code.vuplus.com Git - vuplus_webkit/blob - Source/WebCore/storage/SQLTransactionCoordinator.cpp

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   3  *
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   6  * met:
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   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
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  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  29  */
  30
  31 #include "config.h"
  32 #include "SQLTransactionCoordinator.h"
  33
  34 #if ENABLE(DATABASE)
  35
  36 #include "Database.h"
  37 #include "SQLTransaction.h"
  38 #include <wtf/Deque.h>
  39 #include <wtf/HashMap.h>
  40 #include <wtf/HashSet.h>
  41 #include <wtf/RefPtr.h>
  42
  43 namespace WebCore {
  44
  45 static String getDatabaseIdentifier(SQLTransaction* transaction)
  46 {
  47     Database* database = transaction->database();
  48     ASSERT(database);
  49     return database->stringIdentifier();
  50 }
  51
  52 void SQLTransactionCoordinator::processPendingTransactions(CoordinationInfo& info)
  53 {
  54     if (info.activeWriteTransaction || info.pendingTransactions.isEmpty())
  55         return;
  56
  57     RefPtr<SQLTransaction> firstPendingTransaction = info.pendingTransactions.first();
  58     if (firstPendingTransaction->isReadOnly()) {
  59         do {
  60             firstPendingTransaction = info.pendingTransactions.takeFirst();
  61             info.activeReadTransactions.add(firstPendingTransaction);
  62             firstPendingTransaction->lockAcquired();
  63         } while (!info.pendingTransactions.isEmpty() && info.pendingTransactions.first()->isReadOnly());
  64     } else if (info.activeReadTransactions.isEmpty()) {
  65         info.pendingTransactions.removeFirst();
  66         info.activeWriteTransaction = firstPendingTransaction;
  67         firstPendingTransaction->lockAcquired();
  68     }
  69 }
  70
  71 void SQLTransactionCoordinator::acquireLock(SQLTransaction* transaction)
  72 {
  73     String dbIdentifier = getDatabaseIdentifier(transaction);
  74
  75     CoordinationInfoMap::iterator coordinationInfoIterator = m_coordinationInfoMap.find(dbIdentifier);
  76     if (coordinationInfoIterator == m_coordinationInfoMap.end()) {
  77         // No pending transactions for this DB
  78         coordinationInfoIterator = m_coordinationInfoMap.add(dbIdentifier, CoordinationInfo()).first;
  79     }
  80
  81     CoordinationInfo& info = coordinationInfoIterator->second;
  82     info.pendingTransactions.append(transaction);
  83     processPendingTransactions(info);
  84 }
  85
  86 void SQLTransactionCoordinator::releaseLock(SQLTransaction* transaction)
  87 {
  88     if (m_coordinationInfoMap.isEmpty())
  89         return;
  90
  91     String dbIdentifier = getDatabaseIdentifier(transaction);
  92
  93     CoordinationInfoMap::iterator coordinationInfoIterator = m_coordinationInfoMap.find(dbIdentifier);
  94     ASSERT(coordinationInfoIterator != m_coordinationInfoMap.end());
  95     CoordinationInfo& info = coordinationInfoIterator->second;
  96
  97     if (transaction->isReadOnly()) {
  98         ASSERT(info.activeReadTransactions.contains(transaction));
  99         info.activeReadTransactions.remove(transaction);
 100     } else {
 101         ASSERT(info.activeWriteTransaction == transaction);
 102         info.activeWriteTransaction = 0;
 103     }
 104
 105     processPendingTransactions(info);
 106 }
 107
 108 void SQLTransactionCoordinator::shutdown()
 109 {
 110     // Notify all transactions in progress that the database thread is shutting down
 111     for (CoordinationInfoMap::iterator coordinationInfoIterator = m_coordinationInfoMap.begin();
 112          coordinationInfoIterator != m_coordinationInfoMap.end(); ++coordinationInfoIterator) {
 113         CoordinationInfo& info = coordinationInfoIterator->second;
 114         if (info.activeWriteTransaction)
 115             info.activeWriteTransaction->notifyDatabaseThreadIsShuttingDown();
 116         for (HashSet<RefPtr<SQLTransaction> >::iterator activeReadTransactionsIterator =
 117                      info.activeReadTransactions.begin();
 118              activeReadTransactionsIterator != info.activeReadTransactions.end();
 119              ++activeReadTransactionsIterator) {
 120             (*activeReadTransactionsIterator)->notifyDatabaseThreadIsShuttingDown();
 121         }
 122     }
 123
 124     // Clean up all pending transactions for all databases
 125     m_coordinationInfoMap.clear();
 126 }
 127
 128 } // namespace WebCore
 129
 130 #endif // ENABLE(DATABASE)