foboot/sw/third_party/libbase/libc.c

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/* $OpenBSD: strlen.c,v 1.8 2014/06/10 04:17:37 deraadt Exp $ */
/*-
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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 <string.h>
size_t
strlen(const char *str)
{
const char *s;
for (s = str; *s; ++s)
;
return (s - str);
}
/**
* memcpy - Copies one area of memory to another
* @dest: Destination
* @src: Source
* @n: The size to copy.
*/
void *memcpy(void *to, const void *from, size_t n)
{
void *xto = to;
size_t temp;
if(!n)
return xto;
if((long)to & 1) {
char *cto = to;
const char *cfrom = from;
*cto++ = *cfrom++;
to = cto;
from = cfrom;
n--;
}
if((long)from & 1) {
char *cto = to;
const char *cfrom = from;
for (; n; n--)
*cto++ = *cfrom++;
return xto;
}
if(n > 2 && (long)to & 2) {
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
n -= 2;
}
if((long)from & 2) {
short *sto = to;
const short *sfrom = from;
temp = n >> 1;
for (; temp; temp--)
*sto++ = *sfrom++;
to = sto;
from = sfrom;
if(n & 1) {
char *cto = to;
const char *cfrom = from;
*cto = *cfrom;
}
return xto;
}
temp = n >> 2;
if(temp) {
long *lto = to;
const long *lfrom = from;
for(; temp; temp--)
*lto++ = *lfrom++;
to = lto;
from = lfrom;
}
if(n & 2) {
short *sto = to;
const short *sfrom = from;
*sto++ = *sfrom++;
to = sto;
from = sfrom;
}
if(n & 1) {
char *cto = to;
const char *cfrom = from;
*cto = *cfrom;
}
return xto;
}