Debug and unit test code. Copy on write logic. Bugfixes.

2025-11-19 18:15:50 +00:00 · 2011-11-25 00:03:33 -08:00
parent 83b2f8b73a
commit 0df9ec91fa
3 changed files with 192 additions and 63 deletions
--- a/SHAMap.cpp
+++ b/SHAMap.cpp
@@ -4,16 +4,22 @@

 #include <boost/foreach.hpp>

-SHAMap::SHAMap()
+SHAMap::SHAMap() : mSeq(0)
 {
- ;
+	root=SHAMapInnerNode::pointer(new SHAMapInnerNode(SHAMapNode(SHAMapNode::rootDepth, uint256()), mSeq));
 }

 void SHAMap::dirtyUp(const uint256& id)
 { // walk the tree up from through the inner nodes to the root
  // update linking hashes and add nodes to dirty list
+#ifdef DEBUG
+	std::cerr << "dirtyUp(" << id.GetHex() << ")" << std::endl;
+#endif
 	SHAMapLeafNode::pointer leaf=mLeafByID[SHAMapNode(SHAMapNode::leafDepth, id)];
 	if(!leaf) throw SHAMapException(MissingNode);
+#ifdef DEBUG
+	std::cerr << "found leaf " << leaf->getString() << std::endl;
+#endif

 	uint256 hVal=leaf->getNodeHash();
 	if(mDirtyLeafNodes) (*mDirtyLeafNodes)[*leaf]=leaf;
@@ -21,6 +27,9 @@ void SHAMap::dirtyUp(const uint256& id)

 	for(int depth=SHAMapNode::leafDepth-1; depth>=0; depth--)
 	{ // walk up the tree to the root updating nodes
+#ifdef DEBUG
+		std::cerr << "walk up to " << depth << ", " << leaf->getNodeID().GetHex() << std::endl;
+#endif
 		SHAMapInnerNode::pointer node=mInnerNodeByID[SHAMapNode(depth, leaf->getNodeID())];
 		if(!node) throw SHAMapException(MissingNode);
 		if(!node->setChildHash(node->selectBranch(id), hVal)) return;
@@ -37,11 +46,17 @@ SHAMapLeafNode::pointer SHAMap::checkCacheLeaf(const SHAMapNode& iNode)
 }


-SHAMapLeafNode::pointer SHAMap::walkToLeaf(const uint256& id, bool create)
+SHAMapLeafNode::pointer SHAMap::walkToLeaf(const uint256& id, bool create, bool modify)
 { // walk down to the leaf that would contain this ID
 	// is leaf node in cache
+#ifdef DEBUG
+	std::cerr << "walkToLeaf(" << id.GetHex() << ")";
+	if(create) std::cerr << " create";
+	if(modify) std::cerr << " modify";
+	std::cerr << std::endl;
+#endif
 	SHAMapLeafNode::pointer ln=checkCacheLeaf(SHAMapNode(SHAMapNode::leafDepth, id));
-	if(ln) return ln;
+	if(ln) return returnLeaf(ln, modify);

 	// walk tree to leaf
 	SHAMapInnerNode::pointer inNode=root;
@@ -53,66 +68,99 @@ SHAMapLeafNode::pointer SHAMap::walkToLeaf(const uint256& id, bool create)
 			throw SHAMapException(InvalidNode);
 		if(inNode->isEmptyBranch(branch))
 		{ // no nodes below this one
+#ifdef DEBUG
+			std::cerr << "No nodes below level " << i << std::endl;
+#endif
 			if(!create) return SHAMapLeafNode::pointer();
 			return createLeaf(*inNode, id);
 		}
 		if(i!=(SHAMapNode::leafDepth)-1)
 		{ // child is another inner node
-			inNode=getInner(inNode->getChildNodeID(branch), inNode->getChildHash(branch));
+			inNode=getInner(inNode->getChildNodeID(branch), inNode->getChildHash(branch), modify);
 			if(inNode==NULL) throw SHAMapException(InvalidNode);
 		}
 		else // child is leaf node
 		{
-			ln=getLeaf(inNode->getChildNodeID(branch), inNode->getChildHash(branch));
+			ln=getLeaf(inNode->getChildNodeID(branch), inNode->getChildHash(branch), modify);
 			if(ln==NULL)
 			{
-				if(!create) return SHAMapLeafNode::pointer();
+ 				if(!create) return SHAMapLeafNode::pointer();
 				return createLeaf(*inNode, id);
 			}
 		}
 	}
 	
