1 files changed, 16 insertions, 1 deletions
diff --git a/src/dbwrapper.h b/src/dbwrapper.h
index 442f37b420..24ef71bfbf 100644
--- a/src/dbwrapper.h
+++ b/src/dbwrapper.h
@@ -305,7 +305,22 @@ public:
      * Return true if the database managed by this class contains no entries.
      */
     bool IsEmpty();
+
+    template<typename K>
+    size_t EstimateSize(const K& key_begin, const K& key_end) const
+    {
+        CDataStream ssKey1(SER_DISK, CLIENT_VERSION), ssKey2(SER_DISK, CLIENT_VERSION);
+        ssKey1.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
+        ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
+        ssKey1 << key_begin;
+        ssKey2 << key_end;
+        leveldb::Slice slKey1(ssKey1.data(), ssKey1.size());
+        leveldb::Slice slKey2(ssKey2.data(), ssKey2.size());
+        uint64_t size = 0;
+        leveldb::Range range(slKey1, slKey2);
+        pdb->GetApproximateSizes(&range, 1, &size);
+        return size;
+    }
 };
 
 #endif // BITCOIN_DBWRAPPER_H
-