liteping.c

简单的linux下ping代码

#include <stdio.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/signal.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <netdb.h>

int main(int argc, char ** argv)
{
	struct timeval tv;
	struct timeval * sendtime;
	struct timeval recvtime;
	struct timeval different;
	struct sockaddr_in host;
	struct sockaddr_in recvhost;
	struct hostent *address;
	struct icmphdr *sendhdr;
	struct icmphdr *recvhdr;
	struct ip* iphdr;
	
	int sock;
	int loop;
	int ret;
	int max_loop_time = 10;
	int addrlen = sizeof(struct sockaddr);
	int sendlen = sizeof(struct icmphdr) + sizeof(long);
	int ttl = 64;
	int hdrlen = sizeof(struct icmphdr) + sizeof(struct ip);
	int seq = 0;
	
	char * sendbuf[1024];
	char * recvbuf[1024];
	
	printf("\n~~~ Lite Ping By aLFRED ~~~\n");
	switch( argc )
	{
		case 3:
			max_loop_time = atoi(argv[2]);
		case 2:
			printf("~~~ Receive 1 parameter:\n");
			printf("~~~ Param 1: %s\n", argv[1]);
			if( 3 == argc)
				printf("~~~ Param 2: %s times loop\n", argv[2]);
			printf("\n");
			tv.tv_sec = 5;
			tv.tv_usec = 0;
			break;
		default:
			printf("~~~ Usage: %s IP(or hostname) [number of loop time]\n\n", argv[0]);
			exit(0);
			break;
	}
	
	sock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP);
	setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(struct timeval));
	setsockopt(sock, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(struct timeval));
	setsockopt(sock, IPPROTO_IP, IP_TTL, (int *)&ttl, sizeof(int));
	
	host.sin_family = AF_INET;
	if( (host.sin_addr.s_addr = inet_addr(argv[1])) != 0xffff )
	{
		address = gethostbyname( argv[1] );
		if( address )
		{
			memcpy(&host.sin_addr , address->h_addr, address->h_length);
		}
		else
		{
			printf("~~~ The hostname is wrong.\n\n");
			exit(1);
		}
	}
	printf("~~~ Ping %s(%s):\n",argv[1],inet_ntoa(host.sin_addr));
	
	sendhdr = (struct icmphdr *)sendbuf;
	sendhdr -> type = ICMP_ECHO;
	sendhdr -> code = 0;
	sendhdr -> checksum = 0;
	(sendhdr -> un).echo.id = (unsigned short)getpid();
	(sendhdr -> un).echo.sequence = seq;
	
	for(loop = 0; loop < max_loop_time ; loop++ )
	{
		(sendhdr -> un).echo.sequence = seq++;
		sendtime = (struct timeval *)(sendbuf+sizeof(struct icmphdr));
		gettimeofday(sendtime, NULL);
		if(sendto(sock, sendbuf, sendlen, 0, (struct sockaddr*)&host, addrlen)<0)
		{
			printf("~~~ Error\n",loop);
			continue;
		}
		ret = recvfrom(sock, recvbuf, 1024, 0,  (struct sockaddr*)&recvhost, &addrlen);
		gettimeofday(&recvtime, NULL);
		if (ret < 0)
 		{
			printf("~~~ Error\n",loop);
			continue;
		}
		different.tv_sec = recvtime.tv_sec - sendtime->tv_sec;
		different.tv_usec = recvtime.tv_usec - sendtime->tv_usec;
		
		iphdr = (struct ip*)recvbuf;
		recvhdr = (struct icmphdr*)(recvbuf + 20);
		printf("~~~ Reply from %s: ", inet_ntoa(recvhost.sin_addr));
		printf("%d bytes  ",ret);
		printf("ttl=%d  ",iphdr->ip_ttl);
		printf("time=%1.4fms\n",(different.tv_sec)*1000.0 + (different.tv_usec)/1000.0);
	}
	
	close(sock);
	printf("\n");
	
	return 1;
}