w5500ping命令程序

以下是使用W5500芯片实现ping命令程序的示例代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "w5500.h"

#define IP_ADDR {192,168,1,1}   // 目标IP地址
#define PING_COUNT 4            // ping测试次数
#define PING_TIMEOUT 3000       // ping超时时间，单位为毫秒

#define ICMP_HEADER_SIZE 8      // ICMP报文头部大小
#define ICMP_ECHO_REQUEST 8     // ICMP回显请求类型
#define ICMP_ECHO_REPLY 0       // ICMP回显应答类型

#define ICMP_SEQ_NUMBER 0x1234  // ICMP报文序号

// ICMP报文结构体
typedef struct {
    uint8_t type;               // 报文类型
    uint8_t code;               // 报文代码
    uint16_t checksum;          // 报文校验和
    uint16_t identifier;        // 报文标识符
    uint16_t sequence_number;   // 报文序号
    uint8_t data[1];            // 报文数据
} icmp_packet_t;

// 计算ICMP报文校验和
uint16_t checksum(void *buf, int len) {
    uint16_t *data = buf;
    uint32_t sum = 0;
    while (len > 1) {
        sum += *(data++);
        len -= 2;
    }
    if (len == 1) {
        sum += *((uint8_t *) data);
    }
    while (sum >> 16) {
        sum = (sum & 0xFFFF) + (sum >> 16);
    }
    return ~sum;
}

// 发送ICMP回显请求报文
void ping_request(uint16_t seq) {
    icmp_packet_t *icmp_packet;
    uint8_t send_buf[ICMP_HEADER_SIZE + 4];  // 报文头部大小加上数据大小
    uint16_t checksum_val;
    int i;

    memset(send_buf, 0, sizeof(send_buf));
    icmp_packet = (icmp_packet_t *) send_buf;
    icmp_packet->type = ICMP_ECHO_REQUEST;
    icmp_packet->code = 0;
    icmp_packet->identifier = htons(rand() & 0xFFFF);
    icmp_packet->sequence_number = htons(seq);
    for (i = 0; i < 4; i++) {
        icmp_packet->data[i] = rand() & 0xFF;
    }
    checksum_val = checksum(icmp_packet, ICMP_HEADER_SIZE + 4);
    icmp_packet->checksum = htons(checksum_val);

    w5500_send((uint8_t *) icmp_packet, ICMP_HEADER_SIZE + 4);
}

// 接收ICMP回显应答报文
int ping_reply(uint16_t seq) {
    icmp_packet_t *icmp_packet;
    uint8_t recv_buf[ICMP_HEADER_SIZE + 4];  // 报文头部大小加上数据大小
    uint16_t checksum_val;
    uint16_t identifier;
    uint16_t sequence_number;
    int i, len;

    len = w5500_recv(recv_buf, sizeof(recv_buf));
    if (len < ICMP_HEADER_SIZE + 4) {
        return -1;
    }
    icmp_packet = (icmp_packet_t *) recv_buf;
    if (icmp_packet->type != ICMP_ECHO_REPLY) {
        return -1;
    }
    identifier = ntohs(icmp_packet->identifier);
    sequence_number = ntohs(icmp_packet->sequence_number);
    if (identifier != (rand() & 0xFFFF) || sequence_number != seq) {
        return -1;
    }
    checksum_val = ntohs(icmp_packet->checksum);
    icmp_packet->checksum = 0;
    if (checksum(icmp_packet, len - ICMP_HEADER_SIZE) != checksum_val) {
        return -1;
    }
    printf("Reply from %d.%d.%d.%d: time=%dms\n", 
        IP_ADDR[0], IP_ADDR[1], IP_ADDR[2], IP_ADDR[3], 
        PING_TIMEOUT - w5500_ping_time());
    return 0;
}

// ping测试主函数
void ping_test(void) {
    int i, ret;
    uint16_t seq;

    w5500_init();
    for (i = 0; i < PING_COUNT; i++) {
        seq = ICMP_SEQ_NUMBER + i;
        ping_request(seq);
        ret = w5500_ping_wait(PING_TIMEOUT);
        if (ret < 0) {
            printf("Request timed out.\n");
        } else {
            ping_reply(seq);
        }
    }
    w5500_cleanup();
}

int main(void) {
    ping_test();
    return 0;
}

需要注意的是，该示例代码使用了W5500库中的w5500_init、w5500_send、w5500_recv、w5500_ping_time、w5500_ping_wait和w5500_cleanup函数，需要根据具体情况修改这些函数的实现。