* dirmngr/http.c (HTTP_SESSION_MAGIC): New.
(http_session_s): New field 'magic'.
(HTTP_CONTEXT_MAGIC): New.
(http_context_s): New field 'magic'.
(my_ntbtls_verify_cb): Assert MAGIC.
(fp_onclose_notification): Ditto.
(session_unref): Ditto. Reset MAGIC.
(http_session_new): Set MAGIC.
(http_open): Ditto.
(http_raw_connect): Ditto.
(http_close): Assert MAGIC. Reset MAGIC.
* dirmngr/t-http.c (my_http_tls_verify_cb): MArk HTTP_FLAGS unused.
--
We pass those handles through opaque pointers. The magic numbers will
help to detect wrong use.
Signed-off-by: Werner Koch <wk@gnupg.org>