Removed the debug message thread

src/debug.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1402 matching lines @@
       0, NULL, &caught_exception);
 }
 
 
 Mutex* Debugger::debugger_access_ = OS::CreateMutex();
 Handle<Object> Debugger::event_listener_ = Handle<Object>();
 Handle<Object> Debugger::event_listener_data_ = Handle<Object>();
 bool Debugger::compiling_natives_ = false;
 bool Debugger::is_loading_debugger_ = false;
 bool Debugger::never_unload_debugger_ = false;
-DebugMessageThread* Debugger::message_thread_ = NULL;
 v8::Debug::MessageHandler Debugger::message_handler_ = NULL;
 bool Debugger::message_handler_cleared_ = false;
 v8::Debug::HostDispatchHandler Debugger::host_dispatch_handler_ = NULL;
 int Debugger::host_dispatch_micros_ = 100 * 1000;
 DebuggerAgent* Debugger::agent_ = NULL;
-LockingMessageQueue Debugger::command_queue_(kQueueInitialSize);
-LockingMessageQueue Debugger::message_queue_(kQueueInitialSize);
+LockingCommandMessageQueue Debugger::command_queue_(kQueueInitialSize);
 Semaphore* Debugger::command_received_ = OS::CreateSemaphore(0);
-Semaphore* Debugger::message_received_ = OS::CreateSemaphore(0);
 
 
 Handle<Object> Debugger::MakeJSObject(Vector<const char> constructor_name,
                                       int argc, Object*** argv,
                                       bool* caught_exception) {
   ASSERT(Top::context() == *Debug::debug_context());
 
   // Create the execution state object.
   Handle<String> constructor_str = Factory::LookupSymbol(constructor_name);
   Handle<Object> constructor(Top::global()->GetProperty(*constructor_str));
@@ skipping 368 matching lines @@
   v8::Local<v8::Object> cmd_processor =
       v8::Object::Cast(*fun->Call(api_exec_state, 0, NULL));
   if (try_catch.HasCaught()) {
     PrintLn(try_catch.Exception());
     return;
   }
 
   // Notify the debugger that a debug event has occurred unless auto continue is
   // active in which case no event is send.
   if (!auto_continue) {
-    bool success = SendEventMessage(event_data);
+    bool success = InvokeMessageHandlerWithEvent(event_data);
     if (!success) {
       // If failed to notify debugger just continue running.
       return;
     }
   }
 
   // Process requests from the debugger.
   while (true) {
     // Wait for new command in the queue.
     if (Debugger::host_dispatch_handler_) {
       // In case there is a host dispatch - do periodic dispatches.
       if (!command_received_->Wait(host_dispatch_micros_)) {
         // Timout expired, do the dispatch.
         Debugger::host_dispatch_handler_();
         continue;
       }
     } else {
       // In case there is no host dispatch - just wait.
       command_received_->Wait();
     }
 
     // The debug command interrupt flag might have been set when the command was
     // added.
     StackGuard::Continue(DEBUGCOMMAND);
 
     // Get the command from the queue.
-    Message command = command_queue_.Get();
+    CommandMessage command = command_queue_.Get();
     Logger::DebugTag("Got request from command queue, in interactive loop.");
     if (!Debugger::IsDebuggerActive()) {
       // Delete command text and user data.
       command.Dispose();
       return;
     }
 
     // Invoke JavaScript to process the debug request.
     v8::Local<v8::String> fun_name;
     v8::Local<v8::Function> fun;
@@ skipping 34 matching lines @@
       v8::Local<v8::Value> running_val = fun->Call(cmd_processor, kArgc, argv);
       if (!try_catch.HasCaught()) {
         running = running_val->ToBoolean()->Value();
       }
     } else {
       // In case of failure the result text is the exception text.
       response = try_catch.Exception()->ToString();
     }
 
     // Return the result.
-    SendMessage(Message::NewOutput(response, command.client_data()));
+    InvokeMessageHandler(response, command.client_data());
 
     // Return from debug event processing if either the VM is put into the
     // runnning state (through a continue command) or auto continue is active
     // and there are no more commands queued.
     if (running || (auto_continue && !HasCommands())) {
       return;
     }
   }
 }
 
@@ skipping 25 matching lines @@
     event_listener_data_ = Handle<Object>::cast(GlobalHandles::Create(*data));
   }
 
   // Unload the debugger if event listener cleared.
   if (callback->IsUndefined()) {
     UnloadDebugger();
   }
 }
 
 
-void Debugger::SetMessageHandler(v8::Debug::MessageHandler handler,
-                                 bool message_handler_thread) {
+void Debugger::SetMessageHandler(v8::Debug::MessageHandler handler) {
   ScopedLock with(debugger_access_);
 
   message_handler_ = handler;
-  if (handler != NULL) {
-    if (!message_thread_ && message_handler_thread) {
-      message_thread_ = new DebugMessageThread();
-      message_thread_->Start();
-    }
-  } else {
+  if (handler == NULL) {
     // Indicate that the message handler was recently cleared.
     message_handler_cleared_ = true;
 
