Persist error d-bus objects

Use Cereal to implement serialization and de-serialization of
properties of error d-bus objects.

Serialize and persist error d-bus objects as they are put on the bus.
De-serialize and restore them (if persistent ones exist) when
phosphor-log-manager starts up.

Change-Id: I1f5df1abbe74bfdb86e3e82a78ff7115e90e2112
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/elog_serialize.hpp b/elog_serialize.hpp
new file mode 100644
index 0000000..d1bcbfb
--- /dev/null
+++ b/elog_serialize.hpp
@@ -0,0 +1,78 @@
+#pragma once
+
+#include <string>
+#include <vector>
+#include <experimental/filesystem>
+#include "elog_entry.hpp"
+#include "config.h"
+
+namespace phosphor
+{
+namespace logging
+{
+
+namespace fs = std::experimental::filesystem;
+
+/** @brief Function required by Cereal to perform serialization.
+ *  @tparam Archive - Cereal archive type (binary in our case).
+ *  @param[in] a - reference to Cereal archive.
+ *  @param[in] e - const reference to error entry.
+ */
+template<class Archive>
+void save(Archive& a, const Entry& e)
+{
+    a(e.id(), e.severity(), e.timestamp(),
+      e.message(), e.additionalData(), e.associations(), e.resolved());
+}
+
+/** @brief Function required by Cereal to perform deserialization.
+ *  @tparam Archive - Cereal archive type (binary in our case).
+ *  @param[in] a - reference to Cereal archive.
+ *  @param[in] e - reference to error entry.
+ */
+template<class Archive>
+void load(Archive& a, Entry& e)
+{
+    using namespace
+        sdbusplus::xyz::openbmc_project::Logging::server;
+
+    uint32_t id{};
+    Entry::Level severity{};
+    uint64_t timestamp{};
+    std::string message{};
+    std::vector<std::string> additionalData{};
+    bool resolved{};
+    AssociationList associations{};
+
+    a(id, severity, timestamp, message,
+      additionalData, associations, resolved);
+
+    e.id(id);
+    e.severity(severity);
+    e.timestamp(timestamp);
+    e.message(message);
+    e.additionalData(additionalData);
+    e.sdbusplus::xyz::openbmc_project::
+        Logging::server::Entry::resolved(resolved);
+    e.associations(associations);
+}
+
+/** @brief Serialize and persist error d-bus object
+ *  @param[in] a - const reference to error entry.
+ *  @param[in] dir - pathname of directory where the serialized error will
+ *                   be placed.
+ *  @return fs::path - pathname of persisted error file
+ */
+fs::path serialize(const Entry& e,
+                   const fs::path& dir = fs::path(ERRLOG_PERSIST_PATH));
+
+/** @brief Deserialze a persisted error into a d-bus object
+ *  @param[in] path - pathname of persisted error file
+ *  @param[in] e - reference to error object which is the target of
+ *             deserialization.
+ *  @return bool - true if the deserialization was successful, false otherwise.
+ */
+bool deserialize(const fs::path& path, Entry& e);
+
+} // namespace logging
+} // namespace phosphor