Merge pull request #42 from qmfrederik/features/headless-pr

Add headless backend

.github/workflows/main.yml

@@ -14,6 +14,16 @@ jobs:
     # don't run pull requests from local branches twice
     if: github.event_name != 'pull_request' || github.event.pull_request.head.repo.full_name != github.repository
 
+    strategy:
+      matrix:
+        include:
+          - server: x11
+            graphics: cairo
+          - server: x11
+            graphics: xlib
+          - server: headless
+            graphics: headless
+
     env:
       DEBIAN_FRONTEND: noninteractive
 
@@ -28,7 +38,7 @@ jobs:
       - name: Build source
         run: |
           . /usr/share/GNUstep/Makefiles/GNUstep.sh
-          ./configure
+          ./configure --enable-server=${{ matrix.server }} --enable-graphics=${{ matrix.graphics }}
           make && make install
 
       - name: Run tests

Headers/headless/HeadlessContext.h

@@ -0,0 +1,33 @@
+/*
+   HeadlessContext.h
+
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+   This file is part of GNUstep.
+
+   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 HeadlessContext_h
+#define HeadlessContext_h
+
+#include "gsc/GSContext.h"
+
+@interface HeadlessContext : GSContext
+@end
+
+#endif /* HeadlessContext_h */

Headers/headless/HeadlessFaceInfo.h

@@ -0,0 +1,42 @@
+/*
+   HeadlessFaceInfo.h
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+   Based on work by: Alexander Malmberg <alexander@malmberg.org>
+   Based on work by: Fred Kiefer <fredkiefer@gmx.de>
+
+   This file is part of GNUstep.
+
+   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 HeadlessFaceInfo_h
+#define HeadlessFaceInfo_h
+
+#include <Foundation/NSObject.h>
+
+@interface HeadlessFaceInfo : NSObject
+{
+	void *_fontFace;
+}
+
+- (void *)fontFace;
+
+@end
+#endif /* HeadlessFaceInfo_h */

Headers/headless/HeadlessFontEnumerator.h

@@ -0,0 +1,41 @@
+/*
+   HeadlessFontEnumeartorInfo.h
+
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+
+   This file is part of GNUstep.
+
+   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 HeadlessFontEnumerator_h
+#define HeadlessFontEnumerator_h
+
+#include <GNUstepGUI/GSFontInfo.h>
+
+#include "headless/HeadlessFaceInfo.h"
+
+@interface HeadlessFontEnumerator : GSFontEnumerator
+{
+}
++ (Class) faceInfoClass;
++ (HeadlessFaceInfo *) fontWithName: (NSString *)name;
+@end
+
+#endif /* HeadlessFontEnumerator_h */

Headers/headless/HeadlessFontInfo.h

@@ -0,0 +1,35 @@
+/*
+   HeadlessFontInfo.h
+
+   Copyright (C) 2003 Free Software Foundation, Inc.
+
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+
+   This file is part of GNUstep.
+
+   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 HeadlessFontInfo_h
+#define HeadlessFontInfo_h
+
+#include <GNUstepGUI/GSFontInfo.h>
+
+@interface HeadlessFontInfo : GSFontInfo
+@end
+
+#endif /* HeadlessFontInfo_h */

Headers/headless/HeadlessGState.h

@@ -0,0 +1,37 @@
+/*
+   HeadlessGState.h
+
+   Copyright (C) 2004 Free Software Foundation, Inc.
+
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+
+   This file is part of GNUstep.
+
+   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 HeadlessGState_h
+#define HeadlessGState_h
+
+#include "gsc/GSGState.h"
+
+@interface HeadlessGState : GSGState
+{
+}
+@end
+
+#endif /* HeadlessGState_h */

Headers/headless/HeadlessServer.h

@@ -0,0 +1,37 @@
+/*
+   HeadlessServer.h
+
+   Copyright (C) 2002-2015 Free Software Foundation, Inc.
+
+   This file is part of GNUstep.
+
+   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 HeadlessServer_h
+#define HeadlessServer_h
+
+#include "config.h"
+
+#include <GNUstepGUI/GSDisplayServer.h>
+
+@interface HeadlessServer : GSDisplayServer
+{
+}
+@end
+
+#endif /* HeadlessServer_h */

Source/GNUmakefile

@@ -43,7 +43,7 @@ endif
 #
 # The list of subproject directories
 #
-SUBPROJECTS = gsc $(BUILD_SERVER) $(BUILD_GRAPHICS)
+SUBPROJECTS = $(sort gsc $(BUILD_SERVER) $(BUILD_GRAPHICS))
 
 libgnustep-$(BACKEND_FULL)_SUBPROJECTS=$(SUBPROJECTS)
 

