X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=filetree.ml;h=f6ffa7b973d52a5362ae2c916e9bdb215f909df1;hb=38e0e295c438adea7a8acabd21c2fd02c236cc04;hp=2bf0b3d0cde035e7399ad545fc0354af363548f7;hpb=f09bb82de01019f24411cac2916d9567b5e9a235;p=guestfs-browser.git

diff --git a/filetree.ml b/filetree.ml
index 2bf0b3d..f6ffa7b 100644
--- a/filetree.ml
+++ b/filetree.ml
@@ -23,22 +23,62 @@ open Printf
 
 open Utils
 open DeviceSet
+open Slave_types
 
-open Filetree_type
 open Filetree_markup
-open Filetree_ops
 
 module G = Guestfs
+module UTF8 = CamomileLibraryDefault.Camomile.UTF8
 
-type t = Filetree_type.t
-
-(* Temporary directory for shared use by all instances of this widget,
- * cleaned up when the program exits.
+(* Temporary directory for shared use by any function in this file.
+ * It is cleaned up when the program exits.
  *)
 let tmpdir = tmpdir ()
 
-let rec create ~packing () =
-  let view = GTree.view ~packing () in
+(* The internal data we store attached to each row, telling us about
+ * the state of the row and what is in it.
+ *)
+type hdata = {
+  mutable state : state_t;
+  content : content_t;
+  mutable visited : bool;
+  mutable hiveh : Hivex.t option;
+}
+
+(* The type of the hidden column used to implement on-demand loading.
+ * All rows are classified as either nodes or leafs (eg. a "node" might
+ * be a directory, or a top-level operating system, or anything else
+ * which the user could open and look inside).
+ *)
+and state_t =
+  | IsLeaf           (* there are no children *)
+  | NodeNotStarted   (* user has not tried to open this *)
+  | NodeLoading      (* user tried to open it, still loading *)
+  | IsNode           (* we've loaded the children of this directory *)
+
+(* The actual content of a row. *)
+and content_t =
+  | Loading                          (* special "loading ..." node *)
+  | ErrorMessage of string           (* error message node *)
+  | Info of string                   (* information node (eg. disk usage) *)
+  | Top of Slave_types.source        (* top level OS or volume node *)
+  | TopWinReg of registry_t          (* top level Windows Registry node *)
+  | Directory of Slave_types.direntry(* a directory *)
+  | File of Slave_types.direntry     (* a file inc. special files *)
+  | RegKey of Hivex.node             (* a registry key (like a dir) *)
+  | RegValue of Hivex.value          (* a registry value (like a file) *)
+
+(* Source, root key, remote filename, cache filename *)
+and registry_t = Slave_types.source * string * string * string
+
+let source_of_registry_t (src, _, _, _) = src
+let root_key_of_registry_t (_, root_key, _, _) = root_key
+
+(* This is the Filetree.tree class, derived from GTree.view
+ * (ie. GtkTreeView).
+ *)
+class tree ?packing () =
+  let view = GTree.view ?packing () in
   (*view#set_rules_hint true;*)
   (*view#selection#set_mode `MULTIPLE; -- add this later *)
 
@@ -65,541 +105,844 @@ let rec create ~packing () =
   (* Create the model. *)
   let model = GTree.tree_store cols in
 
