The file system rework introduced incompatibility between dircache
and the tagcache ramcache and playlist dircache path caching. This
update makes changes to filesystem code to reintegrate all that.
It also fixes a couple bugs that were found when vetting all the
code. The filestream cache was being reset without regard to
the stream even if it was shared in write mode (made work of
.playlist_control). Better handling of unmounting gives files a
better go at force-closing them without risk to disk integrity.
Did some miscellaneous pedantic changes. Improved efficiency of
testing a file's existence (a little) since the path parser will
be shared between file code and parsing for the sake of finding
dircache references, not duplicated as before.
This commit doesn't reenable said items just for the sake of
keeping changes separate and related.
Plan for the next is to enable dircache again for the playlists
(easy peasy) and reenable tagcache ramcache but *without* the
dircache path caching because it's rather substantial to change
in itself. The ramcache will still function without dircache.
Change-Id: I7e2a9910b866251fa8333e1275f72fcfc8425d2d
a931c76b3a