From 4fc0cfba3ce1e6545e334f8e34a0e5b45274081e Mon Sep 17 00:00:00 2001 From: "Justin Clark-Casey (justincc)" Date: Tue, 25 Sep 2012 21:35:39 +0100 Subject: [PATCH] Fix occasional race condition failure when creating new clothing/body parts in the viewer or updating existing assets. On creating these items, the viewer sends a UDP AssetUploadRequest followed by a CreateInventoryItem. It was possible for the CreateInventoryItem/UpdateInventoryItem to occasionally outrace the AssetUploadRequest and fail to find an initialized Xfer object, at which point the item create would fail. So instead we always set up a Xfer object on either the asset or inventory item update request. This does not introduce a new race because code already exists to delay the item operation until the asset is uploaded if necessary (but this only worked if the xfer object already existed) --- .../AgentAssetsTransactions.cs | 123 ++++++------------ .../AssetTransactionModule.cs | 9 +- .../AssetTransaction/AssetXferUploader.cs | 72 +++++++--- 3 files changed, 94 insertions(+), 110 deletions(-) diff --git a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AgentAssetsTransactions.cs b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AgentAssetsTransactions.cs index b557ffe5f2..bba7b9ca27 100644 --- a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AgentAssetsTransactions.cs +++ b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AgentAssetsTransactions.cs @@ -57,39 +57,36 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction } /// - /// Return a xfer uploader if one does not already exist. + /// Return the xfer uploader for the given transaction. /// + /// + /// If an uploader does not already exist for this transaction then it is created, otherwise the existing + /// uploader is returned. + /// /// - /// - /// We must transfer the new asset ID into the uploader on creation, otherwise - /// we can see race conditions with other threads which can retrieve an item before it is updated with the new - /// asset id. - /// - /// - /// The xfer uploader requested. Null if one is already in existence. - /// FIXME: This is a bizarre thing to do, and is probably meant to signal an error condition if multiple - /// transfers are made. Needs to be corrected. - /// - public AssetXferUploader RequestXferUploader(UUID transactionID, UUID assetID) + /// The asset xfer uploader + public AssetXferUploader RequestXferUploader(UUID transactionID) { + AssetXferUploader uploader; + lock (XferUploaders) { if (!XferUploaders.ContainsKey(transactionID)) { - AssetXferUploader uploader = new AssetXferUploader(this, m_Scene, assetID, m_dumpAssetsToFile); + uploader = new AssetXferUploader(this, m_Scene, m_dumpAssetsToFile); // m_log.DebugFormat( // "[AGENT ASSETS TRANSACTIONS]: Adding asset xfer uploader {0} since it didn't previously exist", transactionID); XferUploaders.Add(transactionID, uploader); - - return uploader; + } + else + { + uploader = XferUploaders[transactionID]; } } - m_log.WarnFormat("[AGENT ASSETS TRANSACTIONS]: Ignoring request for asset xfer uploader {0} since it already exists", transactionID); - - return null; + return uploader; } public void HandleXfer(ulong xferID, uint packetID, byte[] data) @@ -151,23 +148,11 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction string description, string name, sbyte invType, sbyte type, byte wearableType, uint nextOwnerMask) { - AssetXferUploader uploader = null; + AssetXferUploader uploader = RequestXferUploader(transactionID); - lock (XferUploaders) - { - if (XferUploaders.ContainsKey(transactionID)) - uploader = XferUploaders[transactionID]; - } - - if (uploader != null) - uploader.RequestCreateInventoryItem( - remoteClient, transactionID, folderID, - callbackID, description, name, invType, type, - wearableType, nextOwnerMask); - else - m_log.ErrorFormat( - "[AGENT ASSET TRANSACTIONS]: Could not find uploader with transaction ID {0} when handling request to create inventory item {1} from {2}", - transactionID, name, remoteClient.Name); + uploader.RequestCreateInventoryItem( + remoteClient, transactionID, folderID, callbackID, + description, name, invType, type, wearableType, nextOwnerMask); } /// @@ -197,69 +182,37 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction SceneObjectPart part, UUID transactionID, TaskInventoryItem item) { - AssetXferUploader uploader = null; + AssetBase asset = GetTransactionAsset(transactionID); - lock (XferUploaders) + // Only legacy viewers use this, and they prefer CAPS, which + // we have, so this really never runs. + // Allow it, but only for "safe" types. + if ((InventoryType)item.InvType != InventoryType.Notecard && + (InventoryType)item.InvType != InventoryType.LSL) + return; + + if (asset != null) { - if (XferUploaders.ContainsKey(transactionID)) - uploader = XferUploaders[transactionID]; - } - - if (uploader != null) - { - AssetBase asset = GetTransactionAsset(transactionID); - - // Only legacy viewers use this, and they prefer CAPS, which - // we have, so this really never runs. - // Allow it, but only for "safe" types. - if ((InventoryType)item.InvType != InventoryType.Notecard && - (InventoryType)item.InvType != InventoryType.LSL) - return; - - if (asset != null) - { // m_log.DebugFormat( // "[AGENT ASSETS TRANSACTIONS]: Updating item {0} in {1} for transaction {2}", // item.Name, part.Name, transactionID); - - asset.FullID = UUID.Random(); - asset.Name = item.Name; - asset.Description = item.Description; - asset.Type = (sbyte)item.Type; - item.AssetID = asset.FullID; + + asset.FullID = UUID.Random(); + asset.Name = item.Name; + asset.Description = item.Description; + asset.Type = (sbyte)item.Type; + item.AssetID = asset.FullID; - m_Scene.AssetService.Store(asset); - } - } - else - { - m_log.ErrorFormat( - "[AGENT ASSET TRANSACTIONS]: Could not find uploader with transaction ID {0} when handling request to update task inventory item {1} in {2}", - transactionID, item.Name, part.Name); + m_Scene.AssetService.Store(asset); } } public void RequestUpdateInventoryItem(IClientAPI remoteClient, UUID transactionID, InventoryItemBase item) { - AssetXferUploader uploader = null; + AssetXferUploader uploader = RequestXferUploader(transactionID); - lock (XferUploaders) - { - if (XferUploaders.ContainsKey(transactionID)) - uploader = XferUploaders[transactionID]; - } - - if (uploader != null) - { - uploader.RequestUpdateInventoryItem(remoteClient, transactionID, item); - } - else - { - m_log.ErrorFormat( - "[AGENT ASSET TRANSACTIONS]: Could not find uploader with transaction ID {0} when handling request to update inventory item {1} for {2}", - transactionID, item.Name, remoteClient.Name); - } + uploader.RequestUpdateInventoryItem(remoteClient, transactionID, item); } } -} +} \ No newline at end of file diff --git a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetTransactionModule.cs b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetTransactionModule.cs index 708198923a..10a0794c23 100644 --- a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetTransactionModule.cs +++ b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetTransactionModule.cs @@ -274,13 +274,8 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction } AgentAssetTransactions transactions = GetUserTransactions(remoteClient.AgentId); - AssetXferUploader uploader = transactions.RequestXferUploader(transaction, assetID); - - if (uploader != null) - { - uploader.Initialise(remoteClient, assetID, transaction, type, - data, storeLocal, tempFile); - } + AssetXferUploader uploader = transactions.RequestXferUploader(transaction); + uploader.StartUpload(remoteClient, assetID, transaction, type, data, storeLocal, tempFile); } /// diff --git a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetXferUploader.cs b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetXferUploader.cs index ec4dfd0bbb..9f05120798 100644 --- a/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetXferUploader.cs +++ b/OpenSim/Region/CoreModules/Agent/AssetTransaction/AssetXferUploader.cs @@ -40,12 +40,27 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction { private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); + /// + /// Upload