Fehler gegen sendto() zu andere server, den mit UDP socket verbindet ist

[B. S. N. (bs_n)]

Hallo

Mein Programm kann nicht die erhaltene nachricht von ein Client zu 
anderen Server weiter schicken. Sie sind mit der UDP socket verbindet. 
Der code lautet wie es:

//Main SERVER
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <sys/select.h>//use select() for multiplexing
#include <sys/fcntl.h> // for non-blocking

#define MAX_LENGTH 100000
#define PORT 1901

/* Select() params
 * int select(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout);
 * FD_SET(int fd, fd_set *set);
 * FD_CLR(int fd, fd_set *set);
 * FD_ISSET(int fd, fd_set *set);
 * FD_ZERO(fd_set *set);
*/

void error(char *message)
{
    perror(message);
    exit(1);
}

int main()
{

  // select parameters declared
  fd_set original_socket;
  fd_set original_stdin;
  fd_set readfds;
  fd_set writefds;
  struct timeval tv;
  int numfd, numfd2;

  // socket parameters declared
  int socket_fd_ob, socket_fd_hm;
  int bytes_read, bytes_sent;
  char address_length, address_length2;
  char recieve_data[MAX_LENGTH];
  char send_data[MAX_LENGTH];
  struct sockaddr_in server_address_ob, server_address_hm, client_address;
  int z = 0;

  //Socket creation done separately for both OB and HM communications
  if ((socket_fd_ob = socket(AF_INET, SOCK_DGRAM, 0)) == -1) 
  {
      error("socket()");
  }
  if ((socket_fd_hm = socket(AF_INET, SOCK_DGRAM, 0)) == -1) 
  {
      error("socket()");
  }

  
  fcntl(socket_fd_ob, F_SETFL, O_NONBLOCK); //set socket to non-blocking
  fcntl(socket_fd_hm, F_SETFL, O_NONBLOCK); //set socket to non-blocking

  // clear the set ahead of time
  FD_ZERO(&original_socket);
  FD_ZERO(&original_stdin);
  FD_ZERO(&readfds);
  FD_ZERO(&writefds);
  
  // add our descriptors to the set (0 - stands for STDIN)
  FD_SET(socket_fd_ob, &original_socket);//instead of 0 put socket_fd_ob
  FD_SET(socket_fd_ob, &readfds);
  FD_SET(0,&original_stdin);
  FD_SET(0, &writefds);

  // since we got s2 second, it's the "greater", so we use that for
  // the n param in select()
  numfd  = socket_fd_ob + 1;
  numfd2 = socket_fd_hm + 1;
  

  // wait until either socket has data ready to be recv()d (timeout 10.5 secs)
  tv.tv_sec = 1;
  tv.tv_usec = 500000;

  server_address_ob.sin_family = AF_INET;
  server_address_ob.sin_port = htons(1901);
  server_address_ob.sin_addr.s_addr = inet_addr("127.0.0.3");
  bzero(&(server_address_ob.sin_zero),sizeof(server_address_ob));

  server_address_hm.sin_family = AF_INET;
  server_address_hm.sin_port = htons(1901);
  server_address_hm.sin_addr.s_addr = inet_addr("127.0.0.1");
  bzero(&(server_address_ob.sin_zero),sizeof(server_address_hm));

  // Bind socket to the particular addresses

  if (bind(socket_fd_ob,(struct sockaddr *)&server_address_ob, sizeof(struct sockaddr)) == -1)
  {
      error("bind()");
  }

  if (bind(socket_fd_hm,(struct sockaddr *)&server_address_hm, sizeof(struct sockaddr)) == -1)
  {
      error("bind()");
  }

  address_length  = sizeof(struct sockaddr);
  address_length2 = sizeof(struct sockaddr);

  printf("\nMain server waiting for client to respond...\n");
  fflush(stdout);
  
  while (1)
  {
    readfds = original_socket;
    writefds = original_stdin;//problem
    int recieve = select(numfd, &readfds, &writefds,/*NULL,*/ NULL, &tv);
    int sent    = select(numfd2, &readfds, &writefds,/*NULL,*/ NULL, &tv);

    if (recieve == -1 || sent == -1) 
    {
      perror("select"); // error occurred in select()
    } 
    else if (recieve == 0 || sent == 0) 
    {
      printf("Timeout occurred!  No data after 1.5 seconds.\n");
    } 
    else 
    {
        // one or both of the descriptors have data
        if (FD_ISSET(socket_fd_ob, &readfds)) //if set to read
        { 
          FD_CLR(socket_fd_ob, &readfds);
          bytes_read = recvfrom(socket_fd_ob,recieve_data,MAX_LENGTH,0,(struct sockaddr *)&server_address_hm, &address_length); 
      
   for (z = 0; z < bytes_read; ++z) {
   FD_ISSET(socket_fd_hm, &writefds);
          FD_CLR(socket_fd_hm, &writefds);
          //recvfrom speech recognition client and decide what to send to HM accordingly..
          send_data[bytes_read] = recieve_data[bytes_read];
          //block call, will wait till client enters something, before proceeding
          //send the corresponding to HM
          bytes_sent = sendto(socket_fd_hm,send_data,strlen(send_data)+1,0,(struct sockaddr *)&server_address_hm, &address_length2); 
          fflush(stdout);
      }                  
          recieve_data[bytes_read] = '\0'; //add null to the end of the buffer
          send_data[bytes_read] = '\0'; //add null to the end of the buffer
          
          printf("\n(%s , %d) rcvd: %02x\n",inet_ntoa(server_address_hm.sin_addr),ntohs(server_address_hm.sin_port),recieve_data);
          printf("\n(%s , %d) sent: %02x\n",inet_ntoa(server_address_hm.sin_addr),ntohs(server_address_hm.sin_port),send_data);
        }




    } //end else
  }//end while

  close (socket_fd_ob);
  return 0;
}

Ich kann es mit dem WIRESHARK prüfen dass es die Nachrichten von 
127.0.0.2 immer kreigst, aber er könnte nicht zu 127.0.0.1 weitere 
schicken. Könnten sie bitte vorschlagen wie ich es lösen könnte.

Danke schön.

[jonas biensack (Gast)]

127.0.0.1 is the local host adress. You need to use another ip.

kind regards jonas