michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 et sw=2 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_dom_indexeddb_transactionthreadpool_h__
michael@0: #define mozilla_dom_indexeddb_transactionthreadpool_h__
michael@0: 
michael@0: // Only meant to be included in IndexedDB source files, not exported.
michael@0: #include "IndexedDatabase.h"
michael@0: 
michael@0: #include "nsIObserver.h"
michael@0: #include "nsIRunnable.h"
michael@0: 
michael@0: #include "mozilla/Monitor.h"
michael@0: #include "nsClassHashtable.h"
michael@0: #include "nsHashKeys.h"
michael@0: 
michael@0: #include "IDBTransaction.h"
michael@0: 
michael@0: class nsIThreadPool;
michael@0: 
michael@0: BEGIN_INDEXEDDB_NAMESPACE
michael@0: 
michael@0: class FinishTransactionRunnable;
michael@0: class QueuedDispatchInfo;
michael@0: 
michael@0: class TransactionThreadPool
michael@0: {
michael@0:   friend class nsAutoPtr<TransactionThreadPool>;
michael@0:   friend class FinishTransactionRunnable;
michael@0: 
michael@0: public:
michael@0:   // returns a non-owning ref!
michael@0:   static TransactionThreadPool* GetOrCreate();
michael@0: 
michael@0:   // returns a non-owning ref!
michael@0:   static TransactionThreadPool* Get();
michael@0: 
michael@0:   static void Shutdown();
michael@0: 
michael@0:   nsresult Dispatch(IDBTransaction* aTransaction,
michael@0:                     nsIRunnable* aRunnable,
michael@0:                     bool aFinish,
michael@0:                     nsIRunnable* aFinishRunnable);
michael@0: 
michael@0:   void WaitForDatabasesToComplete(nsTArray<nsRefPtr<IDBDatabase> >& aDatabases,
michael@0:                                   nsIRunnable* aCallback);
michael@0: 
michael@0:   // Abort all transactions, unless they are already in the process of being
michael@0:   // committed, for aDatabase.
michael@0:   void AbortTransactionsForDatabase(IDBDatabase* aDatabase);
michael@0: 
michael@0:   // Returns true if there are running or pending transactions for aDatabase.
michael@0:   bool HasTransactionsForDatabase(IDBDatabase* aDatabase);
michael@0: 
michael@0: protected:
michael@0:   class TransactionQueue MOZ_FINAL : public nsIRunnable
michael@0:   {
michael@0:   public:
michael@0:     NS_DECL_THREADSAFE_ISUPPORTS
michael@0:     NS_DECL_NSIRUNNABLE
michael@0: 
michael@0:     TransactionQueue(IDBTransaction* aTransaction);
michael@0: 
michael@0:     void Unblock();
michael@0: 
michael@0:     void Dispatch(nsIRunnable* aRunnable);
michael@0: 
michael@0:     void Finish(nsIRunnable* aFinishRunnable);
michael@0: 
michael@0:   private:
michael@0:     mozilla::Monitor mMonitor;
michael@0:     IDBTransaction* mTransaction;
michael@0:     nsAutoTArray<nsCOMPtr<nsIRunnable>, 10> mQueue;
michael@0:     nsCOMPtr<nsIRunnable> mFinishRunnable;
michael@0:     bool mShouldFinish;
michael@0:   };
michael@0: 
michael@0:   friend class TransactionQueue;
michael@0: 
michael@0:   struct TransactionInfo
michael@0:   {
michael@0:     TransactionInfo(IDBTransaction* aTransaction)
michael@0:     {
michael@0:       MOZ_COUNT_CTOR(TransactionInfo);
michael@0: 
michael@0:       transaction = aTransaction;
michael@0:       queue = new TransactionQueue(aTransaction);
michael@0:     }
michael@0: 
michael@0:     ~TransactionInfo()
michael@0:     {
michael@0:       MOZ_COUNT_DTOR(TransactionInfo);
michael@0:     }
michael@0: 
michael@0:     nsRefPtr<IDBTransaction> transaction;
michael@0:     nsRefPtr<TransactionQueue> queue;
michael@0:     nsTHashtable<nsPtrHashKey<TransactionInfo> > blockedOn;
michael@0:     nsTHashtable<nsPtrHashKey<TransactionInfo> > blocking;
michael@0:   };
michael@0: 
michael@0:   struct TransactionInfoPair
michael@0:   {
michael@0:     TransactionInfoPair()
michael@0:       : lastBlockingReads(nullptr)
michael@0:     {
michael@0:       MOZ_COUNT_CTOR(TransactionInfoPair);
michael@0:     }
michael@0: 
michael@0:     ~TransactionInfoPair()
michael@0:     {
michael@0:       MOZ_COUNT_DTOR(TransactionInfoPair);
michael@0:     }
michael@0:     // Multiple reading transactions can block future writes.