Source/GSBackend.m

@@ -50,6 +50,11 @@
 @interface WaylandServer (Initialize)
 + (void) initializeBackend;
 @end
+#elif BUILD_SERVER == SERVER_headless
+#include <headless/HeadlessServer.h>
+@interface HeadlessServer (Initialize)
++ (void) initializeBackend;
+@end
 #endif
 
 /* Call the correct initalization routines for the choosen
@@ -70,6 +75,8 @@
   [WIN32Server initializeBackend];
 #elif BUILD_SERVER == SERVER_wayland
   [WaylandServer initializeBackend];
+#elif BUILD_SERVER == SERVER_headless
+  [HeadlessServer initializeBackend];
 #else
   [NSException raise: NSInternalInconsistencyException
 	       format: @"No Window Server configured in backend"];
@@ -96,6 +103,8 @@
     context = @"CairoContext";
 #elif (BUILD_GRAPHICS==GRAPHICS_opal)
     context = @"OpalContext";
+#elif (BUILD_GRAPHICS==GRAPHICS_headless)
+    context = @"HeadlessContext";    
 #else
 #error INVALID build graphics type
 #endif

Source/headless/GNUmakefile

@@ -0,0 +1,48 @@
+#
+#  Main makefile for GNUstep Headless Backend
+#
+#  Copyright (C) 2002 Free Software Foundation, Inc.
+#
+#  Author: Adam Fedor <fedor@gnu.org>
+#
+#  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, 
+
+PACKAGE_NAME = gnustep-back
+GNUSTEP_LOCAL_ADDITIONAL_MAKEFILES=../../back.make
+
+include $(GNUSTEP_MAKEFILES)/common.make
+
+include ../../config.make
+
+# The library to be compiled, as a library or as a bundle
+SUBPROJECT_NAME=headless
+
+# The Objective-C source files to be compiled
+headless_OBJC_FILES = \
+HeadlessContext.m \
+HeadlessServer.m \
+HeadlessFontInfo.m \
+HeadlessFontEnumerator.m \
+HeadlessFaceInfo.m \
+HeadlessGState.m
+
+-include GNUmakefile.preamble
+
+include $(GNUSTEP_MAKEFILES)/subproject.make
+
+-include GNUmakefile.postamble

Source/headless/GNUmakefile.preamble

@@ -0,0 +1,51 @@
+#
+#  GNUmakefile.preamble
+#
+#  Copyright (C) 2002 Free Software Foundation, Inc.
+#
+#  Author: Adam Fedor <fedor@gnu.org>
+#
+#  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.
+
+#
+# Flags dealing with compiling and linking
+#
+
+# Additional flags to pass to the preprocessor
+ADDITIONAL_CPPFLAGS += -Wall $(CONFIG_SYSTEM_DEFS)
+
+# Additional flags to pass to the Objective-C compiler
+ADDITIONAL_OBJCFLAGS = 
+
+# Additional flags to pass to the C compiler
+ADDITIONAL_CFLAGS = 
+
+# Additional include directories the compiler should search
+ADDITIONAL_INCLUDE_DIRS += -I../../Headers \
+	-I../$(GNUSTEP_TARGET_DIR) $(GRAPHIC_CFLAGS)
+
+# Additional LDFLAGS to pass to the linker
+ADDITIONAL_LDFLAGS =
+
+# Additional library directories the linker should search
+ADDITIONAL_LIB_DIRS =
+
+#
+# Flags dealing with installing and uninstalling
+#

Source/headless/HeadlessContext.m

@@ -0,0 +1,45 @@
+/*
+   HeadlessContext.m
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   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 "headless/HeadlessContext.h"
+#include "headless/HeadlessFontInfo.h"
+#include "headless/HeadlessFontEnumerator.h"
+#include "headless/HeadlessGState.h"
+
+@implementation HeadlessContext
+
++ (void) initializeBackend
+{
+  [NSGraphicsContext setDefaultContextClass: self];
+
+  [GSFontEnumerator setDefaultClass: [HeadlessFontEnumerator class]];
+  [GSFontInfo setDefaultClass: [HeadlessFontInfo class]];
+}
+
++ (Class) GStateClass
+{
+  return [HeadlessGState class];
+}
+
+@end