-	return ln;
+	return returnLeaf(ln, modify);
 }

-SHAMapLeafNode::pointer SHAMap::getLeaf(const SHAMapNode &id, const uint256& hash)
+SHAMapLeafNode::pointer SHAMap::getLeaf(const SHAMapNode &id, const uint256& hash, bool modify)
 { // retrieve a leaf whose node hash is known
+#ifdef DEBUG
+	std::cerr << "getLeaf(" << id.getString() << ", " << hash.GetHex() << ")";
+	if(modify) std::cerr << " modify";
+	std::cerr << std::endl;
+#endif
 	assert(!!hash);
 	if(!id.isLeaf()) return SHAMapLeafNode::pointer();

 	SHAMapLeafNode::pointer leaf=mLeafByID[id];			// is the leaf in memory
-	if(leaf) return leaf;
+	if(leaf) return returnLeaf(leaf, modify);

 	std::vector<SHAMapItem::pointer> leafData;			// is it in backing store
 	if(!fetchLeafNode(hash, id, leafData))
-		throw SHAMapException(MissingNode);
+ 		throw SHAMapException(MissingNode);

-	leaf=SHAMapLeafNode::pointer(new SHAMapLeafNode(id));
-	
+	leaf=SHAMapLeafNode::pointer(new SHAMapLeafNode(id, mSeq));
 	BOOST_FOREACH(SHAMapItem::pointer& item, leafData)
 		leaf->addUpdateItem(item);
-
 	leaf->updateHash();
 	if(leaf->getNodeHash()!=hash) throw SHAMapException(InvalidNode);
 	mLeafByID[id]=leaf;
 	return leaf;
 }

-SHAMapInnerNode::pointer SHAMap::getInner(const SHAMapNode &id, const uint256& hash)
+SHAMapInnerNode::pointer SHAMap::getInner(const SHAMapNode &id, const uint256& hash, bool modify)
 { // retrieve an inner node whose node hash is known
+#ifdef DEBUG
+	std::cerr << "getInner(" << id.getString() << ", " << hash.GetHex() << ")";
+	if(modify) std::cerr << " modify";
+	std::cerr << std::endl;
+#endif
 	SHAMapInnerNode::pointer node=mInnerNodeByID[id];
-	if(node) return node;
+	if(node) return returnNode(node, modify);
 	
 	std::vector<unsigned char> rawNode;
 	if(!fetchInnerNode(hash, id, rawNode)) throw SHAMapException(MissingNode);

-	node=SHAMapInnerNode::pointer(new SHAMapInnerNode(id, rawNode));
+	node=SHAMapInnerNode::pointer(new SHAMapInnerNode(id, rawNode, mSeq));
 	if(node->getNodeHash()!=hash) throw SHAMapException(InvalidNode);

