V8Utilities.cpp   [plain text]

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#include "config.h"
#include "V8Utilities.h"

#include <v8.h>

#include "V8CustomBinding.h"
#include "V8Proxy.h"

#include <wtf/Assertions.h>

namespace WebCore {

// Use an array to hold dependents. It works like a ref-counted scheme.
// A value can be added more than once to the DOM object.
void createHiddenDependency(v8::Local<v8::Object> object, v8::Local<v8::Value> value, int cacheIndex)
{
    v8::Local<v8::Value> cache = object->GetInternalField(cacheIndex);
    if (cache->IsNull() || cache->IsUndefined()) {
        cache = v8::Array::New();
        object->SetInternalField(cacheIndex, cache);
    }

    v8::Local<v8::Array> cacheArray = v8::Local<v8::Array>::Cast(cache);
    cacheArray->Set(v8::Integer::New(cacheArray->Length()), value);
}

void removeHiddenDependency(v8::Local<v8::Object> object, v8::Local<v8::Value> value, int cacheIndex)
{
    v8::Local<v8::Value> cache = object->GetInternalField(cacheIndex);
    ASSERT(cache->IsArray());
    v8::Local<v8::Array> cacheArray = v8::Local<v8::Array>::Cast(cache);
    for (int i = cacheArray->Length() - 1; i >= 0; --i) {
        v8::Local<v8::Value> cached = cacheArray->Get(v8::Integer::New(i));
        if (cached->StrictEquals(value)) {
            cacheArray->Delete(i);
            return;
        }
    }

    // We should only get here if we try to remove an event listener that was never added.
    ASSERT_NOT_REACHED();
}

} // namespace WebCore