// b->服务端
#include <stdio.h>
#include <string.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h>

int main(int argc, char const *argv[])
{
    int b_fd = socket(AF_INET, SOCK_DGRAM, 0);
    if (b_fd < 0)
    {
        perror("socket");
        return 1;
    }

    struct sockaddr_in addr;
    bzero(&addr, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = htons(8000);
    addr.sin_addr.s_addr = htonl(INADDR_ANY); // 接收所有本地ip下同一网段的客户端消息
    // addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    bind(b_fd, (struct sockaddr *)&addr, sizeof(addr));

    while (1)
    {
        struct sockaddr_in src_addr;
        bzero(&src_addr, sizeof(src_addr));
        socklen_t src_addr_len = sizeof(src_addr);
        int n;
        socklen_t addr_len = sizeof(addr);
        recvfrom(b_fd, &n, sizeof(n), 0, (struct sockaddr *)&src_addr, &src_addr_len);
        printf("%d", n);

        char sendbuf[128] = "";

        if (n == 1)
            strcpy(sendbuf, "disen666");
        else if (n == 2)
            strcpy(sendbuf, "jack good");
        else if (n == 3)
            strcpy(sendbuf, "disen888");
        else if (n == 4)
            strcpy(sendbuf, "bye");

        sendto(b_fd, sendbuf, strlen(sendbuf), 0, (struct sockaddr *)&src_addr, src_addr_len);
    }

    close(b_fd);

    return 0;
}