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/*
*
* It has originally been taken from the HelenOS project
* (http://www.helenos.eu), and slightly modified for our purposes.
*
* Copyright (c) 2005 Martin Decky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <libpayload.h>
static void *default_memset(void *const s, const int c, size_t n)
{
size_t i;
u8 *dst = s;
unsigned long w = c & 0xff;
const u8 *const aligned_start =
(const u8 *)ALIGN_UP((uintptr_t)dst, sizeof(unsigned long));
for (; n > 0 && dst != aligned_start; --n, ++dst)
*dst = (u8)c;
for (i = 1; i < sizeof(unsigned long); i <<= 1)
w = (w << (i * 8)) | w;
for (i = 0; i < n / sizeof(unsigned long); i++)
((unsigned long *)dst)[i] = w;
dst += i * sizeof(unsigned long);
for (i = 0; i < n % sizeof(unsigned long); i++)
dst[i] = (u8)c;
return s;
}
void *memset(void *s, int c, size_t n)
__attribute__((weak, alias("default_memset")));
static void *default_memcpy(void *dst, const void *src, size_t n)
{
size_t i;
void *ret = dst;
if (IS_ALIGNED((uintptr_t)dst, sizeof(unsigned long)) &&
IS_ALIGNED((uintptr_t)src, sizeof(unsigned long))) {
for (i = 0; i < n / sizeof(unsigned long); i++)
((unsigned long *)dst)[i] = ((unsigned long *)src)[i];
src += i * sizeof(unsigned long);
dst += i * sizeof(unsigned long);
n -= i * sizeof(unsigned long);
}
for (i = 0; i < n; i++)
((u8 *)dst)[i] = ((u8 *)src)[i];
return ret;
}
void *memcpy(void *dst, const void *src, size_t n)
__attribute__((weak, alias("default_memcpy")));
static void *default_memmove(void *dst, const void *src, size_t n)
{
size_t offs;
ssize_t i;
if (src > dst)
return memcpy(dst, src, n);
if (!IS_ALIGNED((uintptr_t)dst, sizeof(unsigned long)) ||
!IS_ALIGNED((uintptr_t)src, sizeof(unsigned long))) {
for (i = n - 1; i >= 0; i--)
((u8 *)dst)[i] = ((u8 *)src)[i];
return dst;
}
offs = n - (n % sizeof(unsigned long));
for (i = (n % sizeof(unsigned long)) - 1; i >= 0; i--)
((u8 *)dst)[i + offs] = ((u8 *)src)[i + offs];
for (i = n / sizeof(unsigned long) - 1; i >= 0; i--)
((unsigned long *)dst)[i] = ((unsigned long *)src)[i];
return dst;
}
void *memmove(void *dst, const void *src, size_t n)
__attribute__((weak, alias("default_memmove")));
/**
* Compare two memory areas.
*
* @param s1 Pointer to the first area to compare.
* @param s2 Pointer to the second area to compare.
* @param n Size of the first area in bytes (both must have the same length).
* @return If n is 0, return zero. Otherwise, return a value less than, equal
* to, or greater than zero if s1 is found less than, equal to, or
* greater than s2 respectively.
*/
static int default_memcmp(const void *s1, const void *s2, size_t n)
{
size_t i = 0;
const unsigned long *w1 = s1, *w2 = s2;
if (IS_ALIGNED((uintptr_t)s1, sizeof(unsigned long)) &&
IS_ALIGNED((uintptr_t)s2, sizeof(unsigned long)))
for (; i < n / sizeof(unsigned long); i++)
if (w1[i] != w2[i])
break; /* fall through to find differing byte */
for (i *= sizeof(unsigned long); i < n; i++)
if (((u8 *)s1)[i] != ((u8 *)s2)[i])
return ((u8 *)s1)[i] - ((u8 *)s2)[i];
return 0;
}
int memcmp(const void *s1, const void *s2, size_t n)
__attribute__((weak, alias("default_memcmp")));
void *memchr(const void *s, int c, size_t n)
{
unsigned char *p = (unsigned char *)s;
while (n--)
if (*p != (unsigned char)c)
p++;
else
return p;
return 0;
}
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