auto import from //depot/cupcake/@135843
diff --git a/sh/var.c b/sh/var.c
new file mode 100644
index 0000000..a1f1689
--- /dev/null
+++ b/sh/var.c
@@ -0,0 +1,825 @@
+/*	$NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami Exp $	*/
+
+/*-
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Kenneth Almquist.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#)var.c	8.3 (Berkeley) 5/4/95";
+#else
+__RCSID("$NetBSD: var.c,v 1.36 2004/10/06 10:23:43 enami Exp $");
+#endif
+#endif /* not lint */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <paths.h>
+
+/*
+ * Shell variables.
+ */
+
+#include "shell.h"
+#include "output.h"
+#include "expand.h"
+#include "nodes.h"	/* for other headers */
+#include "eval.h"	/* defines cmdenviron */
+#include "exec.h"
+#include "syntax.h"
+#include "options.h"
+#include "var.h"
+#include "memalloc.h"
+#include "error.h"
+#include "mystring.h"
+#include "parser.h"
+#include "show.h"
+#ifndef SMALL
+#include "myhistedit.h"
+#endif
+
+#ifdef SMALL
+#define VTABSIZE 39
+#else
+#define VTABSIZE 517
+#endif
+
+
+struct varinit {
+	struct var *var;
+	int flags;
+	const char *text;
+	void (*func)(const char *);
+};
+
+
+#if ATTY
+struct var vatty;
+#endif
+#ifdef WITH_HISTORY
+struct var vhistsize;
+struct var vterm;
+#endif
+struct var vifs;
+struct var vmpath;
+struct var vpath;
+struct var vps1;
+struct var vps2;
+struct var vps4;
+struct var vvers;
+struct var voptind;
+
+const struct varinit varinit[] = {
+#if ATTY
+	{ &vatty,	VSTRFIXED|VTEXTFIXED|VUNSET,	"ATTY=",
+	  NULL },
+#endif
+#ifdef WITH_HISTORY
+	{ &vhistsize,	VSTRFIXED|VTEXTFIXED|VUNSET,	"HISTSIZE=",
+	  sethistsize },
+#endif
+	{ &vifs,	VSTRFIXED|VTEXTFIXED,		"IFS= \t\n",
+	  NULL },
+	{ &vmpath,	VSTRFIXED|VTEXTFIXED|VUNSET,	"MAILPATH=",
+	  NULL },
+	{ &vpath,	VSTRFIXED|VTEXTFIXED,		"PATH=" _PATH_DEFPATH,
+	  changepath },
+	/*
+	 * vps1 depends on uid
+	 */
+	{ &vps2,	VSTRFIXED|VTEXTFIXED,		"PS2=> ",
+	  NULL },
+	{ &vps4,	VSTRFIXED|VTEXTFIXED,		"PS4=+ ",
+	  NULL },
+#ifdef WITH_HISTORY
+	{ &vterm,	VSTRFIXED|VTEXTFIXED|VUNSET,	"TERM=",
+	  setterm },
+#endif
+	{ &voptind,	VSTRFIXED|VTEXTFIXED|VNOFUNC,	"OPTIND=1",
+	  getoptsreset },
+	{ NULL,	0,				NULL,
+	  NULL }
+};
+
+struct var *vartab[VTABSIZE];
+
+STATIC int strequal(const char *, const char *);
+STATIC struct var *find_var(const char *, struct var ***, int *);
+
+/*
+ * Initialize the varable symbol tables and import the environment
+ */
+
+#ifdef mkinit
+INCLUDE "var.h"
+MKINIT char **environ;
+INIT {
+	char **envp;
+
+	initvar();
+	for (envp = environ ; *envp ; envp++) {
+		if (strchr(*envp, '=')) {
+			setvareq(*envp, VEXPORT|VTEXTFIXED);
+		}
+	}
+}
+#endif
+
+
+/*
+ * This routine initializes the builtin variables.  It is called when the
+ * shell is initialized and again when a shell procedure is spawned.
