dwrite: Implement IDWriteFont::Equals().

dlls/dwrite/font.c

@@ -295,6 +295,8 @@ static inline struct dwrite_font *impl_from_IDWriteFont3(IDWriteFont3 *iface)
     return CONTAINING_RECORD(iface, struct dwrite_font, IDWriteFont3_iface);
 }
 
+static struct dwrite_font *unsafe_impl_from_IDWriteFont(IDWriteFont *iface);
+
 static inline struct dwrite_fontfile *impl_from_IDWriteFontFile(IDWriteFontFile *iface)
 {
     return CONTAINING_RECORD(iface, struct dwrite_fontfile, IDWriteFontFile_iface);
@@ -467,6 +469,29 @@ void fontface_detach_from_cache(IDWriteFontFace5 *iface)
     fontface->cached = NULL;
 }
 
+static BOOL is_same_fontfile(IDWriteFontFile *left, IDWriteFontFile *right)
+{
+    UINT32 left_key_size, right_key_size;
+    const void *left_key, *right_key;
+    HRESULT hr;
+
+    if (left == right)
+        return TRUE;
+
+    hr = IDWriteFontFile_GetReferenceKey(left, &left_key, &left_key_size);
+    if (FAILED(hr))
+        return FALSE;
+
+    hr = IDWriteFontFile_GetReferenceKey(right, &right_key, &right_key_size);
+    if (FAILED(hr))
+        return FALSE;
+
+    if (left_key_size != right_key_size)
+        return FALSE;
+
+    return !memcmp(left_key, right_key, left_key_size);
+}
+
 static HRESULT WINAPI dwritefontface_QueryInterface(IDWriteFontFace5 *iface, REFIID riid, void **obj)
 {
     struct dwrite_fontface *fontface = impl_from_IDWriteFontFace5(iface);
@@ -1814,11 +1839,18 @@ static HRESULT WINAPI dwritefont3_CreateFontFace(IDWriteFont3 *iface, IDWriteFon
     return get_fontface_from_font(font, (IDWriteFontFace5 **)fontface);
 }
 
-static BOOL WINAPI dwritefont3_Equals(IDWriteFont3 *iface, IDWriteFont *font)
+static BOOL WINAPI dwritefont3_Equals(IDWriteFont3 *iface, IDWriteFont *other)
 {
-    struct dwrite_font *This = impl_from_IDWriteFont3(iface);
-    FIXME("(%p)->(%p): stub\n", This, font);
-    return FALSE;
+    struct dwrite_font *font = impl_from_IDWriteFont3(iface), *other_font;
+
+    TRACE("%p, %p.\n", iface, other);
+
+    if (!(other_font = unsafe_impl_from_IDWriteFont(other)))
+        return FALSE;
+
+    return font->data->face_index == other_font->data->face_index
+            && font->data->simulations == other_font->data->simulations
+            && is_same_fontfile(font->data->file, other_font->data->file);
 }
 
 static HRESULT WINAPI dwritefont3_GetFontFaceReference(IDWriteFont3 *iface, IDWriteFontFaceReference **reference)
@@ -2687,29 +2719,6 @@ static HRESULT WINAPI dwritefontcollection_FindFamilyName(IDWriteFontCollection3
     return S_OK;
 }
 
-static BOOL is_same_fontfile(IDWriteFontFile *left, IDWriteFontFile *right)
-{
-    UINT32 left_key_size, right_key_size;
-    const void *left_key, *right_key;
-    HRESULT hr;
-
-    if (left == right)
-        return TRUE;
-
-    hr = IDWriteFontFile_GetReferenceKey(left, &left_key, &left_key_size);
-    if (FAILED(hr))
-        return FALSE;
-
-    hr = IDWriteFontFile_GetReferenceKey(right, &right_key, &right_key_size);
-    if (FAILED(hr))
-        return FALSE;
-
-    if (left_key_size != right_key_size)
-        return FALSE;
-
-    return !memcmp(left_key, right_key, left_key_size);
-}
-
 static HRESULT WINAPI dwritefontcollection_GetFontFromFontFace(IDWriteFontCollection3 *iface, IDWriteFontFace *face,
         IDWriteFont **font)
 {