Windows C++ ping命令实现

摘录知名博主的源码，亲测可以，如下：

#include 
#include 
#pragma comment(lib, "ws2_32.lib")

// IP数据包头结构
typedef struct iphdr
{
    unsigned int headLen:4;
    unsigned int version:4;
    unsigned char tos;
    unsigned short totalLen;
    unsigned short ident;
    unsigned short fragAndFlags;
    unsigned char ttl;
    unsigned char proto;
    unsigned short checkSum;
    unsigned int sourceIP;
    unsigned int destIP;
}IpHeader;

// ICMP数据头结构
typedef struct ihdr
{
    unsigned char iType;
    unsigned char iCode;
    unsigned short iCheckSum;
    unsigned short iID;
    unsigned short iSeq;
    unsigned long  timeStamp;
}IcmpHeader;

// 计算ICMP包的校验和(发送前要用)
unsigned short checkSum(unsigned short *buffer, int size)
{
    unsigned long ckSum = 0;

    while(size > 1)
    {
        ckSum += *buffer++;
        size -= sizeof(unsigned short);
    }

    if(size)
    {
        ckSum += *(unsigned char*)buffer;
    }

    ckSum = (ckSum >> 16) + (ckSum & 0xffff);
    ckSum += (ckSum >>16);

    return unsigned short(~ckSum);
}

// 填充ICMP请求包的具体参数
void fillIcmpData(char *icmpData, int dataSize)
{
    IcmpHeader *icmpHead = (IcmpHeader*)icmpData;
    icmpHead->iType = 8;  // 8表示请求包
    icmpHead->iCode = 0;
    icmpHead->iID = (unsigned short)GetCurrentThreadId();
    icmpHead->iSeq = 0;
    icmpHead->timeStamp = GetTickCount();
    char *datapart = icmpData + sizeof(IcmpHeader);
    memset(datapart, 'x', dataSize - sizeof(IcmpHeader)); // 数据部分为xxx..., 实际上有32个x
    icmpHead->iCheckSum = checkSum((unsigned short*)icmpData, dataSize); // 千万要注意，这个一定要放到最后
}

// 对返回的IP数据包进行解析，定位到ICMP数据
int decodeResponse(char *buf, int bytes, struct sockaddr_in *from, int tid)
{
    IpHeader *ipHead = (IpHeader *)buf;
    unsigned short ipHeadLen = ipHead->headLen * 4 ;
    if (bytes < ipHeadLen + 8) // ICMP数据不完整, 或者不包含ICMP数据
    {
        return -1;
    }

    IcmpHeader *icmpHead = (IcmpHeader*)(buf + ipHeadLen);  // 定位到ICMP包头的起始位置
    if (icmpHead->iType != 0)   // 0表示回应包
    {
        return -2;
    }

    if (icmpHead->iID != (unsigned short)tid) // 理应相等
    {
        return -3;
    }

    int time = GetTickCount() - (icmpHead->timeStamp); // 返回时间与发送时间的差值
    if(time >= 0)
    {
        return time;
    }

    return -4; // 时间错误
}

// ping操作
int ping(const char *ip, unsigned int timeout)
{
    // 网络初始化
    WSADATA wsaData;
    WSAStartup(MAKEWORD(1, 1), &wsaData);
    unsigned int sockRaw = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);  // 注意，第三个参数非常重要，指定了是icmp
    setsockopt(sockRaw, SOL_SOCKET, SO_RCVTIMEO, (char*)&timeout, sizeof(timeout));  // 设置套接字的接收超时选项
    setsockopt(sockRaw, SOL_SOCKET, SO_SNDTIMEO, (char*)&timeout, sizeof(timeout));  // 设置套接字的发送超时选项

    // 准备要发送的数据
    int  dataSize = sizeof(IcmpHeader) + 32; // 待会儿会有32个x
    char icmpData[1024] = {0};
    fillIcmpData(icmpData, dataSize);
    unsigned long startTime = ((IcmpHeader *)icmpData)->timeStamp;

    // 远程通信端
    struct sockaddr_in dest;
    memset(&dest, 0, sizeof(dest));
    struct hostent *hp = gethostbyname(ip);
    memcpy(&(dest.sin_addr), hp->h_addr, hp->h_length);
    dest.sin_family = hp->h_addrtype;

    // 发送数据
    sendto(sockRaw, icmpData, dataSize, 0, (struct sockaddr*)&dest, sizeof(dest));

    int iRet = -1;
    struct sockaddr_in from;
    int fromLen = sizeof(from);
    while(1)
    {
        // 接收数据
        char recvBuf[1024] = {0};
        int iRecv = recvfrom(sockRaw, recvBuf, 1024, 0, (struct sockaddr*)&from, &fromLen);
        int time  = decodeResponse(recvBuf, iRecv, &from, GetCurrentThreadId());
        if(time >= 0)
        {
            iRet = 0;   // ping ok
            break;
        }
        else if( GetTickCount() - startTime >= timeout || GetTickCount() < startTime)
        {
            iRet = -1;  // ping超时
            break;
        }
    }

    // 释放
    closesocket(sockRaw);
    WSACleanup();

    return iRet;
}

// 主函数
int main()
{
    // 请用格式合理的ip地址
    char szIPs[][16] =
    {
        "192.168.1.1",
        "192.168.1.100",
        "192.168.1.101"
    };

    int i = 0;
    int size = sizeof(szIPs) / sizeof(szIPs[0]);
    for(i = 0; i < size; i++)
    {
        int iRet = ping(szIPs[i], 3000); // 超时时间为3000ms

        if(0 == iRet)
        {
            printf("%s ONLINE\n", szIPs[i]);
        }
        else if(-1 == iRet)
        {
            printf("%s TIMEOUT\n", szIPs[i]);
        }
        else
        {
            printf("Unkonw");
        }
    }

    return 0;
}