Several bugfixes in dart:io's handing of sockets

dart/runtime/bin/eventhandler_macos.cc

Index: dart/runtime/bin/eventhandler_macos.cc
diff --git a/dart/runtime/bin/eventhandler_macos.cc b/dart/runtime/bin/eventhandler_macos.cc
index ede500f4028b0b64f88875ce0ad4c736ce260fc6..49ec2477e19b132b0033d078f664a68787d0c207 100644
--- a/dart/runtime/bin/eventhandler_macos.cc
+++ b/dart/runtime/bin/eventhandler_macos.cc
@@ -192,16 +192,13 @@ void EventHandlerImplementation::HandleInterruptFd() {
       shutdown_ = true;
     } else {
       SocketData* sd = GetSocketData(msg[i].id);
-      if ((msg[i].data & (1 << kShutdownReadCommand)) != 0) {
-        ASSERT(msg[i].data == (1 << kShutdownReadCommand));
+      if (IS_COMMAND(msg[i].data, kShutdownReadCommand)) {
         // Close the socket for reading.
         shutdown(sd->fd(), SHUT_RD);
-      } else if ((msg[i].data & (1 << kShutdownWriteCommand)) != 0) {
-        ASSERT(msg[i].data == (1 << kShutdownWriteCommand));
+      } else if (IS_COMMAND(msg[i].data, kShutdownWriteCommand)) {
         // Close the socket for writing.
         shutdown(sd->fd(), SHUT_WR);
-      } else if ((msg[i].data & (1 << kCloseCommand)) != 0) {
-        ASSERT(msg[i].data == (1 << kCloseCommand));
+      } else if (IS_COMMAND(msg[i].data, kCloseCommand)) {
         // Close the socket and free system resources.
         RemoveFromKqueue(kqueue_fd_, sd);
         intptr_t fd = sd->fd();
@@ -209,14 +206,15 @@ void EventHandlerImplementation::HandleInterruptFd() {
         socket_map_.Remove(GetHashmapKeyFromFd(fd), GetHashmapHashFromFd(fd));
         delete sd;
         DartUtils::PostInt32(msg[i].dart_port, 1 << kDestroyedEvent);
-      } else if ((msg[i].data & (1 << kReturnTokenCommand)) != 0) {
-        int count = msg[i].data & ((1 << kReturnTokenCommand) - 1);
+      } else if (IS_COMMAND(msg[i].data, kReturnTokenCommand)) {
+        int count = TOKEN_COUNT(msg[i].data);
         for (int i = 0; i < count; i++) {
           if (sd->ReturnToken()) {
             AddToKqueue(kqueue_fd_, sd);
           }
         }
       } else {
+        ASSERT_NO_COMMAND(msg[i].data);
         // Setup events to wait for.
         ASSERT((msg[i].data > 0) && (msg[i].data < kIntptrMax));
         ASSERT(sd->port() == 0);