     // Send an empty command to the debugger if in a break to make JavaScript
     // run again if the debugger is closed.
     if (Debug::InDebugger()) {
       ProcessCommand(Vector<const uint16_t>::empty());
     }
   }
 }
 
 
 void Debugger::SetHostDispatchHandler(v8::Debug::HostDispatchHandler handler,
                                       int period) {
   host_dispatch_handler_ = handler;
   host_dispatch_micros_ = period * 1000;
 }
 
 
 // Calls the registered debug message handler. This callback is part of the
 // public API. Messages are kept internally as Vector<uint16_t> strings, which
 // are allocated in various places and deallocated by the calling function
 // sometime after this call.
-void Debugger::InvokeMessageHandler(Message message) {
+void Debugger::InvokeMessageHandler(v8::Handle<v8::String> output,
+                                    v8::Debug::ClientData* data) {
   ScopedLock with(debugger_access_);
 
   if (message_handler_ != NULL) {
-    message_handler_(message.text().start(),
-                     message.text().length(),
-                     message.client_data());
+    Vector<uint16_t> text = Vector<uint16_t>::New(output->Length());
+    output->Write(text.start(), 0, output->Length());
+
+    message_handler_(text.start(),
+                     text.length(),
+                     data);
+
+    text.Dispose();
   }
-  message.Dispose();
+  delete data;
 }
 
 
-void Debugger::SendMessage(Message message) {
-  if (message_thread_ == NULL) {
-    // If there is no message thread just invoke the message handler from the
-    // V8 thread.
-    InvokeMessageHandler(message);
-  } else {
-    // Put the message coming from V8 on the queue. The text and user data will
-    // be destroyed by the message thread.
-    Logger::DebugTag("Put message on event message_queue.");
-    message_queue_.Put(message);
-    message_received_->Signal();
-  }
-}
-
-
-bool Debugger::SendEventMessage(Handle<Object> event_data) {
+bool Debugger::InvokeMessageHandlerWithEvent(Handle<Object> event_data) {
   v8::HandleScope scope;
   // Call toJSONProtocol on the debug event object.
   v8::Local<v8::Object> api_event_data =
       v8::Utils::ToLocal(Handle<JSObject>::cast(event_data));
   v8::Local<v8::String> fun_name = v8::String::New("toJSONProtocol");
   v8::Local<v8::Function> fun =
       v8::Function::Cast(*api_event_data->Get(fun_name));
   v8::TryCatch try_catch;
   v8::Local<v8::Value> json_event = *fun->Call(api_event_data, 0, NULL);
   v8::Local<v8::String> json_event_string;
   if (!try_catch.HasCaught()) {
     if (!json_event->IsUndefined()) {
       json_event_string = json_event->ToString();
       if (FLAG_trace_debug_json) {
         PrintLn(json_event_string);
       }
-      SendMessage(Message::NewOutput(
-          json_event_string,
-          NULL /* no user data since there was no request */));
+      InvokeMessageHandler(json_event_string,
+                           NULL /* no user data since there was no request */);
     } else {
-      SendMessage(Message::NewEmptyMessage());
+      InvokeMessageHandler(v8::String::Empty(), NULL);
     }
   } else {
     PrintLn(try_catch.Exception());
     return false;
   }
   return true;
 }
 
 
 // Puts a command coming from the public API on the queue.  Creates
 // a copy of the command string managed by the debugger.  Up to this
 // point, the command data was managed by the API client.  Called
-// by the API client thread.  This is where the API client hands off
-// processing of the command to the DebugMessageThread thread.
-// The new copy of the command is destroyed in HandleCommand().
+// by the API client thread.
 void Debugger::ProcessCommand(Vector<const uint16_t> command,
                               v8::Debug::ClientData* client_data) {
   // Need to cast away const.
-  Message message = Message::NewCommand(
+  CommandMessage message = CommandMessage::New(
       Vector<uint16_t>(const_cast<uint16_t*>(command.start()),
                        command.length()),
       client_data);
   Logger::DebugTag("Put command on command_queue.");
   command_queue_.Put(message);
   command_received_->Signal();
 
   // Set the debug command break flag to have the command processed.
   if (!Debug::InDebugger()) {
     StackGuard::DebugCommand();
@@ skipping 54 matching lines @@
 void Debugger::StopAgent() {
   if (agent_ != NULL) {
     agent_->Shutdown();
     agent_->Join();
     delete agent_;
     agent_ = NULL;
   }
 }
 
 
-void Debugger::TearDown() {
-  if (message_thread_ != NULL) {
-    message_thread_->Stop();
-    delete message_thread_;
-    message_thread_ = NULL;
-  }
+CommandMessage::CommandMessage() : text_(Vector<uint16_t>::empty()),
+                                   client_data_(NULL) {
 }
 
