extract.h

This directory contains source code for tcpdump, a tool for network monitoring and data acquisition

/*
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *      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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * @(#) $Header: extract.h,v 1.14 96/07/15 18:23:12 leres Exp $ (LBL)
 */

/* Network to host order macros
 */
#define EXTRACT_16BITS(p)   ((u_short)ntohs(*(u_short*)(p)))
#define EXTRACT_32BITS(p)   ntohl(*(u_int*)(p))


#define EXTRACT_24BITS(p)   ((u_int)*((u_char*)(p)+0) << 16 | \
                             (u_int)*((u_char*)(p)+1) << 8 |  \
                             (u_int)*((u_char*)(p)+2))

/* Little endian protocol host order macros
 */
#define EXTRACT_LE_8BITS(p)  (*(p))

#define EXTRACT_LE_16BITS(p) ((u_short)*((u_char*)(p)+1) << 8 | \
                              (u_short)*((u_char*)(p)+0))

#define EXTRACT_LE_32BITS(p) ((u_int)*((u_char*)(p)+3) << 24 | \
                              (u_int)*((u_char*)(p)+2) << 16 | \
                              (u_int)*((u_char*)(p)+1) << 8 |  \
                              (u_int)*((u_char*)(p)+0))