[FIXED JENKINS-9118]

WorkspaceSnapshot now uses the tar.gz format to handle symlinks
correctly.

changelog.html

@@ -56,7 +56,8 @@ Upcoming changes</a>
 <div id="trunk" style="display:none"><!--=TRUNK-BEGIN=-->
 <ul class=image>
   <li class=bug>
-    tar/untar now correctly handles symlinks.
+    Workspace archiving wasn't handling symlinks correctly.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-9118">issue 9118</a>)
   <li class=bug>
     Fixed a bug in the auto-overwrite of bundled plugins on Windows.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-12514">issue 12514</a>)

core/src/main/java/hudson/FilePath.java

@@ -415,11 +415,11 @@ public final class FilePath implements Serializable {
         });
     }
 
-    private int archive(final ArchiverFactory factory, OutputStream os, final FileFilter filter) throws IOException, InterruptedException {
+    public int archive(final ArchiverFactory factory, OutputStream os, final FileFilter filter) throws IOException, InterruptedException {
         return archive(factory,os,new DirScanner.Filter(filter));
     }
 
-    private int archive(final ArchiverFactory factory, OutputStream os, final String glob) throws IOException, InterruptedException {
+    public int archive(final ArchiverFactory factory, OutputStream os, final String glob) throws IOException, InterruptedException {
         return archive(factory,os,new DirScanner.Glob(glob,null));
     }
 

core/src/main/java/hudson/FileSystemProvisioner.java

@@ -23,6 +23,7 @@
  */
 package hudson;
 
+import hudson.FilePath.TarCompression;
 import hudson.matrix.MatrixBuild;
 import hudson.model.AbstractBuild;
 import hudson.model.AbstractProject;
@@ -30,6 +31,8 @@ import hudson.model.Computer;
 import hudson.model.Describable;
 import hudson.model.Job;
 import hudson.model.TaskListener;
+import hudson.util.DirScanner.Glob;
+import hudson.util.io.ArchiverFactory;
 import jenkins.model.Jenkins;
 import hudson.model.listeners.RunListener;
 import hudson.scm.SCM;
@@ -211,10 +214,10 @@ public abstract class FileSystemProvisioner implements ExtensionPoint, Describab
          * Creates a tar ball.
          */
         public WorkspaceSnapshot snapshot(AbstractBuild<?, ?> build, FilePath ws, String glob, TaskListener listener) throws IOException, InterruptedException {
-            File wss = new File(build.getRootDir(),"workspace.zip");
+            File wss = new File(build.getRootDir(),"workspace.tgz");
             OutputStream os = new BufferedOutputStream(new FileOutputStream(wss));
             try {
-                ws.zip(os,glob);
+                ws.archive(ArchiverFactory.TARGZ,os,glob);
             } finally {
                 os.close();
             }
@@ -223,8 +226,13 @@ public abstract class FileSystemProvisioner implements ExtensionPoint, Describab
 
         public static final class WorkspaceSnapshotImpl extends WorkspaceSnapshot {
             public void restoreTo(AbstractBuild<?,?> owner, FilePath dst, TaskListener listener) throws IOException, InterruptedException {
-                File wss = new File(owner.getRootDir(),"workspace.zip");
-                new FilePath(wss).unzip(dst);
+                File zip = new File(owner.getRootDir(),"workspace.zip");
+                if (zip.exists()) {// we used to keep it in zip
+                    new FilePath(zip).unzip(dst);
+                } else {// but since 1.456 we do tgz
+                    File tgz = new File(owner.getRootDir(),"workspace.tgz");
+                    new FilePath(tgz).untar(dst, TarCompression.GZIP);
+                }
             }
         }