1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
/* memcmp -- compare two memory regions.
This function is in the public domain. */
/*
@deftypefn Supplemental int memcmp (const void *@var{x}, const void *@var{y}, @
size_t @var{count})
Compares the first @var{count} bytes of two areas of memory. Returns
zero if they are the same, a value less than zero if @var{x} is
lexically less than @var{y}, or a value greater than zero if @var{x}
is lexically greater than @var{y}. Note that lexical order is determined
as if comparing unsigned char arrays.
@end deftypefn
*/
#include <ansidecl.h>
#include <stddef.h>
int
memcmp (const PTR str1, const PTR str2, size_t count)
{
register const unsigned char *s1 = (const unsigned char*)str1;
register const unsigned char *s2 = (const unsigned char*)str2;
while (count-- > 0)
{
if (*s1++ != *s2++)
return s1[-1] < s2[-1] ? -1 : 1;
}
return 0;
}
|
