1 files changed, 23 insertions, 0 deletions
diff --git a/lib/hooks/pre-commit b/lib/hooks/pre-commit
index e69de29..bcd164c 100755
--- a/lib/hooks/pre-commit
+++ b/lib/hooks/pre-commit
@@ -0,0 +1,23 @@
+#!/usr/bin/env sh
+
+# full paths from the repo root separated by newlines
+MUST_NOT_CHANGE='hardware-configuration.nix
+key2.json'
+
+if git rev-parse --verify HEAD >/dev/null 2>&1
+then
+  against=HEAD
+else
+  # Initial commit: diff against an empty tree object
+  against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
+fi
+
+exec 1>&2
+
+if git diff --cached --name-only $against | grep --quiet --line-regexp --fixed-strings "$MUST_NOT_CHANGE"
+then
+  echo Commit would modify one or more files that must not change.
+  exit 1
+else
+  exit 0
+fi
\ No newline at end of file