From b4090a7acddf951088b75fcce0d6edb721bbbf45 Mon Sep 17 00:00:00 2001
From: Jedidiah Barber <contact@jedbarber.id.au>
Date: Sun, 13 Oct 2024 03:33:38 +1300
Subject: Fixed bug with Text_Buffers not being deallocated correctly if
 declared after the Text_Display they are attached to

---
 src/c_fl_text_buffer.cpp                            | 21 +++++++++++++++++++--
 src/c_fl_text_buffer.h                              |  1 +
 ...tk-widgets-groups-text_displays-text_editors.adb |  1 +
 src/fltk-widgets-groups-text_displays.adb           |  6 ++++++
 src/fltk-widgets-groups-text_displays.ads           | 16 ++++++++++++++++
 5 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/src/c_fl_text_buffer.cpp b/src/c_fl_text_buffer.cpp
index 2df65f6..4a681e8 100644
--- a/src/c_fl_text_buffer.cpp
+++ b/src/c_fl_text_buffer.cpp
@@ -6,13 +6,30 @@
 
 
 
+class My_Text_Buffer : public Fl_Text_Buffer {
+    public:
+        using Fl_Text_Buffer::Fl_Text_Buffer;
+        int reference_count = 0;
+};
+
+
+
+
 TEXTBUFFER new_fl_text_buffer(int rs, int pgs) {
-    Fl_Text_Buffer *tb = new Fl_Text_Buffer(rs, pgs);
+    My_Text_Buffer *tb = new My_Text_Buffer(rs, pgs);
     return tb;
 }
 
+void upref_fl_text_buffer(TEXTBUFFER tb) {
+    reinterpret_cast<My_Text_Buffer*>(tb)->reference_count += 1;
+}
+
 void free_fl_text_buffer(TEXTBUFFER tb) {
-    delete reinterpret_cast<Fl_Text_Buffer*>(tb);
+    if (reinterpret_cast<My_Text_Buffer*>(tb)->reference_count <= 0) {
+        delete reinterpret_cast<My_Text_Buffer*>(tb);
+    } else {
+        reinterpret_cast<My_Text_Buffer*>(tb)->reference_count -= 1;
+    }
 }
 
 
diff --git a/src/c_fl_text_buffer.h b/src/c_fl_text_buffer.h
index 7258006..d808f44 100644
--- a/src/c_fl_text_buffer.h
+++ b/src/c_fl_text_buffer.h
@@ -12,6 +12,7 @@ typedef void* TEXTBUFFER;
 
 
 extern "C" TEXTBUFFER new_fl_text_buffer(int rs, int pgs);
+extern "C" void upref_fl_text_buffer(TEXTBUFFER tb);
 extern "C" void free_fl_text_buffer(TEXTBUFFER tb);
 
 
diff --git a/src/fltk-widgets-groups-text_displays-text_editors.adb b/src/fltk-widgets-groups-text_displays-text_editors.adb
index e0d4588..98175a6 100644
--- a/src/fltk-widgets-groups-text_displays-text_editors.adb
+++ b/src/fltk-widgets-groups-text_displays-text_editors.adb
@@ -388,6 +388,7 @@ package body FLTK.Widgets.Groups.Text_Displays.Text_Editors is
         then
             This.Clear;
             free_fl_text_editor (This.Void_Ptr);
+            free_fl_text_buffer (This.Raw_Buffer);
             This.Void_Ptr := Null_Pointer;
         end if;
         Finalize (Text_Display (This));
diff --git a/src/fltk-widgets-groups-text_displays.adb b/src/fltk-widgets-groups-text_displays.adb
index 59efc55..3dd9f6d 100644
--- a/src/fltk-widgets-groups-text_displays.adb
+++ b/src/fltk-widgets-groups-text_displays.adb
@@ -470,6 +470,7 @@ package body FLTK.Widgets.Groups.Text_Displays is
         then
             This.Clear;
             free_fl_text_display (This.Void_Ptr);
+            free_fl_text_buffer (This.Raw_Buffer);
             This.Void_Ptr := Null_Pointer;
         end if;
         Finalize (Group (This));
@@ -546,6 +547,11 @@ package body FLTK.Widgets.Groups.Text_Displays is
     begin
         This.Buffer := Buff'Unchecked_Access;
         fl_text_display_set_buffer (This.Void_Ptr, Wrapper (Buff).Void_Ptr);
+        if This.Raw_Buffer /= Null_Pointer then
+            free_fl_text_buffer (This.Raw_Buffer);
+        end if;
+        This.Raw_Buffer := Wrapper (Buff).Void_Ptr;
+        upref_fl_text_buffer (This.Raw_Buffer);
     end Set_Buffer;
 
 
diff --git a/src/fltk-widgets-groups-text_displays.ads b/src/fltk-widgets-groups-text_displays.ads
index 609561e..76cff42 100644
--- a/src/fltk-widgets-groups-text_displays.ads
+++ b/src/fltk-widgets-groups-text_displays.ads
@@ -359,6 +359,7 @@ private
     type Text_Display is new Group with
         record
             Buffer         : access FLTK.Text_Buffers.Text_Buffer;
+            Raw_Buffer     : Storage.Integer_Address := Null_Pointer;
             Style_Callback : Styles.Unfinished_Style_Callback;
         end record;
 
@@ -373,6 +374,21 @@ private
 
 
 
+    --  Adds some basic reference counting on the C side to help ensure any Text_Buffers
+    --  do not get deallocated before all Text_Displays they might be attached to.
+    procedure upref_fl_text_buffer
+           (TB : in Storage.Integer_Address);
+    pragma Import (C, upref_fl_text_buffer, "upref_fl_text_buffer");
+    pragma Inline (upref_fl_text_buffer);
+
+    procedure free_fl_text_buffer
+           (TB : in Storage.Integer_Address);
+    pragma Import (C, free_fl_text_buffer, "free_fl_text_buffer");
+    pragma Inline (free_fl_text_buffer);
+
+
+
+
     pragma Inline (Get_Buffer);
     pragma Inline (Set_Buffer);
 
-- 
cgit