1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
|
/* Copyright (C) 1998 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
USA. */
/* Last ditch effort to support memmove: if user doesn't have
memmove or bcopy, we offer this sluggish implementation. */
#include "config.h"
#ifndef HAVE_MEMMOVE
#include <sys/types.h>
#ifdef HAVE_MEMORY_H
# include <memory.h>
#endif
#ifndef VOID
# define VOID void
#endif
VOID *
memmove(dest, src, len)
VOID *dest;
const VOID *src;
size_t len;
{
#ifdef HAVE_BCOPY
bcopy(src, dest, len);
#else /*!HAVE_BCOPY*/
char *dp = dest;
const char *sp = src;
# ifdef HAVE_MEMCPY
/* A special-case for non-overlapping regions, on the assumption
that there is some hope that the sytem's memcpy() implementaion
is better than our dumb fall-back one. */
if ((dp < sp && dp+len < sp) || (sp < dp && sp+len < dp))
return memcpy(dest, src, len);
# endif
/* I tried real hard to avoid getting to this point.
You *really* ought to upgrade your system's libraries;
the performance of this implementation sucks. */
if (dp < sp)
{
while (len-- > 0)
*dp++ = *sp++;
}
else
{
if (dp == sp)
return dest;
dp += len;
sp += len;
while (len-- > 0)
*--dp = *--sp;
}
#endif /*!HAVE_BCOPY*/
return dest;
}
#endif /*!HAVE_MEMMOVE*/
|
