Connect to two servers with all my client

See more:

C

Linux

Hello everyone, I am doing a project in the programming language c.
I created a chat that clients can talk to each other using the server.
I want to connect all the clients to another server and when they leave one server they will go straight to the other server, which means I wanted them to log in with a certain condition to the other server (say with a certain if).
The problem is that I really do not know how to do it I would be very happy to help create the second server. And how exactly do I run the second server in Linux.
Many thanks to the helpers.
mor levi

What I have tried:

my client code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <sys types.h="">
#include <sys socket.h="">
#include <netinet in.h="">
#include <arpa inet.h="">
#include <pthread.h>


#define MAX_CLIENTS 100
#define BUFFER_SZ 2048
#define name_len 32
// Global variables
volatile sig_atomic_t flag = 0;
volatile sig_atomic_t playflag = 0;
int sockfd = 0;
char name[name_len];

//overwriting the characters which have already been displayed by the terminal
void str_overwrite_stdout()
{
  printf("%s", ">");
  fflush(stdout);
  //sleep(1);//added
}


void str_trim_lf (char* arr, int length)
{
  int i;
  for (i = 0; i < length; i++)
  { // trim \n
    if (arr[i] == '\n')
    {
      arr[i] = '\0';
      break;
    }
  }
}


void catch_ctrl_c_and_exit(int sig)
{
    flag = 1;
}

void recv_msg_handler()
{
char message[BUFFER_SZ] = {};
  while (1)
  {
int receive = recv(sockfd, message, BUFFER_SZ, 0);
    if (receive > 0)
    {
      printf("%s", message);
        str_overwrite_stdout();
    } else if (receive == 0)
    {
break;
    } /*else {
// -1 }*/
bzero(message, sizeof(message));
  }
}


void send_msg_handler()
{
  char buffer[BUFFER_SZ] = {};
  char message[BUFFER_SZ + name_len+2] = {};

  while(1)
   {
    str_overwrite_stdout();
    fgets(buffer, BUFFER_SZ, stdin);
    str_trim_lf(buffer, BUFFER_SZ);

if(playflag ==0);
        {
/*////////////////////////////////////////////////////////////////////uselesssssss

        if(strcmp(buffer,"LIST") == 0)
        {
            int l = 0;
            for(int i = 0 ; i < clientCount ; i ++)
            {
                if(i != index)
                    l += snprintf(output + l,1024,"Client %d is at socket %d.\n",i +         1,Client[i].sockID);

            }
            send(clientSocket,output,1024,0);
            continue;

        }

*/



     if(strcmp(buffer,"ONLINE") == 0)
     {
 sprintf(message, "%s:%s\n", name, buffer);
      send(sockfd, message, strlen(message), 0);
    }


  else  if (strcmp(buffer, "exit") == 0)
    {
break;
    }
   
     /*else if (strcmp(buffer, "GAME") == 0)
        {
            sprintf(message, "%s:%s\n", name, "game begun \n game's rules:\n 1>one of the players gets to be a murdrer \n 2>allthe other players get to be the villegers \n 3>the villegers need idntify who is the murderer befor the the time ends\n");
            send(sockfd, message, strlen(message), 0);
            printf("game begun \n");
            printf("game's rules:\n 1>one of the players gets to be a murdrer \n 2>allthe other players get to be the villegers \n 3>the villegers need idntify who is the murderer befor the the time ends \n ");
        }
    */
   
    else {
      sprintf(message, "%s:%s\n", name, buffer);
      if(strcmp(buffer, "GAME")== 0 )
      {
      send(sockfd, buffer, strlen(buffer), 0);
      printf("game's rules:\n 1>one of the players gets to be a murdrer \n 2>allthe other players get to be the villegers \n 3>the villegers need idntify who is the murderer befor the the time ends \n ");
      }
     else send(sockfd, message, strlen(message), 0);
           }
     }
    bzero(buffer, BUFFER_SZ);
    bzero(message, BUFFER_SZ + name_len);
   
   }
  catch_ctrl_c_and_exit(2);
}




//main
int main(int argc, char **argv)
{

/*
  char massage[BUFFER_SZ];
    int numbytes;

*/
if(argc != 2)
{
printf("Usage: %s <port>\n", argv[0]);
return EXIT_FAILURE;
}

char *ip = "127.0.0.1";
int port = atoi(argv[1]);

signal(SIGINT, catch_ctrl_c_and_exit);

printf("Please enter your name: ");
  fgets(name, name_len, stdin);
  str_trim_lf(name, strlen(name));

if (strlen(name) > name_len-1 || strlen(name) < 2)
{
printf("Name must be less than 32 and more than 2 characters.\n");
return EXIT_FAILURE;
}

struct sockaddr_in server_addr;

//Socket settings
sockfd = socket(AF_INET, SOCK_STREAM, 0);//make socket  
  server_addr.sin_family = AF_INET;//ADDED - this reserts the socket parameters
  server_addr.sin_addr.s_addr = inet_addr(ip);
  server_addr.sin_port = htons(port);//"host to network,short" standart byte order synchrenize