 	mInnerNodeByID[id]=node;
 	return node;
 }

+SHAMapLeafNode::pointer SHAMap::returnLeaf(SHAMapLeafNode::pointer leaf, bool modify)
+{ // make sure the leaf is suitable for the intended operation (copy on write)
+	if(leaf && modify && (leaf->getSeq()!=mSeq))
+	{
+		leaf=SHAMapLeafNode::pointer(new SHAMapLeafNode(*leaf, mSeq));
+		mLeafByID[*leaf]=leaf;
+		if(mDirtyLeafNodes) (*mDirtyLeafNodes)[*leaf]=leaf;
+	}
+	return leaf;
+}
+
+SHAMapInnerNode::pointer SHAMap::returnNode(SHAMapInnerNode::pointer node, bool modify)
+{ // make sure the node is suitable for the intended operation (copy on write)
+	if(node && modify && (node->getSeq()!=mSeq))
+	{
+		node=SHAMapInnerNode::pointer(new SHAMapInnerNode(*node, mSeq));
+		mInnerNodeByID[*node]=node;
+		if(mDirtyInnerNodes) (*mDirtyInnerNodes)[*node]=node;
+	}
+	return node;
+}
+
 SHAMapItem::SHAMapItem(const uint256& tag, const std::vector<unsigned char>& data)
 	: mTag(tag), mData(data)
 { ; }
@@ -133,20 +181,24 @@ SHAMapItem::pointer SHAMap::peekLastItem()
 	return lastBelow(root);
 }

-SHAMapItem::pointer SHAMap::firstBelow(SHAMapInnerNode::pointer Node)
+SHAMapItem::pointer SHAMap::firstBelow(SHAMapInnerNode::pointer node)
 {
+#ifdef DEBUG
+	std::cerr << "firstBelow(" << node->getString() << ")" << std::endl;
+#endif
+
 	const uint256 zero;
 	int i;

-	while(Node->isChildLeaf())
+	while(!node->isChildLeaf())
 	{
 		for(i=0; i<32; i++)
 		{
-			uint256 cHash(Node->getChildHash(i));
+			uint256 cHash(node->getChildHash(i));
 			if(cHash!=zero)
 			{
-				Node=getInner(Node->getChildNodeID(i), cHash);
-				if(!Node) return SHAMapItem::pointer();
+				node=getInner(node->getChildNodeID(i), cHash, false);
+				if(!node) return SHAMapItem::pointer();
 				break;
 			}
 		}
@@ -155,10 +207,10 @@ SHAMapItem::pointer SHAMap::firstBelow(SHAMapInnerNode::pointer Node)
 	
 	for(int i=0; i<32; i++)
 	{
-		uint256 cHash=Node->getChildHash(i);
+		uint256 cHash=node->getChildHash(i);
 		if(cHash!=zero)
 		{
-			SHAMapLeafNode::pointer mLeaf=getLeaf(Node->getChildNodeID(i), cHash);
+			SHAMapLeafNode::pointer mLeaf=getLeaf(node->getChildNodeID(i), cHash, false);
 			if(!mLeaf) return SHAMapItem::pointer();
 			return mLeaf->firstItem();
 		}
@@ -166,22 +218,22 @@ SHAMapItem::pointer SHAMap::firstBelow(SHAMapInnerNode::pointer Node)
 	return SHAMapItem::pointer();
 }

-SHAMapItem::pointer SHAMap::lastBelow(SHAMapInnerNode::pointer Node)
+SHAMapItem::pointer SHAMap::lastBelow(SHAMapInnerNode::pointer node)
 {
 	ScopedLock sl(mLock);

 	const uint256 zero;
 	int i;

-	while(Node->isChildLeaf())
+	while(!node->isChildLeaf())
 	{
 		for(i=31; i>=0; i--)
 		{
-			uint256 cHash(Node->getChildHash(i));
+			uint256 cHash(node->getChildHash(i));
 			if(cHash!=0)
 			{
-				Node=getInner(Node->getChildNodeID(i), cHash);
-				if(!Node) return SHAMapItem::pointer();
+				node=getInner(node->getChildNodeID(i), cHash, false);
+				if(!node) return SHAMapItem::pointer();
 				break;
 			}
 		}
@@ -189,10 +241,10 @@ SHAMapItem::pointer SHAMap::lastBelow(SHAMapInnerNode::pointer Node)
 	}
 	for(int i=31; i>=0; i--)
 	{
-		uint256 cHash=Node->getChildHash(i);
+		uint256 cHash=node->getChildHash(i);
 		if(cHash!=zero)
 		{
-			SHAMapLeafNode::pointer mLeaf=getLeaf(Node->getChildNodeID(i), cHash);
+			SHAMapLeafNode::pointer mLeaf=getLeaf(node->getChildNodeID(i), cHash, false);
 			if(!mLeaf) return SHAMapItem::pointer();
 			return mLeaf->lastItem();
 		}
@@ -203,7 +255,7 @@ SHAMapItem::pointer SHAMap::peekNextItem(const uint256& id)
 { // Get a pointer to the next item in the tree after a given item - item must be in tree
 	ScopedLock sl(mLock);

