1 /* 2 * Copyright (c) 1993, 1994, 1995, 1996, 1997 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 * 21 * pcap-common.h - common code for pcap and pcapng files 22 */ 23 24 /* 25 * We use the "receiver-makes-right" approach to byte order, 26 * because time is at a premium when we are writing the file. 27 * In other words, the pcap_file_header and pcap_pkthdr, 28 * records are written in host byte order. 29 * Note that the bytes of packet data are written out in the order in 30 * which they were received, so multi-byte fields in packets are not 31 * written in host byte order, they're written in whatever order the 32 * sending machine put them in. 33 * 34 * ntoh[ls] aren't sufficient because we might need to swap on a big-endian 35 * machine (if the file was written in little-end order). 36 */ 37 #define SWAPLONG(y) \ 38 (((((u_int)(y))&0xff)<<24) | \ 39 ((((u_int)(y))&0xff00)<<8) | \ 40 ((((u_int)(y))&0xff0000)>>8) | \ 41 ((((u_int)(y))>>24)&0xff)) 42 #define SWAPSHORT(y) \ 43 ((u_short)(((((u_int)(y))&0xff)<<8) | \ 44 ((((u_int)(y))&0xff00)>>8))) 45 46 extern int dlt_to_linktype(int dlt); 47 48 extern int linktype_to_dlt(int linktype); 49 50 extern void swap_pseudo_headers(int linktype, struct pcap_pkthdr *hdr, 51 u_char *data); 52 53 extern u_int max_snaplen_for_dlt(int dlt); 54