xref: /netbsd-src/external/gpl3/gcc/dist/libiberty/memcmp.c (revision 48fb7bfab72acd4281a53bbee5ccf3f809019e75)
14fee23f9Smrg /* memcmp -- compare two memory regions.
24fee23f9Smrg    This function is in the public domain.  */
34fee23f9Smrg 
44fee23f9Smrg /*
54fee23f9Smrg 
6*48fb7bfaSmrg @deftypefn Supplemental int memcmp (const void *@var{x}, const void *@var{y}, @
7*48fb7bfaSmrg   size_t @var{count})
84fee23f9Smrg 
94fee23f9Smrg Compares the first @var{count} bytes of two areas of memory.  Returns
104fee23f9Smrg zero if they are the same, a value less than zero if @var{x} is
114fee23f9Smrg lexically less than @var{y}, or a value greater than zero if @var{x}
124fee23f9Smrg is lexically greater than @var{y}.  Note that lexical order is determined
134fee23f9Smrg as if comparing unsigned char arrays.
144fee23f9Smrg 
154fee23f9Smrg @end deftypefn
164fee23f9Smrg 
174fee23f9Smrg */
184fee23f9Smrg 
194fee23f9Smrg #include <ansidecl.h>
204fee23f9Smrg #include <stddef.h>
214fee23f9Smrg 
224fee23f9Smrg int
memcmp(const PTR str1,const PTR str2,size_t count)234fee23f9Smrg memcmp (const PTR str1, const PTR str2, size_t count)
244fee23f9Smrg {
254fee23f9Smrg   register const unsigned char *s1 = (const unsigned char*)str1;
264fee23f9Smrg   register const unsigned char *s2 = (const unsigned char*)str2;
274fee23f9Smrg 
284fee23f9Smrg   while (count-- > 0)
294fee23f9Smrg     {
304fee23f9Smrg       if (*s1++ != *s2++)
314fee23f9Smrg 	  return s1[-1] < s2[-1] ? -1 : 1;
324fee23f9Smrg     }
334fee23f9Smrg   return 0;
344fee23f9Smrg }
354fee23f9Smrg 
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