Function clusterAcceptHandler

app/redis-6.2.6/src/cluster.c:676–727

#define MAX_CLUSTER_ACCEPTS_PER_CALL 1000
void clusterAcceptHandler(aeEventLoop *el, int fd, void *privdata, int mask) {
    int cport, cfd;
    int max = MAX_CLUSTER_ACCEPTS_PER_CALL;
    char cip[NET_IP_STR_LEN];
    UNUSED(el);
    UNUSED(mask);
    UNUSED(privdata);

    /* If the server is starting up, don't accept cluster connections:
     * UPDATE messages may interact with the database content. */
    if (server.masterhost == NULL && server.loading) return;

    while(max--) {
        cfd = anetTcpAccept(server.neterr, fd, cip, sizeof(cip), &cport);
        if (cfd == ANET_ERR) {
            if (errno != EWOULDBLOCK)
                serverLog(LL_VERBOSE,
                    "Error accepting cluster node: %s", server.neterr);
            return;
        }

        connection *conn = server.tls_cluster ?
            connCreateAcceptedTLS(cfd, TLS_CLIENT_AUTH_YES) : connCreateAcceptedSocket(cfd);

        /* Make sure connection is not in an error state */
        if (connGetState(conn) != CONN_STATE_ACCEPTING) {
            serverLog(LL_VERBOSE,
                "Error creating an accepting connection for cluster node: %s",
                    connGetLastError(conn));
            connClose(conn);
            return;
        }
        connNonBlock(conn);
        connEnableTcpNoDelay(conn);
        connKeepAlive(conn,server.cluster_node_timeout * 2);

        /* Use non-blocking I/O for cluster messages. */
        serverLog(LL_VERBOSE,"Accepting cluster node connection from %s:%d", cip, cport);

        /* Accept the connection now.  connAccept() may call our handler directly
         * or schedule it for later depending on connection implementation.
         */
        if (connAccept(conn, clusterConnAcceptHandler) == C_ERR) {
            if (connGetState(conn) == CONN_STATE_ERROR)
                serverLog(LL_VERBOSE,
                        "Error accepting cluster node connection: %s",
                        connGetLastError(conn));
            connClose(conn);
            return;
        }
    }
}

/* Return the approximated number of sockets we are using in order to
 * take the cluster bus connections. */