Masking input

This is a discussion on Masking input within the C++ Programming forums, part of the General Programming Boards category; How would one go about masking an input... Like when entering passwords and pins and such? Running Windows Vista, making ...

  1. #1
    Registered User bradszy's Avatar
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    Masking input

    How would one go about masking an input... Like when entering passwords and pins and such? Running Windows Vista, making a Console app. Thanks guys.

  2. #2
    CSharpener vart's Avatar
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    Quote Originally Posted by bradszy View Post
    How would one go about masking an input... Like when entering passwords and pins and such? Running Windows Vista, making a Console app. Thanks guys.
    You probably think you are the first who is asking this question...

    Search forum for similar posts, read the answers, write your code and ask question about problems you encountered

    For the start - read thsi http://faq.cprogramming.com/cgi-bin/...&id=1043284392

    It explains how you can read an input before user press enter
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  3. #3
    Registered User bradszy's Avatar
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    getch()

    I'm having some trouble using it. Here's my code:
    Code:
    #include <iostream>
    #include <cstdlib>
    #include <windows.h>
    #include <winable.h>
    #include <string>
    #include <winuser.h>
    #include <stdio.h> 
    #include <conio.h> 
    #include <ctype.h> 
    
    
    using namespace std;
    int main(int argc, char *argv[])
    {
    int ch;
    int i = 0;
    char PROTECTEDLOL[12];
    char password[90];
    int SECRETANSWER;
    LOL:
    system("color fc");
    system("cls");
    
    puts ("What would you like to do?");
    puts ("Enter password");
    puts (" OR " );
    puts ("Press [2] To Exit" );
    fflush(stdout);
    
     while ((ch = getch()) != EOF 
              && ch != '\n' 
              && ch != '\r' 
              && i < sizeof(PROTECTEDLOL) - 1)
      {
        if (ch == '\b' && i > 0) 
        {
          printf("\b \b");
          fflush(stdout);
          i--;
          PROTECTEDLOL[i] = '\0';
        }
        else if (isalnum(ch))
        {
          putchar('*');
          PROTECTEDLOL[i++] = (char)ch;
        }
      }
    
    if (PROTECTEDLOL=="password")
    {
    	
    	puts ("Hi");
    }
    
    else if (PROTECTEDLOL=="2")
    {
         cout<<endl<<endl<<"Bye"<<endl;
         Sleep(3000);
         return 0;
         }
    	
        else
    	{
    		MessageBox(NULL, "Password is invalid", "Denied", 48 | 1);
    		MessageBox(NULL, "Access is denied", "Denied", 48 | 1);
    		goto LOL;
    	}
    	
    return 0;
    }
    It gives me my error EVERY time. I don't know how to make it work. Any help? Thanks.

  4. #4
    CSharpener vart's Avatar
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    conio and getch are for Borland compilers
    what compiler are you using?
    what is the error?
    The first 90% of a project takes 90% of the time,
    the last 10% takes the other 90% of the time.

  5. #5
    Registered User bradszy's Avatar
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    Dev-C++,
    And by 'my error' I'm refering to line 62, my 'else' statement.
    I've looked in Dev-C++'s 'include' directory, and conio.h is in there.
    Thanks to anyone that can help with my problem.

  6. #6
    ZuK
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    Code:
    if (PROTECTEDLOL=="password")
    This compares pointers -> will never be true
    use strcmp()
    Kurt

  7. #7
    Registered User bradszy's Avatar
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    Like:
    Code:
    strcmp(PROTECTEDLOL=="password");
    ?

  8. #8
    ZuK
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    more like
    Code:
    if ( strcmp(PROTECTEDLOL,"password") == 0 )
    or
    Code:
    if ( !strcmp(PROTECTEDLOL,"password"))
    Kurt

  9. #9
    Registered User bradszy's Avatar
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    Oh thankyou.

    EDIT:
    Code:
    #include <iostream>
    #include <cstdlib>
    #include <windows.h>
    #include <winable.h>
    #include <string>
    #include <winuser.h>
    #include <stdio.h> 
    #include <conio.h> 
    #include <ctype.h> 
    
    
    using namespace std;
    int main(int argc, char *argv[])
    {
    int ch;
    int i = 0;
    char PROTECTEDLOL[BUFSIZ];
    char password[BUFSIZ];
    int SECRETANSWER;
    LOL:
    system("color fc");
    system("cls");
    
    puts ("What would you like to do?");
    puts ("Enter password");
    puts (" OR " );
    puts ("Press [2] To Exit" );
    fflush(stdout);
    
     while ((ch = getch()) != EOF 
              && ch != '\n' 
              && ch != '\r' 
              && i < sizeof(PROTECTEDLOL) - 1)
      {
        if (ch == '\b' && i > 0) 
        {
          printf("\b \b");
          fflush(stdout);
          i--;
          PROTECTEDLOL[i] = '\0';
        }
        else if (isalnum(ch))
        {
          putchar('x');
          PROTECTEDLOL[i++] = (char)ch;
        }
      }
    
    if ( !strcmp(PROTECTEDLOL,"password"));
    {
    	
    	puts ("Hi");
    }
    
    else if ( !strcmp(PROTECTEDLOL,"2"))
    {
         cout<<endl<<endl<<"Bye"<<endl;
         Sleep(3000);
         return 0;
    }
    	
        else
    	{
    		MessageBox(NULL, "Password is invalid", "Denied", 48 | 1);
    		MessageBox(NULL, "Access is denied", "Denied", 48 | 1);
    		goto LOL;
    	}
    	
    return 0;
    }
    ERRORS:
    Code:
    55 C:\Users\bradszy\Desktop\Untitled1.cpp expected primary-expression before "else" 
    55 C:\Users\bradszy\Desktop\Untitled1.cpp expected `;' before "else" 
    62 C:\Users\bradszy\Desktop\Untitled1.cpp expected primary-expression before "else" 
    62 C:\Users\bradszy\Desktop\Untitled1.cpp expected `;' before "else"
    Last edited by bradszy; 02-23-2008 at 02:58 AM.

  10. #10
    ZuK
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    Code:
    if ( !strcmp(PROTECTEDLOL,"password"));  <<-- remove that semicolon

  11. #11
    Registered User bradszy's Avatar
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    Still says invalid password. This is interesting.

  12. #12
    ZuK
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    Quote Originally Posted by bradszy View Post
    Still says invalid password. This is interesting.
    Guess PROTECTEDLOL is not properly terminated
    try
    Code:
        else if (isalnum(ch))
        {
          putchar('x');
          PROTECTEDLOL[i++] = (char)ch;
          PROTECTEDLOL[i] = 0;
        }
    Kurt

  13. #13
    Registered User bradszy's Avatar
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    Thanks Kurt, you're pretty good at this eh? Worked perfectly. Thanks again, it's really appreciated.

  14. #14
    C++まいる!Cをこわせ! Elysia's Avatar
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    Another suggestion for you, in case you have time or is willing: http://cpwiki.sf.net/Indentation
    Good luck.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

  15. #15
    Registered User Codeplug's Avatar
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    I'm partial to this implementation - no particular reason
    Masking password input

    gg

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