From 5fa16cde0a4eca12346247ece1a3d24e2748ab79 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bob=20Dr=C3=B6ge?= <b.e.droge@rug.nl>
Date: Fri, 21 Nov 2025 15:06:42 +0100
Subject: [PATCH 1/4] find the oldest EESSI version and use its Lmod cache
 update script for any version

---
 scripts/ingest-tarball.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/scripts/ingest-tarball.sh b/scripts/ingest-tarball.sh
index 9a2580d2..c5b53ce4 100755
--- a/scripts/ingest-tarball.sh
+++ b/scripts/ingest-tarball.sh
@@ -182,6 +182,9 @@ function update_lmod_caches() {
         error "the script for updating the Lmod caches (${update_caches_script}) does not have execute permissions!"
     fi
     ${cvmfs_server} transaction "${cvmfs_repo}"
+    # Find the oldest version that we have, and use its Lmod to generate the cache to get better backwards compatibilty with old Lmod versions
+    oldest_stack=$(ls -1 -v "${CVMFS_ROOT}/${cvmfs_repo}/${basedir}" | head -n 1)
+    oldest_stack_lmod_update_script="${CVMFS_ROOT}/${cvmfs_repo}/${basedir}/${oldest_stack}/compat/linux/$(uname -m)/usr/share/Lmod/libexec/update_lmod_system_cache_files"
     ${update_caches_script} "${CVMFS_ROOT}/${cvmfs_repo}/${basedir}/${version}"
     ec=$?
     if [ $ec -eq 0 ]; then

From dd1ce43727e4f6791ebfc27aac9a3913141173f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bob=20Dr=C3=B6ge?= <b.e.droge@rug.nl>
Date: Fri, 21 Nov 2025 15:06:52 +0100
Subject: [PATCH 2/4] allow overriding of the Lmod cache update script location

---
 scripts/update_lmod_caches.sh | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/scripts/update_lmod_caches.sh b/scripts/update_lmod_caches.sh
index 70737123..a1826edc 100755
--- a/scripts/update_lmod_caches.sh
+++ b/scripts/update_lmod_caches.sh
@@ -14,11 +14,12 @@ function error() {
 }
 
 # Check if a stack base dir has been specified
-if [ "$#" -ne 1 ]; then
+if [ "$#" -lt 1 ] || [ "$#" -gt 2 ]; then
     error "usage: $0 <path to main directory of an EESSI stack>"
 fi
 
 stack_base_dir="$1"
+update_lmod_system_cache_files="$2"
 
 # Check if the given stack base dir exists
 if [ ! -d ${stack_base_dir} ]
@@ -26,8 +27,11 @@ then
   error "${stack_base_dir} does not point to an existing directory!"
 fi
 
-# Check if Lmod's cache update script can be found at the expected location (in the compatibility layer of the given stack)
-update_lmod_system_cache_files="${stack_base_dir}/compat/linux/$(uname -m)/usr/share/Lmod/libexec/update_lmod_system_cache_files"
+# If no Lmod cache update script was specified, try to find one in the compatibility layer of the given stack
+if [ -z ${update_lmod_system_cache_files} ]; then
+  update_lmod_system_cache_files="${stack_base_dir}/compat/linux/$(uname -m)/usr/share/Lmod/libexec/update_lmod_system_cache_files"
+fi
+# Make sure that the expected Lmod cache update script exists
 if [ ! -f ${update_lmod_system_cache_files} ]
 then
   error "expected to find Lmod's cache update script at ${update_lmod_system_cache_files}, but it doesn't exist."

From 431d1ae8523021cc413661dc100da762bb3a2b5d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bob=20Dr=C3=B6ge?= <b.e.droge@rug.nl>
Date: Fri, 21 Nov 2025 15:14:21 +0100
Subject: [PATCH 3/4] actually pass oldest_stack_lmod_update_script as argument

---
 scripts/ingest-tarball.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/ingest-tarball.sh b/scripts/ingest-tarball.sh
index c5b53ce4..952c8629 100755
--- a/scripts/ingest-tarball.sh
+++ b/scripts/ingest-tarball.sh
@@ -185,7 +185,7 @@ function update_lmod_caches() {
     # Find the oldest version that we have, and use its Lmod to generate the cache to get better backwards compatibilty with old Lmod versions
     oldest_stack=$(ls -1 -v "${CVMFS_ROOT}/${cvmfs_repo}/${basedir}" | head -n 1)
     oldest_stack_lmod_update_script="${CVMFS_ROOT}/${cvmfs_repo}/${basedir}/${oldest_stack}/compat/linux/$(uname -m)/usr/share/Lmod/libexec/update_lmod_system_cache_files"
-    ${update_caches_script} "${CVMFS_ROOT}/${cvmfs_repo}/${basedir}/${version}"
+    ${update_caches_script} "${CVMFS_ROOT}/${cvmfs_repo}/${basedir}/${version}" "${oldest_stack_lmod_update_script}"
     ec=$?
     if [ $ec -eq 0 ]; then
         ${cvmfs_server} publish -m "update Lmod caches after ingesting ${tar_file_basename}" "${cvmfs_repo}"

From 6f3e6b5ba0721e3cd7f7704254abd3db82a25953 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bob=20Dr=C3=B6ge?= <b.e.droge@rug.nl>
Date: Fri, 21 Nov 2025 15:16:37 +0100
Subject: [PATCH 4/4] update usage info

---
 scripts/update_lmod_caches.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/update_lmod_caches.sh b/scripts/update_lmod_caches.sh
index a1826edc..79ba632d 100755
--- a/scripts/update_lmod_caches.sh
+++ b/scripts/update_lmod_caches.sh
@@ -15,7 +15,7 @@ function error() {
 
 # Check if a stack base dir has been specified
 if [ "$#" -lt 1 ] || [ "$#" -gt 2 ]; then
-    error "usage: $0 <path to main directory of an EESSI stack>"
+    error "usage: $0 <path to main directory of an EESSI stack> [<path to Lmod's update_lmod_system_cache_files script>]"
 fi
 
 stack_base_dir="$1"