Fix errors on error paths found by oomer.

* Use-after-free because we free network before dht in one case.
* Various unchecked allocs in tests (not so important).
* We used to not check whether ping arrays were actually allocated in DHT.
* `ping_kill` and `ping_array_kill` used to crash when passing NULL.

Also:
* Added an assert in all public API functions to ensure tox isn't NULL.
  The error message you get from that is a bit nicer than "Segmentation
  fault" when clients (or our tests) do things wrong.
* Decreased the sleep time in iterate_all_wait from 20ms to 5ms.
  Everything seems to still work with 5ms, and this greatly decreases
  the amount of time spent per test run, making oomer run much faster.

1 files changed, 2 insertions, 2 deletions

diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index 6b691ad8..82c31147 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -1999,8 +1999,8 @@ Messenger *new_messenger(Mono_Time *mono_time, Messenger_Options *options, unsig
     m->net_crypto = new_net_crypto(m->log, m->mono_time, m->dht, &options->proxy_info);
 
     if (m->net_crypto == nullptr) {
-        kill_networking(m->net);
         kill_dht(m->dht);
+        kill_networking(m->net);
         friendreq_kill(m->fr);
         logger_kill(m->log);
         free(m);
@@ -2012,7 +2012,7 @@ Messenger *new_messenger(Mono_Time *mono_time, Messenger_Options *options, unsig
     m->onion_c =  new_onion_client(m->mono_time, m->net_crypto);
     m->fr_c = new_friend_connections(m->mono_time, m->onion_c, options->local_discovery_enabled);
 
-    if (!(m->onion && m->onion_a && m->onion_c)) {
+    if (!(m->onion && m->onion_a && m->onion_c && m->fr_c)) {
         kill_friend_connections(m->fr_c);
         kill_onion(m->onion);
         kill_onion_announce(m->onion_a);