From 4d44c773c672829cd00f2badfad614ac5bed4cb4 Mon Sep 17 00:00:00 2001
From: Jianping Wu <jianpingw@gmail.com>
Date: Thu, 7 Mar 2019 22:07:49 -0800
Subject: [PATCH] WIP: Fixed extra field deserialization.

---
 .../cryptonote_format_utils.cpp               | 18 +++++++----
 src/rpc/mining.cpp                            | 30 +++++++++----------
 2 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/src/cn_utils/cryptonote_basic/cryptonote_format_utils.cpp b/src/cn_utils/cryptonote_basic/cryptonote_format_utils.cpp
index 135e1a2e3..a7bdb0395 100644
--- a/src/cn_utils/cryptonote_basic/cryptonote_format_utils.cpp
+++ b/src/cn_utils/cryptonote_basic/cryptonote_format_utils.cpp
@@ -594,12 +594,18 @@ namespace cryptonote
   //---------------------------------------------------------------
   bool append_keva_block_to_extra(std::vector<uint8_t>& tx_extra, const tx_extra_keva_block& keva_block)
   {
-    blobdata blob;
-    if (!t_serializable_object_to_blob(keva_block, blob))
-      return false;
-
-    tx_extra.push_back(TX_EXTRA_KEVA_BLOCK_TAG);
-    std::copy(reinterpret_cast<const uint8_t*>(blob.data()), reinterpret_cast<const uint8_t*>(blob.data() + blob.size()), std::back_inserter(tx_extra));
+    // convert to variant
+    tx_extra_field field = tx_extra_keva_block{ keva_block };
+    // serialize
+    std::ostringstream oss;
+    binary_archive<true> ar(oss);
+    bool r = ::do_serialize(ar, field);
+    CHECK_AND_NO_ASSERT_MES_L1(r, false, "failed to serialize tx extra keva block");
+    // append
+    std::string tx_extra_str = oss.str();
+    size_t pos = tx_extra.size();
+    tx_extra.resize(tx_extra.size() + tx_extra_str.size());
+    memcpy(&tx_extra[pos], tx_extra_str.data(), tx_extra_str.size());
     return true;
   }
   //---------------------------------------------------------------
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index d45456489..d8a9c43d1 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -928,6 +928,20 @@ UniValue getblocktemplate(const JSONRPCRequest& request)
     }
     cn_block.miner_tx = miner_tx;
 
+    // No transactions other than coinbase.
+    cn_block.tx_hashes.clear();
+
+    // Copy keva block to extra so that we can use it in submitblock.
+    CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
+    stream << *pblock;
+    std::string kevaBlockData = stream.str();
+    cryptonote::tx_extra_keva_block extra_keva_block;
+    extra_keva_block.keva_block = kevaBlockData;
+    if (!cryptonote::append_keva_block_to_extra(cn_block.miner_tx.extra, extra_keva_block)) {
+        throw JSONRPCError(RPC_INTERNAL_ERROR, "Internal error: failed to add block");
+    }
+
+    // Now cn_block is finalized, we can calculate the reserved offset position.
     cryptonote::blobdata block_blob = cryptonote::t_serializable_object_to_blob(cn_block);
     crypto::public_key tx_pub_key = cryptonote::get_tx_pub_key_from_extra(cn_block.miner_tx);
     if(tx_pub_key == crypto::null_pkey) {
@@ -942,21 +956,7 @@ UniValue getblocktemplate(const JSONRPCRequest& request)
     {
       throw JSONRPCError(RPC_INTERNAL_ERROR, "Internal error: Failed to calculate offset");
     }
-
-    // No transactions other than coinbase.
-    cn_block.tx_hashes.clear();
-
-    // Copy keva block to extra so that we can use it in submitblock.
-    CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
-    stream << *pblock;
-    std::string kevaBlockData = HexStr(stream.begin(), stream.end());
-    cryptonote::tx_extra_keva_block extra_keva_block;
-    extra_keva_block.keva_block = kevaBlockData;
-    if (!cryptonote::append_keva_block_to_extra(cn_block.miner_tx.extra, extra_keva_block)) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Internal error: failed to add block");
-    }
-    cryptonote::blobdata template_blob = cryptonote::block_to_blob(cn_block);
-    std::string hex_template_blob = HexStr(template_blob.begin(), template_blob.end());
+    std::string hex_template_blob = HexStr(block_blob.begin(), block_blob.end());
 
     UniValue result(UniValue::VOBJ);
     const uint64_t difficulty = ConvertNBitsToDiff(pblock->nBits);