coinstats: Extract hash_type in-member to in-param

Currently, CCoinsStats is a struct with both in-params and out-params
where the hash_type and index_requested members are the only in-params.

This change removes CCoinsStats' hash_type in-param member and adds it
to the relevant functions instead.

[META] In subsequent commits, all of CCoinsStats' members which serve as
       in-params will be moved out so as to make CCoinsStats a pure
       out-param struct.

2 files changed, 8 insertions, 13 deletions

diff --git a/src/node/coinstats.cpp b/src/node/coinstats.cpp
index eed43a1bc7..8d94e1bd36 100644
--- a/src/node/coinstats.cpp
+++ b/src/node/coinstats.cpp
@@ -93,7 +93,7 @@ static void ApplyStats(CCoinsStats& stats, const uint256& hash, const std::map<u
 
 //! Calculate statistics about the unspent transaction output set
 template <typename T>
-static bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats& stats, T hash_obj, const std::function<void()>& interruption_point, const CBlockIndex* pindex)
+static bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats& stats, T hash_obj, const std::function<void()>& interruption_point, const CBlockIndex* pindex, CoinStatsHashType& hash_type)
 {
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
     assert(pcursor);
@@ -106,7 +106,7 @@ static bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats&
     stats.hashBlock = pindex->GetBlockHash();
 
     // Use CoinStatsIndex if it is requested and available and a hash_type of Muhash or None was requested
-    if ((stats.m_hash_type == CoinStatsHashType::MUHASH || stats.m_hash_type == CoinStatsHashType::NONE) && g_coin_stats_index && stats.index_requested) {
+    if ((hash_type == CoinStatsHashType::MUHASH || hash_type == CoinStatsHashType::NONE) && g_coin_stats_index && stats.index_requested) {
         stats.index_used = true;
         return g_coin_stats_index->LookUpStats(pindex, stats);
     }
@@ -144,19 +144,19 @@ static bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats&
     return true;
 }
 
-bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats& stats, const std::function<void()>& interruption_point, const CBlockIndex* pindex)
+bool GetUTXOStats(CCoinsView* view, BlockManager& blockman, CCoinsStats& stats, CoinStatsHashType hash_type, const std::function<void()>& interruption_point, const CBlockIndex* pindex)
 {
-    switch (stats.m_hash_type) {
+    switch (hash_type) {
     case(CoinStatsHashType::HASH_SERIALIZED): {
         CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
-        return GetUTXOStats(view, blockman, stats, ss, interruption_point, pindex);
+        return GetUTXOStats(view, blockman, stats, ss, interruption_point, pindex, hash_type);
     }
     case(CoinStatsHashType::MUHASH): {
         MuHash3072 muhash;
-        return GetUTXOStats(view, blockman, stats, muhash, interruption_point, pindex);
+        return GetUTXOStats(view, blockman, stats, muhash, interruption_point, pindex, hash_type);
     }
     case(CoinStatsHashType::NONE): {
-        return GetUTXOStats(view, blockman, stats, nullptr, interruption_point, pindex);
+        return GetUTXOStats(view, blockman, stats, nullptr, interruption_point, pindex, hash_type);
     }
     } // no default case, so the compiler can warn about missing cases
     assert(false);
diff --git a/src/node/coinstats.h b/src/node/coinstats.h
index aa771b18b0..ee3f3b0030 100644
--- a/src/node/coinstats.h
+++ b/src/node/coinstats.h
@@ -28,9 +28,6 @@ enum class CoinStatsHashType {
 };
 
 struct CCoinsStats {
-    //! Which hash type to use
-    const CoinStatsHashType m_hash_type;
-
     int nHeight{0};
     uint256 hashBlock{};
     uint64_t nTransactions{0};
@@ -69,12 +66,10 @@ struct CCoinsStats {
     CAmount total_unspendables_scripts{0};
     //! Total cumulative amount of coins lost due to unclaimed miner rewards up to and including this block
     CAmount total_unspendables_unclaimed_rewards{0};
-
-    CCoinsStats(CoinStatsHashType hash_type) : m_hash_type(hash_type) {}
 };
 
 //! Calculate statistics about the unspent transaction output set
-bool GetUTXOStats(CCoinsView* view, node::BlockManager& blockman, CCoinsStats& stats, const std::function<void()>& interruption_point = {}, const CBlockIndex* pindex = nullptr);
+bool GetUTXOStats(CCoinsView* view, node::BlockManager& blockman, CCoinsStats& stats, CoinStatsHashType hash_type, const std::function<void()>& interruption_point = {}, const CBlockIndex* pindex = nullptr);
 
 uint64_t GetBogoSize(const CScript& script_pub_key);