From 30da90de8dcbb62199262f65516e574dab57d1bd Mon Sep 17 00:00:00 2001
From: Matt Corallo <git@bluematt.me>
Date: Sat, 1 Nov 2014 23:53:55 -0700
Subject: [PATCH] Add CMerkleBlock constructor for tx set + block and an empty
 one

---
 src/merkleblock.cpp | 23 +++++++++++++++++++++++
 src/merkleblock.h   |  5 +++++
 2 files changed, 28 insertions(+)

diff --git a/src/merkleblock.cpp b/src/merkleblock.cpp
index b51b002b9..40723f032 100644
--- a/src/merkleblock.cpp
+++ b/src/merkleblock.cpp
@@ -37,6 +37,29 @@ CMerkleBlock::CMerkleBlock(const CBlock& block, CBloomFilter& filter)
     txn = CPartialMerkleTree(vHashes, vMatch);
 }
 
+CMerkleBlock::CMerkleBlock(const CBlock& block, const std::set<uint256>& txids)
+{
+    header = block.GetBlockHeader();
+
+    vector<bool> vMatch;
+    vector<uint256> vHashes;
+
+    vMatch.reserve(block.vtx.size());
+    vHashes.reserve(block.vtx.size());
+
+    for (unsigned int i = 0; i < block.vtx.size(); i++)
+    {
+        const uint256& hash = block.vtx[i].GetHash();
+        if (txids.count(hash))
+            vMatch.push_back(true);
+        else
+            vMatch.push_back(false);
+        vHashes.push_back(hash);
+    }
+
+    txn = CPartialMerkleTree(vHashes, vMatch);
+}
+
 uint256 CPartialMerkleTree::CalcHash(int height, unsigned int pos, const std::vector<uint256> &vTxid) {
     if (height == 0) {
         // hash at height 0 is the txids themself
diff --git a/src/merkleblock.h b/src/merkleblock.h
index 52c914967..d90face17 100644
--- a/src/merkleblock.h
+++ b/src/merkleblock.h
@@ -139,6 +139,11 @@ public:
      */
     CMerkleBlock(const CBlock& block, CBloomFilter& filter);
 
+    // Create from a CBlock, matching the txids in the set
+    CMerkleBlock(const CBlock& block, const std::set<uint256>& txids);
+
+    CMerkleBlock() {}
+
     ADD_SERIALIZE_METHODS;
 
     template <typename Stream, typename Operation>