file transfer using UDP protocol - c

Question

I have a server and client code which I am using to transfer file from server to client. After compiling, instead of copying my whole file from server directory to client directory, it shows the content of file on the terminal. I am new to c and this my assignment. I know UDP is not the best possible way to implement file transfer application. But this is how I have to do it.
This is server side:
#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#define IP_PROTOCOL 0
#define PORT_NO 15050
#define NET_BUF_SIZE 32
#define cipherKey 'S'
#define sendrecvflag 0
#define nofile "File Not Found!"
// funtion to clear buffer
void clearBuf(char* b)
{
int i;
for (i = 0; i < NET_BUF_SIZE; i++)
b[i] = '\0';
}
// funtion to encrypt
char Cipher(char ch)
{
return ch ^ cipherKey;
}
// funtion sending file
int sendFile(FILE* fp, char* buf, int s)
{
int i, len;
if (fp == NULL) {
strcpy(buf, nofile);
len = strlen(nofile);
buf[len] = EOF;
for (i = 0; i <= len; i++)
buf[i] = Cipher(buf[i]);
return 1;
}
char ch, ch2;
for (i = 0; i < s; i++) {
ch = fgetc(fp);
ch2 = Cipher(ch);
buf[i] = ch2;
if (ch == EOF)
return 1;
}
return 0;
}
// driver code
int main()
{
int sockfd, nBytes;
struct sockaddr_in addr_con;
int addrlen = sizeof(addr_con);
addr_con.sin_family = AF_INET;
addr_con.sin_port = htons(PORT_NO);
addr_con.sin_addr.s_addr = INADDR_ANY;
char net_buf[NET_BUF_SIZE];
FILE* fp;
// socket()
sockfd = socket(AF_INET, SOCK_DGRAM, IP_PROTOCOL);
if (sockfd < 0)
printf("\nfile descriptor not received!!\n");
else
printf("\nfile descriptor %d received\n", sockfd);
// bind()
if (bind(sockfd, (struct sockaddr*)&addr_con, sizeof(addr_con)) == 0)
printf("\nSuccessfully binded!\n");
else
printf("\nBinding Failed!\n");
while (1) {
printf("\nWaiting for file name...\n");
// receive file name
clearBuf(net_buf);
nBytes = recvfrom(sockfd, net_buf,
NET_BUF_SIZE, sendrecvflag,
(struct sockaddr*)&addr_con, &addrlen);
fp = fopen(net_buf, "r");
printf("\nFile Name Received: %s\n", net_buf);
if (fp == NULL)
printf("\nFile open failed!\n");
else
printf("\nFile Successfully opened!\n");
while (1) {
if (sendFile(fp, net_buf, NET_BUF_SIZE)) {
sendto(sockfd, net_buf, NET_BUF_SIZE,
sendrecvflag,
(struct sockaddr*)&addr_con, addrlen);
break;
}
// send
sendto(sockfd, net_buf, NET_BUF_SIZE,
sendrecvflag,
(struct sockaddr*)&addr_con, addrlen);
clearBuf(net_buf);
}
if (fp != NULL)
fclose(fp);
}
return 0;
}
This is client side:
#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#define IP_PROTOCOL 0
#define IP_ADDRESS "127.0.0.1" // localhost
#define PORT_NO 15050
#define NET_BUF_SIZE 32
#define cipherKey 'S'
#define sendrecvflag 0
// funtion to clear buffer
void clearBuf(char* b)
{
int i;
for (i = 0; i < NET_BUF_SIZE; i++)
b[i] = '\0';
}
// function for decryption
char Cipher(char ch)
{
return ch ^ cipherKey;
}
// function to receive file
int recvFile(char* buf, int s)
{
int i;
char ch;
for (i = 0; i < s; i++) {
ch = buf[i];
ch = Cipher(ch);
if (ch == EOF)
return 1;
else
printf("%c", ch);
}
return 0;
}
// driver code
int main()
{
int sockfd, nBytes;
struct sockaddr_in addr_con;
int addrlen = sizeof(addr_con);
addr_con.sin_family = AF_INET;
addr_con.sin_port = htons(PORT_NO);
addr_con.sin_addr.s_addr = inet_addr(IP_ADDRESS);
char net_buf[NET_BUF_SIZE];
FILE* fp;
// socket()
sockfd = socket(AF_INET, SOCK_DGRAM, IP_PROTOCOL);
if (sockfd < 0)
printf("\nfile descriptor not received!!\n");
else
printf("\nfile descriptor %d received\n", sockfd);
while (1) {
printf("\nPlease enter file name to receive:\n");
scanf("%s", net_buf);
sendto(sockfd, net_buf, NET_BUF_SIZE, sendrecvflag, (struct sockaddr*)&addr_con, addrlen);
printf("\n---------Data Received---------\n");
while (1) {
// receive
clearBuf(net_buf);
nBytes = recvfrom(sockfd, net_buf, NET_BUF_SIZE, sendrecvflag, (struct sockaddr*)&addr_con, &addrlen);
// process
if (recvFile(net_buf, NET_BUF_SIZE)) {
break;
}
}
printf("\n-------------------------------\n");
}
return 0;
}
I need to copy file from Server to Client