Initial refactoring of callback macros to make sure all compilers are supported

git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@1812 7f0cb862-5218-0410-a997-914c9d46530a

freeglut/freeglut/CMakeLists.txt

@@ -91,6 +91,7 @@ SET(FREEGLUT_SRCS
     src/fg_init.c
     src/fg_init.h
     src/fg_internal.h
+    src/fg_callback_macros.h
     src/fg_input_devices.c
     src/fg_joystick.c
     src/fg_main.c

freeglut/freeglut/src/fg_callback_macros.h

@@ -0,0 +1,226 @@
+/*
+ * fg_callback_macros.h
+ *
+ * The freeglut library callback macro file.
+ *
+ * Copyright (c) 1999-2000 Pawel W. Olszta. All Rights Reserved.
+ * Written by Pawel W. Olszta, <olszta@sourceforge.net>
+ * Creation date: Thu Dec 2 1999
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * PAWEL W. OLSZTA BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef FREEGLUT_CALLBACK_MACROS_H
+#define FREEGLUT_CALLBACK_MACROS_H
+
+#ifndef FREEGLUT_INTERNAL_H
+#error "fg_internal.h needs to be included before this header"
+#endif
+
+#if 0 /* old. Remove once other testing is complete */
+/*
+ * EXPAND_WCB() is used as:
+ * 
+ *     EXPAND_WCB arg_list
+ * 
+ * ... where {(arg_list)} is the parameter list.
+ *
+ * This will take the arg_list and extend it by one argument, adding
+ * the argument "userData" to the end of the list.
+ * 
+ * All additional args are to get around trailing ',', argument counts,
+ * and not needing a GCC extension to make this work.
+ *
+ * Minor modification of:
+ * http://stackoverflow.com/questions/5355241/generating-function-declaration-using-a-macro-iteration/5355946#5355946
+ *
+ * Supports up to five arguments
+ */
+
+/* GCC-specific design that doesn't require per-callback defines */
+
+#define PP_HAS_ARGS_IMPL2(_0, _1, _2, _3, _4, _5, N, ...) N
+#define PP_HAS_ARGS_SOURCE() \
+    ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ZERO
+
+#define PP_HAS_ARGS_IMPL(...) \
+    PP_HAS_ARGS_IMPL2(__VA_ARGS__)
+#define PP_HAS_ARGS(...) \
+    PP_HAS_ARGS_IMPL(NOT_EXIST, ##__VA_ARGS__, PP_HAS_ARGS_SOURCE())
+
+#define EXPAND_WCB_ZERO(x) \
+    (userData)
+#define EXPAND_WCB_ONE_OR_MORE(...) \
+    (__VA_ARGS__, userData)
+
+#define EXPAND_WCB_DISAMBIGUATE2(has_args, ...) \
+    EXPAND_WCB_ ## has_args (__VA_ARGS__)
+#define EXPAND_WCB_DISAMBIGUATE(has_args, ...) \
+    EXPAND_WCB_DISAMBIGUATE2(has_args, __VA_ARGS__)
+#define EXPAND_WCB(...) \
+    EXPAND_WCB_DISAMBIGUATE(PP_HAS_ARGS(__VA_ARGS__), __VA_ARGS__)
+#endif
+
+/*
+ * Compiler defines:
+ * FG_COMPILER_SUPPORTS_GCC_VA_ARGS_HACK: if the compiler supports GCC's varadic macro implementation (AKA, ##__VA_ARGS__)
+ * FG_COMPILER_SUPPORTS_VA_ARGS: if the compiler supports varadic macros
+ */
+
+#ifdef FG_COMPILER_SUPPORTS_GCC_VA_ARGS_HACK
+
+ /*
+ * EXPAND_WCB() is used as:
+ *
+ *     EXPAND_WCB arg_list
+ *
+ * ... where {(arg_list)} is the parameter list.
+ *
+ * This will take the arg_list and extend it by one argument, adding
+ * the argument "userData" to the end of the list.
+ *
+ * All additional args are to get around trailing ',', argument counts,
+ * and not needing a GCC extension to make this work.
+ *
+ * Modification of:
+ * http://stackoverflow.com/questions/5355241/generating-function-declaration-using-a-macro-iteration/5355946#5355946
+ *
+ * --------------
+ *
+ * GCC-specific design that doesn't require per-callback defines
+ *
+ * The naming is terrible... and it's very convuluted and complex, but
+ * should not require any modification unless additional arguments are to 
+ * be supported.
+ * 
+ * Supports callbacks up to 5 args (follow the pattern of PP_HAS_ARGS_IMPL2
+ * and PP_HAS_ARGS_SOURCE to add more)
+ *
+ * Edit with care.
+ */
+
+#define EXPAND_WCB_UNPARAN(...) __VA_ARGS__
+
+#define PP_HAS_ARGS_IMPL2(_0, _1, _2, _3, _4, _5, N, ...) N
+#define PP_HAS_ARGS_SOURCE() ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ZERO
+
+#define PP_HAS_ARGS_IMPL(...) PP_HAS_ARGS_IMPL2( __VA_ARGS__ )
+#define PP_HAS_ARGS(...) PP_HAS_ARGS_IMPL( NOT_EXIST, ##__VA_ARGS__, PP_HAS_ARGS_SOURCE() )
+
+#define EXPAND_WCB_ZERO(args, userData) ( userData )
+#define EXPAND_WCB_ONE_OR_MORE(args, userData) ( EXPAND_WCB_UNPARAN args, userData )
+
+#define EXPAND_WCB_DISAMBIGUATE(has_args, args, userData) EXPAND_WCB_ ## has_args ( args, userData )
+
+#define EXPAND_WCB_UNWRAP_ARGS2(args, userData) EXPAND_WCB_DISAMBIGUATE( PP_HAS_ARGS args, args, userData )
+#define EXPAND_WCB_UNWRAP_ARGS(args) EXPAND_WCB_UNWRAP_ARGS2 args
+
+#define EXPAND_WCB(cbname) EXPAND_WCB_UNWRAP_ARGS
+
+#else
+
+/*
+ * EXPAND_WCB() is used as:
+ * 
+ *     EXPAND_WCB( cbname )(( arg_list, userData ))
+ * 
+ * ... where {(arg_list)} is the parameter list and userData is user
+ * provided data.
+ *
+ * This will take the arg_list and extend it by one argument, adding
+ * the argument "userData" to the end of the list.
+ *
+ * In order for this to work, each callback must have a define that
+ * properly handles the arguments as needed by the callback.
+ * This callback is in the format of EXPAND_WCB_SUB_<cbname>.
+ * Helper functions exist for zero to five parameters: EXPAND_WCB_ZERO,
+ * EXPAND_WCB_ONE, EXPAND_WCB_TWO, EXPAND_WCB_THREE< EXPAND_WCB_FOUR,
+ * and EXPAND_WCB_FIVE. Each handle the callback argument counts.
+ *
+ * An example for the "Entry" callback, where "Entry" is the cbname:
+ * typedef void (* FGCBEntry  )( int );
+ * typedef void (* FGCBEntryUC)( int, FGCBUserData );
+ * #define EXPAND_WCB_SUB_Entry(args) EXPAND_WCB_ONE args
+ */
+
+#define FG_COMPILER_SUPPORTS_VA_ARGS //XXX (should be compiler defined)
+#ifdef FG_COMPILER_SUPPORTS_VA_ARGS
+
+#define EXPAND_WCB_UNPARAN(...) __VA_ARGS__
+#define EXPAND_WCB_ONE_OR_MORE(args, userData) ( EXPAND_WCB_UNPARAN args, userData )
+
+#define EXPAND_WCB_ONE(args, userData) EXPAND_WCB_ONE_OR_MORE( args, userData )
+#define EXPAND_WCB_TWO(args, userData) EXPAND_WCB_ONE_OR_MORE( args, userData )
+#define EXPAND_WCB_THREE(args, userData) EXPAND_WCB_ONE_OR_MORE( args, userData )
+#define EXPAND_WCB_FOUR(args, userData) EXPAND_WCB_ONE_OR_MORE( args, userData )
+#define EXPAND_WCB_FIVE(args, userData) EXPAND_WCB_ONE_OR_MORE( args, userData )
+
+#else
+
+//TODO
+#error "Compiler does not support varadic argument macros"
+
+#endif
+
+#define EXPAND_WCB_ZERO(args, userData) ( userData )
+
+#define EXPAND_WCB(cbname) EXPAND_WCB_SUB_ ## cbname
+
+/* 
+ * Freeglut callbacks type definitions macros
+ *
+ * Every time a callback is updated in fg_internal.h is updated, this needs updated
+ * if argument counts change, new callbacks are added, or callbacks are removed.
+ */
+
+#define EXPAND_WCB_SUB_Display(args) EXPAND_WCB_ZERO args
+#define EXPAND_WCB_SUB_Reshape(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_Position(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_Visibility(args) EXPAND_WCB_ONE args
+#define EXPAND_WCB_SUB_Keyboard(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_KeyboardUp(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_Special(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_SpecialUp(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_Mouse(args) EXPAND_WCB_FOUR args
+#define EXPAND_WCB_SUB_MouseWheel(args) EXPAND_WCB_FOUR args
+#define EXPAND_WCB_SUB_Motion(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_Passive(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_Entry(args) EXPAND_WCB_ONE args
+#define EXPAND_WCB_SUB_WindowStatus(args) EXPAND_WCB_ONE args
+#define EXPAND_WCB_SUB_Joystick(args) EXPAND_WCB_FOUR args
+#define EXPAND_WCB_SUB_OverlayDisplay(args) EXPAND_WCB_ZERO args
+#define EXPAND_WCB_SUB_SpaceMotion(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_SpaceRotation(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_SpaceButton(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_Dials(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_ButtonBox(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_TabletMotion(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_TabletButton(args) EXPAND_WCB_FOUR args
+#define EXPAND_WCB_SUB_Destroy(args) EXPAND_WCB_ZERO args
+#define EXPAND_WCB_SUB_MultiEntry(args) EXPAND_WCB_TWO args
+#define EXPAND_WCB_SUB_MultiButton(args) EXPAND_WCB_FIVE args
+#define EXPAND_WCB_SUB_MultiMotion(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_MultiPassive(args) EXPAND_WCB_THREE args
+#define EXPAND_WCB_SUB_InitContext(args) EXPAND_WCB_ZERO args
+#define EXPAND_WCB_SUB_AppStatus(args) EXPAND_WCB_ONE args
+
+#endif
+
+#endif /* FREEGLUT_CALLBACK_MACROS_H */
+
+/*** END OF FILE ***/

freeglut/freeglut/src/fg_internal.h

@@ -33,12 +33,14 @@
 #endif
 
 #include "fg_version.h"
+#include "fg_callback_macros.h"
 
 /* Freeglut is intended to function under all Unix/X11 and Win32 platforms. */
 /* XXX: Don't all MS-Windows compilers (except Cygwin) have _WIN32 defined?
  * XXX: If so, remove the first set of defined()'s below.
  */
-#if !defined(TARGET_HOST_POSIX_X11) && !defined(TARGET_HOST_MS_WINDOWS) && !defined(TARGET_HOST_MAC_OSX) && !defined(TARGET_HOST_SOLARIS)
+#if !defined(TARGET_HOST_POSIX_X11) && !defined(TARGET_HOST_MS_WINDOWS) && !defined(TARGET_HOST_MAC_OSX) && !defined(TARGET_HOST_SOLARIS) && \
+    !defined(TARGET_HOST_ANDROID) && !defined(TARGET_HOST_BLACKBERRY) && !defined(TARGET_HOST_POSIX_WAYLAND)
 #if defined(_MSC_VER) || defined(__WATCOMC__) || defined(__MINGW32__) \
     || defined(_WIN32) || defined(_WIN32_WCE) \
     || ( defined(__CYGWIN__) && defined(X_DISPLAY_MISSING) )
@@ -215,101 +217,78 @@
 
 /* -- GLOBAL TYPE DEFINITIONS ---------------------------------------------- */
 
-/* Freeglut callbacks type definitions */
+/* 
+ * Freeglut callbacks type definitions
+ *
+ * If anything here is modified or added, update fg_callback_macros.h functions.
+ *
+ * This is not ideal, but freeglut needs to either define minimal compiler specs,
+ * or update header every time this is changed or updated.
+ */
 typedef void* FGCBUserData;
 
 typedef void (* FGCBDisplay         )( void );
 typedef void (* FGCBDisplayUC       )( FGCBUserData );
-#define EXPAND_WCB_SUB_Display(args, userData) EXPAND_WCB_ZERO(args, userData)
 typedef void (* FGCBReshape         )( int, int );
 typedef void (* FGCBReshapeUC       )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Reshape(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBPosition        )( int, int );
 typedef void (* FGCBPositionUC      )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Position(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBVisibility      )( int );
 typedef void (* FGCBVisibilityUC    )( int, FGCBUserData );
-#define EXPAND_WCB_SUB_Visibility(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBKeyboard        )( unsigned char, int, int );
 typedef void (* FGCBKeyboardUC      )( unsigned char, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Keyboard(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBKeyboardUp      )( unsigned char, int, int );
 typedef void (* FGCBKeyboardUpUC    )( unsigned char, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_KeyboardUp(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBSpecial         )( int, int, int );
 typedef void (* FGCBSpecialUC       )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Special(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBSpecialUp       )( int, int, int );
 typedef void (* FGCBSpecialUpUC     )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_SpecialUp(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMouse           )( int, int, int, int );
 typedef void (* FGCBMouseUC         )( int, int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Mouse(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMouseWheel      )( int, int, int, int );
 typedef void (* FGCBMouseWheelUC    )( int, int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_MouseWheel(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMotion          )( int, int );
 typedef void (* FGCBMotionUC        )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Motion(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBPassive         )( int, int );
 typedef void (* FGCBPassiveUC       )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Passive(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBEntry           )( int );
 typedef void (* FGCBEntryUC         )( int, FGCBUserData );
-#define EXPAND_WCB_SUB_Entry(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBWindowStatus    )( int );
 typedef void (* FGCBWindowStatusUC  )( int, FGCBUserData );
-#define EXPAND_WCB_SUB_WindowStatus(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBJoystick        )( unsigned int, int, int, int );
 typedef void (* FGCBJoystickUC      )( unsigned int, int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Joystick(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBOverlayDisplay  )( void );
 typedef void (* FGCBOverlayDisplayUC)( FGCBUserData );
-#define EXPAND_WCB_SUB_OverlayDisplay(args, userData) EXPAND_WCB_ZERO(args, userData)
 typedef void (* FGCBSpaceMotion     )( int, int, int );
 typedef void (* FGCBSpaceMotionUC   )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_SpaceMotion(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBSpaceRotation   )( int, int, int );
 typedef void (* FGCBSpaceRotationUC )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_SpaceRotation(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBSpaceButton     )( int, int );
 typedef void (* FGCBSpaceButtonUC   )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_SpaceButton(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBDials           )( int, int );
 typedef void (* FGCBDialsUC         )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_Dials(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBButtonBox       )( int, int );
 typedef void (* FGCBButtonBoxUC     )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_ButtonBox(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBTabletMotion    )( int, int );
 typedef void (* FGCBTabletMotionUC  )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_TabletMotion(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBTabletButton    )( int, int, int, int );
 typedef void (* FGCBTabletButtonUC  )( int, int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_TabletButton(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBDestroy         )( void );    /* Used for both window and menu destroy callbacks */
 typedef void (* FGCBDestroyUC       )( FGCBUserData );
-#define EXPAND_WCB_SUB_Destroy(args, userData) EXPAND_WCB_ZERO(args, userData)
 
 typedef void (* FGCBMultiEntry      )( int, int );
 typedef void (* FGCBMultiEntryUC    )( int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_MultiEntry(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMultiButton     )( int, int, int, int, int );
 typedef void (* FGCBMultiButtonUC   )( int, int, int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_MultiButton(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMultiMotion     )( int, int, int );
 typedef void (* FGCBMultiMotionUC   )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_MultiMotion(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 typedef void (* FGCBMultiPassive    )( int, int, int );
 typedef void (* FGCBMultiPassiveUC  )( int, int, int, FGCBUserData );
-#define EXPAND_WCB_SUB_MultiPassive(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 
 typedef void (* FGCBInitContext     )( void );
 typedef void (* FGCBInitContextUC   )( FGCBUserData );
-#define EXPAND_WCB_SUB_InitContext(args, userData) EXPAND_WCB_ZERO(args, userData)
 typedef void (* FGCBAppStatus       )( int );
 typedef void (* FGCBAppStatusUC     )( int, FGCBUserData );
-#define EXPAND_WCB_SUB_AppStatus(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
 
 /* The global callbacks type definitions */
 typedef void (* FGCBIdle            )( void ); \
@@ -646,54 +625,10 @@ do                                                             \
 #define FETCH_USER_DATA_WCB(window,cbname) \
     ((window).CallbackDatas[WCB_ ## cbname])
 
