tun: remove tun_finalize()

tun: remove tun_finalize()

tun_finalize() is essentially subset of socket_finalize() apart from:

 - using WSAFoo() functions instead of Foo()

 - "from" address is not returned

There is no clear official statement that one can use non-WSA
API on handles, so let's be on a safe side and use both.

Introduce sockethandle_t abstraction, which represents
socket and handle. Add SocketHandle* routines which call
proper API depends on underlying type in abstraction.

Rename socket_finalize() to sockethandle_finalize(), take
sockethandle_t and new routines into use and kick tun_finalize().

Signed-off-by: Lev Stipakov <lev@openvpn.net>
Acked-by: Selva Nair <selva.nair@gmail.com>
Message-Id: <20220117094917.178-1-lstipakov@gmail.com>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg23555.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>