File Server Help

This is a discussion on File Server Help within the C Programming forums, part of the General Programming Boards category; Suggestions: 1. Make sure sendfile is being called. (Put some test output at the top of the function and make ...

  1. #46
    and the Hat of Guessing tabstop's Avatar
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    Suggestions:
    1. Make sure sendfile is being called. (Put some test output at the top of the function and make sure you do fflush(stdout).)
    2. Did you fix your send commands in sendfile? (I seem to recall that you had the same errors there as elsewhere -- using a raw number as the second argument instead of a pointer, etc.)

  2. #47
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    Testing on my code i found this..
    Code:
    if(!connect(sock, (struct sockaddr *)&dest_addr, sizeof(dest_addr))) { 
    printf("error?");
    exit(1);
    }
    Made the client crash, don't know why, because it connected to the server, removing the exit(1); the client succesfully runned the function, but there's a problem with the server, it's not comparing the passwd string..

    Code:
    int passwdcheck(int *sock) {
    char password[]="lol";
    char i;
    char buff[30];
    recv(*sock, buff, sizeof(buff), 0);
    printf("Client Passwd: %s and lenght: %i\n", buff, strlen(buff));
    printf("Server Passwd: %s and lenght: %i \n", password, strlen(password));
    if(!strcmp(password, buff)) {
    i = 0;
    send(*sock, &i, sizeof(i), 0);
    return 0;
    }
    else {
    i = 1;
    send(*sock, &i, sizeof(i), 0);
    return 1;
    }
    }

  3. #48
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    Code:
    printf("Client Passwd: %s and lenght: %i\n", buff, strlen(buff));
    printf("Server Passwd: %s and lenght: %i \n", password, strlen(password));
    strlen returns size_t, not int. If you're using C99, use %zu, otherwise, use %lu and cast the result of strlen to unsigned long.

    http://ubuntuforums.org/showthread.php?t=697074

  4. #49
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    I used %lu and it returned

    Client Passwd: lol and lenght: 11
    Server Passwd: lol and lenght: 3

    What can I do to correct that? and why does the client password has 11 as lenght? =S

  5. #50
    CSharpener vart's Avatar
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    Are you sending the nul-terminator?

    check the return value of recv as well
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  6. #51
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    I missed something but I've corrected it, and its more confusing now

    In the client
    Code:
    unsigned long sending;
    sending=send(sock, password, strlen(password)+1, 0);
    printf("Sending: %lu \n", sending);
    int intbuf;
    recv(sock, intbuf, sizeof(intbuf), 0);
    printf("Recibi: %i \n", intbuf);
    int buf2;
    //password check has been removed due it always says its correct 
    printf("Password ok..\n");
    It's printing
    Sending: 4
    Recibi: -1208592900
    Password ok..
    And the server
    Code:
    unsigned long passlen;
    unsigned long serverpasslen;
    unsigned long recivi;
    serverpasslen = strlen(password);
    
    recivi=recv(*sock, buff, sizeof(buff), 0);
    passlen = strlen(buff);
    printf("Client Passwd: %s and lenght: %lu\n", buff, passlen);
    printf("Recivi: %lu \n", recivi);
    printf("Server Passwd: %s and lenght: %lu \n", password, serverpasslen);
    printf("Que da el cmp: %i \n", strcmp(password, buff));
    It's printing
    Client Passwd: lol and lenght: 3
    Recivi: 4
    Server Passwd: lol and lenght: 3
    Que da el cmp: 0
    Password incorrecta

  7. #52
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    Code:
    int intbuf;
    recv(sock, intbuf, sizeof(intbuf), 0);
    What is wrong with this?

  8. #53
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    I really don't know, but what about the strcmp?
    Code:
    if(!strcmp(password, buff)) {
    i = 0;
    send(*sock, &i, sizeof(i), 0);
    return 0;
    }
    else {
    i = 1;
    send(*sock, &i, sizeof(i), 0);
    return 1;
    }
    }

  9. #54
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    Check your man pages for the parameter types of recv and the return values of strcmp.

  10. #55
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    The strcmp() function compares the two strings s1 and s2. It returns
    an integer less than, equal to, or greater than zero if s1 is found,
    respectively, to be less than, to match, or be greater than s2.
    Mmm.. I see.. it should return 0 if the two words matches, and 0 it's false, so I've a mistake with the if sentence

  11. #56
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    Well.. now I'm having a problem with the select, it's like its not recv and sending all the things the function on the select is asking for, it's like if the select were catching all the information sended..

  12. #57
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    Post your code please.

  13. #58
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    This is the select part
    Code:
    FD_SET(listener, &master);
    /* cantidad de sock */
    fdmax = listener;
    /* loop */
    for(;;) {
    /* copiar */
    read_fds = master;
    /* comienza select */
      if(select(fdmax+1, &read_fds, NULL, NULL, NULL) == -1) {
      perror("Server-select() error lol!");
      exit(1);
      }
      printf("Select starteado\n");
      for(i = 0; i <= fdmax; i++) {
        if(FD_ISSET(i, &read_fds)) {
          if(i == listener) { /* nueva conexion */
            addrlen = sizeof(clientaddr);
            if((newfd = accept(listener, (struct sockaddr *)&clientaddr, &addrlen)) == -1) {
              perror("Server-accept() error lol!");
            }
            printf("Nueva conexion.. testeando pass\n");
          if(passwdcheck(&newfd) == 1) {
            FD_SET(newfd, &master);
            printf("Password correcta\n");
            if(newfd > fdmax){ /* keep track of the maximum */
              fdmax = newfd;
            }
          }
          else {
            close(newfd);
            printf("Password incorrecta\n");
          }
        }
        else {
          if((nbytes = recv(i, buf, sizeof(buf), 0)) <= 0) { /* se encarga de conexiones existentes */
            if(nbytes == 0) {
              close(i);
              FD_CLR(i, &master);
              printf("Conexion perdida\n");
            }
            else {
              recievefile(&i);
            }
          }
        }
    
      }
    }

  14. #59
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    Can you attach both files?

  15. #60
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    Sure, what about using fork() ?
    Attached Files Attached Files
    Last edited by lautarox; 09-12-2008 at 01:35 PM.

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