wayland: add WaylandInputServer for input method support

ChangeLog

@@ -1,3 +1,17 @@
+2026-05-21 DMJC <jcarthew@gmail.com>
+
+	* Headers/wayland/WaylandInputServer.h:
+	* Source/wayland/WaylandInputServer.m:
+	* Source/wayland/GNUmakefile:
+	* Headers/wayland/WaylandServer.h:
+	* Source/wayland/WaylandServer.m:
+	Add WaylandInputServer, implementing the NSInputServer/NSInputServiceProvider
+	protocol for the Wayland backend.  WaylandServer instantiates it at startup
+	and delegates all input-method queries (inputMethodStyle, fontSize,
+	clientWindowRect, preedit/status area accessors) to it via a new
+	WaylandServer (InputMethod) category.  The focused window is tracked via
+	activeConversationChanged:.
+
 2026-05-21 DMJC <jcarthew@gmail.com>
 
 	* configure.ac:

Headers/wayland/WaylandInputServer.h

@@ -0,0 +1,54 @@
+/* WaylandInputServer - Keyboard input handling for Wayland backend
+
+   Copyright (C) 2024 Free Software Foundation, Inc.
+
+   This file is part of the GNUstep Backend.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; see the file COPYING.LIB.
+   If not, see <http://www.gnu.org/licenses/> or write to the
+   Free Software Foundation, 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+
+#ifndef _WaylandInputServer_h_INCLUDE
+#define _WaylandInputServer_h_INCLUDE
+
+#include <AppKit/NSInputServer.h>
+
+@interface WaylandInputServer : NSInputServer
+{
+  id        delegate;
+  NSString *server_name;
+  int       focused_window_id;
+}
+
+- (id) initWithDelegate: (id)aDelegate name: (NSString *)name;
+- (void) setFocusedWindowId: (int)windowId;
+- (int) focusedWindowId;
+
+@end
+
+@interface WaylandInputServer (InputMethod)
+- (NSString *) inputMethodStyle;
+- (NSString *) fontSize: (int *)size;
+- (BOOL) clientWindowRect: (NSRect *)rect;
+- (BOOL) statusArea: (NSRect *)rect;
+- (BOOL) preeditArea: (NSRect *)rect;
+- (BOOL) preeditSpot: (NSPoint *)p;
+- (BOOL) setStatusArea: (NSRect *)rect;
+- (BOOL) setPreeditArea: (NSRect *)rect;
+- (BOOL) setPreeditSpot: (NSPoint *)p;
+@end
+
+#endif /* _WaylandInputServer_h_INCLUDE */

Headers/wayland/WaylandServer.h

@@ -189,12 +189,24 @@ struct window *get_window_with_id(WaylandConfig *wlconfig, int winid);
   WaylandConfig *wlconfig;
 
   BOOL _mouseInitialized;
+  id   inputServer;
 }
 @end
 
-@interface
-WaylandServer (Cursor)
-- (void)initializeMouseIfRequired;
+@interface WaylandServer (Cursor)
+- (void) initializeMouseIfRequired;
+@end
+
+@interface WaylandServer (InputMethod)
+- (NSString *) inputMethodStyle;
+- (NSString *) fontSize: (int *)size;
+- (BOOL) clientWindowRect: (NSRect *)rect;
+- (BOOL) statusArea: (NSRect *)rect;
+- (BOOL) preeditArea: (NSRect *)rect;
+- (BOOL) preeditSpot: (NSPoint *)p;
+- (BOOL) setStatusArea: (NSRect *)rect;
+- (BOOL) setPreeditArea: (NSRect *)rect;
+- (BOOL) setPreeditSpot: (NSPoint *)p;
 @end
 
 #endif /* _WaylandServer_h_INCLUDE */

Source/wayland/GNUmakefile

@@ -51,6 +51,7 @@ WaylandServer+Keyboard.m  \
 WaylandServer+Seat.m  \
 WaylandServer+Xdgshell.m  \
 WaylandServer+Layershell.m  \
+WaylandInputServer.m  \
 
