1 files changed, 29 insertions, 8 deletions

diff --git a/src/validation.h b/src/validation.h
index 99850f71d9..96d249b6d3 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -211,7 +211,7 @@ static const uint64_t MIN_DISK_SPACE_FOR_BLOCK_FILES = 550 * 1024 * 1024;
  * @param[in]   pblock  The block we want to process.
  * @param[in]   fForceProcessing Process this block even if unrequested; used for non-network block sources and whitelisted peers.
  * @param[out]  fNewBlock A boolean which is set to indicate if the block was first received via this call
- * @return True if state.IsValid()
+ * @returns     If the block was processed, independently of block validity
  */
 bool ProcessNewBlock(const CChainParams& chainparams, const std::shared_ptr<const CBlock> pblock, bool fForceProcessing, bool* fNewBlock) LOCKS_EXCLUDED(cs_main);
 
@@ -240,8 +240,6 @@ bool LoadGenesisBlock(const CChainParams& chainparams);
 /** Load the block tree and coins database from disk,
  * initializing state if we're running with -reindex. */
 bool LoadBlockIndex(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
-/** Update the chain tip based on database information. */
-bool LoadChainTip(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 /** Unload database information */
 void UnloadBlockIndex();
 /** Run an instance of the script checking thread */
@@ -386,6 +384,9 @@ bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& pa
 /** When there are blocks in the active chain with missing data, rewind the chainstate and remove them from the block index */
 bool RewindBlockIndex(const CChainParams& params) LOCKS_EXCLUDED(cs_main);
 
+/** Compute at which vout of the block's coinbase transaction the witness commitment occurs, or -1 if not found */
+int GetWitnessCommitmentIndex(const CBlock& block);
+
 /** Update uncommitted block structures (currently: only the witness reserved value). This is safe for submitted blocks. */
 void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
 
@@ -400,9 +401,6 @@ public:
     bool VerifyDB(const CChainParams& chainparams, CCoinsView *coinsview, int nCheckLevel, int nCheckDepth);
 };
 
-/** Replay blocks that aren't fully applied to the database. */
-bool ReplayBlocks(const CChainParams& params, CCoinsView* view);
-
 CBlockIndex* LookupBlockIndex(const uint256& hash) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
 /** Find the last common block between the parameter chain and a locator. */
@@ -653,6 +651,8 @@ public:
      *
      * If FlushStateMode::NONE is used, then FlushStateToDisk(...) won't do anything
      * besides checking if we need to prune.
+     *
+     * @returns true unless a system error occurred
      */
     bool FlushStateToDisk(
         const CChainParams& chainparams,
@@ -667,7 +667,24 @@ public:
     //! if we pruned.
     void PruneAndFlush();
 
-    bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams, std::shared_ptr<const CBlock> pblock) LOCKS_EXCLUDED(cs_main);
+    /**
+     * Make the best chain active, in multiple steps. The result is either failure
+     * or an activated best chain. pblock is either nullptr or a pointer to a block
+     * that is already loaded (to avoid loading it again from disk).
+     *
+     * ActivateBestChain is split into steps (see ActivateBestChainStep) so that
+     * we avoid holding cs_main for an extended period of time; the length of this
+     * call may be quite long during reindexing or a substantial reorg.
+     *
+     * May not be called with cs_main held. May not be called in a
+     * validationinterface callback.
+     *
+     * @returns true unless a system error occurred
+     */
+    bool ActivateBestChain(
+        CValidationState& state,
+        const CChainParams& chainparams,
+        std::shared_ptr<const CBlock> pblock) LOCKS_EXCLUDED(cs_main);
 
     bool AcceptBlock(const std::shared_ptr<const CBlock>& pblock, CValidationState& state, const CChainParams& chainparams, CBlockIndex** ppindex, bool fRequested, const FlatFilePos* dbp, bool* fNewBlock) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
@@ -684,7 +701,8 @@ public:
     bool InvalidateBlock(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindex) LOCKS_EXCLUDED(cs_main);
     void ResetBlockFailureFlags(CBlockIndex* pindex) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
 
-    bool ReplayBlocks(const CChainParams& params, CCoinsView* view);
+    /** Replay blocks that aren't fully applied to the database. */
+    bool ReplayBlocks(const CChainParams& params);
     bool RewindBlockIndex(const CChainParams& params) LOCKS_EXCLUDED(cs_main);
     bool LoadGenesisBlock(const CChainParams& chainparams);
 
@@ -702,6 +720,9 @@ public:
      */
     void CheckBlockIndex(const Consensus::Params& consensusParams);
 
+    /** Update the chain tip based on database information, i.e. CoinsTip()'s best block. */
+    bool LoadChainTip(const CChainParams& chainparams) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
+
 private:
     bool ActivateBestChainStep(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexMostWork, const std::shared_ptr<const CBlock>& pblock, bool& fInvalidFound, ConnectTrace& connectTrace) EXCLUSIVE_LOCKS_REQUIRED(cs_main, ::mempool.cs);
     bool ConnectTip(CValidationState& state, const CChainParams& chainparams, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions& disconnectpool) EXCLUSIVE_LOCKS_REQUIRED(cs_main, ::mempool.cs);