/* $Id$
 * UDP Gateway persistent configuration pathname detection
 * Copyright (C) 2005 Jan Kratochvil <project-udpgate@jankratochvil.net>
 * 
 * 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; exactly version 2 of June 1991 is required
 * 
 * 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  02111-1307  USA
 */


#include "config.h"

#include <glib/gmessages.h>
#include <glib/gmem.h>
#include <glib/gstrfuncs.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>

#include "configuration-pathname.h"	/* self */


/* OK, GConf would be nice.
 * Unfortunately the fully-static build does not support GConf process spawn at
 * all. Also /etc/sysconfig directory is standard for the daemon services.
 */


static const gchar *static_pathname;
static gboolean verbose=FALSE;


static gboolean try_pairname(const gchar *dirname,const gchar *filename)
{
gchar *pathname;

	g_return_val_if_fail(dirname!=NULL,FALSE);
	g_return_val_if_fail(filename!=NULL,FALSE);

	if (static_pathname)
		return FALSE;
	if (access(dirname,W_OK|X_OK)) {
		if (verbose)
			g_warning(_("Configuration directory not accessible(X) and/or writable(W): %s"),dirname);
		return FALSE;
		}
	pathname=g_strdup_printf("%s/%s",dirname,filename);
	if (access(pathname,R_OK|W_OK) && errno!=ENOENT) {
		if (verbose)
			g_warning(_("Configuration pathname not readable(R) and/or writable(W): %s"),pathname);
		g_free(pathname);
		return FALSE;
		}
	static_pathname=pathname;
	return TRUE;
}

G_CONST_RETURN gchar *configuration_pathname(void)
{
const gchar *home_val;
static gboolean first=TRUE;

	if (!static_pathname && first) {
		try_pairname(G_STRINGIFY(SYSCONFDIR) "/sysconfig",PACKAGE);
		try_pairname(G_STRINGIFY(SYSCONFDIR) "/default",PACKAGE);
		try_pairname(G_STRINGIFY(SYSCONFDIR) "",PACKAGE);
		if ((home_val=getenv("HOME")))
			try_pairname(home_val,"." PACKAGE "rc");
		if (!static_pathname && !verbose) {
			verbose=TRUE;
			configuration_pathname();
			g_warning(_("All automatic configuration pathnames failed; configuration persistency disabled."));
			}
		first=FALSE;
		}
	return static_pathname;
}