Support reading parameters automatically from the superblock in vitastor-disk {dump,write}-{meta,journal}

src/util/json_util.cpp

@@ -0,0 +1,17 @@
+// Copyright (c) Vitaliy Filippov, 2019+
+// License: VNPL-1.1 or GNU GPL-2.0+ (see README.md for details)
+
+#include "json_util.h"
+
+std::map<std::string, std::string> json_to_string_map(const json11::Json::object & config)
+{
+    std::map<std::string, std::string> bs;
+    for (auto kv: config)
+    {
+        if (kv.second.is_string())
+            bs[kv.first] = kv.second.string_value();
+        else if (!kv.second.is_null())
+            bs[kv.first] = kv.second.dump();
+    }
+    return bs;
+}