utils.c

#include <pthread.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

//#include "global_server_variables.h"

int opentcpsock(char *hostip, int port){
	//DECLARE VARIABLES FOR IP CONNECTIONS
	char	datacode,ipaddr[16];
	int		sock,data,temp;
	struct	sockaddr_in	server;
	struct	hostent		*hp, *gethostbyname();
	float	ftime;
	int		buffer2,channel2,sample2i,option,optionlen;
	int		do_scan_rx[4];
	struct 	protent*	protocol_info;

	//hostip=HOST;
	//port=DEFAULT_PORT;

	//SET UP IP CONNECTION
	sock=socket(AF_INET, SOCK_STREAM, 0);
	if( (sock < 0) ) {
		perror("opening stream socket");
		exit(1);
	}
	server.sin_family=AF_INET;
	hp=gethostbyname(hostip);
	if( hp == 0 ){
		fprintf(stderr, "unknown host");
		exit(2);
	}
	memcpy(&server.sin_addr, hp->h_addr, hp->h_length);
	server.sin_port=htons(port);
	temp=connect(sock, (struct sockaddr *)&server, sizeof(server));
	if( temp < 0){
		perror("connecting stream socket");
		return -1;
	}


	//protocol_info=getprotobyname("tcp");
	//printf("protocol name = %s\n",protocol_info->p_name);
	option=TCP_NODELAY;
	optionlen=4;
	temp=setsockopt(sock,6,TCP_NODELAY,&option,optionlen);
	temp=getsockopt(sock,6,TCP_NODELAY,&option,&optionlen);
//	printf("temp=%d  optionlen=%d option=%d\n",temp,optionlen,option);
	optionlen=4;
	option=32768;
	temp=setsockopt(sock,SOL_SOCKET,SO_SNDBUF,&option,optionlen);
	temp=getsockopt(sock,SOL_SOCKET,SO_SNDBUF,&option,&optionlen);
//	printf("temp=%d  optionlen=%d option=%d\n",temp,optionlen,option);
	optionlen=4;
	option=32768;
	temp=setsockopt(sock,SOL_SOCKET,SO_RCVBUF,&option,optionlen);
	temp=getsockopt(sock,SOL_SOCKET,SO_RCVBUF,&option,&optionlen);
//	printf("temp=%d  optionlen=%d option=%d\n",temp,optionlen,option);

    return sock;
}

int send_data(int fd,void  *buf,size_t buflen)
{
     int cc=0,total=0;
     while (buflen > 0) {
          cc = send(fd, buf, buflen, MSG_NOSIGNAL);
          if (cc == -1) {
               return cc;
          }
          if (cc == 0) {
            return -1;
          }

          buf += cc;
          total += cc;
          buflen -= cc;
     }
     return total;
}

int recv_data(int fd,void *buf,size_t buflen)
{
     int cc=0,total=0;
     while (buflen > 0) {
          cc = recv(fd, buf, buflen, MSG_NOSIGNAL);
          if (cc == -1) {
               return cc;
          }
          if (cc == 0) {
            return -1;
          }
          buf += cc;
          total += cc;
          buflen -= cc;
     }
     return total;

}