- FspFileSystemAcquireDirectoryBufferEx takes hint for initial capacity.
- Buffer allocation strategy has been improved to minimize reallocation.
- Quick sort of directory entries now implements median of three partitioning. This improves performance of sorting already sorted data.
- Symlinks: Now supports conventing a directory into a symlink reparse
point.
- Symlinks: The determination of whether a symlink is a file or
directory is now possible for file systems that do not support slashdot
(/.) queries.
- EA: Now allows the removal of non-existant EA without error (this is
allowed on Windows).
The original WinFsp protocol for shutting down a file system was to issue
an FSP_FSCTL_STOP control code to the fsctl device. This would set the IOQ
to the "stopped" state and would also cancel all active IRP's. Cancelation
of IRP's would sometimes free buffers that may have still been in use by
the user mode file system threads; hence access violation.
To fix this problem a new control code FSP_FSCTL_STOP0 is introduced. The
new file system shutdown protocol is backwards compatible with the original
one and works as follows:
- First the file system process issues an FSP_FSCTL_STOP0 control code which
sets the IOQ to the "stopped" state but does NOT cancel IRP's.
- Then the file system process waits for its dispatcher threads to complete
(see FspFileSystemStopDispatcher).
- Finally the file system process issues an FSP_FSCTL_STOP control code
which stops the (already stopped) IOQ and cancels all IRP's.
mingw-w64 declares _FILE_FULL_EA_INFORMATION since Jan 18, 2010 [1].
The change allows the winfsp client library to be consumed by projects built with mingw.
[1]: afd1465722
The FSP_FSCTL_QUERY_WINFSP code provides a simple method to determine if
the file system backing a file is a WinFsp file system. To use issue a
DeviceIoControl(Handle, FSP_FSCTL_QUERY_WINFSP, 0, 0, 0, 0, &Bytes, 0)
If the return value is TRUE this is a WinFsp file system.
