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+/*
+ * Copyright (c) International Business Machines Corp., 2014
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/*! @file type.h
+ *  @brief Type helpers
+ *  @author Shaun Wetzstein <shaun@us.ibm.com>
+ *  @date 2010-2011
+ */
+
+#ifndef __TYPE_H__
+#define __TYPE_H__
+
+#include "align.h"
+
+/*!
+ * @def cast_type(e,T)
+ * @hideinitializer
+ * @brief Casts @em p to type @em T
+ * @param e [in] Expression
+ * @param T [in] Type name
+ */
+#define cast_type(e,T)						\
+    ((T)(e))
+
+/*!
+ * @def check_type(e,T)
+ * @hideinitializer
+ * @brief Check the type of expression @em e is equal to type @em T
+ * @param e [in] Expression
+ * @param T [in] Type name
+ */
+#define check_type(e,T)						\
+    ((typeof(e) *)0 != (T *)0)
+
+/*!
+ * @def check_types_match(e,T)
+ * @hideinitializer
+ * @brief Check the types of expressions @em e1 and @em e2 are equal
+ * @param e1 [in] Expression
+ * @param e2 [in] Expression
+ */
+#define check_types_match(e1,e2)				\
+    ((typeof(e1) *) 0 != (typeof(e2) *)0)
+
+/*!
+ * @def container_of(member_ptr, containing_type, member)
+ * @hideinitializer
+ * @brief Returns a pointer to the containing structure of a member
+ * @param p [in] Pointer to a strucure member
+ * @param T [in] Type of the containing structure
+ * @param m [in] Name of the member @em p references
+ */
+#define container_of(p,T,m)					\
+    ((T *)((char *)(p) - offsetof(T,m)) - check_types_match(*(p),((T*)0)->m))
+
+/*!
+ * @def container_of_var(member_ptr, var, member)
+ * @hideinitializer
+ * @brief Returns a pointer to the containing structure of a member
+ * @param p [in] Pointer to a strucure member
+ * @param v [in] Pointer to a variable with the same of type as the containing structure
+ * @param m [in] Name of the member @em p references
+ */
+#define container_of_var(p, v, m)				\
+    container_of(p, typeof(*v), m)
+
+#endif				/* __TYPE_H__ */