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
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36 * @(#)var.c 8.3 (Berkeley) 5/4/95
37 * $FreeBSD: src/bin/sh/var.c,v 1.15.2.2 2002/08/27 01:36:28 tjr Exp $
38 * $DragonFly: src/bin/sh/var.c,v 1.15 2007/01/14 17:29:58 pavalos Exp $
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,
108 "PATH=" _PATH_DEFPATH,
110 "PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/pkg/bin:/usr/pkg/sbin",
113 { &vppid, VSTRFIXED|VTEXTFIXED|VUNSET, "PPID=",
116 * vps1 depends on uid
118 { &vps2, VSTRFIXED|VTEXTFIXED, "PS2=> ",
120 { &vps4, VSTRFIXED|VTEXTFIXED, "PS4=+ ",
122 { &voptind, VSTRFIXED|VTEXTFIXED, "OPTIND=1",
128 STATIC struct var *vartab[VTABSIZE];
130 STATIC struct var **hashvar(const char *);
131 STATIC int varequal(const char *, const char *);
132 STATIC int localevar(const char *);
135 * Initialize the variable symbol tables and import the environment.
140 MKINIT char **environ;
145 for (envp = environ ; *envp ; envp++) {
146 if (strchr(*envp, '=')) {
147 setvareq(*envp, VEXPORT|VTEXTFIXED);
155 * This routine initializes the builtin variables. It is called when the
156 * shell is initialized and again when a shell procedure is spawned.
163 const struct varinit *ip;
167 for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
168 if ((vp->flags & VEXPORT) == 0) {
169 vpp = hashvar(ip->text);
172 vp->text = strdup(ip->text);
173 vp->flags = ip->flags;
180 if ((vps1.flags & VEXPORT) == 0) {
181 vpp = hashvar("PS1=");
184 vps1.text = strdup(geteuid() ? "PS1=$ " : "PS1=# ");
185 vps1.flags = VSTRFIXED|VTEXTFIXED;
187 if ((vppid.flags & VEXPORT) == 0) {
188 fmtstr(ppid, sizeof(ppid), "%d", (int)getppid());
189 setvarsafe("PPID", ppid, 0);
194 * Safe version of setvar, returns 1 on success 0 on failure.
198 setvarsafe(const char *name, const char *val, int flags)
200 struct jmploc jmploc;
201 struct jmploc *volatile savehandler = handler;
204 if (setjmp(jmploc.loc))
208 setvar(name, val, flags);
210 handler = savehandler;
215 * Set the value of a variable. The flags argument is stored with the
216 * flags of the variable. If val is NULL, the variable is unset.
220 setvar(const char *name, const char *val, int flags)
235 if (!is_in_name(*cp)) {
236 if (*cp == '\0' || *cp == '=')
244 error("%.*s: bad variable name", namelen, name);
245 len = namelen + 2; /* 2 is space for '=' and '\0' */
251 p = nameeq = ckmalloc(len);
253 while (--namelen >= 0)
259 setvareq(nameeq, flags);
263 localevar(const char *s)
265 static const char * const lnames[7] = {
266 "ALL", "COLLATE", "CTYPE", "MONETARY",
267 "NUMERIC", "TIME", NULL
269 const char * const *ss;
273 if (varequal(s + 1, "ANG"))
275 if (strncmp(s + 1, "C_", 2) != 0)
277 for (ss = lnames; *ss ; ss++)
278 if (varequal(s + 3, *ss))
284 * Same as setvar except that the variable and value are passed in
285 * the first argument as name=value. Since the first argument will
286 * be actually stored in the table, it should not be a string that
291 setvareq(char *s, int flags)
293 struct var *vp, **vpp;
299 for (vp = *vpp ; vp ; vp = vp->next) {
300 if (varequal(s, vp->text)) {
301 if (vp->flags & VREADONLY) {
302 len = strchr(s, '=') - s;
303 error("%.*s: is read only", len, s);
307 if (vp->func && (flags & VNOFUNC) == 0)
308 (*vp->func)(strchr(s, '=') + 1);
310 if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
313 vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
318 * We could roll this to a function, to handle it as
319 * a regular variable function callback, but why bother?
