1 files changed, 9 insertions, 0 deletions
diff --git a/src/primitives/block.cpp b/src/primitives/block.cpp
index 6fb33230a5..df900388f2 100644
--- a/src/primitives/block.cpp
+++ b/src/primitives/block.cpp
@@ -31,3 +31,12 @@ std::string CBlock::ToString() const
     }
     return s.str();
 }
+
+int64_t GetBlockCost(const CBlock& block)
+{
+    // This implements the cost = (stripped_size * 4) + witness_size formula,
+    // using only serialization with and without witness data. As witness_size
+    // is equal to total_size - stripped_size, this formula is identical to:
+    // cost = (stripped_size * 3) + total_size.
+    return ::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * (WITNESS_SCALE_FACTOR - 1) + ::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION);
+}