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From: philip@beeblebrox.dle.dg.com (Philip Gladstone)
Newsgroups: comp.protocols.time.ntp
Subject: Bug in xntp version 1.3 in clock selection
Message-ID: <auto-repost.17945@dle.dg.com>
Date: 6 Jun 91 15:35:13 GMT
Sender: usenet@dle.dg.com (Net News)
Distribution: comp
Organization: Data General, Development Lab Europe
Lines: 87

I found a nasty bug this morning in the clock selection code in xntp
1.3. It turns out that the casting out of outlying clocks is just done
wrong. This results in incorrect clock selections. I enclose the
(trivial) patch.

Apply in the xntpd directory with 'patch < filename'

Good luck.

        Philip

---cut here
*** orig_ntp_proto.c	Thu Jun  6 12:14:15 1991
--- ntp_proto.c	Thu Jun  6 12:49:06 1991
***************
*** 1561,1566 ****
--- 1561,1568 ----
  					 */
  					for (i = 0; i < j; i++)
  					    d = (d>>1) + (d>>2);
+                                         
+                                         peer_badness[n] += d;
  				    }
  				    break;
  
***************
*** 1600,1605 ****
--- 1602,1609 ----
  					    else
  						d = (d>>1) + (d>>2);
  					}
+ 				
+                                         peer_badness[n] += d;
  				    }
  				    break;
  
***************
*** 1638,1643 ****
--- 1642,1649 ----
  					    else
  						d = (d>>1) + (d>>2);
  					}
+ 				
+                                         peer_badness[n] += d;
  				    }
  				    break;
  
***************
*** 1659,1664 ****
--- 1665,1672 ----
  					 */
  					for (i = 0; i < j; i++)
  					    d = (d>>1) + (d>>3) + (d>>4);
+ 				
+                                         peer_badness[n] += d;
  				    }
  				    break;
  
***************
*** 1680,1685 ****
--- 1688,1695 ----
  					 */
  					for (i = 0; i < j; i++)
  					    d = (d>>1) + (d>>3);
+ 				
+                                         peer_badness[n] += d;
  				    }
  				    break;
  
***************
*** 1692,1698 ****
  					sys_select_algorithm);
  				    exit(1);
  				}
- 				peer_badness[n] += d;
  			}
  
  			/*
--- 1702,1707 ----

--- end of patch
--
Philip Gladstone         Dev Lab Europe, Data General, Cambridge, UK

    I seem to be having this tremendous difficulty with my lifestyle.
 
***WARNING: This article may be a duplicate....