db_access.c

Version: - FREEBSD - FREEBSD-13-STABLE - FREEBSD-13-0 - FREEBSD-12-STABLE - FREEBSD-12-0 - FREEBSD-11-STABLE - FREEBSD-11-0 - FREEBSD-10-STABLE - FREEBSD-10-0 - FREEBSD-9-STABLE - FREEBSD-9-0 - FREEBSD-8-STABLE - FREEBSD-8-0 - FREEBSD-7-STABLE - FREEBSD-7-0 - FREEBSD-6-STABLE - FREEBSD-6-0 - FREEBSD-5-STABLE - FREEBSD-5-0 - FREEBSD-4-STABLE - FREEBSD-3-STABLE - FREEBSD22 - l41 - OPENBSD - linux-2.6 - MK84 - PLAN9 - xnu-8792
SearchContext: - none - 3 - 10

    1 /*      $OpenBSD: db_access.c,v 1.16 2019/11/07 13:16:25 mpi Exp $      */
    2 /*      $NetBSD: db_access.c,v 1.8 1994/10/09 08:37:35 mycroft Exp $    */
    3 
    4 /*
    5  * Mach Operating System
    6  * Copyright (c) 1991,1990 Carnegie Mellon University
    7  * All Rights Reserved.
    8  *
    9  * Permission to use, copy, modify and distribute this software and its
   10  * documentation is hereby granted, provided that both the copyright
   11  * notice and this permission notice appear in all copies of the
   12  * software, derivative works or modified versions, and any portions
   13  * thereof, and that both notices appear in supporting documentation.
   14  *
   15  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
   16  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
   17  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   18  *
   19  * Carnegie Mellon requests users of this software to return to
   20  *
   21  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   22  *  School of Computer Science
   23  *  Carnegie Mellon University
   24  *  Pittsburgh PA 15213-3890
   25  *
   26  * any improvements or extensions that they make and grant Carnegie the
   27  * the rights to redistribute these changes.
   28  *
   29  *      Author: David B. Golub, Carnegie Mellon University
   30  *      Date:   7/90
   31  */
   32 
   33 #include <sys/param.h>
   34 #include <sys/endian.h>
   35 
   36 #include <machine/db_machdep.h>         /* type definitions */
   37 
   38 #include <ddb/db_access.h>
   39 
   40 /*
   41  * Access unaligned data items on aligned (longword)
   42  * boundaries.
   43  */
   44 db_expr_t
   45 db_get_value(vaddr_t addr, size_t size, int is_signed)
   46 {
   47         char data[sizeof(db_expr_t)];
   48         db_expr_t value, extend;
   49         int i;
   50 
   51 #ifdef DIAGNOSTIC
   52         if (size > sizeof data)
   53                 size = sizeof data;
   54 #endif
   55 
   56         db_read_bytes(addr, size, data);
   57 
   58         value = 0;
   59         extend = (~(db_expr_t)0) << (size * 8 - 1);
   60 #if BYTE_ORDER == LITTLE_ENDIAN
   61         for (i = size - 1; i >= 0; i--)
   62 #else /* BYTE_ORDER == BIG_ENDIAN */
   63         for (i = 0; i < size; i++)
   64 #endif /* BYTE_ORDER */
   65                 value = (value << 8) + (data[i] & 0xFF);
   66 
   67         if (size < sizeof(db_expr_t) && is_signed && (value & extend))
   68                 value |= extend;
   69         return (value);
   70 }
   71 
   72 void
   73 db_put_value(vaddr_t addr, size_t size, db_expr_t value)
   74 {
   75         char data[sizeof(db_expr_t)];
   76         int i;
   77 
   78 #ifdef DIAGNOSTIC
   79         if (size > sizeof data)
   80                 size = sizeof data;
   81 #endif
   82 
   83 #if BYTE_ORDER == LITTLE_ENDIAN
   84         for (i = 0; i < size; i++)
   85 #else /* BYTE_ORDER == BIG_ENDIAN */
   86         for (i = size - 1; i >= 0; i--)
   87 #endif /* BYTE_ORDER */
   88         {
   89                 data[i] = value & 0xff;
   90                 value >>= 8;
   91         }
   92 
   93         db_write_bytes(addr, size, data);
   94 }

Cache object: a07c7a67152bfddb3ed58f4c8acd249e

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.

FreeBSD/Linux Kernel Cross Reference sys/ddb/db_access.c

FreeBSD/Linux Kernel Cross Reference
sys/ddb/db_access.c