#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <stdio.h>
#include <sys/timeb.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <signal.h>

#include <errno.h>

#include <stdlib.h>
#include <unistd.h>

#define DEFAULTPORT 1515

#define SUM 0
#define PRODUCT 1




#define TRUE (1==1)
#define FALSE (1==0)

int log_is_active=FALSE;

int pid_server;
int	pid1,pid2;

void sigusr_handler(int signo)
{
  if(getpid() == pid_server)
    {
      if (pid1 > 0)
	kill(pid1,signo);
      if(pid2>0)
	kill(pid2,signo);
    }

  if(signo == SIGUSR1)
    {
      log_is_active=TRUE;
      printf("Log is now active\n");
    }
  else
  if(signo == SIGUSR2)
    {
    log_is_active=FALSE;
    printf("Log is now inactive\n");
    }
  

}



main(int argc,char *argv[])
{
  int	length;
  struct 	sockaddr_in 	server1,server2,client;
  fd_set sock_fdset;
  int sock1,sock2;
  int	msgsock1,msgsock2,rval,i;
  struct sigaction sig;
  char line[256],answer[256];
  int op1,op2;
  int somma, prodotto;



 sig.sa_handler = sigusr_handler;
 sigemptyset(&sig.sa_mask);
 sig.sa_flags=SA_RESTART;

 sigaction(SIGUSR1,&sig,NULL);
 sigaction(SIGUSR2,&sig,NULL);


  /* Vanno utilizzate due socket ognuna con il proprio indirizzo quindi con porte diverse */


  pid_server= getpid();
  printf("Server PID=%d\n",pid_server);




  /* Crea la  socket STREAM 1 e STREAM 2*/
  sock1=socket(AF_INET,SOCK_STREAM,0);
  if(sock1<0)
    {   perror("opening stream socket 1");
      exit(1);
    }

  sock2=socket(AF_INET,SOCK_STREAM,0);
  if(sock2<0)
    {   perror("opening stream socket 2");
      exit(1);
    }



  /* Utilizzo della wildcard per accettare le connessioni da ogni client */
  server1.sin_family =  AF_INET;
  server1.sin_addr.s_addr= INADDR_ANY;
  server1.sin_port = htons(1520);
  if (bind(sock1,(struct sockaddr *)&server1,sizeof server1)<0)
    {
      perror("binding stream socket");
      exit(1);
    }
  server2.sin_family =  AF_INET;
  server2.sin_addr.s_addr= INADDR_ANY;
  server2.sin_port = htons(1521);
  if (bind(sock2,(struct sockaddr *)&server2,sizeof server2)<0)
    {
      perror("binding stream socket");
      exit(1);
    }


  length= sizeof server1;
  if(getsockname(sock1,(struct sockaddr *)&server1,&length)<0)
    {
      perror("getting socket name");
      exit(1);
    }
  printf("Socket 1 port #%d\n",ntohs(server1.sin_port));
  length= sizeof server2;
  if(getsockname(sock2,(struct sockaddr *)&server2,&length)<0)
    {
      perror("getting socket name");
      exit(1);
    }
  printf("Socket 2 port #%d\n",ntohs(server2.sin_port));



  listen(sock1,4);

  listen(sock2,4);
  
  do 
    {
      FD_ZERO(&sock_fdset);
      FD_SET(sock1,&sock_fdset);
      FD_SET(sock2,&sock_fdset);
      
      select(sock2+1,&sock_fdset, NULL, NULL, NULL);
      
    if(FD_ISSET(sock1, &sock_fdset))
      {
	msgsock1 = accept(sock1, (struct sockaddr *)&client, &length ) ;
	  
	  if((pid1=fork())==0)
	    {
	      close(sock1);
	      read(msgsock1, line, sizeof(line));
	      sscanf(line, "%d %d",&op1,&op2);
	      somma = op1 + op2 ;
	      
	      if(log_is_active)
		printf("%d = %d + %d\n",somma,op1,op2);
	      
	      sprintf(answer,"%d\n",somma);
	      
	      write(msgsock1, answer, strlen(answer)+1);
	      close(msgsock1);
	      exit(0);	      
	    }
	  else
	    {
	      close(msgsock1);
	    }

	
      }
    
    if(FD_ISSET(sock2, &sock_fdset))
      {
	msgsock2 = accept(sock2, (struct sockaddr *)&client, &length );
	     
	if((pid2=fork())==0)
	    {
	      close(sock2);
	      read(msgsock2, line, sizeof(line));
	      sscanf(line, "%d %d",&op1,&op2);
	      prodotto = op1 * op2 ;
	      sprintf(answer,"%d\n",prodotto);
	      
	      
	      if(log_is_active)
		printf("%d = %d * %d\n",prodotto,op1,op2);
	      
	      
	      write(msgsock2, answer, strlen(answer)+1);
	      close(msgsock2);

	      exit(0);
	      
	    }
	     else
	       {
		 close(msgsock2);
	       }

	     
      }
    
    
    } while(1);
}