Re: [Bug-gnulib] getpass echoes on many systems

[Bruno Haible]

Larry Jones wrote:
> We just had a bug report on the newly-released CVS 1.11.7 that passwords
> were getting echoed, not while entering them, but after hitting return.
> This is due to a bug in getpass.c.  According to the C standard, input
> may not be followed by output on the same stream without an intervening
> call to a file positioning function.  Here's a patch:

Thanks a lot. I've committed your fix, with an extended comment in the
source code.

> +#ifndef SEEK_CUR
> +#define SEEK_CUR 1
> +#endif

I've replaced this with #include <fcntl.h>, Should be sufficient for those
systems that don't define SEEK_CUR in <stdio.h>, I hope?

Bruno


*** getpass.c   9 Jul 2003 22:48:53 -0000       1.4
--- getpass.c   1 Oct 2003 11:11:02 -0000       1.5
***************
*** 1,4 ****
! /* Copyright (C) 1992,93,94,95,96,97,98,99,2000, 2001 Free Software 
Foundation, Inc.
     This file is part of the GNU C Library.
  
     This program is free software; you can redistribute it and/or modify
--- 1,4 ----
! /* Copyright (C) 1992-2001, 2003 Free Software Foundation, Inc.
     This file is part of the GNU C Library.
  
     This program is free software; you can redistribute it and/or modify
***************
*** 22,27 ****
--- 22,28 ----
  #include <stdio.h>
  #include <termios.h>
  #include <unistd.h>
+ #include <fcntl.h>
  #include "getline.h"
  #include "unlocked-io.h"
  
***************
*** 84,91 ****
          /* Remove the newline.  */
          buf[nread - 1] = '\0';
          if (tty_changed)
!           /* Write the newline that was not echoed.  */
!           putc ('\n', out);
        }
      }
  
--- 85,102 ----
          /* Remove the newline.  */
          buf[nread - 1] = '\0';
          if (tty_changed)
!           {
!             /* Write the newline that was not echoed.
!                But before doing that, do a no-op fseek.  According to the C
!                standard, input may not be followed by output on the same
!                stream without an intervening call to a file positioning
!                function.  Without this fseek() call, on Solaris, HP-UX,
!                AIX, OSF/1, the previous input gets echoed, whereas on IRIX,
!                the following newline is not output as it should.  */
!             if (out == in)
!               fseek (out, 0, SEEK_CUR);
!             putc ('\n', out);
!           }
        }
      }