core: Add kdbus helper functions for bus creation and lookup

src/kdbus.c

@@ -0,0 +1,125 @@
+/*
+ *
+ *  Wireless daemon for Linux
+ *
+ *  Copyright (C) 2013-2014  Intel Corporation. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; 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
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <glob.h>
+#include <ell/ell.h>
+
+#include "linux/kdbus.h"
+#include "src/kdbus.h"
+
+static int kdbus_control = -1;
+
+bool kdbus_create_bus(void)
+{
+	struct {
+		struct kdbus_cmd_make head;
+		/* bloom size item */
+		uint64_t bloom_size;
+		uint64_t bloom_type;
+		struct kdbus_bloom_parameter bloom_param;
+		/* name item */
+		uint64_t name_size;
+		uint64_t name_type;
+		char name_param[64];
+	} bus_make;
+
+	if (kdbus_control >= 0)
+		return false;
+
+	l_debug("Opening /dev/kdbus/control");
+
+	kdbus_control = open("/dev/kdbus/control", O_RDWR | O_CLOEXEC);
+	if (kdbus_control < 0) {
+		l_error("Failed to open kdbus control interface: %m");
+		return false;
+	}
+
+	memset(&bus_make, 0, sizeof(bus_make));
+	/* bloom size item */
+	bus_make.bloom_size = 16 + sizeof(bus_make.bloom_param);
+	bus_make.bloom_type = KDBUS_ITEM_BLOOM_PARAMETER;
+	bus_make.bloom_param.size = 64;
+	bus_make.bloom_param.n_hash = 1;
+	/* name item */
+	snprintf(bus_make.name_param, sizeof(bus_make.name_param),
+							"%u-iwd", getuid());
+	bus_make.name_size = 16 + strlen(bus_make.name_param) + 1;
+	bus_make.name_type = KDBUS_ITEM_MAKE_NAME;
+
+	bus_make.head.size = sizeof(bus_make.head) +
+				bus_make.bloom_size + bus_make.name_size;
+	bus_make.head.flags = KDBUS_MAKE_ACCESS_WORLD;
+
+	l_debug("Creating bus %s", bus_make.name_param);
+
+	if (ioctl(kdbus_control, KDBUS_CMD_BUS_MAKE, &bus_make) < 0) {
+		l_error("Failed to create bus: %m");
+		close(kdbus_control);
+		kdbus_control = -1;
+		return false;
+        }
+
+	return true;
+}
+
+bool kdbus_destroy_bus(void)
+{
+	if (kdbus_control < 0)
+		return false;
+
+	l_debug("Closing kdbus control interface");
+
+	close(kdbus_control);
+	kdbus_control = -1;
+
+	return true;
+}
+
+char *kdbus_lookup_bus(void)
+{
+	glob_t gl;
+	size_t i;
+	char *path = NULL;
+
+	if (glob("/dev/kdbus/*-iwd/bus", GLOB_ONLYDIR, NULL, &gl)) {
+		l_error("Failed to lookup bus directory");
+		return NULL;
+	}
+
+	if (gl.gl_pathc < 1) {
+		l_error("Failed to lookup bus endpoint");
+		return NULL;
+	}
+
+	path = l_strdup(gl.gl_pathv[0]);
+
+	globfree(&gl);
+
+	return path;
+}

src/kdbus.h

@@ -0,0 +1,28 @@
+/*
+ *
+ *  Wireless daemon for Linux
+ *
+ *  Copyright (C) 2013-2014  Intel Corporation. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <stdbool.h>
+
+bool kdbus_create_bus(void);
+bool kdbus_destroy_bus(void);
+
+char *kdbus_lookup_bus(void);