oledb32: DataConvert support DBTYPE_VARIANT -> DBTYPE_R4.

dlls/oledb32/convert.c

@@ -343,6 +343,11 @@ static HRESULT WINAPI convert_DataConvert(IDataConvert* iface,
         case DBTYPE_UI4:         hr = VarR4FromUI4(*(DWORD*)src, d);             break;
         case DBTYPE_I8:          hr = VarR4FromI8(*(LONGLONG*)src, d);           break;
         case DBTYPE_UI8:         hr = VarR4FromUI8(*(ULONGLONG*)src, d);         break;
+        case DBTYPE_VARIANT:
+            VariantInit(&tmp);
+            if ((hr = VariantChangeType(&tmp, (VARIANT*)src, 0, VT_R4)) == S_OK)
+                *d = V_R4(&tmp);
+            break;
         default: FIXME("Unimplemented conversion %04x -> R4\n", src_type); return E_NOTIMPL;
         }
         break;

dlls/oledb32/tests/convert.c

@@ -2580,6 +2580,15 @@ static void test_converttor4(void)
     ok(hr == S_OK, "got %08x\n", hr);
     ok(dst_status == DBSTATUS_S_ISNULL, "got %08x\n", dst_status);
     ok(dst_len == 44, "got %ld\n", dst_len);
+
+    dst_len = dst = 0x1234;
+    V_VT(&v) = VT_I2;
+    V_I2(&v) = 0x4321;
+    hr = IDataConvert_DataConvert(convert, DBTYPE_VARIANT, DBTYPE_R4, 0, &dst_len, &v, &dst, sizeof(dst), 0, &dst_status, 0, 0, 0);
+    ok(hr == S_OK, "got %08x\n", hr);
+    ok(dst_status == DBSTATUS_S_OK, "got %08x\n", dst_status);
+    ok(dst_len == sizeof(dst), "got %ld\n", dst_len);
+    ok(dst == 0x4321, "got %f\n", dst);
 }
 
 static void test_converttor8(void)