-  (* Create the view. *)
-  view#set_model (Some (model :> GTree.model));
-
-  let renderer = GTree.cell_renderer_text [], ["markup", mode_col] in
-  let mode_view = GTree.view_column ~title:"Permissions" ~renderer () in
-  mode_view#set_resizable true;
-  ignore (view#append_column mode_view);
-
-  let renderer = GTree.cell_renderer_text [], ["markup", name_col] in
-  let name_view = GTree.view_column ~title:"Filename" ~renderer () in
-  name_view#set_resizable true;
-  name_view#set_sizing `AUTOSIZE;
-  ignore (view#append_column name_view);
-
-  let renderer = GTree.cell_renderer_text [`XALIGN 1.], ["markup", size_col] in
-  let size_view = GTree.view_column ~title:"Size" ~renderer () in
-  size_view#set_resizable true;
-  ignore (view#append_column size_view);
-
-  let renderer = GTree.cell_renderer_text [`XALIGN 1.], ["markup", date_col] in
-  let date_view = GTree.view_column ~title:"Date" ~renderer () in
-  date_view#set_resizable true;
-  ignore (view#append_column date_view);
-
-  let t = {
-    view = view; model = model; hash = hash;
-    index_col = index_col;
-    mode_col = mode_col; name_col = name_col; size_col = size_col;
-    date_col = date_col;
-  } in
-
-  (* Open a context menu when a button is pressed. *)
-  ignore (view#event#connect#button_press ~callback:(button_press t));
-
-  t
-
-(* Handle mouse button press on the selected row.  This opens the
- * pop-up context menu.
- * http://scentric.net/tutorial/sec-selections-context-menus.html
- *)
-and button_press ({ model = model; view = view } as t) ev =
-  let button = GdkEvent.Button.button ev in
-  let x = int_of_float (GdkEvent.Button.x ev) in
-  let y = int_of_float (GdkEvent.Button.y ev) in
-  let time = GdkEvent.Button.time ev in
-
-  (* Right button for opening the context menu. *)
-  if button = 3 then (
-(*
-    (* If no row is selected, select the row under the mouse. *)
-    let paths =
-      let sel = view#selection in
-      if sel#count_selected_rows < 1 then (
-        match view#get_path_at_pos ~x ~y with
-        | None -> []
-        | Some (path, _, _, _) ->
-            sel#unselect_all ();
-            sel#select_path path;
-            [path]
-      ) else
-        sel#get_selected_rows (* actually returns paths *) in
-*)
-    (* Select the row under the mouse. *)
-    let paths =
-      let sel = view#selection in
-      match view#get_path_at_pos ~x ~y with
-      | None -> []
-      | Some (path, _, _, _) ->
-          sel#unselect_all ();
-          sel#select_path path;
-          [path] in
-
-    (* Get the hdata for all the paths.  Filter out rows that it doesn't
-     * make sense to select.
+  (* Signals. *)
+  let clear_tree = new GUtil.signal () in
+  let op_checksum_file = new GUtil.signal () in
+  let op_copy_regvalue = new GUtil.signal () in
+  let op_disk_usage = new GUtil.signal () in
+  let op_download_as_reg = new GUtil.signal () in
+  let op_download_dir_find0 = new GUtil.signal () in
+  let op_download_dir_tarball = new GUtil.signal () in
+  let op_download_file = new GUtil.signal () in
+  let op_file_information = new GUtil.signal () in
+  let op_file_properties = new GUtil.signal () in
+  let op_inspection_dialog = new GUtil.signal () in
+  let op_view_file = new GUtil.signal () in
+
+object (self)
+  inherit GTree.view view#as_tree_view
+  inherit GUtil.ml_signals [clear_tree#disconnect;
+                            op_checksum_file#disconnect;
+                            op_copy_regvalue#disconnect;
+                            op_disk_usage#disconnect;
+                            op_download_as_reg#disconnect;
+                            op_download_dir_find0#disconnect;
+                            op_download_dir_tarball#disconnect;
+                            op_download_file#disconnect;
+                            op_file_information#disconnect;
+                            op_file_properties#disconnect;
+                            op_inspection_dialog#disconnect;
+                            op_view_file#disconnect]
+
+  (* Signals. *)
+  method clear_tree : callback:(unit -> unit) -> GtkSignal.id =
+    clear_tree#connect ~after
+  method op_checksum_file = op_checksum_file#connect ~after
+  method op_copy_regvalue = op_copy_regvalue#connect ~after
+  method op_disk_usage = op_disk_usage#connect ~after
+  method op_download_as_reg = op_download_as_reg#connect ~after
+  method op_download_dir_find0 = op_download_dir_find0#connect ~after
+  method op_download_dir_tarball = op_download_dir_tarball#connect ~after
+  method op_download_file = op_download_file#connect ~after
+  method op_file_information = op_file_information#connect ~after
+  method op_file_properties = op_file_properties#connect ~after
+  method op_inspection_dialog = op_inspection_dialog#connect ~after
+  method op_view_file = op_view_file#connect ~after
+
+  initializer
+    (* Open a context menu when a button is pressed. *)
+    ignore (view#event#connect#button_press ~callback:self#button_press);
+
+    (* Create the view. *)
+    view#set_model (Some (model :> GTree.model));
+
+    (* Cell renderers. *)
+    let renderer = GTree.cell_renderer_text [], ["markup", mode_col] in
+    let mode_view = GTree.view_column ~title:"Permissions" ~renderer () in
+    mode_view#set_resizable true;
+    ignore (view#append_column mode_view);
+
+    let renderer = GTree.cell_renderer_text [], ["markup", name_col] in
+    let name_view = GTree.view_column ~title:"Filename" ~renderer () in
+    name_view#set_resizable true;
+    name_view#set_sizing `AUTOSIZE;
+    ignore (view#append_column name_view);
+
+    let renderer =
+      GTree.cell_renderer_text [`XALIGN 1.], ["markup", size_col] in
+    let size_view = GTree.view_column ~title:"Size" ~renderer () in
+    size_view#set_resizable true;
+    ignore (view#append_column size_view);
+
+    let renderer =
+      GTree.cell_renderer_text [`XALIGN 1.], ["markup", date_col] in
+    let date_view = GTree.view_column ~title:"Date" ~renderer () in
+    date_view#set_resizable true;
+    ignore (view#append_column date_view)
+
+  method clear () : unit =
+    model#clear ();
+    Hashtbl.clear hash;
+    clear_tree#call ()
+
+  method add_os name data : unit =
+    self#clear ();
+
+    (* Populate the top level of the filetree.  If there are operating
+     * systems from inspection, these have their own top level entries
+     * followed by only unreferenced filesystems.  If we didn't get
+     * anything from inspection, then at the top level we just show
+     * filesystems.
      *)
-    let paths =
-      List.filter_map (
-        fun path ->
-          let row = model#get_iter path in
-          let hdata = get_hdata t row in
-          match hdata with
-          | { content=(Loading | ErrorMessage _ | Info _) } -> None
-          | { content=(Top _ | Directory _ | File _ |
-                           TopWinReg _ | RegKey _ | RegValue _ ) } ->
-              Some (path, hdata)
-      ) paths in
-
-    (* Based on number of selected rows and what is selected, construct
-     * the context menu.
-     *)
-    (match make_context_menu t paths with
-     | Some menu -> menu#popup ~button ~time
-     | None -> ()
-    );
+    let other_filesystems =
+      DeviceSet.of_list (List.map fst data.insp_all_filesystems) in
+    let other_filesystems =
+      List.fold_left (fun set { insp_filesystems = fses } ->
+                        DeviceSet.subtract set (DeviceSet.of_array fses))
+        other_filesystems data.insp_oses in
 
-    (* Return true so no other handler will run. *)
-    true
-  )
-  (* We didn't handle this, defer to other handlers. *)
-  else false
-
-and make_context_menu t paths =
-  let menu = GMenu.menu () in
-  let factory = new GMenu.factory menu in
-
-  let rec add_file_items path =
-    let item = factory#add_item "File information" in
-    item#misc#set_sensitive false;
-    let item = factory#add_item "Checksum" in
-    item#misc#set_sensitive false;
-    ignore (factory#add_separator ());
-    let item = factory#add_item "Download ..." in
-    ignore (item#connect#activate ~callback:(download_file t path));
-
-  and add_directory_items path =
-    let item = factory#add_item "Directory information" in
-    item#misc#set_sensitive false;
-    let item = factory#add_item "Calculate disk usage" in
-    ignore (item#connect#activate ~callback:(disk_usage t path));
-    ignore (factory#add_separator ());
-    let item = factory#add_item "Download ..." in
-    item#misc#set_sensitive false;
-    let item = factory#add_item "Download as .tar ..." in
-    ignore (item#connect#activate
-              ~callback:(download_dir_tarball t Slave.Tar path));
-    let item = factory#add_item "Download as .tar.gz ..." in
-    ignore (item#connect#activate
-              ~callback:(download_dir_tarball t Slave.TGZ path));
-    let item = factory#add_item "Download as .tar.xz ..." in
-    ignore (item#connect#activate
-              ~callback:(download_dir_tarball t Slave.TXZ path));
-    let item = factory#add_item "Download list of filenames ..." in
-    ignore (item#connect#activate ~callback:(download_dir_find0 t path));
-
-  and add_top_os_items path =
-    let item = factory#add_item "Operating system information" in
-    ignore (item#connect#activate ~callback:(display_inspection_data t path));
-    ignore (factory#add_separator ());
-    add_top_volume_items path
-
-  and add_top_volume_items path =
-    let item = factory#add_item "Filesystem used & free" in
-    item#misc#set_sensitive false;
-    let item = factory#add_item "Block device information" in
-    item#misc#set_sensitive false;
-    ignore (factory#add_separator ());
-    add_directory_items path
-
-  and add_topwinreg_items path =
-    let item = factory#add_item "Download hive file ..." in
-    item#misc#set_sensitive false;
-    ignore (factory#add_separator ());
-    add_regkey_items path
-
-  and add_regkey_items path =
-    let item = factory#add_item "Download as .reg file ..." in
-    item#misc#set_sensitive false
-
-  and add_regvalue_items path =
-    let item = factory#add_item "Copy value to clipboard" in
-    ignore (item#connect#activate ~callback:(copy_regvalue t path));
-
-  in
-
-  let has_menu =
-    match paths with
-    | [] -> false
-
-    (* single selection *)
-    | [path, { content=Top (Slave.OS os)} ] ->  (* top level operating system *)
-        add_top_os_items path; true
-
-    | [path, { content=Top (Slave.Volume dev) }] -> (* top level volume *)
-        add_top_volume_items path; true
-
-    | [path, { content=Directory _ }] -> (* directory *)
-        add_directory_items path; true
-
-    | [path, { content=File _ }] ->      (* file *)
-        add_file_items path; true
-
-    | [path, { content=TopWinReg _ }] -> (* top level registry node *)
-        add_topwinreg_items path; true
-
-    | [path, { content=RegKey _ }] ->    (* registry node *)
-        add_regkey_items path; true
-
-    | [path, { content=RegValue _ }] ->  (* registry key/value pair *)
-        add_regvalue_items path; true
-
-    | [_, { content=(Loading|ErrorMessage _|Info _) }] -> false
-
-    | _::_::_ ->
-        (* At the moment multiple selection is disabled.  When/if we
-         * enable it we should do something intelligent here. XXX
-         *)
-        false in
-  if has_menu then Some menu else None
+    (* Add top level operating systems. *)
+    List.iter (self#add_top_level_os name) data.insp_oses;
 
