nih-dbus/dbus_util.c

/* libnih
 *
 * dbus_util.c - D-Bus utility functions
 *
 * Copyright © 2009 Scott James Remnant <scott@netsplit.com>.
 *
 * 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif /* HAVE_CONFIG_H */


#include <stdio.h>
#include <stdarg.h>
#include <string.h>

#include <nih/macros.h>
#include <nih/alloc.h>
#include <nih/logging.h>

#include "dbus_util.h"


/**
 * nih_dbus_path:
 * @parent: parent object for new string,
 * @root: root of path.
 *
 * Generates a D-Bus path suitable for object registration rooted at
 * @root with each of the further elements joined with "/" separators and
 * appended after non-permissible characters are removed.
 *
 * The final argument to this function must be NULL to signify the end
 * of elements.
 *
 * If @parent is not NULL, it should be a pointer to another object which
 * will be used as a parent for the returned string.  When all parents
 * of the returned string are freed, the returned string will also be
 * freed.
 *
 * Returns: newly allocated string or NULL if insufficient memory.
 **/
char *
nih_dbus_path (const void *parent,
	       const char *root,
	       ...)
{
	const char *arg, *ptr;
	char       *path;
	va_list     args;
	size_t      len;

	nih_assert (root != NULL);

	/* First work out how much space we'll need */
	len = strlen (root);

	va_start (args, root);
	for (arg = va_arg (args, const char *); arg != NULL;
	     arg = va_arg (args, const char *)) {
		len += 1;

		if (! *arg)
			len += 1;

		for (ptr = arg; *ptr != '\0'; ptr++) {
			if (   ((*ptr >= 'a') && (*ptr <= 'z'))
			    || ((*ptr >= 'A') && (*ptr <= 'Z'))
			    || ((*ptr >= '0') && (*ptr <= '9'))) {
				len += 1;
			} else {
				len += 3;
			}
		}
	}
	va_end (args);

	/* Now we can allocate it */
	path = nih_alloc (parent, len + 1);
	if (! path)
		return NULL;

	/* And copy the elements in */
	strcpy (path, root);
	len = strlen (root);

	va_start (args, root);
	for (arg = va_arg (args, const char *); arg != NULL;
	     arg = va_arg (args, const char *)) {
		path[len++] = '/';

		if (! *arg)
			path[len++] = '_';

		for (ptr = arg; *ptr != '\0'; ptr++) {
			if (   ((*ptr >= 'a') && (*ptr <= 'z'))
			    || ((*ptr >= 'A') && (*ptr <= 'Z'))
			    || ((*ptr >= '0') && (*ptr <= '9'))) {
				path[len++] = *ptr;
			} else {
				path[len++] = '_';

				sprintf (path + len, "%02x", *ptr);
				len += 2;
			}
		}
	}
	va_end (args);

	path[len] = '\0';

	return path;
}