WSJT-X/libm65/igray.c
Joe Taylor 04dcf0a528 Major changes to the MAP65 branch. This branch is now a copy of
MAP65 v2.3.0, r631, as checked out from the SVN repository on
pulsar.princeton.edu.  If all goes well with this commit, subsequent
MAP65 development will use the Berlios repository.


git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/map65@2461 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2012-05-22 14:28:39 +00:00

23 lines
337 B
C

#ifdef CVF
extern int __stdcall IGRAY(int *n0, int *idir)
#else
int igray_(int *n0, int *idir)
#endif
{
int n;
unsigned long sh;
unsigned long nn;
n=*n0;
if(*idir>0) return (n ^ (n >> 1));
sh = 1;
nn = (n >> sh);
while (nn > 0) {
n ^= nn;
sh <<= 1;
nn = (n >> sh);
}
return (n);
}