-let clear { model = model; hash = hash } =
-  model#clear ();
-  Hashtbl.clear hash
+    (* Add top level left-over filesystems. *)
+    DeviceSet.iter (self#add_top_level_vol name) other_filesystems;
 
-let rec add ({ model = model } as t) name data =
-  clear t;
+    (* If it's Windows and registry files exist, create a node for
+     * each file.
+     *)
+    List.iter (
+      fun os ->
+        (match os.insp_winreg_SAM with
+         | Some filename ->
+             self#add_top_level_winreg name os "HKEY_LOCAL_MACHINE\\SAM"
+               filename
+         | None -> ()
+        );
+        (match os.insp_winreg_SECURITY with
+         | Some filename ->
+             self#add_top_level_winreg name os "HKEY_LOCAL_MACHINE\\SECURITY"
+               filename
+         | None -> ()
+        );
+        (match os.insp_winreg_SOFTWARE with
+         | Some filename ->
+             self#add_top_level_winreg name os "HKEY_LOCAL_MACHINE\\SOFTWARE"
+               filename
+         | None -> ()
+        );
+        (match os.insp_winreg_SYSTEM with
+         | Some filename ->
+             self#add_top_level_winreg name os "HKEY_LOCAL_MACHINE\\SYSTEM"
+               filename
+         | None -> ()
+        );
+        (match os.insp_winreg_DEFAULT with
+         | Some filename ->
+             self#add_top_level_winreg name os "HKEY_USERS\\.DEFAULT" filename
+         | None -> ()
+        );
+    ) data.insp_oses;
+
+    (* Expand the first top level node. *)
+    match model#get_iter_first with
+    | None -> ()
+    | Some row ->
+        self#expand_row (model#get_path row)
+
+  (* Add a top level operating system node. *)
+  method private add_top_level_os name os =
+    let markup =
+      sprintf "<b>%s</b>\n<small>%s</small>\n<small>%s</small>"
+        (markup_escape name) (markup_escape os.insp_hostname)
+        (markup_escape os.insp_product_name) in
+
+    let row = model#append () in
+    self#make_node row (Top (OS os)) None;
+    model#set ~row ~column:name_col markup
+
+  (* Add a top level volume (left over filesystem) node. *)
+  method private add_top_level_vol name dev =
+    let markup =
+      sprintf "<b>%s</b>\n<small>from %s</small>"
+        (markup_escape dev) (markup_escape name) in
+
+    let row = model#append () in
+    self#make_node row (Top (Volume dev)) None;
+    model#set ~row ~column:name_col markup
+
+  (* Add a top level Windows Registry node. *)
+  method private add_top_level_winreg name os rootkey remotefile =
+    let cachefile = tmpdir // string_of_int (unique ()) ^ ".hive" in
+
+    let markup =
+      sprintf "<b>%s</b>\n<small>from %s</small>"
+        (markup_escape rootkey) (markup_escape name) in
+
+    let row = model#append () in
+    self#make_node row
+      (TopWinReg (OS os, rootkey, remotefile, cachefile)) None;
+    model#set ~row ~column:name_col markup
+
+  (* Generic function to make an openable node to the tree. *)
+  method private make_node row content hiveh =
+    let hdata =
+      { state=NodeNotStarted; content=content; visited=false; hiveh=hiveh } in
+    self#store_hdata row hdata;
+
+    (* Create a placeholder "loading ..." row underneath this node so
+     * the user has something to expand.
+     *)
+    let placeholder = model#append ~parent:row () in
+    let hdata = { state=IsLeaf; content=Loading; visited=false; hiveh=None } in
+    self#store_hdata placeholder hdata;
+    model#set ~row:placeholder ~column:name_col "<i>Loading ...</i>";
+    ignore (self#connect#row_expanded ~callback:self#user_expand_row)
 
-  (* Populate the top level of the filetree.  If there are operating
-   * systems from inspection, these have their own top level entries
-   * followed by only unreferenced filesystems.  If we didn't get
-   * anything from inspection, then at the top level we just show
-   * filesystems.
-   *)
-  let other_filesystems =
-    DeviceSet.of_list (List.map fst data.Slave.insp_all_filesystems) in
-  let other_filesystems =
-    List.fold_left (fun set { Slave.insp_filesystems = fses } ->
-                      DeviceSet.subtract set (DeviceSet.of_array fses))
-      other_filesystems data.Slave.insp_oses in
+  method private make_leaf row content hiveh =
+    let hdata = { state=IsLeaf; content=content; visited=false; hiveh=hiveh } in
+    self#store_hdata row hdata
 
-  (* Add top level operating systems. *)
-  List.iter (add_top_level_os t name) data.Slave.insp_oses;
+  (* This is called when the user expands a row. *)
+  method private user_expand_row row _ =
+    match self#get_hdata row with
+    | { state=NodeNotStarted; content=Top src } as hdata ->
+        (* User has opened a top level node that was not previously opened. *)
 
-  (* Add top level left-over filesystems. *)
-  DeviceSet.iter (add_top_level_vol t name) other_filesystems;
+        (* Mark this row as loading, so we don't try to open it again. *)
+        hdata.state <- NodeLoading;
 
