Clean up old acquires.

src/cpp/ripple/Application.cpp

@@ -275,6 +275,7 @@ void Application::sweep()
 	mLedgerMaster.sweep();
 	mTempNodeCache.sweep();
 	mValidations.sweep();
+	getMasterLedgerAcquire().sweep();
 	mSweepTimer.expires_from_now(boost::posix_time::seconds(60));
 	mSweepTimer.async_wait(boost::bind(&Application::sweep, this));
 }

src/cpp/ripple/LedgerAcquire.cpp

@@ -724,4 +724,18 @@ bool LedgerAcquireMaster::isFailure(const uint256& hash)
 	return mRecentFailures.find(hash) != mRecentFailures.end();
 }
 
+void LedgerAcquireMaster::sweep()
+{
+	boost::mutex::scoped_lock sl(mLock);
+
+	std::map<uint256, LedgerAcquire::pointer>::iterator it = mLedgers.begin();
+	while (it != mLedgers.end())
+	{
+		if (it->second->isDone())
+			mLedgers.erase(it++);
+		else
+			++it;
+	}
+}
+
 // vim:ts=4

src/cpp/ripple/LedgerAcquire.h

@@ -133,6 +133,8 @@ public:
 
 	void logFailure(const uint256&);
 	bool isFailure(const uint256&);
+
+	void sweep();
 };
 
 #endif