1 files changed, 18 insertions, 16 deletions

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index abab731ea7..75677a722b 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -78,15 +78,22 @@ double GetDifficulty(const CBlockIndex* blockindex)
     return dDiff;
 }
 
-UniValue blockheaderToJSON(const CBlockIndex* blockindex)
+static int ComputeNextBlockAndDepth(const CBlockIndex* tip, const CBlockIndex* blockindex, const CBlockIndex*& next)
+{
+    next = tip->GetAncestor(blockindex->nHeight + 1);
+    if (next && next->pprev == blockindex) {
+        return tip->nHeight - blockindex->nHeight + 1;
+    }
+    next = nullptr;
+    return blockindex == tip ? 1 : -1;
+}
+
+UniValue blockheaderToJSON(const CBlockIndex* tip, const CBlockIndex* blockindex)
 {
-    AssertLockHeld(cs_main);
     UniValue result(UniValue::VOBJ);
     result.pushKV("hash", blockindex->GetBlockHash().GetHex());
-    int confirmations = -1;
-    // Only report confirmations if the block is on the main chain
-    if (chainActive.Contains(blockindex))
-        confirmations = chainActive.Height() - blockindex->nHeight + 1;
+    const CBlockIndex* pnext;
+    int confirmations = ComputeNextBlockAndDepth(tip, blockindex, pnext);
     result.pushKV("confirmations", confirmations);
     result.pushKV("height", blockindex->nHeight);
     result.pushKV("version", blockindex->nVersion);
@@ -102,21 +109,17 @@ UniValue blockheaderToJSON(const CBlockIndex* blockindex)
 
     if (blockindex->pprev)
         result.pushKV("previousblockhash", blockindex->pprev->GetBlockHash().GetHex());
-    CBlockIndex *pnext = chainActive.Next(blockindex);
     if (pnext)
         result.pushKV("nextblockhash", pnext->GetBlockHash().GetHex());
     return result;
 }
 
-UniValue blockToJSON(const CBlock& block, const CBlockIndex* blockindex, bool txDetails)
+UniValue blockToJSON(const CBlock& block, const CBlockIndex* tip, const CBlockIndex* blockindex, bool txDetails)
 {
-    AssertLockHeld(cs_main);
     UniValue result(UniValue::VOBJ);
     result.pushKV("hash", blockindex->GetBlockHash().GetHex());
-    int confirmations = -1;
-    // Only report confirmations if the block is on the main chain
-    if (chainActive.Contains(blockindex))
-        confirmations = chainActive.Height() - blockindex->nHeight + 1;
+    const CBlockIndex* pnext;
+    int confirmations = ComputeNextBlockAndDepth(tip, blockindex, pnext);
     result.pushKV("confirmations", confirmations);
     result.pushKV("strippedsize", (int)::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS));
     result.pushKV("size", (int)::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION));
@@ -148,7 +151,6 @@ UniValue blockToJSON(const CBlock& block, const CBlockIndex* blockindex, bool tx
 
     if (blockindex->pprev)
         result.pushKV("previousblockhash", blockindex->pprev->GetBlockHash().GetHex());
-    CBlockIndex *pnext = chainActive.Next(blockindex);
     if (pnext)
         result.pushKV("nextblockhash", pnext->GetBlockHash().GetHex());
     return result;
@@ -744,7 +746,7 @@ static UniValue getblockheader(const JSONRPCRequest& request)
         return strHex;
     }
 
-    return blockheaderToJSON(pblockindex);
+    return blockheaderToJSON(chainActive.Tip(), pblockindex);
 }
 
 static CBlock GetBlockChecked(const CBlockIndex* pblockindex)
@@ -845,7 +847,7 @@ static UniValue getblock(const JSONRPCRequest& request)
         return strHex;
     }
 
-    return blockToJSON(block, pblockindex, verbosity >= 2);
+    return blockToJSON(block, chainActive.Tip(), pblockindex, verbosity >= 2);
 }
 
 struct CCoinsStats