Report the actual error when read() or write() a network device failed.

This enable to actually detect and handle device removal (USB...).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37897 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/network/devices/ethernet/ethernet.cpp

@@ -278,7 +278,7 @@ ethernet_send_data(net_device *_device, net_buffer *buffer)
 		device->stats.send.errors++;
 		if (allocated)
 			gBufferModule->free(allocated);
-		return bytesWritten;
+		return errno;
 	}
 
 	device->stats.send.packets++;
@@ -323,7 +323,7 @@ ethernet_receive_data(net_device *_device, net_buffer **_buffer)
 	bytesRead = read(device->fd, data, device->frame_size);
 	if (bytesRead < 0) {
 		device->stats.receive.errors++;
-		status = bytesRead;
+		status = errno;
 		goto err;
 	}
 //dump_block((const char *)data, bytesRead, "rcv: ");

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

@@ -66,6 +66,8 @@ device_reader_thread(void* _interface)
 			}
 
 			fifo_enqueue_buffer(&interface->receive_queue, buffer);
+		} else if (status == B_DEVICE_NOT_FOUND) {
+				device_removed(device);
 		} else {
 			// In case of error, give the other threads some
 			// time to run since this is a high priority time thread.