1 /*

     2  * Copyright (C) 2010 Google 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. AND ITS CONTRIBUTORS ``AS IS''

    14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

    15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

    16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS

    17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

    18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

    19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

    20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

    21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

    22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

    23  * THE POSSIBILITY OF SUCH DAMAGE.

    24  */

    25 

    26 #ifndef JSMainThreadExecState_h

    27 #define JSMainThreadExecState_h

    28 

    29 #include <JSDOMBinding.h>

    30 #ifndef NDEBUG

    31 #include <wtf/MainThread.h>

    32 #endif

    33 #include <wtf/Noncopyable.h>

    34 

    35 namespace WebCore {

    36 

    37 class JSMainThreadExecState : public Noncopyable {

    38 public:

    39     static JSC::ExecState* currentState()

    40     { 

    41         ASSERT(WTF::isMainThread());

    42         return s_mainThreadState;

    43     };

    44     

    45     static JSC::JSValue call(JSC::ExecState* exec, JSC::JSValue functionObject, JSC::CallType callType, const JSC::CallData& callData, JSC::JSValue thisValue, const JSC::ArgList& args)

    46     {

    47         JSMainThreadExecState currentState(exec);

    48         return JSC::call(exec, functionObject, callType, callData, thisValue, args);

    49     };

    50 

    51     static JSC::Completion evaluate(JSC::ExecState* exec, JSC::ScopeChain& chain, const JSC::SourceCode& source, JSC::JSValue thisValue)

    52     {

    53         JSMainThreadExecState currentState(exec);

    54         return JSC::evaluate(exec, chain, source, thisValue);

    55     };

    56 

    57 protected:

    58     explicit JSMainThreadExecState(JSC::ExecState* exec)

    59         : m_previousState(s_mainThreadState)

    60     {

    61         ASSERT(WTF::isMainThread());

    62         s_mainThreadState = exec;

    63     };

    64     

    65     ~JSMainThreadExecState()

    66     {

    67         ASSERT(WTF::isMainThread());

    68         s_mainThreadState = m_previousState;

    69     }

    70 

    71 private:

    72     static JSC::ExecState* s_mainThreadState;

    73     JSC::ExecState* m_previousState;

    74 };

    75 

    76 // Null state prevents origin security checks.

    77 class JSMainThreadNullState : private JSMainThreadExecState {

    78 public:

    79     explicit JSMainThreadNullState() : JSMainThreadExecState(0) {};

    80 };

    81 

    82 } // namespace WebCore

    83 

    84 #endif // JSMainThreadExecState_h