osfmk/ddb/db_access.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30 /*
  31  * @OSF_COPYRIGHT@
  32  */
  33 /*
  34  * Mach Operating System
  35  * Copyright (c) 1991,1990 Carnegie Mellon University
  36  * All Rights Reserved.
  37  *
  38  * Permission to use, copy, modify and distribute this software and its
  39  * documentation is hereby granted, provided that both the copyright
  40  * notice and this permission notice appear in all copies of the
  41  * software, derivative works or modified versions, and any portions
  42  * thereof, and that both notices appear in supporting documentation.
  43  *
  44  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  45  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  46  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  47  *
  48  * Carnegie Mellon requests users of this software to return to
  49  *
  50  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  51  *  School of Computer Science
  52  *  Carnegie Mellon University
  53  *  Pittsburgh PA 15213-3890
  54  *
  55  * any improvements or extensions that they make and grant Carnegie Mellon
  56  * the rights to redistribute these changes.
  57  */
  58 /*
  59  */
  60 /*
  61  *      Author: David B. Golub, Carnegie Mellon University
  62  *      Date:   7/90
  63  */
  64 #include <mach/boolean.h>
  65 #include <machine/db_machdep.h>         /* type definitions */
  66 #include <machine/setjmp.h>
  67 #include <machine/endian.h>
  68 #include <kern/task.h>
  69 #include <ddb/db_access.h>
  70
  71
  72
  73 /*
  74  * Access unaligned data items on aligned (longword)
  75  * boundaries.
  76  */
  77
  78 int db_access_level = DB_ACCESS_LEVEL;
  79
  80 db_expr_t
  81 db_get_task_value(
  82         db_addr_t       addr,
  83         register int    size,
  84         boolean_t       is_signed,
  85         task_t          task)
  86 {
  87         char            data[sizeof(db_expr_t)];
  88         register db_expr_t value;
  89         register int    i;
  90         uint64_t signx;
  91
  92         if(size == 0) return 0;
  93
  94         db_read_bytes((vm_offset_t)addr, size, data, task);
  95
  96         value = 0;
  97 #if     BYTE_MSF
  98         for (i = 0; i < size; i++)
  99 #else   /* BYTE_LSF */
 100         for (i = size - 1; i >= 0; i--)
 101 #endif
 102         {
 103             value = (value << 8) + (data[i] & 0xFF);
 104         }
 105
 106         if(!is_signed) return value;
 107
 108         signx = 0xFFFFFFFFFFFFFFFFULL << ((size << 3) - 1);
 109
 110         if(value & signx) value |= signx;       /* Add 1s to front if sign bit is on */
 111
 112         return (value);
 113 }
 114
 115 void
 116 db_put_task_value(
 117         db_addr_t       addr,
 118         register int    size,
 119         register db_expr_t value,
 120         task_t          task)
 121 {
 122         char            data[sizeof(db_expr_t)];
 123         register int    i;
 124
 125 #if     BYTE_MSF
 126         for (i = size - 1; i >= 0; i--)
 127 #else   /* BYTE_LSF */
 128         for (i = 0; i < size; i++)
 129 #endif
 130         {
 131             data[i] = value & 0xFF;
 132             value >>= 8;
 133         }
 134
 135         db_write_bytes((vm_offset_t)addr, size, data, task);
 136 }
 137
 138 db_expr_t
 139 db_get_value(
 140         db_addr_t       addr,
 141         int             size,
 142         boolean_t       is_signed)
 143 {
 144         return(db_get_task_value(addr, size, is_signed, TASK_NULL));
 145 }
 146
 147 void
 148 db_put_value(
 149         db_addr_t       addr,
 150         int             size,
 151         db_expr_t       value)
 152 {
 153         db_put_task_value(addr, size, value, TASK_NULL);
 154 }