lib-storage: mail_add_temp_wanted_fields() - delay opening stream

Allows plugins to call it in mail.get_stream() without infinite loop.

diff --git a/src/lib-storage/index/index-mail.c b/src/lib-storage/index/index-mail.c
index 0b920691da504146270e57cdd3ae030a61f98f41..25525c95cf4e12587f3060a9c5334f75c2628c58 100644 (file)
--- a/src/lib-storage/index/index-mail.c
+++ b/src/lib-storage/index/index-mail.c
@@ -2009,7 +2009,16 @@ void index_mail_add_temp_wanted_fields(struct mail *_mail,
                data->wanted_headers = new_wanted_headers;
        }
        index_mail_update_access_parts_pre(_mail);
-       index_mail_update_access_parts_post(_mail);
+       /* Don't call _post(), which would try to open the stream. It should be
+          enough to delay the opening until it happens anyway.
+
+          Otherwise there's not really any good place to call this in the
+          plugins: set_seq() call get_stream() internally, which can already
+          start parsing the headers, so it's too late. If we use get_stream()
+          and there's a _post() call here, it gets into infinite loop. The
+          loop could probably be prevented in some way, but it's probably
+          better to eventually try to remove the _post() call entirely
+          everywhere. */
 }
 
 void index_mail_set_uid_cache_updates(struct mail *_mail, bool set)