-  (* If it's Windows and registry files exist, create a node for
-   * each file.
-   *)
-  List.iter (
-    fun os ->
-      (match os.Slave.insp_winreg_SAM with
-       | Some filename ->
-           add_top_level_winreg t name os "HKEY_LOCAL_MACHINE\\SAM" filename
-       | None -> ()
-      );
-      (match os.Slave.insp_winreg_SECURITY with
-       | Some filename ->
-           add_top_level_winreg t name os "HKEY_LOCAL_MACHINE\\SECURITY"
-             filename
-       | None -> ()
-      );
-      (match os.Slave.insp_winreg_SOFTWARE with
-       | Some filename ->
-           add_top_level_winreg t name os "HKEY_LOCAL_MACHINE\\SOFTWARE"
-             filename
-       | None -> ()
-      );
-      (match os.Slave.insp_winreg_SYSTEM with
-       | Some filename ->
-           add_top_level_winreg t name os "HKEY_LOCAL_MACHINE\\SYSTEM"
-             filename
-       | None -> ()
-      );
-      (match os.Slave.insp_winreg_DEFAULT with
-       | Some filename ->
-           add_top_level_winreg t name os "HKEY_USERS\\.DEFAULT" filename
-       | None -> ()
-      );
-  ) data.Slave.insp_oses;
-
-  (* Expand the first top level node. *)
-  match model#get_iter_first with
-  | None -> ()
-  | Some row ->
-      t.view#expand_row (model#get_path row)
-
-(* Add a top level operating system node. *)
-and add_top_level_os ({ model = model } as t) name os =
-  let markup =
-    sprintf "<b>%s</b>\n<small>%s</small>\n<small>%s</small>"
-      (markup_escape name) (markup_escape os.Slave.insp_hostname)
-      (markup_escape os.Slave.insp_product_name) in
-
-  let row = model#append () in
-  make_node t row (Top (Slave.OS os)) None;
-  model#set ~row ~column:t.name_col markup
-
-(* Add a top level volume (left over filesystem) node. *)
-and add_top_level_vol ({ model = model } as t) name dev =
-  let markup =
-    sprintf "<b>%s</b>\n<small>from %s</small>"
-      (markup_escape dev) (markup_escape name) in
-
-  let row = model#append () in
-  make_node t row (Top (Slave.Volume dev)) None;
-  model#set ~row ~column:t.name_col markup
-
-(* Add a top level Windows Registry node. *)
-and add_top_level_winreg ({ model = model } as t) name os rootkey
-    remotefile =
-  let cachefile = tmpdir // string_of_int (unique ()) ^ ".hive" in
-
-  let markup =
-    sprintf "<b>%s</b>\n<small>from %s</small>"
-      (markup_escape rootkey) (markup_escape name) in
-
-  let row = model#append () in
-  make_node t row
-    (TopWinReg (Slave.OS os, rootkey, remotefile, cachefile)) None;
-  model#set ~row ~column:t.name_col markup
-
-(* Generic function to make an openable node to the tree. *)
-and make_node ({ model = model } as t) row content hiveh =
-  let hdata =
-    { state=NodeNotStarted; content=content; visited=false; hiveh=hiveh } in
-  store_hdata t row hdata;
-
-  (* Create a placeholder "loading ..." row underneath this node so
-   * the user has something to expand.
-   *)
-  let placeholder = model#append ~parent:row () in
-  let hdata = { state=IsLeaf; content=Loading; visited=false; hiveh=None } in
-  store_hdata t placeholder hdata;
-  model#set ~row:placeholder ~column:t.name_col "<i>Loading ...</i>";
-  ignore (t.view#connect#row_expanded ~callback:(expand_row t))
-
-and make_leaf ({ model = model } as t) row content hiveh =
-  let hdata = { state=IsLeaf; content=content; visited=false; hiveh=hiveh } in
-  store_hdata t row hdata
+        (* Get a stable path for this row. *)
+        let path = model#get_path row in
 
-(* This is called when the user expands a row. *)
-and expand_row ({ model = model } as t) row _ =
-  match get_hdata t row with
-  | { state=NodeNotStarted; content=Top src } as hdata ->
-      (* User has opened a top level node that was not previously opened. *)
+        Slave.read_directory ~fail:(self#when_read_directory_fail path)
+          src "/" (self#when_read_directory path)
 
-      (* Mark this row as loading, so we don't try to open it again. *)
-      hdata.state <- NodeLoading;
+    | { state=NodeNotStarted; content=Directory direntry } as hdata ->
+        (* User has opened a filesystem directory not previously opened. *)
 
-      (* Get a stable path for this row. *)
-      let path = model#get_path row in
+        (* Mark this row as loading. *)
+        hdata.state <- NodeLoading;
 
-      Slave.read_directory ~fail:(when_read_directory_fail t path)
-        src "/" (when_read_directory t path)
+        (* Get a stable path for this row. *)
+        let path = model#get_path row in
 
-  | { state=NodeNotStarted; content=Directory direntry } as hdata ->
-      (* User has opened a filesystem directory not previously opened. *)
+        let src, pathname = self#get_pathname row in
 
-      (* Mark this row as loading. *)
-      hdata.state <- NodeLoading;
+        Slave.read_directory ~fail:(self#when_read_directory_fail path)
+          src pathname (self#when_read_directory path)
 
-      (* Get a stable path for this row. *)
-      let path = model#get_path row in
+    | { state=NodeNotStarted;
+        content=TopWinReg topdata } as hdata ->
+        (* User has opened a Windows Registry top level node
+         * not previously opened.
+         *)
 
-      let src, pathname = get_pathname t row in
+        (* Mark this row as loading. *)
+        hdata.state <- NodeLoading;
 
-      Slave.read_directory ~fail:(when_read_directory_fail t path)
-        src pathname (when_read_directory t path)
+        (* Get a stable path for this row. *)
+        let path = model#get_path row in
 
-  | { state=NodeNotStarted;
-      content=TopWinReg (src, rootkey, remotefile, cachefile) } as hdata ->
-      (* User has opened a Windows Registry top level node
-       * not previously opened.
-       *)
+        (* Since the user has opened this top level registry node for the
+         * first time, we now need to download the hive.
+         *)
+        self#get_registry_file ~fail:(self#when_downloaded_registry_fail path)
+          path topdata (self#when_downloaded_registry path)
 
-      (* Mark this row as loading. *)
-      hdata.state <- NodeLoading;
+    | { state=NodeNotStarted; content=RegKey node } as hdata ->
+        (* User has opened a Windows Registry key node not previously opened. *)
 
-      (* Get a stable path for this row. *)
-      let path = model#get_path row in
+        (* Mark this row as loading. *)
+        hdata.state <- NodeLoading;
 
-      (* Since the user has opened this top level registry node for the
-       * first time, we now need to download the hive.
-       *)
-      Slave.download_file ~fail:(when_downloaded_registry_fail t path)
-        src remotefile cachefile (when_downloaded_registry t path)
+        self#expand_hive_node row node
 
