From 92e4460911d23dd6889e9c02333e93882912e82a Mon Sep 17 00:00:00 2001
From: Po Lu <luangruo@yahoo.com>
Date: Sun, 9 Jan 2022 01:28:22 +0000
Subject: [PATCH] Implement override redirect on Haiku

* src/haiku_support.cc (pre_override_redirect_style):
(pre_override_redirect_feel): New variables.
(BWindow_set_override_redirect):
* src/haiku_support.h (BWindow_set_override_redirect): New
functions.
* src/haikufns.c (haiku_create_frame): Set override redirect.
(haiku_set_override_redirect): New function.
(haiku_frame_parm_handlers): Add `haiku_set_override_redirect'
---
 src/haiku_support.cc | 30 ++++++++++++++++++++++++++++++
 src/haiku_support.h  |  3 +++
 src/haikufns.c       | 17 ++++++++++++++++-
 3 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/src/haiku_support.cc b/src/haiku_support.cc
index 2e9eff40676..47a6af92f61 100644
--- a/src/haiku_support.cc
+++ b/src/haiku_support.cc
@@ -62,6 +62,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include <kernel/scheduler.h>
 
 #include <private/interface/ToolTip.h>
+#include <private/interface/WindowPrivate.h>
 
 #include <cmath>
 #include <cstring>
@@ -271,6 +272,8 @@ public:
   int shown_flag = 0;
   volatile int was_shown_p = 0;
   bool menu_bar_active_p = false;
+  window_look pre_override_redirect_style;
+  window_feel pre_override_redirect_feel;
 
   EmacsWindow () : BWindow (BRect (0, 0, 0, 0), "", B_TITLED_WINDOW_LOOK,
 			    B_NORMAL_WINDOW_FEEL, B_NO_SERVER_SIDE_WINDOW_MODIFIERS)
@@ -3058,3 +3061,30 @@ be_use_subpixel_antialiasing (void)
 
   return current_subpixel_antialiasing;
 }
+
+/* This isn't implemented very properly (for example: what if
+   decorations are changed while the window is under override
+   redirect?) but it works well enough for most use cases.  */
+void
+BWindow_set_override_redirect (void *window, bool override_redirect_p)
+{
+  EmacsWindow *w = (EmacsWindow *) window;
+
+  if (w->LockLooper ())
+    {
+      if (override_redirect_p)
+	{
+	  w->pre_override_redirect_feel = w->Feel ();
+	  w->pre_override_redirect_style = w->Look ();
+	  w->SetFeel (kMenuWindowFeel);
+	  w->SetLook (B_NO_BORDER_WINDOW_LOOK);
+	}
+      else
+	{
+	  w->SetFeel (w->pre_override_redirect_feel);
+	  w->SetLook (w->pre_override_redirect_style);
+	}
+
+      w->UnlockLooper ();
+    }
+}
diff --git a/src/haiku_support.h b/src/haiku_support.h
index 6a99eb245dc..961d6d3a892 100644
--- a/src/haiku_support.h
+++ b/src/haiku_support.h
@@ -856,6 +856,9 @@ extern "C"
   extern bool
   be_use_subpixel_antialiasing (void);
 
+  extern void
+  BWindow_set_override_redirect (void *window, bool override_redirect_p);
+
 #ifdef __cplusplus
   extern void *
   find_appropriate_view_for_draw (void *vw);
diff --git a/src/haikufns.c b/src/haikufns.c
index 4a0d2272d08..52bb13bc89b 100644
--- a/src/haikufns.c
+++ b/src/haikufns.c
@@ -835,6 +835,7 @@ haiku_create_frame (Lisp_Object parms, int ttip_p)
     haiku_set_parent_frame (f, parent_frame, Qnil);
 
   gui_default_parameter (f, parms, Qundecorated, Qnil, NULL, NULL, RES_TYPE_BOOLEAN);
+  gui_default_parameter (f, parms, Qoverride_redirect, Qnil, NULL, NULL, RES_TYPE_BOOLEAN);
 
   gui_default_parameter (f, parms, Qicon_type, Qnil,
                          "bitmapIcon", "BitmapIcon", RES_TYPE_SYMBOL);
@@ -1067,6 +1068,20 @@ haiku_set_undecorated (struct frame *f, Lisp_Object new_value,
   unblock_input ();
 }
 
+static void
+haiku_set_override_redirect (struct frame *f, Lisp_Object new_value,
+			     Lisp_Object old_value)
+{
+  if (EQ (new_value, old_value))
+    return;
+
+  block_input ();
+  BWindow_set_override_redirect (FRAME_HAIKU_WINDOW (f),
+				 !NILP (new_value));
+  FRAME_OVERRIDE_REDIRECT (f) = !NILP (new_value);
+  unblock_input ();
+}
+
 static void
 haiku_set_menu_bar_lines (struct frame *f, Lisp_Object value, Lisp_Object oldval)
 {
@@ -2430,7 +2445,7 @@ frame_parm_handler haiku_frame_parm_handlers[] =
     haiku_set_no_focus_on_map,
     haiku_set_no_accept_focus,
     NULL, /* set z group */
-    NULL, /* set override redir */
+    haiku_set_override_redirect,
     gui_set_no_special_glyphs
   };
 
-- 
2.39.2