Thumbnailer for windows

thumbnailer/TenmonThumbnailProvider.cpp

@@ -0,0 +1,116 @@
+// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
+// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
+// PARTICULAR PURPOSE.
+//
+// Copyright (c) Microsoft Corporation. All rights reserved
+
+#include <shlwapi.h>
+#include <thumbcache.h> // For IThumbnailProvider.
+#include <new>
+#include "libxisf.h"
+
+bool loadXISF(const LibXISF::ByteArray &data, HBITMAP *hbmp, UINT thumbSize);
+
+class TenmonThumbProvider : public IInitializeWithStream,
+                             public IThumbnailProvider
+{
+public:
+    TenmonThumbProvider() : _cRef(1), _pStream(NULL)
+    {
+    }
+
+    virtual ~TenmonThumbProvider()
+    {
+        if (_pStream)
+        {
+            _pStream->Release();
+        }
+    }
+
+    // IUnknown
+    IFACEMETHODIMP QueryInterface(REFIID riid, void **ppv)
+    {
+        static const QITAB qit[] =
+        {
+            QITABENT(TenmonThumbProvider, IInitializeWithStream),
+            QITABENT(TenmonThumbProvider, IThumbnailProvider),
+            { 0 },
+        };
+        return QISearch(this, qit, riid, ppv);
+    }
+
+    IFACEMETHODIMP_(ULONG) AddRef()
+    {
+        return InterlockedIncrement(&_cRef);
+    }
+
+    IFACEMETHODIMP_(ULONG) Release()
+    {
+        ULONG cRef = InterlockedDecrement(&_cRef);
+        if (!cRef)
+        {
+            delete this;
+        }
+        return cRef;
+    }
+
+    // IInitializeWithStream
+    IFACEMETHODIMP Initialize(IStream *pStream, DWORD grfMode);
+
+    // IThumbnailProvider
+    IFACEMETHODIMP GetThumbnail(UINT cx, HBITMAP *phbmp, WTS_ALPHATYPE *pdwAlpha);
+
+private:
+
+    long _cRef;
+    IStream *_pStream;     // provided during initialization.
+};
+
+HRESULT TenmonThumbnailer_CreateInstance(REFIID riid, void **ppv)
+{
+    TenmonThumbProvider *pNew = new (std::nothrow) TenmonThumbProvider();
+    HRESULT hr = pNew ? S_OK : E_OUTOFMEMORY;
+    if (SUCCEEDED(hr))
+    {
+        hr = pNew->QueryInterface(riid, ppv);
+        pNew->Release();
+    }
+    return hr;
+}
+
+// IInitializeWithStream
+IFACEMETHODIMP TenmonThumbProvider::Initialize(IStream *pStream, DWORD)
+{
+    HRESULT hr = E_UNEXPECTED;  // can only be inited once
+    if (_pStream == NULL)
+    {
+        // take a reference to the stream if we have not been inited yet
+        hr = pStream->QueryInterface(&_pStream);
+    }
+    return hr;
+}
+
+// IThumbnailProvider
+IFACEMETHODIMP TenmonThumbProvider::GetThumbnail(UINT cx, HBITMAP *phbmp, WTS_ALPHATYPE *pdwAlpha)
+{
+    LibXISF::ByteArray data;
+    ULONG readSize = 0;
+    ULONG read;
+    data.resize(1024*1024);
+
+    while(_pStream->Read(data.data() + readSize, data.size() - readSize, &read) == S_OK)
+    {
+        readSize += read;
+        data.resize(data.size() + 1024*1024);
+    }
+    readSize += read;
+
+    *pdwAlpha = WTSAT_RGB;
+
+    data.resize(readSize);
+    if(loadXISF(data, phbmp, cx))
+        return S_OK;
+    else
+        return E_FAIL;
+}