-	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false, false);
 	if(!leaf) return SHAMapItem::pointer();

 	// is there another item in this leaf? (there almost never will be)
@@ -223,7 +275,7 @@ SHAMapItem::pointer SHAMap::peekNextItem(const uint256& id)
 				
 				if(nextNode.isLeaf())
 				{ // this is a terminal inner node
-					leaf=getLeaf(nextNode, nextHash);
+					leaf=getLeaf(nextNode, nextHash, false);
 					if(!leaf) throw SHAMapException(MissingNode);
 					next=leaf->firstItem();
 					if(!next) throw SHAMapException(InvalidNode);
@@ -231,7 +283,7 @@ SHAMapItem::pointer SHAMap::peekNextItem(const uint256& id)
 				}

 				// the next item is the first item below this node
-				SHAMapInnerNode::pointer inner=getInner(nextNode, nextHash);
+				SHAMapInnerNode::pointer inner=getInner(nextNode, nextHash, false);
 				if(!inner) throw SHAMapException(MissingNode);
 				next=firstBelow(inner);
 				if(!next) throw SHAMapException(InvalidNode);
@@ -250,22 +302,31 @@ SHAMapItem::pointer SHAMap::peekPrevItem(const uint256& id)

 SHAMapLeafNode::pointer SHAMap::createLeaf(const SHAMapInnerNode& lowestParent, const uint256& id)
 {
-	int depth=lowestParent.getDepth();
-	for(int depth=lowestParent.getDepth(); depth<SHAMapNode::leafDepth; depth++)
+#ifdef DEBUG
+	std::cerr << "createLeaf(" << lowestParent.getString() << std::endl;
+	std::cerr << "  for " << id.GetHex() << ")" << std::endl;
+#endif
+	assert(!!id);
+	for(int depth=lowestParent.getDepth()+1; depth<SHAMapNode::leafDepth; depth++)
 	{
-		SHAMapInnerNode::pointer newNode(new SHAMapInnerNode(SHAMapNode(++depth, id)));
+		SHAMapInnerNode::pointer newNode(new SHAMapInnerNode(SHAMapNode(depth, id), mSeq));
+#ifdef DEBUG
+		std::cerr << "create node " << newNode->getString() << std::endl;
+#endif
 		mInnerNodeByID[*newNode]=newNode;
 	}
-	
-	SHAMapLeafNode::pointer newLeaf(new SHAMapLeafNode(SHAMapNode(SHAMapNode::leafDepth, id)));
+	SHAMapLeafNode::pointer newLeaf(new SHAMapLeafNode(SHAMapNode(SHAMapNode::leafDepth, id), mSeq));
 	mLeafByID[*newLeaf]=newLeaf;
+#ifdef DEBUG
+	std::cerr << "made leaf " << newLeaf->getString() << std::endl;
+#endif
 	return newLeaf;
 }

