static void set_backend_state()

in pvcalls-back.c [1084:1147]

• 64 lines of code
• 20 McCabe index (conditional complexity)

static void set_backend_state(struct xenbus_device *dev,
			      enum xenbus_state state)
{
	while (dev->state != state) {
		switch (dev->state) {
		case XenbusStateClosed:
			switch (state) {
			case XenbusStateInitWait:
			case XenbusStateConnected:
				xenbus_switch_state(dev, XenbusStateInitWait);
				break;
			case XenbusStateClosing:
				xenbus_switch_state(dev, XenbusStateClosing);
				break;
			default:
				WARN_ON(1);
			}
			break;
		case XenbusStateInitWait:
		case XenbusStateInitialised:
			switch (state) {
			case XenbusStateConnected:
				if (backend_connect(dev))
					return;
				xenbus_switch_state(dev, XenbusStateConnected);
				break;
			case XenbusStateClosing:
			case XenbusStateClosed:
				xenbus_switch_state(dev, XenbusStateClosing);
				break;
			default:
				WARN_ON(1);
			}
			break;
		case XenbusStateConnected:
			switch (state) {
			case XenbusStateInitWait:
			case XenbusStateClosing:
			case XenbusStateClosed:
				down(&pvcalls_back_global.frontends_lock);
				backend_disconnect(dev);
				up(&pvcalls_back_global.frontends_lock);
				xenbus_switch_state(dev, XenbusStateClosing);
				break;
			default:
				WARN_ON(1);
			}
			break;
		case XenbusStateClosing:
			switch (state) {
			case XenbusStateInitWait:
			case XenbusStateConnected:
			case XenbusStateClosed:
				xenbus_switch_state(dev, XenbusStateClosed);
				break;
			default:
				WARN_ON(1);
			}
			break;
		default:
			WARN_ON(1);
		}
	}
}