[debugger] implement legacy debug event listeners via debug delegate.

src/debug/debug.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_DEBUG_DEBUG_H_
 #define V8_DEBUG_DEBUG_H_
 
 #include "src/allocation.h"
 #include "src/arguments.h"
 #include "src/assembler.h"
@@ skipping 213 matching lines @@
   Handle<DebugInfo> debug_info() { return Handle<DebugInfo>(debug_info_); }
 
  private:
   // Global (weak) handle to the debug info object.
   DebugInfo** debug_info_;
 
   // Next pointer for linked list.
   DebugInfoListNode* next_;
 };
 
-// Details of the debug event delivered to the debug event listener.
-class EventDetailsImpl : public v8::Debug::EventDetails {
- public:
-  EventDetailsImpl(DebugEvent event, Handle<JSObject> exec_state,
-                   Handle<JSObject> event_data, Handle<Object> callback_data);
-  virtual DebugEvent GetEvent() const;
-  virtual v8::Local<v8::Object> GetExecutionState() const;
-  virtual v8::Local<v8::Object> GetEventData() const;
-  virtual v8::Local<v8::Context> GetEventContext() const;
-  virtual v8::Local<v8::Value> GetCallbackData() const;
-  virtual v8::Debug::ClientData* GetClientData() const { return nullptr; }
-  virtual v8::Isolate* GetIsolate() const;
-
- private:
-  DebugEvent event_;  // Debug event causing the break.
-  Handle<JSObject> exec_state_;         // Current execution state.
-  Handle<JSObject> event_data_;         // Data associated with the event.
-  Handle<Object> callback_data_;        // User data passed with the callback
-                                        // when it was registered.
-};
-
-
 class DebugFeatureTracker {
  public:
   enum Feature {
     kActive = 1,
     kBreakPoint = 2,
     kStepping = 3,
     kHeapSnapshot = 4,
     kAllocationTracking = 5,
     kProfiler = 6,
     kLiveEdit = 7,
@@ skipping 18 matching lines @@
 // DebugInfo.
 class Debug {
  public:
   // Debug event triggers.
   void OnDebugBreak(Handle<Object> break_points_hit);
 
   void OnThrow(Handle<Object> exception);
   void OnPromiseReject(Handle<Object> promise, Handle<Object> value);
   void OnCompileError(Handle<Script> script);
   void OnAfterCompile(Handle<Script> script);
-  void OnAsyncTaskEvent(debug::PromiseDebugActionType type, int id);
+  void OnAsyncTaskEvent(debug::PromiseDebugActionType type, int id,
+                        int parent_id);
 
-  // API facing.
-  void SetEventListener(Handle<Object> callback, Handle<Object> data);
   MUST_USE_RESULT MaybeHandle<Object> Call(Handle<Object> fun,
                                            Handle<Object> data);
   Handle<Context> GetDebugContext();
   void HandleDebugBreak();
 
   // Internal logic
   bool Load();
   void Break(JavaScriptFrame* frame);
 
   // Scripts handling.
@@ skipping 32 matching lines @@
 
   void RecordGenerator(Handle<JSGeneratorObject> generator_object);
 
   void RunPromiseHook(PromiseHookType type, Handle<JSPromise> promise,
                       Handle<Object> parent);
 
   int NextAsyncTaskId(Handle<JSObject> promise);
 
   bool IsBlackboxed(Handle<SharedFunctionInfo> shared);
 
-  void SetDebugDelegate(debug::DebugDelegate* delegate);
+  void SetDebugDelegate(debug::DebugDelegate* delegate, bool pass_ownership);
 
   // Returns whether the operation succeeded.
   bool EnsureDebugInfo(Handle<SharedFunctionInfo> shared);
   void CreateDebugInfo(Handle<SharedFunctionInfo> shared);
   static Handle<DebugInfo> GetDebugInfo(Handle<SharedFunctionInfo> shared);
 
   template <typename C>
   bool CompileToRevealInnerFunctions(C* compilable);
 
   // This function is used in FunctionNameUsing* tests.
@@ skipping 79 matching lines @@
   Address restart_fp_address() {
     return reinterpret_cast<Address>(&thread_local_.restart_fp_);
   }
 
   StepAction last_step_action() { return thread_local_.last_step_action_; }
 
   DebugFeatureTracker* feature_tracker() { return &feature_tracker_; }
 
  private:
   explicit Debug(Isolate* isolate);
+  ~Debug() { DCHECK_NULL(debug_delegate_); }
 
   void UpdateState();
   void UpdateHookOnFunctionCall();
+  void RemoveDebugDelegate();
   void Unload();
   void SetNextBreakId() {
     thread_local_.break_id_ = ++thread_local_.break_count_;
   }
 
