The Tcpdump Group git mirrors - libpcap/blob - pcap-util.h

   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-util.h - common code for various files
  22  */
  23
  24 #ifndef pcap_util_h
  25 #define pcap_util_h
  26
  27 #include <pcap/pcap-inttypes.h>
  28 /*
  29  * We use the "receiver-makes-right" approach to byte order;
  30  * because time is at a premium when we are writing the file.
  31  * In other words, the pcap_file_header and pcap_pkthdr,
  32  * records are written in host byte order.
  33  * Note that the bytes of packet data are written out in the order in
  34  * which they were received, so multi-byte fields in packets are not
  35  * written in host byte order, they're written in whatever order the
  36  * sending machine put them in.
  37  *
  38  * We also use this for fixing up packet data headers from a remote
  39  * capture, where the server may have a different byte order from the
  40  * client.
  41  *
  42  * ntoh[ls] aren't sufficient because we might need to swap on a big-endian
  43  * machine (if the file was written in little-end order).
  44  */
  45 #define SWAPLL(y)  ((((uint64_t)(y) & 0xff00000000000000ULL) >> 56) | \
  46                       (((uint64_t)(y) & 0x00ff000000000000ULL) >> 40) | \
  47                       (((uint64_t)(y) & 0x0000ff0000000000ULL) >> 24) | \
  48                       (((uint64_t)(y) & 0x000000ff00000000ULL) >> 8)  | \
  49                       (((uint64_t)(y) & 0x00000000ff000000ULL) << 8)  | \
  50                       (((uint64_t)(y) & 0x0000000000ff0000ULL) << 24) | \
  51                       (((uint64_t)(y) & 0x000000000000ff00ULL) << 40) | \
  52                       (((uint64_t)(y) & 0x00000000000000ffULL) << 56))
  53 #define SWAPLONG(y) \
  54     (((((u_int)(y))&0xff)<<24) | \
  55      ((((u_int)(y))&0xff00)<<8) | \
  56      ((((u_int)(y))&0xff0000)>>8) | \
  57      ((((u_int)(y))>>24)&0xff))
  58 #define SWAPSHORT(y) \
  59      ((u_short)(((((u_int)(y))&0xff)<<8) | \
  60                 ((((u_int)(y))&0xff00)>>8)))
  61
  62 extern void pcapint_post_process(int linktype, int swapped,
  63     struct pcap_pkthdr *hdr, u_char *data);
  64
  65 #endif // pcap_util_h