#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <string.h>
#include <fcntl.h>

extern int errno;

#define PORT_NUMBER 5500

int main( argc, argv )
int argc; char **argv;
{
  struct sockaddr_in sin_x;
  int    SizeSin_x;
  char   Buf[128];
  int    sd, sn, n;
  int    InitServer( );
  unsigned char *Ipa;

  if( argc != 2 ){
    printf("Uporaba: %s ImePostaje\n", argv[0]);
    exit( 1 );
  }
  if( (sd = InitServer( argv[1] )) < 0){
    perror("Napaka: "); exit( 1 );
  }
  listen( sd, 5 );
  alarm( 60 ); /* koncaj po eni minuti */
  while( 1 ){
    bzero((char *)&sin_x,sizeof(sin_x));
    SizeSin_x = sizeof(sin_x);
    if( (sn = accept(sd, (struct sockaddr_in *)&sin_x, &SizeSin_x)) < 0){
      perror("Napaka: "); exit( 2 ); 
    }
    /* zveza je vzpostavljena, ustvari strezni proces */
    if( fork() == 0 ){
      Ipa = (unsigned char *)&sin_x.sin_addr;
      printf("Zveza z %u.%u.%u.%u  je vzpostavljena\n", Ipa[0],Ipa[1],Ipa[2],Ipa[3]);
      while( (n = read( sn, Buf, sizeof( Buf ))) > 0 ){
	Buf[n] = 0;
	printf( "%s\n", Buf );
      }
      printf("Odjemalec je prekinil zvezo\n");
      exit( 0 );
    }
  }
}

int InitServer( host )
char *host;
{
  struct sockaddr_in sin_x;
  struct hostent     *hp_x;
  int sd;
  unsigned char *Nas;

  if( (hp_x=gethostbyname(host)) == NULL) return( -1 );
  bzero((char *)&sin_x,sizeof(sin_x));
  bcopy(hp_x->h_addr,(char *)&sin_x.sin_addr,hp_x->h_length);
  sin_x.sin_family  = hp_x->h_addrtype;
  sin_x.sin_port    = PORT_NUMBER;

  printf("Ime: %s,  ", hp_x -> h_name);
  Nas = (unsigned char *)(hp_x -> h_addr);
  printf("Naslov: %u.%u.%u.%u\n", *Nas, *(Nas+1), *(Nas+2), *(Nas+3));

  if( (sd = socket(AF_INET,SOCK_STREAM,0)) < 0 ) return( -2 );
  if( bind(sd, (struct sockaddr_in *)&sin_x, sizeof( sin_x )) < 0) return( -3 );
  return( sd );
}