[Libguestfs] [PATCH 1/5] dib: implement get_image_element_array stuff

[Pino Toscano]

Output the get_image_element_array function like d-i-b does, together
with the eval stuff needed to make it work.

get_image_element_array is basically a bash array, with the keys are the
used elements, and the values are the paths of each element; it is a new
addition in d-i-b 2.0.

This is used so far only for the extra-data.d phase.
---
 dib/dib.ml | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/dib/dib.ml b/dib/dib.ml
index 2e4da4b..0d128e3 100644
--- a/dib/dib.ml
+++ b/dib/dib.ml
@@ -74,9 +74,15 @@ let envvars_string l =
 
 let prepare_external ~envvars ~dib_args ~dib_vars ~out_name ~root_label
   ~rootfs_uuid ~image_cache ~arch ~network ~debug ~fs_type ~checksum
-  destdir libdir fakebindir all_elements element_paths =
+  destdir libdir fakebindir loaded_elements all_elements element_paths =
   let network_string = if network then "" else "1" in
   let checksum_string = if checksum then "1" else "" in
+  let elements_paths_array =
+    List.map (
+      fun e ->
+        sprintf "[%s]=%s" e (quote (Hashtbl.find loaded_elements e).directory)
+    ) (StringSet.elements all_elements) in
+  let elements_paths_array = String.concat " " elements_paths_array in
 
   let run_extra = sprintf "\
 #!/bin/bash
@@ -91,6 +97,8 @@ shift
 script=$1
 shift
 
+VIRT_DIB_OURPATH=$(dirname $(realpath $0))
+
 # user variables
 %s
 
@@ -116,6 +124,9 @@ export DIB_DEBUG_TRACE=%d
 export FS_TYPE=%s
 export DIB_CHECKSUM=%s
 
+elinfo_out=$(<${VIRT_DIB_OURPATH}/elinfo_out)
+eval \"$elinfo_out\"
+
 ENVIRONMENT_D_DIR=$target_dir/../environment.d
 
 if [ -d $ENVIRONMENT_D_DIR ] ; then
@@ -148,7 +159,15 @@ $target_dir/$script
     debug
     fs_type
     checksum_string in
-  write_script (destdir // "run-part-extra.sh") run_extra
+  write_script (destdir // "run-part-extra.sh") run_extra;
+  let elinfo_out = sprintf "\
+function get_image_element_array {
+  echo \"%s\"
+};
+export -f get_image_element_array;
+"
+    elements_paths_array in
+  write_script (destdir // "elinfo_out") elinfo_out
 
 let prepare_aux ~envvars ~dib_args ~dib_vars ~log_file ~out_name ~rootfs_uuid
   ~arch ~network ~root_label ~install_type ~debug ~extra_packages ~fs_type
@@ -636,7 +655,7 @@ let main () =
                    ~checksum:cmdline.checksum
                    tmpdir cmdline.basepath
                    (auxtmpdir // "fake-bin")
-                   all_elements cmdline.element_paths;
+                   loaded_elements all_elements cmdline.element_paths;
 
   let run_hook ~blockdev ~sysroot ?(new_wd = "") (g : Guestfs.guestfs) hook =
     try
-- 
2.9.3