Major rework of vm service events.

runtime/vm/message_handler.cc

 // Copyright (c) 2011, 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.
 
 #include "vm/message_handler.h"
 
 #include "vm/dart.h"
 #include "vm/lockers.h"
 #include "vm/port.h"
 
@@ skipping 20 matching lines @@
 };
 
 
 MessageHandler::MessageHandler()
     : queue_(new MessageQueue()),
       oob_queue_(new MessageQueue()),
       live_ports_(0),
       paused_(0),
       pause_on_start_(false),
       pause_on_exit_(false),
+      paused_on_start_(false),
       paused_on_exit_(false),
       pool_(NULL),
       task_(NULL),
       start_callback_(NULL),
       end_callback_(NULL),
       callback_data_(0) {
   ASSERT(queue_ != NULL);
   ASSERT(oob_queue_ != NULL);
 }
 
@@ skipping 167 matching lines @@
 void MessageHandler::TaskCallback() {
   ASSERT(Isolate::Current() == NULL);
   bool ok = true;
   bool run_end_callback = false;
   {
     MonitorLocker ml(&monitor_);
     // Initialize the message handler by running its start function,
     // if we have one.  For an isolate, this will run the isolate's
     // main() function.
     if (pause_on_start()) {
+      if (!paused_on_start_) {
+        NotifyPauseOnStart();
+        paused_on_start_ = true;
+      }
       HandleMessages(false, false);
       if (pause_on_start()) {
         // Still paused.
         task_ = NULL;  // No task in queue.
         return;
+      } else {
+        paused_on_start_ = false;
       }
     }
 
     if (start_callback_) {
       // Release the monitor_ temporarily while we call the start callback.
       // The monitor was acquired with the MonitorLocker above.
       monitor_.Exit();
       ok = start_callback_(callback_data_);
       ASSERT(Isolate::Current() == NULL);
       start_callback_ = NULL;
       monitor_.Enter();
     }
 
     // Handle any pending messages for this message handler.
     if (ok) {
       ok = HandleMessages(true, true);
     }
     task_ = NULL;  // No task in queue.
 
     if (!ok || !HasLivePorts()) {
       if (pause_on_exit()) {
-        if (FLAG_trace_service_pause_events && !paused_on_exit_) {
-          OS::PrintErr("Isolate %s paused before exiting. "
+        if (!paused_on_exit_) {
+          if (FLAG_trace_service_pause_events) {
+            OS::PrintErr("Isolate %s paused before exiting. "
                        "Use the Observatory to release it.\n", name());
+          }
+          NotifyPauseOnExit();
+          paused_on_exit_ = true;
         }
-        paused_on_exit_ = true;
       } else {
         if (FLAG_trace_isolates) {
         OS::Print("[-] Stopping message handler (%s):\n"
                   "\thandler:    %s\n",
                   (ok ? "no live ports" : "error"),
                   name());
         }
         pool_ = NULL;
         run_end_callback = true;
         paused_on_exit_ = false;
@@ skipping 42 matching lines @@
 
 void MessageHandler::decrement_live_ports() {
   MonitorLocker ml(&monitor_);
 #if defined(DEBUG)
   CheckAccess();
 #endif
   live_ports_--;
 }
 
 }  // namespace dart