added isabelle remote_dmg tool;

--- a/src/Pure/System/isabelle_tool.scala	Tue Oct 11 10:43:27 2016 +0200
+++ b/src/Pure/System/isabelle_tool.scala	Tue Oct 11 11:30:02 2016 +0200
@@ -106,6 +106,7 @@
       Doc.isabelle_tool,
       ML_Process.isabelle_tool,
       Options.isabelle_tool,
+      Remote_DMG.isabelle_tool,
       Update_Cartouches.isabelle_tool,
       Update_Header.isabelle_tool,
       Update_Then.isabelle_tool,

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/Tools/remote_dmg.scala	Tue Oct 11 11:30:02 2016 +0200
@@ -0,0 +1,64 @@
+/*  Title:      Pure/Tools/remote_dmg.scala
+    Author:     Makarius
+
+Build dmg on remote Mac OS X system.
+*/
+
+package isabelle
+
+
+object Remote_DMG
+{
+  def remote_dmg(session: SSH.Session, tar_gz_file: Path, dmg_file: Path, volume_name: String = "")
+  {
+    session.with_tmp_dir(remote_dir =>
+      using(session.sftp())(sftp =>
+        {
+          val cd = "cd " + File.bash_string(remote_dir) + "; "
+
+          sftp.write_file(remote_dir + "/dmg.tar.gz", tar_gz_file)
+          session.execute(cd + "mkdir root && tar -C root -xzf dmg.tar.gz").check
+          session.execute(
+            cd + "hdiutil create -srcfolder root" +
+              (if (volume_name == "") "" else " -volname " + File.bash_string(volume_name)) +
+              " dmg.dmg").check
+          sftp.read_file(remote_dir + "/dmg.dmg", dmg_file)
+        }))
+  }
+
+
+  /* Isabelle tool wrapper */
+
+  val isabelle_tool = Isabelle_Tool("remote_dmg", "build dmg on remote Mac OS X system", args =>
+  {
+    Command_Line.tool0 {
+      var port = SSH.default_port
+      var volume_name = ""
+
+      val getopts = Getopts("""
+Usage: isabelle remote_dmg [OPTIONS] USER@HOST TAR_GZ_FILE DMG_FILE
+
+  Options are:
+    -p PORT      alternative SSH port (default: """ + SSH.default_port + """)
+    -V NAME      specify volume name
+
+  Turn the contents of a tar.gz file into a dmg file -- produced on a remote
+  Mac OS X system.
+""",
+        "p:" -> (arg => port = Value.Int.parse(arg)),
+        "V:" -> (arg => volume_name = arg))
+
+      val more_args = getopts(args)
+      val (user, host, tar_gz_file, dmg_file) =
+        more_args match {
+          case List(SSH.User_Host(user, host), tar_gz_file, dmg_file) =>
+            (user, host, Path.explode(tar_gz_file), Path.explode(dmg_file))
+          case _ => getopts.usage()
+        }
+
+      val ssh = SSH.init(Options.init)
+      using(ssh.open_session(user = user, host = host, port = port))(
+        remote_dmg(_, tar_gz_file, dmg_file, volume_name))
+    }
+  })
+}

--- a/src/Pure/build-jars	Tue Oct 11 10:43:27 2016 +0200
+++ b/src/Pure/build-jars	Tue Oct 11 11:30:02 2016 +0200
@@ -124,6 +124,7 @@
   Tools/ml_statistics.scala
   Tools/news.scala
   Tools/print_operation.scala
+  Tools/remote_dmg.scala
   Tools/simplifier_trace.scala
   Tools/task_statistics.scala
   Tools/update_cartouches.scala