API/JSCallbackFunction.cpp

   1 /*
   2  * Copyright (C) 2006, 2008 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:
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   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 #include "config.h"
  27 #include "JSCallbackFunction.h"
  28
  29 #include "APIShims.h"
  30 #include "APICast.h"
  31 #include "CodeBlock.h"
  32 #include "Error.h"
  33 #include "ExceptionHelpers.h"
  34 #include "FunctionPrototype.h"
  35 #include "JSFunction.h"
  36 #include "JSGlobalObject.h"
  37 #include "JSLock.h"
  38 #include "Operations.h"
  39 #include <wtf/Vector.h>
  40
  41 namespace JSC {
  42
  43 ASSERT_HAS_TRIVIAL_DESTRUCTOR(JSCallbackFunction);
  44
  45 const ClassInfo JSCallbackFunction::s_info = { "CallbackFunction", &InternalFunction::s_info, 0, 0, CREATE_METHOD_TABLE(JSCallbackFunction) };
  46
  47 JSCallbackFunction::JSCallbackFunction(JSGlobalObject* globalObject, Structure* structure, JSObjectCallAsFunctionCallback callback)
  48     : InternalFunction(globalObject, structure)
  49     , m_callback(callback)
  50 {
  51 }
  52
  53 void JSCallbackFunction::finishCreation(VM& vm, const String& name)
  54 {
  55     Base::finishCreation(vm, name);
  56     ASSERT(inherits(&s_info));
  57 }
  58
  59 JSCallbackFunction* JSCallbackFunction::create(ExecState* exec, JSGlobalObject* globalObject, JSObjectCallAsFunctionCallback callback, const String& name)
  60 {
  61     JSCallbackFunction* function = new (NotNull, allocateCell<JSCallbackFunction>(*exec->heap())) JSCallbackFunction(globalObject, globalObject->callbackFunctionStructure(), callback);
  62     function->finishCreation(exec->vm(), name);
  63     return function;
  64 }
  65
  66 EncodedJSValue JSCallbackFunction::call(ExecState* exec)
  67 {
  68     JSContextRef execRef = toRef(exec);
  69     JSObjectRef functionRef = toRef(exec->callee());
  70     JSObjectRef thisObjRef = toRef(exec->hostThisValue().toThisObject(exec));
  71
  72     size_t argumentCount = exec->argumentCount();
  73     Vector<JSValueRef, 16> arguments;
  74     arguments.reserveInitialCapacity(argumentCount);
  75     for (size_t i = 0; i < argumentCount; ++i)
  76         arguments.uncheckedAppend(toRef(exec, exec->argument(i)));
  77
  78     JSValueRef exception = 0;
  79     JSValueRef result;
  80     {
  81         APICallbackShim callbackShim(exec);
  82         result = jsCast<JSCallbackFunction*>(toJS(functionRef))->m_callback(execRef, functionRef, thisObjRef, argumentCount, arguments.data(), &exception);
  83     }
  84     if (exception)
  85         throwError(exec, toJS(exec, exception));
  86
  87     // result must be a valid JSValue.
  88     if (!result)
  89         return JSValue::encode(jsUndefined());
  90
  91     return JSValue::encode(toJS(exec, result));
  92 }
  93
  94 CallType JSCallbackFunction::getCallData(JSCell*, CallData& callData)
  95 {
  96     callData.native.function = call;
  97     return CallTypeHost;
  98 }
  99
 100 } // namespace JSC