Add pause/resume for isolates in vmservice/observatory.

runtime/bin/dbg_connection.h

 // Copyright (c) 2012, 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_DBG_CONNECTION_H_
 #define BIN_DBG_CONNECTION_H_
 
 #include "bin/builtin.h"
 #include "bin/utils.h"
 
@@ skipping 33 matching lines @@
   int debug_fd() const { return debug_fd_; }
 
   // Return message id of current debug command message.
   int MessageId();
 
   // Starts the native thread which listens for connections from
   // debugger clients, reads and dispatches debug command messages
   // from the client.
   static int StartHandler(const char* address, int port_number);
 
+  // Initializes the parts of the debugger which are needed by the vm
+  // service.  This function should only be called when StartHandler
+  // is not called.
+  static void InitForVmService();
+
   // Called by Isolates when they need to wait for a connection
   // from debugger clients.
   static void WaitForConnection();
 
   // Sends a reply or an error message to a specific debugger client.
   static void SendMsg(int debug_fd, dart::TextBuffer* msg);
   static void SendError(int debug_fd, int msg_id, const char* err_msg);
 
   // Sends an event message to all debugger clients that are connected.
   static void BroadcastMsg(dart::TextBuffer* msg);
@@ skipping 28 matching lines @@
   static bool IsConnected();
 
   // Helper method for sending messages back to a debugger client.
   static void SendMsgHelper(int debug_fd, dart::TextBuffer* msg);
 
   // mutex/condition variable used by isolates when writing back to the
   // debugger. This is also used to ensure that the isolate waits for
   // a debugger to be attached when that is requested on the command line.
   static dart::Monitor* handler_lock_;
 
+  static bool IsListening() {
+    return listener_fd_ != -1;
+  }
+
   // The socket that is listening for incoming debugger connections.
   // This descriptor is created and closed by a native thread.
   static int listener_fd_;
 
   friend class DebuggerConnectionImpl;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(DebuggerConnectionHandler);
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // BIN_DBG_CONNECTION_H_