Merge

12 files changed, 598 insertions, 710 deletions

diff --git a/indra/llmessage/llinstantmessage.cpp b/indra/llmessage/llinstantmessage.cpp
index b7f3e6e4f7..dd5a655d7e 100644
--- a/indra/llmessage/llinstantmessage.cpp
+++ b/indra/llmessage/llinstantmessage.cpp
@@ -51,98 +51,6 @@ const std::string INTERACTIVE_SYSTEM_FROM("F387446C-37C4-45f2-A438-D99CBDBB563B"
 const S32 IM_TTL = 1;
 
 
-/**
- * LLIMInfo
- */
-LLIMInfo::LLIMInfo() :
-	mFromGroup(FALSE),
-	mParentEstateID(0),
-	mOffline(0),
-	mViewerThinksToIsOnline(false),
-	mIMType(IM_NOTHING_SPECIAL),
-	mTimeStamp(0),
-	mTTL(IM_TTL)
-{
-}
-
-LLIMInfo::LLIMInfo(
-	const LLUUID& from_id,
-	BOOL from_group,
-	const LLUUID& to_id,
-	EInstantMessage im_type, 
-	const std::string& name,
-	const std::string& message,
-	const LLUUID& id,
-	U32 parent_estate_id,
-	const LLUUID& region_id,
-	const LLVector3& position,
-	LLSD data,
-	U8 offline,
-	U32 timestamp,
-	S32 ttl) :
-	mFromID(from_id),
-	mFromGroup(from_group),
-	mToID(to_id),
-	mParentEstateID(0),
-	mRegionID(region_id),
-	mPosition(position),
-	mOffline(offline),
-	mViewerThinksToIsOnline(false),
-	mIMType(im_type),
-	mID(id),
-	mTimeStamp(timestamp),
-	mName(name),
-	mMessage(message),
-	mData(data),
-	mTTL(ttl)
-{
-}
-
-LLIMInfo::LLIMInfo(LLMessageSystem* msg, S32 ttl) :
-	mViewerThinksToIsOnline(false),
-	mTTL(ttl)
-{
-	unpackMessageBlock(msg);
-}
-
-LLIMInfo::~LLIMInfo()
-{
-}
-
-void LLIMInfo::packInstantMessage(LLMessageSystem* msg) const
-{
-	LL_DEBUGS() << "LLIMInfo::packInstantMessage()" << LL_ENDL;
-	msg->newMessageFast(_PREHASH_ImprovedInstantMessage);
-	packMessageBlock(msg);
-}
-
-void LLIMInfo::packMessageBlock(LLMessageSystem* msg) const
-{
-	// Construct binary bucket
-	std::vector<U8> bucket;
-	if (mData.has("binary_bucket"))
-	{
-		bucket = mData["binary_bucket"].asBinary();
-	}
-	pack_instant_message_block(
-		msg,
-		mFromID,
-		mFromGroup,
-		LLUUID::null,
-		mToID,
-		mName,
-		mMessage,
-		mOffline,
-		mIMType,
-		mID,
-		mParentEstateID,
-		mRegionID,
-		mPosition,
-		mTimeStamp,
-		&bucket[0],
-		bucket.size());
-}
-
 void pack_instant_message(
 	LLMessageSystem* msg,
 	const LLUUID& from_id,
@@ -253,120 +161,4 @@ void pack_instant_message_block(
 	msg->addBinaryDataFast(_PREHASH_BinaryBucket, bb, binary_bucket_size);
 }
 
-void LLIMInfo::unpackMessageBlock(LLMessageSystem* msg)
-{
-	msg->getUUIDFast(_PREHASH_AgentData, _PREHASH_AgentID, mFromID);
-	msg->getBOOLFast(_PREHASH_MessageBlock, _PREHASH_FromGroup, mFromGroup);
-	msg->getUUIDFast(_PREHASH_MessageBlock, _PREHASH_ToAgentID, mToID);
-	msg->getU32Fast(_PREHASH_MessageBlock, _PREHASH_ParentEstateID, mParentEstateID);
-	msg->getUUIDFast(_PREHASH_MessageBlock, _PREHASH_RegionID, mRegionID);
-	msg->getVector3Fast(_PREHASH_MessageBlock, _PREHASH_Position, mPosition);
-	msg->getU8Fast(_PREHASH_MessageBlock, _PREHASH_Offline, mOffline);
-	U8 dialog;
-	msg->getU8Fast(_PREHASH_MessageBlock, _PREHASH_Dialog, dialog);
-	mIMType = (EInstantMessage) dialog;
-	msg->getUUIDFast(_PREHASH_MessageBlock, _PREHASH_ID, mID);
-	msg->getU32Fast(_PREHASH_MessageBlock, _PREHASH_Timestamp, mTimeStamp);
-	msg->getStringFast(_PREHASH_MessageBlock, _PREHASH_FromAgentName, mName);
-
-	msg->getStringFast(_PREHASH_MessageBlock, _PREHASH_Message, mMessage);
-
-	S32 binary_bucket_size = llmin(
-		MTUBYTES,
-		msg->getSizeFast(
-			_PREHASH_MessageBlock,
-			_PREHASH_BinaryBucket));
-	if(binary_bucket_size > 0)
-	{
-		std::vector<U8> bucket;
-		bucket.resize(binary_bucket_size);
-
-		msg->getBinaryDataFast(
-			_PREHASH_MessageBlock,
-			_PREHASH_BinaryBucket,
-			&bucket[0],
-			0,
-			0,
-			binary_bucket_size);
-		mData["binary_bucket"] = bucket;
-	}
-	else
-	{
-		mData.clear();
-	}
-}
-
-LLSD im_info_to_llsd(LLPointer<LLIMInfo> im_info)
-{
-	LLSD param_version;
-	param_version["version"] = 1;
-	LLSD param_message;
-	param_message["from_id"] = im_info->mFromID;
-	param_message["from_group"] = im_info->mFromGroup;
-	param_message["to_id"] = im_info->mToID;
-	param_message["from_name"] = im_info->mName;
-	param_message["message"] = im_info->mMessage;
-	param_message["type"] = (S32)im_info->mIMType;
-	param_message["id"] = im_info->mID;
-	param_message["timestamp"] = (S32)im_info->mTimeStamp;
-	param_message["offline"] = (S32)im_info->mOffline;
-	param_message["parent_estate_id"] = (S32)im_info->mParentEstateID;
-	param_message["region_id"] = im_info->mRegionID;
-	param_message["position"] = ll_sd_from_vector3(im_info->mPosition);
-	param_message["data"] = im_info->mData;
-	param_message["ttl"] = im_info->mTTL;
-
-	LLSD param_agent;
-	param_agent["agent_id"] = im_info->mFromID;
-
-	LLSD params;
-	params["version_params"] = param_version;
-	params["message_params"] = param_message;
-	params["agent_params"] = param_agent;
-
-	return params;
-}
-
-LLPointer<LLIMInfo> llsd_to_im_info(const LLSD& im_info_sd)
-{
-	LLSD param_message = im_info_sd["message_params"];
-	LLSD param_agent = im_info_sd["agent_params"];
-
-	LLPointer<LLIMInfo> im_info = new LLIMInfo(
-		param_message["from_id"].asUUID(),
-		param_message["from_group"].asBoolean(),
-		param_message["to_id"].asUUID(),
-		(EInstantMessage) param_message["type"].asInteger(),
-		param_message["from_name"].asString(),
-		param_message["message"].asString(),
-		param_message["id"].asUUID(),
-		(U32) param_message["parent_estate_id"].asInteger(),
-		param_message["region_id"].asUUID(),
-		ll_vector3_from_sd(param_message["position"]),
-		param_message["data"],
-		(U8) param_message["offline"].asInteger(),
-		(U32) param_message["timestamp"].asInteger(),
-		param_message["ttl"].asInteger());
-
-	return im_info;
-}
-
-LLPointer<LLIMInfo> LLIMInfo::clone()
-{
-	return new LLIMInfo(
-			mFromID,
-			mFromGroup,
-			mToID,
-			mIMType,
-			mName,
-			mMessage,
-			mID,
-			mParentEstateID,
-			mRegionID,
-			mPosition,
-			mData,
-			mOffline,
-			mTimeStamp,
-			mTTL);
-}
 
diff --git a/indra/llmessage/llinstantmessage.h b/indra/llmessage/llinstantmessage.h
index f7118f8ccf..55cda15405 100644
--- a/indra/llmessage/llinstantmessage.h
+++ b/indra/llmessage/llinstantmessage.h
@@ -177,59 +177,6 @@ extern const std::string INTERACTIVE_SYSTEM_FROM;
 // Number of retry attempts on sending the im.
 extern const S32 IM_TTL;
 
-
-class LLIMInfo : public LLRefCount
-{
-protected:
-	LLIMInfo();
-	~LLIMInfo();
-
-public:
-	LLIMInfo(LLMessageSystem* msg, 
-			S32 ttl = IM_TTL);
-
-	LLIMInfo(
-		const LLUUID& from_id,
-		BOOL from_group,
-		const LLUUID& to_id,
-		EInstantMessage im_type, 
-		const std::string& name,
-		const std::string& message,
-		const LLUUID& id,
-		U32 parent_estate_id,
-		const LLUUID& region_id,
-		const LLVector3& position,
-		LLSD data,
-		U8 offline,
-		U32 timestamp,
-		S32 ttl = IM_TTL);
-
-	void packInstantMessage(LLMessageSystem* msg) const;
-	void packMessageBlock(LLMessageSystem* msg) const;
-	void unpackMessageBlock(LLMessageSystem* msg);
-	LLPointer<LLIMInfo> clone();
-public:
-	LLUUID mFromID;
-	BOOL mFromGroup;
-	LLUUID mToID;
-	U32 mParentEstateID;
-	LLUUID mRegionID;
-	LLVector3 mPosition;
-	U8 mOffline;
-	bool mViewerThinksToIsOnline;
-	EInstantMessage mIMType; 
-	LLUUID mID;
-	U32 mTimeStamp;
-	std::string mName;
-	std::string mMessage;
-	LLSD mData;
-
-	S32 mTTL;
-};
-
-LLPointer<LLIMInfo> llsd_to_im_info(const LLSD& im_info_sd);
-LLSD im_info_to_llsd(LLPointer<LLIMInfo> im_info);
-
 void pack_instant_message(
 	LLMessageSystem* msgsystem,
 	const LLUUID& from_id,
diff --git a/indra/llmessage/llxfer.cpp b/indra/llmessage/llxfer.cpp
index e0590dfdff..c8b9d5d19f 100644
--- a/indra/llmessage/llxfer.cpp
+++ b/indra/llmessage/llxfer.cpp
@@ -63,7 +63,6 @@ void LLXfer::init (S32 chunk_size)
 	mXferSize = 0;
 
 	mStatus = e_LL_XFER_UNINITIALIZED;
-	mNext = NULL;
 	mWaitingForACK = FALSE;
 	
 	mCallback = NULL;
@@ -99,7 +98,22 @@ void LLXfer::cleanup ()
 
 S32 LLXfer::startSend (U64 xfer_id, const LLHost &remote_host)
 {
-	LL_WARNS() << "undifferentiated LLXfer::startSend for " << getFileName() << LL_ENDL;
+	LL_WARNS("Xfer") << "unexpected call to base class LLXfer::startSend for " << getFileName() << LL_ENDL;
+	return (-1);
+}
+
+///////////////////////////////////////////////////////////
+
+void LLXfer::closeFileHandle()
+{
+	LL_WARNS("Xfer") << "unexpected call to base class LLXfer::closeFileHandle for " << getFileName() << LL_ENDL;
+}
+
+///////////////////////////////////////////////////////////
+
+S32 LLXfer::reopenFileHandle()
+{
+	LL_WARNS("Xfer") << "unexpected call to base class LLXfer::reopenFileHandle for " << getFileName() << LL_ENDL;
 	return (-1);
 }
 
