Look for other clients that should have been dropped in the stratifier and inform or query the connector about them

src/connector.c

@@ -239,7 +239,7 @@ static int drop_client(cdata_t *cdata, client_instance_t *client)
 	return fd;
 }
 
-static void stratifier_drop_client(ckpool_t *ckp, int64_t id)
+static void stratifier_drop_client(ckpool_t *ckp, const int64_t id)
 {
 	char buf[256];
 
@@ -601,6 +601,17 @@ static void send_client(cdata_t *cdata, int64_t id, char *buf)
 	mutex_unlock(&cdata->sender_lock);
 }
 
+static bool client_exists(cdata_t *cdata, const int64_t id)
+{
+	client_instance_t *client;
+
+	ck_rlock(&cdata->lock);
+	HASH_FIND_I64(cdata->clients, &id, client);
+	ck_runlock(&cdata->lock);
+
+	return !!client;
+}
+
 static client_instance_t *ref_client_by_id(cdata_t *cdata, int64_t id)
 {
 	client_instance_t *client;
@@ -774,7 +785,7 @@ retry:
 		client_instance_t *client;
 
 		ret = sscanf(buf, "dropclient=%"PRId64, &client_id64);
-		if (ret < 0) {
+		if (unlikely(ret < 0)) {
 			LOGDEBUG("Connector failed to parse dropclient command: %s", buf);
 			goto retry;
 		}
@@ -788,6 +799,17 @@ retry:
 		dec_instance_ref(cdata, client);
 		if (ret >= 0)
 			LOGINFO("Connector dropped client id: %"PRId64, client_id);
+	} else if (cmdmatch(buf, "testclient")) {
+		ret = sscanf(buf, "testclient=%"PRId64, &client_id64);
+		if (unlikely(ret < 0)) {
+			LOGDEBUG("Connector failed to parse testclient command: %s", buf);
+			goto retry;
+		}
+		client_id = client_id64 & 0xffffffffll;
+		if (client_exists(cdata, client_id))
+			goto retry;
+		LOGINFO("Connector detected non-existent client id: %"PRId64, client_id);
+		stratifier_drop_client(ckp, client_id);
 	} else if (cmdmatch(buf, "ping")) {
 		LOGDEBUG("Connector received ping request");
 		send_unix_msg(sockd, "pong");

src/stratifier.c

@@ -1805,6 +1805,17 @@ static void dec_worker(ckpool_t *ckp, user_instance_t *instance)
 	mutex_unlock(&sdata->stats_lock);
 }
 
+/* Ask the connector asynchronously to send us dropclient commands if this
+ * client no longer exists. */
+static void connector_test_client(ckpool_t *ckp, const int64_t id)
+{
+	char buf[256];
+
+	LOGDEBUG("Stratifier requesting connector test client %"PRId64, id);
+	snprintf(buf, 255, "testclient=%"PRId64, id);
+	async_send_proc(ckp, ckp->connector, buf);
+}
+
 static void drop_client(ckpool_t *ckp, sdata_t *sdata, const int64_t id)
 {
 	stratum_instance_t *client, *tmp;
@@ -1814,7 +1825,25 @@ static void drop_client(ckpool_t *ckp, sdata_t *sdata, const int64_t id)
 
 	LOGINFO("Stratifier asked to drop client %"PRId64, id);
 
+	/* Use this locking as an opportunity to test other clients. */
 	ck_ilock(&sdata->instance_lock);
+	/* Test for clients that haven't authed in over a minute and drop them */
+	HASH_ITER(hh, sdata->stratum_instances, client, tmp) {
+		if (client->authorised)
+			continue;
+		if (now_t > client->start_time + 60) {
+			client->dropped = true;
+			connector_drop_client(ckp, client->id);
+		}
+	}
+
+	/* Look for clients that may have been dropped which the stratifer has
+	 * not been informed about and ask the connector of they still exist */
+	HASH_ITER(hh, sdata->stratum_instances, client, tmp) {
+		if (client->dropped || client->reconnect)
+			connector_test_client(ckp, client->id);
+	}
+
 	client = __instance_by_id(sdata, id);
 	/* Upgrade to write lock */
 	ck_ulock(&sdata->instance_lock);