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|VEXPORT,
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 * Sets/unsets an environment variable from a pointer that may actually be a
285 * pointer into environ where the string should not be manipulated.
288 change_env(char *s, int set)
294 if ((eqp = strchr(ss, '=')) != NULL)
296 if (set && eqp != NULL) {
297 if (setenv(ss, eqp + 1, 1) != 0)
298 error("setenv: cannot set %s=%s", ss, eqp + 1);
306 * Same as setvar except that the variable and value are passed in
307 * the first argument as name=value. Since the first argument will
308 * be actually stored in the table, it should not be a string that
313 setvareq(char *s, int flags)
315 struct var *vp, **vpp;
321 for (vp = *vpp ; vp ; vp = vp->next) {
322 if (varequal(s, vp->text)) {
323 if (vp->flags & VREADONLY) {
324 len = strchr(s, '=') - s;
325 error("%.*s: is read only", len, s);
329 if (vp->func && (flags & VNOFUNC) == 0)
330 (*vp->func)(strchr(s, '=') + 1);
332 if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
335 vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
340 * We could roll this to a function, to handle it as
341 * a regular variable function callback, but why bother?
343 if (vp == &vmpath || (vp == &vmail && ! mpathset()))
345 if ((vp->flags & VEXPORT) && localevar(s)) {
347 setlocale(LC_ALL, "");
354 vp = ckmalloc(sizeof (*vp));
361 if ((vp->flags & VEXPORT) && localevar(s)) {
363 setlocale(LC_ALL, "");
371 * Process a linked list of variable assignments.
375 listsetvar(struct strlist *list)
380 for (lp = list ; lp ; lp = lp->next) {
381 setvareq(savestr(lp->text), 0);
389 * Find the value of a variable. Returns NULL if not set.
393 lookupvar(const char *name)
397 for (v = *hashvar(name) ; v ; v = v->next) {
398 if (varequal(v->text, name)) {
399 if (v->flags & VUNSET)
401 return strchr(v->text, '=') + 1;
410 * Search the environment of a builtin command. If the second argument
411 * is nonzero, return the value of a variable even if it hasn't been
416 bltinlookup(const char *name, int doall)
421 for (sp = cmdenviron ; sp ; sp = sp->next) {
422 if (varequal(sp->text, name))
423 return strchr(sp->text, '=') + 1;
425 for (v = *hashvar(name) ; v ; v = v->next) {
426 if (varequal(v->text, name)) {
427 if ((v->flags & VUNSET)
428 || (!doall && (v->flags & VEXPORT) == 0))
430 return strchr(v->text, '=') + 1;
439 * Generate a list of exported variables. This routine is used to construct
440 * the third argument to execve when executing a program.
452 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
453 for (vp = *vpp ; vp ; vp = vp->next)
454 if (vp->flags & VEXPORT)
457 ep = env = stalloc((nenv + 1) * sizeof *env);
458 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
459 for (vp = *vpp ; vp ; vp = vp->next)
460 if (vp->flags & VEXPORT)
469 * Called when a shell procedure is invoked to clear out nonexported
470 * variables. It is also necessary to reallocate variables of with
471 * VSTACK set since these are currently allocated on the stack.
475 void shprocvar(void);
486 struct var *vp, **prev;
488 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
489 for (prev = vpp ; (vp = *prev) != NULL ; ) {
490 if ((vp->flags & VEXPORT) == 0) {
492 if ((vp->flags & VTEXTFIXED) == 0)
494 if ((vp->flags & VSTRFIXED) == 0)
497 if (vp->flags & VSTACK) {
498 vp->text = savestr(vp->text);
499 vp->flags &=~ VSTACK;
510 var_compare(const void *a, const void *b)
512 const char *const *sa, *const *sb;
517 * This compares two var=value strings which creates a different
518 * order from what you would probably expect. POSIX is somewhat
519 * ambiguous on what should be sorted exactly.
521 return strcoll(*sa, *sb);
526 * Command to list all variables which are set. Currently this command
527 * is invoked from the set command when the set command is called without
532 showvarscmd(int argc __unused, char **argv __unused)
541 * POSIX requires us to sort the variables.
544 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
545 for (vp = *vpp; vp; vp = vp->next) {
546 if (!(vp->flags & VUNSET))
552 vars = ckmalloc(n * sizeof(*vars));
554 for (vpp = vartab; vpp < vartab + VTABSIZE; vpp++) {
555 for (vp = *vpp; vp; vp = vp->next) {
556 if (!(vp->flags & VUNSET))
557 vars[i++] = vp->text;
561 qsort(vars, n, sizeof(*vars), var_compare);
562 for (i = 0; i < n; i++) {
563 for (s = vars[i]; *s != '='; s++)
578 * The export and readonly commands.
