From 6e589e2bb31e8ef0391f47217dcb495284e1dc00 Mon Sep 17 00:00:00 2001
From: Matthias Koefferlein <matthias@klayout.de>
Date: Sun, 19 Nov 2023 21:14:32 +0100
Subject: [PATCH] Fixed issue #1533 (KLayout crashing with two consecutive
 calls of the same LayoutView::show_layout command)

---
 .../laybasic/gsiDeclLayLayoutViewBase.cc      | 15 +++++++++++---
 src/laybasic/laybasic/layCellView.cc          | 15 ++++++++++++++
 src/laybasic/laybasic/layCellView.h           |  8 ++++++++
 testdata/ruby/layLayoutView.rb                | 20 +++++++++++++++++++
 4 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/src/laybasic/laybasic/gsiDeclLayLayoutViewBase.cc b/src/laybasic/laybasic/gsiDeclLayLayoutViewBase.cc
index 39dbe2404..5e9af3dd0 100644
--- a/src/laybasic/laybasic/gsiDeclLayLayoutViewBase.cc
+++ b/src/laybasic/laybasic/gsiDeclLayLayoutViewBase.cc
@@ -277,7 +277,10 @@ static unsigned int show_layout1 (lay::LayoutViewBase *view, db::Layout *layout,
 {
   //  the layout gets held by the LayoutHandle object
   layout->keep ();
-  lay::LayoutHandle *handle = new lay::LayoutHandle (layout, std::string ());
+  lay::LayoutHandle *handle = lay::LayoutHandle::find_layout (layout);
+  if (! handle) {
+    handle = new lay::LayoutHandle (layout, std::string ());
+  }
   return view->add_layout (handle, add_cellview);
 }
 
@@ -285,7 +288,10 @@ static unsigned int show_layout2 (lay::LayoutViewBase *view, db::Layout *layout,
 {
   //  the layout gets held by the LayoutHandle object
   layout->keep ();
-  lay::LayoutHandle *handle = new lay::LayoutHandle (layout, std::string ());
+  lay::LayoutHandle *handle = lay::LayoutHandle::find_layout (layout);
+  if (! handle) {
+    handle = new lay::LayoutHandle (layout, std::string ());
+  }
   handle->set_tech_name (tech);
   return view->add_layout (handle, add_cellview);
 }
@@ -294,7 +300,10 @@ static unsigned int show_layout3 (lay::LayoutViewBase *view, db::Layout *layout,
 {
   //  the layout gets held by the LayoutHandle object
   layout->keep ();
-  lay::LayoutHandle *handle = new lay::LayoutHandle (layout, std::string ());
+  lay::LayoutHandle *handle = lay::LayoutHandle::find_layout (layout);
+  if (! handle) {
+    handle = new lay::LayoutHandle (layout, std::string ());
+  }
   handle->set_tech_name (tech);
   return view->add_layout (handle, add_cellview, initialize_layers);
 }
diff --git a/src/laybasic/laybasic/layCellView.cc b/src/laybasic/laybasic/layCellView.cc
index d0afaa103..55c97743f 100644
--- a/src/laybasic/laybasic/layCellView.cc
+++ b/src/laybasic/laybasic/layCellView.cc
@@ -272,6 +272,17 @@ LayoutHandle::find (const std::string &name)
   }
 }
 
+LayoutHandle *
+LayoutHandle::find_layout (const db::Layout *layout)
+{
+  for (auto h = ms_dict.begin (); h != ms_dict.end (); ++h) {
+    if (h->second->mp_layout == layout) {
+      return h->second;
+    }
+  }
+  return 0;
+}
+
 void 
 LayoutHandle::get_names (std::vector <std::string> &names)
 {
@@ -484,6 +495,10 @@ LayoutHandleRef::operator= (const LayoutHandleRef &r)
 void
 LayoutHandleRef::set (LayoutHandle *h)
 {
+  if (mp_handle == h) {
+    return;
+  }
+
   if (mp_handle) {
     mp_handle->remove_ref ();
     mp_handle = 0;
diff --git a/src/laybasic/laybasic/layCellView.h b/src/laybasic/laybasic/layCellView.h
index 0f5bee9d9..7f350f691 100644
--- a/src/laybasic/laybasic/layCellView.h
+++ b/src/laybasic/laybasic/layCellView.h
@@ -144,6 +144,14 @@ public:
    */
   static LayoutHandle *find (const std::string &name);
 
+  /**
+   *  @brief Finds a handle by layout object
+   *
+   *  @param layout The Layout object bound to the handle
+   *  @return 0, if there is no layout object with this name. Otherwise a pointer to its handle
+   */
+  static LayoutHandle *find_layout (const db::Layout *layout);
+
   /**
    *  @brief Gets the names of all registered layout objects
    */
diff --git a/testdata/ruby/layLayoutView.rb b/testdata/ruby/layLayoutView.rb
index fdd384cc6..d2c29ea0b 100644
--- a/testdata/ruby/layLayoutView.rb
+++ b/testdata/ruby/layLayoutView.rb
@@ -550,6 +550,26 @@ class LAYLayoutView_TestClass < TestBase
 
   end
 
+  # issue-1533
+  def test_8
+
+    if !RBA.constants.member?(:Application)
+      return
+    end
+
+    app = RBA::Application.instance
+    mw = app.main_window
+    mw.close_all
+    mw.create_view
+
+    ly = RBA::Layout::new
+    mw.current_view.show_layout(ly, false)
+
+    # was crashing
+    mw.current_view.show_layout(ly, false)
+
+  end
+
 end
 
 load("test_epilogue.rb")