From 1c24b7ab796e684131939ce034e07af0bd94f984 Mon Sep 17 00:00:00 2001
From: Thomas Roeblitz <thomas.roblitz@uib.no>
Date: Fri, 15 Nov 2024 10:27:33 +0100
Subject: [PATCH] clean up lower dir changes

---
 eessi_container.sh | 48 +++++++++++-----------------------------------
 1 file changed, 11 insertions(+), 37 deletions(-)

diff --git a/eessi_container.sh b/eessi_container.sh
index 069da99d14..73244778cf 100755
--- a/eessi_container.sh
+++ b/eessi_container.sh
@@ -756,21 +756,9 @@ do
             # to be able to see the contents of the read-write session we have to mount
             # the fuse-overlayfs (in read-only mode) on top of the CernVM-FS repository
 
-            echo "While processing '${cvmfs_repo_name}' to be mounted 'read-only'"
-            echo "   we detected one or more overlay-upper* directories"
-            echo "   (${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-upper*)"
-            echo "   likely originating from a previous session. Will use then as"
-            echo "   left-most directory in 'lowerdir' argument for fuse-overlayfs."
-
-            lowerdirs=/cvmfs_ro/${cvmfs_repo_name}
-            # # check if there are more overlay-upper directories, e.g., with three digit suffix
-            # for dir in $(ls ${EESSI_TMPDIR}/${cvmfs_repo_name} | grep -E "overlay-upper-[0-9]{3}" | cut -f3 -d- | sort -n); do
-            #     lowerdirs=${TMP_IN_CONTAINER}/${cvmfs_repo_name}/overlay-upper-${dir}:${lowerdirs}
-            # done
-            # finally add most recent overlay-upper to lowerdirs
-            lowerdirs=${TMP_IN_CONTAINER}/${cvmfs_repo_name}/overlay-upper:${lowerdirs}
-            [[ ${VERBOSE} -eq 1 ]] && ls ${EESSI_TMPDIR}/${cvmfs_repo_name}
-            [[ ${VERBOSE} -eq 1 ]] && echo ${lowerdirs}
+            echo "While processing '${cvmfs_repo_name}' to be mounted 'read-only' we detected an overlay-upper"
+            echo "  directory (${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-upper) likely from a previous"
+            echo "  session. Will use it as left-most directory in 'lowerdir' argument for fuse-overlayfs."
 
             # make the target CernVM-FS repository available under /cvmfs_ro
             export EESSI_READONLY="container:cvmfs2 ${cvmfs_repo_name} /cvmfs_ro/${cvmfs_repo_name}"
@@ -779,7 +767,12 @@ do
 
             # now, put the overlay-upper read-only on top of the repo and make it available under the usual prefix /cvmfs
             EESSI_READONLY_OVERLAY="container:fuse-overlayfs"
-            EESSI_READONLY_OVERLAY+=" -o lowerdir=${lowerdirs}"
+            # The contents of the previous session are available under
+            #   ${EESSI_TMPDIR} which is bind mounted to ${TMP_IN_CONTAINER}.
+            #   Hence, we have to use ${TMP_IN_CONTAINER}/${cvmfs_repo_name}/overlay-upper
+            # the left-most directory given for the lowerdir argument is put on top,
+            #   and with no upperdir=... the whole overlayfs is made available read-only
+            EESSI_READONLY_OVERLAY+=" -o lowerdir=${TMP_IN_CONTAINER}/${cvmfs_repo_name}/overlay-upper:/cvmfs_ro/${cvmfs_repo_name}"
             EESSI_READONLY_OVERLAY+=" /cvmfs/${cvmfs_repo_name}"
             export EESSI_READONLY_OVERLAY
 
@@ -795,27 +788,7 @@ do
             export EESSI_FUSE_MOUNTS
         fi
     elif [[ ${cvmfs_repo_access} == "rw" ]] ; then
-        # use repo-specific overlay directories; if there is already an
-        # overlay-upper (e.g., from a previous run) move it to overlay-upper-SEQ
-        # and create a new one; all overlay-upper-SEQs must be added to lowerdir
-        # starting with the lowest number first and preprending it to the lowerdir
-        # setting
-        lowerdirs=/cvmfs_ro/${cvmfs_repo_name}
-        # if [ -d ${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-upper ]; then
-        #     # determine next sequence number
-        #     last_seq_num=$(ls ${EESSI_TMPDIR}/${cvmfs_repo_name} | grep -E "overlay-upper-[0-9]{3}" | cut -f3 -d- | sort -n | tail -n 1 | sed -e 's/^0*//')
-        #     if [ -n ${last_seq_num} ]; then
-        #         last_seq_num=0
-        #     fi
-        #     next_seq_num=$(($last_seq_num + 1))
-        #     next_ovl_upper=$(printf "overlay-upper-%03d" ${next_seq_num})
-        #     mv ${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-upper ${EESSI_TMPDIR}/${cvmfs_repo_name}/${next_ovl_upper}
-        #     for dir in $(ls ${EESSI_TMPDIR}/${cvmfs_repo_name} | grep -E "overlay-upper-[0-9]{3}" | cut -f3 -d- | sort -n); do
-        #         lowerdirs=${TMP_IN_CONTAINER}/${cvmfs_repo_name}/overlay-upper-${dir}:${lowerdirs}
-        #     done
-        #     [[ ${VERBOSE} -eq 1 ]] && ls ${EESSI_TMPDIR}/${cvmfs_repo_name}
-        #     [[ ${VERBOSE} -eq 1 ]] && echo ${lowerdirs}
-        # fi
+        # use repo-specific overlay directories
         mkdir -p ${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-upper
         mkdir -p ${EESSI_TMPDIR}/${cvmfs_repo_name}/overlay-work
         [[ ${VERBOSE} -eq 1 ]] && echo -e "TMP directory contents:\n$(ls -l ${EESSI_TMPDIR})"
@@ -826,6 +799,7 @@ do
         EESSI_FUSE_MOUNTS+=("--fusemount" "${EESSI_READONLY}")
 
         EESSI_WRITABLE_OVERLAY="container:fuse-overlayfs"
+        lowerdirs=/cvmfs_ro/${cvmfs_repo_name}
         if [[ ! -z ${LOWER_DIRS} ]]; then
             # need to convert ':' in LOWER_DIRS to ',' because bind mounts use ',' as
             # separator while the lowerdir overlayfs option uses ':'