[Project] Rdns: Do not treat TCP channels failure as fatal

diff --git a/contrib/librdns/resolver.c b/contrib/librdns/resolver.c
index 6ef6d4558dd2c442b430452ec8909982600f3721..05d8383174b5d712afd469886a1970f99e3544f2 100644 (file)
--- a/contrib/librdns/resolver.c
+++ b/contrib/librdns/resolver.c
@@ -935,28 +935,46 @@ rdns_resolver_init (struct rdns_resolver *resolver)
        /* Now init io channels to all servers */
        UPSTREAM_FOREACH (resolver->servers, serv) {
                serv->io_channels = calloc (serv->io_cnt, sizeof (struct rdns_io_channel *));
+
+               if (serv->io_channels == NULL) {
+                       rdns_err ("cannot allocate memory for the resolver IO channels");
+                       return false;
+               }
+
                for (i = 0; i < serv->io_cnt; i ++) {
                        ioc = rdns_ioc_new(serv, resolver, false);
 
                        if (ioc == NULL) {
-                               rdns_err ("cannot allocate memory for the resolver IO channels");
+                               rdns_err ("cannot allocate memory or init the IO channel");
                                return false;
                        }
 
                        serv->io_channels[i] = ioc;
                }
 
+               int ntcp_channels = 0;
+
+               /*
+                * We are more forgiving for TCP IO channels: we can have zero of them
+                * if DNS is misconfigured and still be able to resolve stuff
+                */
                serv->tcp_io_channels = calloc (serv->tcp_io_cnt, sizeof (struct rdns_io_channel *));
+               if (serv->tcp_io_channels == NULL) {
+                       rdns_err ("cannot allocate memory for the resolver TCP IO channels");
+                       return false;
+               }
                for (i = 0; i < serv->tcp_io_cnt; i ++) {
                        ioc = rdns_ioc_new (serv, resolver, true);
 
                        if (ioc == NULL) {
-                               rdns_err ("cannot allocate memory for the resolver IO channels");
-                               return false;
+                               rdns_err ("cannot allocate memory or init the TCP IO channel");
+                               continue;
                        }
 
-                       serv->tcp_io_channels[i] = ioc;
+                       serv->tcp_io_channels[ntcp_channels++] = ioc;
                }
+
+               serv->tcp_io_cnt = ntcp_channels;
        }
 
        if (resolver->async->add_periodic) {