1extern void abort (void);
2extern int inside_main;
3
4typedef __SIZE_TYPE__ size_t;
5
6int
7strncmp(const char *s1, const char *s2, size_t n)
8{
9  const unsigned char *u1 = (const unsigned char *)s1;
10  const unsigned char *u2 = (const unsigned char *)s2;
11  unsigned char c1, c2;
12
13#ifdef __OPTIMIZE__
14  if (inside_main)
15    abort();
16#endif
17
18  while (n > 0)
19    {
20      c1 = *u1++, c2 = *u2++;
21      if (c1 == '\0' || c1 != c2)
22	return c1 - c2;
23      n--;
24    }
25  return c1 - c2;
26}
27