@@ -115,7 +129,7 @@ void LLXfer::setXferSize (S32 xfer_size)
 
 S32 LLXfer::startDownload()
 {
-	LL_WARNS() << "undifferentiated LLXfer::startDownload for " << getFileName()
+	LL_WARNS("Xfer") << "undifferentiated LLXfer::startDownload for " << getFileName()
 			<< LL_ENDL;
 	return (-1);
 }
@@ -127,20 +141,20 @@ S32 LLXfer::receiveData (char *datap, S32 data_size)
 	S32 retval = 0;
 
 	if (((S32) mBufferLength + data_size) > getMaxBufferSize())
-	{
+	{	// Write existing data to disk if it's larger than the buffer size
 		retval = flush();
 	}
 
 	if (!retval)
 	{
 		if (datap != NULL)
-		{
+		{	// Append new data to mBuffer
 			memcpy(&mBuffer[mBufferLength],datap,data_size);	/*Flawfinder: ignore*/
 			mBufferLength += data_size;
 		}
 		else
 		{
-			LL_ERRS() << "NULL data passed in receiveData" << LL_ENDL;
+			LL_ERRS("Xfer") << "NULL data passed in receiveData" << LL_ENDL;
 		}
 	}
 
@@ -163,7 +177,7 @@ S32 LLXfer::flush()
 
 S32 LLXfer::suck(S32 start_position)
 {
-	LL_WARNS() << "Attempted to send a packet outside the buffer bounds in LLXfer::suck()" << LL_ENDL;
+	LL_WARNS("Xfer") << "Attempted to send a packet outside the buffer bounds in LLXfer::suck()" << LL_ENDL;
 	return (-1);
 }
 
@@ -196,7 +210,7 @@ void LLXfer::sendPacket(S32 packet_num)
 
 	if (fdata_size < 0)
 	{
-		LL_WARNS() << "negative data size in xfer send, aborting" << LL_ENDL;
+		LL_WARNS("Xfer") << "negative data size in xfer send, aborting" << LL_ENDL;
 		abort(LL_ERR_EOF);
 		return;
 	}
@@ -248,7 +262,12 @@ void LLXfer::sendPacket(S32 packet_num)
 		gMessageSystem->nextBlockFast(_PREHASH_DataPacket);
 		gMessageSystem->addBinaryDataFast(_PREHASH_Data, &fdata_buf,fdata_size);
 			
-		gMessageSystem->sendMessage(mRemoteHost);
+		S32 sent_something = gMessageSystem->sendMessage(mRemoteHost);
+		if (sent_something == 0)
+		{
+			abort(LL_ERR_CIRCUIT_GONE);
+			return;
+		}
 
 		ACKTimer.reset();
 		mWaitingForACK = TRUE;
@@ -289,12 +308,12 @@ S32 LLXfer::processEOF()
 
 	if (LL_ERR_NOERR == mCallbackResult)
 	{
-		LL_INFOS() << "xfer from " << mRemoteHost << " complete: " << getFileName()
+		LL_INFOS("Xfer") << "xfer from " << mRemoteHost << " complete: " << getFileName()
 				<< LL_ENDL;
 	}
 	else
 	{
-		LL_INFOS() << "xfer from " << mRemoteHost << " failed or aborted, code "
+		LL_INFOS("Xfer") << "xfer from " << mRemoteHost << " failed, code "
 				<< mCallbackResult << ": " << getFileName() << LL_ENDL;
 	}
 
@@ -323,15 +342,18 @@ void LLXfer::abort (S32 result_code)
 {
 	mCallbackResult = result_code;
 
-	LL_INFOS() << "Aborting xfer from " << mRemoteHost << " named " << getFileName()
+	LL_INFOS("Xfer") << "Aborting xfer from " << mRemoteHost << " named " << getFileName()
 			<< " - error: " << result_code << LL_ENDL;
 
-	gMessageSystem->newMessageFast(_PREHASH_AbortXfer);
-	gMessageSystem->nextBlockFast(_PREHASH_XferID);
-	gMessageSystem->addU64Fast(_PREHASH_ID, mID);
-	gMessageSystem->addS32Fast(_PREHASH_Result, result_code);
-	
-	gMessageSystem->sendMessage(mRemoteHost);
+	if (result_code != LL_ERR_CIRCUIT_GONE)
+	{
+		gMessageSystem->newMessageFast(_PREHASH_AbortXfer);
+		gMessageSystem->nextBlockFast(_PREHASH_XferID);
+		gMessageSystem->addU64Fast(_PREHASH_ID, mID);
+		gMessageSystem->addS32Fast(_PREHASH_Result, result_code);
+
+		gMessageSystem->sendMessage(mRemoteHost);
+	}
 
 	mStatus = e_LL_XFER_ABORTED;
 }
diff --git a/indra/llmessage/llxfer.h b/indra/llmessage/llxfer.h
index edf5eeb82d..a906674dec 100644
--- a/indra/llmessage/llxfer.h
+++ b/indra/llmessage/llxfer.h
@@ -54,7 +54,6 @@ class LLXfer
         S32 mChunkSize;
   
  public:
-	LLXfer *mNext;
 	U64 mID;
 	S32 mPacketNum;
 
@@ -62,7 +61,7 @@ class LLXfer
 	S32 mXferSize;
 
 	char *mBuffer;
-	U32 mBufferLength;
+	U32 mBufferLength;			// Size of valid data, not actual allocated buffer size
 	U32 mBufferStartOffset;
 	BOOL mBufferContainsEOF;
 
@@ -90,7 +89,9 @@ class LLXfer
 	void init(S32 chunk_size);
 	virtual void cleanup();
 
-	virtual S32 startSend (U64 xfer_id, const LLHost &remote_host);
+	virtual S32 startSend(U64 xfer_id, const LLHost &remote_host);
+	virtual void closeFileHandle();
+	virtual S32 reopenFileHandle();
 	virtual void sendPacket(S32 packet_num);
 	virtual void sendNextPacket();
 	virtual void resendLastPacket();
diff --git a/indra/llmessage/llxfer_file.cpp b/indra/llmessage/llxfer_file.cpp
index 8e2ed890e7..7fd4222fb7 100644
--- a/indra/llmessage/llxfer_file.cpp
+++ b/indra/llmessage/llxfer_file.cpp
@@ -102,12 +102,12 @@ void LLXfer_File::cleanup ()
 
 	if (mDeleteLocalOnCompletion)
 	{
-		LL_DEBUGS() << "Removing file: " << mLocalFilename << LL_ENDL;
+		LL_DEBUGS("Xfer") << "Removing file: " << mLocalFilename << LL_ENDL;
 		LLFile::remove(mLocalFilename, ENOENT);
 	}
 	else
 	{
-		LL_DEBUGS() << "Keeping local file: " << mLocalFilename << LL_ENDL;
+		LL_DEBUGS("Xfer") << "Keeping local file: " << mLocalFilename << LL_ENDL;
 	}
 
 	LLXfer::cleanup();
@@ -139,7 +139,7 @@ S32 LLXfer_File::initializeRequest(U64 xfer_id,
 	mCallbackDataHandle = user_data;
 	mCallbackResult = LL_ERR_NOERR;
 
-	LL_INFOS() << "Requesting xfer from " << remote_host << " for file: " << mLocalFilename << LL_ENDL;
+	LL_INFOS("Xfer") << "Requesting xfer from " << remote_host << " for file: " << mLocalFilename << LL_ENDL;
 
 	if (mBuffer)
 	{
@@ -167,6 +167,7 @@ S32 LLXfer_File::startDownload()
 		fclose(mFp);
 		mFp = NULL;
 
+		// tbd - is it premature to send this message if the queue is backed up?
 		gMessageSystem->newMessageFast(_PREHASH_RequestXfer);
 		gMessageSystem->nextBlockFast(_PREHASH_XferID);
 		gMessageSystem->addU64Fast(_PREHASH_ID, mID);
@@ -182,7 +183,7 @@ S32 LLXfer_File::startDownload()
 	}
 	else
 	{
-		LL_WARNS() << "Couldn't create file to be received!" << LL_ENDL;
+		LL_WARNS("Xfer") << "Couldn't create file to be received!" << LL_ENDL;
 		retval = -1;
 	}
 
@@ -206,7 +207,8 @@ S32 LLXfer_File::startSend (U64 xfer_id, const LLHost &remote_host)
 
 	mBufferLength = 0;
 	mBufferStartOffset = 0;	
-	
+
+	// We leave the file open, assuming we'll start reading and sending soon
 	mFp = LLFile::fopen(mLocalFilename,"rb");		/* Flawfinder : ignore */
 	if (mFp)
 	{
@@ -223,7 +225,7 @@ S32 LLXfer_File::startSend (U64 xfer_id, const LLHost &remote_host)
 	}
 	else
 	{
-		LL_INFOS() << "Warning: " << mLocalFilename << " not found." << LL_ENDL;
+		LL_INFOS("Xfer") << "Warning: " << mLocalFilename << " not found." << LL_ENDL;
 		return (LL_ERR_FILE_NOT_FOUND);
 	}
 
@@ -233,6 +235,36 @@ S32 LLXfer_File::startSend (U64 xfer_id, const LLHost &remote_host)
 }
 
 ///////////////////////////////////////////////////////////
+void LLXfer_File::closeFileHandle()
+{
+	if (mFp)
+	{
+		fclose(mFp);
+		mFp = NULL;
+	}
+}
+
+///////////////////////////////////////////////////////////
+
+S32 LLXfer_File::reopenFileHandle()
+{
+	S32 retval = LL_ERR_NOERR;  // presume success
+
+	if (mFp == NULL)
+	{
+		mFp = LLFile::fopen(mLocalFilename,"rb");		/* Flawfinder : ignore */
+		if (mFp == NULL)
+		{
+			LL_INFOS("Xfer") << "Warning: " << mLocalFilename << " not found when re-opening file" << LL_ENDL;
+			retval = LL_ERR_FILE_NOT_FOUND;
+		}
+	}
+
+	return retval;
+}
+
+
+///////////////////////////////////////////////////////////
 
 S32 LLXfer_File::getMaxBufferSize ()
 {
@@ -279,18 +311,21 @@ S32 LLXfer_File::flush()
 	{
 		if (mFp)
 		{
-			LL_ERRS() << "Overwriting open file pointer!" << LL_ENDL;
+			LL_ERRS("Xfer") << "Overwriting open file pointer!" << LL_ENDL;
 		}
 		mFp = LLFile::fopen(mTempFilename,"a+b");		/* Flawfinder : ignore */
 
 		if (mFp)
 		{
-			if (fwrite(mBuffer,1,mBufferLength,mFp) != mBufferLength)
+			S32 write_size = fwrite(mBuffer,1,mBufferLength,mFp);
+			if (write_size != mBufferLength)
 			{
-				LL_WARNS() << "Short write" << LL_ENDL;
+				LL_WARNS("Xfer") << "Non-matching write size, requested " << mBufferLength
+					<< " but wrote " << write_size
+					<< LL_ENDL;
 			}
 			
-//			LL_INFOS() << "******* wrote " << mBufferLength << " bytes of file xfer" << LL_ENDL;
+//			LL_INFOS("Xfer") << "******* wrote " << mBufferLength << " bytes of file xfer" << LL_ENDL;
 			fclose(mFp);
 			mFp = NULL;
 			
