bootctl: create loader.conf only if it doesn't exist yet

If the snippet aleady exists, don't do anything, as the file was already
installed then.

(This also reworks the code to create the file atomically)

Fixes: #5396

diff --git a/src/basic/fs-util.h b/src/basic/fs-util.h
index 3f47537de147fb2b0689cc89f238f3596ccf7f16..60f465a4d919bf2a301bdd66c916c6994b732a29 100644 (file)
--- a/src/basic/fs-util.h
+++ b/src/basic/fs-util.h
@@ -104,3 +104,9 @@ static inline void rmdir_and_free(char *p) {
         free(p);
 }
 DEFINE_TRIVIAL_CLEANUP_FUNC(char*, rmdir_and_free);
+
+static inline void unlink_and_free(char *p) {
+        (void) unlink(p);
+        free(p);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(char*, unlink_and_free);