Erik discovered this bug when testing bug 2440, I believe.
Currently, our unfsd.exe is unable to export a Samba share in Windows. This is due to some strange behaviour of "." and "..": On at least my H: on my laptop, _wreaddir() returns ".." on H: but not on C. This causes unfsd.exe to try backend_lstat() on /h/.., which in turn calls intpath2winpath. This function is clearly incorrect: It returns the empty string, in this case. For "/h/.", the result is "h", which is also incorrect.
Some unit tests for intpath2winpath might be good.
If "/h/.." should be translated to "h:\.." or some identifier for the virtual root is an open question. We should probably also take a look at the rest of unfsd, to make sure it handles "." and ".." properly.