contrib/tcpdump/machdep.c

   1 /*
   2  * Copyright (c) 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
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <stddef.h>
  27
  28 #ifdef __osf__
  29 #include <stdio.h>
  30 #include <sys/sysinfo.h>
  31 #include <sys/proc.h>
  32 #endif /* __osf__ */
  33
  34 #include "varattrs.h"
  35 #include "machdep.h"
  36
  37 /*
  38  * On platforms where the CPU doesn't support unaligned loads, force
  39  * unaligned accesses to abort with SIGBUS, rather than being fixed
  40  * up (slowly) by the OS kernel; on those platforms, misaligned accesses
  41  * are bugs, and we want tcpdump to crash so that the bugs are reported.
  42  *
  43  * The only OS on which this is necessary is DEC OSF/1^W^WDigital
  44  * UNIX^W^WTru64 UNIX.
  45  */
  46 int
  47 abort_on_misalignment(char *ebuf _U_, size_t ebufsiz _U_)
  48 {
  49 #ifdef __osf__
  50         static int buf[2] = { SSIN_UACPROC, UAC_SIGBUS };
  51
  52         if (setsysinfo(SSI_NVPAIRS, (caddr_t)buf, 1, 0, 0) < 0) {
  53                 (void)snprintf(ebuf, ebufsiz, "setsysinfo: errno %d", errno);
  54                 return (-1);
  55         }
  56 #endif
  57         return (0);
  58 }