-  | { state=NodeNotStarted; content=RegKey node } as hdata ->
-      (* User has opened a Windows Registry key node not previously opened. *)
+    (* Ignore when a user opens a node which is loading or has been loaded. *)
+    | { state=(NodeLoading|IsNode) } -> ()
 
-      (* Mark this row as loading. *)
-      hdata.state <- NodeLoading;
+    (* In some circumstances these can be nodes, eg. if we have added Info
+     * nodes below them.  Just ignore them if opened.
+     *)
+    | { content=(File _ | RegValue _) } | { state=IsLeaf } -> ()
+
+    (* Node should not exist in the tree. *)
+    | { state=NodeNotStarted; content=(Loading | ErrorMessage _ | Info _) } ->
+        assert false
+
+  (* This is the callback when the slave has read the directory for us. *)
+  method private when_read_directory path entries =
+    debug "when_read_directory";
+
+    let row = model#get_iter path in
+
+    (* Sort the entries by lexicographic ordering. *)
+    let cmp { dent_name = n1 } { dent_name = n2 } =
+      UTF8.compare n1 n2
+    in
+    let entries = List.sort ~cmp entries in
+
+    (* Add the entries. *)
+    List.iter (
+      fun direntry ->
+        let { dent_name = name; dent_stat = stat; dent_link = link } =
+          direntry in
+        let row = model#append ~parent:row () in
+        if is_directory stat.G.mode then
+          self#make_node row (Directory direntry) None
+        else
+          self#make_leaf row (File direntry) None;
+        model#set ~row ~column:name_col (markup_of_name direntry);
+        model#set ~row ~column:mode_col (markup_of_mode stat.G.mode);
+        model#set ~row ~column:size_col (markup_of_size stat.G.size);
+        model#set ~row ~column:date_col (markup_of_date stat.G.mtime);
+    ) entries;
+
+    (* Remove the placeholder "Loading" entry.  NB. Must be done AFTER
+     * adding the other entries, or else Gtk will unexpand the row.
+     *)
+    (try
+       let row = self#find_child_node_by_content row Loading in
+       ignore (model#remove row)
+     with Invalid_argument _ | Not_found -> ()
+    );
 
-      expand_hive_node t row node
+    (* The original directory entry has now been loaded, so
+     * update its state.
+     *)
+    let hdata = self#get_hdata row in
+    hdata.state <- IsNode;
+    self#set_visited row
 
-  (* Ignore when a user opens a node which is loading or has been loaded. *)
-  | { state=(NodeLoading|IsNode) } -> ()
+  (* This is called instead of when_read_directory when the read directory
+   * (or mount etc) failed.  Convert the "Loading" entry into the
+   * error message.
+   *)
+  method private when_read_directory_fail path exn =
+    debug "when_read_directory_fail: %s" (Printexc.to_string exn);
 
-  (* These are not nodes so it should never be possible to open them. *)
-  | { content=(File _ | RegValue _) } | { state=IsLeaf } -> assert false
+    match exn with
+    | G.Error msg ->
+        let row = model#get_iter path in
+        let row = model#iter_children ~nth:0 (Some row) in
 
-  (* Node should not exist in the tree. *)
-  | { state=NodeNotStarted; content=(Loading | ErrorMessage _ | Info _) } ->
-      assert false
+        let hdata =
+          { state=IsLeaf; content=ErrorMessage msg;
+            visited=false; hiveh=None } in
+        self#store_hdata row hdata;
 
-(* This is the callback when the slave has read the directory for us. *)
-and when_read_directory ({ model = model } as t) path entries =
-  debug "when_read_directory";
+        model#set ~row ~column:name_col (markup_escape msg)
 
-  let row = model#get_iter path in
+    | exn ->
+        (* unexpected exception: re-raise it *)
+        raise exn
 
-  (* Sort the entries by lexicographic ordering. *)
-  let cmp { Slave.dent_name = n1 } { Slave.dent_name = n2 } =
-    UTF8.compare n1 n2
-  in
-  let entries = List.sort ~cmp entries in
+  (* Called when the top level registry node has been opened and the
+   * hive file was downloaded to the cache file successfully.
+   *)
+  method private when_downloaded_registry path _ =
+    debug "when_downloaded_registry";
+    let row = model#get_iter path in
+    let hdata = self#get_hdata row in
+    let h = Option.get hdata.hiveh in
+
+    (* Continue as if expanding any other hive node. *)
+    let root = Hivex.root h in
+    self#expand_hive_node row root
+
+  (* Called instead of {!when_downloaded_registry} if the download failed. *)
+  method private when_downloaded_registry_fail path exn =
+    debug "when_downloaded_registry_fail: %s" (Printexc.to_string exn);
+
+    match exn with
+    | G.Error msg
+    | Hivex.Error (_, _, msg) ->
+        let row = model#get_iter path in
+        let row = model#iter_children ~nth:0 (Some row) in
+
+        let hdata =
+          { state=IsLeaf; content=ErrorMessage msg;
+            visited=false; hiveh=None } in
+        self#store_hdata row hdata;
+
+        model#set ~row ~column:name_col (markup_escape msg)
+
+    | exn ->
+        (* unexpected exception: re-raise it *)
+        raise exn
+
+  (* Expand a hive node. *)
+  method private expand_hive_node row node =
+    debug "expand_hive_node";
+    let hdata = self#get_hdata row in
+    let h = Option.get hdata.hiveh in
+
+    (* Read the hive entries (values, subkeys) at this node and add them
+     * to the tree.
+     *)
+    let values = Hivex.node_values h node in
+    let cmp v1 v2 =
+      UTF8.compare (Hivex.value_key h v1) (Hivex.value_key h v2)
+    in
+    Array.sort cmp values;
+    Array.iter (
+      fun value ->
+        let row = model#append ~parent:row () in
+        self#make_leaf row (RegValue value) (Some h);
+        model#set ~row ~column:name_col (markup_of_regvalue h value);
+        model#set ~row ~column:size_col (markup_of_regvaluesize h value);
+        model#set ~row ~column:date_col (markup_of_regvaluetype h value);
+    ) values;
+
+    let children = Hivex.node_children h node in
+    let cmp n1 n2 =
+      UTF8.compare (Hivex.node_name h n1) (Hivex.node_name h n2)
+    in
+    Array.sort cmp children;
+    Array.iter (
+      fun node ->
+        let row = model#append ~parent:row () in
+        self#make_node row (RegKey node) (Some h);
+        model#set ~row ~column:name_col (markup_of_regkey h node);
+    ) children;
+
+    (* Remove the placeholder "Loading" entry.  NB. Must be done AFTER
+     * adding the other entries, or else Gtk will unexpand the row.
+     *)
+    (try
+       let row = self#find_child_node_by_content row Loading in
+       ignore (model#remove row)
+     with Invalid_argument _ | Not_found -> ()
+    );
 
