// TODO: CHECK/REPLACE/UPDATE OLD CODE (this file is based on xv6)
#include "types.h"

#define KERNEL_MODE
#include <libc/string.c>

int
memcmp(const void *v1, const void *v2, uint n)
{
  const uchar *s1, *s2;

  s1 = v1;
  s2 = v2;
  while(n-- > 0){
    if(*s1 != *s2)
      return *s1 - *s2;
    s1++, s2++;
  }

  return 0;
}

void*
memmove(void *dst, const void *src, uint n)
{
  const char *s;
  char *d;

  if(n == 0)
    return dst;
  
  s = src;
  d = dst;
  if(s < d && s + n > d){
    s += n;
    d += n;
    while(n-- > 0)
      *--d = *--s;
  } else {
	#ifdef _ZCC
	//if (n >= 8 && (d + n < s || s + n < d)) {
  //    return memcpy_opt(dst, src, n);
		/*uint smalln = n %8;
		uint bign = n - smalln;
		memcpy_quick64(dst, src, bign);
		d += bign;
		s += bign;
		n = smalln;*/
	//}
	#endif
    while(n-- > 0)
      *d++ = *s++;
  }

  return dst;
}

int
strncmp(const char *p, const char *q, uint n)
{
  while(n > 0 && *p && *p == *q)
    n--, p++, q++;
  if(n == 0)
    return 0;
  return (uchar)*p - (uchar)*q;
}

// Like strncpy but guaranteed to NUL-terminate.
char*
safestrcpy(char *s, const char *t, int n)
{
  char *os;

  os = s;
  if(n <= 0)
    return os;
  while(--n > 0 && (*s++ = *t++) != 0)
    ;
  *s = 0;
  return os;
}