1 files changed, 17 insertions, 0 deletions
diff --git a/pkgs/build-support/setup-hooks/canonicalize-jars.sh b/pkgs/build-support/setup-hooks/canonicalize-jars.sh
new file mode 100644
index 0000000000000..8c55810748ea0
--- /dev/null
+++ b/pkgs/build-support/setup-hooks/canonicalize-jars.sh
@@ -0,0 +1,17 @@
+# This setup hook causes the fixup phase to repack all JAR files in a
+# canonical & deterministic fashion, e.g. resetting mtimes (like with normal
+# store files) and avoiding impure metadata.
+
+fixupOutputHooks+=('if [ -z "$dontCanonicalizeJars" -a -e "$prefix" ]; then canonicalizeJarsIn "$prefix"; fi')
+
+canonicalizeJarsIn() {
+  local dir="$1"
+  header "canonicalizing jars in $dir"
+  dir="$(realpath -sm -- "$dir")"
+  while IFS= read -rd '' f; do
+    canonicalizeJar "$f"
+  done < <(find -- "$dir" -type f -name '*.jar' -print0)
+  stopNest
+}
+
+source @canonicalize_jar@