root/Source/core/dom/Microtask.cpp

DEFINITIONS

1. performCheckpoint
2. microtaskFunctionCallback
3. enqueueMicrotask

/*
 * Copyright (C) 2013 Google 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.
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 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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#include "config.h"
#include "core/dom/Microtask.h"

#include "bindings/v8/V8PerIsolateData.h"
#include "wtf/Vector.h"
#include <v8.h>

namespace WebCore {

void Microtask::performCheckpoint()
{
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    V8PerIsolateData* isolateData = V8PerIsolateData::from(isolate);
    ASSERT(isolateData);
    if (isolateData->recursionLevel() || isolateData->performingMicrotaskCheckpoint())
        return;
    isolateData->setPerformingMicrotaskCheckpoint(true);

    v8::HandleScope handleScope(isolate);
    v8::Local<v8::Context> context = isolateData->ensureDomInJSContext();
    v8::Context::Scope scope(context);
    v8::V8::RunMicrotasks(isolate);

    isolateData->setPerformingMicrotaskCheckpoint(false);
}

COMPILE_ASSERT(sizeof(void*) == sizeof(MicrotaskCallback), VoidPtrAndFunctionPtrAreSameSize);

static void microtaskFunctionCallback(const v8::FunctionCallbackInfo<v8::Value>& info)
{
    MicrotaskCallback callback =
        reinterpret_cast<MicrotaskCallback>(reinterpret_cast<intptr_t>(
            info.Data().As<v8::External>()->Value()));
    (*callback)();
}

void Microtask::enqueueMicrotask(MicrotaskCallback callback)
{
    v8::Isolate* isolate = v8::Isolate::GetCurrent();
    V8PerIsolateData* isolateData = V8PerIsolateData::from(isolate);
    v8::HandleScope handleScope(isolate);
    v8::Local<v8::Context> context = isolateData->ensureDomInJSContext();
    v8::Context::Scope scope(context);
    v8::Local<v8::External> handler =
        v8::External::New(isolate,
            reinterpret_cast<void*>(reinterpret_cast<intptr_t>(callback)));
    v8::V8::EnqueueMicrotask(isolate, v8::Function::New(isolate, &microtaskFunctionCallback, handler));
}

} // namespace WebCore