创建 WSM 固有消息

Question

我想创建一个名为 wsm_info 的新消息类型。

在这个消息类型中，我想包含一个车辆结构，如下：

struct vehicle{
   int vehicle_id;
   Coord vehicle_pos;
   float speed;
};

在静脉示例中，有一个名为 prepareWSM 的函数，它在 BaseWaveApplLayer.h 中声明。这个函数是virtual WaveShortMessage*类型的。

如果 wsm_info 是 WaveShortMessage 固有的，我就不需要为 wsm_info 编写和声明一个新的 prepareWSM，对吗？

那么如何使 WaveShortMessage 固有的 wsm_info 消息呢？

我试过在wsm_info.h中这样写：

class wsm_info : public WaveShortMessage

而不是之前写的：

class wsm_info : public ::omnetpp::cPacket

但我得到的错误是以下错误：

cannot initialize a variable of type wsm_info * with an rvalue of type WaveShortMessage

我的msg_info的完整代码如下：

cplusplus {{
#include "veins/base/utils/Coord.h"
#include "veins/modules/messages/WaveShortMessage_m.h"
}}

class noncobject Coord;

class WaveShortMessage;

struct vehicle {
        int vehicle_id;
        Coord vehicle_pos;
        float speed;
    };

message wsm_info extends WaveShortMessage {
    //Version of the Wave Short Message
    int wsmVersion = 0;
    //Determine which security mechanism was used
    int securityType = 0;
    //Channel Number on which this packet was sent
    int channelNumber;
    //Data rate with which this packet was sent
    int dataRate = 1;
    //Power Level with which this packet was sent
    int priority = 3;
    //Unique number to identify the service
    int psid = 0;
    //Provider Service Context
    string psc = "Service with some Data";
    //Length of Wave Short Message
    int wsmLength;

    vehicle data;

    int senderAddress = 0;
    int recipientAddress = -1;
    int serial = 0;
    Coord senderPos;
    simtime_t timestamp = 0;
}

任何人都可以看一下我的代码并指出错误的地方和原因吗？谢谢！

Answer 1

如果我没看错，你想延长 wsm_info.msg，对吗？

根据问题，您可以按以下方式修改您的wsm_info.msg：

cplusplus {{
#include "veins/modules/messages/WaveShortMessage_m.h"
}}

class WaveShortMessage;

message wsm_info extends WaveShortMessage {
   int vehicle_id;
   Coord vehicle_pos;
   float speed;
}

Answer 2

msg_info.msg应该有以下内容：

cplusplus {{
#include "veins/modules/messages/WaveShortMessage_m.h"
}}

class noncobject Coord;

struct vehicle {
   int vehicle_id;
   Coord vehicle_pos;
   float speed;
};

class WaveShortMessage;

packet wsm_info extends WaveShortMessage {
    vehicle data;
}

您不能使用 prepareWSM()，因为它会创建一个无法转换为 wsm_info 的 WaveShortMessage 对象。相反，您可以编写一个新方法，例如：

在/veins/src/veins/modules/application/ieee80211p/BaseWaveApplLayer.h中添加：

#include "veins/modules/messages/wsm_info_m.h"

并在 class 中添加声明：

wsm_info* prepare_wsm_info(std::string name, int dataLengthBits, t_channel channel, int priority, int rcvId, int serial=0);

在/veins/src/veins/modules/application/ieee80211p/BaseWaveApplLayer.cc中添加：

wsm_info*  BaseWaveApplLayer::prepare_wsm_info(std::string name, int lengthBits, t_channel channel, int priority, int rcvId, int serial) {
wsm_info* wsm = new wsm_info(name.c_str());
// ... content similar to prepareWSM()
}

为了设置vehicle结构你可以这样写：

wsm_info* info = prepare_wsm_info(/* parameters */);
vehicle veh;
veh.speed = 60;
veh.vehicle_id = 3;
// ...

info->setData(veh);

或者，您可以在 prepare_wsm_info() 的定义中为 vehicle 添加参数。

Answer 3

必须在哪里声明wsm_info.msg？在哪个文件夹中？

创建 WSM 固有消息

Create a WSM inherented message

omnet++

veins