321 if (vp == &vmpath || (vp == &vmail && ! mpathset()))
323 if ((vp->flags & VEXPORT) && localevar(s)) {
325 error("putenv: cannot set %s", s);
326 setlocale(LC_ALL, "");
333 vp = ckmalloc(sizeof (*vp));
340 if ((vp->flags & VEXPORT) && localevar(s)) {
342 error("putenv: cannot set %s", s);
343 setlocale(LC_ALL, "");
351 * Process a linked list of variable assignments.
355 listsetvar(struct strlist *list)
360 for (lp = list ; lp ; lp = lp->next) {
361 setvareq(savestr(lp->text), 0);
369 * Find the value of a variable. Returns NULL if not set.
373 lookupvar(const char *name)
377 for (v = *hashvar(name) ; v ; v = v->next) {
378 if (varequal(v->text, name)) {
379 if (v->flags & VUNSET)
381 return strchr(v->text, '=') + 1;
390 * Search the environment of a builtin command. If the second argument
391 * is nonzero, return the value of a variable even if it hasn't been
396 bltinlookup(const char *name, int doall)
401 for (sp = cmdenviron ; sp ; sp = sp->next) {
402 if (varequal(sp->text, name))
403 return strchr(sp->text, '=') + 1;
405 for (v = *hashvar(name) ; v ; v = v->next) {
406 if (varequal(v->text, name)) {
407 if ((v->flags & VUNSET)
408 || (!doall && (v->flags & VEXPORT) == 0))
410 return strchr(v->text, '=') + 1;
419 * Generate a list of exported variables. This routine is used to construct
420 * the third argument to execve when executing a program.
432 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
433 for (vp = *vpp ; vp ; vp = vp->next)
434 if (vp->flags & VEXPORT)
437 ep = env = stalloc((nenv + 1) * sizeof *env);
438 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
439 for (vp = *vpp ; vp ; vp = vp->next)
440 if (vp->flags & VEXPORT)
449 * Called when a shell procedure is invoked to clear out nonexported
450 * variables. It is also necessary to reallocate variables of with
451 * VSTACK set since these are currently allocated on the stack.
455 void shprocvar(void);
466 struct var *vp, **prev;
468 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
469 for (prev = vpp ; (vp = *prev) != NULL ; ) {
470 if ((vp->flags & VEXPORT) == 0) {
472 if ((vp->flags & VTEXTFIXED) == 0)
474 if ((vp->flags & VSTRFIXED) == 0)
477 if (vp->flags & VSTACK) {
478 vp->text = savestr(vp->text);
479 vp->flags &=~ VSTACK;
490 var_compare(const void *a, const void *b)
492 const char *const *sa, *const *sb;
497 * This compares two var=value strings which creates a different
498 * order from what you would probably expect. POSIX is somewhat
499 * ambiguous on what should be sorted exactly.
501 return strcoll(*sa, *sb);
506 * Command to list all variables which are set. Currently this command
507 * is invoked from the set command when the set command is called without
512 showvarscmd(int argc __unused, char **argv __unused)
521 * POSIX requires us to sort the variables.
524 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
525 for (vp = *vpp; vp; vp = vp->next) {
526 if (!(vp->flags & VUNSET))
532 vars = ckmalloc(n * sizeof(*vars));
534 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
535 for (vp = *vpp; vp; vp = vp->next) {
536 if (!(vp->flags & VUNSET))
537 vars[i++] = vp->text;
541 qsort(vars, n, sizeof(*vars), var_compare);
542 for (i = 0; i < n; i++) {
543 for (s = vars[i]; *s != '='; s++)
558 * The export and readonly commands.
