Daemon using dbus to send messages seems to use lots of memory without release them.

[Croach]

2012/12/25 Croach <croach at gmail.com>:
> Hi,
>
> I have do porting dbus-1.6.4 to a embedded system, and I find that the
> memory of the daemon using dbus grows till the daemon runs out of the
> memory.
> I have put the following sample program to a function and run it for
> 10000 times with Valgrind.
>
> http://dbus.freedesktop.org/doc/dbus-tutorial.html#sample-program-1

I have updated the program we tested with Valgrind.
We use glib-2.28.8, dbus-glib-0.100.

#include <dbus/dbus.h>
#include <dbus/dbus-glib.h>
#include <stdlib.h>

int test()
{
	DBusGConnection *connection;
	GError *error;
	DBusGProxy *proxy;
	char **name_list;
	char **name_list_ptr;

	g_type_init ();

	error = NULL;
	connection = dbus_g_bus_get (DBUS_BUS_SESSION, &error);
	if (connection == NULL)
	{
		g_printerr ("Failed to open connection to bus: %s\n", error->message);
		g_error_free (error);
		exit (1);
	}

	/* Create a proxy object for the "bus driver" (name "org.freedesktop.DBus") */

	proxy = dbus_g_proxy_new_for_name (connection,
									   DBUS_SERVICE_DBUS,
									   DBUS_PATH_DBUS,
									   DBUS_INTERFACE_DBUS);

	/* Call ListNames method, wait for reply */
	error = NULL;
	if (!dbus_g_proxy_call (proxy, "ListNames", &error, G_TYPE_INVALID,
							G_TYPE_STRV, &name_list, G_TYPE_INVALID))
	{
		/* Just do demonstrate remote exceptions versus regular GError */
		if (error->domain == DBUS_GERROR && error->code ==
DBUS_GERROR_REMOTE_EXCEPTION)
			g_printerr ("Caught remote method exception %s: %s",
						dbus_g_error_get_name (error),
						error->message);
		else
			g_printerr ("Error: %s\n", error->message);
		g_error_free (error);
		exit (1);
	}

	/* Print the results */

	g_print ("Names on the message bus:\n");

	for (name_list_ptr = name_list; *name_list_ptr; name_list_ptr++)
	{
		g_print ("  %s\n", *name_list_ptr);
	}
	g_strfreev (name_list);

	g_type_class_ref(proxy);
	g_object_unref (proxy);
	proxy = NULL;
	name_list = NULL;

	return 0;
}

int main()
{
	int count = 10000;
	while (count -- > 0) {
		test();
	}
}
>
> The memory grows up and valgrind reports that "still reachable" with some bytes.
> I know that the meaning of "still reachable" is not memory leak, but
> the program uses lots of memory.
> So I would like to know what have I missed anything about running the
> sample program or should I use any function to release the memory
> after using g_object_unref()?
>
> Thanks for any help.
> Croach Chang