@@ -298,7 +333,7 @@ S32 LLXfer_File::flush()
 		}
 		else
 		{
-			LL_WARNS() << "LLXfer_File::flush() unable to open " << mTempFilename << " for writing!" << LL_ENDL;
+			LL_WARNS("Xfer") << "LLXfer_File::flush() unable to open " << mTempFilename << " for writing!" << LL_ENDL;
 			retval = LL_ERR_CANNOT_OPEN_FILE;
 		}
 	}
@@ -329,18 +364,18 @@ S32 LLXfer_File::processEOF()
 		{
 #if !LL_WINDOWS
 			S32 error_number = errno;
-			LL_INFOS() << "Rename failure (" << error_number << ") - "
+			LL_INFOS("Xfer") << "Rename failure (" << error_number << ") - "
 					<< mTempFilename << " to " << mLocalFilename << LL_ENDL;
 			if(EXDEV == error_number)
 			{
 				if(copy_file(mTempFilename, mLocalFilename) == 0)
 				{
-					LL_INFOS() << "Rename across mounts; copying+unlinking the file instead." << LL_ENDL;
+					LL_INFOS("Xfer") << "Rename across mounts; copying+unlinking the file instead." << LL_ENDL;
 					unlink(mTempFilename.c_str());
 				}
 				else
 				{
-					LL_WARNS() << "Copy failure - " << mTempFilename << " to "
+					LL_WARNS("Xfer") << "Copy failure - " << mTempFilename << " to "
 							<< mLocalFilename << LL_ENDL;
 				}
 			}
@@ -354,11 +389,11 @@ S32 LLXfer_File::processEOF()
 				//LL_WARNS() << "File " << mLocalFilename << " does "
 				//		<< (!fp ? "not" : "" ) << " exit." << LL_ENDL;
 				//if(fp) fclose(fp);
-				LL_WARNS() << "Rename fatally failed, can only handle EXDEV ("
+				LL_WARNS("Xfer") << "Rename fatally failed, can only handle EXDEV ("
 						<< EXDEV << ")" << LL_ENDL;
 			}
 #else
-			LL_WARNS() << "Rename failure - " << mTempFilename << " to "
+			LL_WARNS("Xfer") << "Rename failure - " << mTempFilename << " to "
 					<< mLocalFilename << LL_ENDL;
 #endif
 		}
@@ -437,3 +472,4 @@ S32 copy_file(const std::string& from, const std::string& to)
 	return rv;
 }
 #endif
+
diff --git a/indra/llmessage/llxfer_file.h b/indra/llmessage/llxfer_file.h
index a37dda6732..ab9374549e 100644
--- a/indra/llmessage/llxfer_file.h
+++ b/indra/llmessage/llxfer_file.h
@@ -61,8 +61,10 @@ class LLXfer_File : public LLXfer
 	virtual S32 startDownload();
 
 	virtual S32 processEOF();
-	
-	virtual S32 startSend (U64 xfer_id, const LLHost &remote_host);
+
+	virtual S32 startSend(U64 xfer_id, const LLHost &remote_host);
+	virtual void closeFileHandle();
+	virtual S32 reopenFileHandle();
 
 	virtual S32 suck(S32 start_position);
 	virtual S32 flush();
diff --git a/indra/llmessage/llxfer_mem.cpp b/indra/llmessage/llxfer_mem.cpp
index 3bea08f2e5..78a3e4f558 100644
--- a/indra/llmessage/llxfer_mem.cpp
+++ b/indra/llmessage/llxfer_mem.cpp
@@ -80,28 +80,6 @@ void LLXfer_Mem::setXferSize (S32 xfer_size)
 
 ///////////////////////////////////////////////////////////
 
-U64 LLXfer_Mem::registerXfer(U64 xfer_id, const void *datap, const S32 length)
-{
-	mID = xfer_id;
-
-	if (datap)
-	{
-		setXferSize(length);
-		if (mBuffer)
-		{
-			memcpy(mBuffer,datap,length);		/* Flawfinder : ignore */
-			mBufferLength = length;
-		}
-		else
-		{
-			xfer_id = 0;
-		}
-	}
-	
-	mStatus = e_LL_XFER_REGISTERED;
-	return (xfer_id);
-}
-
 S32 LLXfer_Mem::startSend (U64 xfer_id, const LLHost &remote_host)
 {
 	S32 retval = LL_ERR_NOERR;  // presume success
diff --git a/indra/llmessage/llxfer_mem.h b/indra/llmessage/llxfer_mem.h
index b5adf837df..d07779de87 100644
--- a/indra/llmessage/llxfer_mem.h
+++ b/indra/llmessage/llxfer_mem.h
@@ -53,7 +53,6 @@ class LLXfer_Mem : public LLXfer
 	virtual void cleanup();
 
 	virtual S32 startSend (U64 xfer_id, const LLHost &remote_host);
-	virtual U64 registerXfer(U64 xfer_id, const void *datap, const S32 length);
 	virtual void setXferSize (S32 data_size);
 
 	virtual S32 initializeRequest(U64 xfer_id,
diff --git a/indra/llmessage/llxfer_vfile.cpp b/indra/llmessage/llxfer_vfile.cpp
index 4a378d1d34..ddc24342f6 100644
--- a/indra/llmessage/llxfer_vfile.cpp
+++ b/indra/llmessage/llxfer_vfile.cpp
@@ -79,8 +79,20 @@ void LLXfer_VFile::init (LLVFS *vfs, const LLUUID &local_id, LLAssetType::EType
 
 void LLXfer_VFile::cleanup ()
 {
-	LLVFile file(mVFS, mTempID, mType, LLVFile::WRITE);
-	file.remove();
+	if (mTempID.notNull() &&
+		mDeleteTempFile)
+	{
+		if (mVFS->getExists(mTempID, mType))
+		{
+			LLVFile file(mVFS, mTempID, mType, LLVFile::WRITE);
+			file.remove();
+		}
+		else
+		{
+			LL_WARNS("Xfer") << "LLXfer_VFile::cleanup() can't open to delete VFS file " << mTempID << "." << LLAssetType::lookup(mType)		
+				<< ", mRemoteID is " << mRemoteID << LL_ENDL;
+		}
+	}
 
 	delete mVFile;
 	mVFile = NULL;
@@ -118,7 +130,7 @@ S32 LLXfer_VFile::initializeRequest(U64 xfer_id,
 
 	mName = llformat("VFile %s:%s", id_string.c_str(), LLAssetType::lookup(mType));
 
-	LL_INFOS() << "Requesting " << mName << LL_ENDL;
+	LL_INFOS("Xfer") << "Requesting " << mName << LL_ENDL;
 
 	if (mBuffer)
 	{
@@ -131,6 +143,7 @@ S32 LLXfer_VFile::initializeRequest(U64 xfer_id,
 	mBufferLength = 0;
 	mPacketNum = 0;
 	mTempID.generate();
+	mDeleteTempFile = TRUE;
  	mStatus = e_LL_XFER_PENDING;
 	return retval;
 }
@@ -140,7 +153,8 @@ S32 LLXfer_VFile::initializeRequest(U64 xfer_id,
 S32 LLXfer_VFile::startDownload()
 {
  	S32 retval = 0;  // presume success
-	LLVFile file(mVFS, mTempID, mType, LLVFile::APPEND);
+
+	// Don't need to create the file here, it will happen when data arrives
 
 	gMessageSystem->newMessageFast(_PREHASH_RequestXfer);
 	gMessageSystem->nextBlockFast(_PREHASH_XferID);
@@ -184,6 +198,8 @@ S32 LLXfer_VFile::startSend (U64 xfer_id, const LLHost &remote_host)
 
 		if (mVFile->getSize() <= 0)
 		{
+			LL_WARNS("Xfer") << "LLXfer_VFile::startSend() VFS file " << mLocalID << "." << LLAssetType::lookup(mType)		
+				<< " has unexpected file size of " << mVFile->getSize() << LL_ENDL;
 			delete mVFile;
 			mVFile = NULL;
 
@@ -198,6 +214,7 @@ S32 LLXfer_VFile::startSend (U64 xfer_id, const LLHost &remote_host)
 	}
 	else
 	{
+		LL_WARNS("Xfer") << "LLXfer_VFile::startSend() can't read VFS file " << mLocalID << "." << LLAssetType::lookup(mType) << LL_ENDL;
 		retval = LL_ERR_FILE_NOT_FOUND;
 	}
 
@@ -205,6 +222,41 @@ S32 LLXfer_VFile::startSend (U64 xfer_id, const LLHost &remote_host)
 }
 
 ///////////////////////////////////////////////////////////
+
+void LLXfer_VFile::closeFileHandle()
+{
+	if (mVFile)
+	{
+		delete mVFile;
+		mVFile = NULL;
+	}
+}
+
+///////////////////////////////////////////////////////////
+
+S32 LLXfer_VFile::reopenFileHandle()
+{
+	S32 retval = LL_ERR_NOERR;  // presume success
+
+	if (mVFile == NULL)
+	{
+		if (mVFS->getExists(mLocalID, mType))
+		{
+			mVFile = new LLVFile(mVFS, mLocalID, mType, LLVFile::READ);
+		}
+		else
+		{
+			LL_WARNS("Xfer") << "LLXfer_VFile::reopenFileHandle() can't read VFS file " << mLocalID << "." << LLAssetType::lookup(mType) << LL_ENDL;
+			retval = LL_ERR_FILE_NOT_FOUND;
+		}
+	}
+
+	return retval;
+}
+
+
+///////////////////////////////////////////////////////////
+
 void LLXfer_VFile::setXferSize (S32 xfer_size)
 {	
 	LLXfer::setXferSize(xfer_size);
@@ -236,8 +288,8 @@ S32 LLXfer_VFile::suck(S32 start_position)
 		// grab a buffer from the right place in the file
 		if (! mVFile->seek(start_position, 0))
 		{
-			LL_WARNS() << "VFile Xfer Can't seek to position " << start_position << ", file length " << mVFile->getSize() << LL_ENDL;
-			LL_WARNS() << "While sending file " << mLocalID << LL_ENDL;
+			LL_WARNS("Xfer") << "VFile Xfer Can't seek to position " << start_position << ", file length " << mVFile->getSize() << LL_ENDL;
+			LL_WARNS("Xfer") << "While sending file " << mLocalID << LL_ENDL;
 			return -1;
 		}
 		
@@ -288,12 +340,31 @@ S32 LLXfer_VFile::processEOF()
 
 	if (!mCallbackResult)
 	{
-		LLVFile file(mVFS, mTempID, mType, LLVFile::WRITE);
-		if (! file.rename(mLocalID, mType))
+		if (mVFS->getExists(mTempID, mType))
 		{
-			LL_INFOS() << "copy from temp file failed: unable to rename to " << mLocalID << LL_ENDL;
+			LLVFile file(mVFS, mTempID, mType, LLVFile::WRITE);
+			if (!file.rename(mLocalID, mType))
+			{
+				LL_WARNS("Xfer") << "VFS rename of temp file failed: unable to rename " << mTempID << " to " << mLocalID << LL_ENDL;
+			}
+			else
+			{					
+				#ifdef VFS_SPAM
+				// Debugging spam
+				LL_INFOS("Xfer") << "VFS rename of temp file done: renamed " << mTempID << " to " << mLocalID 
+					<< " LLVFile size is " << file.getSize()
+					<< LL_ENDL;
+				#endif				
+				
+				// Rename worked: the original file is gone.   Clear mDeleteTempFile
+				// so we don't attempt to delete the file in cleanup()
+				mDeleteTempFile = FALSE;
+			}
+		}
+		else
+		{
+			LL_WARNS("Xfer") << "LLXfer_VFile::processEOF() can't open for renaming VFS file " << mTempID << "." << LLAssetType::lookup(mType) << LL_ENDL;
 		}
-
 	}
 
 	if (mVFile)
@@ -336,3 +407,4 @@ U32 LLXfer_VFile::getXferTypeTag()
 {
 	return LLXfer::XFER_VFILE;
 }
+
diff --git a/indra/llmessage/llxfer_vfile.h b/indra/llmessage/llxfer_vfile.h
index 048bf49dcc..5bf9a5cfba 100644
--- a/indra/llmessage/llxfer_vfile.h
+++ b/indra/llmessage/llxfer_vfile.h
@@ -47,6 +47,8 @@ class LLXfer_VFile : public LLXfer
 
 	std::string mName;
 
