-/* struct.h 4.1 83/05/03 */
-
-/*
- * access to information relating to the fields of a structure
+/*-
+ * Copyright (c) 1983 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)struct.h 5.2 (Berkeley) 4/3/91
*/
-#define fldoff(str, fld) ((int)&(((struct str *)0)->fld))
-#define fldsiz(str, fld) (sizeof(((struct str *)0)->fld))
-#define strbase(str, ptr, fld) ((struct str *)((char *)(ptr)-fldoff(str, fld)))
+#ifndef _STRUCT_H_
+#define _STRUCT_H_
+
+/* Offset of the field in the structure. */
+#define fldoff(name, field) \
+ ((int)&(((struct name *)0)->field))
+
+/* Size of the field in the structure. */
+#define fldsiz(name, field) \
+ (sizeof(((struct name *)0)->field))
+
+/* Address of the structure from a field. */
+#define strbase(name, addr, field) \
+ ((struct name *)((char *)(addr) - fldoff(name, field)))
+
+#endif /* !_STRUCT_H_ */