C++结构体与C语言兼容性 跨语言交互设计

struct

extern "C"

extern "C"

int

char

char

#pragma pack(n)

__attribute__((packed))

extern "C"

void*

void*

extern "C"

#ifdef __cplusplus

extern "C"

extern "C"

// my_interface.h
#ifndef MY_INTERFACE_H
#define MY_INTERFACE_H

#ifdef __cplusplus
extern "C" {
#endif

// 确保结构体是POD，并考虑对齐
#pragma pack(push, 1) // 强制1字节对齐，或者根据需求设置
typedef struct MyData_C {
    int id;
    float value;
    char name[32];
} MyData_C;
#pragma pack(pop)

// C风格的API函数，用于C++内部复杂逻辑的封装
// 返回一个不透明的句柄
void* create_my_object(int initial_id);
// 通过句柄操作对象
void set_my_object_value(void* obj_handle, float new_value);
float get_my_object_value(void* obj_handle);
// 释放对象
void destroy_my_object(void* obj_handle);

#ifdef __cplusplus
} // extern "C"
#endif

#endif // MY_INTERFACE_H

// my_interface.cpp (C++实现)
#include "my_interface.h"
#include <iostream>
#include <string>
#include <memory> // For std::unique_ptr if desired

// C++内部的复杂类
class MyComplexObject {
public:
    MyComplexObject(int id) : m_id(id), m_value(0.0f) {
        std::cout << "MyComplexObject created with ID: " << m_id << std::endl;
    }
    ~MyComplexObject() {
        std::cout << "MyComplexObject destroyed with ID: " << m_id << std::endl;
    }

    void setValue(float val) { m