+ */
+
+void
+initvar(void)
+{
+	const struct varinit *ip;
+	struct var *vp;
+	struct var **vpp;
+
+	for (ip = varinit ; (vp = ip->var) != NULL ; ip++) {
+		if (find_var(ip->text, &vpp, &vp->name_len) != NULL)
+			continue;
+		vp->next = *vpp;
+		*vpp = vp;
+		vp->text = strdup(ip->text);
+		vp->flags = ip->flags;
+		vp->func = ip->func;
+	}
+	/*
+	 * PS1 depends on uid
+	 */
+	if (find_var("PS1", &vpp, &vps1.name_len) == NULL) {
+		vps1.next = *vpp;
+		*vpp = &vps1;
+		vps1.text = strdup(geteuid() ? "PS1=$ " : "PS1=# ");
+		vps1.flags = VSTRFIXED|VTEXTFIXED;
+	}
+}
+
+/*
+ * Safe version of setvar, returns 1 on success 0 on failure.
+ */
+
+int
+setvarsafe(const char *name, const char *val, int flags)
+{
+	struct jmploc jmploc;
+	struct jmploc *volatile savehandler = handler;
+	int err = 0;
+#ifdef __GNUC__
+	(void) &err;
+#endif
+
+	if (setjmp(jmploc.loc))
+		err = 1;
+	else {
+		handler = &jmploc;
+		setvar(name, val, flags);
+	}
+	handler = savehandler;
+	return err;
+}
+
+/*
+ * Set the value of a variable.  The flags argument is ored with the
+ * flags of the variable.  If val is NULL, the variable is unset.
+ */
+
+void
+setvar(const char *name, const char *val, int flags)
+{
+	const char *p;
+	const char *q;
+	char *d;
+	int len;
+	int namelen;
+	char *nameeq;
+	int isbad;
+
+	isbad = 0;
+	p = name;
+	if (! is_name(*p))
+		isbad = 1;
+	p++;
+	for (;;) {
+		if (! is_in_name(*p)) {
+			if (*p == '\0' || *p == '=')
+				break;
+			isbad = 1;
+		}
+		p++;
+	}
+	namelen = p - name;
+	if (isbad)
+		error("%.*s: bad variable name", namelen, name);
+	len = namelen + 2;		/* 2 is space for '=' and '\0' */
+	if (val == NULL) {
+		flags |= VUNSET;
+	} else {
+		len += strlen(val);
+	}
+	d = nameeq = ckmalloc(len);
+	q = name;
+	while (--namelen >= 0)
+		*d++ = *q++;
+	*d++ = '=';
+	*d = '\0';
+	if (val)
+		scopy(val, d);
+	setvareq(nameeq, flags);
+}
+
+
+
+/*
+ * Same as setvar except that the variable and value are passed in
+ * the first argument as name=value.  Since the first argument will
+ * be actually stored in the table, it should not be a string that
+ * will go away.
+ */
+
+void
+setvareq(char *s, int flags)
+{
+	struct var *vp, **vpp;
+	int nlen;
+
+	if (aflag)
+		flags |= VEXPORT;
+	vp = find_var(s, &vpp, &nlen);
+	if (vp != NULL) {
+		if (vp->flags & VREADONLY)
+			error("%.*s: is read only", vp->name_len, s);
+		if (flags & VNOSET)
+			return;
+		INTOFF;
+
+		if (vp->func && (flags & VNOFUNC) == 0)
+			(*vp->func)(s + vp->name_len + 1);
+
+		if ((vp->flags & (VTEXTFIXED|VSTACK)) == 0)
+			ckfree(vp->text);
+
+		vp->flags &= ~(VTEXTFIXED|VSTACK|VUNSET);
+		vp->flags |= flags & ~VNOFUNC;
+		vp->text = s;
+
+		INTON;
+		return;
+	}
+	/* not found */
+	if (flags & VNOSET)
+		return;
+	vp = ckmalloc(sizeof (*vp));
+	vp->flags = flags & ~VNOFUNC;
+	vp->text = s;
+	vp->name_len = nlen;
+	vp->next = *vpp;
+	vp->func = NULL;
+	*vpp = vp;
+}
+
+
+
+/*
+ * Process a linked list of variable assignments.
+ */
+
+void
+listsetvar(struct strlist *list, int flags)
+{
+	struct strlist *lp;
+
+	INTOFF;
+	for (lp = list ; lp ; lp = lp->next) {
+		setvareq(savestr(lp->text), flags);
+	}
+	INTON;
+}
+
+void
+listmklocal(struct strlist *list, int flags)
+{
+	struct strlist *lp;
+
+	for (lp = list ; lp ; lp = lp->next)
+		mklocal(lp->text, flags);
+}
+
+
+/*
+ * Find the value of a variable.  Returns NULL if not set.
