Add support for log-handler

This handler is based off of version handler with major differences in
handler_builder

Tested:
created the blackbox blob successfully using this lib.
Read the data from the blob using a host side tool

Signed-off-by: Gaurav Gandhi <gauravgandhi@google.com>
Change-Id: I9ef775af752156a1647453ff3831ef4c0449d546
diff --git a/bmc/log-handler/log_handlers_builder.hpp b/bmc/log-handler/log_handlers_builder.hpp
new file mode 100644
index 0000000..552758d
--- /dev/null
+++ b/bmc/log-handler/log_handlers_builder.hpp
@@ -0,0 +1,35 @@
+// Copyright 2021 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+#include "buildjson.hpp"
+#include "log_handler.hpp"
+
+#include <nlohmann/json.hpp>
+
+#include <vector>
+
+namespace ipmi_flash
+{
+/**
+ * provide the method to parse and validate blob entries from json and produce
+ * something that is usable by the log handler.
+ */
+class LogHandlersBuilder : public HandlersBuilderIfc<LogBlobHandler::ActionPack>
+{
+  public:
+    std::vector<HandlerConfig<LogBlobHandler::ActionPack>>
+        buildHandlerFromJson(const nlohmann::json& data) override;
+};
+} // namespace ipmi_flash