From 6739fca645cba0f93f7082310f39e380461774c7 Mon Sep 17 00:00:00 2001
From: Tim Wojtulewicz <tim@corelight.com>
Date: Fri, 30 Aug 2024 10:24:45 -0700
Subject: [PATCH] DNS_Mgr: Remove usage of ares_getsock from GetNextTimeout

---
 src/DNS_Mgr.cc | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/src/DNS_Mgr.cc b/src/DNS_Mgr.cc
index 4e17e5c26f..2cd157e443 100644
--- a/src/DNS_Mgr.cc
+++ b/src/DNS_Mgr.cc
@@ -1315,23 +1315,19 @@ double DNS_Mgr::GetNextTimeout() {
     if ( asyncs_pending == 0 )
         return -1;
 
-    int nfds = 0;
-    ares_socket_t socks[ARES_GETSOCK_MAXNUM];
-    int bitmap = ares_getsock(channel, socks, ARES_GETSOCK_MAXNUM);
-    for ( int i = 0; i < ARES_GETSOCK_MAXNUM; i++ ) {
-        if ( ARES_GETSOCK_READABLE(bitmap, i) || ARES_GETSOCK_WRITABLE(bitmap, i) )
-            ++nfds;
-    }
+    struct timeval tv;
+    struct timeval* tvp = ares_timeout(channel, NULL, &tv);
 
-    // Do we have any sockets that are read or writable?
-    if ( nfds == 0 )
+    // If you pass NULL as the max time argument to ares_timeout, it will return null if there
+    // isn't anything waiting to be processed.
+    if ( ! tvp )
         return -1;
 
-    struct timeval tv;
-    tv.tv_sec = DNS_TIMEOUT;
-    tv.tv_usec = 0;
-
-    struct timeval* tvp = ares_timeout(channel, &tv, &tv);
+    // Clamp the timeout to our desired max, since we passed NULl to ares_timeout.
+    if ( tvp->tv_sec > DNS_TIMEOUT ) {
+        tvp->tv_sec = DNS_TIMEOUT;
+        tvp->tv_usec = 0;
+    }
 
     return static_cast<double>(tvp->tv_sec) + (static_cast<double>(tvp->tv_usec) / 1e6);
 }