Source/WebCore/bindings/js/StructuredClone.cpp

/*
 * Copyright (C) 2016 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 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 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.
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 */

#include "config.h"
#include "StructuredClone.h"

#include "JSDOMBinding.h"
#include "JSDOMExceptionHandling.h"
#include <JavaScriptCore/JSTypedArrays.h>

namespace WebCore {
using namespace JSC;

enum class CloneMode {
    Full,
    Partial,
};

static EncodedJSValue cloneArrayBufferImpl(JSGlobalObject* lexicalGlobalObject, CallFrame* callFrame, CloneMode mode)
{
    VM& vm = lexicalGlobalObject->vm();

    ASSERT(lexicalGlobalObject);
    ASSERT(callFrame->argumentCount());
    ASSERT(callFrame->lexicalGlobalObject(vm) == lexicalGlobalObject);

    auto* buffer = toUnsharedArrayBuffer(vm, callFrame->uncheckedArgument(0));
    if (!buffer) {
        auto scope = DECLARE_THROW_SCOPE(vm);
        throwDataCloneError(*lexicalGlobalObject, scope);
        return { };
    }
    if (mode == CloneMode::Partial) {
        ASSERT(callFrame->argumentCount() == 3);
        int srcByteOffset = static_cast<int>(callFrame->uncheckedArgument(1).toNumber(lexicalGlobalObject));
        int srcLength = static_cast<int>(callFrame->uncheckedArgument(2).toNumber(lexicalGlobalObject));
        return JSValue::encode(JSArrayBuffer::create(lexicalGlobalObject->vm(), lexicalGlobalObject->arrayBufferStructure(ArrayBufferSharingMode::Default), buffer->slice(srcByteOffset, srcByteOffset + srcLength)));
    }
    return JSValue::encode(JSArrayBuffer::create(lexicalGlobalObject->vm(), lexicalGlobalObject->arrayBufferStructure(ArrayBufferSharingMode::Default), ArrayBuffer::tryCreate(buffer->data(), buffer->byteLength())));
}

JSC_DEFINE_HOST_FUNCTION(cloneArrayBuffer, (JSGlobalObject* globalObject, CallFrame* callFrame))
{
    return cloneArrayBufferImpl(globalObject, callFrame, CloneMode::Partial);
}

JSC_DEFINE_HOST_FUNCTION(structuredCloneForStream, (JSGlobalObject* globalObject, CallFrame* callFrame))
{
    ASSERT(callFrame);
    ASSERT(callFrame->argumentCount());

    VM& vm = globalObject->vm();
    auto scope = DECLARE_THROW_SCOPE(vm);

    JSValue value = callFrame->uncheckedArgument(0);

    if (value.inherits<JSArrayBuffer>(vm))
        RELEASE_AND_RETURN(scope, cloneArrayBufferImpl(globalObject, callFrame, CloneMode::Full));

    if (value.inherits<JSArrayBufferView>(vm)) {
        auto* bufferView = jsCast<JSArrayBufferView*>(value);
        ASSERT(bufferView);

        auto* buffer = bufferView->unsharedBuffer();
        if (!buffer) {
            throwDataCloneError(*globalObject, scope);
            return { };
        }
        auto bufferClone = ArrayBuffer::tryCreate(buffer->data(), buffer->byteLength());
        Structure* structure = bufferView->structure(vm);

#define CLONE_TYPED_ARRAY(name) \
        do { \
            if (bufferView->inherits<JS##name##Array>(vm)) \
                RELEASE_AND_RETURN(scope, JSValue::encode(JS##name##Array::create(globalObject, structure, WTFMove(bufferClone), bufferView->byteOffset(), bufferView->length()))); \
        } while (0);

        FOR_EACH_TYPED_ARRAY_TYPE_EXCLUDING_DATA_VIEW(CLONE_TYPED_ARRAY)

#undef CLONE_TYPED_ARRAY

        if (value.inherits<JSDataView>(vm))
            RELEASE_AND_RETURN(scope, JSValue::encode(JSDataView::create(globalObject, structure, WTFMove(bufferClone), bufferView->byteOffset(), bufferView->length())));
    }

    throwTypeError(globalObject, scope, "structuredClone not implemented for non-ArrayBuffer / non-ArrayBufferView"_s);
    return { };
}

} // namespace WebCore