Add remote debugging front end to developer shell....

src/d8-debug.h

Index: src/d8-debug.h
===================================================================
--- src/d8-debug.h	(revision 1405)
+++ src/d8-debug.h	(working copy)
@@ -41,7 +41,114 @@
                       Handle<Object> event_data,
                       Handle<Value> data);
 
+// Start the remove debugger connecting to a V8 debugger agent on the specified
+// port.
+void RunRemoteDebugger(int port);
 
+// Forward declerations.
+class RemoteDebuggerEvent;
+class ReceiverThread;
+
+
+// Remote debugging class.
+class RemoteDebugger {
+ public:
+  explicit RemoteDebugger(int port)
+      : port_(port),
+        event_access_(i::OS::CreateMutex()),
+        event_available_(i::OS::CreateSemaphore(0)),
+        head_(NULL), tail_(NULL) {}
+  void Run();
+
+  // Handle events from the subordinate threads.
+  void MessageReceived(i::SmartPointer<char> message);
+  void KeyboardCommand(i::SmartPointer<char> command);
+  void ConnectionClosed();
+
+ private:
+  // Add new debugger event to the list.
+  void AddEvent(RemoteDebuggerEvent* event);
+  // Read next debugger event from the list.
+  RemoteDebuggerEvent* GetEvent();
+
+  // Handle a message from the debugged V8.
+  void HandleMessageReceived(char* message);
+  // Handle a keyboard command.
+  void HandleKeyboardCommand(char* command);
+
+  // Get connection to agent in debugged V8.
+  i::Socket* conn() { return conn_; }
+
+  int port_;  // Port used to connect to debugger V8.
+  i::Socket* conn_;  // Connection to debugger agent in debugged V8.
+
+  // Linked list of events from debugged V8 and from keyboard input. Access to
+  // the list is guarded by a mutex and a semaphore signals new items in the
+  // list.
+  i::Mutex* event_access_;
+  i::Semaphore* event_available_;
+  RemoteDebuggerEvent* head_;
+  RemoteDebuggerEvent* tail_;
+
+  friend class ReceiverThread;
+};
+
+
+// Thread reading from debugged V8 instance.
+class ReceiverThread: public i::Thread {
+ public:
+  explicit ReceiverThread(RemoteDebugger* remote_debugger)
+      : remote_debugger_(remote_debugger) {}
+  ~ReceiverThread() {}
+
+  void Run();
+
+ private:
+  RemoteDebugger* remote_debugger_;
+};
+
+
+// Thread reading keyboard input.
+class KeyboardThread: public i::Thread {
+ public:
+  explicit KeyboardThread(RemoteDebugger* remote_debugger)
+      : remote_debugger_(remote_debugger) {}
+  ~KeyboardThread() {}
+
+  void Run();
+
+ private:
+  RemoteDebugger* remote_debugger_;
+};
+
+
+// Events processed by the main deubgger thread.
+class RemoteDebuggerEvent {
+ public:
+  RemoteDebuggerEvent(int type, i::SmartPointer<char> data)
+      : type_(type), data_(data), next_(NULL) {
+    ASSERT(type == kMessage || type == kKeyboard || type == kDisconnect);
+  }
+
+  static const int kMessage = 1;
+  static const int kKeyboard = 2;
+  static const int kDisconnect = 3;
+
+  int type() { return type_; }
+  char* data() { return *data_; }
+
+ private:
+  void set_next(RemoteDebuggerEvent* event) { next_ = event; }
+  RemoteDebuggerEvent* next() { return next_; }
+
+  int type_;
+  i::SmartPointer<char> data_;
+  RemoteDebuggerEvent* next_;
+
+  friend class RemoteDebugger;
+};
+
+
 }  // namespace v8