xref: /netbsd-src/external/gpl3/gcc.old/dist/libiberty/memcmp.c (revision 1debfc3d3fad8af6f31804271c18e67f77b4d718)
1*1debfc3dSmrg /* memcmp -- compare two memory regions.
2*1debfc3dSmrg    This function is in the public domain.  */
3*1debfc3dSmrg 
4*1debfc3dSmrg /*
5*1debfc3dSmrg 
6*1debfc3dSmrg @deftypefn Supplemental int memcmp (const void *@var{x}, const void *@var{y}, @
7*1debfc3dSmrg   size_t @var{count})
8*1debfc3dSmrg 
9*1debfc3dSmrg Compares the first @var{count} bytes of two areas of memory.  Returns
10*1debfc3dSmrg zero if they are the same, a value less than zero if @var{x} is
11*1debfc3dSmrg lexically less than @var{y}, or a value greater than zero if @var{x}
12*1debfc3dSmrg is lexically greater than @var{y}.  Note that lexical order is determined
13*1debfc3dSmrg as if comparing unsigned char arrays.
14*1debfc3dSmrg 
15*1debfc3dSmrg @end deftypefn
16*1debfc3dSmrg 
17*1debfc3dSmrg */
18*1debfc3dSmrg 
19*1debfc3dSmrg #include <ansidecl.h>
20*1debfc3dSmrg #include <stddef.h>
21*1debfc3dSmrg 
22*1debfc3dSmrg int
memcmp(const PTR str1,const PTR str2,size_t count)23*1debfc3dSmrg memcmp (const PTR str1, const PTR str2, size_t count)
24*1debfc3dSmrg {
25*1debfc3dSmrg   register const unsigned char *s1 = (const unsigned char*)str1;
26*1debfc3dSmrg   register const unsigned char *s2 = (const unsigned char*)str2;
27*1debfc3dSmrg 
28*1debfc3dSmrg   while (count-- > 0)
29*1debfc3dSmrg     {
30*1debfc3dSmrg       if (*s1++ != *s2++)
31*1debfc3dSmrg 	  return s1[-1] < s2[-1] ? -1 : 1;
32*1debfc3dSmrg     }
33*1debfc3dSmrg   return 0;
34*1debfc3dSmrg }
35*1debfc3dSmrg 
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