * The export and readonly commands.
653 exportcmd(int argc __unused, char **argv)
662 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
666 while ((ch = nextopt("p")) != '\0') {
674 if (values && *argptr != NULL)
675 error("-p requires no arguments");
676 if (*argptr != NULL) {
677 for (ap = argptr; (name = *ap) != NULL; ap++) {
678 if ((p = strchr(name, '=')) != NULL) {
681 vp = find_var(name, NULL, NULL);
684 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
685 change_env(vp->text, 1);
686 (void) setlocale(LC_ALL, "");
692 setvar(name, p, flag);
695 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
696 for (vp = *vpp ; vp ; vp = vp->next) {
697 if (vp->flags & flag) {
700 * Skip improper variable names
701 * so the output remains usable
704 if (!isassignment(vp->text))
709 if (values && !(vp->flags & VUNSET)) {
711 vp->name_len + 1, out1);
715 outbin(vp->text, vp->name_len,
727 * The "local" command.
731 localcmd(int argc __unused, char **argv __unused)
737 error("Not in a function");
738 while ((name = *argptr++) != NULL) {
746 * Make a variable a local variable. When a variable is made local, it's
747 * value and flags are saved in a localvar structure. The saved values
748 * will be restored when the shell function returns. We handle the name
749 * "-" as a special case.
755 struct localvar *lvp;
760 lvp = ckmalloc(sizeof (struct localvar));
761 if (name[0] == '-' && name[1] == '\0') {
762 lvp->text = ckmalloc(sizeof optval);
763 memcpy(lvp->text, optval, sizeof optval);
766 vp = find_var(name, &vpp, NULL);
768 if (strchr(name, '='))
769 setvareq(savestr(name), VSTRFIXED | VNOLOCAL);
771 setvar(name, NULL, VSTRFIXED | VNOLOCAL);
772 vp = *vpp; /* the new variable */
776 lvp->text = vp->text;
777 lvp->flags = vp->flags;
778 vp->flags |= VSTRFIXED|VTEXTFIXED;
779 if (name[vp->name_len] == '=')
780 setvareq(savestr(name), VNOLOCAL);
784 lvp->next = localvars;
791 * Called after a function returns.
797 struct localvar *lvp;
802 while ((lvp = localvars) != NULL) {
803 localvars = lvp->next;
805 if (vp == NULL) { /* $- saved */
806 memcpy(optval, lvp->text, sizeof optval);
809 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
810 vp->flags &= ~VREADONLY;
811 (void)unsetvar(vp->text);
813 islocalevar = (vp->flags | lvp->flags) & VEXPORT &&
814 localevar(lvp->text);
815 if ((vp->flags & VTEXTFIXED) == 0)
817 vp->flags = lvp->flags;
818 vp->text = lvp->text;
820 (*vp->func)(vp->text + vp->name_len + 1);
822 change_env(vp->text, vp->flags & VEXPORT &&
823 (vp->flags & VUNSET) == 0);
824 setlocale(LC_ALL, "");
835 setvarcmd(int argc, char **argv)
838 return unsetcmd(argc, argv);
840 setvar(argv[1], argv[2], 0);
842 error("too many arguments");
848 * The unset builtin command.
852 unsetcmd(int argc __unused, char **argv __unused)
860 while ((i = nextopt("vf")) != '\0') {
866 if (flg_func == 0 && flg_var == 0)
870 for (ap = argptr; *ap ; ap++) {
872 ret |= unsetfunc(*ap);
874 ret |= unsetvar(*ap);
882 * Unset the specified variable.
883 * Called with interrupts off.
887 unsetvar(const char *s)
892 vp = find_var(s, &vpp, NULL);
895 if (vp->flags & VREADONLY)
897 if (vp->text[vp->name_len + 1] != '\0')
899 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
901 setlocale(LC_ALL, "");
904 vp->flags &= ~VEXPORT;
906 if ((vp->flags & VSTRFIXED) == 0) {
907 if ((vp->flags & VTEXTFIXED) == 0)
918 * Returns true if the two strings specify the same variable. The first
919 * variable name is terminated by '='; the second may be terminated by
920 * either '=' or '\0'.
924 varequal(const char *p, const char *q)
930 if (*p == '=' && *(q - 1) == '\0')
936 * Search for a variable.
937 * 'name' may be terminated by '=' or a NUL.
938 * vppp is set to the pointer to vp, or the list head if vp isn't found
939 * lenp is set to the number of characters in 'name'
943 find_var(const char *name, struct var ***vppp, int *lenp)
945 unsigned int hashval;
947 struct var *vp, **vpp;
948 const char *p = name;
951 while (*p && *p != '=')
952 hashval = 2 * hashval + (unsigned char)*p++;
957 vpp = &vartab[hashval % VTABSIZE];
961 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
962 if (vp->name_len != len)
964 if (memcmp(vp->text, name, len) != 0)