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#include <string.h>
static void *__memmove_down(void *__dest, __const void *__src, size_t __n)
{
unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
while (__n--)
*d++ = *s++;
return __dest;
}
static void *__memmove_up(void *__dest, __const void *__src, size_t __n)
{
unsigned char *d = (unsigned char *)__dest + __n - 1, *s = (unsigned char *)__src + __n - 1;
while (__n--)
*d-- = *s--;
return __dest;
}
void *(memcpy)(void *__dest, __const void *__src, size_t __n)
{
return __memmove_down(__dest, __src, __n);
}
void *(memmove)(void *__dest, __const void *__src, size_t __n)
{
if(__dest > __src)
return __memmove_up(__dest, __src, __n);
else
return __memmove_down(__dest, __src, __n);
}
void *(memchr)(void const *s, int c, size_t n)
{
unsigned char const *_s = (unsigned char const *)s;
while(n && *_s != c) {
++_s;
--n;
}
if(n)
return (void *)_s; /* the C library casts const away */
else
return (void *)0;
}
size_t (strlen)(const char *s)
{
const char *sc = s;
while (*sc != '\0')
sc++;
return sc - s;
}
void *(memset)(void *s, int c, size_t count)
{
char *xs = s;
while (count--)
*xs++ = c;
return s;
}
int (memcmp)(void const *p1, void const *p2, size_t n)
{
unsigned char const *_p1 = p1;
unsigned char const *_p2 = p2;
while(n--) {
if(*_p1 < *_p2)
return -1;
else if(*_p1 > *_p2)
return 1;
++_p1;
++_p2;
}
return 0;
}
int (strcmp)(char const *s1, char const *s2)
{
while(*s1 && *s2) {
if(*s1 < *s2)
return -1;
else if(*s1 > *s2)
return 1;
++s1;
++s2;
}
if(!*s1 && !*s2)
return 0;
else if(!*s1)
return -1;
else
return 1;
}
int (strncmp)(char const *s1, char const *s2, size_t n)
{
while(*s1 && *s2 && n--) {
if(*s1 < *s2)
return -1;
else if(*s1 > *s2)
return 1;
++s1;
++s2;
}
if(n == 0 || (!*s1 && !*s2))
return 0;
else if(!*s1)
return -1;
else
return 1;
}
char *(strchr)(char const *s, int c)
{
unsigned char const *_s = (unsigned char const *)s;
while(*_s && *_s != c)
++_s;
if(*_s)
return (char *)_s; /* the C library casts const away */
else
return (char *)0;
}
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