 
-void DebugMessageThread::Run() {
-  // Sends debug events to an installed debugger message callback.
-  while (keep_running_) {
-    // Wait and Get are paired so that semaphore count equals queue length.
-    Debugger::message_received_->Wait();
-    Logger::DebugTag("Get message from event message_queue.");
-    Message message = Debugger::message_queue_.Get();
-    if (message.text().length() > 0) {
-      Debugger::InvokeMessageHandler(message);
-    } else {
-      message.Dispose();
-    }
-  }
-}
-
-
-void DebugMessageThread::Stop() {
-  keep_running_ = false;
-  Debugger::SendMessage(Message::NewEmptyMessage());
-  Join();
-}
-
-
-Message::Message() : text_(Vector<uint16_t>::empty()),
-                     client_data_(NULL) {
-}
-
-
-Message::Message(const Vector<uint16_t>& text,
-                 v8::Debug::ClientData* data)
+CommandMessage::CommandMessage(const Vector<uint16_t>& text,
+                               v8::Debug::ClientData* data)
     : text_(text),
       client_data_(data) {
 }
 
 
-Message::~Message() {
+CommandMessage::~CommandMessage() {
 }
 
 
-void Message::Dispose() {
+void CommandMessage::Dispose() {
   text_.Dispose();
   delete client_data_;
   client_data_ = NULL;
 }
 
 
-Message Message::NewCommand(const Vector<uint16_t>& command,
-                            v8::Debug::ClientData* data) {
-  return Message(command.Clone(), data);
+CommandMessage CommandMessage::New(const Vector<uint16_t>& command,
+                                   v8::Debug::ClientData* data) {
+  return CommandMessage(command.Clone(), data);
 }
 
 
-Message Message::NewOutput(v8::Handle<v8::String> output,
-                           v8::Debug::ClientData* data) {
-  Vector<uint16_t> text;
-  if (!output.IsEmpty()) {
-    // Do not include trailing '\0'.
-    text = Vector<uint16_t>::New(output->Length());
-    output->Write(text.start(), 0, output->Length());
-  }
-  return Message(text, data);
+CommandMessageQueue::CommandMessageQueue(int size) : start_(0), end_(0),
+                                                     size_(size) {
+  messages_ = NewArray<CommandMessage>(size);
 }
 
 
-Message Message::NewEmptyMessage() {
-  return Message();
-}
-
-
-MessageQueue::MessageQueue(int size) : start_(0), end_(0), size_(size) {
-  messages_ = NewArray<Message>(size);
-}
-
-
-MessageQueue::~MessageQueue() {
+CommandMessageQueue::~CommandMessageQueue() {
   while (!IsEmpty()) {
-    Message m = Get();
+    CommandMessage m = Get();
     m.Dispose();
   }
   DeleteArray(messages_);
 }
 
 
-Message MessageQueue::Get() {
+CommandMessage CommandMessageQueue::Get() {
   ASSERT(!IsEmpty());
   int result = start_;
   start_ = (start_ + 1) % size_;
   return messages_[result];
 }
 
 
-void MessageQueue::Put(const Message& message) {
+void CommandMessageQueue::Put(const CommandMessage& message) {
   if ((end_ + 1) % size_ == start_) {
     Expand();
   }
   messages_[end_] = message;
   end_ = (end_ + 1) % size_;
 }
 
 
-void MessageQueue::Expand() {
-  MessageQueue new_queue(size_ * 2);
+void CommandMessageQueue::Expand() {
+  CommandMessageQueue new_queue(size_ * 2);
   while (!IsEmpty()) {
     new_queue.Put(Get());
   }
-  Message* array_to_free = messages_;
+  CommandMessage* array_to_free = messages_;
   *this = new_queue;
   new_queue.messages_ = array_to_free;
   // Make the new_queue empty so that it doesn't call Dispose on any messages.
   new_queue.start_ = new_queue.end_;
   // Automatic destructor called on new_queue, freeing array_to_free.
 }
 
 
-LockingMessageQueue::LockingMessageQueue(int size) : queue_(size) {
+LockingCommandMessageQueue::LockingCommandMessageQueue(int size)
+    : queue_(size) {
   lock_ = OS::CreateMutex();
 }
 
 
-LockingMessageQueue::~LockingMessageQueue() {
+LockingCommandMessageQueue::~LockingCommandMessageQueue() {
   delete lock_;
 }
 
 
-bool LockingMessageQueue::IsEmpty() const {
+bool LockingCommandMessageQueue::IsEmpty() const {
   ScopedLock sl(lock_);
   return queue_.IsEmpty();
 }
 
 
-Message LockingMessageQueue::Get() {
+CommandMessage LockingCommandMessageQueue::Get() {
   ScopedLock sl(lock_);
-  Message result = queue_.Get();
+  CommandMessage result = queue_.Get();
   Logger::DebugEvent("Get", result.text());
   return result;
 }
 
 
-void LockingMessageQueue::Put(const Message& message) {
+void LockingCommandMessageQueue::Put(const CommandMessage& message) {
   ScopedLock sl(lock_);
   queue_.Put(message);
   Logger::DebugEvent("Put", message.text());
 }
 
 
-void LockingMessageQueue::Clear() {
+void LockingCommandMessageQueue::Clear() {
   ScopedLock sl(lock_);
   queue_.Clear();
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal