From bffe386f2d5f71066c8e6be70e61c0195360730c Mon Sep 17 00:00:00 2001
From: Erik Boasson <eb@ilities.com>
Date: Sun, 14 Jun 2020 20:03:04 +0200
Subject: [PATCH] No extra transmit socket in MSM_NO_UNICAST mode

Reuse unicast data socket in MSM_NO_UNICAST, just like it did in all
modes before the extra socket was introduced in
d1ed8df9f343b1cd441e3cd7ceaa750b480b7ce9.  This restores support for the
"raw ethernet" transport on Linux by no longer requiring the transport
to create a socket with an arbitrary "port".

Signed-off-by: Erik Boasson <eb@ilities.com>
---
 src/core/ddsi/src/q_init.c | 43 +++++++++++++++++++-------------------
 1 file changed, 22 insertions(+), 21 deletions(-)

diff --git a/src/core/ddsi/src/q_init.c b/src/core/ddsi/src/q_init.c
index 29a2f00..7feebec 100644
--- a/src/core/ddsi/src/q_init.c
+++ b/src/core/ddsi/src/q_init.c
@@ -1010,6 +1010,22 @@ void ddsi_set_deafmute (struct ddsi_domaingv *gv, bool deaf, bool mute, int64_t
   GVLOGDISC ("\n");
 }
 
+static void free_conns (struct ddsi_domaingv *gv)
+{
+  // Depending on settings, various "conn"s can alias others, this makes sure we free each one only once
+  // FIXME: perhaps store them in a table instead?
+  ddsi_tran_conn_t cs[] = { gv->xmit_conn, gv->disc_conn_mc, gv->data_conn_mc, gv->disc_conn_uc, gv->data_conn_uc };
+  for (size_t i = 0; i < sizeof (cs) / sizeof (cs[0]); i++)
+  {
+    if (cs[i] == NULL)
+      continue;
+    for (size_t j = i + 1; j < sizeof (cs) / sizeof (cs[0]); j++)
+      if (cs[i] == cs[j])
+        cs[j] = NULL;
+    ddsi_conn_free (cs[i]);
+  }
+}
+
 int rtps_init (struct ddsi_domaingv *gv)
 {
   uint32_t port_disc_uc = 0;
@@ -1390,7 +1406,10 @@ int rtps_init (struct ddsi_domaingv *gv)
     }
   }
 
-  /* Create shared transmit connection */
+  /* Create shared transmit connection -- FIXME: no longer needed, but can't do the testing right now */
+  if (gv->config.many_sockets_mode == MSM_NO_UNICAST)
+    gv->xmit_conn = gv->data_conn_uc;
+  else
   {
     const ddsi_tran_qos_t qos = { .m_purpose = DDSI_TRAN_QOS_XMIT, .m_diffserv = 0 };
     dds_return_t rc;
@@ -1534,18 +1553,9 @@ err_post_omg_security_init:
 #endif
 #endif
 err_mc_conn:
-  if (gv->xmit_conn)
-    ddsi_conn_free (gv->xmit_conn);
-  if (gv->disc_conn_mc)
-    ddsi_conn_free (gv->disc_conn_mc);
-  if (gv->data_conn_mc && gv->data_conn_mc != gv->disc_conn_mc)
-    ddsi_conn_free (gv->data_conn_mc);
+  free_conns (gv);
   if (gv->pcap_fp)
     ddsrt_mutex_destroy (&gv->pcap_lock);
-  if (gv->disc_conn_uc != gv->disc_conn_mc)
-    ddsi_conn_free (gv->disc_conn_uc);
-  if (gv->data_conn_uc != gv->disc_conn_uc)
-    ddsi_conn_free (gv->data_conn_uc);
   free_group_membership (gv->mship);
 err_unicast_sockets:
   ddsi_tkmap_free (gv->m_tkmap);
@@ -1876,16 +1886,7 @@ void rtps_fini (struct ddsi_domaingv *gv)
   ddsrt_thread_pool_free (gv->thread_pool);
 
   (void) joinleave_spdp_defmcip (gv, 0);
-
-  ddsi_conn_free (gv->xmit_conn);
-  ddsi_conn_free (gv->disc_conn_mc);
-  if (gv->data_conn_mc != gv->disc_conn_mc)
-    ddsi_conn_free (gv->data_conn_mc);
-  if (gv->disc_conn_uc != gv->disc_conn_mc)
-    ddsi_conn_free (gv->disc_conn_uc);
-  if (gv->data_conn_uc != gv->disc_conn_uc)
-    ddsi_conn_free (gv->data_conn_uc);
-
+  free_conns (gv);
   free_group_membership(gv->mship);
   ddsi_tran_factories_fini (gv);