[PATCH v2 6/6] notes.c: make "struct string_list display_notes_refs" non-static

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

Change the "struct string_list" added in 894a9d333e9 (Support showing
notes from more than one notes tree, 2010-03-12) to be non-static. Now
we don't need to flip-flop from "NODUP" to ".strdup_strings = 1".

In 2721ce21e43 (use string_list initializer consistently, 2016-06-13)
the statically initialized variable was made to use
"STRING_LIST_INIT_NODUP". That was correct in the narrow sense, but
didn't make much sense when this code was viewed as a whole. We'd set
it to "NODUP" just to set it to "DUP" when we'd use it.

This change could be smaller in just changing the "NODUP" to a "DUP",
but let's prove to ourselves and the compiler that this data is only
ever used when we enter load_display_notes(). We can just allocate it
in that function, and pass it to the notes_display_config() callback.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 notes.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/notes.c b/notes.c
index acc35b580b6..272fcb270a1 100644
--- a/notes.c
+++ b/notes.c
@@ -75,7 +75,6 @@ struct non_note {
 
 struct notes_tree default_notes_tree;
 
-static struct string_list display_notes_refs = STRING_LIST_INIT_NODUP;
 static struct notes_tree **display_notes_trees;
 
 static void load_subtree(struct notes_tree *t, struct leaf_node *subtree,
@@ -967,14 +966,19 @@ void string_list_add_refs_from_colon_sep(struct string_list *list,
 	free(globs_copy);
 }
 
+struct notes_display_config_cb {
+	struct string_list *list;
+	int *load_refs;
+};
+
 static int notes_display_config(const char *k, const char *v, void *cb)
 {
-	int *load_refs = cb;
+	struct notes_display_config_cb *data = cb;
 
-	if (*load_refs && !strcmp(k, "notes.displayref")) {
+	if (*data->load_refs && !strcmp(k, "notes.displayref")) {
 		if (!v)
 			return config_error_nonbool(k);
-		string_list_add_refs_by_glob(&display_notes_refs, v);
+		string_list_add_refs_by_glob(data->list, v);
 	}
 
 	return 0;
@@ -1080,7 +1084,11 @@ void load_display_notes(struct display_notes_opt *opt)
 {
 	char *display_ref_env;
 	int load_config_refs = 0;
-	display_notes_refs.strdup_strings = 1;
+	struct string_list display_notes_refs = STRING_LIST_INIT_DUP;
+	struct notes_display_config_cb cb_data = {
+		.list = &display_notes_refs,
+		.load_refs = &load_config_refs,
+	};
 
 	assert(!display_notes_trees);
 
@@ -1096,7 +1104,7 @@ void load_display_notes(struct display_notes_opt *opt)
 			load_config_refs = 1;
 	}
 
-	git_config(notes_display_config, &load_config_refs);
+	git_config(notes_display_config, &cb_data);
 
 	if (opt) {
 		struct string_list_item *item;
-- 
2.37.1.1095.g64a1e8362fd