Fix broken Mac OS socket code

runtime/bin/socket.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef BIN_SOCKET_H_
 #define BIN_SOCKET_H_
 
 #include "bin/builtin.h"
 #include "bin/utils.h"
 
 #include "platform/globals.h"
 #include "platform/thread.h"
 // Declare the OS-specific types ahead of defining the generic class.
 #if defined(TARGET_OS_ANDROID)
 #include "bin/socket_android.h"
 #elif defined(TARGET_OS_LINUX)
 #include "bin/socket_linux.h"
 #elif defined(TARGET_OS_MACOS)
 #include "bin/socket_macos.h"
 #elif defined(TARGET_OS_WINDOWS)
 #include "bin/socket_win.h"
 #else
 #error Unknown target os.
 #endif
 
 
 union RawAddr {
-  // ss_family is always at ofset 0, thus we can add it here.
-  uint16_t ss_family;
   struct sockaddr_in in;
   struct sockaddr_in6 in6;
+  struct sockaddr_storage ss;
   struct sockaddr addr;
 };
 
 class SocketAddress {
  public:
   enum {
     TYPE_ANY = -1,
     TYPE_IPV4,
     TYPE_IPV6,
   };
 
   explicit SocketAddress(struct addrinfo* addrinfo);
 
   int GetType() {
-    if (addr_.ss_family == AF_INET6) return TYPE_IPV6;
+    if (addr_.ss.ss_family == AF_INET6) return TYPE_IPV6;
     return TYPE_IPV4;
   }
 
   const char* as_string() const { return as_string_; }
   const RawAddr& addr() const { return addr_; }
 
   static intptr_t GetAddrLength(const RawAddr& addr) {
-    return addr.ss_family == AF_INET6 ?
+    return addr.ss.ss_family == AF_INET6 ?
         sizeof(struct sockaddr_in6) : sizeof(struct sockaddr_in);
   }
 
   static int16_t FromType(int type) {
     if (type == TYPE_ANY) return AF_UNSPEC;
     if (type == TYPE_IPV4) return AF_INET;
     ASSERT(type == TYPE_IPV6 && "Invalid type");
     return AF_INET6;
   }
 
   static void SetAddrPort(RawAddr* addr, intptr_t port) {
-    if (addr->ss_family == AF_INET) {
+    if (addr->ss.ss_family == AF_INET) {
       addr->in.sin_port = htons(port);
     } else {
       addr->in6.sin6_port = htons(port);
     }
   }
 
   static intptr_t GetAddrPort(RawAddr* addr) {
-    if (addr->ss_family == AF_INET) {
+    if (addr->ss.ss_family == AF_INET) {
       return ntohs(addr->in.sin_port);
     } else {
       return ntohs(addr->in6.sin6_port);
     }
   }
 
  private:
   char as_string_[INET6_ADDRSTRLEN];
   RawAddr addr_;
 
@@ skipping 80 matching lines @@
   //   -5: invalid bindAddress
   static intptr_t CreateBindListen(RawAddr addr,
                                    intptr_t port,
                                    intptr_t backlog);
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(ServerSocket);
 };
 
 #endif  // BIN_SOCKET_H_