osfmk/ddb/db_access.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1991,1990 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50 /*
  51  */
  52 /*
  53  *      Author: David B. Golub, Carnegie Mellon University
  54  *      Date:   7/90
  55  */
  56 #include <mach/boolean.h>
  57 #include <machine/db_machdep.h>         /* type definitions */
  58 #include <machine/setjmp.h>
  59 #include <machine/endian.h>
  60 #include <kern/task.h>
  61 #include <ddb/db_access.h>
  62
  63
  64
  65 /*
  66  * Access unaligned data items on aligned (longword)
  67  * boundaries.
  68  */
  69
  70 int db_access_level = DB_ACCESS_LEVEL;
  71
  72 db_expr_t
  73 db_get_task_value(
  74         db_addr_t       addr,
  75         register int    size,
  76         boolean_t       is_signed,
  77         task_t          task)
  78 {
  79         char            data[sizeof(db_expr_t)];
  80         register db_expr_t value;
  81         register int    i;
  82         uint64_t signx;
  83
  84         if(size == 0) return 0;
  85
  86         db_read_bytes((vm_offset_t)addr, size, data, task);
  87
  88         value = 0;
  89 #if     BYTE_MSF
  90         for (i = 0; i < size; i++)
  91 #else   /* BYTE_LSF */
  92         for (i = size - 1; i >= 0; i--)
  93 #endif
  94         {
  95             value = (value << 8) + (data[i] & 0xFF);
  96         }
  97
  98         if(!is_signed) return value;
  99
 100         signx = 0xFFFFFFFFFFFFFFFFULL << ((size << 3) - 1);
 101
 102         if(value & signx) value |= signx;       /* Add 1s to front if sign bit is on */
 103
 104         return (value);
 105 }
 106
 107 void
 108 db_put_task_value(
 109         db_addr_t       addr,
 110         register int    size,
 111         register db_expr_t value,
 112         task_t          task)
 113 {
 114         char            data[sizeof(db_expr_t)];
 115         register int    i;
 116
 117 #if     BYTE_MSF
 118         for (i = size - 1; i >= 0; i--)
 119 #else   /* BYTE_LSF */
 120         for (i = 0; i < size; i++)
 121 #endif
 122         {
 123             data[i] = value & 0xFF;
 124             value >>= 8;
 125         }
 126
 127         db_write_bytes((vm_offset_t)addr, size, data, task);
 128 }
 129
 130 db_expr_t
 131 db_get_value(
 132         db_addr_t       addr,
 133         int             size,
 134         boolean_t       is_signed)
 135 {
 136         return(db_get_task_value(addr, size, is_signed, TASK_NULL));
 137 }
 138
 139 void
 140 db_put_value(
 141         db_addr_t       addr,
 142         int             size,
 143         db_expr_t       value)
 144 {
 145         db_put_task_value(addr, size, value, TASK_NULL);
 146 }