+ */
+
+char *
+lookupvar(const char *name)
+{
+	struct var *v;
+
+	v = find_var(name, NULL, NULL);
+	if (v == NULL || v->flags & VUNSET)
+		return NULL;
+	return v->text + v->name_len + 1;
+}
+
+
+
+/*
+ * Search the environment of a builtin command.  If the second argument
+ * is nonzero, return the value of a variable even if it hasn't been
+ * exported.
+ */
+
+char *
+bltinlookup(const char *name, int doall)
+{
+	struct strlist *sp;
+	struct var *v;
+
+	for (sp = cmdenviron ; sp ; sp = sp->next) {
+		if (strequal(sp->text, name))
+			return strchr(sp->text, '=') + 1;
+	}
+
+	v = find_var(name, NULL, NULL);
+
+	if (v == NULL || v->flags & VUNSET || (!doall && !(v->flags & VEXPORT)))
+		return NULL;
+	return v->text + v->name_len + 1;
+}
+
+
+
+/*
+ * Generate a list of exported variables.  This routine is used to construct
+ * the third argument to execve when executing a program.
+ */
+
+char **
+environment(void)
+{
+	int nenv;
+	struct var **vpp;
+	struct var *vp;
+	char **env;
+	char **ep;
+
+	nenv = 0;
+	for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
+		for (vp = *vpp ; vp ; vp = vp->next)
+			if (vp->flags & VEXPORT)
+				nenv++;
+	}
+	ep = env = stalloc((nenv + 1) * sizeof *env);
+	for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
+		for (vp = *vpp ; vp ; vp = vp->next)
+			if (vp->flags & VEXPORT)
+				*ep++ = vp->text;
+	}
+	*ep = NULL;
+	return env;
+}
+
+
+/*
+ * Called when a shell procedure is invoked to clear out nonexported
+ * variables.  It is also necessary to reallocate variables of with
+ * VSTACK set since these are currently allocated on the stack.
+ */
+
+#ifdef mkinit
+void shprocvar(void);
+
+SHELLPROC {
+	shprocvar();
+}
+#endif
+
+void
+shprocvar(void)
+{
+	struct var **vpp;
+	struct var *vp, **prev;
+
+	for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
+		for (prev = vpp ; (vp = *prev) != NULL ; ) {
+			if ((vp->flags & VEXPORT) == 0) {
+				*prev = vp->next;
+				if ((vp->flags & VTEXTFIXED) == 0)
+					ckfree(vp->text);
+				if ((vp->flags & VSTRFIXED) == 0)
+					ckfree(vp);
+			} else {
+				if (vp->flags & VSTACK) {
+					vp->text = savestr(vp->text);
+					vp->flags &=~ VSTACK;
+				}
+				prev = &vp->next;
+			}
+		}
+	}
+	initvar();
+}
+
+
+
+/*
+ * Command to list all variables which are set.  Currently this command
+ * is invoked from the set command when the set command is called without
+ * any variables.
+ */
+
+void
+print_quoted(const char *p)
+{
+	const char *q;
+
+	if (strcspn(p, "|&;<>()$`\\\"' \t\n*?[]#~=%") == strlen(p)) {
+		out1fmt("%s", p);
+		return;
+	}
+	while (*p) {
+		if (*p == '\'') {
+			out1fmt("\\'");
+			p++;
+			continue;
+		}
+		q = index(p, '\'');
+		if (!q) {
+			out1fmt("'%s'", p );
+			return;
+		}
+		out1fmt("'%.*s'", (int)(q - p), p );
+		p = q;
+	}
+}
+
+static int
+sort_var(const void *v_v1, const void *v_v2)
+{
+	const struct var * const *v1 = v_v1;
+	const struct var * const *v2 = v_v2;
+
+	/* XXX Will anyone notice we include the '=' of the shorter name? */
+	return strcmp((*v1)->text, (*v2)->text);
+}
+
+/*
+ * POSIX requires that 'set' (but not export or readonly) output the
+ * variables in lexicographic order - by the locale's collating order (sigh).
+ * Maybe we could keep them in an ordered balanced binary tree
+ * instead of hashed lists.
+ * For now just roll 'em through qsort for printing...
