fetch-pack: don't needlessly copy fsck_options

Change the behavior of the .gitmodules validation added in
5476e1e (fetch-pack: print and use dangling .gitmodules,
2021-02-22) so we're using one "fsck_options".

I found that code confusing to read. One might think that not setting
up the error_func earlier means that we're relying on the "error_func"
not being set in some code in between the two hunks being modified
here.

But we're not, all we're doing in the rest of "cmd_index_pack()" is
further setup by calling fsck_set_msg_types(), and assigning to
do_fsck_object.

So there was no reason in 5476e1e to make a shallow copy of the
fsck_options struct before setting error_func. Let's just do this
setup at the top of the function, along with the "walk" assignment.

Signed-off-by: Ævar Arnfjörð Bjarmason <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: avar

builtin/index-pack.c

@@ -1761,6 +1761,7 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 
 	read_replace_refs = 0;
 	fsck_options.walk = mark_link;
+	fsck_options.error_func = print_dangling_gitmodules;
 
 	reset_pack_idx_option(&opts);
 	git_config(git_index_pack_config, &opts);
@@ -1951,13 +1952,8 @@ int cmd_index_pack(int argc, const char **argv, const char *prefix)
 	else
 		close(input_fd);
 
-	if (do_fsck_object) {
-		struct fsck_options fo = fsck_options;
-
-		fo.error_func = print_dangling_gitmodules;
-		if (fsck_finish(&fo))
-			die(_("fsck error in pack objects"));
-	}
+	if (do_fsck_object && fsck_finish(&fsck_options))
+		die(_("fsck error in pack objects"));
 
 	free(objects);
 	strbuf_release(&index_name_buf);