Merge pull request The-OpenROAD-Project#8720 from hongted/gui-singleton

gui: Updated singleton pattern for gui::Gui::get().

Author: maliberty

src/gpl/src/MakeReplace.cpp

@@ -5,6 +5,8 @@
 
 #include "gpl/Replace.h"
 #include "graphicsImpl.h"
+#include "graphicsNone.h"
+#include "gui/gui.h"
 #include "tcl.h"
 #include "utl/Logger.h"
 #include "utl/decode.h"
@@ -25,7 +27,11 @@ void initReplace(Tcl_Interp* tcl_interp)
 
 void initReplaceGraphics(Replace* replace, utl::Logger* log)
 {
-  replace->setGraphicsInterface(gpl::GraphicsImpl(log));
+  if (gui::Gui::get() == nullptr) {
+    replace->setGraphicsInterface(gpl::GraphicsNone());
+  } else {
+    replace->setGraphicsInterface(gpl::GraphicsImpl(log));
+  }
 }
 
 }  // namespace gpl

src/gui/include/gui/gui.h

@@ -950,8 +950,6 @@ class Gui
   std::unique_ptr<GIF> gif_;
   static constexpr int kDefaultGifDelay = 250;
 
-  static Gui* singleton_;
-
   std::string main_window_title_ = "OpenROAD";
 };
 

src/gui/src/gui.cpp

@@ -208,15 +208,11 @@ static void resetConversions()
       = [](const std::string& value, bool*) { return 0; };
 }
 
-Gui* Gui::singleton_ = nullptr;
-
 Gui* Gui::get()
 {
-  if (singleton_ == nullptr) {
-    singleton_ = new Gui();
-  }
+  static Gui* singleton = new Gui();
 
-  return singleton_;
+  return singleton;
 }
 
 Gui::Gui()

src/gui/src/stub.cpp

@@ -24,8 +24,6 @@ struct GifWriter
 
 namespace gui {
 
-Gui* Gui::singleton_ = nullptr;
-
 // Used by toString to convert dbu to microns
 DBUToString Descriptor::Property::convert_dbu
     = [](int value, bool) { return std::to_string(value); };
@@ -54,7 +52,7 @@ Gui::Gui() : continue_after_close_(false), logger_(nullptr), db_(nullptr)
 
 Gui* gui::Gui::get()
 {
-  return singleton_;
+  return nullptr;
 }
 
 bool gui::Gui::enabled()