+	BOOL	mDeleteTempFile;
+
  public:
 	LLXfer_VFile ();
 	LLXfer_VFile (LLVFS *vfs, const LLUUID &local_id, LLAssetType::EType type);
@@ -66,8 +68,10 @@ class LLXfer_VFile : public LLXfer
 	virtual S32 startDownload();
 
 	virtual S32 processEOF();
-	
-	virtual S32 startSend (U64 xfer_id, const LLHost &remote_host);
+
+	virtual S32 startSend(U64 xfer_id, const LLHost &remote_host);
+	virtual void closeFileHandle();
+	virtual S32 reopenFileHandle();
 
 	virtual S32 suck(S32 start_position);
 	virtual S32 flush();
diff --git a/indra/llmessage/llxfermanager.cpp b/indra/llmessage/llxfermanager.cpp
index 2ceb64ce8f..4cea886c8a 100644
--- a/indra/llmessage/llxfermanager.cpp
+++ b/indra/llmessage/llxfermanager.cpp
@@ -44,9 +44,15 @@ const S32 LL_PACKET_RETRY_LIMIT = 10;            // packet retransmission limit
 const S32 LL_DEFAULT_MAX_SIMULTANEOUS_XFERS = 10;
 const S32 LL_DEFAULT_MAX_REQUEST_FIFO_XFERS = 1000;
 
-#define LL_XFER_PROGRESS_MESSAGES 0
-#define LL_XFER_TEST_REXMIT       0
+// Kills the connection if a viewer download queue hits this many requests backed up
+// Also set in simulator.xml at "hard_limit_outgoing_xfers_per_circuit"
+const S32 LL_DEFAULT_MAX_HARD_LIMIT_SIMULTANEOUS_XFERS = 500;	
 
+// Use this to show sending some ConfirmXferPacket messages
+//#define LL_XFER_PROGRESS_MESSAGES 1
+
+// Use this for lots of diagnostic spam
+//#define LL_XFER_DIAGNOISTIC_LOGGING 1
 
 ///////////////////////////////////////////////////////////
 
@@ -66,10 +72,10 @@ LLXferManager::~LLXferManager ()
 
 void LLXferManager::init (LLVFS *vfs)
 {
-	mSendList = NULL;
-	mReceiveList = NULL;
+	cleanup();
 
 	setMaxOutgoingXfersPerCircuit(LL_DEFAULT_MAX_SIMULTANEOUS_XFERS);
+	setHardLimitOutgoingXfersPerCircuit(LL_DEFAULT_MAX_HARD_LIMIT_SIMULTANEOUS_XFERS);
 	setMaxIncomingXfers(LL_DEFAULT_MAX_REQUEST_FIFO_XFERS);
 
 	mVFS = vfs;
@@ -83,29 +89,14 @@ void LLXferManager::init (LLVFS *vfs)
 
 void LLXferManager::cleanup ()
 {
-	LLXfer *xferp;
-	LLXfer *delp;
-
 	for_each(mOutgoingHosts.begin(), mOutgoingHosts.end(), DeletePointer());
 	mOutgoingHosts.clear();
 
-	delp = mSendList;
-	while (delp)
-	{
-		xferp = delp->mNext;
-		delete delp;
-		delp = xferp;
-	}
-	mSendList = NULL;
+	for_each(mSendList.begin(), mSendList.end(), DeletePointer());
+	mSendList.clear();
 
-	delp = mReceiveList;
-	while (delp)
-	{
-		xferp = delp->mNext;
-		delete delp;
-		delp = xferp;
-	}
-	mReceiveList = NULL;
+	for_each(mReceiveList.begin(), mReceiveList.end(), DeletePointer());
+	mReceiveList.clear();
 }
 
 ///////////////////////////////////////////////////////////
@@ -122,6 +113,11 @@ void LLXferManager::setMaxOutgoingXfersPerCircuit(S32 max_num)
 	mMaxOutgoingXfersPerCircuit = max_num;
 }
 
+void LLXferManager::setHardLimitOutgoingXfersPerCircuit(S32 max_num)
+{
+	mHardLimitOutgoingXfersPerCircuit = max_num;
+}
+
 void LLXferManager::setUseAckThrottling(const BOOL use)
 {
 	mUseAckThrottling = use;
@@ -140,6 +136,11 @@ void LLXferManager::setAckThrottleBPS(const F32 bps)
 	F32 actual_rate = llmax(min_bps*1.1f, bps);
 	LL_DEBUGS("AppInit") << "LLXferManager ack throttle min rate: " << min_bps << LL_ENDL;
 	LL_DEBUGS("AppInit") << "LLXferManager ack throttle actual rate: " << actual_rate << LL_ENDL;
+	#ifdef LL_XFER_DIAGNOISTIC_LOGGING
+	LL_INFOS("Xfer") << "LLXferManager ack throttle min rate: " << min_bps << LL_ENDL;
+	LL_INFOS("Xfer") << "LLXferManager ack throttle actual rate: " << actual_rate << LL_ENDL;
+	#endif // LL_XFER_DIAGNOISTIC_LOGGING
+
 	mAckThrottle.setRate(actual_rate);
 }
 
@@ -148,45 +149,71 @@ void LLXferManager::setAckThrottleBPS(const F32 bps)
 
 void LLXferManager::updateHostStatus()
 {
-    LLXfer *xferp;
-	LLHostStatus *host_statusp = NULL;
-
+	// Clear the outgoing host list
 	for_each(mOutgoingHosts.begin(), mOutgoingHosts.end(), DeletePointer());
 	mOutgoingHosts.clear();
-
-	for (xferp = mSendList; xferp; xferp = xferp->mNext)
+	
+	// Loop through all outgoing xfers and re-build mOutgoingHosts
+	for (xfer_list_t::iterator send_iter = mSendList.begin();
+			send_iter != mSendList.end(); ++send_iter)
 	{
+		LLHostStatus *host_statusp = NULL;
 		for (status_list_t::iterator iter = mOutgoingHosts.begin();
 			 iter != mOutgoingHosts.end(); ++iter)
 		{
-			host_statusp = *iter;
-			if (host_statusp->mHost == xferp->mRemoteHost)
-			{
+			if ((*iter)->mHost == (*send_iter)->mRemoteHost)
+			{	// Already have this host
+				host_statusp = *iter;
 				break;
 			}
 		}
 		if (!host_statusp)
-		{
+		{	// Don't have this host, so add it
 			host_statusp = new LLHostStatus();
 			if (host_statusp)
 			{
-				host_statusp->mHost = xferp->mRemoteHost;
+				host_statusp->mHost = (*send_iter)->mRemoteHost;
 				mOutgoingHosts.push_front(host_statusp);
 			}
 		}
 		if (host_statusp)
-		{
-			if (xferp->mStatus == e_LL_XFER_PENDING)
+		{	// Do the accounting
+			if ((*send_iter)->mStatus == e_LL_XFER_PENDING)
 			{
 				host_statusp->mNumPending++;
 			}
-			else if (xferp->mStatus == e_LL_XFER_IN_PROGRESS)
+			else if ((*send_iter)->mStatus == e_LL_XFER_IN_PROGRESS)
 			{
 				host_statusp->mNumActive++;
 			}
 		}
-		
 	}	
+
+#ifdef LL_XFER_DIAGNOISTIC_LOGGING
+	for (xfer_list_t::iterator send_iter = mSendList.begin();
+			send_iter != mSendList.end(); ++send_iter)
+	{
+		LLXfer * xferp = *send_iter;
+		LL_INFOS("Xfer") << "xfer to host " << xferp->mRemoteHost
+			<< " is " << xferp->mXferSize << " bytes"
+			<< ", status " << (S32)(xferp->mStatus)
+			<< ", waiting for ACK: " << (S32)(xferp->mWaitingForACK)
+			<< " in frame " << (S32) LLFrameTimer::getFrameCount()
+			<< LL_ENDL;
+	}
+
+	for (status_list_t::iterator iter = mOutgoingHosts.begin();
+		 iter != mOutgoingHosts.end(); ++iter)
+	{
+		LL_INFOS("Xfer") << "LLXfer host " << (*iter)->mHost.getIPandPort() 
+			<< " has " << (*iter)->mNumActive
+			<< " active, " << (*iter)->mNumPending
+			<< " pending" 
+			<< " in frame " << (S32) LLFrameTimer::getFrameCount()
+			<< LL_ENDL;
+	}
+#endif // LL_XFER_DIAGNOISTIC_LOGGING
+
 }
 
 ///////////////////////////////////////////////////////////
@@ -196,27 +223,28 @@ void LLXferManager::printHostStatus()
 	LLHostStatus *host_statusp = NULL;
 	if (!mOutgoingHosts.empty())
 	{
-		LL_INFOS() << "Outgoing Xfers:" << LL_ENDL;
+		LL_INFOS("Xfer") << "Outgoing Xfers:" << LL_ENDL;
 
 		for (status_list_t::iterator iter = mOutgoingHosts.begin();
 			 iter != mOutgoingHosts.end(); ++iter)
 		{
 			host_statusp = *iter;
-			LL_INFOS() << "    " << host_statusp->mHost << "  active: " << host_statusp->mNumActive << "  pending: " << host_statusp->mNumPending << LL_ENDL;
+			LL_INFOS("Xfer") << "    " << host_statusp->mHost << "  active: " << host_statusp->mNumActive << "  pending: " << host_statusp->mNumPending << LL_ENDL;
 		}
 	}	
 }
 
 ///////////////////////////////////////////////////////////
 
-LLXfer *LLXferManager::findXfer (U64 id, LLXfer *list_head)
+LLXfer * LLXferManager::findXferByID(U64 id, xfer_list_t & xfer_list)
 {
-    LLXfer *xferp;
-	for (xferp = list_head; xferp; xferp = xferp->mNext)
+	for (xfer_list_t::iterator iter = xfer_list.begin();
+		 iter != xfer_list.end();
+		 ++iter)
 	{
-		if (xferp->mID == id)
+		if ((*iter)->mID == id)
 		{
-			return(xferp);
+			return(*iter);
 		}
 	}
 	return(NULL);
@@ -225,29 +253,34 @@ LLXfer *LLXferManager::findXfer (U64 id, LLXfer *list_head)
 
 ///////////////////////////////////////////////////////////
 
-void LLXferManager::removeXfer (LLXfer *delp, LLXfer **list_head)
+// WARNING:  this invalidates iterators from xfer_list
+void LLXferManager::removeXfer(LLXfer *delp, xfer_list_t & xfer_list)
 {
-	// This function assumes that delp will only occur in the list
-	// zero or one times.
 	if (delp)
-	{
-		if (*list_head == delp)
+	{	
+		std::string direction = "send";
+		if (&xfer_list == &mReceiveList)
 		{
-			*list_head = delp->mNext;
-			delete (delp);
+			direction = "receive";
 		}
-		else
+
+		// This assumes that delp will occur in the list once at most
+		// Find the pointer in the list
+		for (xfer_list_t::iterator iter = xfer_list.begin();
+			 iter != xfer_list.end();
+			 ++iter)
 		{
-			LLXfer *xferp = *list_head;
-			while (xferp->mNext)
+			if ((*iter) == delp)
 			{
-				if (xferp->mNext == delp)
-				{
-					xferp->mNext = delp->mNext;
-					delete (delp);
-					break;
-				}
-				xferp = xferp->mNext;
+				LL_DEBUGS("Xfer") << "Deleting xfer to host " << (*iter)->mRemoteHost
+					<< " of " << (*iter)->mXferSize << " bytes"
+					<< ", status " << (S32)((*iter)->mStatus)
+					<< " from the " << direction << " list"
+					<< LL_ENDL;
+
+				xfer_list.erase(iter);
+				delete (delp);
+				break;
 			}
 		}
 	}
@@ -255,35 +288,30 @@ void LLXferManager::removeXfer (LLXfer *delp, LLXfer **list_head)
 
