source: mainline/generic/src/lib/memstr.c@ 88169d9

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 88169d9 was 2d7a5fe, checked in by Jakub Jermar <jakub@…>, 19 years ago

Generic version of memcpy that is resistent towards unaligned memory accesses.

  • Property mode set to 100644
File size: 3.4 KB
Line 
1/*
2 * Copyright (C) 2001-2004 Jakub Jermar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/**
30 * @file memstr.c
31 * @brief Memory string operations.
32 *
33 * This file provides architecture independent functions
34 * to manipulate blocks of memory. These functions
35 * are optimized as much as generic functions of
36 * this type can be. However, architectures are
37 * free to provide even more optimized versions of these
38 * functions.
39 */
40
41#include <memstr.h>
42#include <arch/types.h>
43#include <align.h>
44
45/** Copy block of memory
46 *
47 * Copy cnt bytes from src address to dst address.
48 * The copying is done word-by-word and then byte-by-byte.
49 * The source and destination memory areas cannot overlap.
50 *
51 * @param src Origin address to copy from.
52 * @param dst Origin address to copy to.
53 * @param cnt Number of bytes to copy.
54 *
55 */
56void *_memcpy(void * dst, const void *src, size_t cnt)
57{
58 int i, j;
59
60 if (ALIGN_UP((__address) src, sizeof(__native)) != (__address) src ||
61 ALIGN_UP((__address) dst, sizeof(__native)) != (__address) dst) {
62 for (i = 0; i < cnt; i++)
63 ((__u8 *) dst)[i] = ((__u8 *) src)[i];
64 } else {
65
66 for (i = 0; i < cnt/sizeof(__native); i++)
67 ((__native *) dst)[i] = ((__native *) src)[i];
68
69 for (j = 0; j < cnt%sizeof(__native); j++)
70 ((__u8 *)(((__native *) dst) + i))[j] = ((__u8 *)(((__native *) src) + i))[j];
71 }
72
73 return (char *)src;
74}
75
76/** Fill block of memory
77 *
78 * Fill cnt bytes at dst address with the value x.
79 * The filling is done byte-by-byte.
80 *
81 * @param dst Origin address to fill.
82 * @param cnt Number of bytes to fill.
83 * @param x Value to fill.
84 *
85 */
86void _memsetb(__address dst, size_t cnt, __u8 x)
87{
88 int i;
89 __u8 *p = (__u8 *) dst;
90
91 for(i=0; i<cnt; i++)
92 p[i] = x;
93}
94
95/** Fill block of memory
96 *
97 * Fill cnt words at dst address with the value x.
98 * The filling is done word-by-word.
99 *
100 * @param dst Origin address to fill.
101 * @param cnt Number of words to fill.
102 * @param x Value to fill.
103 *
104 */
105void _memsetw(__address dst, size_t cnt, __u16 x)
106{
107 int i;
108 __u16 *p = (__u16 *) dst;
109
110 for(i=0; i<cnt; i++)
111 p[i] = x;
112}
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