API/APIShims.h

   1 /*
   2  * Copyright (C) 2009 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 COMPUTER, 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 COMPUTER, 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 #ifndef APIShims_h
  27 #define APIShims_h
  28
  29 #include "CallFrame.h"
  30 #include "GCActivityCallback.h"
  31 #include "JSLock.h"
  32 #include <wtf/WTFThreadData.h>
  33
  34 namespace JSC {
  35
  36 class APIEntryShimWithoutLock {
  37 public:
  38     enum RefGlobalDataTag { DontRefGlobalData = 0, RefGlobalData };
  39
  40 protected:
  41     APIEntryShimWithoutLock(JSGlobalData* globalData, bool registerThread, RefGlobalDataTag shouldRefGlobalData)
  42         : m_shouldRefGlobalData(shouldRefGlobalData)
  43         , m_globalData(globalData)
  44         , m_entryIdentifierTable(wtfThreadData().setCurrentIdentifierTable(globalData->identifierTable))
  45     {
  46         if (shouldRefGlobalData)
  47             m_globalData->ref();
  48         UNUSED_PARAM(registerThread);
  49         if (registerThread)
  50             globalData->heap.machineThreads().addCurrentThread();
  51         if (m_globalData->heap.activityCallback())
  52             m_globalData->heap.activityCallback()->synchronize();
  53     }
  54
  55     ~APIEntryShimWithoutLock()
  56     {
  57         wtfThreadData().setCurrentIdentifierTable(m_entryIdentifierTable);
  58         if (m_shouldRefGlobalData)
  59             m_globalData->deref();
  60     }
  61
  62 protected:
  63     RefGlobalDataTag m_shouldRefGlobalData;
  64     JSGlobalData* m_globalData;
  65     IdentifierTable* m_entryIdentifierTable;
  66 };
  67
  68 class APIEntryShim : public APIEntryShimWithoutLock {
  69 public:
  70     // Normal API entry
  71     APIEntryShim(ExecState* exec, bool registerThread = true)
  72         : APIEntryShimWithoutLock(&exec->globalData(), registerThread, RefGlobalData)
  73     {
  74         init();
  75     }
  76
  77     // This constructor is necessary for HeapTimer to prevent it from accidentally resurrecting
  78     // the ref count of a "dead" JSGlobalData.
  79     APIEntryShim(JSGlobalData* globalData, RefGlobalDataTag refGlobalData, bool registerThread = true)
  80         : APIEntryShimWithoutLock(globalData, registerThread, refGlobalData)
  81     {
  82         init();
  83     }
  84
  85     // JSPropertyNameAccumulator only has a globalData.
  86     APIEntryShim(JSGlobalData* globalData, bool registerThread = true)
  87         : APIEntryShimWithoutLock(globalData, registerThread, RefGlobalData)
  88     {
  89         init();
  90     }
  91
  92     ~APIEntryShim()
  93     {
  94         m_globalData->timeoutChecker.stop();
  95         m_globalData->apiLock().unlock();
  96     }
  97
  98 private:
  99     void init()
 100     {
 101         m_globalData->apiLock().lock();
 102         m_globalData->timeoutChecker.start();
 103     }
 104 };
 105
 106 class APICallbackShim {
 107 public:
 108     APICallbackShim(ExecState* exec)
 109         : m_dropAllLocks(exec)
 110         , m_globalData(&exec->globalData())
 111     {
 112         wtfThreadData().resetCurrentIdentifierTable();
 113     }
 114
 115     ~APICallbackShim()
 116     {
 117         wtfThreadData().setCurrentIdentifierTable(m_globalData->identifierTable);
 118     }
 119
 120 private:
 121     JSLock::DropAllLocks m_dropAllLocks;
 122     JSGlobalData* m_globalData;
 123 };
 124
 125 }
 126
 127 #endif