 SHAMapItem::pointer SHAMap::peekItem(const uint256& id)
 {
 	ScopedLock sl(mLock);
-	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false, false);
 	if(!leaf) return SHAMapItem::pointer();
 	return leaf->findItem(id);
 }
@@ -273,7 +334,7 @@ SHAMapItem::pointer SHAMap::peekItem(const uint256& id)
 bool SHAMap::hasItem(const uint256& id)
 { // does the tree have an item with this ID
 	ScopedLock sl(mLock);  
-	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false, false);
 	if(!leaf) return false;
 	SHAMapItem::pointer item=leaf->findItem(id);
 	return (bool) item;
@@ -282,7 +343,7 @@ bool SHAMap::hasItem(const uint256& id)
 bool SHAMap::delItem(const uint256& id)
 { // delete the item with this ID
 	ScopedLock sl(mLock);
-	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(id, false, false);
 	if(!leaf) return false;
 	if(!leaf->delItem(id)) return false;
 	dirtyUp(id);
@@ -292,7 +353,7 @@ bool SHAMap::delItem(const uint256& id)
 bool SHAMap::addGiveItem(const SHAMapItem::pointer item)
 { // add the specified item
 	ScopedLock sl(mLock);
-	SHAMapLeafNode::pointer leaf=walkToLeaf(item->getTag(), true);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(item->getTag(), true, true);
 	if(!leaf) return false;
 	if(leaf->hasItem(item->getTag())) return false;
 	if(!leaf->addUpdateItem(item)) return false;
@@ -300,10 +361,15 @@ bool SHAMap::addGiveItem(const SHAMapItem::pointer item)
 	return true;
 }

+bool SHAMap::addItem(const SHAMapItem& i)
+{
+	return addGiveItem(SHAMapItem::pointer(new SHAMapItem(i)));
+}
+
 bool SHAMap::updateGiveItem(SHAMapItem::pointer item)
 {
 	ScopedLock sl(mLock);
-	SHAMapLeafNode::pointer leaf=walkToLeaf(item->getTag(), true);
+	SHAMapLeafNode::pointer leaf=walkToLeaf(item->getTag(), true, true);
 	if(!leaf) return false;
 	if(!leaf->addUpdateItem(item)) return false;
 	dirtyUp(item->getTag());
@@ -338,6 +404,14 @@ bool SHAMap::writeLeafNode(const uint256&, const SHAMapNode&, const std::vector<

 void SHAMap::dump()
 {
+	std::cerr << "SHAMap::dump" << std::endl;
+	SHAMapItem::pointer i=peekFirstItem();
+	while(i)
+	{
+		std::cerr << "Item: id=" << i->getTag().GetHex() << std::endl;
+		i=peekNextItem(i->getTag());
+	}
+	std::cerr << "SHAMap::dump done" << std::endl;
 }

 static std::vector<unsigned char>IntToVUC(int i)
@@ -358,6 +432,16 @@ bool SHAMap::TestSHAMap()

 SHAMap sMap;
 SHAMapItem i1(h1, IntToVUC(1)), i2(h2, IntToVUC(2)), i3(h3, IntToVUC(3)), i4(h4, IntToVUC(4)), i5(h5, IntToVUC(5));
+
+#ifdef DEBUG
+ std::cerr << "addItem1" << std::endl;
+#endif
+ sMap.addItem(i1);
+#ifdef DEBUG
+ std::cerr << "addItem2" << std::endl;
+#endif
+ sMap.addItem(i2);
+ sMap.dump();
 
 sMap.dump();
 }
--- a/SHAMap.h
+++ b/SHAMap.h
@@ -17,12 +17,11 @@ class SHAMap;
 // The trees are designed for rapid synchronization and compression of differences


- class SHAMapNode
+class SHAMapNode
 { // Identifies a node in a SHA256 hash
 public:
 	typedef boost::shared_ptr<SHAMapNode> pointer;

-
 private:
 	static uint256 smMasks[11]; // AND with hash to get node id

@@ -56,7 +55,8 @@ public:
 	bool operator<=(const SHAMapNode&) const;
 	bool operator>=(const SHAMapNode&) const;

