Restore synchronous name resolution (revert SVN rev52115).

These gethostbyaddr() calls should be changed to getaddrinfo() but only in
master.

Change-Id: I7e2d31ceb0e072beb7f324336d7b145c3adbe3a0
Reviewed-on: https://code.wireshark.org/review/7402
Reviewed-by: Jeff Morriss <jeff.morriss.ws@gmail.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/epan/addr_resolv.c b/epan/addr_resolv.c
index 5795fb06c9..6776001e31 100644
--- a/epan/addr_resolv.c
+++ b/epan/addr_resolv.c
@@ -857,6 +857,7 @@ static hashipv4_t *
 host_lookup(const guint addr, gboolean *found)
 {
     hashipv4_t * volatile tp;
+    struct hostent *hostp;
 
     *found = TRUE;
 
@@ -891,6 +892,25 @@ try_resolv:
         }
 #endif /* ASYNC_DNS */
 
+        /*
+         * The Windows "gethostbyaddr()" insists on translating 0.0.0.0 to
+         * the name of the host on which it's running; to work around that
+         * botch, we don't try to translate an all-zero IP address to a host
+         * name.
+         */
+        if (addr != 0) {
+            /* Use async DNS if possible, else fall back to timeouts,
+             * else call gethostbyaddr and hope for the best
+             */
+
+            hostp = gethostbyaddr((const char *)&addr, 4, AF_INET);
+
+            if (hostp != NULL && hostp->h_name[0] != '\0') {
+                g_strlcpy(tp->name, hostp->h_name, MAXNAMELEN);
+                return tp;
+            }
+        }
+
         /* unknown host or DNS timeout */
 
     }
@@ -922,6 +942,7 @@ host_lookup6(const struct e_in6_addr *addr, gboolean *found)
 #ifdef HAVE_C_ARES
     async_dns_queue_msg_t *caqm;
 #endif /* HAVE_C_ARES */
+    struct hostent *hostp;
 #endif /* INET6 */
 
     *found = TRUE;
@@ -971,6 +992,13 @@ try_resolv:
         }
 #endif /* HAVE_C_ARES */
 
+        /* Quick hack to avoid DNS/YP timeout */
+        hostp = gethostbyaddr((const char *)addr, sizeof(*addr), AF_INET6);
+
+        if (hostp != NULL && hostp->h_name[0] != '\0') {
+            g_strlcpy(tp->name, hostp->h_name, MAXNAMELEN);
+            return tp;
+        }
 #endif /* INET6 */
     }