From 573cd469abcdcffe16300c6a6d975e61ab94a0a7 Mon Sep 17 00:00:00 2001
From: david <david@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Tue, 6 Aug 2013 02:09:15 +0000
Subject: [PATCH] Allow do_listen to return an error.

---
 ncat/ncat_listen.c | 6 ++++++
 ncat/ncat_proxy.c  | 2 ++
 ncat/util.c        | 4 +++-
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/ncat/ncat_listen.c b/ncat/ncat_listen.c
index 1ece9cbf4..294da1b80 100644
--- a/ncat/ncat_listen.c
+++ b/ncat/ncat_listen.c
@@ -271,6 +271,8 @@ static int ncat_listen_stream(int proto)
     for (i = 0; i < num_listenaddrs; i++) {
         /* setup the main listening socket */
         listen_socket[i] = do_listen(SOCK_STREAM, proto, &listenaddrs[i]);
+        if (listen_socket[i] == -1)
+            bye("do_listen: %s", socket_strerror(socket_errno()));
 
         /* Make our listening socket non-blocking because there are timing issues
          * which could cause us to block on accept() even though select() says it's
@@ -659,6 +661,8 @@ static int ncat_listen_dgram(int proto)
     for (i = 0; i < num_listenaddrs; i++) {
         /* create the UDP listen sockets */
         sockfd[i] = do_listen(SOCK_DGRAM, proto, &listenaddrs[i]);
+        if (sockfd[i] == -1)
+            bye("do_listen: %s", socket_strerror(socket_errno()));
         FD_SET(sockfd[i], &listen_fds);
         add_fd(&listen_fdlist, sockfd[i]);
     }
@@ -676,6 +680,8 @@ static int ncat_listen_dgram(int proto)
 
             /* Rebuild the udp socket which got burnt */
             sockfd[fdn] = do_listen(SOCK_DGRAM, proto, &listenaddrs[fdn]);
+            if (sockfd[i] == -1)
+                bye("do_listen: %s", socket_strerror(socket_errno()));
             FD_SET(sockfd[fdn], &listen_fds);
             add_fd(&listen_fdlist, sockfd[fdn]);
 
diff --git a/ncat/ncat_proxy.c b/ncat/ncat_proxy.c
index 818f4082b..23ab8e211 100644
--- a/ncat/ncat_proxy.c
+++ b/ncat/ncat_proxy.c
@@ -218,6 +218,8 @@ int ncat_http_server(void)
     /* Listen on each address, set up lists for select */
     for (i = 0; i < num_listenaddrs; i++) {
         listen_socket[i] = do_listen(SOCK_STREAM, IPPROTO_TCP, &listenaddrs[i]);
+        if (listen_socket[i] == -1)
+            bye("do_listen: %s", socket_strerror(socket_errno()));
 
         /* make us not block on accepts in wierd cases. See ncat_listen.c:209 */
         unblock_socket(listen_socket[i]);
diff --git a/ncat/util.c b/ncat/util.c
index 4b97ca48c..b8317d22b 100644
--- a/ncat/util.c
+++ b/ncat/util.c
@@ -387,6 +387,8 @@ unsigned short inet_port(const union sockaddr_u *su)
     return 0;
 }
 
+/* Return a listening socket after setting various characteristics on it.
+   Returns -1 on error. */
 int do_listen(int type, int proto, const union sockaddr_u *srcaddr_u)
 {
     int sock = 0, option_on = 1;
@@ -400,7 +402,7 @@ int do_listen(int type, int proto, const union sockaddr_u *srcaddr_u)
        nbase. */
     sock = inheritable_socket(srcaddr_u->storage.ss_family, type, proto);
     if (sock < 0)
-      bye("socket: %s", socket_strerror(socket_errno()));
+        return -1;
 
     Setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &option_on, sizeof(int));