Notes

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <arpa/inet.h>

#define PORT 8080
#define MAX_SIZE 1024

// Function to calculate Hamming Code redundant bits
void calculateRedundantBits(char dataword[], char redundantBits[]) {
int d[7], p1, p2, p4, p8;
int i, d_len = strlen(dataword);

// Ensure the dataword is 7 bits long
if (d_len != 7) {
printf("Error: Dataword must be 7 bits long!n");
strcpy(redundantBits, "ERROR");
return;
}

// Convert dataword characters to integer array
for (i = 0; i < 7; i++) {
d[i] = dataword[i] - '0';
}

// Compute redundant bits using Hamming Code (for 7-bit dataword)
p1 = d[0] ^ d[1] ^ d[3] ^ d[4] ^ d[6]; // Parity bit 1
p2 = d[0] ^ d[2] ^ d[3] ^ d[5] ^ d[6]; // Parity bit 2
p4 = d[1] ^ d[2] ^ d[3]; // Parity bit 4
p8 = d[4] ^ d[5] ^ d[6]; // Parity bit 8

// Store redundant bits as a string
sprintf(redundantBits, "%d%d%d%d", p1, p2, p4, p8);
}

int main() {
int server_fd, client_fd;
struct sockaddr_in server_addr, client_addr;
socklen_t addr_size;
char dataword[MAX_SIZE], redundantBits[5];

// Create socket
server_fd = socket(AF_INET, SOCK_STREAM, 0);
if (server_fd == -1) {
perror("Socket creation failed");
exit(1);
}

server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(PORT);
server_addr.sin_addr.s_addr = INADDR_ANY;

// Bind socket to the port
if (bind(server_fd, (struct sockaddr*)&server_addr, sizeof(server_addr)) == -1) {
perror("Binding failed");
exit(1);
}

// Listen for client connections
if (listen(server_fd, 1) == -1) {
perror("Listening failed");
exit(1);
}

printf("Server is listening on port %d...n", PORT);

addr_size = sizeof(client_addr);
client_fd = accept(server_fd, (struct sockaddr*)&client_addr, &addr_size);
if (client_fd == -1) {
perror("Client connection failed");
exit(1);
}

// Receive dataword from client
recv(client_fd, dataword, MAX_SIZE, 0);
printf("Received Dataword: %sn", dataword);

// Compute redundant bits
calculateRedundantBits(dataword, redundantBits);

// Print only redundant bits
printf("Redundant Bits: %sn", redundantBits);

// Close sockets
close(client_fd);
close(server_fd);
return 0;
}