reduce thread-unsafe use of static variables

- rework ip_ntoa() to avoid use of static variables
- rework sort_client_list() to avoid use of static variables
- move static 'lastdump' into Messenger struct
- rework ID2String() to avoid use of static variables; rename to id_to_string()
- fetch_broadcast_info(): attempt to mitigate risks from concurrent execution
- current_time_monotonic(): attempt to mitigate risks from concurrent execution
- comment on non-thread-safety of unix_time_update

1 files changed, 2 insertions, 0 deletions

diff --git a/toxcore/Messenger.h b/toxcore/Messenger.h
index 218ec18b..e1dba698 100644
--- a/toxcore/Messenger.h
+++ b/toxcore/Messenger.h
@@ -240,6 +240,8 @@ struct Messenger {
     Friend *friendlist;
     uint32_t numfriends;
 
+    time_t lastdump;
+
     uint8_t has_added_relays; // If the first connection has occurred in do_messenger
     Node_format loaded_relays[NUM_SAVED_TCP_RELAYS]; // Relays loaded from config