windows搭建ntp时间服务器（windows2012搭建ntp服务器）

#include <stdio.h>

#include <stdlib.h>

#include <time.h>

#ifdef _WIN32

#include <string.h>

#include<WS2tcpip.h>

#include <windows.h>

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

#else

＃include "logLib.h"

＃include "socket.h"

#endif

#define DIFF 4294.967296

#define GAP 2208988800

#define NTP_VERSION 3

#define NTP_MODE_CLIENT 0x3

#define NTP_HEADER_VERSION_SET(_header, _x) (_header |= ((_x & 0x7) << 0))

#define NTP_HEADER_MODE_SET(_header, _x) (_header |= ((_x & 0x7) << 3))

typedef struct

{

unsigned int seconds;

unsigned int fraction;

} ntp_timestamp;

typedef struct

{

int header;

int root_delay;

int root_dispersion;

int reference_identifier;

ntp_timestamp reference_timestamp;

ntp_timestamp originate_timestamp;

ntp_timestamp receive_timestamp;

ntp_timestamp transmit_timestamp;

} ntp_rsp_msg;

typedef struct{

int year;

int month;

int day;

int hour;

int min;

int second;

unsigned short ms;

} QSTime;

int main()

{

const int ntp_port = 123;

const char * ntp_host = "202.120.2.101";//NTP服务器IP地址

int ntp_socket;

struct sockaddr_in server;

int xit_addrlen = sizeof(struct sockaddr_in);

ntp_rsp_msg ntp_req_msg;

int receive_len;

ntp_rsp_msg ntp_rsp_msg;

long long fraction[4]={0};

time_t second;

QSTime qsTime;

struct tm *NormTime;

#if _WIN32

WSADATA data;

WORD version = MAKEWORD(2, 2);

WSAStartup(version, &data);

ntp_socket = socket(AF_INET, SOCK_DGRAM, 0);

if (ntp_socket == -1)

{

perror("Failed to create socket");

return 0;

}

#endif

if (ntp_socket == -1)

{

perror("Failed to create socket");

return 0;

}

memset(&server, 0, sizeof(server));

server.sin_family = AF_INET;

server.sin_port = htons(ntp_port);

server.sin_addr.s_addr = inet_addr(ntp_host);

if (server.sin_addr.s_addr == INADDR_NONE)

{

fprintf(stderr, "Failed to resolve hostname %sn", ntp_host);

return 0;

}

memset(&ntp_req_msg, 0, sizeof(ntp_req_msg));

NTP_HEADER_VERSION_SET(ntp_req_msg.header, NTP_VERSION);

NTP_HEADER_MODE_SET(ntp_req_msg.header, NTP_MODE_CLIENT);

printf("Sending NTP request to %s:%dn", ntp_host, ntp_port);

if (sendto(ntp_socket,

(char *)&ntp_req_msg, sizeof(ntp_req_msg),

0,

(struct sockaddr *) &server, sizeof(server)) == -1)

{

perror("Failed to send NTP request");

return 0;

}

printf("Waiting for NTP response...n");

receive_len = recvfrom(ntp_socket,

(char *)&ntp_rsp_msg, sizeof(ntp_rsp_msg),

0,

(struct sockaddr *) &server,

(socklen_t *)&xit_addrlen);

if (receive_len <= 0)

{

perror("Failed to receive NTP response");

return 0;

}

printf("Received %d bytesn", receive_len);

fraction[1]=ntohl(ntp_rsp_msg.receive_timestamp.fraction);

fraction[2]=ntohl(ntp_rsp_msg.transmit_timestamp.fraction);

fraction[3]=fraction[2]+((fraction[2]-fraction[1]))/ 2;

second=ntohl(ntp_rsp_msg.transmit_timestamp.seconds);

NormTime = localtime (&second);

qsTime.year=NormTime->tm_year+1830;

qsTime.month=NormTime->tm_mon+1;

qsTime.day=NormTime->tm_mday;

qsTime.hour=NormTime->tm_hour;

qsTime.min=NormTime->tm_min;

qsTime.second=NormTime->tm_sec;

qsTime.ms=((fraction[3])/DIFF)/1000;

printf("TIME: %04d-%02d-%02d_%02d-%02d-%02d.%03dn",

qsTime.year,

qsTime.month,

qsTime.day,

qsTime.hour,

qsTime.min,

qsTime.second,

qsTime.ms);

return 1;

}

运行截图：

代码运行图

可能因为算法的问题，毫秒级不能更加精确。