/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
/*	  All Rights Reserved  	*/


/*
 * Copyright 2002 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

#include "rcv.h"
#include <locale.h>

/*
 * mailx -- a modified version of a University of California at Berkeley
 *	mail program
 *
 * Variable handling stuff.
 */

static struct var	*lookup(char name[]);

/*
 * Assign a value to a variable.
 */
void
assign(char name[], char value[])
{
	register struct var *vp;
	register int h;

	if (name[0]=='-')
		deassign(name+1);
	else if (name[0]=='n' && name[1]=='o')
		deassign(name+2);
	else {
		h = hash(name);
		vp = lookup(name);
		if (vp == NOVAR) {
			if ((vp = (struct var *)
			    calloc(sizeof (*vp), 1)) == NULL)
				panic("Out of memory");
			vp->v_name = vcopy(name);
			vp->v_link = variables[h];
			variables[h] = vp;
		} else
			vfree(vp->v_value);
		vp->v_value = vcopy(value);
		/*
		 * for efficiency, intercept certain assignments here
		 */
		if (strcmp(name, "prompt")==0)
			prompt = vp->v_value;
		else if (strcmp(name, "debug")==0)
			debug = 1;
		if (debug) fprintf(stderr, "assign(%s)=%s\n", vp->v_name, vp->v_value);
	}
}

int
deassign(register char *s)
{
	register struct var *vp, *vp2;
	register int h;

	if ((vp2 = lookup(s)) == NOVAR) {
		if (!sourcing) {
			printf(gettext("\"%s\": undefined variable\n"), s);
			return(1);
		}
		return(0);
	}
	if (debug) fprintf(stderr, "deassign(%s)\n", s);
	if (strcmp(s, "prompt")==0)
		prompt = NOSTR;
	else if (strcmp(s, "debug")==0)
		debug = 0;
	h = hash(s);
	if (vp2 == variables[h]) {
		variables[h] = variables[h]->v_link;
		vfree(vp2->v_name);
		vfree(vp2->v_value);
		free(vp2);
		return(0);
	}
	for (vp = variables[h]; vp->v_link != vp2; vp = vp->v_link)
		;
	vp->v_link = vp2->v_link;
	vfree(vp2->v_name);
	vfree(vp2->v_value);
	free(vp2);
	return(0);
}

/*
 * Free up a variable string.  We do not bother to allocate
 * strings whose value is "" since they are expected to be frequent.
 * Thus, we cannot free same!
 */
void
vfree(register char *cp)
{
	if (!equal(cp, ""))
		free(cp);
}

/*
 * Copy a variable value into permanent (ie, not collected after each
 * command) space.  Do not bother to alloc space for ""
 */

char *
vcopy(char str[])
{
	register char *top, *cp, *cp2;

	if (equal(str, ""))
		return("");
	if ((top = (char *)calloc(strlen(str)+1, 1)) == NULL)
		panic("Out of memory");
	cp = top;
	cp2 = str;
	while (*cp++ = *cp2++)
		;
	return(top);
}

/*
 * Get the value of a variable and return it.
 * Look in the environment if its not available locally.
 */

char *
value(char name[])
{
	register struct var *vp;
	register char *cp;

	if ((vp = lookup(name)) == NOVAR)
		cp = getenv(name);
	else
		cp = vp->v_value;
	if (debug) fprintf(stderr, "value(%s)=%s\n", name, (cp)?cp:"");
	return(cp);
}

/*
 * Locate a variable and return its variable
 * node.
 */

static struct var *
lookup(char name[])
{
	register struct var *vp;
	register int h;

	h = hash(name);
	for (vp = variables[h]; vp != NOVAR; vp = vp->v_link)
		if (equal(vp->v_name, name))
			return(vp);
	return(NOVAR);
}

/*
 * Locate a group name and return it.
 */

struct grouphead *
findgroup(char name[])
{
	register struct grouphead *gh;
	register int h;

	h = hash(name);
	for (gh = groups[h]; gh != NOGRP; gh = gh->g_link)
		if (equal(gh->g_name, name))
			return(gh);
	return(NOGRP);
}

/*
 * Print a group out on stdout
 */
void
printgroup(char name[])
{
	register struct grouphead *gh;
	register struct mgroup *gp;

	if ((gh = findgroup(name)) == NOGRP) {
		printf(gettext("\"%s\": not a group\n"), name);
		return;
	}
	printf("%s\t", gh->g_name);
	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
		printf(" %s", gp->ge_name);
	printf("\n");
}

/*
 * Hash the passed string and return an index into
 * the variable or group hash table.
 */

int
hash(char name[])
{
	register unsigned h;
	register char *cp;

	for (cp = name, h = 0; *cp; h = (h << 2) + *cp++)
		;
	return(h % HSHSIZE);
}