background is always rendered on region depending on renderer

This avoids leaking disk space if VLC does not terminate cleanly.

The vlc_stat() call did not really ensure that the directory was usable
(space and permission), nor that it would still exist when needed.

Now instead, try to create the temporary file and fall back to the
default path if that fails.

Avoid leaking subpicture if vout is never opened.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

There are no needs to keep a copy of this on the stack. Besides, the
value could change if we supported threaded audio decoding.

tp is another extension for ts.

This occurs in case of large buffer underflow, such as if stopping the
VLC process.

Cork state could change asynchronously without the PA lock.