[shellpath.c]: minor fix to Rolf's patch

[Fabrice Ménard]

> <menard.fabrice at wanadoo.fr> wrote:
> 
> >The latest patch from Rolf Kalbermatter on shellpath.c was breaking the installation of wine.inf.
> >
> > wine rundll32 setupapi.dll,InstallHinfSection DefaultInstall 128 d:\\wine.inf
> >
> >was returning errors about being unable to create some dirs.  In facts these errors was concerning 
> >already existing directories in SHGetFolderPathW.
> 
> I believe this patch is not fully correct. I noticed these errors too after the patch was applied,
> but did a little more investigation. SHCreateDirectoryEx should never be called if the directory
> already exists since this is explicitedly tested before the call to the function with PathFileExistsW().

I came to the same conclusion as you.  In fact, the SHCreateDirectoryEx function is never called if the "entire" 
path already exists (due to the first PathFileExistsW).  The problem comes, as you saw it, with the intermediate 
components of the path.
 
> Also inside the SHCreateDirectoryEx function I saw that the first call to CreateDirectory fails since
> intermediate directories are missing and then in the recursive call to CreateDirectory every single
> call returns ERROR_ALREAY_EXISTS on my system in spite of that it actually creates the last two or
> three directories in there.

> My investigations showed that in spite of that some of the the top level directories do not exist, the
> function NtCreateFile() which is ultimately called does seem to return an according NT status when
> called from SHGetFolderPath() but does create the directory nevertheless.
> 
> Strange thing is that I can't reproduce this behaviour when calling SHCreateDirectoryEx() with many
> different parameters from an extended test in tests/shfileop.c
> 
> So I believe the root cause really seems somewhere else, namely NTCreateFile or maybe wineserver itself,
> but I hadn't time to further go into details.
> 
> >I think it is not necessary to care about that in this function so I added a check on the
> >type of error returned by SHCreateDirectoryExW. 
> 
> ShCreateDirectory should fail with that error if the directory really already existed.
> 
> Rolf Kalbermatter
>  
I agree that SHCreateDirectory should fail, but I'm not convinced it is crucial int the specific
SHGetFolderPathW function. But I may be wrong.

Anyway, I'll try to see if I can find a better solution.

Regards,
-- 
Fabrice Ménard
menard.fabrice at wanadoo.fr