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, 19 insertions, 0 deletions

diff --git a/src/chain.cpp b/src/chain.cpp
index 8d4c4e7dea..ffd58d471d 100644
--- a/src/chain.cpp
+++ b/src/chain.cpp
@@ -148,3 +148,22 @@ int64_t GetBlockProofEquivalentTime(const CBlockIndex& to, const CBlockIndex& fr
     }
     return sign * r.GetLow64();
 }
+
+/** Find the last common ancestor two blocks have.
+ *  Both pa and pb must be non-NULL. */
+const CBlockIndex* LastCommonAncestor(const CBlockIndex* pa, const CBlockIndex* pb) {
+    if (pa->nHeight > pb->nHeight) {
+        pa = pa->GetAncestor(pb->nHeight);
+    } else if (pb->nHeight > pa->nHeight) {
+        pb = pb->GetAncestor(pa->nHeight);
+    }
+
+    while (pa != pb && pa && pb) {
+        pa = pa->pprev;
+        pb = pb->pprev;
+    }
+
+    // Eventually all chain branches meet at the genesis block.
+    assert(pa == pb);
+    return pa;
+}