-	virtual void dump(void);
+	virtual std::string getString(void) const;
+	void dump(void);

 	static void ClassInit();
 	static uint256 getNodeID(int depth, const uint256& hash);
@@ -112,19 +112,27 @@ public:
 private:
 	uint256	mHash;
 	std::list<SHAMapItem::pointer> mItems;
+	uint32 mSeq;

 	bool updateHash();

+	SHAMapLeafNode(const SHAMapLeafNode&); // no implementation
+	SHAMapLeafNode& operator=(const SHAMapLeafNode&); // no implementation
+
 protected:
 	bool addUpdateItem(SHAMapItem::pointer);
 	bool delItem(const SHAMapItem::pointer i) { delItem(i->getTag()); }
 	bool delItem(const uint256& tag);

 public:
-	SHAMapLeafNode(const SHAMapNode& nodeID);
+	SHAMapLeafNode(const SHAMapNode& nodeID, uint32 seq);
+	SHAMapLeafNode(const SHAMapLeafNode& node, uint32 seq);

 	virtual bool isPopulated(void) const { return true; }

+	uint32 getSeq(void) const { return mSeq; }
+	void setSeq(uint32 s) { mSeq=s; }
+
 	const uint256& getNodeHash() const	{ return mHash; }
 	bool isEmpty() const			{ return mItems.empty(); }
 	int getItemCount() const		{ return mItems.size(); }
@@ -150,15 +158,23 @@ public:
 private:
 	uint256		mHash;
 	uint256		mHashes[32];
+	uint32		mSeq;

 	bool updateHash();

+	SHAMapInnerNode(const SHAMapInnerNode&); // no implementation
+	SHAMapInnerNode& operator=(const SHAMapInnerNode&); // no implementation
+
 protected:
 	bool setChildHash(int m, const uint256& hash);

 public:
-	SHAMapInnerNode(const SHAMapNode& id);
-	SHAMapInnerNode(const SHAMapNode& id, const std::vector<unsigned char>& contents);
+	SHAMapInnerNode(const SHAMapNode& id, uint32 seq);
+	SHAMapInnerNode(const SHAMapInnerNode& node, uint32 seq);
+	SHAMapInnerNode(const SHAMapNode& id, const std::vector<unsigned char>& contents, uint32 seq);
+
+	uint32 getSeq(void) const { return mSeq; }
+	void setSeq(uint32 s) { mSeq=s; }

 	virtual bool isPopulated(void) const { return true; }

@@ -183,7 +199,7 @@ public:
 	typedef boost::shared_ptr<SHAMap> pointer;

 private:
-	int mLeafDataSize, mLeafDataOffset, mSeq;
+	uint32 mSeq;
 	mutable boost::recursive_mutex mLock;
 	std::map<SHAMapNode, SHAMapLeafNode::pointer> mLeafByID;
 	std::map<SHAMapNode, SHAMapInnerNode::pointer> mInnerNodeByID;
@@ -197,15 +213,19 @@ protected:

 	SHAMapLeafNode::pointer createLeaf(const SHAMapInnerNode& lowestParent, const uint256& id);
 	SHAMapLeafNode::pointer checkCacheLeaf(const SHAMapNode &);
-	SHAMapLeafNode::pointer walkToLeaf(const uint256& id, bool create);
+	SHAMapLeafNode::pointer walkToLeaf(const uint256& id, bool create, bool modify);

-	SHAMapLeafNode::pointer getLeaf(const SHAMapNode& id, const uint256& hash);
-	SHAMapInnerNode::pointer getInner(const SHAMapNode& id, const uint256& hash);
+	SHAMapLeafNode::pointer getLeaf(const SHAMapNode& id, const uint256& hash, bool modify);
+	SHAMapLeafNode::pointer returnLeaf(SHAMapLeafNode::pointer leaf, bool modify);
+	SHAMapInnerNode::pointer getInner(const SHAMapNode& id, const uint256& hash, bool modify);
+	SHAMapInnerNode::pointer returnNode(SHAMapInnerNode::pointer node, bool modify);

