Description
Describe the bug
exists() returns false when given a path to an NTFS reparse point that points to a volume.
Additionally, status() returns not_found for such path.
To Reproduce
In Disk Manager, format a new volume. Instead of assigning a drive-letter, assign a mount-point at an empty directory on an NTFS volume.
Call exists() and pass in the path to the mount point.
Observe it returning false, even though the volume exists and is mounted.
Expected behavior
exists() is expected to return true.
Additional context
The problem arises from resolving a "symlink", in status_ex. The symlink being an IO_REPARSE_TAG_MOUNT_POINT is handled here.
The symlink resolves to something of this form: "\??\Volume{<GUID>}". This path is correct. However, it's assigned into a path object (result = ). The path assign() member function will strip the \??\ prefix, which makes the path incorrect.
Recursing down into another call to status_ex() (here) will then fail saying the path doesn't exist (because it doesn't).
Removing the code that's stripping the prefix fixes the problem:
--- a/filesystem.hpp
+++ b/filesystem.hpp
@@ -1663,9 +1663,9 @@ GHC_INLINE void path::postprocess_path_with_format(path::impl_string_type& p, pa
p[0] = '\\';
}
}
- else if (detail::startsWith(p, std::string("\\??\\"))) {
- p.erase(0, 4);
- }
+// else if (detail::startsWith(p, std::string("\\??\\"))) {
+// p.erase(0, 4);
+// }
}
for (auto& c : p) {
if (c == '\\') {
However, that is likely introducing other issues. Perhaps the best solution would be to have a resolveLink return a plain native sting (instead of path) and also make status_ex() accept a plain string, to avoid round-tripping via path in this case.