From aefcf999d23d5d3465cee60be8c8db96c8edd08f Mon Sep 17 00:00:00 2001
From: Johnny Chen <johnny.chen@apple.com>
Date: Fri, 27 Jan 2012 21:27:39 +0000
Subject: [PATCH] Add an InstanceSettings::NotifyOwnerIsShuttingDown() method
 so that the owner can notify InstanceSettings instances that their owner
 reference is no longer valid.

llvm-svn: 149145
---
 lldb/include/lldb/Core/UserSettingsController.h |  4 ++++
 lldb/source/Core/UserSettingsController.cpp     | 15 +++++++++++++--
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/lldb/include/lldb/Core/UserSettingsController.h b/lldb/include/lldb/Core/UserSettingsController.h
index 2e3d182d3549..878abd20dddb 100644
--- a/lldb/include/lldb/Core/UserSettingsController.h
+++ b/lldb/include/lldb/Core/UserSettingsController.h
@@ -399,6 +399,9 @@ public:
 
     // Begin Pure Virtual Functions
 
+    virtual void
+    NotifyOwnerIsShuttingDown ();
+
     virtual void
     UpdateInstanceSettingsVariable (const ConstString &var_name,
                                     const char *index_value,
@@ -440,6 +443,7 @@ public:
 protected:
 
     UserSettingsController &m_owner;
+    bool m_owner_is_live;
     ConstString m_instance_name;
 };
 
diff --git a/lldb/source/Core/UserSettingsController.cpp b/lldb/source/Core/UserSettingsController.cpp
index de3a71dd59ee..cdacad020e6a 100644
--- a/lldb/source/Core/UserSettingsController.cpp
+++ b/lldb/source/Core/UserSettingsController.cpp
@@ -83,6 +83,10 @@ UserSettingsController::UserSettingsController (const char *level_name,
 UserSettingsController::~UserSettingsController ()
 {
     Mutex::Locker locker (m_live_settings_mutex);
+
+    // Notify all instance settings that their owner is shutting down, first.
+    for (InstanceSettingsMap::iterator pos = m_live_settings.begin(); pos != m_live_settings.end(); ++pos)
+        pos->second->NotifyOwnerIsShuttingDown();
     m_live_settings.clear();
 }
 
@@ -2458,7 +2462,8 @@ UserSettingsController::RenameInstanceSettings (const char *old_name, const char
 
 InstanceSettings::InstanceSettings (UserSettingsController &owner, const char *instance_name, bool live_instance) :
     m_owner (owner),
-    m_instance_name (instance_name)
+    m_instance_name (instance_name),
+    m_owner_is_live (true)
 {
     if ((m_instance_name != InstanceSettings::GetDefaultName())
         && (m_instance_name !=  InstanceSettings::InvalidName())
@@ -2468,10 +2473,16 @@ InstanceSettings::InstanceSettings (UserSettingsController &owner, const char *i
 
 InstanceSettings::~InstanceSettings ()
 {
-    if (m_instance_name != InstanceSettings::GetDefaultName())
+    if (m_instance_name != InstanceSettings::GetDefaultName() && m_owner_is_live)
         m_owner.UnregisterInstanceSettings (this);
 }
 
+void
+InstanceSettings::NotifyOwnerIsShuttingDown()
+{
+    m_owner_is_live = false;
+}
+
 const ConstString &
 InstanceSettings::GetDefaultName ()
 {