 	SHAMapItem::pointer firstBelow(SHAMapInnerNode::pointer);
 	SHAMapItem::pointer lastBelow(SHAMapInnerNode::pointer);
 	
 public:
+
+	// build new map
 	SHAMap();

 	// hold the map stable across operations
--- a/SHAMapNodes.cpp
+++ b/SHAMapNodes.cpp
@@ -3,6 +3,17 @@
 #include "SHAMap.h"

 #include <boost/foreach.hpp>
+#include <boost/lexical_cast.hpp>
+
+std::string SHAMapNode::getString() const
+{
+	std::string ret="NodeID(";
+	ret+=boost::lexical_cast<std::string>(mDepth);
+	ret+=",";
+	ret+=mNodeID.GetHex();
+	ret+=")";
+	return ret;
+}

 uint256 SHAMapNode::smMasks[11];

@@ -51,7 +62,7 @@ void SHAMapNode::ClassInit()

 	for(i=0; i<64; i++) HexBuf[i]='0';
 		HexBuf[64]=0;
-	for(i=0; i<leafDepth; i++)
+	for(i=0; i<=leafDepth; i++)
 	{
 		smMasks[i].SetHex(HexBuf);
 		HexBuf[2*i]='1';
@@ -98,12 +109,18 @@ int SHAMapNode::selectBranch(const uint256 &hash)

 void SHAMapNode::dump()
 {
-	std::cerr << "MapNode(" << mNodeID.GetHex() << ", " << mDepth << ")" << std::endl;
+	std::cerr << getString() << std::endl;
 }

-SHAMapLeafNode::SHAMapLeafNode(const SHAMapNode& nodeID) : SHAMapNode(nodeID), mHash(0)
+SHAMapLeafNode::SHAMapLeafNode(const SHAMapNode& nodeID, uint32 seq) : SHAMapNode(nodeID), mHash(0), mSeq(seq)
 {
-	assert(nodeID.getDepth()==SHAMapNode::leafDepth);
+	assert(nodeID.isLeaf());
+}
+
+SHAMapLeafNode::SHAMapLeafNode(const SHAMapLeafNode& node, uint32 seq) : SHAMapNode(node),
+		mHash(node.mHash), mItems(node.mItems), mSeq(seq)
+{
+	assert(node.isLeaf());
 }

 bool SHAMapLeafNode::hasItem(const uint256& item) const
@@ -202,17 +219,25 @@ void SHAMapLeafNode::dump()
 	std::cerr << "  " << mItems.size() << " items" << std::endl;
 }

-SHAMapInnerNode::SHAMapInnerNode(const SHAMapNode& id) : SHAMapNode(id)
-{
+SHAMapInnerNode::SHAMapInnerNode(const SHAMapNode& id, uint32 seq) : SHAMapNode(id), mSeq(seq)
+{ // can be root
 	assert(id.getDepth()<SHAMapNode::leafDepth);
 }

-SHAMapInnerNode::SHAMapInnerNode(const SHAMapNode& id, const std::vector<unsigned char>& contents)
-	: SHAMapNode(id)
+SHAMapInnerNode::SHAMapInnerNode(const SHAMapNode& id, const std::vector<unsigned char>& contents, uint32 seq)
+	: SHAMapNode(id), mSeq(seq)
 {
+	assert(!id.isLeaf());
 	Serializer s(contents);
 	for(int i=0; i<32; i++)
-			mHashes[i]=s.get256(i*32);
+		mHashes[i]=s.get256(i*32);
+}
+
+SHAMapInnerNode::SHAMapInnerNode(const SHAMapInnerNode& node, uint32 seq) : SHAMapNode(node), mHash(node.mHash),
+		mSeq(seq)
+{
+	assert(!node.isLeaf());
+	memcpy(mHashes, node.mHashes, sizeof(mHashes));
 }

 bool SHAMapInnerNode::setChildHash(int m, const uint256 &hash)