osfmk/ddb/db_access.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58 /*
  59  *      Author: David B. Golub, Carnegie Mellon University
  60  *      Date:   7/90
  61  */
  62 #include <mach/boolean.h>
  63 #include <machine/db_machdep.h>         /* type definitions */
  64 #include <machine/setjmp.h>
  65 #include <machine/endian.h>
  66 #include <kern/task.h>
  67 #include <ddb/db_access.h>
  68
  69
  70
  71 /*
  72  * Access unaligned data items on aligned (longword)
  73  * boundaries.
  74  */
  75
  76 int db_access_level = DB_ACCESS_LEVEL;
  77
  78 db_expr_t
  79 db_get_task_value(
  80         db_addr_t       addr,
  81         register int    size,
  82         boolean_t       is_signed,
  83         task_t          task)
  84 {
  85         char            data[sizeof(db_expr_t)];
  86         register db_expr_t value;
  87         register int    i;
  88         uint64_t signx;
  89
  90         if(size == 0) return 0;
  91
  92         db_read_bytes((vm_offset_t)addr, size, data, task);
  93
  94         value = 0;
  95 #if     BYTE_MSF
  96         for (i = 0; i < size; i++)
  97 #else   /* BYTE_LSF */
  98         for (i = size - 1; i >= 0; i--)
  99 #endif
 100         {
 101             value = (value << 8) + (data[i] & 0xFF);
 102         }
 103
 104         if(!is_signed) return value;
 105
 106         signx = 0xFFFFFFFFFFFFFFFFULL << ((size << 3) - 1);
 107
 108         if(value & signx) value |= signx;       /* Add 1s to front if sign bit is on */
 109
 110         return (value);
 111 }
 112
 113 void
 114 db_put_task_value(
 115         db_addr_t       addr,
 116         register int    size,
 117         register db_expr_t value,
 118         task_t          task)
 119 {
 120         char            data[sizeof(db_expr_t)];
 121         register int    i;
 122
 123 #if     BYTE_MSF
 124         for (i = size - 1; i >= 0; i--)
 125 #else   /* BYTE_LSF */
 126         for (i = 0; i < size; i++)
 127 #endif
 128         {
 129             data[i] = value & 0xFF;
 130             value >>= 8;
 131         }
 132
 133         db_write_bytes((vm_offset_t)addr, size, data, task);
 134 }
 135
 136 db_expr_t
 137 db_get_value(
 138         db_addr_t       addr,
 139         int             size,
 140         boolean_t       is_signed)
 141 {
 142         return(db_get_task_value(addr, size, is_signed, TASK_NULL));
 143 }
 144
 145 void
 146 db_put_value(
 147         db_addr_t       addr,
 148         int             size,
 149         db_expr_t       value)
 150 {
 151         db_put_task_value(addr, size, value, TASK_NULL);
 152 }