Source/headless/HeadlessFaceInfo.m

@@ -0,0 +1,44 @@
+/*
+   HeadlessFaceInfo.m
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   Based on work by: Marcian Lytwyn <gnustep@advcsi.com> for Keysight
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+   Based on work by: Alex Malmberg
+   Based on work by: Fred Kiefer <fredkiefer@gmx.de>
+
+   This file is part of GNUstep.
+
+   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 "headless/HeadlessFaceInfo.h"
+
+@implementation HeadlessFaceInfo
+
+- (void) dealloc
+{
+  [super dealloc];
+}
+
+- (void *)fontFace
+{
+  return _fontFace;
+}
+
+@end

Source/headless/HeadlessFontEnumerator.m

@@ -0,0 +1,47 @@
+/*
+   HeadlessFontEnumerator.m
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   Based on work by: Marcian Lytwyn <gnustep@advcsi.com> for Keysight
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+   Based on work by: Alex Malmberg
+   Based on work by: Fred Kiefer <fredkiefer@gmx.de>
+
+   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 "headless/HeadlessFontEnumerator.h"
+#include "headless/HeadlessFontInfo.h"
+
+@implementation HeadlessFontEnumerator
+
++ (Class) faceInfoClass
+{
+  return [HeadlessFaceInfo class];
+}
+
++ (HeadlessFaceInfo *) fontWithName: (NSString *) name
+{
+  return (HeadlessFaceInfo *) [super fontWithName: name];
+}
+
+- (void)enumerateFontsAndFamilies
+{
+}
+
+@end

Source/headless/HeadlessFontInfo.m

@@ -0,0 +1,87 @@
+/*
+   HeadlessFontInfo.m
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   Based on work by: Marcian Lytwyn <gnustep@advcsi.com> for Keysight
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+   Based on work by: Alex Malmberg
+
+   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 "GNUstepBase/Unicode.h"
+#include <AppKit/NSAffineTransform.h>
+#include <AppKit/NSBezierPath.h>
+#include "headless/HeadlessFontInfo.h"
+#include "headless/HeadlessFontEnumerator.h"
+
+#include <math.h>
+
+@implementation HeadlessFontInfo
+
+- (id) initWithFontName: (NSString *)name
+		 matrix: (const CGFloat *)fmatrix
+	     screenFont: (BOOL)p_screenFont
+{
+  self = [super init];
+  if (!self)
+    return nil;
+
+#ifndef _MSC_VER
+  // Accessing instance variables across module boundaries is not supported by the Visual Studio
+  // toolchain; this could be implemented using e.g. setFontName: and setMatrix: method on the
+  // base case. 
+  fontName = [name copy];
+  memcpy(matrix, fmatrix, sizeof(matrix));
+#endif
+
+  return self;
+}
+
+- (void) dealloc
+{
+  [super dealloc];
+}
+
+- (BOOL) glyphIsEncoded: (NSGlyph)glyph
+{
+  return NO;
+}
+
+- (NSSize) advancementForGlyph: (NSGlyph)glyph
+{
+  return NSZeroSize;
+}
+
+- (NSRect) boundingRectForGlyph: (NSGlyph)glyph
+{
+  return NSZeroRect;
+}
+
+- (CGFloat) widthOfString: (NSString *)string
+{
+  return 0.0;
+}
+
+- (void) appendBezierPathWithGlyphs: (NSGlyph *)glyphs
+			      count: (int)length
+		       toBezierPath: (NSBezierPath *)path
+{
+}
+
+@end

Source/headless/HeadlessGState.m

@@ -0,0 +1,72 @@
+/*
+   HeadlessGState.m
+
+   Copyright (C) 2003, 2023 Free Software Foundation, Inc.
+
+   Based on work by: Marcian Lytwyn <gnustep@advcsi.com> for Keysight
+   Based on work by: Banlu Kemiyatorn <object at gmail dot com>
+   Based on work by: Fred Kiefer <fredkiefer@gmx.de>
+
+   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 "headless/HeadlessGState.h"
+
+@implementation HeadlessGState
+
+- (void) DPSclip
+{
+}
+
+- (void) DPSfill
+{
+}
+
+- (void) DPSsetlinewidth: (CGFloat)width
+{
+}
+
+- (void) DPSsetdash: (const CGFloat *)pat : (NSInteger)size : (CGFloat)foffset
+{
+}
+
+- (void) DPSimage: (NSAffineTransform *)matrix : (NSInteger)pixelsWide
+		 : (NSInteger)pixelsHigh : (NSInteger)bitsPerSample
+		 : (NSInteger)samplesPerPixel : (NSInteger)bitsPerPixel
+		 : (NSInteger)bytesPerRow : (BOOL)isPlanar
+		 : (BOOL)hasAlpha : (NSString *)colorSpaceName
+		 : (const unsigned char *const[5])data
+{
+}
+
+- (void) DPSstroke
+{
+}
+
+- (void) compositerect: (NSRect)aRect op: (NSCompositingOperation)op
+{
+}
+
+- (void) compositeGState: (HeadlessGState *)source
+		fromRect: (NSRect)srcRect
+		 toPoint: (NSPoint)destPoint
+		      op: (NSCompositingOperation)op
+		fraction: (CGFloat)delta
+{
+}
+
+@end

Source/headless/HeadlessServer.m

@@ -0,0 +1,115 @@
+/*
+   HeadlessServer.m
+
+   Copyright (C) 1998,2002,2023 Free Software Foundation, Inc.
+
+   Based on work by: Marcian Lytwyn <gnustep@advcsi.com> for Keysight
+   Based on work by: Adam Fedor <fedor@gnu.org>
+
+   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 <AppKit/NSApplication.h>
+#include <Foundation/NSDebug.h>
+#include <Foundation/NSValue.h>
+
+#include "headless/HeadlessServer.h"
+
+/* Terminate cleanly if we get a signal to do so */
+static void
+terminate(int sig)
+{
+  if (nil != NSApp)
+    {
+      [NSApp terminate: NSApp];
+    }
+  else
+    {
+      exit(1);
+    }
+}
+
+@implementation HeadlessServer
+
+/* Initialize AppKit backend */
++ (void) initializeBackend
+{
+  NSDebugLog(@"Initializing GNUstep headless backend.\n");
+  [GSDisplayServer setDefaultServerClass: [HeadlessServer class]];
+  signal(SIGTERM, terminate);
+  signal(SIGINT, terminate);
+}
+
+- (NSArray *)screenList
+{
+  NSDebugLog(@"GNUstep headless - fetching screen list");
+  NSMutableArray *screens = [NSMutableArray arrayWithCapacity: 1];
+  [screens addObject: [NSNumber numberWithInt: 1]];
+
+  return screens;
+}
+
+- (NSRect) boundsForScreen: (int)screen
+{
+ return NSMakeRect(0, 0, 400, 400);
+}
+
+- (NSWindowDepth) windowDepthForScreen: (int) screen_num
+{
+  return 0;
+}
+
+- (void) styleoffsets: (float *) l : (float *) r : (float *) t : (float *) b
+		     : (unsigned int) style
+{
+}
+
+- (void) standardcursor: (int)style : (void **)cid
+{
+}
+
+
+- (int) window: (NSRect)frame
+		    : (NSBackingStoreType)type
+		    : (unsigned int)style
+		    : (int)screen
+{
+    return 1;
+}
+
+- (void) setwindowlevel: (int)level : (int)win
+{
+}
+
+- (void) setWindowdevice: (int)win forContext: (NSGraphicsContext *)ctxt
+{
+}
+
+- (void) orderwindow: (int)op : (int)otherWin : (int)winNum
+{
+}
+
+- (void) setinputfocus: (int)win
+{
+}
+
+- (void) imagecursor: (NSPoint)hotp : (NSImage *)image : (void **)cid
+{
+}
+@end

config.h.in

@@ -1,15 +1,17 @@
 /* config.h.in.  Generated from configure.ac by autoheader.  */
 
 
-#define SERVER_x11      1
-#define SERVER_win32    2
-#define SERVER_wayland  3
-#define GRAPHICS_xdps   0
-#define GRAPHICS_art    1
-#define GRAPHICS_xlib   2
-#define GRAPHICS_winlib 3
-#define GRAPHICS_cairo  4
-#define GRAPHICS_opal   5
+#define SERVER_x11        1
+#define SERVER_win32      2
+#define SERVER_wayland    3
+#define SERVER_headless   4
+#define GRAPHICS_xdps     0
+#define GRAPHICS_art      1
+#define GRAPHICS_xlib     2
+#define GRAPHICS_winlib   3
+#define GRAPHICS_cairo    4
+#define GRAPHICS_opal     5
+#define GRAPHICS_headless 6
 
 
 /* Define to type of graphics context to build */
@@ -42,27 +44,33 @@
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
 
+/* Define to 1 if you have the `wayland-client' library (-lwayland-client). */
+#undef HAVE_LIBWAYLAND_CLIENT
+
 /* Define to 1 if you have the `Xext' library (-lXext). */
 #undef HAVE_LIBXEXT
 
 /* Define to 1 if you have the `Xft' library (-lXft). */
 #undef HAVE_LIBXFT
 
+/* Define to 1 if you have the `xkbcommon' library (-lxkbcommon). */
+#undef HAVE_LIBXKBCOMMON
+
 /* Define to 1 if you have the `Xmu' library (-lXmu). */
 #undef HAVE_LIBXMU
 