582 exportcmd(int argc, char **argv)
590 int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
593 optreset = optind = 1;
596 while ((ch = getopt(argc, argv, "p")) != -1) {
603 error("unknown option: -%c", optopt);
609 if (values && argc != 0)
610 error("-p requires no arguments");
611 listsetvar(cmdenviron);
613 while ((name = *argv++) != NULL) {
614 if ((p = strchr(name, '=')) != NULL) {
618 for (vp = *vpp ; vp ; vp = vp->next) {
619 if (varequal(vp->text, name)) {
622 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
623 change_env(vp->text, 1);
624 setlocale(LC_ALL, "");
630 setvar(name, p, flag);
634 for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
635 for (vp = *vpp ; vp ; vp = vp->next) {
636 if (vp->flags & flag) {
641 for (p = vp->text ; *p != '=' ; p++)
643 if (values && !(vp->flags & VUNSET)) {
657 * The "local" command.
661 localcmd(int argc __unused, char **argv __unused)
666 error("Not in a function");
667 while ((name = *argptr++) != NULL) {
675 * Make a variable a local variable. When a variable is made local, it's
676 * value and flags are saved in a localvar structure. The saved values
677 * will be restored when the shell function returns. We handle the name
678 * "-" as a special case.
684 struct localvar *lvp;
689 lvp = ckmalloc(sizeof (struct localvar));
690 if (name[0] == '-' && name[1] == '\0') {
691 lvp->text = ckmalloc(sizeof optlist);
692 memcpy(lvp->text, optlist, sizeof optlist);
696 for (vp = *vpp ; vp && ! varequal(vp->text, name) ; vp = vp->next);
698 if (strchr(name, '='))
699 setvareq(savestr(name), VSTRFIXED);
701 setvar(name, NULL, VSTRFIXED);
702 vp = *vpp; /* the new variable */
706 lvp->text = vp->text;
707 lvp->flags = vp->flags;
708 vp->flags |= VSTRFIXED|VTEXTFIXED;
709 if (strchr(name, '='))
710 setvareq(savestr(name), 0);
714 lvp->next = localvars;
721 * Called after a function returns.
727 struct localvar *lvp;
730 while ((lvp = localvars) != NULL) {
731 localvars = lvp->next;
733 if (vp == NULL) { /* $- saved */
734 memcpy(optlist, lvp->text, sizeof optlist);
736 } else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
739 if ((vp->flags & VTEXTFIXED) == 0)
741 vp->flags = lvp->flags;
742 vp->text = lvp->text;
750 setvarcmd(int argc, char **argv)
753 return unsetcmd(argc, argv);
755 setvar(argv[1], argv[2], 0);
757 error("List assignment not implemented");
763 * The unset builtin command. We unset the function before we unset the
764 * variable to allow a function to be unset when there is a readonly variable
765 * with the same name.
769 unsetcmd(int argc __unused, char **argv __unused)
777 while ((i = nextopt("vf")) != '\0') {
783 if (flg_func == 0 && flg_var == 0)
786 for (ap = argptr; *ap ; ap++) {
788 ret |= unsetfunc(*ap);
790 ret |= unsetvar(*ap);
797 * Unset the specified variable.
801 unsetvar(const char *s)
807 for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
808 if (varequal(vp->text, s)) {
809 if (vp->flags & VREADONLY)
812 if (*(strchr(vp->text, '=') + 1) != '\0')
813 setvar(s, nullstr, 0);
814 if ((vp->flags & VEXPORT) && localevar(vp->text)) {
815 change_env(__DECONST(char *, s), 0);
816 setlocale(LC_ALL, "");
818 vp->flags &= ~VEXPORT;
820 if ((vp->flags & VSTRFIXED) == 0) {
821 if ((vp->flags & VTEXTFIXED) == 0)
836 * Find the appropriate entry in the hash table from the name.
840 hashvar(const char *p)
842 unsigned int hashval;
844 hashval = ((unsigned char) *p) << 4;
845 while (*p && *p != '=')
846 hashval += (unsigned char) *p++;
847 return &vartab[hashval % VTABSIZE];
853 * Returns true if the two strings specify the same varable. The first
854 * variable name is terminated by '='; the second may be terminated by
855 * either '=' or '\0'.
859 varequal(const char *p, const char *q)
865 if (*p == '=' && *(q - 1) == '\0')