protobuf在unity 和 linux c++服务器的使用

unity使用protobuf-net见这里
https://blog.youkuaiyun.com/qq_35107322/article/details/110396018

服务器快速安装
1 yum install protobuf-devel
2 项目的make文件加入
-lprotobuf
3 编写proto文件
4 根据proto文件生成c代码
protoc game.proto --cpp_out=./
5 写代码

测试代码；

协议文件

[root@VM_156_144_centos socket_tcp]# vim game.proto 
syntax="proto2";

enum MSG_ID
{
    MSG_ID_CS_LOGIN_REQ = 1;
    MSG_ID_SC_LOGIN_RSP = 2;
}

message CS_LOGIN_REQ
{

}

message SC_LOGIN_RSP
{
    optional int32 ret = 1;
}

message MESSAGE_HEAD
{
    optional MSG_ID msg_id = 1;
    optional int64 user_id = 2;
}

message MESSAGE_BODY
{
    optional CS_LOGIN_REQ cs_login_req = 1;
    optional SC_LOGIN_RSP sc_login_rsp = 2;
}

message MESSAGE{
    optional MESSAGE_HEAD head = 1;
    optional MESSAGE_BODY body = 2;
}

unity中打包发送

public static void send_login_req()
    {
        Message msg = new Message();
        msg.Head = new MessageHead();
        msg.Body = new MessageBody();
        msg.Head.MsgId = MsgId.MsgIdCsLoginReq;
        msg.Head.UserId = 123;
        send_msg(msg);
    }
    public static void send_msg(Message msg)
    {
        MemoryStream ms = new MemoryStream();
        Serializer.Serialize<Message>(ms, msg);
        byte[] data = ms.ToArray();
        Debug.Log("send_msg: size: " + ms.Length.ToString());
        sendBuf(data);
    }
     public void sendBuf(byte[] buf)
    {
        Thread thrSend = new Thread(SendMessageByBuf);
        thrSend.Start(buf);
    }
    private void SendMessageByBuf(object obj)
    {
        byte[] buf = (byte[])obj;
        try
        {
            tcpClient.Client.Send(buf);
            
            print("发送完毕: " + " size: " + buf.Length.ToString());
        }
        catch
        {
            SocketClose();
        }
    }

服务器解包代码

using message_cb_fn_t = std::function<int(Session* session, MESSAGE_HEAD* head, MESSAGE_BODY* body)> ;

void GameMessageMgr::on_default_recv_msg(const char* buf, ssize_t nread){
    MESSAGE msg;
    bool succ = msg.ParseFromArray(buf, nread);
    if(succ)
    {   
        if(!msg.has_head())return;
        int64_t msgid = msg.head().msg_id();
        printf("on_default_recv_msg suc, msgid: %lld, userid: %lld\n", msgid, msg.head().user_id());
        message_cb_fn_t cb = get_message_cb(msgid);
        if(cb && msg.has_head() && msg.has_body()){
            cb(nullptr, &msg.head(), &msg.body());
        }   
    }   
    else{
        printf("on_default_recv_msg fail\n");
    }   
}

run:
on_default_recv_msg suc, msgid: 1, userid: 9190