Application of X_MACRO in architecture design

For example, if you want to design a message processing module in the code, the code should be as concise as possible and scalable. Might as well try the X_MACRO technique. 

/*
    设计一个消息处理的模块，收到消息调用对应的处理函数
*/

#include <stdio.h>

// 消息表定义，后续增加消息类型，只需在这里增加一行，并增加对应的处理函数即可
#define MACROS_TABLE              \
    X_MACROS(MSG1, msg1_process)  \
    X_MACROS(MSG2, msg2_process)  \
    X_MACROS(MSG3, msg3_process)  \

// 消息枚举定义
typedef enum {
    #define X_MACROS(a, b) a,
    MACROS_TABLE
    #undef X_MACROS
    MSG_MAX 
} MSG_TYPE;

// 消息类型字符串定义
const char *msg_str[] = {
    #define X_MACROS(a, b) #a,
    MACROS_TABLE
    #undef X_MACROS 
};

// 处理函数原型定义
typedef void (*func)(void *p);

static void msg1_process(void *p) {
    printf("%s\n", (char *)p);
}

static void msg2_process(void *p) {
    printf("%s\n",(char *)p);
}

static void msg3_process(void *p) {
    printf("%s\n",(char *)p);
}

// 后续在上面添加处理函数

// 处理函数表
const func func_table[] = {
    #define X_MACROS(a, b) b,
    MACROS_TABLE
    #undef X_MACROS 
};

static void msg_handle(MSG_TYPE msg) {
    if (msg < MSG_MAX) {
        func_table[msg]((void *)msg_str[msg]);
    }
}

int main() {
    msg_handle(MSG1);
    msg_handle(MSG2);
    msg_handle(MSG3);
    return 0;
}