// Connect to Server
  int err = connect(sockfd, (struct sockaddr *)&server_addr, sizeof(server_addr));//try to connerct to server
  if (err == -1) //the error worning (could be done with if(... <0 then error without the int
  {
printf("ERROR: connect\n");
return EXIT_FAILURE;
}
// Send name
send(sockfd, name, 32, 0);

printf("elcome to mor-yael-sean (mys) chat  \n");
pthread_t send_msg_thread;
  if(pthread_create(&send_msg_thread, NULL, (void *) send_msg_handler, NULL) != 0)
  {
printf("ERROR: pthread\n");
    return EXIT_FAILURE;
}

pthread_t recv_msg_thread;
  if(pthread_create(&recv_msg_thread, NULL, (void *) recv_msg_handler, NULL) != 0)
  {
printf("ERROR: pthread\n");
return EXIT_FAILURE;
}

while (1)
{
if(flag)
{
printf("\nBye\n");
break;
    }
}

close(sockfd);

return EXIT_SUCCESS;
}

my server code:

<pre>#include <math.h> 
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <pthread.h>
#include <netinet in.h="">
#include <sys socket.h="">
#include <sys types.h="">
#include <arpa inet.h="">
#include <errno.h>
#include <signal.h>
#include <time.h> //time functions
#include <string.h>
#include <math.h>
//#include <dos.h>
#define MAX_CLIENTS 100
#define BUFFER_SZ 2048
#define name_len 18
static _Atomic unsigned int cli_count=0;
static int uid=10;

//Client structure
typedef struct{
struct sockaddr_in address;//adress
int sockfd;//socket field descriptor
int uid; //user id
char name[name_len];//user's name
int role; // (1. murderur) (2. villeger) (3.dead)
} client_t;

client_t *clients[MAX_CLIENTS];

pthread_mutex_t clients_mutex = PTHREAD_MUTEX_INITIALIZER;// this mutex we have to require when we are goind to transfer to send the massage between the clients
       
void delay(int number_of_seconds)
{
    // Converting time into milli_seconds
    int milli_seconds = 1000 * number_of_seconds;
 
    // Storing start time
    clock_t start_time = clock();
 
    // looping till required time is not achieved
    while (clock() < start_time + milli_seconds);
   
   
//delay(pow(i,2));//when we want to use it this is the code
}
   
   
   


void str_overwrite_stdout()
{
    printf("\r%s", " > ");
    fflush(stdout);
}

void str_trim_lf (char* arr, int length)
{
  int i;
  for (i = 0; i < length; i++)
{ // trim \n
    if (arr[i] == '\n')
{
  arr[i] = '\0';
      break;
    }
  }
}

//Add clients to queue
void queue_add(client_t *cl)
{
pthread_mutex_lock(&clients_mutex);

for(int i=0; i < MAX_CLIENTS; ++i)
{
if(!clients[i])
{
clients[i] = cl;
break;
}
}

pthread_mutex_unlock(&clients_mutex);
}

//Remove clients to queue
//that program know how to remove that client daddy, use the uniq id that all client have
void queue_remove(int uid)
{
pthread_mutex_lock(&clients_mutex);
for(int i=0; i < MAX_CLIENTS; ++i)
{
if(clients[i])
{
if(clients[i]->uid == uid)
{
clients[i] = NULL;
break;
}
}
}

pthread_mutex_unlock(&clients_mutex);
}

//how much clients are online right now
/*void counter_online()
{
cnt=0;
pthread_mutex_lock(&clients_mutex);
for(int i=0; i < MAX_CLIENTS; ++i)
{
if(clients[i])
cnt++;

}

pthread_mutex_unlock(&clients_mutex);
return cnt;
}

*/
// Send message to all clients except sender
void send_message(char *s, int uid)
{
pthread_mutex_lock(&clients_mutex);

for(int i=0; i<max_clients; ++i)
{
if(clients[i])
{
if(clients[i]-="">uid != uid)
{
if(write(clients[i]->sockfd, s, strlen(s)) < 0)
{
perror("ERROR: write to descriptor failed");
break;
}
}
}
}

pthread_mutex_unlock(&clients_mutex);
}

//Handle all communication with the client
void *handle_client(void *arg)
{
int counter;
char buff_out[BUFFER_SZ];
char name[32];
int leave_flag = 0;//indicate that whether the client is conected or not or there is an error
cli_count++;
client_t *cli = (client_t *)arg;

