metal-cos/sys/kern/libc.c
2014-07-06 00:07:32 -07:00

67 lines
959 B
C

/*
* Copyright (c) 2013-2014 Stanford University
* Copyright (c) 2006-2008 Ali Mashtizadeh
* All rights reserved.
*/
#include <string.h>
char *
strcpy(char *to, const char *from)
{
char *save = to;
for (; (*to = *from); ++from, ++to);
return save;
}
int
strcmp(const char *s1, const char *s2)
{
while (*s1 == *s2++)
if (*s1++ == 0)
return 0;
return (*(const uint8_t *)s1 - *(const uint8_t *)(s2 - 1));
}
size_t
strlen(const char *str)
{
const char *s;
for (s = str; *s; ++s);
return (s - str);
}
void *
memset(void *dst, int c, size_t length)
{
uint8_t *p = (uint8_t *)dst;
do {
*p = c;
p += 1;
} while (--length != 0);
return dst;
}
void *
memcpy(void *dst, const void *src, size_t length)
{
uint8_t *d = (uint8_t *)dst;
const uint8_t *s = (const uint8_t *)src;
do {
*d = *s;
d += 1;
s += 1;
} while (--length != 0);
return dst;
}