Abstract out the testing of whether a server is alive to be used for future fallback code

src/generator.c

@@ -122,27 +122,17 @@ struct proxy_instance {
 
 typedef struct proxy_instance proxy_instance_t;
 
-static server_instance_t *live_server(ckpool_t *ckp)
+static bool server_alive(ckpool_t *ckp, server_instance_t *si, bool pinging)
 {
-	server_instance_t *alive = NULL;
-	connsock_t *cs;
-	int i;
-
-	LOGDEBUG("Attempting to connect to bitcoind");
-retry:
-	if (!ping_main(ckp))
-		goto out;
-
-	for (i = 0; i < ckp->btcds; i++) {
-		server_instance_t *si;
 	char *userpass = NULL;
+	bool ret = false;
+	connsock_t *cs;
 	gbtbase_t *gbt;
 
-		si = ckp->servers[i];
 	cs = &si->cs;
 	if (!extract_sockaddr(si->url, &cs->url, &cs->port)) {
 		LOGWARNING("Failed to extract address from %s", si->url);
-			continue;
+		return ret;
 	}
 	userpass = strdup(si->auth);
 	realloc_strcat(&userpass, ":");
@@ -151,33 +141,60 @@ retry:
 	dealloc(userpass);
 	if (!cs->auth) {
 		LOGWARNING("Failed to create base64 auth from %s", userpass);
-			continue;
+		return ret;
 	}
 
 	cs->fd = connect_socket(cs->url, cs->port);
 	if (cs->fd < 0) {
+		if (!pinging)
 			LOGWARNING("Failed to connect socket to %s:%s !", cs->url, cs->port);
-			continue;
+		return ret;
 	}
 
-		keep_sockalive(cs->fd);
-
 	/* Test we can connect, authorise and get a block template */
 	gbt = ckzalloc(sizeof(gbtbase_t));
 	si->data = gbt;
 	if (!gen_gbtbase(cs, gbt)) {
+		if (!pinging) {
 			LOGINFO("Failed to get test block template from %s:%s!",
 				cs->url, cs->port);
-			continue;
+		}
+		goto out_close;
 	}
 	clear_gbtbase(gbt);
 	if (!validate_address(cs, ckp->btcaddress)) {
 		LOGWARNING("Invalid btcaddress: %s !", ckp->btcaddress);
-			continue;
+		goto out_close;
 	}
+	ret = true;
+out_close:
+	if (!ret)
+		close(cs->fd);
+	else
+		keep_sockalive(cs->fd);
+	return ret;
+}
+
+/* Find the highest priority server alive and return it */
+static server_instance_t *live_server(ckpool_t *ckp)
+{
+	server_instance_t *alive = NULL;
+	connsock_t *cs;
+	int i;
+
+	LOGDEBUG("Attempting to connect to bitcoind");
+retry:
+	if (!ping_main(ckp))
+		goto out;
+
+	for (i = 0; i < ckp->btcds; i++) {
+		server_instance_t *si = ckp->servers[i];
+
+		if (server_alive(ckp, si, false)) {
 			alive = si;
 			break;
 		}
+	}
 	if (!alive) {
 		LOGWARNING("CRITICAL: No bitcoinds active!");
 		sleep(5);