1 files changed, 59 insertions, 0 deletions
diff --git a/src/session.ml b/src/session.ml
index 03c5f91..44feb8f 100644
--- a/src/session.ml
+++ b/src/session.ml
@@ -34,6 +34,7 @@ type session_data = {
     conf_mode: bool;
     changeset: cfg_op list;
     mutable aux_changeset: aux_op list;
+    edit_level: string list;
     client_app: string;
     client_pid: int32;
     client_user: string;
@@ -45,6 +46,7 @@ let make _world client_app sudo_user user pid = {
     conf_mode = false;
     changeset = [];
     aux_changeset = [];
+    edit_level = [];
     client_app = client_app;
     client_user = user;
     client_sudo_user = sudo_user;
@@ -262,6 +264,63 @@ let aux_delete w s path name tagval =
 let discard _w s =
     { s with changeset = []; }
 
+let edit_env_str s =
+    (* To maintain consistency with classic CLI, we return env variable for
+       PS1 on changes to edit level.
+     *)
+    let ps1 =
+    match s.edit_level with
+    | [] ->
+        "[edit]\\n\\u@\\H${VRF:+(vrf:$VRF)}${NETNS:+(ns:$NETNS)}# "
+    | _ as p ->
+        Printf.sprintf
+        "[edit %s]\\n\\u@\\H${VRF:+(vrf:$VRF)}${NETNS:+(ns:$NETNS)}# "
+        (Vyos1x.Util.string_of_list p)
+    in
+    Printf.sprintf "export PS1='%s';" ps1
+
+let set_edit_level w s path =
+    let current_level = s.edit_level in
+    let new_level = current_level @ path in
+    let result = RT.allowed_edit_level w.reference_tree new_level in
+    match result with
+    | Ok () ->
+        let c = get_proposed_config w s in
+        let s' =
+            if not ((VT.exists[@alert "-exn"]) c path) then
+                set w s path
+            else s
+        in
+        let session = { s' with edit_level = new_level; } in
+        session, (edit_env_str session)
+    | Error msg ->
+        raise (Session_error msg)
+
+let set_edit_level_up w s =
+    let current_level = s.edit_level in
+    let new_level =
+        if Vyos1x.Util.is_empty current_level then
+            current_level
+        else
+        let up = Vyos1x.Util.drop_last current_level in
+        match RT.allowed_edit_level w.reference_tree up with
+        | Ok () -> up
+        | Error _ -> (* tag_value *)
+            Vyos1x.Util.drop_last up
+    in
+    let session = { s with edit_level = new_level; }
+    in session, (edit_env_str session)
+
+let get_edit_level _w s =
+    Vyos1x.Util.string_of_list s.edit_level
+
+let reset_edit_level _w s =
+    let session = { s with edit_level = []; }
+    in session, (edit_env_str session)
+
+let edit_level_root _w s =
+    Vyos1x.Util.is_empty s.edit_level
+
 let session_changed w s =
     (* structural equality test requires consistent ordering, which is
      * practised, but may be unreliable; test actual difference