diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/include/utils/win/SkIStream.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/skia/trunk/include/utils/win/SkIStream.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,131 @@
+
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+
+#ifndef SkIStream_DEFINED
+#define SkIStream_DEFINED
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <ole2.h>
+
+class SkStream;
+class SkWStream;
+
+/**
+ * A bare IStream implementation which properly reference counts
+ * but returns E_NOTIMPL for all ISequentialStream and IStream methods.
+ */
+class SkBaseIStream : public IStream {
+private:
+    LONG _refcount;
+
+protected:
+    explicit SkBaseIStream();
+    virtual ~SkBaseIStream();
+
+public:
+    virtual HRESULT STDMETHODCALLTYPE QueryInterface(REFIID iid
+                                                   , void ** ppvObject);
+    virtual ULONG STDMETHODCALLTYPE AddRef(void);
+    virtual ULONG STDMETHODCALLTYPE Release(void);
+
+    // ISequentialStream Interface
+public:
+    virtual HRESULT STDMETHODCALLTYPE Read(void* pv, ULONG cb, ULONG* pcbRead);
+
+    virtual HRESULT STDMETHODCALLTYPE Write(void const* pv
+                                          , ULONG cb
+                                          , ULONG* pcbWritten);
+
+    // IStream Interface
+public:
+    virtual HRESULT STDMETHODCALLTYPE SetSize(ULARGE_INTEGER);
+
+    virtual HRESULT STDMETHODCALLTYPE CopyTo(IStream*
+                                           , ULARGE_INTEGER
+                                           , ULARGE_INTEGER*
+                                           , ULARGE_INTEGER*);
+
+    virtual HRESULT STDMETHODCALLTYPE Commit(DWORD);
+
+    virtual HRESULT STDMETHODCALLTYPE Revert(void);
+
+    virtual HRESULT STDMETHODCALLTYPE LockRegion(ULARGE_INTEGER
+                                               , ULARGE_INTEGER
+                                               , DWORD);
+
+    virtual HRESULT STDMETHODCALLTYPE UnlockRegion(ULARGE_INTEGER
+                                                 , ULARGE_INTEGER
+                                                 , DWORD);
+
+    virtual HRESULT STDMETHODCALLTYPE Clone(IStream **);
+
+    virtual HRESULT STDMETHODCALLTYPE Seek(LARGE_INTEGER liDistanceToMove
+                                         , DWORD dwOrigin
+                                         , ULARGE_INTEGER* lpNewFilePointer);
+
+    virtual HRESULT STDMETHODCALLTYPE Stat(STATSTG* pStatstg
+                                         , DWORD grfStatFlag);
+};
+
+/**
+ * A minimal read-only IStream implementation which wraps an SkIStream.
+ */
+class SkIStream : public SkBaseIStream {
+private:
+    SkStream *fSkStream;
+    bool fUnrefOnRelease;
+    ULARGE_INTEGER fLocation;
+
+    SkIStream(SkStream* stream, bool unrefOnRelease);
+    virtual ~SkIStream();
+
+public:
+    HRESULT static CreateFromSkStream(SkStream* stream
+                                    , bool unrefOnRelease
+                                    , IStream ** ppStream);
+
+    virtual HRESULT STDMETHODCALLTYPE Read(void* pv, ULONG cb, ULONG* pcbRead);
+
+    virtual HRESULT STDMETHODCALLTYPE Write(void const* pv
+                                          , ULONG cb
+                                          , ULONG* pcbWritten);
+
+    virtual HRESULT STDMETHODCALLTYPE Seek(LARGE_INTEGER liDistanceToMove
+                                         , DWORD dwOrigin
+                                         , ULARGE_INTEGER* lpNewFilePointer);
+
+    virtual HRESULT STDMETHODCALLTYPE Stat(STATSTG* pStatstg
+                                         , DWORD grfStatFlag);
+};
+
+/**
+ * A minimal write-only IStream implementation which wraps an SkWIStream.
+ */
+class SkWIStream : public SkBaseIStream {
+private:
+    SkWStream *fSkWStream;
+
+    SkWIStream(SkWStream* stream);
+    virtual ~SkWIStream();
+
+public:
+    HRESULT static CreateFromSkWStream(SkWStream* stream, IStream ** ppStream);
+
+    virtual HRESULT STDMETHODCALLTYPE Write(void const* pv
+                                          , ULONG cb
+                                          , ULONG* pcbWritten);
+
+    virtual HRESULT STDMETHODCALLTYPE Commit(DWORD);
+
+    virtual HRESULT STDMETHODCALLTYPE Stat(STATSTG* pStatstg
+                                         , DWORD grfStatFlag);
+};
+
+#endif