nameser.h

/* Copyright (c) 1983, 1989
 *    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.
 * 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.
 */

/*%
 *      from nameser.h	8.1 (Berkeley) 6/2/93
 *	$BINDId: nameser_compat.h,v 8.11 1999/01/02 08:00:58 vixie Exp $
 */

#ifndef __NAMESER_H__
#define	__NAMESER_H__

/**
 * Structure for query header.  The order of the fields is machine- and
 * compiler-dependent, depending on the byte/bit order and the layout
 * of bit fields.  We use bit fields only in int variables, as this
 * is all ANSI requires.  This requires a somewhat confusing rearrangement.
 */

typedef struct {
	unsigned	id :16;		/*%< query identification number */
#ifdef __BIG_ENDIAN
			/**  fields in third byte */
	unsigned	qr: 1;		/** %< response flag */
	unsigned	opcode: 4;	/** %< purpose of message */
	unsigned	aa: 1;		/** %< authoritive answer */
	unsigned	tc: 1;		/** %< truncated message */
	unsigned	rd: 1;		/** %< recursion desired */
			/**  fields in fourth byte */
	unsigned	ra: 1;		/** %< recursion available */
	unsigned	unused :1;	/** %< unused bits (MBZ as of 4.9.3a3) */
	unsigned	ad: 1;		/** %< authentic data from named */
	unsigned	cd: 1;		/** %< checking disabled by resolver */
	unsigned	rcode :4;	/** %< response code */
#endif
#ifdef __LITTLE_ENDIAN
			/**  fields in third byte */
	unsigned	rd :1;		/** %< recursion desired */
	unsigned	tc :1;		/** %< truncated message */
	unsigned	aa :1;		/** %< authoritive answer */
	unsigned	opcode :4;	/** %< purpose of message */
	unsigned	qr :1;		/** %< response flag */
			/**  fields in fourth byte */
	unsigned	rcode :4;	/** %< response code */
	unsigned	cd: 1;		/** %< checking disabled by resolver */
	unsigned	ad: 1;		/** %< authentic data from named */
	unsigned	unused :1;	/** %< unused bits (MBZ as of 4.9.3a3) */
	unsigned	ra :1;		/** %< recursion available */
#endif
			/**  remaining bytes */
	unsigned	qdcount :16;	/** %< number of question entries */
	unsigned	ancount :16;	/** %< number of answer entries */
	unsigned	nscount :16;	/** %< number of authority entries */
	unsigned	arcount :16;	/** %< number of resource entries */
} HEADER;

#define T_A      1
#define T_CNAME  5
#define T_AAAA  28

#endif /**  __NAMESER_H__ */