static int vbg_set_session_capabilities()

in vboxguest/vboxguest_core.c [825:866]

• 31 lines of code
• 5 McCabe index (conditional complexity)

static int vbg_set_session_capabilities(struct vbg_dev *gdev,
					struct vbg_session *session,
					u32 or_mask, u32 not_mask,
					bool session_termination)
{
	u32 changed, previous;
	int ret = 0;

	mutex_lock(&gdev->session_mutex);

	if (gdev->acquire_mode_guest_caps & or_mask) {
		vbg_err("%s error: cannot set caps which are in acquire_mode\n",
			__func__);
		ret = -EBUSY;
		goto out;
	}

	/* Apply the changes to the session mask. */
	previous = session->set_guest_caps;
	session->set_guest_caps |= or_mask;
	session->set_guest_caps &= ~not_mask;

	/* If anything actually changed, update the global usage counters. */
	changed = previous ^ session->set_guest_caps;
	if (!changed)
		goto out;

	vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed, previous);

	ret = vbg_set_host_capabilities(gdev, session, session_termination);
	/* Roll back on failure, unless it's session termination time. */
	if (ret < 0 && !session_termination) {
		vbg_track_bit_usage(&gdev->set_guest_caps_tracker, changed,
				    session->set_guest_caps);
		session->set_guest_caps = previous;
	}

out:
	mutex_unlock(&gdev->session_mutex);

	return ret;
}