From 9dec748e86c708c147de2f9975a56c1cc75e2807 Mon Sep 17 00:00:00 2001
From: Michael Ortmann <41313082+michaelortmann@users.noreply.github.com>
Date: Sun, 1 Oct 2023 17:01:40 +0200
Subject: [PATCH] Fix connection refused detection under Cygwin

Found by: michaelortmann
Patch by: michaelortmann
---
 src/dcc.c |  3 +++
 src/net.c | 15 +++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/dcc.c b/src/dcc.c
index 77cdb7e29..c4f478f37 100644
--- a/src/dcc.c
+++ b/src/dcc.c
@@ -1421,6 +1421,9 @@ static void dcc_telnet_hostresolved(int i)
   strcpy(dcc[j].nick, "*");
   dcc[j].u.ident_sock = dcc[i].sock;
   dcc[j].timeval = now;
+#ifdef CYGWIN_HACKS
+  threaddata()->socklist[findsock(dcc[j].sock)].flags = SOCK_CONNECT;
+#endif
   dprintf(j, "%d, %d\n", dcc[i].port, dcc[idx].port);
 }
 
diff --git a/src/net.c b/src/net.c
index 63458da44..b5dbd04e9 100644
--- a/src/net.c
+++ b/src/net.c
@@ -1410,6 +1410,21 @@ void dequeue_sockets()
   for (i = 0; i < threaddata()->MAXSOCKS; i++) {
     if (!(socklist[i].flags & (SOCK_UNUSED | SOCK_TCL)) &&
         (socklist[i].handler.sock.outbuf != NULL) && (FD_ISSET(socklist[i].sock, &wfds))) {
+#ifdef CYGWIN_HACKS
+      int res;
+      socklen_t res_len;
+      if (socklist[i].flags == SOCK_CONNECT) {
+        res_len = sizeof(res);
+        getsockopt(socklist[i].sock, SOL_SOCKET, SO_ERROR, &res, &res_len);
+        if (res == ECONNREFUSED) { /* Connection refused */
+          int idx = findanyidx(socklist[i].sock);
+          putlog(LOG_MISC, "*", "Connection refused: %s:%i", dcc[idx].host,
+                 dcc[idx].port);
+          socklist[i].flags |= SOCK_EOFD;
+          return ;
+        }
+      }
+#endif
       /* Trick tputs into doing the work */
       errno = 0;
 #ifdef TLS