win: make uv_udp_init_ex() accept UV_UDP_RECVMMSG

Commit 5736658b ("udp: add flag to enable recvmmsg(2) explicitly") added
the flag but didn't update the validation logic in src/win/udp.c.

This commit moves the validation logic to src/uv-common.c. The flag is
now accepted as a no-op on Windows.

Fixes: https://github.com/libuv/libuv/issues/2806
PR-URL: https://github.com/libuv/libuv/pull/2809
Reviewed-By: Bartosz Sosnowski <bartosz@janeasystems.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>

src/unix/udp.c

@@ -944,22 +944,13 @@ static int uv__udp_set_source_membership6(uv_udp_t* handle,
 #endif
 
 
-int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned int flags) {
+int uv__udp_init_ex(uv_loop_t* loop,
-  int domain;
+                    uv_udp_t* handle,
+                    unsigned flags,
+                    int domain) {
   int err;
-  int extra_flags;
   int fd;
 
-  /* Use the lower 8 bits for the domain */
-  domain = flags & 0xFF;
-  if (domain != AF_INET && domain != AF_INET6 && domain != AF_UNSPEC)
-    return UV_EINVAL;
-
-  /* Use the higher bits for extra flags */
-  extra_flags = flags & ~0xFF;
-  if (extra_flags & ~UV_UDP_RECVMMSG)
-    return UV_EINVAL;
-
   if (domain != AF_UNSPEC) {
     err = uv__socket(domain, SOCK_DGRAM, 0);
     if (err < 0)
@@ -978,18 +969,10 @@ int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned int flags) {
   QUEUE_INIT(&handle->write_queue);
   QUEUE_INIT(&handle->write_completed_queue);
 
-  if (extra_flags & UV_UDP_RECVMMSG)
-    handle->flags |= UV_HANDLE_UDP_RECVMMSG;
-
   return 0;
 }
 
 
-int uv_udp_init(uv_loop_t* loop, uv_udp_t* handle) {
-  return uv_udp_init_ex(loop, handle, AF_UNSPEC);
-}
-
-
 int uv_udp_open(uv_udp_t* handle, uv_os_sock_t sock) {
   int err;
 

src/uv-common.c

@@ -293,6 +293,36 @@ int uv_tcp_bind(uv_tcp_t* handle,
 }
 
 
+int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned flags) {
+  unsigned extra_flags;
+  int domain;
+  int rc;
+
+  /* Use the lower 8 bits for the domain. */
+  domain = flags & 0xFF;
+  if (domain != AF_INET && domain != AF_INET6 && domain != AF_UNSPEC)
+    return UV_EINVAL;
+
+  /* Use the higher bits for extra flags. */
+  extra_flags = flags & ~0xFF;
+  if (extra_flags & ~UV_UDP_RECVMMSG)
+    return UV_EINVAL;
+
+  rc = uv__udp_init_ex(loop, handle, flags, domain);
+
+  if (rc == 0)
+    if (extra_flags & UV_UDP_RECVMMSG)
+      handle->flags |= UV_HANDLE_UDP_RECVMMSG;
+
+  return rc;
+}
+
+
+int uv_udp_init(uv_loop_t* loop, uv_udp_t* handle) {
+  return uv_udp_init_ex(loop, handle, AF_UNSPEC);
+}
+
+
 int uv_udp_bind(uv_udp_t* handle,
                 const struct sockaddr* addr,
                 unsigned int flags) {

src/uv-common.h

@@ -139,6 +139,11 @@ int uv__tcp_connect(uv_connect_t* req,
                    unsigned int addrlen,
                    uv_connect_cb cb);
 
+int uv__udp_init_ex(uv_loop_t* loop,
+                    uv_udp_t* handle,
+                    unsigned flags,
+                    int domain);
+
 int uv__udp_bind(uv_udp_t* handle,
                  const struct sockaddr* addr,
                  unsigned int  addrlen,

src/win/udp.c

@@ -125,17 +125,10 @@ static int uv_udp_set_socket(uv_loop_t* loop, uv_udp_t* handle, SOCKET socket,
 }
 
 
-int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned int flags) {
+int uv__udp_init_ex(uv_loop_t* loop,
-  int domain;
+                    uv_udp_t* handle,
-
+                    unsigned flags,
-  /* Use the lower 8 bits for the domain */
+                    int domain) {
-  domain = flags & 0xFF;
-  if (domain != AF_INET && domain != AF_INET6 && domain != AF_UNSPEC)
-    return UV_EINVAL;
-
-  if (flags & ~0xFF)
-    return UV_EINVAL;
-
   uv__handle_init(loop, (uv_handle_t*) handle, UV_UDP);
   handle->socket = INVALID_SOCKET;
   handle->reqs_pending = 0;
@@ -174,11 +167,6 @@ int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned int flags) {
 }
 
 
-int uv_udp_init(uv_loop_t* loop, uv_udp_t* handle) {
-  return uv_udp_init_ex(loop, handle, AF_UNSPEC);
-}
-
-
 void uv_udp_close(uv_loop_t* loop, uv_udp_t* handle) {
   uv_udp_recv_stop(handle);
   closesocket(handle->socket);

test/test-udp-options.c

@@ -133,7 +133,7 @@ TEST_IMPL(udp_no_autobind) {
   uv_close((uv_handle_t*) &h, NULL);
 
   /* Test a non-lazily initialized socket. */
-  ASSERT(0 == uv_udp_init_ex(loop, &h2, AF_INET));
+  ASSERT(0 == uv_udp_init_ex(loop, &h2, AF_INET | UV_UDP_RECVMMSG));
   ASSERT(0 == uv_udp_set_multicast_ttl(&h2, 32));
   ASSERT(0 == uv_udp_set_broadcast(&h2, 1));