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#include <dbus/dbus-glib.h>
#include <stdio.h>
#include <stdlib.h>
static void lose (const char *fmt, ...) G_GNUC_NORETURN G_GNUC_PRINTF (1, 2);
static void lose_gerror (const char *prefix, GError *error) G_GNUC_NORETURN;
static void
lose (const char *str, ...)
{
va_list args;
va_start (args, str);
vfprintf (stderr, str, args);
fputc ('\n', stderr);
va_end (args);
exit (1);
}
static void
lose_gerror (const char *prefix, GError *error)
{
lose ("%s: %s", prefix, error->message);
}
static gboolean
emit_signal (gpointer arg)
{
DBusGProxy *proxy = arg;
dbus_g_proxy_call_no_reply (proxy, "emitHelloSignal", G_TYPE_INVALID);
return TRUE;
}
static void
hello_signal_handler (DBusGProxy *proxy, const char *hello_string, gpointer user_data)
{
printf ("Received signal and it says: %s\n", hello_string);
}
int
main (int argc, char **argv)
{
DBusGConnection *bus;
DBusGProxy *remote_object;
GError *error = NULL;
GMainLoop *mainloop;
g_type_init ();
mainloop = g_main_loop_new (NULL, FALSE);
bus = dbus_g_bus_get (DBUS_BUS_SESSION, &error);
if (!bus)
lose_gerror ("Couldn't connect to session bus", error);
/* We use _for_name_owner in order to track this particular service
* instance, which lets us receive signals.
*/
remote_object = dbus_g_proxy_new_for_name (bus,
"org.designfu.TestService",
"/org/designfu/TestService/object",
"org.designfu.TestService");
if (!remote_object)
lose_gerror ("Failed to get name owner", error);
/* IMPORTANT:
*
* Note because this signal's signature is VOID__STRING, we do not
* need to register a marshaller, since there is a builtin one.
* However for other signatures, you must generate a marshaller,
* then call dbus_g_object_register_marshaller. It would look like
* this:
*
* dbus_g_object_register_marshaller (g_cclosure_marshal_VOID__STRING, G_TYPE_NONE, G_TYPE_STRING, G_TYPE_INVALID);
*
*/
/* Tell DBus what the type signature of the signal callback is; this
* allows us to sanity-check incoming messages before invoking the
* callback. You need to do this once for each proxy you create,
* not every time you want to connect to the signal.
*/
dbus_g_proxy_add_signal (remote_object, "HelloSignal", G_TYPE_STRING, G_TYPE_INVALID);
/* Actually connect to the signal. Note you can call
* dbus_g_proxy_connect_signal multiple times for one invocation of
* dbus_g_proxy_add_signal.
*/
dbus_g_proxy_connect_signal (remote_object, "HelloSignal", G_CALLBACK (hello_signal_handler),
NULL, NULL);
g_timeout_add (2000, emit_signal, remote_object);
g_main_loop_run (mainloop);
exit (0);
}
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