// Name
if(recv(cli->sockfd, name, name_len, 0) <= 0 || strlen(name) <  2 || strlen(name) >= 32-1)
{
printf("Didn't enter the name!\n");
leave_flag = 1;
} else{
strcpy(cli->name, name);
sprintf(buff_out, "%s has joined\n", cli->name);
printf("%s", buff_out);
send_message(buff_out, cli->uid);
              }

bzero(buff_out, BUFFER_SZ);

while(1)
{
if (leave_flag)
{
break;
          }
/* if(send(clients[1]->sockfd, "Wellcome\n", 9, 0) == -1)  
       perror("send");
       */
int receive = recv(cli->sockfd, buff_out, BUFFER_SZ, 0);
if (receive > 0)
{
if(strlen(buff_out) > 0)
{
//send_message(buff_out, cli->uid);
if (strcmp(buff_out, "GAME") == 0)
{
memcpy(buff_out,"game's rules:\n 1>one of the players gets to be a murdrer \n 2>allthe other players get to be the villegers \n 3>the villegers need idntify who is the murderer befor the the time ends \n ",strlen("game's rules:\n 1>one of the players gets to be a murdrer \n 2>allthe other players get to be the villegers \n 3>the villegers need idntify who is the murderer befor the the time ends \n ")+1);
send_message(buff_out, cli->uid);
//counter=counter_online();
char scount[5];
sprintf(scount,"%d",cli_count);
if(send(cli->sockfd, scount,3, 0) == -1)  
               perror("send");
}
else{
send_message(buff_out, cli->uid);
str_trim_lf(buff_out, strlen(buff_out));
//printf("%s -> %s\n", buff_out, cli->name);
printf("%s \n", buff_out);
   }
}
}/*else if (strcmp(buff_out,"ONLINE")==0)

queue_print();

*/
else if (receive == 0 || strcmp(buff_out, "exit") == 0)
{
sprintf(buff_out, "%s has left\n", cli->name);
printf("%s", buff_out);
send_message(buff_out, cli->uid);
leave_flag = 1;
       }
 /*      else if(receive == 0 || strcmp(buff_out, "GAME") == 0)
       
            {
            int cnt=0;
            for(int i=0; i < MAX_CLIENTS; ++i)
            {
           
                if(!clients[i])
               {
                    break;
                  }
           
           
            }
       
        {int count=0;
          for(int i=0; i < MAX_CLIENTS; ++i)
           {
               if (count==0)    
               {
               
               }
            clients[i] =(rand() % (2 - 1 + 1)) + 1;
           
            else
           clients[i]=1;
       }
       
        }
*/
  else {
printf("ERROR: -1\n");
leave_flag = 1;
}

bzero(buff_out, BUFFER_SZ);
}

//Delete client from queue and yield thread
close(cli->sockfd);
  queue_remove(cli->uid);
  free(cli);
  cli_count--;
  pthread_detach(pthread_self());

return NULL;
}



void print_client_addr(struct sockaddr_in addr)
{
    printf("%d.%d.%d.%d",
(addr.sin_addr.s_addr & 0xff),
        (addr.sin_addr.s_addr & 0xff00) >> 8,
        (addr.sin_addr.s_addr & 0xff0000) >> 16,
        (addr.sin_addr.s_addr & 0xff000000) >> 24);
}

int main(int argc, char **argv)
{
if(argc != 2)
{
printf("Usage: %s <port>\n", argv[0]);
return EXIT_FAILURE;
}

char *ip = "127.0.0.1";
int port = atoi(argv[1]);
//int port2 = atoi(argv[2]);
int option = 1;
int listenfd = 0, connfd = 0;
//int listenfd2 = 0, connfd2 = 0;
  struct sockaddr_in serv_addr;
  struct sockaddr_in cli_addr;
  pthread_t tid;

//Socket settings
listenfd = socket(AF_INET, SOCK_STREAM, 0);
serv_addr.sin_family = AF_INET;
  serv_addr.sin_addr.s_addr = inet_addr(ip);
  serv_addr.sin_port = htons(port);
  //serv_addr.sin_port = htons(port2);

//signals
signal(SIGPIPE, SIG_IGN);

if(setsockopt(listenfd, SOL_SOCKET,(SO_REUSEPORT | SO_REUSEADDR),(char*)&option,sizeof(option)) < 0)
{
perror("ERROR: setsockopt failed");
    return EXIT_FAILURE;
}

//Bind
  if(bind(listenfd, (struct sockaddr*)&serv_addr, sizeof(serv_addr)) < 0)
{
           perror("ERROR: Socket binding failed");
           return EXIT_FAILURE;
  }

//Listen
  if (listen(listenfd, 10) < 0)
{
    perror("ERROR: Socket listening failed");
    return EXIT_FAILURE;
}
printf("this is our's chatroom\n");

while(1)
{
/*while(num)
    {
       cnt =pow(2,2)*1000;
       delay(cnt);//pow cnt =1000
       num --;
         printf("shss");
       
    }
    */




//accept the conect with client
socklen_t clilen = sizeof(cli_addr);
connfd = accept(listenfd, (struct sockaddr*)&cli_addr, &clilen);

//Check if max clients is reached
if((cli_count + 1) == MAX_CLIENTS)
{
printf("Max clients reached therfore Rejected: ");
print_client_addr(cli_addr);
printf(":%d\n", cli_addr.sin_port);//print the client addres that rejected
close(connfd);
continue;
}




//Client settings
client_t *cli = (client_t *)malloc(sizeof(client_t));
cli->address = cli_addr;
cli->sockfd = connfd;
cli->uid = uid++;

//Add client to the queue and fork thread
queue_add(cli);
pthread_create(&tid, NULL, &handle_client, (void*)cli);

//Reduce CPU usage
sleep(1);
}

return EXIT_SUCCESS;
}