   // Return the number of virtual frames below debugger entry.
   int CurrentFrameCount();
 
   inline bool ignore_events() const {
     return is_suppressed_ || !is_active_ || isolate_->needs_side_effect_check();
   }
-  inline bool break_disabled() const {
-    return break_disabled_ || in_debug_event_listener_;
-  }
+  inline bool break_disabled() const { return break_disabled_; }
 
   void clear_suspended_generator() {
     thread_local_.suspended_generator_ = Smi::kZero;
   }
 
   bool has_suspended_generator() const {
     return thread_local_.suspended_generator_ != Smi::kZero;
   }
 
-  // There are three types of event listeners: C++ message_handler,
-  // JavaScript event listener and C++ event listener.
-  // Currently inspector still uses C++ event listener and installs
-  // more specific event listeners for part of events. Calling of
-  // C++ event listener is redundant when more specific event listener
-  // is presented. Other clients can install JavaScript event listener
-  // (e.g. some of NodeJS module).
-  bool non_inspector_listener_exists() const {
-    return !event_listener_.is_null() && !event_listener_->IsForeign();
-  }
-
   bool IsExceptionBlackboxed(bool uncaught);
 
   void OnException(Handle<Object> exception, Handle<Object> promise);
 
   // Constructors for debug event objects.
   MUST_USE_RESULT MaybeHandle<Object> MakeExecutionState();
   MUST_USE_RESULT MaybeHandle<Object> MakeBreakEvent(
       Handle<Object> break_points_hit);
   MUST_USE_RESULT MaybeHandle<Object> MakeExceptionEvent(
       Handle<Object> exception,
       bool uncaught,
       Handle<Object> promise);
   MUST_USE_RESULT MaybeHandle<Object> MakeCompileEvent(
       Handle<Script> script, v8::DebugEvent type);
-  MUST_USE_RESULT MaybeHandle<Object> MakeAsyncTaskEvent(Handle<Smi> type,
-                                                         Handle<Smi> id);
+  MUST_USE_RESULT MaybeHandle<Object> MakeAsyncTaskEvent(
+      v8::debug::PromiseDebugActionType type, int id);
 
   void ProcessCompileEvent(v8::DebugEvent event, Handle<Script> script);
   void ProcessDebugEvent(v8::DebugEvent event, Handle<JSObject> event_data);
 
   // Find the closest source position for a break point for a given position.
   int FindBreakablePosition(Handle<DebugInfo> debug_info, int source_position,
                             BreakPositionAlignment alignment);
   // Instrument code to break at break points.
   void ApplyBreakPoints(Handle<DebugInfo> debug_info);
   // Clear code from instrumentation.
@@ skipping 20 matching lines @@
     DCHECK(in_debug_scope());
   }
 
   void ThreadInit();
 
   void PrintBreakLocation();
 
   // Global handles.
   Handle<Context> debug_context_;
   Handle<Object> event_listener_;
   Handle<Object> event_listener_data_;

[jgruber, 2017/02/09 10:33:28]

Can we remove event_listener{,_data}_?

 
   debug::DebugDelegate* debug_delegate_ = nullptr;
+  bool owns_debug_delegate_ = false;
 
   // Debugger is active, i.e. there is a debug event listener attached.
   bool is_active_;
   // Debugger needs to be notified on every new function call.
   // Used for stepping and read-only checks
   bool hook_on_function_call_;
   // Suppress debug events.
   bool is_suppressed_;
   // LiveEdit is enabled.
   bool live_edit_enabled_;
   // Do not trigger debug break events.
   bool break_disabled_;
   // Do not break on break points.
   bool break_points_active_;
-  // Nested inside a debug event listener.
-  bool in_debug_event_listener_;
   // Trigger debug break events for all exceptions.
   bool break_on_exception_;
   // Trigger debug break events for uncaught exceptions.
   bool break_on_uncaught_exception_;
   // Termination exception because side effect check has failed.
   bool side_effect_check_failed_;
 
   // List of active debug info objects.
   DebugInfoListNode* debug_info_list_;
 
@@ skipping 43 matching lines @@
   ThreadLocal thread_local_;
 
   Isolate* isolate_;
 
   friend class Isolate;
   friend class DebugScope;
   friend class DisableBreak;
   friend class LiveEdit;
   friend class SuppressDebug;
   friend class NoSideEffectScope;
+  friend class LegacyDebugDelegate;
 
   friend Handle<FixedArray> GetDebuggedFunctions();  // In test-debug.cc
   friend void CheckDebuggerUnloaded(bool check_functions);  // In test-debug.cc
 
   DISALLOW_COPY_AND_ASSIGN(Debug);
 };
 
