Fix disabling all break points from within the debug event callback.

src/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_H_
 #define V8_DEBUG_H_
 
 #include "src/allocation.h"
 #include "src/arguments.h"
 #include "src/assembler.h"
@@ skipping 497 matching lines @@
 
   void UpdateState();
   void Unload();
   void SetNextBreakId() {
     thread_local_.break_id_ = ++thread_local_.break_count_;
   }
 
   // Check whether there are commands in the command queue.
   inline bool has_commands() const { return !command_queue_.IsEmpty(); }
   inline bool ignore_events() const { return is_suppressed_ || !is_active_; }
+  inline bool break_disabled() const {
+    return break_disabled_ || break_disabled_for_event_;
+  }
 
   void OnException(Handle<Object> exception, bool uncaught,
                    Handle<Object> promise);
 
   // Constructors for debug event objects.
   MUST_USE_RESULT MaybeHandle<Object> MakeJSObject(
       const char* constructor_name,
       int argc,
       Handle<Object> argv[]);
   MUST_USE_RESULT MaybeHandle<Object> MakeExecutionState();
@@ skipping 57 matching lines @@
   static const int kQueueInitialSize = 4;
   base::Semaphore command_received_;  // Signaled for each command received.
   LockingCommandMessageQueue command_queue_;
   LockingCommandMessageQueue event_command_queue_;
 
   bool is_active_;
   bool is_suppressed_;
   bool live_edit_enabled_;
   bool has_break_points_;
   bool break_disabled_;
+  bool break_disabled_for_event_;

[yurys, 2014/11/18 12:53:33]

I'd rather call it something like in_debug_listener_ which would better reflect
current state.

   bool break_on_exception_;
   bool break_on_uncaught_exception_;
 
   ScriptCache* script_cache_;  // Cache of all scripts in the heap.
   DebugInfoListNode* debug_info_list_;  // List of active debug info objects.
 
   // Storage location for jump when exiting debug break calls.
   // Note that this address is not GC safe.  It should be computed immediately
   // before returning to the DebugBreakCallHelper.
   Address after_break_target_;
@@ skipping 90 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, bool disable_break)
-    : debug_(debug), old_state_(debug->break_disabled_) {
+      : debug_(debug),
+        previous_break_disabled_(debug->break_disabled_),
+        previous_break_disabled_for_event_(debug->break_disabled_for_event_) {
     debug_->break_disabled_ = disable_break;
+    debug_->break_disabled_for_event_ = disable_break;
   }
-  ~DisableBreak() { debug_->break_disabled_ = old_state_; }
+  ~DisableBreak() {
+    debug_->break_disabled_ = previous_break_disabled_;
+    debug_->break_disabled_for_event_ = previous_break_disabled_for_event_;
+  }
 
  private:
   Debug* debug_;
-  bool old_state_;
+  bool previous_break_disabled_ : 1;

[yurys, 2014/11/18 12:53:33]

Does it really make sense to use bit fields here? To my taste they just distract
reader of the code.

+  bool previous_break_disabled_for_event_ : 1;
   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 27 matching lines @@
   // several frames above.
   // There is no calling conventions here, because it never actually gets
   // called, it only gets returned to.
   static void GenerateFrameDropperLiveEdit(MacroAssembler* masm);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_DEBUG_H_