Google_Protobuf协议——protobuf代码中的通讯

た入场券 2022-06-02 02:48 678阅读 0赞

*  序列化和反序列化
 *  计算序列化后的长度
 *  代码实现
    
     *  定义发送与接收基类以及函数
     *  序列化到数组
     *  数组反序列化
     *  序列化到字符串
     *  字符串反序列化

在类google::protobuf::Message中有protobuf通讯的函数，将信息序列化和反序列化，在由proto文件生成的.cc和.h文件中，消息体生成由命名空间匡制，继承google::protobuf::Message的类。  
在生成的test.pb.h中

/* @@protoc_insertion_point(class_definition:zxtest.prototest.TestSend) */
    class TestSend : public ::google::protobuf::Message  {
     public:
      TestSend();
      virtual ~TestSend();
    
      TestSend(const TestSend& from);
    
      ...
     }

# 序列化和反序列化 #

序列化函数组

//序列化到编码流
    bool SerializeToCodedStream(io::CodedOutputStream* output) const;
    //序列化到字符串
    bool SerializeToString(string* output) const;
    //序列化为字符串
    string SerializeAsString() const;
    //序列化到数组
    bool SerializeToArray(void* data, int size) const;

反序列化数组

//编码流反序列化
    bool ParseFromCodedStream(io::CodedInputStream* input);
    //字符串反序列化
    bool ParseFromString(const string& data);
    //数组反序列化
    bool ParseFromArray(const void* data, int size);

# 计算序列化后的长度 #

int ByteSize() const {
        return internal::ToIntSize(ByteSizeLong());
    }

# 代码实现 #

## 定义发送与接收基类以及函数 ##

google::protobuf::Message buffmessage;
    
    protobufsend(google::protobuf::Message &buffmessage);
    protobufreceive(google::protobuf::Message &buffmessage);

## 序列化到数组 ##

int p_buffer_size = buffmessage.ByteSize();
        if (0 == p_buffer_size)
            throw std::string("ByteSize is zero!!!");
    
        char *p_buffer = new char[p_buffer_size];
        if (!p_buffer)
            throw std::string("new buffer is error!!!");
    
        if (!buffmessage.SerializeToArray(p_buffer, p_buffer_size))
        {
            delete p_buffer;
            p_buffer = nullptr;
            p_buffer_size = 0;
            throw std::string("SerializeToArray is error!!!");
        }

## 数组反序列化 ##

if (!buffmessage.ParseFromArray(p_buffer,p_buffer_size))
        {
            delete p_buffer;
            p_buffer = nullptr;
            p_buffer_size = 0;
            throw std::string("ParseFromArray is error!!!");
        }

## 序列化到字符串 ##

std::string strbuffer = buffmessage.SerializeAsString();
        if (strbuffer.empty())
        {
            throw std::string("SerializeAsString is error!!!");
        }

或

std::string strbuffer("");
        if (!buffmessage.SerializeToString(&strbuffer))
            throw std::string("SerializeToString is error!!!");

## 字符串反序列化 ##

if (!buffmessage.ParseFromString(strbuffer))
        {
            strbuffer.clear();
            throw std::string("ParseFromString is empty!!!");
        }