 ///////////////////////////////////////////////////////////
 
-U32 LLXferManager::numActiveListEntries(LLXfer *list_head)
+LLHostStatus * LLXferManager::findHostStatus(const LLHost &host)
 {
-	U32 num_entries = 0;
+	LLHostStatus *host_statusp = NULL;
 
-	while (list_head)
+	for (status_list_t::iterator iter = mOutgoingHosts.begin();
+		 iter != mOutgoingHosts.end(); ++iter)
 	{
-		if (list_head->mStatus == e_LL_XFER_IN_PROGRESS) 
+		host_statusp = *iter;
+		if (host_statusp->mHost == host)
 		{
-			num_entries++;
+			return (host_statusp);
 		}
-		list_head = list_head->mNext;
 	}
-	return(num_entries);
+	return 0;
 }
 
 ///////////////////////////////////////////////////////////
-
+ 
 S32 LLXferManager::numPendingXfers(const LLHost &host)
 {
-	LLHostStatus *host_statusp = NULL;
-
-	for (status_list_t::iterator iter = mOutgoingHosts.begin();
-		 iter != mOutgoingHosts.end(); ++iter)
+	LLHostStatus *host_statusp = findHostStatus(host);
+	if (host_statusp)
 	{
-		host_statusp = *iter;
-		if (host_statusp->mHost == host)
-		{
-			return (host_statusp->mNumPending);
-		}
+		return host_statusp->mNumPending;
 	}
 	return 0;
 }
@@ -292,16 +320,10 @@ S32 LLXferManager::numPendingXfers(const LLHost &host)
 
 S32 LLXferManager::numActiveXfers(const LLHost &host)
 {
-	LLHostStatus *host_statusp = NULL;
-
-	for (status_list_t::iterator iter = mOutgoingHosts.begin();
-		 iter != mOutgoingHosts.end(); ++iter)
+	LLHostStatus *host_statusp = findHostStatus(host);
+	if (host_statusp)
 	{
-		host_statusp = *iter;
-		if (host_statusp->mHost == host)
-		{
-			return (host_statusp->mNumActive);
-		}
+		return host_statusp->mNumActive;
 	}
 	return 0;
 }
@@ -372,35 +394,6 @@ BOOL LLXferManager::isLastPacket(S32 packet_num)
 
 ///////////////////////////////////////////////////////////
 
-U64 LLXferManager::registerXfer(const void *datap, const S32 length)
-{
-	LLXfer *xferp;
-	U64 xfer_id = getNextID();
-
-	xferp = (LLXfer *) new LLXfer_Mem();
-	if (xferp)
-	{
-		xferp->mNext = mSendList;
-		mSendList = xferp;
-
-		xfer_id = ((LLXfer_Mem *)xferp)->registerXfer(xfer_id, datap,length);
-
-		if (!xfer_id)
-		{
-			removeXfer(xferp,&mSendList);
-		}
-	}
-	else
-	{
-		LL_ERRS() << "Xfer allocation error" << LL_ENDL;
-		xfer_id = 0;
-	}	
-
-    return(xfer_id);
-}
-
-///////////////////////////////////////////////////////////
-
 U64 LLXferManager::requestFile(const std::string& local_filename,
 								const std::string& remote_filename,
 								ELLPath remote_path,
@@ -411,43 +404,46 @@ U64 LLXferManager::requestFile(const std::string& local_filename,
 								BOOL is_priority,
 								BOOL use_big_packets)
 {
-	LLXfer *xferp;
+	LLXfer_File* file_xfer_p = NULL;
 
-	for (xferp = mReceiveList; xferp ; xferp = xferp->mNext)
+	// First check to see if it's already requested
+	for (xfer_list_t::iterator iter = mReceiveList.begin();
+			iter != mReceiveList.end(); ++iter)
 	{
-		if (xferp->getXferTypeTag() == LLXfer::XFER_FILE
-			&& (((LLXfer_File*)xferp)->matchesLocalFilename(local_filename))
-			&& (((LLXfer_File*)xferp)->matchesRemoteFilename(remote_filename, remote_path))
-			&& (remote_host == xferp->mRemoteHost)
-			&& (callback == xferp->mCallback)
-			&& (user_data == xferp->mCallbackDataHandle))
-
+		if ((*iter)->getXferTypeTag() == LLXfer::XFER_FILE)
 		{
-			// cout << "requested a xfer already in progress" << endl;
-			return xferp->mID;
+			file_xfer_p = (LLXfer_File*)(*iter);
+			if (file_xfer_p->matchesLocalFilename(local_filename)
+				&& file_xfer_p->matchesRemoteFilename(remote_filename, remote_path)
+				&& (remote_host == file_xfer_p->mRemoteHost)
+				&& (callback == file_xfer_p->mCallback)
+				&& (user_data == file_xfer_p->mCallbackDataHandle))
+			{
+				// Already have the request	(already in progress)
+				return (*iter)->mID;
+			}
 		}
 	}
 
 	U64 xfer_id = 0;
 
 	S32 chunk_size = use_big_packets ? LL_XFER_LARGE_PAYLOAD : -1;
-	xferp = (LLXfer *) new LLXfer_File(chunk_size);
-	if (xferp)
+	file_xfer_p = new LLXfer_File(chunk_size);
+	if (file_xfer_p)
 	{
-		addToList(xferp, mReceiveList, is_priority);
+		addToList(file_xfer_p, mReceiveList, is_priority);
 
 		// Remove any file by the same name that happens to be lying
 		// around.
 		// Note: according to AaronB, this is here to deal with locks on files that were
 		// in transit during a crash,
-		if( delete_remote_on_completion
-			&& (remote_filename.substr(remote_filename.length()-4) == ".tmp")
-			&& gDirUtilp->fileExists(local_filename))
+		if(delete_remote_on_completion &&
+		   (remote_filename.substr(remote_filename.length()-4) == ".tmp"))
 		{
 			LLFile::remove(local_filename, ENOENT);
 		}
 		xfer_id = getNextID();
-		((LLXfer_File *)xferp)->initializeRequest(
+		file_xfer_p->initializeRequest(
 			xfer_id,
 			local_filename,
 			remote_filename,
@@ -459,39 +455,11 @@ U64 LLXferManager::requestFile(const std::string& local_filename,
 	}
 	else
 	{
-		LL_ERRS() << "Xfer allocation error" << LL_ENDL;
+		LL_ERRS("Xfer") << "Xfer allocation error" << LL_ENDL;
 	}
 	return xfer_id;
 }
 
-void LLXferManager::requestFile(const std::string& remote_filename,
-								ELLPath remote_path,
-								const LLHost& remote_host,
-								BOOL delete_remote_on_completion,
-								void (*callback)(void*,S32,void**,S32,LLExtStat),
-								void** user_data,
-								BOOL is_priority)
-{
-	LLXfer *xferp;
-
-	xferp = (LLXfer *) new LLXfer_Mem();
-	if (xferp)
-	{
-		addToList(xferp, mReceiveList, is_priority);
-		((LLXfer_Mem *)xferp)->initializeRequest(getNextID(),
-												 remote_filename, 
-												 remote_path,
-												 remote_host,
-												 delete_remote_on_completion,
-												 callback, user_data);
-		startPendingDownloads();
-	}
-	else
-	{
-		LL_ERRS() << "Xfer allocation error" << LL_ENDL;
-	}
-}
-
 void LLXferManager::requestVFile(const LLUUID& local_id,
 								 const LLUUID& remote_id,
 								 LLAssetType::EType type, LLVFS* vfs,
@@ -500,28 +468,46 @@ void LLXferManager::requestVFile(const LLUUID& local_id,
 								 void** user_data,
 								 BOOL is_priority)
 {
-	LLXfer *xferp;
-
-	for (xferp = mReceiveList; xferp ; xferp = xferp->mNext)
-	{
-		if (xferp->getXferTypeTag() == LLXfer::XFER_VFILE
-			&& (((LLXfer_VFile*)xferp)->matchesLocalFile(local_id, type))
-			&& (((LLXfer_VFile*)xferp)->matchesRemoteFile(remote_id, type))
-			&& (remote_host == xferp->mRemoteHost)
-			&& (callback == xferp->mCallback)
-			&& (user_data == xferp->mCallbackDataHandle))
+	LLXfer_VFile * xfer_p = NULL;
 
+	for (xfer_list_t::iterator iter = mReceiveList.begin();
+			iter != mReceiveList.end(); ++iter)
+	{	// Find any matching existing requests
+		if ((*iter)->getXferTypeTag() == LLXfer::XFER_VFILE)
 		{
-			// cout << "requested a xfer already in progress" << endl;
-			return;
+			xfer_p = (LLXfer_VFile*) (*iter);
+			if (xfer_p->matchesLocalFile(local_id, type)
+				&& xfer_p->matchesRemoteFile(remote_id, type)
+				&& (remote_host == xfer_p->mRemoteHost)
+				&& (callback == xfer_p->mCallback)
+				&& (user_data == xfer_p->mCallbackDataHandle))
+
+			{	// Have match, don't add a duplicate
+				#ifdef LL_XFER_DIAGNOISTIC_LOGGING
+				LL_INFOS("Xfer") << "Dropping duplicate xfer request for " << remote_id
+					<< " on " << remote_host.getIPandPort()
+					<< " local id " << local_id
+					<< LL_ENDL;
+				#endif	// LL_XFER_DIAGNOISTIC_LOGGING
+
+				return;
+			}
 		}
 	}
 
-	xferp = (LLXfer *) new LLXfer_VFile();
-	if (xferp)
+	xfer_p = new LLXfer_VFile();
+	if (xfer_p)
 	{
-		addToList(xferp, mReceiveList, is_priority);
-		((LLXfer_VFile *)xferp)->initializeRequest(getNextID(),
+		#ifdef LL_XFER_DIAGNOISTIC_LOGGING
+		LL_INFOS("Xfer") << "Starting file xfer for " << remote_id
+			<< " type " << LLAssetType::lookupHumanReadable(type)
+			<< " from " << xfer_p->mRemoteHost.getIPandPort()
+			<< ", local id " << local_id
+			<< LL_ENDL;
+		#endif	// LL_XFER_DIAGNOISTIC_LOGGING
+
+		addToList(xfer_p, mReceiveList, is_priority);
+		((LLXfer_VFile *)xfer_p)->initializeRequest(getNextID(),
 			vfs,
 			local_id,
 			remote_id,
@@ -533,78 +519,18 @@ void LLXferManager::requestVFile(const LLUUID& local_id,
 	}
 	else
 	{
-		LL_ERRS() << "Xfer allocation error" << LL_ENDL;
-	}
-
-}
-
-/*
-void LLXferManager::requestXfer(
-								const std::string& local_filename, 
-								BOOL delete_remote_on_completion,
-								U64 xfer_id, 
-								const LLHost &remote_host, 
-								void (*callback)(void **,S32),
-								void **user_data)
-{
-	LLXfer *xferp;
-
-	for (xferp = mReceiveList; xferp ; xferp = xferp->mNext)
-	{
-		if (xferp->getXferTypeTag() == LLXfer::XFER_FILE
-			&& (((LLXfer_File*)xferp)->matchesLocalFilename(local_filename))
-			&& (xfer_id == xferp->mID)
-			&& (remote_host == xferp->mRemoteHost)
-			&& (callback == xferp->mCallback)
-			&& (user_data == xferp->mCallbackDataHandle))
-
-		{
-			// cout << "requested a xfer already in progress" << endl;
-			return;
-		}
+		LL_ERRS("Xfer") << "Xfer allocation error" << LL_ENDL;
 	}
 
-	xferp = (LLXfer *) new LLXfer_File();
-	if (xferp)
-	{
-		xferp->mNext = mReceiveList;
-		mReceiveList = xferp;
-
-		((LLXfer_File *)xferp)->initializeRequest(xfer_id,local_filename,"",LL_PATH_NONE,remote_host,delete_remote_on_completion,callback,user_data);
-		startPendingDownloads();
-	}
-	else
-	{
-		LL_ERRS() << "Xfer allcoation error" << LL_ENDL;
-	}
 }
 
