struct method: introduce con-/destructors

These can be used before setting up or after closing down a socket
for protocol-specific initialisiation or cleanup, and are required
to cleanly fix up the IMAP-loses-protocol-version regression without
too many temporary hacks in the code.

2 files changed, 13 insertions, 0 deletions

diff --git a/driver.c b/driver.c
index 5421c766..78e72df6 100644
--- a/driver.c
+++ b/driver.c
@@ -965,6 +965,12 @@ static int do_session(
 	    goto closeUp;
 	}
 
+	/* initialize protocol */
+	if (ctl->server.base_protocol->construct) {
+	    err = (ctl->server.base_protocol->construct)(ctl);
+	    if (err) goto cleanUp;
+	}
+
 	/* open a socket to the mail server */
 	oldphase = phase;
 	phase = OPEN_WAIT;
@@ -1547,6 +1553,11 @@ is restored."));
 	    cleanupSockClose(mailserver_socket_temp);
 	    mailserver_socket_temp = -1;
 	}
+
+	/* clean up protocol */
+	if (ctl->server.base_protocol->destruct) {
+	    ctl->server.base_protocol->destruct(ctl);
+	}
     }
 
     /* no report on PS_AUTHFAIL */
diff --git a/fetchmail.h b/fetchmail.h
index d976f481..a1b77468 100644
--- a/fetchmail.h
+++ b/fetchmail.h
@@ -249,6 +249,8 @@ struct method		/* describe methods for protocol state machine */
     int (*logout_cmd)(int, struct query *);
 				/* logout command */
     flag retry;			/* can getrange poll for new messages? */
+    int (*construct)(struct query *); /* session setup before first command */
+    int (*destruct)(struct query *); /* cleanup after session */
 };
 
 enum badheader { BHREJECT = 0, BHACCEPT };