osfmk/i386/loose_ends.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) 1991,1990,1989 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 #include <mach_assert.h>
  53
  54 #include <string.h>
  55 #include <mach/boolean.h>
  56 #include <mach/i386/vm_types.h>
  57 #include <kern/kern_types.h>
  58 #include <kern/misc_protos.h>
  59 #include <i386/misc_protos.h>
  60
  61         /*
  62          * Should be rewritten in asm anyway.
  63          */
  64 /*
  65  * ovbcopy - like bcopy, but recognizes overlapping ranges and handles
  66  *           them correctly.
  67  */
  68
  69 void
  70 ovbcopy(
  71         const char      *from,
  72         char            *to,
  73         vm_size_t       bytes)          /* num bytes to copy */
  74 {
  75         /* Assume that bcopy copies left-to-right (low addr first). */
  76         if (from + bytes <= to || to + bytes <= from || to == from)
  77                 bcopy_no_overwrite(from, to, bytes);    /* non-overlapping or no-op*/
  78         else if (from > to)
  79                 bcopy_no_overwrite(from, to, bytes);    /* overlapping but OK */
  80         else {
  81                 /* to > from: overlapping, and must copy right-to-left. */
  82                 from += bytes - 1;
  83                 to += bytes - 1;
  84                 while (bytes-- > 0)
  85                         *to-- = *from--;
  86         }
  87 }
  88
  89 void
  90 bcopy(
  91         const char      *from,
  92         char            *to,
  93         vm_size_t       bytes)          /* num bytes to copy */
  94 {
  95         ovbcopy(from, to, bytes);
  96 }
  97
  98 int bcmp(
  99         const char      *a,
 100         const char      *b,
 101         vm_size_t       len)
 102 {
 103         if (len == 0)
 104                 return 0;
 105
 106         do
 107                 if (*a++ != *b++)
 108                         break;
 109         while (--len);
 110
 111         return len;
 112 }
 113
 114 #if     MACH_ASSERT
 115
 116 /*
 117  * Machine-dependent routine to fill in an array with up to callstack_max
 118  * levels of return pc information.
 119  */
 120 void machine_callstack(
 121         natural_t       *buf,
 122         vm_size_t       callstack_max)
 123 {
 124 }
 125
 126 #endif  /* MACH_ASSERT */