From 30dd46d8124bffdf2219919f5db8d4cf8e2b909d Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Thu, 11 Oct 2012 02:50:04 -0700
Subject: [PATCH] Improve SHAMapMissingNode

---
 src/SHAMap.cpp     | 18 ++++++++++++------
 src/SHAMap.h       | 14 ++++++++++++--
 src/SHAMapSync.cpp |  7 ++++---
 3 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/src/SHAMap.cpp b/src/SHAMap.cpp
index 5dd31f5651..533b9d6710 100644
--- a/src/SHAMap.cpp
+++ b/src/SHAMap.cpp
@@ -93,7 +93,8 @@ std::stack<SHAMapTreeNode::pointer> SHAMap::getStack(const uint256& id, bool inc
 		{
 			if (partialOk)
 				return stack;
-			throw mn;
+			mn.setTargetNode(id);
+			throw;
 		}
 	}
 
@@ -153,10 +154,15 @@ SHAMapTreeNode::pointer SHAMap::walkTo(const uint256& id, bool modify)
 			return inNode;
 		uint256 childHash = inNode->getChildHash(branch);
 
-		SHAMapTreeNode::pointer nextNode = getNode(inNode->getChildNodeID(branch), childHash, false);
-		if (!nextNode)
-			throw SHAMapMissingNode(inNode->getChildNodeID(branch), childHash);
-		inNode = nextNode;
+		try
+		{
+			inNode = getNode(inNode->getChildNodeID(branch), childHash, false);
+		}
+		catch (SHAMapMissingNode& mn)
+		{
+			mn.setTargetNode(id);
+			throw;
+		}
 	}
 	if (inNode->getTag() != id)
 		return SHAMapTreeNode::pointer();
@@ -175,7 +181,7 @@ SHAMapTreeNode* SHAMap::walkToPointer(const uint256& id)
 		if (nextHash.isZero()) return NULL;
 		inNode = getNodePointer(inNode->getChildNodeID(branch), nextHash);
 		if (!inNode)
-			throw SHAMapMissingNode(inNode->getChildNodeID(branch), nextHash);
+			throw SHAMapMissingNode(inNode->getChildNodeID(branch), nextHash, id);
 	}
 	return (inNode->getTag() == id) ? inNode : NULL;
 }
diff --git a/src/SHAMap.h b/src/SHAMap.h
index c239bad307..a942943b1a 100644
--- a/src/SHAMap.h
+++ b/src/SHAMap.h
@@ -241,16 +241,26 @@ class SHAMapMissingNode : public std::runtime_error
 protected:
 	SHAMapNode mNodeID;
 	uint256 mNodeHash;
+	uint256 mTargetIndex;
 
 public:
 	SHAMapMissingNode(const SHAMapNode& nodeID, const uint256& nodeHash) :
 		std::runtime_error(nodeID.getString()), mNodeID(nodeID), mNodeHash(nodeHash)
 	{ ; }
+
+	SHAMapMissingNode(const SHAMapNode& nodeID, const uint256& nodeHash, const uint256& targetIndex) :
+		std::runtime_error(nodeID.getString()), mNodeID(nodeID), mNodeHash(nodeHash), mTargetIndex(targetIndex)
+	{ ; }
+
 	virtual ~SHAMapMissingNode() throw()
 	{ ; }
 
-	const SHAMapNode& getNodeID() const	{ return mNodeID; }
-	const uint256& getNodeHash() const	{ return mNodeHash; }
+	void setTargetNode(const uint256& tn)	{ mTargetIndex = tn; }
+
+	const SHAMapNode& getNodeID() const		{ return mNodeID; }
+	const uint256& getNodeHash() const		{ return mNodeHash; }
+	const uint256& getTargetIndex() const	{ return mTargetIndex; }
+	bool hasTargetIndex() const				{ return !mTargetIndex.isZero(); }
 };
 
 class SHAMap
diff --git a/src/SHAMapSync.cpp b/src/SHAMapSync.cpp
index fef3cf04ad..baf7de9501 100644
--- a/src/SHAMapSync.cpp
+++ b/src/SHAMapSync.cpp
@@ -53,7 +53,7 @@ void SHAMap::getMissingNodes(std::vector<SHAMapNode>& nodeIDs, std::vector<uint2
 				{
 					d = getNode(childID, childHash, false);
 				}
-				catch (SHAMapMissingNode& )
+				catch (SHAMapMissingNode&)
 				{ // node is not in the map
 					if (filter != NULL)
 					{
@@ -269,14 +269,15 @@ bool SHAMap::addKnownNode(const SHAMapNode& node, const std::vector<unsigned cha
 					if (nextNode->isInner() && !nextNode->isFullBelow())
 						return true;
 				}
-				catch (SHAMapMissingNode)
+				catch (SHAMapMissingNode&)
 				{
 					return true;
 				}
 			}
 		iNode->setFullBelow();
 	} while (!stack.empty());
-	if (root->isFullBelow()) clearSynching();
+	if (root->isFullBelow())
+		clearSynching();
 	return true;
 }