-  (* Add the entries. *)
-  List.iter (
-    fun direntry ->
-      let { Slave.dent_name = name; dent_stat = stat; dent_link = link } =
-        direntry in
-      let row = model#append ~parent:row () in
-      if is_directory stat.G.mode then
-        make_node t row (Directory direntry) None
-      else
-        make_leaf t row (File direntry) None;
-      model#set ~row ~column:t.name_col (markup_of_name direntry);
-      model#set ~row ~column:t.mode_col (markup_of_mode stat.G.mode);
-      model#set ~row ~column:t.size_col (markup_of_size stat.G.size);
-      model#set ~row ~column:t.date_col (markup_of_date stat.G.mtime);
-  ) entries;
-
-  (* Remove the placeholder "Loading" entry.  NB. Must be done AFTER
-   * adding the other entries, or else Gtk will unexpand the row.
+    (* The original entry has now been loaded, so update its state. *)
+    hdata.state <- IsNode;
+    self#set_visited row
+
+  (* Return os(es) in the tree, if any.  The root directory of the
+   * tree looks like this:
+   *
+   *  \ Top (OS ...)   # usually only one, but there can be zero or > 1
+   *  \ Top (OS ...)
+   *  \ Top (Volume ...)
+   *  \ TopWinReg
+   *  \ TopWinReg
+   *
+   * This returns only the Top (OS ...) entries.  See also #add_top_level_os
+   * method.
    *)
-  (try
-     let row = find_child_node_by_content t row Loading in
-     ignore (model#remove row)
-   with Invalid_argument _ | Not_found -> ()
-  );
-
-  (* The original directory entry has now been loaded, so
-   * update its state.
+  method oses =
+    match model#get_iter_first with
+    | None -> []
+    | Some row ->
+        let rec loop acc =
+          let acc =
+            match (self#get_hdata row).content with
+            | Top (OS os) -> os :: acc
+            | _ -> acc in
+          if model#iter_next row then
+            loop acc
+          else
+            List.rev acc
+        in
+        loop []
+
+  (* Handle mouse button press on the selected row.  This opens the
+   * pop-up context menu.
+   * http://scentric.net/tutorial/sec-selections-context-menus.html
    *)
-  let hdata = get_hdata t row in
-  hdata.state <- IsNode;
-  set_visited t row
-
-(* This is called instead of when_read_directory when the read directory
- * (or mount etc) failed.  Convert the "Loading" entry into the
- * error message.
- *)
-and when_read_directory_fail ({ model = model } as t) path exn =
-  debug "when_read_directory_fail: %s" (Printexc.to_string exn);
-
-  match exn with
-  | G.Error msg ->
-      let row = model#get_iter path in
-      let row = model#iter_children ~nth:0 (Some row) in
-
-      let hdata =
-        { state=IsLeaf; content=ErrorMessage msg; visited=false; hiveh=None } in
-      store_hdata t row hdata;
-
-      model#set ~row ~column:t.name_col (markup_escape msg)
+  method private button_press ev =
+    let button = GdkEvent.Button.button ev in
+    let x = int_of_float (GdkEvent.Button.x ev) in
+    let y = int_of_float (GdkEvent.Button.y ev) in
+    let time = GdkEvent.Button.time ev in
+
+    (* Right button for opening the context menu. *)
+    if button = 3 then (
+(*
+    (* If no row is selected, select the row under the mouse. *)
+    let paths =
+      let sel = view#selection in
+      if sel#count_selected_rows < 1 then (
+        match view#get_path_at_pos ~x ~y with
+        | None -> []
+        | Some (path, _, _, _) ->
+            sel#unselect_all ();
+            sel#select_path path;
+            [path]
+      ) else
+        sel#get_selected_rows (* actually returns paths *) in
+*)
+      (* Select the row under the mouse. *)
+      let paths =
+        let sel = view#selection in
+        match view#get_path_at_pos ~x ~y with
+        | None -> []
+        | Some (path, _, _, _) ->
+            sel#unselect_all ();
+            sel#select_path path;
+            [path] in
 
-  | exn ->
-      (* unexpected exception: re-raise it *)
-      raise exn
+      (* Get the hdata for all the paths.  Filter out rows that it doesn't
+       * make sense to select.
+       *)
+      let paths =
+        List.filter_map (
+          fun path ->
+            let row = model#get_iter path in
+            let hdata = self#get_hdata row in
+            match hdata with
+            | { content=(Loading | ErrorMessage _ | Info _) } -> None
+            | { content=(Top _ | Directory _ | File _ |
+                             TopWinReg _ | RegKey _ | RegValue _ ) } ->
+                Some (path, hdata)
+        ) paths in
+
+      (* Based on number of selected rows and what is selected, construct
+       * the context menu.
+       *)
+      (match self#make_context_menu paths with
+       | Some menu -> menu#popup ~button ~time
+       | None -> ()
+      );
 
