From 06816dd73eafdb8cff7e2e6fde014c3989da7253 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Thu, 10 Nov 2011 21:15:32 -0800
Subject: [PATCH] The low-level code that manages a tree of hash nodes. This
 manages the individual nodes but not the logic that connects them. It is
 designed around the assumption that not all nodes are necessarily resident in
 memory.

---
 SHAMap.h | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)
 create mode 100644 SHAMap.h

diff --git a/SHAMap.h b/SHAMap.h
new file mode 100644
index 0000000000..62d2d1bea3
--- /dev/null
+++ b/SHAMap.h
@@ -0,0 +1,88 @@
+#ifndef __SHAMAP__
+#define __SHAMAP__
+
+#include "uint256.h"
+
+class SHAMapNodeID
+{
+public:
+	int	mDepth;
+	uint256	mNodeID;
+	
+        bool operator<(const Transaction &) const;
+        bool operator>(const Transaction &) const;
+        bool operator==(const Transaction &) const;
+        bool operator!=(const Transaction &) const;
+        bool operator<=(const Transaction &) const;
+        bool operator>=(const Transaction &) const;
+};
+
+class SHAMapLeafNode
+{
+private:
+	uint256			mNodeID;
+	std::list<uint256>	mHashes;
+	uint256			mNodeHash;
+
+public:
+	SHAMapLeafNode(const uint256& NodeID);
+
+	const uint256& GetNodeID(void) const { return mNodeID; }
+	bool HasHash(const uint256& Hash) const;
+
+	uint256& GetNodeHash();
+
+	bool AddHash(const uint256& Hash);
+	bool DelHash(const uint256& Hash);
+};
+
+typedef boost::shared_ptr<SHAMapLeafNode> pointer;
+
+class SHAMapInnerNode
+{
+private:
+	int		mDepth;
+	uint256		mNodeID;
+	uint256		mHash;
+	uint256[32]	mHashes;
+
+public:
+	SHAMapInnerNode(int Depth, const uint256 &NodeID);
+
+	int GetDepth() const { return mDepth; }
+	const uint256& GetNodeID() const { return mNodeID; }
+	const uint256& GetChildHash(int m) const;
+	const uint256& GetNodeHash() const;
+
+	bool IsRootNode() const { return mDepth==0; }
+	bool IsLastInnerNode() const { return mDepth==9; }
+
+	uint256 GetChildNodeID(int m) const;
+	void SetChildHash(int m, const uint256& Hash);
+	void SetChildHash(const SHAMapInnerNode &mChild);
+	void SetChildHash(const SHAMapLeafNode &mLeaf);
+};
+
+typedef boost::shared_ptr<SHAMapInnerNode> pointer;
+
+// Not all nodes need to be resident in memory, the class can hold subsets
+// This class does not handle any inter-node logic because that requires reads/writes
+
+class SHAMap
+{
+private:
+	boost::mutex mLock;
+	std::map<SHAMapNodeID, SHAMapLeafNode> mLeaves
+	std::multimap<SHAMapNodeID, SHAMapInnerNode> mInnerNodes;
+
+public:
+	SHAMap();
+
+	bool HasInnerNode(int m, const uint160 &nodeID);
+	bool GiveInnerNode(SHAMapInnerNode::pointer);
+	SHAMapInnerNode::pointer GetInnerNode(int m, const uint160 &nodeID);
+
+	bool HasLeafNode(int m, const uint160 &nodeID);
+	bool GiveLeafNode(SHAMapLeafNode::pointer);
+	SHAMapLeafNode::pointer GetLeafNode(int m, const uint160 &nodeID);
+};