Add persistency for events

Persist event D-bus objects using cereal

Resolves openbmc/openbmc#2319

Change-Id: Ifa15d944fe1d1026761f65eeb647dcbdf6afdba0
Signed-off-by: Dhruvaraj Subhashchandran <dhruvaraj@in.ibm.com>
diff --git a/src/event_serialize.hpp b/src/event_serialize.hpp
new file mode 100644
index 0000000..f052845
--- /dev/null
+++ b/src/event_serialize.hpp
@@ -0,0 +1,30 @@
+#pragma once
+
+#include <experimental/filesystem>
+#include "event_entry.hpp"
+#include "config.h"
+
+namespace phosphor
+{
+namespace events
+{
+
+namespace fs = std::experimental::filesystem;
+
+/** @brief Serialize and persist event d-bus object
+ *  @param[in] event - const reference to event entry.
+ *  @param[in] eventName - Name of the event.
+ *  @return fs::path - pathname of persisted events file
+ */
+fs::path serialize(const Entry& event, const std::string& eventName);
+
+/** @brief Deserialze a persisted event into a d-bus object
+ *  @param[in] path - pathname of persisted event file
+ *  @param[in] event - reference to event object which is the target of
+ *             deserialization.
+ *  @return bool - true if the deserialization was successful, false otherwise.
+ */
+bool deserialize(const fs::path& path, Entry& event);
+
+} // namespace events
+} // namespace phosphor