[Bug 22286] New: GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

Summary: GetShortPathName -> GetLongPathName doesn't give back
                    same file
           Product: Wine
           Version: unspecified
          Platform: x86
               URL: http://cmake.org
        OS/Version: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: kernel32
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

Some people are using a cmake/mingw/msys/wine combination on Linux to
compile/test code targeting Windows, and its currently being discussed on the
cmake user's list.

CMake uses a GetShortPathName() / GetLongPathName() trick to get the actual
case for a filename.

If the a directory contains these two files (from a CMake installation, but can
be empty files),
CMakeFortranInformation.cmake
CMakeTestCXXCompiler.cmake
and GetShortPathName()/GetLongPathName() is called for
CMakeTestCXXCompiler.cmake, it returns the other file instead.

======

#include <windows.h>
#include <stdio.h>

int main(int argc, char** argv)
{
  if(argc < 2)
  {
    printf("Usage: %s filename\n", argv[0]);
    return 1;
  }

char buffer[MAX_PATH+1];
  char buffer2[MAX_PATH+1];

GetShortPathName(argv[1], buffer, MAX_PATH+1);
  GetLongPathNameA(buffer, buffer2, MAX_PATH+1);
  printf("%s\n", buffer2);

return 0;
}

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #1 from Clinton Stimpson   2010-04-05 18:42:35 ---

And the output I get when calling the program is this:

$ ./a.out CMakeTestCXXCompiler.cmake 
CMakeFortranInformation.cmake

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #2 from Dmitry Timoshkov   2010-04-05 22:35:50 ---
Wine version?

Please add a test case to the Wine test suite and send it to wine-patches.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #3 from Jeff Zaroyko   2010-04-05 23:01:36 ---
I can't reproduce this with your testcase under wine 1.1.42.

jeffz@genera:/tmp/foo$ touch CMakeFortranInformation.cmake
jeffz@genera:/tmp/foo$ touch CMakeTestCXXCompiler.cmake
jeffz@genera:/tmp/foo$ ~/git/wine/wine ../name.exe CMakeTestCXXCompiler.cmake
CMakeTestCXXCompiler.cmake

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

Austin English  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |download, source, testcase

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #4 from Alexandre Julliard   2010-04-06 03:19:23 ---
That's a hash collision, the two names will hash to the same short name. I
guess you are just unlucky... If you need reliable short names you have to use
a vfat filesystem.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #5 from Dmitry Timoshkov   2010-04-06 08:59:16 ---
(In reply to comment #4)
> That's a hash collision, the two names will hash to the same short name. I
> guess you are just unlucky... If you need reliable short names you have to use
> a vfat filesystem.

Is this basically a wontfix?

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #6 from Clinton Stimpson   2010-04-06 09:01:20 ---
I'm using git from a few days ago.  Is there another possible fix besides
telling people to use vfat instead of ext3?  Did you test on vfat?

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

John M. Drescher  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #7 from John M. Drescher   2010-04-06 09:08:57 ---
> > That's a hash collision, the two names will hash to the same short name. I
> > guess you are just unlucky... If you need reliable short names you have to use
> > a vfat filesystem.
>
> Is this basically a wontfix?

I think it will not be easy to fix. A hash algorithm will have collisions. The
native windows system gets around this problem by retaining the short file name
in the filesystem.

I wonder how samba solves this?

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

Alexandre Julliard  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |WONTFIX

--- Comment #8 from Alexandre Julliard   2010-04-06 09:33:17 ---
Yeah it's basically a wontfix. A correct solution would require storing short
names on disk, that would be very complex and not worth the trouble. Short
names need to die.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

Dmitry Timoshkov  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |CLOSED

--- Comment #9 from Dmitry Timoshkov   2010-04-06 09:58:40 ---
Closing wontfix.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #10 from Juan Lang   2010-04-06 11:22:24 ---
(In reply to comment #7)
> I wonder how samba solves this?

They don't, AFAIK.  There isn't an API to convert one style of name to another.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #11 from Juan Lang   2010-04-06 11:23:22 ---
(In reply to comment #10)
> They don't, AFAIK.  There isn't an API to convert one style of name to another.

Er, obviously there's a Win32 API to do so.  I mean, there isn't an SMB API to
do so.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #12 from John M. Drescher   2010-04-06 11:38:19 ---
I just tried the example from the first post from a samba share under windows
using the same cmake files and it worked as expected for the samba share.

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMakeTestFortranCompiler.cmake
U:\jdrescher\TestSambaShort\CMakeTestFortranCompiler.cmake

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMakeTestCXXCompiler.cmake
U:\jdrescher\TestSambaShort\CMakeTestCXXCompiler.cmake

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMakeTestForFreeVC.cxx
U:\jdrescher\TestSambaShort\CMakeTestForFreeVC.cxx

It looks like samba is doing the correct thing. However they may be storing the
short filenames somewhere or I may just be lucky not to hit the hash collision.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #13 from John M. Drescher   2010-04-06 11:39:59 ---
Here is a better example. Showing the case change.

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMaketestForFreeVC.cxx
U:\jdrescher\TestSambaShort\CMakeTestForFreeVC.cxx

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMaketestCXXCompiler.cmake
U:\jdrescher\TestSambaShort\CMakeTestCXXCompiler.cmake

[u:]c:TestSambaShortFileNames.exe
U:\jdrescher\TestSambaShort\CMaketestFortranCompiler.cmake
U:\jdrescher\TestSambaShort\CMakeTestFortranCompiler.cmake

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #14 from Juan Lang   2010-04-06 12:34:54 ---
(In reply to comment #12)
> It looks like samba is doing the correct thing. However they may be storing the
> short filenames somewhere or I may just be lucky not to hit the hash collision.

They are not storing the short filenames anywhere permanent.  Samba does keep a
cache of the last 50 (by default) name manglings on a share.  You also may be
getting lucky.  Like Jeff, the app doesn't produce a failure under Wine for me,
either.

[Bug 22286] GetShortPathName -> GetLongPathName doesn't give back same file

http://bugs.winehq.org/show_bug.cgi?id=22286

--- Comment #15 from John M. Drescher   2010-04-06 12:44:11 ---
We should probably take any further discussion to mailing list(s) since it's
closed/wontfix.