fix: partially fix a bug that prevented group part messages from

sending.

When a peer leaves a group, they send a packet to the group
indicating that they're leaving. However if this packet is sent
via TCP, it gets put in a packet queue, which is then destroyed
on the rest of the group cleanup process before ever being able
to send.

This pr allows do_gc() to finish an iteration before cleaning the
group up, which allows the TCP packet queue to be emptied. However
this bug still exists on a tox_kill() event because we don't have
a chance to do another do_gc() iteration.

Author: JFreegman

auto_tests/group_general_test.c

@@ -441,10 +441,13 @@ static void group_announce_test(AutoTox *autotoxes)
     tox_group_leave(tox1, groupnumber, nullptr, 0, &err_exit);
     ck_assert(err_exit == TOX_ERR_GROUP_LEAVE_OK);
 
-    num_groups1 = tox_group_get_number_groups(tox0);
-    num_groups2 = tox_group_get_number_groups(tox1);
+    while (num_groups1 != 0 || num_groups2 != 0) {
+        num_groups1 = tox_group_get_number_groups(tox0);
+        num_groups2 = tox_group_get_number_groups(tox1);
+
+        iterate_all_wait(autotoxes, NUM_GROUP_TOXES, ITERATION_INTERVAL);
+    }
 
-    ck_assert(num_groups1 == num_groups2 && num_groups2 == 0);
 
     printf("All tests passed!\n");
 }

other/bootstrap_daemon/docker/tox-bootstrapd.sha256

@@ -1 +1 @@
-7dfcf534fb80fbd8337337f5aa9eaa120febc72386046c7ab0d5c7545e900657  /usr/local/bin/tox-bootstrapd
+e5ccf844b7ece48d1153c226bdf8462d0e85d517dfcd720c8d6c4abad7da6929  /usr/local/bin/tox-bootstrapd

toxcore/group_chats.c

@@ -7281,6 +7281,10 @@ void do_gc(GC_Session *c, void *userdata)
 
         do_new_connection_cooldown(chat);
         do_peer_delete(c, chat, userdata);
+
+        if (chat->flag_exit) {  // should always come last as it modifies the chats array
+            group_delete(c, chat);
+        }
     }
 }
 
@@ -8270,14 +8274,21 @@ static void group_delete(GC_Session *c, GC_Chat *chat)
         c->chats_index = i;
 
         if (!realloc_groupchats(c, c->chats_index)) {
-            LOGGER_ERROR(chat->log, "Failed to reallocate groupchats array");
+            LOGGER_ERROR(c->messenger->log, "Failed to reallocate groupchats array");
         }
     }
 }
 
 int gc_group_exit(GC_Session *c, GC_Chat *chat, const uint8_t *message, uint16_t length)
 {
-    const int ret =  group_can_handle_packets(chat) ? send_gc_self_exit(chat, message, length) : 0;
+    chat->flag_exit = true;
+    return group_can_handle_packets(chat) ? send_gc_self_exit(chat, message, length) : 0;
+}
+
+non_null()
+static int kill_group(GC_Session *c, GC_Chat *chat)
+{
+    const int ret = gc_group_exit(c, chat, nullptr, 0);
     group_delete(c, chat);
     return ret;
 }
@@ -8295,11 +8306,9 @@ void kill_dht_groupchats(GC_Session *c)
             continue;
         }
 
-        if (group_can_handle_packets(chat)) {
-            send_gc_self_exit(chat, nullptr, 0);
+        if (kill_group(c, chat) != 0) {
+            LOGGER_WARNING(c->messenger->log, "Failed to send group exit packet");
         }
-
-        group_cleanup(c, chat);
     }
 
     networking_registerhandler(c->messenger->net, NET_PACKET_GC_LOSSY, nullptr, nullptr);

toxcore/group_common.h

@@ -321,6 +321,8 @@ typedef struct GC_Chat {
 
     uint8_t     m_group_public_key[CRYPTO_PUBLIC_KEY_SIZE];  // public key for group's messenger friend connection
     int         friend_connection_id;  // identifier for group's messenger friend connection
+
+    bool        flag_exit;  // true if the group will be deleted after the next do_gc() iteration
 } GC_Chat;
 
 #ifndef MESSENGER_DEFINED