Question

这就是我在做什么：

我有一个服务器应用程序（类似于TcpGenericServerApp）。它接受消息（订阅），并且不会立即答复。连接保持打开状态。发生某些事件时，它将向所有连接的客户端发送通知。

然后，客户端必须分析数据包内容。这是我的消息定义：

namespace inet;

enum PacketType
{
   SUBSCRIBE = 0;
   PUBLISH = 1;
};

// 
// Message class for event notification service based on TCP.
// 
class EventNotificationMsg extends FieldsChunk
{
    int type @enum(PacketType);
    string awesomeName;

}

到目前为止非常容易。问题是数据包大小为1000B。此数据包将被TCP分为两个部分。现在，我必须对这些数据包进行碎片整理，以将其转换为EventNotificationMessage。我怎么做？还是有一种更简便的方法来提取awesomeName而不必对数据包进行碎片整理。

更多背景信息：

我正在使用TcpAppBase
当我简单地尝试填充不完整的数据包时，出现以下错误：Returning an incomplete chunk is not allowed according to the flags: 4
我尝试使用this示例对它进行碎片整理，但它产生了另一个错误：Implicit chunk serialization is disabled to prevent unpredictable performance degradation (you may consider changing the Chunk::enableImplicitChunkSerialization flag or passing the PF_ALLOW_SERIALIZATION flag to peek)。我使用的代码如下。

void EventNotificationSubscriber::socketDataArrived(TcpSocket *socket, Packet *msg, bool urgent)
{

    int bytes = msg->getByteLength();
    bytesReceivedSinceReset += bytes;
    if (bytesReceivedSinceReset % expectedBytesResponse == 0) {
        // we received the last bits of a packet
        tempPacket->insertAtBack(msg->peekData());
        // the packet should be complete now
        const Ptr<const EventNotificationMsg> eventNotificationPacket = msg->peekAtFront<EventNotificationMsg>(b(-1), Chunk::PF_ALLOW_INCORRECT);
        std::string name = eventNotificationPacket->awesomeName();
        }
        // there is nothing more to do
        delete tempPacket;
        tempPacket = nullptr;
        bytesReceivedSinceReset = 0;
    } else {
        if (tempPacket == nullptr){
            tempPacket = new Packet("TempPacket");
        }
        // this is an incomplete packet
        tempPacket->insertAtBack(msg->peekData());
    }


    // do this last as this will delete the packet :O
    TcpAppBase::socketDataArrived(socket, msg, urgent);

}

类变量的定义：

Packet* tempPacket;
int bytesReceivedSinceReset;

对Tcp数据包进行碎片整理

0 个答案: