shared: make NM_CONSTCAST() macro variadic

We need to pass more alias-types. Instead of having numbered
versions, use variadic number of macro arguments.

Also, fix build failure with old compiler:

  In file included from src/nm-ip6-config.c:24:
  ./src/nm-ip6-config.h:44:29: error: controlling expression type 'typeof (ipconf_iter->current->obj)' (aka 'const void *const') not compatible with any generic association type
                  *out_address = has_next ? NMP_OBJECT_CAST_IP6_ADDRESS (ipconf_iter->current->obj) : NULL;
                                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: b1810d7a68d188aa8f36a0e23a7be705a742b1aa

4 files changed, 86 insertions, 57 deletions

diff --git a/shared/nm-utils/nm-macros-internal.h b/shared/nm-utils/nm-macros-internal.h
index 68b69bf403..d07e298ea2 100644
--- a/shared/nm-utils/nm-macros-internal.h
+++ b/shared/nm-utils/nm-macros-internal.h
@@ -270,63 +270,94 @@ NM_G_ERROR_MSG (GError *error)
 #endif
 
 #if _NM_CC_SUPPORT_GENERIC
-#define _NM_CONSTCAST_FULL(type, obj_expr, obj) \
+#define _NM_CONSTCAST_FULL_1(type, obj_expr, obj) \
 	(_Generic ((obj_expr), \
-	           const void *     : ((const type *) (obj)), \
-	           void *           : ((      type *) (obj)), \
-	           const type *     : ((const type *) (obj)), \
-	           type *           : ((      type *) (obj))))
-#define _NM_CONSTCAST2_FULL(type, obj_expr, obj, alias_type2) \
+	           const void        *const: ((const type *) (obj)), \
+	           const void        *     : ((const type *) (obj)), \
+	                 void        *const: ((      type *) (obj)), \
+	                 void        *     : ((      type *) (obj)), \
+	           const type        *const: ((const type *) (obj)), \
+	           const type        *     : ((const type *) (obj)), \
+	                 type        *const: ((      type *) (obj)), \
+	                 type        *     : ((      type *) (obj))))
+#define _NM_CONSTCAST_FULL_2(type, obj_expr, obj, alias_type2) \
 	(_Generic ((obj_expr), \
-	           const void        *: ((const type *) (obj)), \
-	                 void        *: ((      type *) (obj)), \
-	           const alias_type2 *: ((const type *) (obj)), \
-	                 alias_type2 *: ((      type *) (obj)), \
-	           const type        *: ((const type *) (obj)), \
-	                 type        *: ((      type *) (obj))))
-#define _NM_CONSTCAST3_FULL(type, obj_expr, obj, alias_type2, alias_type3) \
+	           const void        *const: ((const type *) (obj)), \
+	           const void        *     : ((const type *) (obj)), \
+	                 void        *const: ((      type *) (obj)), \
+	                 void        *     : ((      type *) (obj)), \
+	           const alias_type2 *const: ((const type *) (obj)), \
+	           const alias_type2 *     : ((const type *) (obj)), \
+	                 alias_type2 *const: ((      type *) (obj)), \
+	                 alias_type2 *     : ((      type *) (obj)), \
+	           const type        *const: ((const type *) (obj)), \
+	           const type        *     : ((const type *) (obj)), \
+	                 type        *const: ((      type *) (obj)), \
+	                 type        *     : ((      type *) (obj))))
+#define _NM_CONSTCAST_FULL_3(type, obj_expr, obj, alias_type2, alias_type3) \
 	(_Generic ((obj_expr), \
-	           const void        *: ((const type *) (obj)), \
-	                 void        *: ((      type *) (obj)), \
-	           const alias_type2 *: ((const type *) (obj)), \
-	                 alias_type2 *: ((      type *) (obj)), \
-	           const alias_type3 *: ((const type *) (obj)), \
-	                 alias_type3 *: ((      type *) (obj)), \
-	           const type        *: ((const type *) (obj)), \
-	                 type        *: ((      type *) (obj))))
+	           const void        *const: ((const type *) (obj)), \
+	           const void        *     : ((const type *) (obj)), \
+	                 void        *const: ((      type *) (obj)), \
+	                 void        *     : ((      type *) (obj)), \
+	           const alias_type2 *const: ((const type *) (obj)), \
+	           const alias_type2 *     : ((const type *) (obj)), \
+	                 alias_type2 *const: ((      type *) (obj)), \
+	                 alias_type2 *     : ((      type *) (obj)), \
+	           const alias_type3 *const: ((const type *) (obj)), \
+	           const alias_type3 *     : ((const type *) (obj)), \
+	                 alias_type3 *const: ((      type *) (obj)), \
+	                 alias_type3 *     : ((      type *) (obj)), \
+	           const type        *const: ((const type *) (obj)), \
+	           const type        *     : ((const type *) (obj)), \
+	                 type        *const: ((      type *) (obj)), \
+	                 type        *     : ((      type *) (obj))))
+#define _NM_CONSTCAST_FULL_4(type, obj_expr, obj, alias_type2, alias_type3, alias_type4) \
+	(_Generic ((obj_expr), \
+	           const void        *const: ((const type *) (obj)), \
+	           const void        *     : ((const type *) (obj)), \
+	                 void        *const: ((      type *) (obj)), \
+	                 void        *     : ((      type *) (obj)), \
+	           const alias_type2 *const: ((const type *) (obj)), \
+	           const alias_type2 *     : ((const type *) (obj)), \
+	                 alias_type2 *const: ((      type *) (obj)), \
+	                 alias_type2 *     : ((      type *) (obj)), \
+	           const alias_type3 *const: ((const type *) (obj)), \
+	           const alias_type3 *     : ((const type *) (obj)), \
+	                 alias_type3 *const: ((      type *) (obj)), \
+	                 alias_type3 *     : ((      type *) (obj)), \
+	           const alias_type4 *const: ((const type *) (obj)), \
+	           const alias_type4 *     : ((const type *) (obj)), \
+	                 alias_type4 *const: ((      type *) (obj)), \
+	                 alias_type4 *     : ((      type *) (obj)), \
+	           const type        *const: ((const type *) (obj)), \
+	           const type        *     : ((const type *) (obj)), \
+	                 type        *const: ((      type *) (obj)), \
+	                 type        *     : ((      type *) (obj))))
+#define _NM_CONSTCAST_FULL_x(type, obj_expr, obj, n, ...)   (_NM_CONSTCAST_FULL_##n (type, obj_expr, obj,                        ##__VA_ARGS__))
+#define _NM_CONSTCAST_FULL_y(type, obj_expr, obj, n, ...)   (_NM_CONSTCAST_FULL_x   (type, obj_expr, obj, n,                     ##__VA_ARGS__))
+#define NM_CONSTCAST_FULL(   type, obj_expr, obj,    ...)   (_NM_CONSTCAST_FULL_y   (type, obj_expr, obj, NM_NARG (dummy, ##__VA_ARGS__), ##__VA_ARGS__))
 #else
-/* _NM_CONSTCAST() is there to preserve constness of a pointer.
- * It uses C11's _Generic(). If that is not supported, we fall back
- * to casting away constness. So, with _Generic, we get some additional
- * static type checking by preserving constness, without, we cast it
- * to a non-const pointer. */
-#define _NM_CONSTCAST_FULL(type, obj_expr, obj) \
-	((type *) (obj))
-#define _NM_CONSTCAST2_FULL(type, obj_expr, obj, alias_type2) \
-	((type *) (obj))
-#define _NM_CONSTCAST3_FULL(type, obj_expr, obj, alias_type2, alias_type2) \
-	((type *) (obj))
+#define NM_CONSTCAST_FULL(   type, obj_expr, obj,    ...)   ((type *) (obj))
 #endif
 
-#define _NM_CONSTCAST(type, obj) \
-	_NM_CONSTCAST_FULL(type, (obj), (obj))
-
-#define _NM_CONSTCAST2(type, obj, alias_type2) \
-	_NM_CONSTCAST2_FULL(type, (obj), (obj), alias_type2)
+#define NM_CONSTCAST(type, obj, ...) \
+	NM_CONSTCAST_FULL(type, (obj), (obj), ##__VA_ARGS__)
 
-#define _NM_GOBJECT_CAST(type, obj, is_check) \
+#define NM_GOBJECT_CAST(type, obj, is_check, ...) \
 	({ \
 		const void *_obj = (obj); \
 		\
-		nm_assert (is_check (_obj)); \
-		_NM_CONSTCAST2_FULL (type, (obj), _obj, GObject); \
+		nm_assert (_obj || (is_check (_obj))); \
+		NM_CONSTCAST_FULL (type, (obj), _obj, GObject, ##__VA_ARGS__); \
 	})
-#define _NM_GOBJECT_CAST2(type, obj, is_check, alias_type2) \
+
+#define NM_GOBJECT_CAST_NON_NULL(type, obj, is_check, ...) \
 	({ \
 		const void *_obj = (obj); \
 		\
 		nm_assert (is_check (_obj)); \
-		_NM_CONSTCAST3_FULL (type, (obj), _obj, GObject, alias_type2); \
+		NM_CONSTCAST_FULL (type, (obj), _obj, GObject, ##__VA_ARGS__); \
 	})
 
 #if _NM_CC_SUPPORT_GENERIC
@@ -620,10 +651,8 @@ _notify (obj_type *obj, _PropertyEnums prop) \
 
 /*****************************************************************************/
 
-#define _NM_GET_PRIVATE(     self, type, is_check)               (&(_NM_GOBJECT_CAST  (type, (self), is_check             )->_priv))
-#define _NM_GET_PRIVATE_PTR( self, type, is_check)               ( (_NM_GOBJECT_CAST  (type, (self), is_check             )->_priv))
-#define _NM_GET_PRIVATE2(    self, type, is_check, alias_type2)  (&(_NM_GOBJECT_CAST2 (type, (self), is_check, alias_type2)->_priv))
-#define _NM_GET_PRIVATE2_PTR(self, type, is_check, alias_type2)  ( (_NM_GOBJECT_CAST2 (type, (self), is_check, alias_type2)->_priv))
+#define _NM_GET_PRIVATE(     self, type, is_check, ...)     (&(NM_GOBJECT_CAST_NON_NULL (type, (self), is_check, ##__VA_ARGS__)->_priv))
+#define _NM_GET_PRIVATE_PTR( self, type, is_check, ...)     ( (NM_GOBJECT_CAST_NON_NULL (type, (self), is_check, ##__VA_ARGS__)->_priv))
 
 /*****************************************************************************/
 
diff --git a/src/devices/nm-device-vlan.c b/src/devices/nm-device-vlan.c
index 1253a66418..81512335c7 100644
--- a/src/devices/nm-device-vlan.c
+++ b/src/devices/nm-device-vlan.c
@@ -66,7 +66,7 @@ struct _NMDeviceVlanClass {
 
 G_DEFINE_TYPE (NMDeviceVlan, nm_device_vlan, NM_TYPE_DEVICE)
 
-#define NM_DEVICE_VLAN_GET_PRIVATE(self) _NM_GET_PRIVATE2 (self, NMDeviceVlan, NM_IS_DEVICE_VLAN, NMDevice)
+#define NM_DEVICE_VLAN_GET_PRIVATE(self) _NM_GET_PRIVATE (self, NMDeviceVlan, NM_IS_DEVICE_VLAN, NMDevice)
 
 /*****************************************************************************/
 
diff --git a/src/platform/nm-linux-platform.c b/src/platform/nm-linux-platform.c
index 9ce520bdcc..9efdd41327 100644
--- a/src/platform/nm-linux-platform.c
+++ b/src/platform/nm-linux-platform.c
@@ -2867,7 +2867,7 @@ struct _NMLinuxPlatformClass {
 