state. + /// + /// + /// New -> Uploading -> Complete + /// + private enum UploadState + { + New, + Uploading, + Complete + } + /// /// Reference to the object that holds this uploader. Used to remove ourselves from it's list if we /// are performing a delayed update. /// AgentAssetTransactions m_transactions; + private UploadState m_uploadState = UploadState.New; + private AssetBase m_asset; private UUID InventFolder = UUID.Zero; private sbyte invType = 0; @@ -57,7 +72,6 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction private string m_description = String.Empty; private bool m_dumpAssetToFile; - private bool m_finished = false; private string m_name = String.Empty; private bool m_storeLocal; private uint nextPerm = 0; @@ -68,11 +82,10 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction public ulong XferID; private Scene m_Scene; - public AssetXferUploader(AgentAssetTransactions transactions, Scene scene, UUID assetID, bool dumpAssetToFile) + public AssetXferUploader(AgentAssetTransactions transactions, Scene scene, bool dumpAssetToFile) { m_transactions = transactions; m_Scene = scene; - m_asset = new AssetBase() { FullID = assetID }; m_dumpAssetToFile = dumpAssetToFile; } @@ -118,20 +131,43 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction } /// - /// Initialise asset transfer from the client + /// Start asset transfer from the client /// - /// - /// - /// - public void Initialise(IClientAPI remoteClient, UUID assetID, - UUID transaction, sbyte type, byte[] data, bool storeLocal, - bool tempFile) + /// + /// + /// + /// + /// + /// Optional data. If present then the asset is created immediately with this data + /// rather than requesting an upload from the client. The data must be longer than 2 bytes. + /// + /// + /// + public void StartUpload( + IClientAPI remoteClient, UUID assetID, UUID transaction, sbyte type, byte[] data, bool storeLocal, + bool tempFile) { // m_log.DebugFormat( // "[ASSET XFER UPLOADER]: Initialised xfer from {0}, asset {1}, transaction {2}, type {3}, storeLocal {4}, tempFile {5}, already received data length {6}", // remoteClient.Name, assetID, transaction, type, storeLocal, tempFile, data.Length); + lock (this) + { + if (m_uploadState != UploadState.New) + { + m_log.WarnFormat( + "[ASSET XFER UPLOADER]: Tried to start upload of asset {0}, transaction {1} for {2} but this is already in state {3}. Aborting.", + assetID, transaction, remoteClient.Name, m_uploadState); + + return; + } + + m_uploadState = UploadState.Uploading; + } + ourClient = remoteClient; + + m_asset = new AssetBase() { FullID = assetID }; m_asset.Name = "blank"; m_asset.Description = "empty"; m_asset.Type = type; @@ -166,14 +202,14 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction protected void SendCompleteMessage() { - ourClient.SendAssetUploadCompleteMessage(m_asset.Type, true, - m_asset.FullID); - // We must lock in order to avoid a race with a separate thread dealing with an inventory item or create // message from other client UDP. lock (this) { - m_finished = true; + m_uploadState = UploadState.Complete; + + ourClient.SendAssetUploadCompleteMessage(m_asset.Type, true, m_asset.FullID); + if (m_createItem) { DoCreateItem(m_createItemCallback); @@ -243,7 +279,7 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction // We must lock to avoid a race with a separate thread uploading the asset. lock (this) { - if (m_finished) + if (m_uploadState == UploadState.Complete) { DoCreateItem(callbackID); } @@ -271,7 +307,7 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction item.AssetID = m_asset.FullID; m_Scene.InventoryService.UpdateItem(item); - if (m_finished) + if (m_uploadState == UploadState.Complete) { StoreAssetForItemUpdate(item); } @@ -334,7 +370,7 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction /// null if the asset has not finished uploading public AssetBase GetAssetData() { - if (m_finished) + if (m_uploadState == UploadState.Complete) { return m_asset; } @@ -342,4 +378,4 @@ namespace OpenSim.Region.CoreModules.Agent.AssetTransaction return null; } } -} +} \ No newline at end of file