-#if 0
 /*
  * EXPAND_WCB() is used as:
  * 
- *     EXPAND_WCB arg_list
+ *     EXPAND_WCB( cbname )(( arg_list, userData ))
- * 
- * ... where {(arg_list)} is the parameter list.
- *
- * This will take the arg_list and extend it by one argument, adding
- * the argument "userData" to the end of the list.
- * 
- * All additional args are to get around trailing ',', argument counts,
- * and not needing a GCC extension to make this work.
- *
- * Minor modification of:
- * http://stackoverflow.com/questions/5355241/generating-function-declaration-using-a-macro-iteration/5355946#5355946
- *
- * Supports up to five arguments
- */
-
-/* GCC-specific design that doesn't require per-callback defines */
-
-#define PP_HAS_ARGS_IMPL2(_0, _1, _2, _3, _4, _5, N, ...) N
-#define PP_HAS_ARGS_SOURCE() \
-    ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ONE_OR_MORE, ZERO
-
-#define PP_HAS_ARGS_IMPL(...) \
-    PP_HAS_ARGS_IMPL2(__VA_ARGS__)
-#define PP_HAS_ARGS(...) \
-    PP_HAS_ARGS_IMPL(NOT_EXIST, ##__VA_ARGS__, PP_HAS_ARGS_SOURCE())
-
-#define EXPAND_WCB_ZERO(x) \
-    (userData)
-#define EXPAND_WCB_ONE_OR_MORE(...) \
-    (__VA_ARGS__, userData)
-
-#define EXPAND_WCB_DISAMBIGUATE2(has_args, ...) \
-    EXPAND_WCB_ ## has_args (__VA_ARGS__)
-#define EXPAND_WCB_DISAMBIGUATE(has_args, ...) \
-    EXPAND_WCB_DISAMBIGUATE2(has_args, __VA_ARGS__)
-#define EXPAND_WCB(...) \
-    EXPAND_WCB_DISAMBIGUATE(PP_HAS_ARGS(__VA_ARGS__), __VA_ARGS__)
-
-#else
-/*
- * EXPAND_WCB() is used as:
- * 
- *     EXPAND_WCB( cbname )( arg_list, userData )
  * 
  * ... where {(arg_list)} is the parameter list and userData is user
  * provided data.
@@ -701,30 +636,12 @@ do                                                             \
  * This will take the arg_list and extend it by one argument, adding
  * the argument "userData" to the end of the list.
  *
- * In order for this to work, each callback must have a define that
+ * All of this is defined in fg_callback_macros.h
- * properly handles the arguments as needed by the callback.
- * This callback is in the format of EXPAND_WCB_SUB_<cbname>.
- * Two helper defines exist: EXPAND_WCB_ZERO and EXPAND_WCB_ONE_OR_MORE,
- * each to handle callbacks that take zero-params (but take userData) and
- * to take one or more params (along with userData).
  *
- * An example for the "Entry" callback, where "Entry" is the cbname:
+ * See that header for more info.
- * typedef void (* FGCBEntry  )( int );
+ *
- * typedef void (* FGCBEntryUC)( int, FGCBUserData );
+ * ------------------------------------------------------------------
- * #define EXPAND_WCB_SUB_Entry(args, userData) EXPAND_WCB_ONE_OR_MORE(args, userData)
  */
-#define FG_COMPILER_SUPPORTS_VA_ARGS
-#ifdef FG_COMPILER_SUPPORTS_VA_ARGS
-#define EXPAND_WCB_UNPARAN(...) __VA_ARGS__
-#else
-#error "Compiler does not support varadic argument macros"
-#endif
-
-#define EXPAND_WCB_ZERO(args, userData) ( userData )
-#define EXPAND_WCB_ONE_OR_MORE(args, userData) ( EXPAND_WCB_UNPARAN args, userData )
-
-#define EXPAND_WCB(cbname) EXPAND_WCB_SUB_ ## cbname
-#endif
 
 /*
  * INVOKE_WCB() is used as:
@@ -755,7 +672,7 @@ do                                            \
         FGCB ## cbname ## UC func = (FGCB ## cbname ## UC)(FETCH_WCB( window, cbname )); \
         FGCBUserData userData = FETCH_USER_DATA_WCB( window, cbname ); \
         fgSetWindow( &window );               \
-		func EXPAND_WCB( cbname )( arg_list, userData ); \
+		func EXPAND_WCB( cbname )(( arg_list, userData )); \
     }                                         \
 } while( 0 )
 #else
@@ -766,7 +683,7 @@ do                                            \
     {                                         \
         fgSetWindow( &window );               \
         FGCBUserData userData = FETCH_USER_DATA_WCB( window, cbname ); \
-		((FGCB ## cbname ## UC)FETCH_WCB( window, cbname )) EXPAND_WCB( cbname )( arg_list, userData ); \
+		((FGCB ## cbname ## UC)FETCH_WCB( window, cbname )) EXPAND_WCB( cbname )(( arg_list, userData )); \
     }                                         \
 } while( 0 )
 #endif