-void LLXferManager::requestXfer(U64 xfer_id, const LLHost &remote_host, BOOL delete_remote_on_completion, void (*callback)(void *,S32,void **,S32),void **user_data)
-{
-	LLXfer *xferp;
-
-	xferp = (LLXfer *) new LLXfer_Mem();
-	if (xferp)
-	{
-		xferp->mNext = mReceiveList;
-		mReceiveList = xferp;
-
-		((LLXfer_Mem *)xferp)->initializeRequest(xfer_id,"",LL_PATH_NONE,remote_host,delete_remote_on_completion,callback,user_data);
-		startPendingDownloads();
-	}
-	else
-	{
-		LL_ERRS() << "Xfer allcoation error" << LL_ENDL;
-	}
-}
-*/
 ///////////////////////////////////////////////////////////
 
 void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user_data*/)
 {
 	// there's sometimes an extra 4 bytes added to an xfer payload
 	const S32 BUF_SIZE = LL_XFER_LARGE_PAYLOAD + 4;
-	char fdata_buf[LL_XFER_LARGE_PAYLOAD + 4];		/* Flawfinder : ignore */
+	char fdata_buf[BUF_SIZE];		/* Flawfinder : ignore */
 	S32 fdata_size;
 	U64 id;
 	S32 packetnum;
@@ -614,14 +540,24 @@ void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user
 	mesgsys->getS32Fast(_PREHASH_XferID, _PREHASH_Packet, packetnum);
 
 	fdata_size = mesgsys->getSizeFast(_PREHASH_DataPacket,_PREHASH_Data);
-	mesgsys->getBinaryDataFast(_PREHASH_DataPacket, _PREHASH_Data, fdata_buf, 0, 0, BUF_SIZE);
-
-	xferp = findXfer(id, mReceiveList);
+	if (fdata_size < 0 ||
+		fdata_size > BUF_SIZE)
+	{
+		char U64_BUF[MAX_STRING];		/* Flawfinder : ignore */
+		LL_WARNS("Xfer") << "Received invalid xfer data size of " << fdata_size
+			<< " in packet number " << packetnum 
+			<< " from " << mesgsys->getSender()
+			<< " for xfer id: " << U64_to_str(id, U64_BUF, sizeof(U64_BUF)) 
+			<< LL_ENDL;
+		return;
+	}
+	mesgsys->getBinaryDataFast(_PREHASH_DataPacket, _PREHASH_Data, fdata_buf, fdata_size, 0, BUF_SIZE);
 
-	if (!xferp) 
+	xferp = findXferByID(id, mReceiveList);
+	if (!xferp)
 	{
 		char U64_BUF[MAX_STRING];		/* Flawfinder : ignore */
-		LL_INFOS() << "received xfer data from " << mesgsys->getSender()
+		LL_WARNS("Xfer") << "received xfer data from " << mesgsys->getSender()
 			<< " for non-existent xfer id: "
 			<< U64_to_str(id, U64_BUF, sizeof(U64_BUF)) << LL_ENDL;
 		return;
@@ -634,11 +570,11 @@ void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user
 		// confirm it if it was a resend of the last one, since the confirmation might have gotten dropped
 		if (decodePacketNum(packetnum) == (xferp->mPacketNum - 1))
 		{
-			LL_INFOS() << "Reconfirming xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet " << packetnum << LL_ENDL; 			sendConfirmPacket(mesgsys, id, decodePacketNum(packetnum), mesgsys->getSender());
+			LL_INFOS("Xfer") << "Reconfirming xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet " << packetnum << LL_ENDL; 			sendConfirmPacket(mesgsys, id, decodePacketNum(packetnum), mesgsys->getSender());
 		}
 		else
 		{
-			LL_INFOS() << "Ignoring xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " recv'd packet " << packetnum << "; expecting " << xferp->mPacketNum << LL_ENDL;
+			LL_INFOS("Xfer") << "Ignoring xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " recv'd packet " << packetnum << "; expecting " << xferp->mPacketNum << LL_ENDL;
 		}
 		return;		
 	}
@@ -663,7 +599,7 @@ void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user
 	if (result == LL_ERR_CANNOT_OPEN_FILE)
 	{
 			xferp->abort(LL_ERR_CANNOT_OPEN_FILE);
-			removeXfer(xferp,&mReceiveList);
+			removeXfer(xferp,mReceiveList);
 			startPendingDownloads();
 			return;		
 	}
@@ -688,7 +624,7 @@ void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user
 	if (isLastPacket(packetnum))
 	{
 		xferp->processEOF();
-		removeXfer(xferp,&mReceiveList);
+		removeXfer(xferp,mReceiveList);
 		startPendingDownloads();
 	}
 }
@@ -697,7 +633,7 @@ void LLXferManager::processReceiveData (LLMessageSystem *mesgsys, void ** /*user
 
 void LLXferManager::sendConfirmPacket (LLMessageSystem *mesgsys, U64 id, S32 packetnum, const LLHost &remote_host)
 {
-#if LL_XFER_PROGRESS_MESSAGES
+#ifdef LL_XFER_PROGRESS_MESSAGES
 	if (!(packetnum % 50))
 	{
 		cout << "confirming xfer packet #" << packetnum << endl;
@@ -708,6 +644,7 @@ void LLXferManager::sendConfirmPacket (LLMessageSystem *mesgsys, U64 id, S32 pac
 	mesgsys->addU64Fast(_PREHASH_ID, id);
 	mesgsys->addU32Fast(_PREHASH_Packet, packetnum);
 
+	// Ignore a circuit failure here, we'll catch it with another message
 	mesgsys->sendMessage(remote_host);
 }
 
@@ -746,6 +683,28 @@ bool LLXferManager::validateFileForTransfer(const std::string& filename)
 	return find_and_remove(mExpectedTransfers, filename);
 }
 
+/* Present in fireengine, not used by viewer
+void LLXferManager::expectVFileForRequest(const std::string& filename)
+{
+	mExpectedVFileRequests.insert(filename);
+}
+
+bool LLXferManager::validateVFileForRequest(const std::string& filename)
+{
+	return find_and_remove(mExpectedVFileRequests, filename);
+}
+
+void LLXferManager::expectVFileForTransfer(const std::string& filename)
+{
+	mExpectedVFileTransfers.insert(filename);
+}
+
+bool LLXferManager::validateVFileForTransfer(const std::string& filename)
+{
+	return find_and_remove(mExpectedVFileTransfers, filename);
+}
+*/
+
 static bool remove_prefix(std::string& filename, const std::string& prefix)
 {
 	if (std::equal(prefix.begin(), prefix.end(), filename.begin()))
@@ -807,7 +766,7 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 	
 	mesgsys->getU64Fast(_PREHASH_XferID, _PREHASH_ID, id);
 	char U64_BUF[MAX_STRING];		/* Flawfinder : ignore */
-	LL_INFOS() << "xfer request id: " << U64_to_str(id, U64_BUF, sizeof(U64_BUF))
+	LL_INFOS("Xfer") << "xfer request id: " << U64_to_str(id, U64_BUF, sizeof(U64_BUF))
 		   << " to " << mesgsys->getSender() << LL_ENDL;
 
 	mesgsys->getStringFast(_PREHASH_XferID, _PREHASH_Filename, local_filename);
@@ -825,36 +784,45 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 	LLXfer *xferp;
 
 	if (uuid != LLUUID::null)
-	{
+	{	// Request for an asset - use a VFS file
 		if(NULL == LLAssetType::lookup(type))
 		{
-			LL_WARNS() << "Invalid type for xfer request: " << uuid << ":"
+			LL_WARNS("Xfer") << "Invalid type for xfer request: " << uuid << ":"
 					<< type_s16 << " to " << mesgsys->getSender() << LL_ENDL;
 			return;
 		}
 			
-		LL_INFOS() << "starting vfile transfer: " << uuid << "," << LLAssetType::lookup(type) << " to " << mesgsys->getSender() << LL_ENDL;
-
 		if (! mVFS)
 		{
-			LL_WARNS() << "Attempt to send VFile w/o available VFS" << LL_ENDL;
+			LL_WARNS("Xfer") << "Attempt to send VFile w/o available VFS" << LL_ENDL;
 			return;
 		}
 
+		/* Present in fireengine, not used by viewer
+		if (!validateVFileForTransfer(uuid.asString()))
+		{
+			// it is up to the app sending the file to mark it for expected 
+			// transfer before the request arrives or it will be dropped
+			LL_WARNS("Xfer") << "SECURITY: Unapproved VFile '" << uuid << "'" << LL_ENDL;
+			return;
+		}
+		*/
+
+		LL_INFOS("Xfer") << "starting vfile transfer: " << uuid << "," << LLAssetType::lookup(type) << " to " << mesgsys->getSender() << LL_ENDL;
+
 		xferp = (LLXfer *)new LLXfer_VFile(mVFS, uuid, type);
 		if (xferp)
 		{
-			xferp->mNext = mSendList;
-			mSendList = xferp;	
+			mSendList.push_front(xferp);
 			result = xferp->startSend(id,mesgsys->getSender());
 		}
 		else
 		{
-			LL_ERRS() << "Xfer allcoation error" << LL_ENDL;
+			LL_ERRS("Xfer") << "Xfer allcoation error" << LL_ENDL;
 		}
 	}
 	else if (!local_filename.empty())
-	{
+	{	// Was given a file name to send
 		// See DEV-21775 for detailed security issues
 
 		if (local_path == LL_PATH_NONE)
@@ -873,7 +841,7 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 			case LL_PATH_NONE:
 				if(!validateFileForTransfer(local_filename))
 				{
-					LL_WARNS() << "SECURITY: Unapproved filename '" << local_filename << LL_ENDL;
+					LL_WARNS("Xfer") << "SECURITY: Unapproved filename '" << local_filename << LL_ENDL;
 					return;
 				}
 				break;
@@ -881,13 +849,13 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 			case LL_PATH_CACHE:
 				if(!verify_cache_filename(local_filename))
 				{
-					LL_WARNS() << "SECURITY: Illegal cache filename '" << local_filename << LL_ENDL;
+					LL_WARNS("Xfer") << "SECURITY: Illegal cache filename '" << local_filename << LL_ENDL;
 					return;
 				}
 				break;
 
 			default:
-				LL_WARNS() << "SECURITY: Restricted file dir enum: " << (U32)local_path << LL_ENDL;
+				LL_WARNS("Xfer") << "SECURITY: Restricted file dir enum: " << (U32)local_path << LL_ENDL;
 				return;
 		}
 
@@ -902,7 +870,7 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 		{
 			expanded_filename = local_filename;
 		}
-		LL_INFOS() << "starting file transfer: " <<  expanded_filename << " to " << mesgsys->getSender() << LL_ENDL;
+		LL_INFOS("Xfer") << "starting file transfer: " <<  expanded_filename << " to " << mesgsys->getSender() << LL_ENDL;
 
 		BOOL delete_local_on_completion = FALSE;
 		mesgsys->getBOOL("XferID", "DeleteOnCompletion", delete_local_on_completion);
@@ -912,23 +880,22 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 		
 		if (xferp)
 		{
-			xferp->mNext = mSendList;
-			mSendList = xferp;	
+			mSendList.push_front(xferp);
 			result = xferp->startSend(id,mesgsys->getSender());
 		}
 		else
 		{
-			LL_ERRS() << "Xfer allcoation error" << LL_ENDL;
+			LL_ERRS("Xfer") << "Xfer allcoation error" << LL_ENDL;
 		}
 	}
 	else
-	{
+	{	// no uuid or filename - use the ID sent
 		char U64_BUF[MAX_STRING];		/* Flawfinder : ignore */
-		LL_INFOS() << "starting memory transfer: "
+		LL_INFOS("Xfer") << "starting memory transfer: "
 			<< U64_to_str(id, U64_BUF, sizeof(U64_BUF)) << " to "
 			<< mesgsys->getSender() << LL_ENDL;
 
