From 9c939fab6328d50942fb6cefa15db73e2795e46c Mon Sep 17 00:00:00 2001
From: Alex Beregszaszi <alex@rtfs.hu>
Date: Thu, 11 Jan 2018 17:41:36 +0000
Subject: [PATCH] EEI: charge for memory gas cost in useGas

---
 src/eei.cpp | 2 ++
 src/eei.h   | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/src/eei.cpp b/src/eei.cpp
index 8b7eb730c..1e4346fa3 100644
--- a/src/eei.cpp
+++ b/src/eei.cpp
@@ -198,6 +198,8 @@ string toHex(evmc_uint256be const& value) {
       HERA_DEBUG << "useGas " << gas << "\n";
 
       takeGas(gas);
+      // FIXME: this may overflow
+      takeGas(gas * memory.size() / GasSchedule::memoryPageSize * GasSchedule::memoryCostPerPage);
 
       return Literal();
     }
diff --git a/src/eei.h b/src/eei.h
index 5982eb977..f3cfff99c 100644
--- a/src/eei.h
+++ b/src/eei.h
@@ -99,9 +99,13 @@ struct EthereumInterface : ShellExternalInterface {
   evmc_message const& msg;
   std::vector<uint8_t> lastReturnData;
   ExecutionResult & result;
+
 };
 
 struct GasSchedule {
+  static constexpr unsigned memoryPageSize = 65536;
+  static constexpr unsigned memoryCostPerPage = 1;
+
   static constexpr unsigned storageLoad = 200;
   static constexpr unsigned storageStoreCreate = 20000;
   static constexpr unsigned storageStoreChange = 5000;