Improve link creation

caches-manager

@@ -6,10 +6,38 @@ set -euo pipefail
 shopt -s nullglob
 
 create_cache() {
- echo "L: $2"
+ local dir
+ local parent
+ dir="$(realpath -s "$2")"
+ parent="$(dirname "${dir}")"
+ echo -n "Linking '${dir}'... "
  mkdir -p "$1"
- [ -e "$2" ] && rm -r "$2"
- ln -sT "$1" "$2" || true
+
+ if [ ! -d "${parent}" ]; then
+ echo "parent directory does not exist, skip."
+ return
+ fi
+
+ if [ ! -w "${parent}" ]; then
+ echo "no write access to parent directory, skip."
+ return
+ fi
+
+ if [ -L "${dir}" ]; then
+ if [ "$(readlink "${dir}")" == "$1" ]; then
+ echo "done."
+ return
+ fi
+ elif [ -e "${dir}" ]; then
+ echo -n "target exists, backing up... "
+ mv -fT "${dir}" "${dir}.bak"
+ fi
+
+ if ln -sfT "$1" "${dir}"; then
+ echo "done."
+ else
+ echo "failed."
+ fi
 }
 
 declare -a TARGETS