From e8e927a0fb774d1e974eff339694f82e32a71e2a Mon Sep 17 00:00:00 2001
From: JoelKatz <DavidJoelSchwartz@GMail.com>
Date: Fri, 29 Mar 2013 16:45:31 -0700
Subject: [PATCH] Last path must provide adequate liquidity.

---
 src/cpp/ripple/Pathfinder.cpp | 30 ++++++++++--------------------
 1 file changed, 10 insertions(+), 20 deletions(-)

diff --git a/src/cpp/ripple/Pathfinder.cpp b/src/cpp/ripple/Pathfinder.cpp
index fe2e9c9ade..78280190cb 100644
--- a/src/cpp/ripple/Pathfinder.cpp
+++ b/src/cpp/ripple/Pathfinder.cpp
@@ -79,7 +79,7 @@ PathOption::PathOption(PathOption::pointer other)
 #endif
 
 // quality, length, liquidity, index
-typedef boost::tuple<uint64, int, STAmount, bool, unsigned int> path_LQ_t;
+typedef boost::tuple<uint64, int, STAmount, unsigned int> path_LQ_t;
 
 // Lower numbers have better quality. Sort higher quality first.
 static bool bQualityCmp(const path_LQ_t& a, const path_LQ_t&b)
@@ -587,7 +587,7 @@ bool Pathfinder::findPaths(const unsigned int iMaxSteps, const unsigned int iMax
 						% uQuality
 						% spCurrent.getJson(0));
 
-				vMap.push_back(path_LQ_t(uQuality, spCurrent.mPath.size(), saDstAmountAct, false, i));
+				vMap.push_back(path_LQ_t(uQuality, spCurrent.mPath.size(), saDstAmountAct, i));
 			}
 			else
 			{
@@ -600,35 +600,25 @@ bool Pathfinder::findPaths(const unsigned int iMaxSteps, const unsigned int iMax
 
 		if (vMap.size())
 		{
-			iLimit	= std::min(iMaxPaths, (unsigned int) vMap.size());
-
 			bFound	= true;
 
 			std::sort(vMap.begin(), vMap.end(), bQualityCmp);	// Lower is better and should be first.
 
 			// Output best quality entries.
 			STAmount remaining = mDstAmount;
-			for (int i = 0; i < iLimit; ++i)
+			for (int i = 0, iPathsLeft = iMaxPaths; (iPathsLeft > 0) && (i < vMap.size()); ++i)
 			{
 				path_LQ_t& lqt = vMap[i];
-				remaining -= lqt.get<2>();
-				lqt.get<3>() = true;
-				spsDst.addPath(vspResults[lqt.get<4>()]);
-			}
-
-			if (remaining.isGEZero())
-			{ // we need an extra path to ensure liquidity
-				for (int i = 0; i < vMap.size(); ++i)
-				{
-					path_LQ_t& lqt = vMap[i];
-					if (!lqt.get<3>() && (lqt.get<2>() >= remaining))
-					{
-						spsDst.addPath(vspResults[lqt.get<4>()]);
-						break;
-					}
+				if ((iPathsLeft != 1) || (lqt.get<2>() >= remaining))
+				{ // last path must fill
+					--iPathsLeft;
+					remaining -= lqt.get<2>();
+					spsDst.addPath(vspResults[lqt.get<3>()]);
 				}
 			}
 
+			bFound = !remaining.isGEZero();
+
 			cLog(lsDEBUG) << boost::str(boost::format("findPaths: RESULTS: %s") % spsDst.getJson(0));
 		}
 		else