Add missing NULL check in arg_parse.c

Previous implementation didn't crash because `closedir(...)` is lenient.

diff --git a/src/arg_parse.c b/src/arg_parse.c
index 87a539eae3d308d1af1db3f602604c779d5693c5..f56b2cc38ec51d5c9d299c721efeaa065b23edd4 100644 (file)
--- a/src/arg_parse.c
+++ b/src/arg_parse.c
@@ -184,7 +184,9 @@ Args parse_args(int32_t argc, char **argv) {
       } else {
         printf("Directory \"%s\" exists.\n", args.generate_dir);
       }
-      closedir(d);
+      if (d) {
+        closedir(d);
+      }
     } else if (strcmp(argv[0], "--generate-enable-overwrite") == 0) {
       args.flags |= 4;
     } else {