 ifeq ($(WITH_EGL),yes)
 wayland_OBJC_FILES += \

Source/wayland/WaylandInputServer.m

@@ -0,0 +1,155 @@
+/* WaylandInputServer - Keyboard input handling for Wayland backend
+
+   Copyright (C) 2024 Free Software Foundation, Inc.
+
+   This file is part of the GNUstep Backend.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; see the file COPYING.LIB.
+   If not, see <http://www.gnu.org/licenses/> or write to the
+   Free Software Foundation, 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.
+*/
+
+#include "config.h"
+
+#include <Foundation/NSUserDefaults.h>
+#include <Foundation/NSDebug.h>
+#include <Foundation/NSException.h>
+#include <AppKit/NSApplication.h>
+#include <AppKit/NSGraphics.h>
+#include <AppKit/NSWindow.h>
+#include <GNUstepGUI/GSDisplayServer.h>
+
+#include "wayland/WaylandInputServer.h"
+
+@implementation WaylandInputServer
+
+- (id) initWithDelegate: (id)aDelegate name: (NSString *)name
+{
+  delegate = aDelegate;
+  ASSIGN(server_name, name);
+  focused_window_id = 0;
+  NSDebugLog(@"WaylandInputServer: initialized");
+  return self;
+}
+
+- (void) dealloc
+{
+  DESTROY(server_name);
+  [super dealloc];
+}
+
+- (void) setFocusedWindowId: (int)windowId
+{
+  focused_window_id = windowId;
+  NSDebugLog(@"WaylandInputServer: focused window id = %d", windowId);
+}
+
+- (int) focusedWindowId
+{
+  return focused_window_id;
+}
+
+/* NSInputServiceProvider protocol */
+
+- (void) activeConversationChanged: (id)sender
+             toNewConversation: (long)newConversation
+{
+  [super activeConversationChanged: sender toNewConversation: newConversation];
+
+  if ([sender respondsToSelector: @selector(window)] == NO)
+    return;
+
+  /* sender is a text client; -window is checked via respondsToSelector above */
+  NSWindow *window = [sender performSelector: @selector(window)];
+  if (window != nil)
+    {
+      focused_window_id = [window windowNumber];
+      NSDebugLog(@"WaylandInputServer: conversation changed, focused window = %d",
+		 focused_window_id);
+    }
+}
+
+- (void) activeConversationWillChange: (id)sender
+             fromOldConversation: (long)oldConversation
+{
+  [super activeConversationWillChange: sender
+		 fromOldConversation: oldConversation];
+}
+
+@end
+
+@implementation WaylandInputServer (InputMethod)
+
+- (NSString *) inputMethodStyle
+{
+  /* Wayland keyboard input is handled directly via XKB in WaylandServer+Keyboard.m.
+     No input method overlay is used. */
+  return nil;
+}
+
+- (NSString *) fontSize: (int *)size
+{
+  NSString *str;
+
+  str = [[NSUserDefaults standardUserDefaults] stringForKey: @"NSFontSize"];
+  if (!str)
+    str = @"12";
+  if (size)
+    *size = (int) strtol([str cString], NULL, 10);
+  return str;
+}
+
+- (BOOL) clientWindowRect: (NSRect *)rect
+{
+  if (!rect || focused_window_id == 0)
+    return NO;
+  NSWindow *window = GSWindowWithNumber(focused_window_id);
+  if (window == nil)
+    return NO;
+  *rect = [window frame];
+  return YES;
+}
+
+- (BOOL) statusArea: (NSRect *)rect
+{
+  return NO;
+}
+
+- (BOOL) preeditArea: (NSRect *)rect
+{
+  return NO;
+}
+
+- (BOOL) preeditSpot: (NSPoint *)p
+{
+  return NO;
+}
+
+- (BOOL) setStatusArea: (NSRect *)rect
+{
+  return NO;
+}
+
+- (BOOL) setPreeditArea: (NSRect *)rect
+{
+  return NO;
+}
+
+- (BOOL) setPreeditSpot: (NSPoint *)p
+{
+  return NO;
+}
+
+@end

Source/wayland/WaylandServer.m

@@ -46,6 +46,7 @@
 #include <sys/mman.h>
 
 #include "wayland/WaylandServer.h"
+#include "wayland/WaylandInputServer.h"
 #ifdef HAVE_EGL
 #include "wayland/WaylandOpenGL.h"
 #endif
@@ -228,6 +229,9 @@ - (id)_initWaylandContext
 	       @"compositor must support the stable XDG Shell protocol"];
     }
 
+  inputServer = [[WaylandInputServer allocWithZone: [self zone]]
+		   initWithDelegate: nil name: @"WaylandInput"];
+
   return self;
 }
 
@@ -275,6 +279,7 @@ - (id)initWithAttributes:(NSDictionary *)info
 - (void)dealloc
 {
   NSDebugLog(@"Destroying Wayland Server");
+  DESTROY(inputServer);
   [super dealloc];
 }
 
@@ -368,6 +373,64 @@ - (void)beep
 
 @end
 
+@implementation WaylandServer (InputMethod)
+
+- (NSString *) inputMethodStyle
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer inputMethodStyle] : nil;
+}
+
+- (NSString *) fontSize: (int *)size
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer fontSize: size] : nil;
+}
+
+- (BOOL) clientWindowRect: (NSRect *)rect
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer clientWindowRect: rect] : NO;
+}
+
+- (BOOL) statusArea: (NSRect *)rect
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer statusArea: rect] : NO;
+}
+
+- (BOOL) preeditArea: (NSRect *)rect
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer preeditArea: rect] : NO;
+}
+
+- (BOOL) preeditSpot: (NSPoint *)p
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer preeditSpot: p] : NO;
+}
+
+- (BOOL) setStatusArea: (NSRect *)rect
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer setStatusArea: rect] : NO;
+}
+
+- (BOOL) setPreeditArea: (NSRect *)rect
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer setPreeditArea: rect] : NO;
+}
+
+- (BOOL) setPreeditSpot: (NSPoint *)p
+{
+  return inputServer
+    ? [(WaylandInputServer *) inputServer setPreeditSpot: p] : NO;
+}
+
+@end
+
 @implementation
 WaylandServer (WindowOps)