x3daudio1_6: Use shared source.

configure

@@ -13719,6 +13719,7 @@ fi
 if test "x$ac_cv_have_openalsoft" != xyes
 then
     as_fn_append wine_notices "|openal-soft ${notice_platform}development files not found (or too old), XAudio2 won't be supported"
+    enable_x3daudio1_6=${enable_x3daudio1_6:-no}
     enable_x3daudio1_7=${enable_x3daudio1_7:-no}
     enable_xapofx1_1=${enable_xapofx1_1:-no}
     enable_xapofx1_2=${enable_xapofx1_2:-no}

configure.ac

@@ -1662,6 +1662,7 @@ fi
 if test "x$ac_cv_have_openalsoft" != xyes
 then
     WINE_NOTICE([openal-soft ${notice_platform}development files not found (or too old), XAudio2 won't be supported])
+    enable_x3daudio1_6=${enable_x3daudio1_6:-no}
     enable_x3daudio1_7=${enable_x3daudio1_7:-no}
     enable_xapofx1_1=${enable_xapofx1_1:-no}
     enable_xapofx1_2=${enable_xapofx1_2:-no}

dlls/x3daudio1_6/Makefile.in

+EXTRADEFS = -DX3DAUDIO1_VER=6 -DXAUDIO2_VER=6
 MODULE    = x3daudio1_6.dll
+PARENTSRC = ../xaudio2_7
 
 C_SRCS = \
-	main.c
+	x3daudio.c

dlls/x3daudio1_6/main.c

-/*
- * Copyright 2015 Austin English
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
- */
-
-#include "config.h"
-
-#include <stdarg.h>
-
-#include "windef.h"
-#include "winbase.h"
-
-#include "x3daudio.h"
-
-BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
-{
-    switch (fdwReason)
-    {
-        case DLL_WINE_PREATTACH:
-            return FALSE;    /* prefer native version */
-        case DLL_PROCESS_ATTACH:
-            DisableThreadLibraryCalls(hinstDLL);
-            break;
-        case DLL_PROCESS_DETACH:
-            break;
-    }
-
-    return TRUE;
-}

dlls/x3daudio1_6/x3daudio1_6.spec

-@ cdecl X3DAudioCalculate(ptr ptr ptr long ptr) xaudio2_8.X3DAudioCalculate
-@ cdecl X3DAudioInitialize(long float ptr) x3daudio1_7.X3DAudioInitialize
+@ cdecl X3DAudioCalculate(ptr ptr ptr long ptr)
+@ cdecl X3DAudioInitialize(long float ptr) LEGACY_X3DAudioInitialize