IABSD.fr/src/sys/ddb/db_access.c

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• Author : mpi
  Date : 2019-11-07 13:16:25
  Hash : 08f058f8
  Message : db_addr_t -> vaddr_t ok deraadt@

• sys/ddb/db_access.c

• /*	$OpenBSD: db_access.c,v 1.16 2019/11/07 13:16:25 mpi Exp $	*/
  /*	$NetBSD: db_access.c,v 1.8 1994/10/09 08:37:35 mycroft Exp $	*/
  
  /*
   * Mach Operating System
   * Copyright (c) 1991,1990 Carnegie Mellon University
   * All Rights Reserved.
   *
   * Permission to use, copy, modify and distribute this software and its
   * documentation is hereby granted, provided that both the copyright
   * notice and this permission notice appear in all copies of the
   * software, derivative works or modified versions, and any portions
   * thereof, and that both notices appear in supporting documentation.
   *
   * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
   * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
   * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   *
   * Carnegie Mellon requests users of this software to return to
   *
   *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   *  School of Computer Science
   *  Carnegie Mellon University
   *  Pittsburgh PA 15213-3890
   *
   * any improvements or extensions that they make and grant Carnegie the
   * the rights to redistribute these changes.
   *
   *	Author: David B. Golub, Carnegie Mellon University
   *	Date:	7/90
   */
  
  #include <sys/param.h>
  #include <sys/endian.h>
  
  #include <machine/db_machdep.h>		/* type definitions */
  
  #include <ddb/db_access.h>
  
  /*
   * Access unaligned data items on aligned (longword)
   * boundaries.
   */
  db_expr_t
  db_get_value(vaddr_t addr, size_t size, int is_signed)
  {
  	char data[sizeof(db_expr_t)];
  	db_expr_t value, extend;
  	int i;
  
  #ifdef DIAGNOSTIC
  	if (size > sizeof data)
  		size = sizeof data;
  #endif
  
  	db_read_bytes(addr, size, data);
  
  	value = 0;
  	extend = (~(db_expr_t)0) << (size * 8 - 1);
  #if BYTE_ORDER == LITTLE_ENDIAN
  	for (i = size - 1; i >= 0; i--)
  #else /* BYTE_ORDER == BIG_ENDIAN */
  	for (i = 0; i < size; i++)
  #endif /* BYTE_ORDER */
  		value = (value << 8) + (data[i] & 0xFF);
  
  	if (size < sizeof(db_expr_t) && is_signed && (value & extend))
  		value |= extend;
  	return (value);
  }
  
  void
  db_put_value(vaddr_t addr, size_t size, db_expr_t value)
  {
  	char data[sizeof(db_expr_t)];
  	int i;
  
  #ifdef DIAGNOSTIC
  	if (size > sizeof data)
  		size = sizeof data;
  #endif
  
  #if BYTE_ORDER == LITTLE_ENDIAN
  	for (i = 0; i < size; i++)
  #else /* BYTE_ORDER == BIG_ENDIAN */
  	for (i = size - 1; i >= 0; i--)
  #endif /* BYTE_ORDER */
  	{
  		data[i] = value & 0xff;
  		value >>= 8;
  	}
  
  	db_write_bytes(addr, size, data);
  }