-(* Called when the top level registry node has been opened and the
- * hive file was downloaded to the cache file successfully.
- *)
-and when_downloaded_registry ({ model = model } as t) path () =
-  debug "when_downloaded_registry";
-  let row = model#get_iter path in
-
-  let hdata = get_hdata t row in
-  match hdata.content with
-  | TopWinReg (src, rootkey, remotefile, cachefile) ->
-      (try
-         (* Open the hive and save the hive handle in the row hdata. *)
-         let flags = if verbose () then [ Hivex.OPEN_VERBOSE ] else [] in
-         let h = Hivex.open_file cachefile flags in
-         hdata.hiveh <- Some h;
-
-         (* Continue as if expanding any other hive node. *)
-         let root = Hivex.root h in
-         expand_hive_node t row root
-       with
-         Hivex.Error _ as exn -> when_downloaded_registry_fail t path exn
+      (* Return true so no other handler will run. *)
+      true
+    )
+    (* We didn't handle this, defer to other handlers. *)
+    else false
+
+  method private make_context_menu paths =
+    let menu = GMenu.menu () in
+    let factory = new GMenu.factory menu in
+
+    let rec add_file_items path =
+      let item = factory#add_item "View ..." in
+      (match Config.opener with
+       | Some opener ->
+           ignore (item#connect#activate
+                     ~callback:(fun () -> op_view_file#call (path, opener)));
+       | None ->
+           item#misc#set_sensitive false
+      );
+      let item = factory#add_item "File information" in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_file_information#call path));
+      let item = factory#add_item "MD5 checksum" in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_checksum_file#call (path, "md5")));
+      let item = factory#add_item "SHA1 checksum" in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_checksum_file#call (path, "sha1")));
+      ignore (factory#add_separator ());
+      let item = factory#add_item "Download ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_download_file#call path));
+      ignore (factory#add_separator ());
+      let item = factory#add_item "Properties ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_file_properties#call path))
+
+    and add_directory_items path =
+      let item = factory#add_item "Directory information" in
+      item#misc#set_sensitive false;
+      let item = factory#add_item "Calculate disk usage" in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_disk_usage#call path));
+      ignore (factory#add_separator ());
+      let item = factory#add_item "Download ..." in
+      item#misc#set_sensitive false;
+      let item = factory#add_item "Download as .tar ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_download_dir_tarball#call (Tar, path)));
+      let item = factory#add_item "Download as .tar.gz ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_download_dir_tarball#call (TGZ, path)));
+      let item = factory#add_item "Download as .tar.xz ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_download_dir_tarball#call (TXZ, path)));
+      let item = factory#add_item "Download list of filenames ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_download_dir_find0#call path));
+      ignore (factory#add_separator ());
+      let item = factory#add_item "Properties ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_file_properties#call path))
+
+    and add_top_os_items os path =
+      let item = factory#add_item "Operating system information ..." in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_inspection_dialog#call os));
+      ignore (factory#add_separator ());
+      add_top_volume_items path
+
+    and add_top_volume_items path =
+      let item = factory#add_item "Filesystem used & free" in
+      item#misc#set_sensitive false;
+      let item = factory#add_item "Block device information" in
+      item#misc#set_sensitive false;
+      ignore (factory#add_separator ());
+      add_directory_items path
+
+    and add_topwinreg_items path =
+      let item = factory#add_item "Download hive file ..." in
+      item#misc#set_sensitive false;
+      ignore (factory#add_separator ());
+      add_regkey_items path
+
+    and add_regkey_items path =
+      let item = factory#add_item "Download as .reg file ..." in
+      (match Config.hivexregedit with
+       | Some hivexregedit ->
+           ignore (item#connect#activate
+                     ~callback:(fun () ->
+                                op_download_as_reg#call (path, hivexregedit)));
+       | None ->
+           item#misc#set_sensitive false
       )
-  | _ -> assert false
-
-(* Called instead of {!when_downloaded_registry} if the download failed. *)
-and when_downloaded_registry_fail ({ model = model } as t) path exn =
-  debug "when_downloaded_registry_fail: %s" (Printexc.to_string exn);
-
-  match exn with
-  | G.Error msg
-  | Hivex.Error (_, _, msg) ->
-      let row = model#get_iter path in
-      let row = model#iter_children ~nth:0 (Some row) in
-
-      let hdata =
-        { state=IsLeaf; content=ErrorMessage msg; visited=false; hiveh=None } in
-      store_hdata t row hdata;
 
