Merge #10148: Use non-atomic flushing with block replay

176c021 [qa] Test non-atomic chainstate writes (Suhas Daftuar)
d6af06d Dont create pcoinsTip until after ReplayBlocks. (Matt Corallo)
eaca1b7 Random db flush crash simulator (Pieter Wuille)
0580ee0 Adapt memory usage estimation for flushing (Pieter Wuille)
013a56a Non-atomic flushing using the blockchain as replay journal (Pieter Wuille)
b3a279c [MOVEONLY] Move LastCommonAncestor to chain (Pieter Wuille)

Tree-SHA512: 47ccc62303f9075c44d2a914be75bd6969ff881a857a2ff1227f05ec7def6f4c71c46680c5a28cb150c814999526797dc05cf2701fde1369c06169f46eccddee

1 files changed, 11 insertions, 2 deletions

diff --git a/src/coins.h b/src/coins.h
index 077545a55b..ff7719b724 100644
--- a/src/coins.h
+++ b/src/coins.h
@@ -157,6 +157,12 @@ public:
     //! Retrieve the block hash whose state this CCoinsView currently represents
     virtual uint256 GetBestBlock() const;
 
+    //! Retrieve the range of blocks that may have been only partially written.
+    //! If the database is in a consistent state, the result is the empty vector.
+    //! Otherwise, a two-element vector is returned consisting of the new and
+    //! the old block hash, in that order.
+    virtual std::vector<uint256> GetHeadBlocks() const;
+
     //! Do a bulk modification (multiple Coin changes + BestBlock change).
     //! The passed mapCoins can be modified.
     virtual bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock);
@@ -183,6 +189,7 @@ public:
     bool GetCoin(const COutPoint &outpoint, Coin &coin) const override;
     bool HaveCoin(const COutPoint &outpoint) const override;
     uint256 GetBestBlock() const override;
+    std::vector<uint256> GetHeadBlocks() const override;
     void SetBackend(CCoinsView &viewIn);
     bool BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock) override;
     CCoinsViewCursor *Cursor() const override;
@@ -291,10 +298,12 @@ private:
 };
 
 //! Utility function to add all of a transaction's outputs to a cache.
-// It assumes that overwrites are only possible for coinbase transactions,
+// When check is false, this assumes that overwrites are only possible for coinbase transactions.
+// When check is true, the underlying view may be queried to determine whether an addition is
+// an overwrite.
 // TODO: pass in a boolean to limit these possible overwrites to known
 // (pre-BIP34) cases.
-void AddCoins(CCoinsViewCache& cache, const CTransaction& tx, int nHeight);
+void AddCoins(CCoinsViewCache& cache, const CTransaction& tx, int nHeight, bool check = false);
 
 //! Utility function to find any unspent output with a given txid.
 const Coin& AccessByTxid(const CCoinsViewCache& cache, const uint256& txid);