Remove trailing space from FAT label

Remove trailing space from FAT label

[phcoder]

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Hello. Here is the patch to remove trailing spaces from FAT label. These 
spaces generally aren't considiered to be part of label
Thanks
Vladimir 'phcoder' Serbinenko

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Index: fs/fat.c
===================================================================
--- fs/fat.c	(revision 1973)
+++ fs/fat.c	(working copy)
@@ -809,7 +809,13 @@
 
       if (dir.attr == GRUB_FAT_ATTR_VOLUME_ID)
 	{
-	  *label = grub_strndup ((char *) dir.name, 11);
+	  int labellen = 0, i;
+	  for (i = 0; i < 11; i++)
+	    if (dir.name[i] != ' ')
+	      labellen = i + 1;
+
+	  *label = grub_strndup ((char *) dir.name, labellen);
+	  
 	  return GRUB_ERR_NONE;
 	}
     }
Index: ChangeLog
===================================================================
--- ChangeLog	(revision 1973)
+++ ChangeLog	(working copy)
@@ -1,3 +1,9 @@
+2009-02-04  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	Remove trailing spaces from FAT label
+
+	* fs/fat.c (grub_fat_label): Remove trailing spaces
+
 2009-02-04  Felix Zielcke  <fzielcke@z-51.de>
 
 	util/getroot.c (grub_util_get_grub_dev): Add support for /dev/mdNpN and

Re: Remove trailing space from FAT label

[Pavel Roskin]

On Wed, 2009-02-04 at 13:01 +0100, phcoder wrote:
> Hello. Here is the patch to remove trailing spaces from FAT label. These 
> spaces generally aren't considiered to be part of label

Suppose the label is "DOS \0DDDDDDDD", then your algorithm will fail to
strip the final space, as it would iterate past the binary null.  I
don't know if it can happen, but I guess it's better to be prepared.

Also, please see how ordinary 8.3 filenames are handled.  Look for "8.3"
in fs/fat.c.  grub_isspace() is used to check for spaces.  Binary nulls
and spaces terminate the name.  There may be no spaces anywhere in the
name.

Perhaps we could use the same mechanism for the label except that no "."
is added.

-- 
Regards,
Pavel Roskin

Re: Remove trailing space from FAT label

[phcoder]

Hello
> Suppose the label is "DOS \0DDDDDDDD", 
Such a label is incorrect. But I agree with you that we should reuse the 
  code and be fault-tolerant (I regularly see FAT volumes breaking the 
specifications). Additionally there is a mechanism of nice fat label 
which works the same way as long names (supported only by some OS). 
Unifying the code would make these labels accessible. So I'll write a 
new proposition soon.
Thanks
Vladimir 'phcoder' Serbinenko

Re: Remove trailing space from FAT label

[Robert Millan]

On Wed, Feb 04, 2009 at 01:01:55PM +0100, phcoder wrote:
> Hello. Here is the patch to remove trailing spaces from FAT label. These 
> spaces generally aren't considiered to be part of label
> Thanks
> Vladimir 'phcoder' Serbinenko

> Index: fs/fat.c
> ===================================================================
> --- fs/fat.c	(revision 1973)
> +++ fs/fat.c	(working copy)
> @@ -809,7 +809,13 @@
>  
>        if (dir.attr == GRUB_FAT_ATTR_VOLUME_ID)
>  	{
> -	  *label = grub_strndup ((char *) dir.name, 11);
> +	  int labellen = 0, i;
> +	  for (i = 0; i < 11; i++)

Please use a descriptive macro instead of hardcoding 11.

-- 
Robert Millan

  The DRM opt-in fallacy: "Your data belongs to us. We will decide when (and
  how) you may access your data; but nobody's threatening your freedom: we
  still allow you to remove your data and not access it at all."