Bluez Simple Agent using DBUS

agent.c

/*
 * gcc `pkg-config --cflags glib-2.0 gio-2.0` -Wall -Wextra -o ./bin/agent ./agent.c `pkg-config --libs glib-2.0 gio-2.0`
 */
#include <glib.h>
#include <gio/gio.h>
#include <stdio.h>
#include "agent.h"

GMainLoop *loop;
GDBusConnection *con;
#define AGENT_PATH	"/org/bluez/AutoPinAgent"

static void bluez_agent_method_call(GDBusConnection *conn,
					const gchar *sender,
					const gchar *path,
					const gchar *interface,
					const gchar *method,
					GVariant *params,
					GDBusMethodInvocation *invocation,
					void *userdata)
{
	int pass;
	int entered;
	char *opath;
	GVariant *p= g_dbus_method_invocation_get_parameters(invocation);

	g_print("Agent method call: %s.%s()\n", interface, method);
	if(!strcmp(method, "RequestPinCode")) {
		;
	}
	else if(!strcmp(method, "DisplayPinCode")) {
		;
	}
	else if(!strcmp(method, "RequestPasskey")) {
		g_print("Getting the Pin from user: ");
		fscanf(stdin, "%d", &pass);
		g_print("\n");
		g_dbus_method_invocation_return_value(invocation, g_variant_new("(u)", pass));
	}
	else if(!strcmp(method, "DisplayPasskey")) {
		g_variant_get(params, "(ouq)", &opath, &pass, &entered);
		g_print("Path: %s Pass: %d Entered: %d\n", opath, pass, entered);
		g_dbus_method_invocation_return_value(invocation, NULL);
	}
	else if(!strcmp(method, "RequestConfirmation")) {
		g_variant_get(params, "(ou)", &opath, &pass);
		g_print("Path: %s Pass: %d\n", opath, pass);
		g_dbus_method_invocation_return_value(invocation, NULL);
	}
	else if(!strcmp(method, "RequestAuthorization")) {
		;
	}
	else if(!strcmp(method, "AuthorizeService")) {
		;
	}
	else if(!strcmp(method, "Cancel")) {
		;
	}
	else
		g_print("We should not come here, unknown method\n");
}

static const GDBusInterfaceVTable agent_method_table = {
	.method_call = bluez_agent_method_call,
};

int bluez_register_agent(GDBusConnection *con)
{
	GError *error = NULL;
	guint id = 0;
	GDBusNodeInfo *info = NULL;

	static const gchar bluez_agent_introspection_xml[] =
		"<node name='/org/bluez/SampleAgent'>"
		"	<interface name='org.bluez.Agent1'>"
		"		<method name='Release'>"
		"		</method>"
		"		<method name='RequestPinCode'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='s' name='pincode' direction='out' />"
		"		</method>"
		"		<method name='DisplayPinCode'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='s' name='pincode' direction='in' />"
		"		</method>"
		"		<method name='RequestPasskey'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='u' name='passkey' direction='out' />"
		"		</method>"
		"		<method name='DisplayPasskey'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='u' name='passkey' direction='in' />"
		"			<arg type='q' name='entered' direction='in' />"
		"		</method>"
		"		<method name='RequestConfirmation'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='u' name='passkey' direction='in' />"
		"		</method>"
		"		<method name='RequestAuthorization'>"
		"			<arg type='o' name='device' direction='in' />"
		"		</method>"
		"		<method name='AuthorizeService'>"
		"			<arg type='o' name='device' direction='in' />"
		"			<arg type='s' name='uuid' direction='in' />"
		"		</method>"
		"		<method name='Cancel'>"
		"		</method>"
		"	</interface>"
		"</node>";

	info = g_dbus_node_info_new_for_xml(bluez_agent_introspection_xml, &error);
	if(error) {
		g_printerr("Unable to create node: %s\n", error->message);
		g_clear_error(&error);
		return 0;
	}

	id = g_dbus_connection_register_object(con, 
			AGENT_PATH,
			info->interfaces[0],
			&agent_method_table,
			NULL, NULL, &error);
	g_dbus_node_info_unref(info);
	//g_dbus_connection_unregister_object(con, id);
	/* call register method in AgentManager1 interface */
	return id;
}

//#define AGENT_PATH "/org/bluez/AutoPinAgent"
static int bluez_agent_call_method(const gchar *method, GVariant *param)
{
	GVariant *result;
	GError *error = NULL;

	result = g_dbus_connection_call_sync(con,
			"org.bluez",
			"/org/bluez",
			"org.bluez.AgentManager1",
			method,
			param,
			NULL,
			G_DBUS_CALL_FLAGS_NONE,
			-1,
			NULL,
			&error);
	if(error != NULL) {
		g_print("Register %s: %s\n", AGENT_PATH, error->message);
		return 1;
	}

	g_variant_unref(result);
	return 0;
}

static int bluez_register_autopair_agent(const char *cap)
{
	int rc;

	rc = bluez_agent_call_method("RegisterAgent", g_variant_new("(os)", AGENT_PATH, cap));
	if(rc)
		return 1;

	rc = bluez_agent_call_method("RequestDefaultAgent", g_variant_new("(o)", AGENT_PATH));
	if(rc) {
		bluez_agent_call_method("UnregisterAgent", g_variant_new("(o)", AGENT_PATH));
		return 1;
	}

	return 0;
}


static void cleanup_handler(int signo)
{
	if (signo == SIGINT) {
		g_print("received SIGINT\n");
		g_main_loop_quit(loop);
	}
}

int main(int argc, char **argv)
{
	int id;
	int rc;

	if(argc < 2)
		return 1;

	if(signal(SIGINT, cleanup_handler) == SIG_ERR)
		g_print("can't catch SIGINT\n");

	con = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, NULL);
	if(con == NULL) {
		g_print("Not able to get connection to system bus\n");
		return 1;
	}

	con = g_bus_get_sync(G_BUS_TYPE_SYSTEM, NULL, NULL);
	if(con == NULL) {
		g_print("Not able to get connection to system bus\n");
		return 1;
	}

	loop = g_main_loop_new(NULL, FALSE);

	id = bluez_register_agent(con);
	if(id == 0)
		goto fail;

	rc = bluez_register_autopair_agent(argv[1]);
	if(rc) {
		g_print("Not able to register default autopair agent\n");
		goto fail;
	}

	g_main_loop_run(loop);

fail:
	g_dbus_connection_unregister_object(con, id);
	g_object_unref(con);
	return 0;
}

agent.h

#ifndef BLUEZ_AGENT_H
#define BLUEZ_AGENT_H

#include <glib.h>
#include <gio/gio.h>

int bluez_register_agent(GDBusConnection *con);

#endif