From b789154c0818127c589a6be7a2f9a34ed2b910a9 Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Thu, 16 Aug 2012 15:59:27 -0700
Subject: [PATCH] SLE support for threading through transactions.

---
 src/LedgerFormats.cpp    |  2 +-
 src/SerializedLedger.cpp | 30 ++++++++++++++++++++++++++++++
 src/SerializedLedger.h   |  6 ++++++
 src/SerializedObject.h   |  3 ++-
 4 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/src/LedgerFormats.cpp b/src/LedgerFormats.cpp
index 5b031ffc99..58507b6d9d 100644
--- a/src/LedgerFormats.cpp
+++ b/src/LedgerFormats.cpp
@@ -10,7 +10,7 @@ LedgerEntryFormat LedgerFormats[]=
 		{ S_FIELD(Sequence),			STI_UINT32,		SOE_REQUIRED, 0 },
 		{ S_FIELD(Balance),				STI_AMOUNT,		SOE_REQUIRED, 0 },
 		{ S_FIELD(LastReceive),			STI_UINT32,		SOE_REQUIRED, 0 },
-		{ S_FIELD(LastTxn),				STI_UINT32,		SOE_REQUIRED, 0 },
+		{ S_FIELD(LastTxnSeq),			STI_UINT32,		SOE_REQUIRED, 0 },
 		{ S_FIELD(AuthorizedKey),		STI_ACCOUNT,	SOE_IFFLAG,   1 },
 		{ S_FIELD(EmailHash),			STI_HASH128,	SOE_IFFLAG,   2 },
 		{ S_FIELD(WalletLocator),		STI_HASH256,	SOE_IFFLAG,   4 },
diff --git a/src/SerializedLedger.cpp b/src/SerializedLedger.cpp
index 372e9cd730..33d42d46c1 100644
--- a/src/SerializedLedger.cpp
+++ b/src/SerializedLedger.cpp
@@ -73,4 +73,34 @@ bool SerializedLedgerEntry::isEquivalent(const SerializedType& t) const
 	if (mObject != v->mObject) return false;
 	return true;
 }
+
+bool SerializedLedgerEntry::isThreadedType()
+{
+	return getIFieldIndex(sfLastTxnID) != -1;
+}
+
+bool SerializedLedgerEntry::isThreaded()
+{
+	return getIFieldPresent(sfLastTxnID);
+}
+
+uint256 SerializedLedgerEntry::getThreadedTransaction()
+{
+	return getIFieldH256(sfLastTxnID);
+}
+
+uint32 SerializedLedgerEntry::getThreadedLedger()
+{
+	return getIFieldU32(sfLastTxnSeq);
+}
+
+void SerializedLedgerEntry::thread(const uint256& txID, uint32 ledgerSeq, uint256& prevTxID, uint32& prevLedgerID)
+{
+	prevTxID = getIFieldH256(sfLastTxnID);
+	prevLedgerID = getIFieldU32(sfLastTxnID);
+	assert(prevTxID != txID);
+	setIFieldH256(sfLastTxnID, txID);
+	setIFieldU32(sfLastTxnSeq, ledgerSeq);
+}
+
 // vim:ts=4
diff --git a/src/SerializedLedger.h b/src/SerializedLedger.h
index 6df79d7e88..c629ddbbce 100644
--- a/src/SerializedLedger.h
+++ b/src/SerializedLedger.h
@@ -62,6 +62,12 @@ public:
 	STAmount getIValueFieldAmount(SOE_Field field) const { return mObject.getValueFieldAmount(field); }
 	STVector256 getIFieldV256(SOE_Field field) { return mObject.getValueFieldV256(field); }
 
+	bool isThreadedType();	// is this a ledger entry that can be threaded
+	bool isThreaded();		// is this ledger entry actually threaded
+	uint256 getThreadedTransaction();
+	uint32 getThreadedLedger();
+	void thread(const uint256& txID, uint32 ledgerSeq, uint256& prevTxID, uint32& prevLedgerID);
+
 	void setIFieldU8(SOE_Field field, unsigned char v) { return mObject.setValueFieldU8(field, v); }
 	void setIFieldU16(SOE_Field field, uint16 v) { return mObject.setValueFieldU16(field, v); }
 	void setIFieldU32(SOE_Field field, uint32 v) { return mObject.setValueFieldU32(field, v); }
diff --git a/src/SerializedObject.h b/src/SerializedObject.h
index 0480266bee..e8df6729f4 100644
--- a/src/SerializedObject.h
+++ b/src/SerializedObject.h
@@ -64,7 +64,8 @@ enum SOE_Field
 	sfInvoiceID,
 	sfLastNode,
 	sfLastReceive,
-	sfLastTxn,
+	sfLastTxnID,
+	sfLastTxnSeq,
 	sfLedgerHash,
 	sfLimitAmount,
 	sfLowID,