Give isolates names to be used during debugging.

runtime/lib/isolate.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 "platform/assert.h"
 #include "vm/bootstrap_natives.h"
 #include "vm/class_finalizer.h"
 #include "vm/dart.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_entry.h"
@@ skipping 230 matching lines @@
     const String& error_str = String::Handle(
         String::New("Error starting Isolate, class not loaded : "));
     const Error& error = Error::Handle(LanguageError::New(error_str));
     Isolate::Current()->object_store()->set_sticky_error(error);
     return false;
   }
   return true;  // No errors.
 }
 
 
+static char* BuildIsolateName(const char* script_name,
+                              const char* class_name,
+                              const char* func_name) {
+  // Skip past any slashes in the script name.
+  const char* last_slash = strrchr(script_name, '/');
+  if (last_slash != NULL) {
+    script_name = last_slash + 1;
+  }
+
+  const char* kFormat = "%s/%s.%s";
+  intptr_t len = OS::SNPrint(NULL, 0, kFormat, script_name, class_name,
+                             func_name) + 1;
+  char* chars = reinterpret_cast<char*>(
+      Isolate::Current()->current_zone()->Allocate(len));
+  OS::SNPrint(chars, len, kFormat, script_name, class_name, func_name);
+  return chars;
+}
+
+
 DEFINE_NATIVE_ENTRY(IsolateNatives_start, 2) {
   Isolate* preserved_isolate = Isolate::Current();
   const Instance& runnable = Instance::CheckedHandle(arguments->At(0));
   const Class& runnable_class = Class::Handle(runnable.clazz());
   const char* class_name = String::Handle(runnable_class.Name()).ToCString();
   const Library& library = Library::Handle(runnable_class.library());
   ASSERT(!library.IsNull());
   const char* library_url = String::Handle(library.url()).ToCString();
   intptr_t port_id = 0;
   LongJump jump;
   bool init_successful = true;
   Isolate* spawned_isolate = NULL;
   void* callback_data = preserved_isolate->init_callback_data();
   char* error = NULL;
   Dart_IsolateCreateCallback callback = Isolate::CreateCallback();
+  const char* isolate_name = BuildIsolateName(library_url, class_name, "main");
   if (callback == NULL) {
     error = strdup("Null callback specified for isolate creation\n");
-  } else if (callback(callback_data, &error)) {
+  } else if (callback(isolate_name, callback_data, &error)) {
     spawned_isolate = Isolate::Current();
     ASSERT(spawned_isolate != NULL);
     // Check arguments to see if the specified library and classes are
     // loaded, this check will throw an exception if they are not loaded.
     if (init_successful && CheckArguments(library_url, class_name)) {
       port_id = spawned_isolate->main_port();
       uword data = reinterpret_cast<uword>(
           new IsolateStartData(spawned_isolate,
                                strdup(library_url),
                                strdup(class_name),
@@ skipping 59 matching lines @@
   intptr_t send_id = Smi::CheckedHandle(arguments->At(0)).Value();
   intptr_t reply_id = Smi::CheckedHandle(arguments->At(1)).Value();
   // TODO(iposva): Allow for arbitrary messages to be sent.
   uint8_t* data = SerializeObject(Instance::CheckedHandle(arguments->At(2)));
 
   // TODO(turnidge): Throw an exception when the return value is false?
   PortMap::PostMessage(send_id, reply_id, Api::CastMessage(data));
 }
 
 }  // namespace dart