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/*
* Copyright (C) 2009 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef APIShims_h
#define APIShims_h
#include "CallFrame.h"
#include "GCActivityCallback.h"
#include "IncrementalSweeper.h"
#include "JSLock.h"
#include <wtf/WTFThreadData.h>
namespace JSC {
class APIEntryShimWithoutLock {
protected:
APIEntryShimWithoutLock(VM* vm, bool registerThread)
: m_vm(vm)
, m_entryIdentifierTable(wtfThreadData().setCurrentIdentifierTable(vm->identifierTable))
{
if (registerThread)
vm->heap.machineThreads().addCurrentThread();
}
~APIEntryShimWithoutLock()
{
wtfThreadData().setCurrentIdentifierTable(m_entryIdentifierTable);
}
protected:
RefPtr<VM> m_vm;
IdentifierTable* m_entryIdentifierTable;
};
class APIEntryShim : public APIEntryShimWithoutLock {
public:
// Normal API entry
APIEntryShim(ExecState* exec, bool registerThread = true)
: APIEntryShimWithoutLock(&exec->vm(), registerThread)
, m_lockHolder(exec->vm().exclusiveThread ? 0 : exec)
{
}
// JSPropertyNameAccumulator only has a vm.
APIEntryShim(VM* vm, bool registerThread = true)
: APIEntryShimWithoutLock(vm, registerThread)
, m_lockHolder(vm->exclusiveThread ? 0 : vm)
{
}
~APIEntryShim()
{
// Destroying our JSLockHolder should also destroy the VM.
m_vm.clear();
}
private:
JSLockHolder m_lockHolder;
};
class APICallbackShim {
public:
APICallbackShim(ExecState* exec)
: m_dropAllLocks(shouldDropAllLocks(exec->vm()) ? exec : nullptr)
, m_vm(&exec->vm())
{
wtfThreadData().resetCurrentIdentifierTable();
}
APICallbackShim(VM& vm)
: m_dropAllLocks(shouldDropAllLocks(vm) ? &vm : nullptr)
, m_vm(&vm)
{
wtfThreadData().resetCurrentIdentifierTable();
}
~APICallbackShim()
{
wtfThreadData().setCurrentIdentifierTable(m_vm->identifierTable);
}
private:
static bool shouldDropAllLocks(VM& vm)
{
if (vm.exclusiveThread)
return false;
// If the VM is in the middle of being destroyed then we don't want to resurrect it
// by allowing DropAllLocks to ref it. By this point the APILock has already been
// released anyways, so it doesn't matter that DropAllLocks is a no-op.
if (!vm.refCount())
return false;
return true;
}
JSLock::DropAllLocks m_dropAllLocks;
VM* m_vm;
};
}
#endif
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