rpc: gettxoutsetinfo can specify hash_type (only legacy option for now)

2 files changed, 38 insertions, 8 deletions

diff --git a/src/node/coinstats.cpp b/src/node/coinstats.cpp
index faa62420cd..cc5e3cb627 100644
--- a/src/node/coinstats.cpp
+++ b/src/node/coinstats.cpp
@@ -24,7 +24,7 @@ static uint64_t GetBogoSize(const CScript& scriptPubKey)
            scriptPubKey.size() /* scriptPubKey */;
 }
 
-static void ApplyStats(CCoinsStats &stats, CHashWriter& ss, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
+static void ApplyStats(CCoinsStats& stats, CHashWriter& ss, const uint256& hash, const std::map<uint32_t, Coin>& outputs)
 {
     assert(!outputs.empty());
     ss << hash;
@@ -42,19 +42,21 @@ static void ApplyStats(CCoinsStats &stats, CHashWriter& ss, const uint256& hash,
 }
 
 //! Calculate statistics about the unspent transaction output set
-bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void()>& interruption_point)
+template <typename T>
+static bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, T hash_obj, const std::function<void()>& interruption_point)
 {
     stats = CCoinsStats();
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
     assert(pcursor);
 
-    CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
     stats.hashBlock = pcursor->GetBestBlock();
     {
         LOCK(cs_main);
         stats.nHeight = LookupBlockIndex(stats.hashBlock)->nHeight;
     }
-    ss << stats.hashBlock;
+
+    PrepareHash(hash_obj, stats);
+
     uint256 prevkey;
     std::map<uint32_t, Coin> outputs;
     while (pcursor->Valid()) {
@@ -63,7 +65,7 @@ bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void
         Coin coin;
         if (pcursor->GetKey(key) && pcursor->GetValue(coin)) {
             if (!outputs.empty() && key.hash != prevkey) {
-                ApplyStats(stats, ss, prevkey, outputs);
+                ApplyStats(stats, hash_obj, prevkey, outputs);
                 outputs.clear();
             }
             prevkey = key.hash;
@@ -75,9 +77,33 @@ bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void
         pcursor->Next();
     }
     if (!outputs.empty()) {
-        ApplyStats(stats, ss, prevkey, outputs);
+        ApplyStats(stats, hash_obj, prevkey, outputs);
     }
-    stats.hashSerialized = ss.GetHash();
+
+    FinalizeHash(hash_obj, stats);
+
     stats.nDiskSize = view->EstimateSize();
     return true;
 }
+
+bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, CoinStatsHashType hash_type, const std::function<void()>& interruption_point)
+{
+    switch (hash_type) {
+    case(CoinStatsHashType::HASH_SERIALIZED): {
+        CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
+        return GetUTXOStats(view, stats, ss, interruption_point);
+    }
+    } // no default case, so the compiler can warn about missing cases
+    assert(false);
+}
+
+// The legacy hash serializes the hashBlock
+static void PrepareHash(CHashWriter& ss, CCoinsStats& stats)
+{
+    ss << stats.hashBlock;
+}
+
+static void FinalizeHash(CHashWriter& ss, CCoinsStats& stats)
+{
+    stats.hashSerialized = ss.GetHash();
+}
diff --git a/src/node/coinstats.h b/src/node/coinstats.h
index d9cdaa3036..1d0270d56d 100644
--- a/src/node/coinstats.h
+++ b/src/node/coinstats.h
@@ -14,6 +14,10 @@
 
 class CCoinsView;
 
+enum class CoinStatsHashType {
+    HASH_SERIALIZED,
+};
+
 struct CCoinsStats
 {
     int nHeight{0};
@@ -30,6 +34,6 @@ struct CCoinsStats
 };
 
 //! Calculate statistics about the unspent transaction output set
-bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const std::function<void()>& interruption_point = {});
+bool GetUTXOStats(CCoinsView* view, CCoinsStats& stats, const CoinStatsHashType hash_type, const std::function<void()>& interruption_point = {});
 
 #endif // BITCOIN_NODE_COINSTATS_H