Return snapshot info as JSON

src/txdb.h

@@ -13,6 +13,7 @@
 #include <string>
 #include <utility>
 #include <vector>
+#include <univalue.h>
 
 class CBlockFileInfo;
 class CBlockIndex;
@@ -94,7 +95,7 @@ public:
     bool ReadFlag(const std::string &name, bool &fValue);
     bool LoadBlockIndexGuts();
     bool blockOnchainActive(const uint256 &hash);
-    int64_t Snapshot();
+    UniValue Snapshot();
 };
 
 #endif // BITCOIN_TXDB_H