michael@0:     nsTArray<TransactionInfo*> lastBlockingWrites;
michael@0:     // But only a single writing transaction can block future reads.
michael@0:     TransactionInfo* lastBlockingReads;
michael@0:   };
michael@0: 
michael@0:   struct DatabaseTransactionInfo
michael@0:   {
michael@0:     DatabaseTransactionInfo()
michael@0:     {
michael@0:       MOZ_COUNT_CTOR(DatabaseTransactionInfo);
michael@0:     }
michael@0: 
michael@0:     ~DatabaseTransactionInfo()
michael@0:     {
michael@0:       MOZ_COUNT_DTOR(DatabaseTransactionInfo);
michael@0:     }
michael@0: 
michael@0:     typedef nsClassHashtable<nsPtrHashKey<IDBTransaction>, TransactionInfo >
michael@0:       TransactionHashtable;
michael@0:     TransactionHashtable transactions;
michael@0:     nsClassHashtable<nsStringHashKey, TransactionInfoPair> blockingTransactions;
michael@0:   };
michael@0: 
michael@0:   static PLDHashOperator
michael@0:   CollectTransactions(IDBTransaction* aKey,
michael@0:                       TransactionInfo* aValue,
michael@0:                       void* aUserArg);
michael@0: 
michael@0:   static PLDHashOperator
michael@0:   FindTransaction(IDBTransaction* aKey,
michael@0:                   TransactionInfo* aValue,
michael@0:                   void* aUserArg);
michael@0: 
michael@0:   static PLDHashOperator
michael@0:   MaybeUnblockTransaction(nsPtrHashKey<TransactionInfo>* aKey,
michael@0:                           void* aUserArg);
michael@0: 
michael@0:   struct DatabasesCompleteCallback
michael@0:   {
michael@0:     nsTArray<nsRefPtr<IDBDatabase> > mDatabases;
michael@0:     nsCOMPtr<nsIRunnable> mCallback;
michael@0:   };
michael@0: 
michael@0:   TransactionThreadPool();
michael@0:   ~TransactionThreadPool();
michael@0: 
michael@0:   nsresult Init();
michael@0:   nsresult Cleanup();
michael@0: 
michael@0:   void FinishTransaction(IDBTransaction* aTransaction);
michael@0: 
michael@0:   TransactionQueue& GetQueueForTransaction(IDBTransaction* aTransaction);
michael@0: 
michael@0:   bool MaybeFireCallback(DatabasesCompleteCallback aCallback);
michael@0: 
michael@0:   nsCOMPtr<nsIThreadPool> mThreadPool;
michael@0: 
michael@0:   nsClassHashtable<nsCStringHashKey, DatabaseTransactionInfo>
michael@0:     mTransactionsInProgress;
michael@0: 
michael@0:   nsTArray<DatabasesCompleteCallback> mCompleteCallbacks;
michael@0: };
michael@0: 
michael@0: END_INDEXEDDB_NAMESPACE
michael@0: 
michael@0: #endif // mozilla_dom_indexeddb_transactionthreadpool_h__