562 exportcmd(int argc, char **argv)
570 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
573 optreset = optind = 1;
576 while ((ch = getopt(argc, argv, "p")) != -1) {
583 error("unknown option: -%c", optopt);
589 if (values && argc != 0)
590 error("-p requires no arguments");
591 listsetvar(cmdenviron);
593 while ((name = *argv++) != NULL) {
594 if ((p = strchr(name, '=')) != NULL) {
598 for (vp = *vpp ; vp ; vp = vp->next) {
599 if (varequal(vp->text, name)) {
602 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
603 if (putenv(vp->text) != 0)
604 error("putenv: cannot set %s", vp->text);
605 setlocale(LC_ALL, "");
611 setvar(name, p, flag);
615 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
616 for (vp = *vpp ; vp ; vp = vp->next) {
617 if (vp->flags & flag) {
622 for (p = vp->text ; *p != '=' ; p++)
624 if (values && !(vp->flags & VUNSET)) {
638 * The "local" command.
642 localcmd(int argc __unused, char **argv __unused)
647 error("Not in a function");
648 while ((name = *argptr++) != NULL) {
656 * Make a variable a local variable. When a variable is made local, it's
657 * value and flags are saved in a localvar structure. The saved values
658 * will be restored when the shell function returns. We handle the name
659 * "-" as a special case.
665 struct localvar *lvp;
670 lvp = ckmalloc(sizeof (struct localvar));
671 if (name[0] == '-' && name[1] == '\0') {
672 lvp->text = ckmalloc(sizeof optlist);
673 memcpy(lvp->text, optlist, sizeof optlist);
677 for (vp = *vpp ; vp && ! varequal(vp->text, name) ; vp = vp->next);
679 if (strchr(name, '='))
680 setvareq(savestr(name), VSTRFIXED);
682 setvar(name, NULL, VSTRFIXED);
683 vp = *vpp; /* the new variable */
687 lvp->text = vp->text;
688 lvp->flags = vp->flags;
689 vp->flags |= VSTRFIXED|VTEXTFIXED;
690 if (strchr(name, '='))
691 setvareq(savestr(name), 0);
695 lvp->next = localvars;
702 * Called after a function returns.
708 struct localvar *lvp;
711 while ((lvp = localvars) != NULL) {
712 localvars = lvp->next;
714 if (vp == NULL) { /* $- saved */
715 memcpy(optlist, lvp->text, sizeof optlist);
717 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
720 if ((vp->flags & VTEXTFIXED) == 0)
722 vp->flags = lvp->flags;
723 vp->text = lvp->text;
731 setvarcmd(int argc, char **argv)
734 return unsetcmd(argc, argv);
736 setvar(argv[1], argv[2], 0);
738 error("List assignment not implemented");
744 * The unset builtin command. We unset the function before we unset the
745 * variable to allow a function to be unset when there is a readonly variable
746 * with the same name.
750 unsetcmd(int argc __unused, char **argv __unused)
758 while ((i = nextopt("vf")) != '\0') {
764 if (flg_func == 0 && flg_var == 0)
767 for (ap = argptr; *ap ; ap++) {
769 ret |= unsetfunc(*ap);
771 ret |= unsetvar(*ap);
778 * Unset the specified variable.
782 unsetvar(const char *s)
788 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
789 if (varequal(vp->text, s)) {
790 if (vp->flags & VREADONLY)
793 if (*(strchr(vp->text, '=') + 1) != '\0')
794 setvar(s, nullstr, 0);
795 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
797 setlocale(LC_ALL, "");
799 vp->flags &= ~VEXPORT;
801 if ((vp->flags & VSTRFIXED) == 0) {
802 if ((vp->flags & VTEXTFIXED) == 0)
817 * Find the appropriate entry in the hash table from the name.
821 hashvar(const char *p)
823 unsigned int hashval;
825 hashval = ((unsigned char) *p) << 4;
826 while (*p && *p != '=')
827 hashval += (unsigned char) *p++;
828 return &vartab[hashval % VTABSIZE];
834 * Returns true if the two strings specify the same varable. The first
835 * variable name is terminated by '='; the second may be terminated by
836 * either '=' or '\0'.
840 varequal(const char *p, const char *q)
846 if (*p == '=' && *(q - 1) == '\0')