Pass through message to relevant processes with separate threads in passthrough mode

src/connector.c

@@ -176,6 +176,8 @@ static void invalidate_client(ckpool_t *ckp, conn_instance_t *ci, client_instanc
 	fd = drop_client(ci, client);
 	if (fd == -1)
 		return;
+	if (ckp->passthrough)
+		return;
 	sprintf(buf, "dropclient=%d", client->id);
 	send_proc(ckp->stratifier, buf);
 }
@@ -236,8 +238,7 @@ reparse:
 	msg[buflen] = 0;
 	client->bufofs -= buflen;
 	memmove(client->buf, client->buf + buflen, client->bufofs);
-	val = json_loads(msg, 0, NULL);
-	if (!val) {
+	if (!(val = json_loads(msg, 0, NULL))) {
 		char *buf = strdup("Invalid JSON, disconnecting\n");
 
 		LOGINFO("Client id %d sent invalid json message %s", client->id, msg);
@@ -250,7 +251,10 @@ reparse:
 		json_object_set_new_nocheck(val, "client_id", json_integer(client->id));
 		json_object_set_new_nocheck(val, "address", json_string(client->address_name));
 		s = json_dumps(val, 0);
-		send_proc(ckp->stratifier, s);
+		if (ckp->passthrough)
+			send_proc(ckp->generator, s);
+		else
+			send_proc(ckp->stratifier, s);
 		free(s);
 		json_decref(val);
 	}

src/generator.c

@@ -63,6 +63,13 @@ struct stratum_msg {
 
 typedef struct stratum_msg stratum_msg_t;
 
+struct pass_msg {
+	connsock_t *cs;
+	char *msg;
+};
+
+typedef struct pass_msg pass_msg_t;
+
 /* Per proxied pool instance data */
 struct proxy_instance {
 	ckpool_t *ckp;
@@ -109,6 +116,8 @@ struct proxy_instance {
 	pthread_mutex_t share_lock;
 	share_msg_t *shares;
 	int share_id;
+
+	ckmsgq_t *passsends;	// passthrough sends
 };
 
 typedef struct proxy_instance proxy_instance_t;
@@ -1169,6 +1178,59 @@ static void *proxy_send(void *arg)
 	return NULL;
 }
 
+/* For receiving messages from an upstream pool to pass downstream */
+static void *passthrough_recv(void *arg)
+{
+	proxy_instance_t *proxi = (proxy_instance_t *)arg;
+	connsock_t *cs = proxi->cs;
+	ckpool_t *ckp = proxi->ckp;
+
+	rename_proc("passrecv");
+
+	while (42) {
+		int ret;
+
+		do {
+			ret = read_socket_line(cs, 60);
+		} while (ret == 0);
+
+		if (ret < 1) {
+			/* Send ourselves a reconnect message */
+			LOGWARNING("Failed to read_socket_line in proxy_recv, attempting reconnect");
+			send_proc(ckp->generator, "reconnect");
+			break;
+		}
+		/* Simply forward the message on, as is, to the connector to
+		 * process. Possibly parse parameters sent by upstream pool
+		 * here */
+		send_proc(ckp->connector, cs->buf);
+	}
+	return NULL;
+}
+
+static void passthrough_send(ckpool_t __maybe_unused *ckp, pass_msg_t *pm)
+{
+	int len, sent;
+
+	LOGDEBUG("Sending upstream json msg: %s", pm->msg);
+	len = strlen(pm->msg);
+	sent = write_socket(pm->cs->fd, pm->msg, len);
+	if (sent != len) {
+		LOGWARNING("Failed to passthrough %d bytes of message %s", len, pm->msg);
+	}
+	free(pm->msg);
+	free(pm);
+}
+
+static void passthrough_add_send(proxy_instance_t *proxi, const char *msg)
+{
+	pass_msg_t *pm = ckzalloc(sizeof(pass_msg_t));
+
+	pm->cs = proxi->cs;
+	pm->msg = strdup(msg);
+	ckmsgq_add(proxi->passsends, pm);
+}
+
 /* Cycle through the available proxies and find the first alive one */
 static proxy_instance_t *live_proxy(ckpool_t *ckp)
 {
@@ -1232,10 +1294,15 @@ retry:
 	LOGNOTICE("Connected to upstream server %s:%s as proxy%s", cs->url, cs->port,
 		  ckp->passthrough ? " in passthrough mode" : "");
 	mutex_init(&alive->notify_lock);
-	create_pthread(&alive->pth_precv, proxy_recv, alive);
-	mutex_init(&alive->psend_lock);
-	cond_init(&alive->psend_cond);
-	create_pthread(&alive->pth_psend, proxy_send, alive);
+	if (ckp->passthrough) {
+		create_pthread(&alive->pth_precv, passthrough_recv, alive);
+		alive->passsends = create_ckmsgq(ckp, "passsend", &passthrough_send);
+	} else {
+		create_pthread(&alive->pth_precv, proxy_recv, alive);
+		mutex_init(&alive->psend_lock);
+		cond_init(&alive->psend_cond);
+		create_pthread(&alive->pth_psend, proxy_send, alive);
+	}
 out:
 	send_proc(ckp->connector, alive ? "accept" : "reject");
 	return alive;
@@ -1326,6 +1393,9 @@ retry:
 	} else if (cmdmatch(buf, "ping")) {
 		LOGDEBUG("Proxy received ping request");
 		send_unix_msg(sockd, "pong");
+	} else if (ckp->passthrough) {
+		/* Anything remaining should be stratum messages */
+		passthrough_add_send(proxi, buf);
 	} else {
 		/* Anything remaining should be share submissions */
 		json_t *val = json_loads(buf, 0, NULL);