Date: Thu, 31 Oct 1996 14:06:27 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Neil Jarvis <Neil DOT Jarvis AT proteon DOT com>
Cc: djgpp-workers AT delorie DOT com
Subject: Re: ar on networked drive
In-Reply-To: <9610301718.AA27269@leopard.proteon.com>
Message-Id: <Pine.SUN.3.91.961031135643.23595A-100000@is>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII


On Wed, 30 Oct 1996, Neil Jarvis wrote:

> I think the conversion test should be moved outside the first group of
> if/elses to catch all the cases of failure, where errno = ENMFILE.

Thanks for your clear diagnostics.  Please try the patch below and tell 
me if it works for you, so it could be used to fix the library and the 
executables in bnu27b.zip.

(If you have problems installing the patch, drop me a note and I will 
explain how to do it.)

> But
> I don't understand this routine, or why it is even looking at volume
> labels, so I am looking to the experts for a fix.

The reason is explained in the comments in the code fragment that you've 
posted.  We want `stat' to be able to return valid info when called on 
volume labels, since a volume label is a directory entry on MSDOS.  An 
early version of `stat' used to call `findfirst' just once with all the 
possible attributes, including FA_LABEL.  However, it turned out that 
some environments (and your NFS client seems to be one of them) will 
never fail `findfirst' if you include FA_LABEL attribute, but will 
instead return garbage in the ff_blk structure.  Therefore, `stat' now 
looks for volume labels only if the call without FA_LABEL failed, and 
always compares the name returned with the pathname you passed as the 
argument to `stat' to be sure that `findfirst' indeed have found a volume 
label and not returned garbled values due to poor implementation of a 
network redirector.

*** src/libc/posix/sys/stat/stat.c~0	Thu Oct 31 12:36:20 1996
--- src/libc/posix/sys/stat/stat.c	Thu Oct 31 13:29:48 1996
*************** stat_assist(const char *path, struct sta
*** 620,625 ****
--- 620,628 ----
      }
    else
      {
+       int i = 0;
+       int j = strlen (path) - 1;
+ 
        /* Check for volume labels.  We did not mix FA_LABEL with
  	 other attributes in the call to `__findfirst' above,
  	 because some environments will return bogus info in
*************** stat_assist(const char *path, struct sta
*** 630,637 ****
  	 label.  Hence we test the returned name to be PATH.  */
        if (!__findfirst(path, &ff_blk, FA_LABEL))
  	{
! 	  int i = strlen (ff_blk.ff_name) - 1;
! 	  int j = strlen (path) - 1;
  
  	  if (j >= i)
  	    {
--- 633,639 ----
  	 label.  Hence we test the returned name to be PATH.  */
        if (!__findfirst(path, &ff_blk, FA_LABEL))
  	{
! 	  i = strlen (ff_blk.ff_name) - 1;
  
  	  if (j >= i)
  	    {
*************** stat_assist(const char *path, struct sta
*** 639,657 ****
  		if (toupper (ff_blk.ff_name[i]) != toupper (path[j]))
  		  break;
  	    }
  
! 	  if (i < 0 && path[j] == '/')
! 	    {
! 	      /* Indeed a label.  */
! 	      statbuf->st_mode = READ_ACCESS;
  #ifdef  S_IFLABEL
! 	      statbuf->st_mode |= S_IFLABEL;
  #endif
! 	      statbuf->st_ino = 1;
! 	      statbuf->st_size = 0;
! 	      dos_ftime =
! 		( (unsigned)ff_blk.ff_fdate << 16 ) + ff_blk.ff_ftime;
! 	    }
  	}
        else
  	{
--- 641,658 ----
  		if (toupper (ff_blk.ff_name[i]) != toupper (path[j]))
  		  break;
  	    }
+ 	}
  
!       if (i < 0 && path[j] == '/')
! 	{
! 	  /* Indeed a label.  */
! 	  statbuf->st_mode = READ_ACCESS;
  #ifdef  S_IFLABEL
! 	  statbuf->st_mode |= S_IFLABEL;
  #endif
! 	  statbuf->st_ino = 1;
! 	  statbuf->st_size = 0;
! 	  dos_ftime = ( (unsigned)ff_blk.ff_fdate << 16 ) + ff_blk.ff_ftime;
  	}
        else
  	{