+class LegacyDebugDelegate : public v8::debug::DebugDelegate {
+ public:
+  explicit LegacyDebugDelegate(Isolate* isolate) : isolate_(isolate) {}
+  void PromiseEventOccurred(v8::debug::PromiseDebugActionType type, int id,
+                            int parent_id) override;
+  void ScriptCompiled(v8::Local<v8::debug::Script> script,
+                      bool has_compile_error) override;
+  void BreakProgramRequested(v8::Local<v8::Context> paused_context,
+                             v8::Local<v8::Object> exec_state,
+                             v8::Local<v8::Value> break_points_hit) override;
+  void ExceptionThrown(v8::Local<v8::Context> paused_context,
+                       v8::Local<v8::Object> exec_state,
+                       v8::Local<v8::Value> exception,
+                       v8::Local<v8::Value> promise, bool is_uncaught) override;
+  bool IsFunctionBlackboxed(v8::Local<v8::debug::Script> script,
+                            const v8::debug::Location& start,
+                            const v8::debug::Location& end) override {
+    return false;
+  }
+
+ protected:
+  Isolate* isolate_;
+
+ private:
+  void ProcessDebugEvent(v8::DebugEvent event, Handle<JSObject> event_data);
+  virtual void ProcessDebugEvent(v8::DebugEvent event,
+                                 Handle<JSObject> event_data,
+                                 Handle<JSObject> exec_state) = 0;
+};
+
+class JavaScriptDebugDelegate : public LegacyDebugDelegate {
+ public:
+  JavaScriptDebugDelegate(Isolate* isolate, Handle<JSFunction> listener,
+                          Handle<Object> data);
+  virtual ~JavaScriptDebugDelegate();
+
+ private:
+  void ProcessDebugEvent(v8::DebugEvent event, Handle<JSObject> event_data,
+                         Handle<JSObject> exec_state) override;
+
+  Handle<JSFunction> listener_;
+  Handle<Object> data_;
+};
+
+class NativeDebugDelegate : public LegacyDebugDelegate {
+ public:
+  NativeDebugDelegate(Isolate* isolate, v8::Debug::EventCallback callback,
+                      Handle<Object> data);
+  virtual ~NativeDebugDelegate();
+
+ private:
+  // Details of the debug event delivered to the debug event listener.
+  class EventDetails : public v8::Debug::EventDetails {
+   public:
+    EventDetails(DebugEvent event, Handle<JSObject> exec_state,
+                 Handle<JSObject> event_data, Handle<Object> callback_data);
+    virtual DebugEvent GetEvent() const;
+    virtual v8::Local<v8::Object> GetExecutionState() const;
+    virtual v8::Local<v8::Object> GetEventData() const;
+    virtual v8::Local<v8::Context> GetEventContext() const;
+    virtual v8::Local<v8::Value> GetCallbackData() const;
+    virtual v8::Debug::ClientData* GetClientData() const { return nullptr; }
+    virtual v8::Isolate* GetIsolate() const;
+
+   private:
+    DebugEvent event_;              // Debug event causing the break.
+    Handle<JSObject> exec_state_;   // Current execution state.
+    Handle<JSObject> event_data_;   // Data associated with the event.
+    Handle<Object> callback_data_;  // User data passed with the callback
+                                    // when it was registered.
+  };
+
+  void ProcessDebugEvent(v8::DebugEvent event, Handle<JSObject> event_data,
+                         Handle<JSObject> exec_state) override;
+
+  v8::Debug::EventCallback callback_;
+  Handle<Object> data_;
+};
 
 // This scope is used to load and enter the debug context and create a new
 // break state.  Leaving the scope will restore the previous state.
 // On failure to load, FailedToEnter returns true.
 class DebugScope BASE_EMBEDDED {
  public:
   explicit DebugScope(Debug* debug);
   ~DebugScope();
 
   // Check whether loading was successful.
@@ skipping 13 matching lines @@
   bool failed_;                    // Did the debug context fail to load?
   SaveContext save_;               // Saves previous context.
   PostponeInterruptsScope no_termination_exceptons_;
 };
 
 
 // Stack allocated class for disabling break.
 class DisableBreak BASE_EMBEDDED {
  public:
   explicit DisableBreak(Debug* debug)
-      : debug_(debug),
-        previous_break_disabled_(debug->break_disabled_),
-        previous_in_debug_event_listener_(debug->in_debug_event_listener_) {
+      : debug_(debug), previous_break_disabled_(debug->break_disabled_) {
     debug_->break_disabled_ = true;
-    debug_->in_debug_event_listener_ = true;
   }
   ~DisableBreak() {
     debug_->break_disabled_ = previous_break_disabled_;
-    debug_->in_debug_event_listener_ = previous_in_debug_event_listener_;
   }
 
  private:
   Debug* debug_;
   bool previous_break_disabled_;
-  bool previous_in_debug_event_listener_;
   DISALLOW_COPY_AND_ASSIGN(DisableBreak);
 };
 
 
 class SuppressDebug BASE_EMBEDDED {
  public:
   explicit SuppressDebug(Debug* debug)
       : debug_(debug), old_state_(debug->is_suppressed_) {
     debug_->is_suppressed_ = true;
   }
@@ skipping 47 matching lines @@
                                   Handle<Code> code);
   static bool DebugBreakSlotIsPatched(Address pc);
   static void ClearDebugBreakSlot(Isolate* isolate, Address pc);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_DEBUG_DEBUG_H_