+ */
+
+int
+showvars(const char *name, int flag, int show_value)
+{
+	struct var **vpp;
+	struct var *vp;
+	const char *p;
+
+	static struct var **list;	/* static in case we are interrupted */
+	static int list_len;
+	int count = 0;
+
+	if (!list) {
+		list_len = 32;
+		list = ckmalloc(list_len * sizeof *list);
+	}
+
+	for (vpp = vartab ; vpp < vartab + VTABSIZE ; vpp++) {
+		for (vp = *vpp ; vp ; vp = vp->next) {
+			if (flag && !(vp->flags & flag))
+				continue;
+			if (vp->flags & VUNSET && !(show_value & 2))
+				continue;
+			if (count >= list_len) {
+				list = ckrealloc(list,
+					(list_len << 1) * sizeof *list);
+				list_len <<= 1;
+			}
+			list[count++] = vp;
+		}
+	}
+
+	qsort(list, count, sizeof *list, sort_var);
+
+	for (vpp = list; count--; vpp++) {
+		vp = *vpp;
+		if (name)
+			out1fmt("%s ", name);
+		for (p = vp->text ; *p != '=' ; p++)
+			out1c(*p);
+		if (!(vp->flags & VUNSET) && show_value) {
+			out1fmt("=");
+			print_quoted(++p);
+		}
+		out1c('\n');
+	}
+	return 0;
+}
+
+
+
+/*
+ * The export and readonly commands.
+ */
+
+int
+exportcmd(int argc, char **argv)
+{
+	struct var *vp;
+	char *name;
+	const char *p;
+	int flag = argv[0][0] == 'r'? VREADONLY : VEXPORT;
+	int pflag;
+
+	pflag = nextopt("p") == 'p' ? 3 : 0;
+	if (argc <= 1 || pflag) {
+		showvars( pflag ? argv[0] : 0, flag, pflag );
+		return 0;
+	}
+
+	while ((name = *argptr++) != NULL) {
+		if ((p = strchr(name, '=')) != NULL) {
+			p++;
+		} else {
+			vp = find_var(name, NULL, NULL);
+			if (vp != NULL) {
+				vp->flags |= flag;
+				continue;
+			}
+		}
+		setvar(name, p, flag);
+	}
+	return 0;
+}
+
+
+/*
+ * The "local" command.
+ */
+
+int
+localcmd(int argc, char **argv)
+{
+	char *name;
+
+	if (! in_function())
+		error("Not in a function");
+	while ((name = *argptr++) != NULL) {
+		mklocal(name, 0);
+	}
+	return 0;
+}
+
+
+/*
+ * Make a variable a local variable.  When a variable is made local, it's
+ * value and flags are saved in a localvar structure.  The saved values
+ * will be restored when the shell function returns.  We handle the name
+ * "-" as a special case.
+ */
+
+void
+mklocal(const char *name, int flags)
+{
+	struct localvar *lvp;
+	struct var **vpp;
+	struct var *vp;
+
+	INTOFF;
+	lvp = ckmalloc(sizeof (struct localvar));
+	if (name[0] == '-' && name[1] == '\0') {
+		char *p;
+		p = ckmalloc(sizeof_optlist);
+		lvp->text = memcpy(p, optlist, sizeof_optlist);
+		vp = NULL;
+	} else {
+		vp = find_var(name, &vpp, NULL);
+		if (vp == NULL) {
+			if (strchr(name, '='))
+				setvareq(savestr(name), VSTRFIXED|flags);
+			else
+				setvar(name, NULL, VSTRFIXED|flags);
+			vp = *vpp;	/* the new variable */
+			lvp->text = NULL;
+			lvp->flags = VUNSET;
+		} else {
+			lvp->text = vp->text;
+			lvp->flags = vp->flags;
+			vp->flags |= VSTRFIXED|VTEXTFIXED;
+			if (name[vp->name_len] == '=')
+				setvareq(savestr(name), flags);
+		}
+	}
+	lvp->vp = vp;
+	lvp->next = localvars;
+	localvars = lvp;
+	INTON;
+}
+
+
+/*
+ * Called after a function returns.
