IsMemberOf is called for every file (in the ownCloud directory or not) and
with every instance of OCOverlay (we have 5) when displaying a list of
files in Explorer.
Refactor the code to avoid copying the list of watched directories, as
well as creating a wstring from a PWWSTR for files outside watched
directories.
Also change some calls of begin_with to use isDescendantOf since it
properly handles parent paths not ending with a backslash, which could
lead to SocketAPI queries for sibling folders with a name that starts with
a watched folder name.
There is a race condition that can initialize the RemotePathChecker
instance concurrently on the same address and cause a crash when locking
the mutex. The reason is that local static initialization is not
thread-safe with MSVC2013.
Fix the issue by using call_once to initialize a static unique_ptr
instead.
This could be related to some reports of issue #2836.
It seems like verclsid.exe hangs on our class IDs when invoked
through explorer.exe for 5-10 seconds. It doesn't hang if I
invoke the same command line from cmd.exe, so there could be some
process parameters that don't play well with our extra thread
or to the pipe connection that we do in it.
Delay creating the RemotePathChecker thread until the first
IsMemberOf call. verclsid.exe only seems to instantiate a object
of each registered class, without actually using them, so we
can use this as a workaround.
This should be fixing issue #2680.
