Socket Programming

client.c

/****************** SERVER CODE ****************/

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>

int main(){
  int welcomeSocket, newSocket;
  char buffer[1024];
  struct sockaddr_in serverAddr;
  struct sockaddr_storage serverStorage;
  socklen_t addr_size;

  /*---- Create the socket. The three arguments are: ----*/
  /* 1) Internet domain 2) Stream socket 3) Default protocol (TCP in this case) */
  welcomeSocket = socket(PF_INET, SOCK_STREAM, 0);
  
  /*---- Configure settings of the server address struct ----*/
  /* Address family = Internet */
  serverAddr.sin_family = AF_INET;
  /* Set port number, using htons function to use proper byte order */
  serverAddr.sin_port = htons(7891);
  /* Set IP address to localhost */
  serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
  /* Set all bits of the padding field to 0 */
  memset(serverAddr.sin_zero, '\0', sizeof serverAddr.sin_zero);  

  /*---- Bind the address struct to the socket ----*/
  bind(welcomeSocket, (struct sockaddr *) &serverAddr, sizeof(serverAddr));

  /*---- Listen on the socket, with 5 max connection requests queued ----*/
  if(listen(welcomeSocket,5)==0)
    printf("Listening\n");
  else
    printf("Error\n");

  /*---- Accept call creates a new socket for the incoming connection ----*/
  addr_size = sizeof serverStorage;
  newSocket = accept(welcomeSocket, (struct sockaddr *) &serverStorage, &addr_size);

  /*---- Send message to the socket of the incoming connection ----*/
  strcpy(buffer,"Hello World\n");
  send(newSocket,buffer,13,0);

  return 0;
}

hammingcode.c

#include<stdio.h>
void main() {
    int data[7],rec[7],i,c1,c2,c3,c;
    printf("this works for message of 4bits in size \nenter message bit one by one:  ");
    scanf("%d%d%d%d",&data[0],&data[1],&data[2],&data[4]);
    data[6]=data[0]^data[2]^data[4];
    data[5]=data[0]^data[1]^data[4];
    data[3]=data[0]^data[1]^data[2];
    printf("\nthe encoded bits are given below: \n");
    for (i=0;i<7;i++) {
        printf("%d ",data[i]);
    }
    printf("\nenter the received data bits one by one: ");
    for (i=0;i<7;i++) {
        scanf("%d",&rec[i]);
    }
    c1=rec[6]^rec[4]^rec[2]^rec[0];
    c2=rec[5]^rec[4]^rec[1]^rec[0];
    c3=rec[3]^rec[2]^rec[1]^rec[0];
    c=c3*4+c2*2+c1 ;
    if(c==0) {
        printf("\ncongratulations there is no error: ");
    } else {
        printf("\nerror on the postion: %d\nthe correct message is \n",c);
        if(rec[7-c]==0)
            rec[7-c]=1;
        else
            rec[7-c]=0;
        for (i=0;i<7;i++) {
            printf("%d ",rec[i]);
        }
    }

}

server.c

/****************** SERVER CODE ****************/

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>

int main(){
  int welcomeSocket, newSocket;
  char buffer[1024];
  struct sockaddr_in serverAddr;
  struct sockaddr_storage serverStorage;
  socklen_t addr_size;

  /*---- Create the socket. The three arguments are: ----*/
  /* 1) Internet domain 2) Stream socket 3) Default protocol (TCP in this case) */
  welcomeSocket = socket(PF_INET, SOCK_STREAM, 0);
  
  /*---- Configure settings of the server address struct ----*/
  /* Address family = Internet */
  serverAddr.sin_family = AF_INET;
  /* Set port number, using htons function to use proper byte order */
  serverAddr.sin_port = htons(7891);
  /* Set IP address to localhost */
  serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
  /* Set all bits of the padding field to 0 */
  memset(serverAddr.sin_zero, '\0', sizeof serverAddr.sin_zero);  

  /*---- Bind the address struct to the socket ----*/
  bind(welcomeSocket, (struct sockaddr *) &serverAddr, sizeof(serverAddr));

  /*---- Listen on the socket, with 5 max connection requests queued ----*/
  if(listen(welcomeSocket,5)==0)
    printf("Listening\n");
  else
    printf("Error\n");

  /*---- Accept call creates a new socket for the incoming connection ----*/
  addr_size = sizeof serverStorage;
  newSocket = accept(welcomeSocket, (struct sockaddr *) &serverStorage, &addr_size);

  /*---- Send message to the socket of the incoming connection ----*/
  strcpy(buffer,"Hello World\n");
  send(newSocket,buffer,13,0);

  return 0;
}

two-way-client.c

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
int main()
{
    int clientSocket,newSocket;
    struct sockaddr_in serverAddr;

    socklen_t addr_size;
    char buffer[1024];

    clientSocket = socket(AF_INET,SOCK_STREAM,0);

    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(7891);
    serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");

    memset(serverAddr.sin_zero,'\0',sizeof(serverAddr.sin_zero));

    addr_size = sizeof(serverAddr);
    connect(clientSocket,(struct sockaddr *) &serverAddr, addr_size);

    recv(clientSocket,buffer,1024,0);

    printf("DATA RECEIVED : %s\n",buffer);

    printf("Enter MSG : ");
    scanf("%s",buffer);
    send(clientSocket,buffer,sizeof(buffer),0);
    recv(clientSocket,buffer,1024,0);

    printf("DATA RECEIVED : %s\n",buffer);
    return 0;
}

two-way-server.c

#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
int main()
{
    struct sockaddr_in serverAddr;
    struct sockaddr_storage serverStorage;

    int welcomeSocket, newSocket;
    char buffer[1024];
    welcomeSocket = socket(AF_INET,SOCK_STREAM,0);
    
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(7891);
    serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");

    memset(serverAddr.sin_zero,'\0',sizeof(serverAddr.sin_zero));

    bind(welcomeSocket, (struct sockaddr *) &serverAddr, sizeof(serverAddr));

    if(listen(welcomeSocket,5)==0) {
        printf("Listening\n");
    } else {
        printf("Error\n");
    }

    socklen_t addr_size;

    addr_size = sizeof(serverStorage);
    newSocket = accept(welcomeSocket, (struct sockaddr *) &serverAddr, &addr_size);

    strcpy(buffer,"Server Started\n");
    send(newSocket,buffer,sizeof(buffer),0);
    recv(newSocket,buffer,1024,0);

    printf("DATA RECEIVED : %s\n",buffer);
    printf("Enter MSG : ");
    scanf("%s",buffer);

    send(newSocket,buffer,sizeof(buffer),0);
    return 0;


}