[Libguestfs] [PATCH 1/3] New API: case-sensitive-path to return case sensitive path on NTFS 3g fs

[Richard W.M. Jones]

On Mon, Oct 26, 2009 at 01:16:15PM +0000, Matthew Booth wrote:
> .. or the guestfish user who types 'cat  
> win:c:\windows\system32\blah.txt' and doesn't get the result they  
> intended. Essentially you need to do this in 2 cases: you read a path  
> from a config file, or you're accessing a file whose location you  
> already know. In either case, the additional call is just untidiness.

I don't understand this point.

Who told them to look at "c:\windows\system32\blah.txt"?
It must have come from a Windows config file, a Windows document or a
book, and that path is not case-sensitive.

>> In any other case, using case_sensitive_path is almost certainly
>> wrong, in fact not just slow but quite likely to be insecure too.  You
>> don't want a Linux config file that specifies /etc/something to
>> randomly pick /etc/SOMETHING.
>
> It's a very good point. You can fix this, though. When iterating down  
> the directory structure, you'll open a file to check if it's a  
> directory. At the same time, to fstatfs() to check what filesystem it's  
> on. By doing this you can choose directory-by-directory whether or not  
> to be case-sensitive. This should always be safe.

fstatfs doesn't tell you if a filesystem is case sensitive, and in any
case that is irrelevant.  Think of the imaginary Windows-on-ext3 case
where you'd still have Windows containing case-insensitive
configuration paths, even if the filesystem is case-sensitive.

Rich.

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