-		xferp = findXfer(id, mSendList);
+		xferp = findXferByID(id, mSendList);
 		
 		if (xferp)
 		{
@@ -936,7 +903,7 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 		}
 		else
 		{
-			LL_INFOS() << "Warning: " << U64_BUF << " not found." << LL_ENDL;
+			LL_INFOS("Xfer") << "Warning: xfer ID " << U64_BUF << " not found." << LL_ENDL;
 			result = LL_ERR_FILE_NOT_FOUND;
 		}
 	}
@@ -946,11 +913,11 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 		if (xferp)
 		{
 			xferp->abort(result);
-			removeXfer(xferp,&mSendList);
+			removeXfer(xferp, mSendList);
 		}
 		else // can happen with a memory transfer not found
 		{
-			LL_INFOS() << "Aborting xfer to " << mesgsys->getSender() << " with error: " << result << LL_ENDL;
+			LL_INFOS("Xfer") << "Aborting xfer to " << mesgsys->getSender() << " with error: " << result << LL_ENDL;
 
 			mesgsys->newMessageFast(_PREHASH_AbortXfer);
 			mesgsys->nextBlockFast(_PREHASH_XferID);
@@ -960,24 +927,86 @@ void LLXferManager::processFileRequest (LLMessageSystem *mesgsys, void ** /*user
 			mesgsys->sendMessage(mesgsys->getSender());		
 		}
 	}
-	else if(xferp && (numActiveXfers(xferp->mRemoteHost) < mMaxOutgoingXfersPerCircuit))
+	else if(xferp)
 	{
-		xferp->sendNextPacket();
-		changeNumActiveXfers(xferp->mRemoteHost,1);
-//		LL_INFOS() << "***STARTING XFER IMMEDIATELY***" << LL_ENDL;
-	}
-	else
-	{
-		if(xferp)
+		// Figure out how many transfers the host has requested
+		LLHostStatus *host_statusp = findHostStatus(xferp->mRemoteHost);
+		if (host_statusp)
 		{
-			LL_INFOS() << "  queueing xfer request, " << numPendingXfers(xferp->mRemoteHost) << " ahead of this one" << LL_ENDL;
+			if (host_statusp->mNumActive < mMaxOutgoingXfersPerCircuit)
+			{	// Not many transfers in progress already, so start immediately
+				xferp->sendNextPacket();
+				changeNumActiveXfers(xferp->mRemoteHost,1);
+				LL_DEBUGS("Xfer") << "Starting xfer ID " << U64_to_str(id) << " immediately" << LL_ENDL;
+			}
+			else if (mHardLimitOutgoingXfersPerCircuit == 0 ||
+				     (host_statusp->mNumActive + host_statusp->mNumPending) < mHardLimitOutgoingXfersPerCircuit)
+			{	// Must close the file handle and wait for earlier ones to complete
+				LL_INFOS("Xfer") << "  queueing xfer request id " << U64_to_str(id) << ", " 
+								 << host_statusp->mNumActive << " active and "
+								 << host_statusp->mNumPending << " pending ahead of this one" 
+								 << LL_ENDL;
+				xferp->closeFileHandle();	// Close the file handle until we're ready to send again
+			}
+			else if (mHardLimitOutgoingXfersPerCircuit > 0)
+			{	// Way too many requested ... it's time to stop being nice and kill the circuit
+				xferp->closeFileHandle();	// Close the file handle in any case
+				LLCircuitData *cdp = gMessageSystem->mCircuitInfo.findCircuit(xferp->mRemoteHost);
+				if (cdp)
+				{
+					if (cdp->getTrusted())
+					{	// Trusted internal circuit - don't kill it
+						LL_WARNS("Xfer") << "Trusted circuit to " << xferp->mRemoteHost << " has too many xfer requests in the queue " 
+										<< host_statusp->mNumActive << " active and "
+										<< host_statusp->mNumPending << " pending ahead of this one" 
+										<< LL_ENDL;
+					}
+					else
+					{	// Untrusted circuit - time to stop messing around and kill it
+						LL_WARNS("Xfer") << "Killing circuit to " << xferp->mRemoteHost << " for having too many xfer requests in the queue " 
+										<< host_statusp->mNumActive << " active and "
+										<< host_statusp->mNumPending << " pending ahead of this one" 
+										<< LL_ENDL;
+						gMessageSystem->disableCircuit(xferp->mRemoteHost);
+					}
+				}
+				else
+				{	// WTF?   Why can't we find a circuit?  Try to kill it off
+					LL_WARNS("Xfer") << "Backlog with circuit to " << xferp->mRemoteHost << " with too many xfer requests in the queue " 
+									<< host_statusp->mNumActive << " active and "
+									<< host_statusp->mNumPending << " pending ahead of this one" 
+									<< " but no LLCircuitData found???"
+									<< LL_ENDL;
+					gMessageSystem->disableCircuit(xferp->mRemoteHost);
+				}
+			}
 		}
 		else
 		{
-			LL_WARNS() << "LLXferManager::processFileRequest() - no xfer found!"
-					<< LL_ENDL;
+			LL_WARNS("Xfer") << "LLXferManager::processFileRequest() - no LLHostStatus found for id " << U64_to_str(id)	
+				<< " host " << xferp->mRemoteHost << LL_ENDL;
 		}
 	}
+	else
+	{
+		LL_WARNS("Xfer") << "LLXferManager::processFileRequest() - no xfer found for id " << U64_to_str(id)	<< LL_ENDL;
+	}
+}
+ 
+///////////////////////////////////////////////////////////
+
+// Return true if host is in a transfer-flood sitation.  Same check for both internal and external hosts
+bool LLXferManager::isHostFlooded(const LLHost & host)
+{
+	bool flooded = false;
+	LLHostStatus *host_statusp = findHostStatus(host);
+	if (host_statusp)
+	{
+		flooded = (mHardLimitOutgoingXfersPerCircuit > 0 &&
+				    (host_statusp->mNumActive + host_statusp->mNumPending) >= (S32)(mHardLimitOutgoingXfersPerCircuit * 0.8f));
+	}
+
+	return flooded;
 }
 
 
@@ -991,7 +1020,7 @@ void LLXferManager::processConfirmation (LLMessageSystem *mesgsys, void ** /*use
 	mesgsys->getU64Fast(_PREHASH_XferID, _PREHASH_ID, id);
 	mesgsys->getS32Fast(_PREHASH_XferID, _PREHASH_Packet, packetNum);
 
-	LLXfer* xferp = findXfer(id, mSendList);
+	LLXfer* xferp = findXferByID(id, mSendList);
 	if (xferp)
 	{
 //		cout << "confirmed packet #" << packetNum << " ping: "<< xferp->ACKTimer.getElapsedTimeF32() <<  endl;
@@ -1002,91 +1031,105 @@ void LLXferManager::processConfirmation (LLMessageSystem *mesgsys, void ** /*use
 		}
 		else
 		{
-			removeXfer(xferp, &mSendList);
+			removeXfer(xferp, mSendList);
 		}
 	}
 }
 
 ///////////////////////////////////////////////////////////
 
-void LLXferManager::retransmitUnackedPackets ()
+// Called from LLMessageSystem::processAcks()
+void LLXferManager::retransmitUnackedPackets()
 {
 	LLXfer *xferp;
-	LLXfer *delp;
-	xferp = mReceiveList;
-	while(xferp)
+
+	xfer_list_t::iterator iter = mReceiveList.begin();
+	while (iter != mReceiveList.end())
 	{
+		xferp = (*iter);
 		if (xferp->mStatus == e_LL_XFER_IN_PROGRESS)
 		{
 			// if the circuit dies, abort
 			if (! gMessageSystem->mCircuitInfo.isCircuitAlive( xferp->mRemoteHost ))
 			{
-				LL_INFOS() << "Xfer found in progress on dead circuit, aborting" << LL_ENDL;
+				LL_WARNS("Xfer") << "Xfer found in progress on dead circuit, aborting transfer to " 
+					<< xferp->mRemoteHost.getIPandPort()
+					<< LL_ENDL;
 				xferp->mCallbackResult = LL_ERR_CIRCUIT_GONE;
 				xferp->processEOF();
-				delp = xferp;
-				xferp = xferp->mNext;
-				removeXfer(delp,&mReceiveList);
+
+				iter = mReceiveList.erase(iter);	// iter is set to next one after the deletion point
+				delete (xferp);
 				continue;
  			}
 				
 		}
-		xferp = xferp->mNext;
+		++iter;
 	}
 
-	xferp = mSendList; 
+	// Re-build mOutgoingHosts data
 	updateHostStatus();
+
 	F32 et;
-	while (xferp)
+	iter = mSendList.begin();
+	while (iter != mSendList.end())
 	{
+		xferp = (*iter);
 		if (xferp->mWaitingForACK && ( (et = xferp->ACKTimer.getElapsedTimeF32()) > LL_PACKET_TIMEOUT))
 		{
 			if (xferp->mRetries > LL_PACKET_RETRY_LIMIT)
 			{
-				LL_INFOS() << "dropping xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet retransmit limit exceeded, xfer dropped" << LL_ENDL;
+				LL_INFOS("Xfer") << "dropping xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet retransmit limit exceeded, xfer dropped" << LL_ENDL;
 				xferp->abort(LL_ERR_TCP_TIMEOUT);
-				delp = xferp;
-				xferp = xferp->mNext;
-				removeXfer(delp,&mSendList);
+				iter = mSendList.erase(iter);
+				delete xferp;
+				continue;
 			}
 			else
 			{
-				LL_INFOS() << "resending xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet unconfirmed after: "<< et << " sec, packet " << xferp->mPacketNum << LL_ENDL;
+				LL_INFOS("Xfer") << "resending xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << " packet unconfirmed after: "<< et << " sec, packet " << xferp->mPacketNum << LL_ENDL;
 				xferp->resendLastPacket();
-				xferp = xferp->mNext;
 			}
 		}
 		else if ((xferp->mStatus == e_LL_XFER_REGISTERED) && ( (et = xferp->ACKTimer.getElapsedTimeF32()) > LL_XFER_REGISTRATION_TIMEOUT))
 		{
-			LL_INFOS() << "registered xfer never requested, xfer dropped" << LL_ENDL;
+			LL_INFOS("Xfer") << "registered xfer never requested, xfer dropped" << LL_ENDL;
 			xferp->abort(LL_ERR_TCP_TIMEOUT);
-			delp = xferp;
-			xferp = xferp->mNext;
-			removeXfer(delp,&mSendList);
+			iter = mSendList.erase(iter);
+			delete xferp;
+			continue;
 		}
 		else if (xferp->mStatus == e_LL_XFER_ABORTED)
 		{
-			LL_WARNS() << "Removing aborted xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << LL_ENDL;
-			delp = xferp;
-			xferp = xferp->mNext;
-			removeXfer(delp,&mSendList);
+			LL_WARNS("Xfer") << "Removing aborted xfer " << xferp->mRemoteHost << ":" << xferp->getFileName() << LL_ENDL;
+			iter = mSendList.erase(iter);
+			delete xferp;
+			continue;
 		}
 		else if (xferp->mStatus == e_LL_XFER_PENDING)
 		{
-//			LL_INFOS() << "*** numActiveXfers = " << numActiveXfers(xferp->mRemoteHost) << "        mMaxOutgoingXfersPerCircuit = " << mMaxOutgoingXfersPerCircuit << LL_ENDL;   
+//			LL_INFOS("Xfer") << "*** numActiveXfers = " << numActiveXfers(xferp->mRemoteHost) << "        mMaxOutgoingXfersPerCircuit = " << mMaxOutgoingXfersPerCircuit << LL_ENDL;   
 			if (numActiveXfers(xferp->mRemoteHost) < mMaxOutgoingXfersPerCircuit)
 			{
-//			    LL_INFOS() << "bumping pending xfer to active" << LL_ENDL;
-				xferp->sendNextPacket();
-				changeNumActiveXfers(xferp->mRemoteHost,1);
-			}			
-			xferp = xferp->mNext;
-		}
-		else
-		{
-			xferp = xferp->mNext;
+				if (xferp->reopenFileHandle())
+				{
+					LL_WARNS("Xfer") << "Error re-opening file handle for xfer ID " << U64_to_str(xferp->mID)
+						<< " to host " << xferp->mRemoteHost << LL_ENDL;
+					xferp->abort(LL_ERR_CANNOT_OPEN_FILE);
+					iter = mSendList.erase(iter);
+					delete xferp;
+					continue;
+				}
+				else
+				{	// No error re-opening the file, send the first packet
+					LL_DEBUGS("Xfer") << "Moving pending xfer ID " << U64_to_str(xferp->mID) << " to active" << LL_ENDL;
+					xferp->sendNextPacket();
+					changeNumActiveXfers(xferp->mRemoteHost,1);
+				}
+			}
 		}
-	}
+		++iter;
+	} // end while() loop
 
