windowscodecs: Implement GetFrameCount and GetFrame for the GIF decoder.

dlls/windowscodecs/gifformat.c

@@ -42,6 +42,134 @@ typedef struct {
     GifFileType *gif;
 } GifDecoder;
 
+typedef struct {
+    const IWICBitmapFrameDecodeVtbl *lpVtbl;
+    LONG ref;
+    SavedImage *frame;
+    GifDecoder *parent;
+} GifFrameDecode;
+
+static HRESULT WINAPI GifFrameDecode_QueryInterface(IWICBitmapFrameDecode *iface, REFIID iid,
+    void **ppv)
+{
+    GifFrameDecode *This = (GifFrameDecode*)iface;
+    TRACE("(%p,%s,%p)\n", iface, debugstr_guid(iid), ppv);
+
+    if (!ppv) return E_INVALIDARG;
+
+    if (IsEqualIID(&IID_IUnknown, iid) ||
+        IsEqualIID(&IID_IWICBitmapSource, iid) ||
+        IsEqualIID(&IID_IWICBitmapFrameDecode, iid))
+    {
+        *ppv = This;
+    }
+    else
+    {
+        *ppv = NULL;
+        return E_NOINTERFACE;
+    }
+
+    IUnknown_AddRef((IUnknown*)*ppv);
+    return S_OK;
+}
+
+static ULONG WINAPI GifFrameDecode_AddRef(IWICBitmapFrameDecode *iface)
+{
+    GifFrameDecode *This = (GifFrameDecode*)iface;
+    ULONG ref = InterlockedIncrement(&This->ref);
+
+    TRACE("(%p) refcount=%u\n", iface, ref);
+
+    return ref;
+}
+
+static ULONG WINAPI GifFrameDecode_Release(IWICBitmapFrameDecode *iface)
+{
+    GifFrameDecode *This = (GifFrameDecode*)iface;
+    ULONG ref = InterlockedDecrement(&This->ref);
+
+    TRACE("(%p) refcount=%u\n", iface, ref);
+
+    if (ref == 0)
+    {
+        IUnknown_Release((IUnknown*)This->parent);
+        HeapFree(GetProcessHeap(), 0, This);
+    }
+
+    return ref;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetSize(IWICBitmapFrameDecode *iface,
+    UINT *puiWidth, UINT *puiHeight)
+{
+    FIXME("(%p,%p,%p): stub\n", iface, puiWidth, puiHeight);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetPixelFormat(IWICBitmapFrameDecode *iface,
+    WICPixelFormatGUID *pPixelFormat)
+{
+    memcpy(pPixelFormat, &GUID_WICPixelFormat8bppIndexed, sizeof(GUID));
+
+    return S_OK;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetResolution(IWICBitmapFrameDecode *iface,
+    double *pDpiX, double *pDpiY)
+{
+    FIXME("(%p,%p,%p): stub\n", iface, pDpiX, pDpiY);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI GifFrameDecode_CopyPalette(IWICBitmapFrameDecode *iface,
+    IWICPalette *pIPalette)
+{
+    FIXME("(%p,%p): stub\n", iface, pIPalette);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI GifFrameDecode_CopyPixels(IWICBitmapFrameDecode *iface,
+    const WICRect *prc, UINT cbStride, UINT cbBufferSize, BYTE *pbBuffer)
+{
+    FIXME("(%p,%p,%u,%u,%p): stub\n", iface, prc, cbStride, cbBufferSize, pbBuffer);
+    return E_NOTIMPL;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetMetadataQueryReader(IWICBitmapFrameDecode *iface,
+    IWICMetadataQueryReader **ppIMetadataQueryReader)
+{
+    TRACE("(%p,%p)\n", iface, ppIMetadataQueryReader);
+    return WINCODEC_ERR_UNSUPPORTEDOPERATION;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetColorContexts(IWICBitmapFrameDecode *iface,
+    UINT cCount, IWICColorContext **ppIColorContexts, UINT *pcActualCount)
+{
+    TRACE("(%p,%u,%p,%p)\n", iface, cCount, ppIColorContexts, pcActualCount);
+    return WINCODEC_ERR_UNSUPPORTEDOPERATION;
+}
+
+static HRESULT WINAPI GifFrameDecode_GetThumbnail(IWICBitmapFrameDecode *iface,
+    IWICBitmapSource **ppIThumbnail)
+{
+    TRACE("(%p,%p)\n", iface, ppIThumbnail);
+    return WINCODEC_ERR_CODECNOTHUMBNAIL;
+}
+
+static const IWICBitmapFrameDecodeVtbl GifFrameDecode_Vtbl = {
+    GifFrameDecode_QueryInterface,
+    GifFrameDecode_AddRef,
+    GifFrameDecode_Release,
+    GifFrameDecode_GetSize,
+    GifFrameDecode_GetPixelFormat,
+    GifFrameDecode_GetResolution,
+    GifFrameDecode_CopyPalette,
+    GifFrameDecode_CopyPixels,
+    GifFrameDecode_GetMetadataQueryReader,
+    GifFrameDecode_GetColorContexts,
+    GifFrameDecode_GetThumbnail
+};
+
 static HRESULT WINAPI GifDecoder_QueryInterface(IWICBitmapDecoder *iface, REFIID iid,
     void **ppv)
 {
@@ -199,15 +327,41 @@ static HRESULT WINAPI GifDecoder_GetThumbnail(IWICBitmapDecoder *iface,
 static HRESULT WINAPI GifDecoder_GetFrameCount(IWICBitmapDecoder *iface,
     UINT *pCount)
 {
-    FIXME("(%p,%p): stub\n", iface, pCount);
-    return E_NOTIMPL;
+    GifDecoder *This = (GifDecoder*)iface;
+    TRACE("(%p,%p)\n", iface, pCount);
+
+    if (!This->initialized) return WINCODEC_ERR_NOTINITIALIZED;
+
+    *pCount = This->gif->ImageCount;
+
+    TRACE("<- %u\n", *pCount);
+
+    return S_OK;
 }
 
 static HRESULT WINAPI GifDecoder_GetFrame(IWICBitmapDecoder *iface,
     UINT index, IWICBitmapFrameDecode **ppIBitmapFrame)
 {
-    FIXME("(%p,%u,%p): stub\n", iface, index, ppIBitmapFrame);
-    return E_NOTIMPL;
+    GifDecoder *This = (GifDecoder*)iface;
+    GifFrameDecode *result;
+    TRACE("(%p,%u,%p)\n", iface, index, ppIBitmapFrame);
+
+    if (!This->initialized) return WINCODEC_ERR_NOTINITIALIZED;
+
+    if (index >= This->gif->ImageCount) return E_INVALIDARG;
+
+    result = HeapAlloc(GetProcessHeap(), 0, sizeof(GifFrameDecode));
+    if (!result) return E_OUTOFMEMORY;
+
+    result->lpVtbl = &GifFrameDecode_Vtbl;
+    result->ref = 1;
+    result->frame = &This->gif->SavedImages[index];
+    IWICBitmapDecoder_AddRef(iface);
+    result->parent = This;
+
+    *ppIBitmapFrame = (IWICBitmapFrameDecode*)result;
+
+    return S_OK;
 }
 
 static const IWICBitmapDecoderVtbl GifDecoder_Vtbl = {