adding a switch for using shorter path names.

git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@5754 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/matrix/Combination.java

 package hudson.matrix;
 
+import hudson.Util;
+
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.StringTokenizer;
 import java.util.TreeMap;
-import java.util.Collection;
-import java.util.Set;
-import java.util.HashSet;
 
 /**
  * A particular combination of {@link Axis} values.
@@ -90,6 +92,13 @@ public final class Combination extends TreeMap<String,String> implements Compara
         return toString(',','=');
     }
 
+    /**
+     * Gets the 8 character-wide hash code for this combination
+     */
+    public String digest() {
+        return Util.getDigestOf(toString());
+    }
+
     /**
      * Reverse operation of {@link #toString()}.
      */

core/src/main/java/hudson/matrix/MatrixConfiguration.java

@@ -112,7 +112,10 @@ public class MatrixConfiguration extends Project<MatrixConfiguration,MatrixRun>
         if(node==null)  node = Hudson.getInstance();
         FilePath ws = node.getWorkspaceFor(getParent());
         if(ws==null)    return null;
-        return ws.child(getCombination().toString('/','/'));
+        if(useShortWorkspaceName)
+            return ws.child(getCombination().digest());
+        else
+            return ws.child(getCombination().toString('/','/'));
     }
 
     @Override
@@ -226,4 +229,14 @@ public class MatrixConfiguration extends Project<MatrixConfiguration,MatrixRun>
     public boolean isActiveConfiguration() {
         return getParent().getActiveConfigurations().contains(this);
     }
+
+    /**
+     * On Cygwin, path names cannot be longer than 256 chars.
+     * See http://cygwin.com/ml/cygwin/2005-04/msg00395.html and
+     * http://www.nabble.com/Windows-Filename-too-long-errors-t3161089.html for
+     * the background of this issue. Setting this flag to true would
+     * cause Hudson to use cryptic but short path name, giving more room for
+     * jobs to use longer path names.
+     */
+    public static boolean useShortWorkspaceName = Boolean.getBoolean(MatrixConfiguration.class.getName()+".useShortWorkspaceName");
 }