+ */
+
+void
+poplocalvars(void)
+{
+	struct localvar *lvp;
+	struct var *vp;
+
+	while ((lvp = localvars) != NULL) {
+		localvars = lvp->next;
+		vp = lvp->vp;
+		TRACE(("poplocalvar %s", vp ? vp->text : "-"));
+		if (vp == NULL) {	/* $- saved */
+			memcpy(optlist, lvp->text, sizeof_optlist);
+			ckfree(lvp->text);
+		} else if ((lvp->flags & (VUNSET|VSTRFIXED)) == VUNSET) {
+			(void)unsetvar(vp->text, 0);
+		} else {
+			if (vp->func && (vp->flags & VNOFUNC) == 0)
+				(*vp->func)(lvp->text + vp->name_len + 1);
+			if ((vp->flags & VTEXTFIXED) == 0)
+				ckfree(vp->text);
+			vp->flags = lvp->flags;
+			vp->text = lvp->text;
+		}
+		ckfree(lvp);
+	}
+}
+
+
+int
+setvarcmd(int argc, char **argv)
+{
+	if (argc <= 2)
+		return unsetcmd(argc, argv);
+	else if (argc == 3)
+		setvar(argv[1], argv[2], 0);
+	else
+		error("List assignment not implemented");
+	return 0;
+}
+
+
+/*
+ * The unset builtin command.  We unset the function before we unset the
+ * variable to allow a function to be unset when there is a readonly variable
+ * with the same name.
+ */
+
+int
+unsetcmd(int argc, char **argv)
+{
+	char **ap;
+	int i;
+	int flg_func = 0;
+	int flg_var = 0;
+	int ret = 0;
+
+	while ((i = nextopt("evf")) != '\0') {
+		if (i == 'f')
+			flg_func = 1;
+		else
+			flg_var = i;
+	}
+	if (flg_func == 0 && flg_var == 0)
+		flg_var = 1;
+
+	for (ap = argptr; *ap ; ap++) {
+		if (flg_func)
+			ret |= unsetfunc(*ap);
+		if (flg_var)
+			ret |= unsetvar(*ap, flg_var == 'e');
+	}
+	return ret;
+}
+
+
+/*
+ * Unset the specified variable.
+ */
+
+int
+unsetvar(const char *s, int unexport)
+{
+	struct var **vpp;
+	struct var *vp;
+
+	vp = find_var(s, &vpp, NULL);
+	if (vp == NULL)
+		return 1;
+
+	if (vp->flags & VREADONLY)
+		return (1);
+
+	INTOFF;
+	if (unexport) {
+		vp->flags &= ~VEXPORT;
+	} else {
+		if (vp->text[vp->name_len + 1] != '\0')
+			setvar(s, nullstr, 0);
+		vp->flags &= ~VEXPORT;
+		vp->flags |= VUNSET;
+		if ((vp->flags & VSTRFIXED) == 0) {
+			if ((vp->flags & VTEXTFIXED) == 0)
+				ckfree(vp->text);
+			*vpp = vp->next;
+			ckfree(vp);
+		}
+	}
+	INTON;
+	return 0;
+}
+
+
+/*
+ * Returns true if the two strings specify the same varable.  The first
+ * variable name is terminated by '='; the second may be terminated by
+ * either '=' or '\0'.
+ */
+
+STATIC int
+strequal(const char *p, const char *q)
+{
+	while (*p == *q++) {
+		if (*p++ == '=')
+			return 1;
+	}
+	if (*p == '=' && *(q - 1) == '\0')
+		return 1;
+	return 0;
+}
+
+/*
+ * Search for a variable.
+ * 'name' may be terminated by '=' or a NUL.
+ * vppp is set to the pointer to vp, or the list head if vp isn't found
+ * lenp is set to the number of charactets in 'name'
+ */
+
+STATIC struct var *
+find_var(const char *name, struct var ***vppp, int *lenp)
+{
+	unsigned int hashval;
+	int len;
+	struct var *vp, **vpp;
+	const char *p = name;
+
+	hashval = 0;
+	while (*p && *p != '=')
+		hashval = 2 * hashval + (unsigned char)*p++;
+	len = p - name;
+
+	if (lenp)
+		*lenp = len;
+	vpp = &vartab[hashval % VTABSIZE];
+	if (vppp)
+		*vppp = vpp;
+
+	for (vp = *vpp ; vp ; vpp = &vp->next, vp = *vpp) {
+		if (vp->name_len != len)
+			continue;
+		if (memcmp(vp->text, name, len) != 0)
+			continue;
+		if (vppp)
+			*vppp = vpp;
+		return vp;
+	}
+	return NULL;
+}