Source/WebCore/bindings/js/SerializedScriptValue.h

/*
 * Copyright (C) 2009, 2013, 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
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 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */

#pragma once

#include "ExceptionOr.h"
#include "ImageBuffer.h"
#include <JavaScriptCore/ArrayBuffer.h>
#include <JavaScriptCore/JSCJSValue.h>
#include <JavaScriptCore/Strong.h>
#include <wtf/Forward.h>
#include <wtf/Function.h>
#include <wtf/Gigacage.h>
#include <wtf/text/WTFString.h>

typedef const struct OpaqueJSContext* JSContextRef;
typedef const struct OpaqueJSValue* JSValueRef;

#if ENABLE(WEBASSEMBLY)
namespace JSC { namespace Wasm {
class Module;
} }
#endif

namespace WebCore {

class IDBValue;
class ImageBitmap;
class MessagePort;
class SharedBuffer;
enum class SerializationReturnCode;

enum class SerializationErrorMode { NonThrowing, Throwing };
enum class SerializationContext { Default, WorkerPostMessage, WindowPostMessage };

using ArrayBufferContentsArray = Vector<JSC::ArrayBufferContents>;
#if ENABLE(WEBASSEMBLY)
using WasmModuleArray = Vector<RefPtr<JSC::Wasm::Module>>;
#endif

class SerializedScriptValue : public ThreadSafeRefCounted<SerializedScriptValue> {
public:
    WEBCORE_EXPORT static RefPtr<SerializedScriptValue> create(JSC::ExecState&, JSC::JSValue, SerializationErrorMode = SerializationErrorMode::Throwing);

    WEBCORE_EXPORT static ExceptionOr<Ref<SerializedScriptValue>> create(JSC::ExecState&, JSC::JSValue, Vector<JSC::Strong<JSC::JSObject>>&& transfer, Vector<RefPtr<MessagePort>>&, SerializationContext = SerializationContext::Default);

    WEBCORE_EXPORT static RefPtr<SerializedScriptValue> create(StringView);
    static Ref<SerializedScriptValue> adopt(Vector<uint8_t>&& buffer)
    {
        return adoptRef(*new SerializedScriptValue(WTFMove(buffer)));
    }

    static Ref<SerializedScriptValue> nullValue();

    WEBCORE_EXPORT JSC::JSValue deserialize(JSC::ExecState&, JSC::JSGlobalObject*, SerializationErrorMode = SerializationErrorMode::Throwing);
    WEBCORE_EXPORT JSC::JSValue deserialize(JSC::ExecState&, JSC::JSGlobalObject*, const Vector<RefPtr<MessagePort>>&, SerializationErrorMode = SerializationErrorMode::Throwing);
    JSC::JSValue deserialize(JSC::ExecState&, JSC::JSGlobalObject*, const Vector<RefPtr<MessagePort>>&, const Vector<String>& blobURLs, const Vector<String>& blobFilePaths, SerializationErrorMode = SerializationErrorMode::Throwing);

    static uint32_t wireFormatVersion();

    String toString();

    // API implementation helpers. These don't expose special behavior for ArrayBuffers or MessagePorts.
    WEBCORE_EXPORT static RefPtr<SerializedScriptValue> create(JSContextRef, JSValueRef, JSValueRef* exception);
    WEBCORE_EXPORT JSValueRef deserialize(JSContextRef, JSValueRef* exception);

    const Vector<uint8_t>& data() const { return m_data; }
    bool hasBlobURLs() const { return !m_blobURLs.isEmpty(); }

#if ENABLE(INDEXED_DATABASE)
    Vector<String> blobURLsIsolatedCopy() const;
    void writeBlobsToDiskForIndexedDB(WTF::Function<void (const IDBValue&)>&& completionHandler);
    IDBValue writeBlobsToDiskForIndexedDBSynchronously();
#endif // ENABLE(INDEXED_DATABASE)

    static Ref<SerializedScriptValue> createFromWireBytes(Vector<uint8_t>&& data)
    {
        return adoptRef(*new SerializedScriptValue(WTFMove(data)));
    }
    const Vector<uint8_t>& toWireBytes() const { return m_data; }

    template<class Encoder> void encode(Encoder&) const;
    template<class Decoder> static RefPtr<SerializedScriptValue> decode(Decoder&);

    WEBCORE_EXPORT ~SerializedScriptValue();

private:
    WEBCORE_EXPORT SerializedScriptValue(Vector<unsigned char>&&);
    WEBCORE_EXPORT SerializedScriptValue(Vector<unsigned char>&&, std::unique_ptr<ArrayBufferContentsArray>);
    SerializedScriptValue(Vector<unsigned char>&&, const Vector<String>& blobURLs, std::unique_ptr<ArrayBufferContentsArray>, std::unique_ptr<ArrayBufferContentsArray> sharedBuffers, Vector<std::pair<std::unique_ptr<ImageBuffer>, bool>>&& imageBuffers
#if ENABLE(WEBASSEMBLY)
        , std::unique_ptr<WasmModuleArray>
#endif
        );

    Vector<unsigned char> m_data;
    std::unique_ptr<ArrayBufferContentsArray> m_arrayBufferContentsArray;
    std::unique_ptr<ArrayBufferContentsArray> m_sharedBufferContentsArray;
    Vector<std::pair<std::unique_ptr<ImageBuffer>, bool>> m_imageBuffers;
#if ENABLE(WEBASSEMBLY)
    std::unique_ptr<WasmModuleArray> m_wasmModulesArray;
#endif
    Vector<String> m_blobURLs;
};

template<class Encoder>
void SerializedScriptValue::encode(Encoder& encoder) const
{
    encoder << m_data;

    auto hasArray = m_arrayBufferContentsArray && m_arrayBufferContentsArray->size();
    encoder << hasArray;

    if (!hasArray)
        return;

    encoder << static_cast<uint64_t>(m_arrayBufferContentsArray->size());
    for (const auto &arrayBufferContents : *m_arrayBufferContentsArray) {
        encoder << arrayBufferContents.sizeInBytes();
        encoder.encodeFixedLengthData(static_cast<const uint8_t*>(arrayBufferContents.data()), arrayBufferContents.sizeInBytes(), 1);
    }
}

template<class Decoder>
RefPtr<SerializedScriptValue> SerializedScriptValue::decode(Decoder& decoder)
{
    Vector<uint8_t> data;
    if (!decoder.decode(data))
        return nullptr;

    bool hasArray;
    if (!decoder.decode(hasArray))
        return nullptr;

    if (!hasArray)
        return adoptRef(*new SerializedScriptValue(WTFMove(data)));

    uint64_t arrayLength;
    if (!decoder.decode(arrayLength))
        return nullptr;
    ASSERT(arrayLength);

    auto arrayBufferContentsArray = std::make_unique<ArrayBufferContentsArray>();
    while (arrayLength--) {
        unsigned bufferSize;
        if (!decoder.decode(bufferSize))
            return nullptr;

        auto buffer = Gigacage::tryMalloc(Gigacage::Primitive, bufferSize);
        auto destructor = [] (void* ptr) {
            Gigacage::free(Gigacage::Primitive, ptr);
        };
        if (!decoder.decodeFixedLengthData(static_cast<uint8_t*>(buffer), bufferSize, 1)) {
            destructor(buffer);
            return nullptr;
        }
        arrayBufferContentsArray->append({ buffer, bufferSize, WTFMove(destructor) });
    }

    return adoptRef(*new SerializedScriptValue(WTFMove(data), WTFMove(arrayBufferContentsArray)));
}


}