-      model#set ~row ~column:t.name_col (markup_escape msg)
-
-  | exn ->
-      (* unexpected exception: re-raise it *)
-      raise exn
-
-(* Expand a hive node. *)
-and expand_hive_node ({ model = model } as t) row node =
-  debug "expand_hive_node";
-  let hdata = get_hdata t row in
-  let h = Option.get hdata.hiveh in
-
-  (* Read the hive entries (values, subkeys) at this node and add them
-   * to the tree.
+    and add_regvalue_items path =
+      let item = factory#add_item "Copy value to clipboard" in
+      ignore (item#connect#activate
+                ~callback:(fun () -> op_copy_regvalue#call path));
+
+    in
+
+    let has_menu =
+      match paths with
+      | [] -> false
+
+      (* single selection *)
+      | [path, { content=Top (OS os)} ] ->  (* top level operating system *)
+          add_top_os_items os path; true
+
+      | [path, { content=Top (Volume dev) }] -> (* top level volume *)
+          add_top_volume_items path; true
+
+      | [path, { content=Directory _ }] -> (* directory *)
+          add_directory_items path; true
+
+      | [path, { content=File _ }] ->      (* file *)
+          add_file_items path; true
+
+      | [path, { content=TopWinReg _ }] -> (* top level registry node *)
+          add_topwinreg_items path; true
+
+      | [path, { content=RegKey _ }] ->    (* registry node *)
+          add_regkey_items path; true
+
+      | [path, { content=RegValue _ }] ->  (* registry key/value pair *)
+          add_regvalue_items path; true
+
+      | [_, { content=(Loading|ErrorMessage _|Info _) }] -> false
+
+      | _::_::_ ->
+          (* At the moment multiple selection is disabled.  When/if we
+           * enable it we should do something intelligent here. XXX
+           *)
+          false in
+    if has_menu then Some menu else None
+
+  (* Store hdata into a row. *)
+  method private store_hdata row hdata =
+    let index = unique () in
+    Hashtbl.add hash index hdata;
+    model#set ~row ~column:index_col index
+
+  (* Retrieve previously stored hdata from a row. *)
+  method private get_hdata row =
+    let index = model#get ~row ~column:index_col in
+    try Hashtbl.find hash index
+    with Not_found -> assert false
+
+  (* [find_child_node_by_content row content] searches the direct
+     children of [row] looking for one which exactly matches
+     [hdata.content] and returns that child.  If no child found,
+     raises [Not_found]. *)
+  method private find_child_node_by_content row c =
+    let rec loop row =
+      if (self#get_hdata row).content = c then
+        row
+      else if model#iter_next row then
+        loop row
+      else
+        raise Not_found
+    in
+
+    if not (model#iter_has_child row) then
+      raise Not_found;
+
+    let first_child = model#iter_children (Some row) in
+    loop first_child
+
+  (* Search up to the top of the tree so we know if this directory
+   * comes from an OS or a volume, and the full path to here.
+   *
+   * The path up the tree will always look something like:
+   *     Top
+   *       \_ Directory
+   *            \_ Directory
+   *                 \_ Loading    <--- you are here
+   *
+   * Note this function cannot be called on registry keys.  See
+   * {!get_registry_path} for that.
+   *)
+  method get_pathname row =
+    let hdata = self#get_hdata row in
+    let parent = model#iter_parent row in
+
+    match hdata, parent with
+    | { state=IsLeaf; content=(Loading|ErrorMessage _|Info _) }, Some parent ->
+        self#get_pathname parent
+    | { state=IsLeaf; content=(Loading|ErrorMessage _|Info _) }, None ->
+        assert false
+    | { content=Directory { dent_name = name }}, Some parent
+    | { content=File { dent_name = name }}, Some parent ->
+        let src, parent_name = self#get_pathname parent in
+        let path =
+          if parent_name = "/" then "/" ^ name
+          else parent_name ^ "/" ^ name in
+        src, path
+    | { content=Top src }, _ -> src, "/"
+    | { content=Directory _ }, None -> assert false
+    | { content=File _ }, None -> assert false
+    | { content=Loading }, _ -> assert false
+    | { content=ErrorMessage _ }, _ -> assert false
+    | { content=Info _ }, _ -> assert false
+    | { content=TopWinReg _ }, _ -> assert false
+    | { content=RegKey _ }, _ -> assert false
+    | { content=RegValue _ }, _ -> assert false
+
+  method get_direntry row =
+    let hdata = self#get_hdata row in
+    match hdata with
+    | { content=Directory direntry}
+    | { content=File direntry}      -> direntry
+    | _ -> assert false
+
+  (* Search up to the top of the tree from a registry key.
+   *
+   * The path up the tree will always look something like:
+   *     TopWinReg
+   *       \_ RegKey
+   *            \_ RegKey          <--- you are here
+   *                 \_ Loading    <--- or here
+   *
+   * Note this function cannot be called on ordinary paths.  Use
+   * {!get_pathname} for that.
    *)
-  let values = Hivex.node_values h node in
-  let cmp v1 v2 = UTF8.compare (Hivex.value_key h v1) (Hivex.value_key h v2) in
-  Array.sort cmp values;
-  Array.iter (
-    fun value ->
-      let row = model#append ~parent:row () in
-      make_leaf t row (RegValue value) (Some h);
-      model#set ~row ~column:t.name_col (markup_of_regvalue h value);
-      model#set ~row ~column:t.size_col (markup_of_regvaluesize h value);
-      model#set ~row ~column:t.date_col (markup_of_regvaluetype h value);
-  ) values;
-
-  let children = Hivex.node_children h node in
-  let cmp n1 n2 = UTF8.compare (Hivex.node_name h n1) (Hivex.node_name h n2) in
-  Array.sort cmp children;
-  Array.iter (
-    fun node ->
-      let row = model#append ~parent:row () in
-      make_node t row (RegKey node) (Some h);
-      model#set ~row ~column:t.name_col (markup_of_regkey h node);
-  ) children;
-
-  (* Remove the placeholder "Loading" entry.  NB. Must be done AFTER
-   * adding the other entries, or else Gtk will unexpand the row.
+  method get_registry_path row =
+    let hdata = self#get_hdata row in
+    let parent = model#iter_parent row in
+
+    match hdata, parent with
+    | { state=IsLeaf; content=(Loading|ErrorMessage _|Info _) }, Some parent ->
+        self#get_registry_path parent
+    | { state=IsLeaf; content=(Loading|ErrorMessage _|Info _) }, None ->
+        assert false
+    | { content=RegKey node; hiveh = Some h }, Some parent ->
+        let top, path = self#get_registry_path parent in
+        let path = Hivex.node_name h node :: path in
+        top, path
+    | { content=TopWinReg (a,b,c,d) }, None -> (a,b,c,d), []
+    | { content=TopWinReg _ }, _ -> assert false
+    | { content=RegKey _}, _ -> assert false
+    | { content=Top _ }, _ -> assert false
+    | { content=Directory _ }, _ -> assert false
+    | { content=File _ }, _ -> assert false
+    | { content=Loading }, _ -> assert false
+    | { content=ErrorMessage _ }, _ -> assert false
+    | { content=Info _ }, _ -> assert false
+    | { content=RegValue _ }, _ -> assert false
+
+  method get_registry_value row =
+    let hdata = self#get_hdata row in
+    match hdata with
+    | { content=RegValue value; hiveh = Some h } ->
+        Hivex.value_value h value
+    | _ -> assert false (* not a registry value *)
+
+  (* This is called whenever we need the registry cache file and we
+     can't be sure that it has already been downloaded. *)
+  method get_registry_file ?fail path (src, _, remotefile, cachefile) cb =
+    let row = model#get_iter path in
+    let top =
+      let rec loop row =
+        match model#iter_parent row with
+        | None -> row
+        | Some parent -> loop parent
+      in
+      loop row in
+
+    Slave.download_file_if_not_exist ?fail src remotefile cachefile
+      (self#when_got_registry_file ?fail top cb)
+
+  method private when_got_registry_file ?fail top cb () =
+    debug "when_got_registry_file";
+    let hdata = self#get_hdata top in
+
+    match hdata with
+    | { hiveh=Some _; content=TopWinReg (_, _, _, cachefile) } ->
+        (* Hive handle already opened. *)
+        cb cachefile
+
+    | { hiveh=None; content=TopWinReg (src, rootkey, remotefile, cachefile) } ->
+        (* Hive handle not opened, open it and save it in the handle. *)
+        (try
+           let flags = if verbose () then [ Hivex.OPEN_VERBOSE ] else [] in
+           let h = Hivex.open_file cachefile flags in
+           hdata.hiveh <- Some h;
+           cb cachefile
+         with
+           Hivex.Error _ as exn ->
+             match fail with
+             | Some fail -> fail exn
+             | None -> raise exn
+        )
+
+    | _ -> assert false
+
+  (* This is a bit of a hack.  Ideally just setting 'visited' would
+   * darken the colour when the cell was re-rendered.  However that would
+   * mean we couldn't store other stuff in the name column.  Therefore,
+   * repopulate the name column.
    *)
-  (try
-     let row = find_child_node_by_content t row Loading in
-     ignore (model#remove row)
-   with Invalid_argument _ | Not_found -> ()
-  );
-
-  (* The original entry has now been loaded, so update its state. *)
-  hdata.state <- IsNode;
-  set_visited t row
+  method set_visited row =
+    let hdata = self#get_hdata row in
+    if hdata.visited = false then (
+      hdata.visited <- true;
+      match hdata.content with
+      | Directory direntry | File direntry ->
+          debug "set_visited %s" direntry.dent_name;
+          model#set ~row ~column:name_col
+            (markup_of_name ~visited:true direntry)
+      | RegKey node ->
+          debug "set_visited RegKey";
+          let h = Option.get hdata.hiveh in
+          model#set ~row ~column:name_col
+            (markup_of_regkey ~visited:true h node)
+      | RegValue value ->
+          debug "set_visited RegValue";
+          let h = Option.get hdata.hiveh in
+          model#set ~row ~column:name_col
+            (markup_of_regvalue ~visited:true h value)
+      | Loading | ErrorMessage _ | Info _ | Top _ | TopWinReg _ -> ()
+    )
+
+  method has_child_info_node path info_text =
+    let row = model#get_iter path in
+    let content = Info info_text in
+    try ignore (self#find_child_node_by_content row content); true
+    with Not_found -> false
+
+  method set_child_info_node path info_text text =
+    self#expand_row path;
+    let row = model#get_iter path in
+    let content = Info info_text in
+    let row =
+      try self#find_child_node_by_content row content
+      with Not_found -> model#insert ~parent:row 0 in
+    let hdata = { state=IsLeaf; content=content; visited=false; hiveh=None } in
+    self#store_hdata row hdata;
+    model#set ~row ~column:name_col text
+
+end