Merge pull request #582 from molekamp/ReopenableRotatingFileOutputStream-windows

fixed [JENKINS-15408]: Rotation of slave launch logs on Windows

changelog.html

@@ -70,6 +70,9 @@ Upcoming changes</a>
   <li class="major bug">
     Jenkins kicks off the wrong downstream builds for Maven.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-15367">issue 15367</a>)
+  <li class=bug>
+    Rotation of slave agent launch logs is broken for Windows masters.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-15408">issue 15408</a>)
 </ul>
 </div><!--=TRUNK-END=-->
 

core/src/main/java/hudson/util/io/ReopenableRotatingFileOutputStream.java

@@ -54,7 +54,9 @@ public class ReopenableRotatingFileOutputStream extends ReopenableFileOutputStre
         for (int i=size-1;i>=0;i--) {
             File fi = getNumberedFileName(i);
             if (fi.exists()) {
-                fi.renameTo(getNumberedFileName(i+1));
+                File next = getNumberedFileName(i+1);
+                next.delete();
+                fi.renameTo(next);
             }
         }
     }