/*
 *	aegis - project change supervisor
 *	Copyright (C) 1995, 1999, 2003 Peter Miller;
 *	All rights reserved.
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This program is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *	GNU General Public License for more details.
 *
 *	You should have received a copy of the GNU General Public License
 *	along with this program; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 * MANIFEST: functions to manipulate the program name
 */

#include <ac/string.h>

#include <exeext.h>
#include <progname.h>


static const char *progname;


void
progname_set(char *s)
{
    /*
     * do NOT put tracing in this function
     * do NOT put asserts in this function
     *	they both depend on progname, which is not yet set
     */
    for (;;)
    {
	char *slash = strrchr(s, '/');

	/*
	 * we were invoked as
	 *	progname -args
	 */
	if (!slash)
	{
	    /*
	     * Nuke any ugly progname suffix
	     * if it has one.
	     */
	    int n = exeext(s);
	    if (n > 0)
		s[n] = 0;
	    progname = s;
	    break;
	}

	/*
	 * we were invoked as
	 *	/usr/local/progname -args
	 */
	if (slash[1])
	{
	    progname = slash + 1;
	    break;
	}

	/*
	 * this is real nasty:
	 * it is possible to invoke us as
	 *	/usr//local///bin////progname///// -args
	 * and it is legal!!
	 */
	*slash = 0;
    }
}


const char *
progname_get(void)
{
    /* do NOT put tracing in this function */
    return (progname ? progname : "");
}
