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diff --git a/src/connhelpers.h b/src/connhelpers.h
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+
+/*
+ * Copyright (c) 2019, Redis Labs
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __REDIS_CONNHELPERS_H
+#define __REDIS_CONNHELPERS_H
+
+#include "connection.h"
+
+/* These are helper functions that are common to different connection
+ * implementations (currently sockets in connection.c and TLS in tls.c).
+ *
+ * Currently helpers implement the mechanisms for invoking connection
+ * handlers, tracking in-handler states and dealing with deferred
+ * destruction (if invoked by a handler).
+ */
+
+/* Called whenever a handler is invoked on a connection and sets the
+ * CONN_FLAG_IN_HANDLER flag to indicate we're in a handler context.
+ *
+ * An attempt to close a connection while CONN_FLAG_IN_HANDLER is
+ * set will result with deferred close, i.e. setting the CONN_FLAG_CLOSE_SCHEDULED
+ * instead of destructing it.
+ */
+static inline void enterHandler(connection *conn) {
+    conn->flags |= CONN_FLAG_IN_HANDLER;
+}
+
+/* Called whenever a handler returns. This unsets the CONN_FLAG_IN_HANDLER
+ * flag and performs actual close/destruction if a deferred close was
+ * scheduled by the handler.
+ */
+static inline int exitHandler(connection *conn) {
+    conn->flags &= ~CONN_FLAG_IN_HANDLER;
+    if (conn->flags & CONN_FLAG_CLOSE_SCHEDULED) {
+        connClose(conn);
+        return 0;
+    }
+    return 1;
+}
+
+/* Helper for connection implementations to call handlers:
+ * 1. Mark the handler in use.
+ * 2. Execute the handler (if set).
+ * 3. Mark the handler as NOT in use and perform deferred close if was
+ * requested by the handler at any time.
+ */
+static inline int callHandler(connection *conn, ConnectionCallbackFunc handler) {
+    conn->flags |= CONN_FLAG_IN_HANDLER;
+    if (handler) handler(conn);
+    conn->flags &= ~CONN_FLAG_IN_HANDLER;
+    if (conn->flags & CONN_FLAG_CLOSE_SCHEDULED) {
+        connClose(conn);
+        return 0;
+    }
+    return 1;
+}
+
+#endif  /* __REDIS_CONNHELPERS_H */