VM restart + shutdown fixes

runtime/vm/debugger.cc

 // 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.
 
 #include "vm/debugger.h"
 
 #include "include/dart_api.h"
 
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
@@ skipping 292 matching lines @@
 
   if (FLAG_steal_breakpoints && event->IsPauseEvent()) {
     // We allow the embedder's default breakpoint handler to be overridden.
     isolate_->PauseEventHandler();
   } else if (event_handler_ != NULL) {
     (*event_handler_)(event);
   }
 
   if (ServiceNeedsDebuggerEvent(event->type()) && event->IsPauseEvent()) {
     // If we were paused, notify the service that we have resumed.
-    ServiceEvent service_event(event->isolate(), ServiceEvent::kResume);
-    service_event.set_top_frame(event->top_frame());
-    Service::HandleEvent(&service_event);
+    const Error& error =
+        Error::Handle(isolate_, isolate_->object_store()->sticky_error());
+    ASSERT(error.IsNull() || error.IsUnwindError());
+
+    // Only send a resume event when the isolate is not unwinding.
+    if (!error.IsUnwindError()) {
+      ServiceEvent service_event(event->isolate(), ServiceEvent::kResume);
+      service_event.set_top_frame(event->top_frame());
+      Service::HandleEvent(&service_event);
+    }
   }
 }
 
 
 void Debugger::SignalIsolateEvent(DebuggerEvent::EventType type) {
   if (HasEventHandler()) {
     DebuggerEvent event(isolate_, type);
     ASSERT(event.isolate_id() != ILLEGAL_ISOLATE_ID);
     if (type == DebuggerEvent::kIsolateInterrupted) {
       DebuggerStackTrace* trace = CollectStackTrace();
@@ skipping 17 matching lines @@
   if (HasEventHandler()) {
     SignalIsolateEvent(DebuggerEvent::kIsolateInterrupted);
   }
   Dart_IsolateInterruptCallback callback = isolate_->InterruptCallback();
   if (callback != NULL) {
     if (!(*callback)()) {
       if (FLAG_trace_isolates) {
         OS::Print("[!] Embedder api: terminating isolate:\n"
                   "\tisolate:    %s\n", isolate_->name());
       }
-      // TODO(turnidge): We should give the message handler a way to
-      // detect when an isolate is unwinding.
-      isolate_->message_handler()->set_pause_on_exit(false);
       const String& msg =
           String::Handle(String::New("isolate terminated by embedder"));
       return UnwindError::New(msg);
     }
   }
 
   // If any error occurred while in the debug message loop, return it here.
   const Error& error =
       Error::Handle(isolate_, isolate_->object_store()->sticky_error());
+  ASSERT(error.IsNull() || error.IsUnwindError());
   isolate_->object_store()->clear_sticky_error();
   return error.raw();
 }
 
 
 // The vm service handles breakpoint notifications in a different way
 // than the regular debugger breakpoint notifications.
 static void SendServiceBreakpointEvent(ServiceEvent::EventKind kind,
                                        Breakpoint* bpt) {
   if (Service::debug_stream.enabled()) {
@@ skipping 2846 matching lines @@
 }
 
 
 void Debugger::RegisterCodeBreakpoint(CodeBreakpoint* bpt) {
   ASSERT(bpt->next() == NULL);
   bpt->set_next(code_breakpoints_);
   code_breakpoints_ = bpt;
 }
 
 }  // namespace dart