From 00913f838fb6e6cf9b9d8716333192bb993946c0 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Sun, 17 Mar 2013 22:04:34 -0700
Subject: [PATCH] Fix the 'getAccountHash() == mAccountStateMap->getHash()'
 bug. 'getNeededHashes' can do the wrong thing (report no needed hashes when
 we need them all) if we have a ledger's root node but not the root node of
 the tree we're querying.

---
 src/cpp/ripple/Ledger.cpp        | 26 ++++++++++++++++++++++++++
 src/cpp/ripple/Ledger.h          |  3 +++
 src/cpp/ripple/LedgerAcquire.cpp | 11 +++++++----
 3 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/src/cpp/ripple/Ledger.cpp b/src/cpp/ripple/Ledger.cpp
index ddb4bc441..d9fdab4ca 100644
--- a/src/cpp/ripple/Ledger.cpp
+++ b/src/cpp/ripple/Ledger.cpp
@@ -1614,6 +1614,32 @@ uint64 Ledger::scaleFeeLoad(uint64 fee)
 	return theApp->getFeeTrack().scaleFeeLoad(fee, mBaseFee, mReferenceFeeUnits);
 }
 
+std::vector<uint256> Ledger::getNeededTransactionHashes(int max)
+{
+	std::vector<uint256> ret;
+	if (mTransHash.isNonZero())
+	{
+		if (mTransactionMap->getHash().isZero())
+			ret.push_back(mTransHash);
+		else
+			ret = mTransactionMap->getNeededHashes(max);
+	}
+	return ret;
+}
+
+std::vector<uint256> Ledger::getNeededAccountStateHashes(int max)
+{
+	std::vector<uint256> ret;
+	if (mAccountHash.isNonZero())
+	{
+		if (mAccountStateMap->getHash().isZero())
+			ret.push_back(mAccountHash);
+		else
+			ret = mAccountStateMap->getNeededHashes(max);
+	}
+	return ret;
+}
+
 BOOST_AUTO_TEST_SUITE(quality)
 
 BOOST_AUTO_TEST_CASE( getquality )
diff --git a/src/cpp/ripple/Ledger.h b/src/cpp/ripple/Ledger.h
index c260a0443..5dda84880 100644
--- a/src/cpp/ripple/Ledger.h
+++ b/src/cpp/ripple/Ledger.h
@@ -222,6 +222,9 @@ public:
 	static uint256 getLedgerFeatureIndex();
 	static uint256 getLedgerFeeIndex();
 
+	std::vector<uint256> getNeededTransactionHashes(int max);
+	std::vector<uint256> getNeededAccountStateHashes(int max);
+
 	// index calculation functions
 	static uint256 getAccountRootIndex(const uint160& uAccountID);
 
diff --git a/src/cpp/ripple/LedgerAcquire.cpp b/src/cpp/ripple/LedgerAcquire.cpp
index 9e9e307e7..e345dc18c 100644
--- a/src/cpp/ripple/LedgerAcquire.cpp
+++ b/src/cpp/ripple/LedgerAcquire.cpp
@@ -139,7 +139,7 @@ bool LedgerAcquire::tryLocal()
 			{
 				mLedger->peekTransactionMap()->fetchRoot(mLedger->getTransHash());
 				cLog(lsDEBUG) << "Got root txn map locally";
-				std::vector<uint256> h = mLedger->peekTransactionMap()->getNeededHashes(1);
+				std::vector<uint256> h = mLedger->getNeededTransactionHashes(1);
 				if (h.empty())
 				{
 					cLog(lsDEBUG) << "Had full txn map locally";
@@ -155,14 +155,17 @@ bool LedgerAcquire::tryLocal()
 	if (!mHaveState)
 	{
 		if (mLedger->getAccountHash().isZero())
+		{
+			cLog(lsFATAL) << "We are acquiring a ledger with a zero account hash";
 			mHaveState = true;
+		}
 		else
 		{
 			try
 			{
 				mLedger->peekAccountStateMap()->fetchRoot(mLedger->getAccountHash());
 				cLog(lsDEBUG) << "Got root AS map locally";
-				std::vector<uint256> h = mLedger->peekAccountStateMap()->getNeededHashes(1);
+				std::vector<uint256> h = mLedger->getNeededAccountStateHashes(1);
 				if (h.empty())
 				{
 					cLog(lsDEBUG) << "Had full AS map locally";
@@ -783,13 +786,13 @@ std::vector<LedgerAcquire::neededHash_t> LedgerAcquire::getNeededHashes()
 	}
 	if (!mHaveState)
 	{
-		std::vector<uint256> v = mLedger->peekAccountStateMap()->getNeededHashes(16);
+		std::vector<uint256> v = mLedger->getNeededAccountStateHashes(16);
 		BOOST_FOREACH(const uint256& h, v)
 			ret.push_back(std::make_pair(ripple::TMGetObjectByHash::otSTATE_NODE, h));
 	}
 	if (!mHaveTransactions)
 	{
-		std::vector<uint256> v = mLedger->peekTransactionMap()->getNeededHashes(16);
+		std::vector<uint256> v = mLedger->getNeededAccountStateHashes(16);
 		BOOST_FOREACH(const uint256& h, v)
 			ret.push_back(std::make_pair(ripple::TMGetObjectByHash::otTRANSACTION_NODE, h));
 	}