Source/WebKitLegacy/win/MemoryStream.h

/*
 * Copyright (C) 2006-2007, 2015 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. 
 */

#ifndef MemoryStream_H
#define MemoryStream_H

#include <objidl.h>

#include <WebCore/COMPtr.h>
#include <WebCore/SharedBuffer.h>
#include <WTF/RefPtr.h>

class MemoryStream final : public IStream
{
public:
    static COMPtr<MemoryStream> createInstance(RefPtr<WebCore::SharedBuffer>&&);

    // IUnknown
    virtual HRESULT STDMETHODCALLTYPE QueryInterface(_In_ REFIID riid, _COM_Outptr_ void** ppvObject);
    virtual ULONG STDMETHODCALLTYPE AddRef();
    virtual ULONG STDMETHODCALLTYPE Release();

    // ISequentialStream
    virtual /* [local] */ HRESULT STDMETHODCALLTYPE Read( 
        /* [length_is][size_is][out] */ void* pv,
        /* [in] */ ULONG cb,
        /* [out] */ ULONG* pcbRead);
    
    virtual /* [local] */ HRESULT STDMETHODCALLTYPE Write( 
        /* [size_is][in] */ const void* pv,
        /* [in] */ ULONG cb,
        /* [out] */ ULONG* pcbWritten);

    // IStream
    virtual /* [local] */ HRESULT STDMETHODCALLTYPE Seek( 
        /* [in] */ LARGE_INTEGER dlibMove,
        /* [in] */ DWORD dwOrigin,
        /* [out] */ ULARGE_INTEGER* plibNewPosition);
    
    virtual HRESULT STDMETHODCALLTYPE SetSize(ULARGE_INTEGER libNewSize);
    
    virtual /* [local] */ HRESULT STDMETHODCALLTYPE CopyTo( 
        /* [unique][in] */ IStream* pstm,
        /* [in] */ ULARGE_INTEGER cb,
        /* [out] */ ULARGE_INTEGER* pcbRead,
        /* [out] */ ULARGE_INTEGER* pcbWritten);
    
    virtual HRESULT STDMETHODCALLTYPE Commit(DWORD grfCommitFlags);
    virtual HRESULT STDMETHODCALLTYPE Revert();
    virtual HRESULT STDMETHODCALLTYPE LockRegion(ULARGE_INTEGER libOffset, ULARGE_INTEGER cb, DWORD dwLockType);
    virtual HRESULT STDMETHODCALLTYPE UnlockRegion(ULARGE_INTEGER libOffset, ULARGE_INTEGER cb, DWORD dwLockType);
    virtual HRESULT STDMETHODCALLTYPE Stat(_Out_ STATSTG*, DWORD grfStatFlag);
    virtual HRESULT STDMETHODCALLTYPE Clone(_COM_Outptr_ IStream** ppstm);

private:
    MemoryStream(RefPtr<WebCore::SharedBuffer>&&);
    ~MemoryStream();

    RefPtr<WebCore::SharedBuffer> m_buffer;
    size_t m_pos { 0 };
    ULONG m_refCount { 0 };
};

#endif