 	//
 	// HACK - if we're using xfer confirm throttling, throttle our xfer confirms here
@@ -1099,10 +1142,10 @@ void LLXferManager::retransmitUnackedPackets ()
 		{
 			break;
 		}
-		//LL_INFOS() << "Confirm packet queue length:" << mXferAckQueue.size() << LL_ENDL;
+		//LL_INFOS("Xfer") << "Confirm packet queue length:" << mXferAckQueue.size() << LL_ENDL;
 		LLXferAckInfo ack_info = mXferAckQueue.front();
 		mXferAckQueue.pop_front();
-		//LL_INFOS() << "Sending confirm packet" << LL_ENDL;
+		//LL_INFOS("Xfer") << "Sending confirm packet" << LL_ENDL;
 		sendConfirmPacket(gMessageSystem, ack_info.mID, ack_info.mPacketNum, ack_info.mRemoteHost);
 		mAckThrottle.throttleOverflow(1000.f*8.f); // Assume 1000 bytes/packet
 	}
@@ -1112,7 +1155,7 @@ void LLXferManager::retransmitUnackedPackets ()
 
 void LLXferManager::abortRequestById(U64 xfer_id, S32 result_code)
 {
-	LLXfer * xferp = findXfer(xfer_id, mReceiveList);
+	LLXfer * xferp = findXferByID(xfer_id, mReceiveList);
 	if (xferp)
 	{
 		if (xferp->mStatus == e_LL_XFER_IN_PROGRESS)
@@ -1124,7 +1167,7 @@ void LLXferManager::abortRequestById(U64 xfer_id, S32 result_code)
 		{
 			xferp->mCallbackResult = result_code;
 			xferp->processEOF(); //should notify requester
-			removeXfer(xferp, &mReceiveList);
+			removeXfer(xferp, mReceiveList);
 		}
 		// Since already removed or marked as aborted no need
 		// to wait for processAbort() to start new download
@@ -1143,12 +1186,12 @@ void LLXferManager::processAbort (LLMessageSystem *mesgsys, void ** /*user_data*
 	mesgsys->getU64Fast(_PREHASH_XferID, _PREHASH_ID, id);
 	mesgsys->getS32Fast(_PREHASH_XferID, _PREHASH_Result, result_code);
 
-	xferp = findXfer(id, mReceiveList);
+	xferp = findXferByID(id, mReceiveList);
 	if (xferp)
 	{
 		xferp->mCallbackResult = result_code;
 		xferp->processEOF();
-		removeXfer(xferp, &mReceiveList);
+		removeXfer(xferp, mReceiveList);
 		startPendingDownloads();
 	}
 }
@@ -1164,27 +1207,29 @@ void LLXferManager::startPendingDownloads()
 	// requests get pushed toward the back. Thus, if we didn't do a
 	// stateful iteration, it would be possible for old requests to
 	// never start.
-	LLXfer* xferp = mReceiveList;
+	LLXfer* xferp;
 	std::list<LLXfer*> pending_downloads;
 	S32 download_count = 0;
 	S32 pending_count = 0;
-	while(xferp)
+	for (xfer_list_t::iterator iter = mReceiveList.begin();
+		 iter != mReceiveList.end();
+		 ++iter)
 	{
+		xferp = (*iter);
 		if(xferp->mStatus == e_LL_XFER_PENDING)
-		{
+		{	// Count and accumulate pending downloads
 			++pending_count;
 			pending_downloads.push_front(xferp);
 		}
 		else if(xferp->mStatus == e_LL_XFER_IN_PROGRESS)
-		{
+		{	// Count downloads in progress
 			++download_count;
 		}
-		xferp = xferp->mNext;
 	}
 
 	S32 start_count = mMaxIncomingXfers - download_count;
 
-	LL_DEBUGS() << "LLXferManager::startPendingDownloads() - XFER_IN_PROGRESS: "
+	LL_DEBUGS("Xfer") << "LLXferManager::startPendingDownloads() - XFER_IN_PROGRESS: "
 			 << download_count << " XFER_PENDING: " << pending_count
 			 << " startring " << llmin(start_count, pending_count) << LL_ENDL;
 
@@ -1209,29 +1254,15 @@ void LLXferManager::startPendingDownloads()
 
 ///////////////////////////////////////////////////////////
 
-void LLXferManager::addToList(LLXfer* xferp, LLXfer*& head, BOOL is_priority)
+void LLXferManager::addToList(LLXfer* xferp, xfer_list_t & xfer_list, BOOL is_priority)
 {
 	if(is_priority)
 	{
-		xferp->mNext = NULL;
-		LLXfer* next = head;
-		if(next)
-		{
-			while(next->mNext)
-			{
-				next = next->mNext;
-			}
-			next->mNext = xferp;
-		}
-		else
-		{
-			head = xferp;
-		}
+		xfer_list.push_back(xferp);
 	}
 	else
 	{
-		xferp->mNext = head;
-		head = xferp;
+		xfer_list.push_front(xferp);
 	}
 }
 
diff --git a/indra/llmessage/llxfermanager.h b/indra/llmessage/llxfermanager.h
index d258f0a5ce..45ae2ffdd3 100644
--- a/indra/llmessage/llxfermanager.h
+++ b/indra/llmessage/llxfermanager.h
@@ -77,6 +77,7 @@ class LLXferManager
 
  protected:
 	S32    mMaxOutgoingXfersPerCircuit;
+	S32    mHardLimitOutgoingXfersPerCircuit;	// At this limit, kill off the connection
 	S32    mMaxIncomingXfers;
 
 	BOOL	mUseAckThrottling; // Use ack throttling to cap file xfer bandwidth
@@ -92,19 +93,22 @@ class LLXferManager
 		HIGH_PRIORITY = TRUE,
 	};
 
-	LLXfer *mSendList;
-	LLXfer *mReceiveList;
+	// Linked FIFO list, add to the front and pull from back
+	typedef std::deque<LLXfer *> xfer_list_t;
+	xfer_list_t		mSendList;
+	xfer_list_t		mReceiveList;
 
 	typedef std::list<LLHostStatus*> status_list_t;
 	status_list_t mOutgoingHosts;
 
- private:
  protected:
 	// implementation methods
 	virtual void startPendingDownloads();
-	virtual void addToList(LLXfer* xferp, LLXfer*& head, BOOL is_priority);
+	virtual void addToList(LLXfer* xferp, xfer_list_t & xfer_list, BOOL is_priority);
 	std::multiset<std::string> mExpectedTransfers; // files that are authorized to transfer out
 	std::multiset<std::string> mExpectedRequests;  // files that are authorized to be downloaded on top of
+	std::multiset<std::string> mExpectedVFileTransfers; // files that are authorized to transfer out
+	std::multiset<std::string> mExpectedVFileRequests;  // files that are authorized to be downloaded on top of
 
  public:
 	LLXferManager(LLVFS *vfs);
@@ -117,14 +121,17 @@ class LLXferManager
 	void setAckThrottleBPS(const F32 bps);
 
 // list management routines
-	virtual LLXfer *findXfer(U64 id, LLXfer *list_head);
-	virtual void removeXfer (LLXfer *delp, LLXfer **list_head);
-	virtual U32 numActiveListEntries(LLXfer *list_head);
+	virtual LLXfer *findXferByID(U64 id, xfer_list_t & xfer_list);
+	virtual void removeXfer (LLXfer *delp, xfer_list_t & xfer_list);
+
+	LLHostStatus * findHostStatus(const LLHost &host);
 	virtual S32 numActiveXfers(const LLHost &host);
 	virtual S32 numPendingXfers(const LLHost &host);
+
 	virtual void changeNumActiveXfers(const LLHost &host, S32 delta);
 
 	virtual void setMaxOutgoingXfersPerCircuit (S32 max_num);
+	virtual void setHardLimitOutgoingXfersPerCircuit(S32 max_num);
 	virtual void setMaxIncomingXfers(S32 max_num);
 	virtual void updateHostStatus();
 	virtual void printHostStatus();
@@ -136,8 +143,6 @@ class LLXferManager
 	virtual S32 decodePacketNum(S32 packet_num);	
 	virtual BOOL isLastPacket(S32 packet_num);
 
-	virtual U64 registerXfer(const void *datap, const S32 length);
-
 // file requesting routines
 // .. to file
 	virtual U64 requestFile(const std::string& local_filename,
@@ -148,7 +153,7 @@ class LLXferManager
 							 void (*callback)(void**,S32,LLExtStat), void** user_data,
 							 BOOL is_priority = FALSE,
 							 BOOL use_big_packets = FALSE);
-
+	/*
 // .. to memory
 	virtual void requestFile(const std::string& remote_filename, 
 							 ELLPath remote_path,
@@ -157,7 +162,7 @@ class LLXferManager
 							 void (*callback)(void*, S32, void**, S32, LLExtStat),
 							 void** user_data,
 							 BOOL is_priority = FALSE);
-
+	*/
 // vfile requesting
 // .. to vfile
 	virtual void requestVFile(const LLUUID &local_id, const LLUUID& remote_id,
@@ -180,18 +185,15 @@ class LLXferManager
 	virtual void expectFileForRequest(const std::string& filename);
 	virtual bool validateFileForRequest(const std::string& filename);
 
-/*
-// xfer request (may be memory or file)
-// .. to file
-	virtual void requestXfer(const char *local_filename, U64 xfer_id, 
-							 BOOL delete_remote_on_completion,
-							 const LLHost &remote_host, void (*callback)(void **,S32),void **user_data);
-// .. to memory
-	virtual void requestXfer(U64 xfer_id, 
-							 const LLHost &remote_host, 
-							 BOOL delete_remote_on_completion,
-							 void (*callback)(void *, S32, void **, S32),void **user_data);
-*/
+	/**
+	  	Same idea but for VFiles, kept separate to avoid namespace overlap
+	*/
+	/* Present in fireengine, not used by viewer
+	virtual void expectVFileForTransfer(const std::string& filename);
+	virtual bool validateVFileForTransfer(const std::string& filename);
+	virtual void expectVFileForRequest(const std::string& filename);
+	virtual bool validateVFileForRequest(const std::string& filename);
+	*/
 
 	virtual void processReceiveData (LLMessageSystem *mesgsys, void **user_data);
 	virtual void sendConfirmPacket (LLMessageSystem *mesgsys, U64 id, S32 packetnum, const LLHost &remote_host);
@@ -204,6 +206,8 @@ class LLXferManager
 // error handling
 	void abortRequestById(U64 xfer_id, S32 result_code);
 	virtual void processAbort (LLMessageSystem *mesgsys, void **user_data);
+
+	virtual bool isHostFlooded(const LLHost & host);
 };
 
 extern LLXferManager*	gXferManager;