#include <windows.h>
#include <winsock.h>
#include <stdio.h>
#include <stdlib.h>

#define MAX_PACKET_SIZE 65516

WSADATA        WsaData;

int _CRTAPI1 main(int argc, char **argv, char **envp)
{
    SOCKET serve_me;
    char *dstName;
    int dstPort;
    struct sockaddr addr;
    int remotelen;
    struct sockaddr remoteaddr;
    struct sockaddr_in *in_addr = (struct sockaddr_in *)&addr;
    struct in_addr  inaddr;
    int   count;
    int   pktsize;
    char *buf;
    int   i;
    int   err;
	int   rcvlen;

    if(argc<5){
            printf("usage: upongcly hostaddr port pktsize pktcnt\n");
            exit(4);
    }

    dstName = argv[1];
    dstPort = atoi(argv[2]);
    pktsize = atoi(argv[3]);
    count = atoi(argv[4]);

    if (pktsize > MAX_PACKET_SIZE) {
        printf("max packet size is 1460\n");
        exit(1);
    }

    err = WSAStartup( 0x0101, &WsaData );
    if ( err == SOCKET_ERROR ) {
        printf("tpongsrv: WSAStartup %d:", GetLastError());
	exit(1);
    }

    if ((buf = malloc(pktsize)) == NULL) {
        printf("out of memory\n");
        exit(1);
    }

	for (i = 0; i < pktsize; i++ ) {
		buf[i] = 'a' + (i % 25);
	}

    if((serve_me=socket(PF_INET,SOCK_DGRAM,0))==INVALID_SOCKET){
            printf("Died on socket()\n");
            exit(4);
    }

    memset(&addr,0,sizeof(addr));
    in_addr->sin_family = AF_INET;
    in_addr->sin_port = 0;
    in_addr->sin_addr.s_addr = 0;


    if(bind(serve_me,&addr,sizeof(addr))==SOCKET_ERROR){
            printf("Died on bind() with %d\n", WSAGetLastError());
            closesocket(serve_me);
            exit(9);
    }

	memset(&addr,0,sizeof(addr));
	in_addr->sin_family = AF_INET;
        in_addr->sin_port = htons(dstPort);
	in_addr->sin_addr.s_addr = inet_addr(dstName);
	
	if(connect(serve_me,&addr,sizeof(addr))==SOCKET_ERROR){
		printf("Died on connect() with %d\n", WSAGetLastError());	
		closesocket(serve_me);
		exit(9);
	}

    if (count == -1) {
        for (; ; ) {
            if( send(
                    serve_me,
                    buf,
                    pktsize,
                    0
                    )
                 ==SOCKET_ERROR
              ){
                printf("sendto failed %d\n",WSAGetLastError());
                exit(9);
            }
            remotelen = sizeof(remoteaddr);
            if( recv(
                    serve_me,
                    buf,
                    pktsize,
                    0
                    )
                 ==SOCKET_ERROR
              ){
                printf("recvfrom failed %d\n",WSAGetLastError());
                exit(9);
            }
        }
    }
    else {
        for(i=0; i < count; i++) {
            if( send(
                    serve_me,
                    buf,
                    pktsize,
                    0
                    )
                 ==SOCKET_ERROR
              ){
                printf("sendto failed %d\n",WSAGetLastError());
   			    closesocket(serve_me);
                exit(9);
            }
            remotelen = sizeof(remoteaddr);
            rcvlen = recv(serve_me, buf, pktsize, 0 );

            if (rcvlen == SOCKET_ERROR) {
                printf("recvfrom failed %d\n",WSAGetLastError());
   			    closesocket(serve_me);
                exit(9);
            }

			if (rcvlen != pktsize) {
				printf(
				    "Request size %d, response size %d!!\n",
					pktsize,
					rcvlen
					);
				closesocket(serve_me);
				exit(9);
			}

	        for (i = 0; i < pktsize; i++ ) {
		        if (buf[i] != ('a' + (i % 25))) {
					printf("Response differs at byte %d\n", i);
					closesocket(serve_me);
					exit(9);
                }
	        }
        }
    }

    closesocket(serve_me);
}


int init_net()
{
    WORD wVersionRequired;
    WSADATA versionInfo;

    wVersionRequired = 1<<8 | 0;
    if(WSAStartup(wVersionRequired, &versionInfo)){
            printf("died in WSAStartup() %d\n",WSAGetLastError());
            exit(9);
    }
    return 0;
}