[Libguestfs] [PATCH 04/10] dib: re-read list of scripts when running in-chroot hooks

[Pino Toscano]

Scripts (especially root.d and extra-data.d) may add new scripts to the
existing set during their execution: in this case, re-read the list of
available scripts, so we do not miss any new addition.
---
 dib/dib.ml      | 14 +++++++++++++-
 dib/elements.ml | 15 +++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/dib/dib.ml b/dib/dib.ml
index 9884a7a..ff2298d 100644
--- a/dib/dib.ml
+++ b/dib/dib.ml
@@ -634,7 +634,19 @@ let main () =
 
   let run_hook ~blockdev ~sysroot ?(new_wd = "") (g : Guestfs.guestfs) hook =
     try
-      let scripts = Hashtbl.find final_hooks hook in
+      let scripts =
+        (* Sadly, scripts (especially in root.d and extra-data.d)
+         * can add (by copying or symlinking) new scripts for other
+         * phases, which would be ignored if we were using the lists
+         * collected after composing the tree of hooks.
+         * As result, when running in-chroot hooks, re-read the list
+         * of scripts actually available for each hook.
+         *)
+        match hook with
+        | "pre-install.d" | "install.d" | "post-install.d" | "finalise.d" ->
+          load_scripts g ("/tmp/aux/hooks/" ^ hook)
+        | _ ->
+          Hashtbl.find final_hooks hook in
       if debug >= 1 then (
         printf "Running hooks for %s...\n%!" hook;
       );
diff --git a/dib/elements.ml b/dib/elements.ml
index c6ca0ea..4c2875a 100644
--- a/dib/elements.ml
+++ b/dib/elements.ml
@@ -80,6 +80,21 @@ let load_hooks ~debug path =
   ) entries;
   hooks
 
+let load_scripts (g : Guestfs.guestfs) path =
+  let listing = Array.to_list (g#readdir path) in
+  let scripts = List.filter (
+    function
+    | { Guestfs.ftyp = ('r'|'l'|'u'|'?') } -> true
+    | _ -> false
+    ) listing in
+  let scripts = List.filter (fun x -> valid_script_name x.Guestfs.name) scripts in
+  filter_map (
+     fun x ->
+       let { Guestfs.st_mode = mode } = g#statns (path ^ "/" ^ x.Guestfs.name) in
+       if mode &^ 0o111_L > 0_L then Some x.Guestfs.name
+       else None
+   ) scripts
+
 let load_elements ~debug paths =
   let loaded_elements = Hashtbl.create 13 in
   let paths = List.filter is_directory paths in
-- 
2.9.3