director: Improve debug logging output.

src/director/director-connection.c

@@ -776,23 +776,29 @@ director_cmd_host_hand_start(struct director_connection *conn,
 
 	if (remote_ring_completed && !conn->dir->ring_handshaked) {
 		/* clear everything we have and use only what remote sends us */
+		dir_debug("%s: We're joining a ring - replace all hosts",
+			  conn->name);
 		hosts = mail_hosts_get(conn->dir->mail_hosts);
 		while (array_count(hosts) > 0) {
 			hostp = array_idx(hosts, 0);
 			director_remove_host(conn->dir, NULL, NULL, *hostp);
 		}
 	} else if (!remote_ring_completed && conn->dir->ring_handshaked) {
 		/* ignore whatever remote sends */
+		dir_debug("%s: Remote is joining our ring - "
+			  "ignore all remote HOSTs", conn->name);
 		conn->ignore_host_events = TRUE;
+	} else {
+		dir_debug("%s: Merge rings' hosts", conn->name);
 	}
 	conn->handshake_sending_hosts = TRUE;
 	return TRUE;
 }
 
 static int
-director_cmd_is_seen(struct director_connection *conn,
-		     const char *const **_args,
-		     struct director_host **host_r)
+director_cmd_is_seen_full(struct director_connection *conn,
+			  const char *const **_args, unsigned int *seq_r,
+			  struct director_host **host_r)
 {
 	const char *const *args = *_args;
 	struct ip_addr ip;
@@ -808,6 +814,7 @@ director_cmd_is_seen(struct director_connection *conn,
 		return -1;
 	}
 	*_args = args + 3;
+	*seq_r = seq;
 
 	host = director_host_lookup(conn->dir, &ip, port);
 	if (host == NULL || host->removed) {
@@ -826,6 +833,16 @@ director_cmd_is_seen(struct director_connection *conn,
 	return 0;
 }
 
+static int
+director_cmd_is_seen(struct director_connection *conn,
+		     const char *const **_args,
+		     struct director_host **host_r)
+{
+	unsigned int seq;
+
+	return director_cmd_is_seen_full(conn, _args, &seq, host_r);
+}
+
 static bool
 director_cmd_user_weak(struct director_connection *conn,
 		       const char *const *args)
@@ -1185,18 +1202,26 @@ director_cmd_user_killed_everywhere(struct director_connection *conn,
 				    const char *const *args)
 {
 	struct director_host *dir_host;
-	unsigned int username_hash;
+	unsigned int seq, username_hash;
 	int ret;
 
-	if ((ret = director_cmd_is_seen(conn, &args, &dir_host)) != 0)
-		return ret > 0;
+	if ((ret = director_cmd_is_seen_full(conn, &args, &seq, &dir_host)) < 0)
+		return FALSE;
 
 	if (str_array_length(args) != 1 ||
 	    str_to_uint(args[0], &username_hash) < 0) {
 		director_cmd_error(conn, "Invalid parameters");
 		return FALSE;
 	}
 
+	if (ret > 0) {
+		i_assert(dir_host != NULL);
+		dir_debug("User %u - ignoring already seen USER-KILLED-EVERYWHERE "
+			  "with seq=%u <= %s.last_seq=%u", username_hash,
+			  seq, dir_host->name, dir_host->last_seq);
+		return TRUE;
+	}
+
 	director_user_killed_everywhere(conn->dir, conn->host,
 					dir_host, username_hash);
 	return TRUE;

src/director/director.c

@@ -791,6 +791,8 @@ director_flush_user(struct director *dir, struct user *user)
 		t_strdup_printf("%u", user->username_hash), NULL};
 
 	user->kill_state = USER_KILL_STATE_FLUSHING;
+	dir_debug("Flushing user %u via %s", user->username_hash,
+		  ctx->socket_path);
 
 	if ((program_client_create(ctx->socket_path, args, &set, FALSE,
 				   &ctx->pclient, &error)) != 0) {
@@ -816,6 +818,9 @@ static void director_user_move_free(struct director *dir, struct user *user)
 {
 	i_assert(user->to_move != NULL);
 
+	dir_debug("User %u move finished at state=%s", user->username_hash,
+		  user_kill_state_names[user->kill_state]);
+
 	user->kill_state = USER_KILL_STATE_NONE;
 	timeout_remove(&user->to_move);
 
@@ -1004,6 +1009,12 @@ void director_move_user(struct director *dir, struct director_host *src,
 				      username_hash);
 		ipc_client_cmd(dir->ipc_proxy, cmd,
 			       director_kill_user_callback, ctx);
+	} else {
+		/* User is being moved again before the previous move
+		   finished. We'll just continue wherever we left off
+		   earlier. */
+		dir_debug("User %u move restarted - previous kill_state=%s",
+			  username_hash, user_kill_state_names[user->kill_state]);
 	}
 
 	if (orig_src == NULL) {
@@ -1151,9 +1162,16 @@ void director_user_killed_everywhere(struct director *dir,
 	struct user *user;
 
 	user = user_directory_lookup(dir->users, username_hash);
-	if (user == NULL ||
-	    user->kill_state != USER_KILL_STATE_KILLED_WAITING_FOR_EVERYONE)
+	if (user == NULL) {
+		dir_debug("User %u no longer exists - ignoring USER-KILLED-EVERYWHERE",
+			  username_hash);
 		return;
+	}
+	if (user->kill_state != USER_KILL_STATE_KILLED_WAITING_FOR_EVERYONE) {
+		dir_debug("User %u kill_state=%s - ignoring USER-KILLED-EVERYWHERE",
+			  username_hash, user_kill_state_names[user->kill_state]);
+		return;
+	}
 
 	director_flush_user(dir, user);
 	director_send_user_killed_everywhere(dir, src, orig_src, username_hash);