 G_DEFINE_TYPE (NMLinuxPlatform, nm_linux_platform, NM_TYPE_PLATFORM)
 
-#define NM_LINUX_PLATFORM_GET_PRIVATE(self) _NM_GET_PRIVATE2(self, NMLinuxPlatform, NM_IS_LINUX_PLATFORM, NMPlatform)
+#define NM_LINUX_PLATFORM_GET_PRIVATE(self) _NM_GET_PRIVATE (self, NMLinuxPlatform, NM_IS_LINUX_PLATFORM, NMPlatform)
 
 NMPlatform *
 nm_linux_platform_new (gboolean log_with_ptr, gboolean netns_support)
diff --git a/src/platform/nmp-object.h b/src/platform/nmp-object.h
index 41fd08cb7c..6db7573a99 100644
--- a/src/platform/nmp-object.h
+++ b/src/platform/nmp-object.h
@@ -341,7 +341,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NMP_OBJECT_GET_TYPE ((const NMPObject *) _obj) == NMP_OBJECT_TYPE_LINK); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->link : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->link : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP_ADDRESS(obj) \
@@ -349,7 +349,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NM_IN_SET (NMP_OBJECT_GET_TYPE (_obj), NMP_OBJECT_TYPE_IP4_ADDRESS, NMP_OBJECT_TYPE_IP6_ADDRESS)); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip_address : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip_address : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IPX_ADDRESS(obj) \
@@ -357,7 +357,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NM_IN_SET (NMP_OBJECT_GET_TYPE (_obj), NMP_OBJECT_TYPE_IP4_ADDRESS, NMP_OBJECT_TYPE_IP6_ADDRESS)); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ipx_address : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ipx_address : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP4_ADDRESS(obj) \
@@ -365,7 +365,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NMP_OBJECT_GET_TYPE ((const NMPObject *) _obj) == NMP_OBJECT_TYPE_IP4_ADDRESS); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip4_address : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip4_address : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP6_ADDRESS(obj) \
@@ -373,7 +373,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NMP_OBJECT_GET_TYPE ((const NMPObject *) _obj) == NMP_OBJECT_TYPE_IP6_ADDRESS); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip6_address : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip6_address : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IPX_ROUTE(obj) \
@@ -381,7 +381,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NM_IN_SET (NMP_OBJECT_GET_TYPE (_obj), NMP_OBJECT_TYPE_IP4_ROUTE, NMP_OBJECT_TYPE_IP6_ROUTE)); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ipx_route : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ipx_route : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP_ROUTE(obj) \
@@ -389,7 +389,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NM_IN_SET (NMP_OBJECT_GET_TYPE (_obj), NMP_OBJECT_TYPE_IP4_ROUTE, NMP_OBJECT_TYPE_IP6_ROUTE)); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip_route : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip_route : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP4_ROUTE(obj) \
@@ -397,7 +397,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NMP_OBJECT_GET_TYPE ((const NMPObject *) _obj) == NMP_OBJECT_TYPE_IP4_ROUTE); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip4_route : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip4_route : NULL; \
 	})
 
 #define NMP_OBJECT_CAST_IP6_ROUTE(obj) \
@@ -405,7 +405,7 @@ NMP_OBJECT_GET_TYPE (const NMPObject *obj)
 		typeof (obj) _obj = (obj); \
 		\
 		nm_assert (!_obj || NMP_OBJECT_GET_TYPE ((const NMPObject *) _obj) == NMP_OBJECT_TYPE_IP6_ROUTE); \
-		_obj ? &_NM_CONSTCAST (NMPObject, _obj)->ip6_route : NULL; \
+		_obj ? &NM_CONSTCAST (NMPObject, _obj)->ip6_route : NULL; \
 	})
 
 const NMPClass *nmp_class_from_type (NMPObjectType obj_type);