tools: add ipc dbus example

1 files changed, 76 insertions, 0 deletions

diff --git a/schulung_tools/ipc_dbus/ping-server.c b/schulung_tools/ipc_dbus/ping-server.c
new file mode 100644
index 0000000..78e53c5
--- /dev/null
+++ b/schulung_tools/ipc_dbus/ping-server.c
@@ -0,0 +1,76 @@
+#include <dbus/dbus.h>
+#include <dbus/dbus-glib.h>
+#include <dbus/dbus-glib-lowlevel.h>
+#include <time.h>
+#include <string.h>
+
+static DBusHandlerResult signal_filter(DBusConnection *connection,
+				       DBusMessage *message, void *user_data)
+{
+	/* User data is the event loop we are running in */
+	GMainLoop *loop = user_data;
+
+	/* A signal from the bus saying we are about to be disconnected */
+	if (dbus_message_is_signal(message, "org.freedesktop.Local",
+				   "Disconnected")) {
+		/* Tell the main loop to quit */
+		g_main_loop_quit (loop);
+		/* We have handled this message, don't pass it on */
+		return DBUS_HANDLER_RESULT_HANDLED;
+
+	} else if (dbus_message_is_signal(message, "de.linutronix.Ping",
+					  "Ping")) {
+		struct timespec rx_time;
+		DBusError error;
+		char *s;
+
+		clock_gettime(CLOCK_MONOTONIC, &rx_time);
+
+		dbus_error_init(&error);
+
+		if (dbus_message_get_args(message, &error, DBUS_TYPE_STRING,
+					  &s, DBUS_TYPE_INVALID)) {
+			g_print("%ld.%06ld: ping received: %d bytes\n",
+				rx_time.tv_sec, rx_time.tv_nsec / 1000,
+				strlen(s) + 1);
+		} else {
+			g_print("%ld.%06ld: ping received, but error"
+				" getting message: %s\n",
+				rx_time.tv_sec, rx_time.tv_nsec / 1000,
+				error.message);
+			dbus_error_free(&error);
+		}
+
+		return DBUS_HANDLER_RESULT_HANDLED;
+	}
+
+	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+int main(int argc, char *argv[])
+{
+	GMainLoop *loop;
+	DBusConnection *bus;
+	DBusError error;
+
+	loop = g_main_loop_new(NULL, FALSE);
+	dbus_error_init(&error);
+	bus = dbus_bus_get(DBUS_BUS_SESSION, &error);
+
+	if (!bus) {
+		g_warning("Failed to connect to the D-BUS daemon: %s",
+			  error.message);
+		dbus_error_free (&error);
+		return 1;
+	}
+
+	dbus_connection_setup_with_g_main (bus, NULL);
+	/* listening to messages from all objects as no path is specified */
+	dbus_bus_add_match(bus,
+			   "type='signal',interface='de.linutronix.Ping'",
+			   &error);
+	dbus_connection_add_filter(bus, signal_filter, loop, NULL);
+	g_main_loop_run (loop);
+
+	return 0;
+}