Source/WebCore/platform/sql/SQLiteDatabaseTracker.cpp

   1 /*
   2  * Copyright (C) 2010, 2012 Apple Inc. All Rights Reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "config.h"
  27 #include "SQLiteDatabaseTracker.h"
  28
  29 #include <mutex>
  30 #include <wtf/NeverDestroyed.h>
  31
  32 namespace WebCore {
  33
  34 namespace SQLiteDatabaseTracker {
  35
  36 static SQLiteDatabaseTrackerClient* s_staticSQLiteDatabaseTrackerClient = nullptr;
  37 static unsigned s_transactionInProgressCounter = 0;
  38
  39 static std::mutex& transactionInProgressMutex()
  40 {
  41     static NeverDestroyed<std::mutex> tipMutex;
  42     return tipMutex;
  43 }
  44
  45 void setClient(SQLiteDatabaseTrackerClient* client)
  46 {
  47     ASSERT(client);
  48     ASSERT(!s_staticSQLiteDatabaseTrackerClient || s_staticSQLiteDatabaseTrackerClient == client);
  49     s_staticSQLiteDatabaseTrackerClient = client;
  50 }
  51
  52 void incrementTransactionInProgressCount()
  53 {
  54     if (!s_staticSQLiteDatabaseTrackerClient)
  55         return;
  56
  57     std::lock_guard<std::mutex> lock(transactionInProgressMutex());
  58
  59     s_transactionInProgressCounter++;
  60     if (s_transactionInProgressCounter == 1)
  61         s_staticSQLiteDatabaseTrackerClient->willBeginFirstTransaction();
  62 }
  63
  64 void decrementTransactionInProgressCount()
  65 {
  66     if (!s_staticSQLiteDatabaseTrackerClient)
  67         return;
  68
  69     std::lock_guard<std::mutex> lock(transactionInProgressMutex());
  70
  71     ASSERT(s_transactionInProgressCounter);
  72     s_transactionInProgressCounter--;
  73
  74     if (!s_transactionInProgressCounter)
  75         s_staticSQLiteDatabaseTrackerClient->didFinishLastTransaction();
  76 }
  77
  78 #if !ASSERT_DISABLED
  79 bool hasTransactionInProgress()
  80 {
  81     return !s_staticSQLiteDatabaseTrackerClient || s_transactionInProgressCounter > 0;
  82 }
  83 #endif
  84
  85 } // namespace SQLiteDatabaseTracker
  86
  87 } // namespace WebCore