#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>

char data[20480];

/*******************************************************

 test tool to send UDP packets up to 20480 in size to a port

 send_udp host port packets packetsize

 Useful for network load tests, UDP throughput

 *******************************************************/


main(int argc,char *argv[])
{
        int sock,ii,port_no,packets,packetsize;
        struct sockaddr_in name;
        struct hostent *hp;

        if ((argv[1] == NULL) || (argv[2] == NULL) || (argv[3] == NULL) || (argv[4] == NULL)) {
                printf("usage: %s host port packets packetsize\n",argv[0]);
        }

        hp = gethostbyname(argv[1]);    
        if (hp == 0) { 
                fprintf(stderr,"%s: unknown host\n",argv[1]);  
                exit(1);       
        }      

	port_no = atoi(argv[2]);
	packets = atoi(argv[3]);
	packetsize = atoi(argv[4]);

        sock = socket(AF_INET,SOCK_DGRAM,0);
        if (sock < 0) {
                perror("opening datagram socket");
                exit(1);
        }

	name.sin_family = AF_INET;
	name.sin_addr.s_addr = INADDR_ANY;
	name.sin_port = 0;
	if (bind(sock,(struct sockaddr *)&name,sizeof(name)) < 0) {
		perror("binding datagram socket");
		exit(1);
	}

        bcopy((char *)hp->h_addr,(char *)&name.sin_addr,hp->h_length);
        name.sin_family = AF_INET;
        name.sin_port = htons(port_no);

        for (ii = 0; ii < packets; ii++) {
                if (sendto(sock,data,packetsize,0,(struct sockaddr *)&name,sizeof(name)) < 0) {
                        perror("sending datagram message");
                }
        }
        close(sock);
        exit(0);
}