Prepared net_device_monitor to accept device removal events.

- Introduced public net_device_monitor.
 - Changed the link protocol to maintain a lock per instance instead of inside the FIFO. Now all of the link instance data is protected.
 - Adapted the link protocol to use net_device_monitor.
 - Introduced a private Fifo class which doesn't maintain it's own lock.
  - Maybe we should add something like a public net_protocol_implementation which maintains a fifo and a benaphore? With the fifo using the structure's lock instead of maintaining it's own.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20614 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/network/stack/interfaces.cpp

@@ -593,9 +593,11 @@ unregister_device_handler(struct net_device *device, int32 type)
 
 
 status_t
-register_device_monitor(struct net_device *device,
-	net_receive_func receiveFunc, void *cookie)
+register_device_monitor(net_device *device, net_device_monitor *monitor)
 {
+	if (monitor->receive == NULL || monitor->event == NULL)
+		return B_BAD_VALUE;
+
 	BenaphoreLocker locker(sInterfaceLock);
 
 	// find device interface for this device
@@ -604,23 +606,13 @@ register_device_monitor(struct net_device *device,
 		return ENODEV;
 
 	BenaphoreLocker _(interface->rx_lock);
-
-	// Add new monitor
-
-	net_device_monitor *monitor = new (std::nothrow) net_device_monitor;
-	if (monitor == NULL)
-		return B_NO_MEMORY;
-
-	monitor->func = receiveFunc;
-	monitor->cookie = cookie;
 	interface->monitor_funcs.Add(monitor);
 	return B_OK;
 }
 
 
 status_t
-unregister_device_monitor(struct net_device *device,
-	net_receive_func receiveFunc, void *cookie)
+unregister_device_monitor(net_device *device, net_device_monitor *monitor)
 {
 	BenaphoreLocker locker(sInterfaceLock);
 
@@ -635,12 +627,8 @@ unregister_device_monitor(struct net_device *device,
 
 	DeviceMonitorList::Iterator iterator = interface->monitor_funcs.GetIterator();
 	while (iterator.HasNext()) {
-		net_device_monitor *monitor = iterator.Next();
-
-		if (monitor->cookie == cookie && monitor->func == receiveFunc) {
-			// found it
+		if (iterator.Next() == monitor) {
 			iterator.Remove();
-			delete monitor;
 			return B_OK;
 		}
 	}