#ifndef lint
static const char	RCSid[] = "$Id: expandarg.c,v 2.4 2003/02/22 02:07:22 greg Exp $";
#endif
/*
 * Get additional command arguments from file or environment.
 *
 *  External symbols declared in standard.h
 */

/* ====================================================================
 * The Radiance Software License, Version 1.0
 *
 * Copyright (c) 1990 - 2002 The Regents of the University of California,
 * through Lawrence Berkeley National Laboratory.   All rights reserved.
 *
 * 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. The end-user documentation included with the redistribution,
 *           if any, must include the following acknowledgment:
 *             "This product includes Radiance software
 *                 (http://radsite.lbl.gov/)
 *                 developed by the Lawrence Berkeley National Laboratory
 *               (http://www.lbl.gov/)."
 *       Alternately, this acknowledgment may appear in the software itself,
 *       if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Radiance," "Lawrence Berkeley National Laboratory"
 *       and "The Regents of the University of California" must
 *       not be used to endorse or promote products derived from this
 *       software without prior written permission. For written
 *       permission, please contact radiance@radsite.lbl.gov.
 *
 * 5. Products derived from this software may not be called "Radiance",
 *       nor may "Radiance" appear in their name, without prior written
 *       permission of Lawrence Berkeley National Laboratory.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 Lawrence Berkeley National Laboratory OR
 * ITS 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Lawrence Berkeley National Laboratory.   For more
 * information on Lawrence Berkeley National Laboratory, please see
 * <http://www.lbl.gov/>.
 */

#include "standard.h"

#define MAXARGEXP	512		/* maximum argument expansion */

			/* set the following to suit, -1 to disable */
int	envexpchr = '$';		/* environment expansion character */
int	filexpchr = '@';		/* file expansion character */


int
expandarg(acp, avp, n)		/* expand list at argument n */
int	*acp;
register char	***avp;
int	n;
{
	int	ace;
	char	*ave[MAXARGEXP];
	char	**newav;
					/* check argument */
	if (n >= *acp)
		return(0);
	errno = 0;	
	if ((*avp)[n][0] == filexpchr) {		/* file name */
		ace = wordfile(ave, (*avp)[n]+1);
		if (ace < 0)
			return(-1);	/* no such file */
	} else if ((*avp)[n][0] == envexpchr) {		/* env. variable */
		ace = wordstring(ave, getenv((*avp)[n]+1));
		if (ace < 0)
			return(-1);	/* no such variable */
	} else						/* regular argument */
		return(0);
					/* allocate new pointer list */
	newav = (char **)bmalloc((*acp+ace)*sizeof(char *));
	if (newav == NULL)
		return(-1);
					/* copy preceeding arguments */
	bcopy((char *)*avp, (char *)newav, n*sizeof(char *));
					/* copy expanded argument */
	bcopy((char *)ave, (char *)(newav+n), ace*sizeof(char *));
					/* copy trailing arguments + NULL */
	bcopy((char *)(*avp+n+1), (char *)(newav+n+ace), (*acp-n)*sizeof(char *));
					/* free old list */
	bfree((char *)*avp, (*acp+1)*sizeof(char *));
					/* assign new list */
	*acp += ace-1;
	*avp = newav;
	return(1);			/* return success */
}