1 files changed, 34 insertions, 5 deletions

diff --git a/Utilities/cmlibuv/src/unix/udp.c b/Utilities/cmlibuv/src/unix/udp.c
index 7d699a1..71bfbf7 100644
--- a/Utilities/cmlibuv/src/unix/udp.c
+++ b/Utilities/cmlibuv/src/unix/udp.c
@@ -32,8 +32,6 @@
 #endif
 #include <sys/un.h>
 
-#define UV__UDP_DGRAM_MAXSIZE (64 * 1024)
-
 #if defined(IPV6_JOIN_GROUP) && !defined(IPV6_ADD_MEMBERSHIP)
 # define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
 #endif
@@ -377,8 +375,11 @@ write_queue_drain:
     return;
   }
 
+  /* Safety: npkts known to be >0 below. Hence cast from ssize_t
+   * to size_t safe.
+   */
   for (i = 0, q = QUEUE_HEAD(&handle->write_queue);
-       i < pkts && q != &handle->write_queue;
+       i < (size_t)npkts && q != &handle->write_queue;
        ++i, q = QUEUE_HEAD(&handle->write_queue)) {
     assert(q != NULL);
     req = QUEUE_DATA(q, uv_udp_send_t, queue);
@@ -504,6 +505,28 @@ static int uv__set_reuse(int fd) {
   return 0;
 }
 
+/*
+ * The Linux kernel suppresses some ICMP error messages by default for UDP
+ * sockets. Setting IP_RECVERR/IPV6_RECVERR on the socket enables full ICMP
+ * error reporting, hopefully resulting in faster failover to working name
+ * servers.
+ */
+static int uv__set_recverr(int fd, sa_family_t ss_family) {
+#if defined(__linux__)
+  int yes;
+
+  yes = 1;
+  if (ss_family == AF_INET) {
+    if (setsockopt(fd, IPPROTO_IP, IP_RECVERR, &yes, sizeof(yes)))
+      return UV__ERR(errno);
+  } else if (ss_family == AF_INET6) {
+    if (setsockopt(fd, IPPROTO_IPV6, IPV6_RECVERR, &yes, sizeof(yes)))
+       return UV__ERR(errno);
+  }
+#endif
+  return 0;
+}
+
 
 int uv__udp_bind(uv_udp_t* handle,
                  const struct sockaddr* addr,
@@ -514,7 +537,7 @@ int uv__udp_bind(uv_udp_t* handle,
   int fd;
 
   /* Check for bad flags. */
-  if (flags & ~(UV_UDP_IPV6ONLY | UV_UDP_REUSEADDR))
+  if (flags & ~(UV_UDP_IPV6ONLY | UV_UDP_REUSEADDR | UV_UDP_LINUX_RECVERR))
     return UV_EINVAL;
 
   /* Cannot set IPv6-only mode on non-IPv6 socket. */
@@ -530,6 +553,12 @@ int uv__udp_bind(uv_udp_t* handle,
     handle->io_watcher.fd = fd;
   }
 
+  if (flags & UV_UDP_LINUX_RECVERR) {
+    err = uv__set_recverr(fd, addr->sa_family);
+    if (err)
+      return err;
+  }
+
   if (flags & UV_UDP_REUSEADDR) {
     err = uv__set_reuse(fd);
     if (err)
@@ -854,7 +883,7 @@ static int uv__udp_set_membership6(uv_udp_t* handle,
 #if !defined(__OpenBSD__) &&                                        \
     !defined(__NetBSD__) &&                                         \
     !defined(__ANDROID__) &&                                        \
-    !defined(__DragonFly__) &                                       \
+    !defined(__DragonFly__) &&                                      \
     !defined(__QNX__)
 static int uv__udp_set_source_membership4(uv_udp_t* handle,
                                           const struct sockaddr_in* multicast_addr,