From 50fe4b63209202a17e54163b8201561cbd7b2bd6 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Mon, 9 Jul 2012 16:06:15 -0700
Subject: [PATCH] Functions that return an SLE::pointer that find the next/prev
 nodes in the state tree.

---
 src/Ledger.h       |  6 ++++++
 src/LedgerNode.cpp | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/src/Ledger.h b/src/Ledger.h
index fe0d1ab157..d5565f622c 100644
--- a/src/Ledger.h
+++ b/src/Ledger.h
@@ -152,6 +152,12 @@ public:
 	static Ledger::pointer loadByIndex(uint32 ledgerIndex);
 	static Ledger::pointer loadByHash(const uint256& ledgerHash);
 
+	// next/prev function
+	SLE::pointer getNextSLE(const uint256& hash);						// first node >hash
+	SLE::pointer getNextSLE(const uint256& hash, const uint256& max); 	// first node >hash, <max
+	SLE::pointer getPrevSLE(const uint256& hash);						// last node <hash
+	SLE::pointer getPrevSLE(const uint256& hash, const uint256& min);	// last node <hash, >min
+
 	// index calculation functions
 	static uint256 getAccountRootIndex(const uint160& uAccountID);
 
diff --git a/src/LedgerNode.cpp b/src/LedgerNode.cpp
index c600c8f367..2013247ad1 100644
--- a/src/LedgerNode.cpp
+++ b/src/LedgerNode.cpp
@@ -43,6 +43,38 @@ LedgerStateParms Ledger::writeBack(LedgerStateParms parms, SLE::pointer entry)
 	return lepOKAY;
 }
 
+SLE::pointer Ledger::getNextSLE(const uint256& hash)
+{
+	SHAMapItem::pointer node = mAccountStateMap->peekNextItem(hash);
+	if (!node)
+		return SLE::pointer();
+	return boost::make_shared<SLE>(node->peekSerializer(), node->getTag());
+}
+
+SLE::pointer Ledger::getNextSLE(const uint256& hash, const uint256& max)
+{
+	SHAMapItem::pointer node = mAccountStateMap->peekNextItem(hash);
+	if ((!node) || (node->getTag() > max))
+		return SLE::pointer();
+	return boost::make_shared<SLE>(node->peekSerializer(), node->getTag());
+}
+
+SLE::pointer Ledger::getPrevSLE(const uint256& hash)
+{
+	SHAMapItem::pointer node = mAccountStateMap->peekPrevItem(hash);
+	if (!node)
+		return SLE::pointer();
+	return boost::make_shared<SLE>(node->peekSerializer(), node->getTag());
+}
+
+SLE::pointer Ledger::getPrevSLE(const uint256& hash, const uint256& min)
+{
+	SHAMapItem::pointer node = mAccountStateMap->peekNextItem(hash);
+	if ((!node) || (node->getTag() < min))
+		return SLE::pointer();
+	return boost::make_shared<SLE>(node->peekSerializer(), node->getTag());
+}
+
 SLE::pointer Ledger::getASNode(LedgerStateParms& parms, const uint256& nodeID,
  LedgerEntryType let )
 {