 /* Define to 1 if you have the `Xt' library (-lXt). */
 #undef HAVE_LIBXT
 
-/* Define to 1 if you have the <memory.h> header file. */
-#undef HAVE_MEMORY_H
-
 /* Define to 1 if you have the `shmctl' function. */
 #undef HAVE_SHMCTL
 
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 
+/* Define to 1 if you have the <stdio.h> header file. */
+#undef HAVE_STDIO_H
+
 /* Define to 1 if you have the <stdlib.h> header file. */
 #undef HAVE_STDLIB_H
 
@@ -93,6 +101,9 @@
 /* Define if you have XftDrawStringUtf8 */
 #undef HAVE_UTF8
 
+/* Define to 1 if you have the <wayland-util.h> header file. */
+#undef HAVE_WAYLAND_UTIL_H
+
 /* Define if you have the wgl library */
 #undef HAVE_WGL
 
@@ -102,6 +113,9 @@
 /* Define to 1 if you have the <X11/extensions/sync.h> header file. */
 #undef HAVE_X11_EXTENSIONS_SYNC_H
 
+/* Define to 1 if you have the <X11/extensions/Xrandr.h> header file. */
+#undef HAVE_X11_EXTENSIONS_XRANDR_H
+
 /* Define to 1 if you have the <X11/extensions/XShm.h> header file. */
 #undef HAVE_X11_EXTENSIONS_XSHM_H
 
@@ -118,15 +132,18 @@
 /* Define to 1 if you have 'XInternAtoms' function. */
 #undef HAVE_XINTERNATOMS
 
+/* Define to 1 if you have the <xkbcommon/xkbcommon.h> header file. */
+#undef HAVE_XKBCOMMON_XKBCOMMON_H
+
+/* Define to enable Xrandr support */
+#undef HAVE_XRANDR
+
 /* Define to enable Xshape support */
 #undef HAVE_XSHAPE
 
 /* Define to 1 if you have the `Xutf8LookupString' function. */
 #undef HAVE_XUTF8LOOKUPSTRING
 
-/* Define to enable Xrandr support */
-#undef HAVE_XRANDR
-
 /* Define to the address where bug reports for this package should be sent. */
 #undef PACKAGE_BUGREPORT
 
@@ -145,7 +162,9 @@
 /* Define to the version of this package. */
 #undef PACKAGE_VERSION
 
-/* Define to 1 if you have the ANSI C header files. */
+/* Define to 1 if all of the C90 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
 #undef STDC_HEADERS
 
 /* Define to enable glitz support */

configure.ac

@@ -565,10 +565,10 @@ case $target_os in
 esac
 
 AC_ARG_ENABLE(server, 
-  [  --enable-server=SRV     Build server type: x11, win32, wayland],,
+  [  --enable-server=SRV     Build server type: x11, win32, wayland, headless],,
   enable_server=$BUILD_SERVER)
 AC_ARG_ENABLE(graphics, 
-  [  --enable-graphics=GPH   Build graphics: xlib, xdps, winlib, art, cairo, opal],,
+  [  --enable-graphics=GPH   Build graphics: xlib, xdps, winlib, art, cairo, opal, headless],,
   enable_graphics="$BUILD_GRAPHICS")
 
 BUILD_SERVER=$enable_server
@@ -658,8 +658,6 @@ if test x"$BUILD_GRAPHICS" = "xcairo"; then
       CAIRO_LIBS="$CAIRO_LIBS $XFT_LIBS"
       CAIRO_CFLAGS="$CAIRO_CFLAGS"
       LIBS="-lwayland-client -lwayland-cursor -lxkbcommon $LIBS"
-    else
-      AC_MSG_ERROR([Invalid Cairo installation])
     fi
     LIBS="$CAIRO_LIBS $LIBS"
     CPPFLAGS="$CAIRO_CFLAGS $CPPFLAGS"
@@ -717,6 +715,8 @@ elif test x"$BUILD_GRAPHICS" = "xopal"; then
     fi
     AC_MSG_NOTICE([Switching to $BUILD_GRAPHICS])
   fi
+elif test x"$BUILD_GRAPHICS" = "xheadless"; then
+ : # Nothing to do
 else
   AC_MSG_ERROR([Invalid graphics backend $BUILD_GRAPHICS])
 fi
@@ -757,15 +757,17 @@ if test $BUILD_SERVER = win32; then
 fi
 
 AH_TOP([
-#define SERVER_x11      1
-#define SERVER_win32    2
-#define SERVER_wayland  3
-#define GRAPHICS_xdps   0
-#define GRAPHICS_art    1
-#define GRAPHICS_xlib   2
-#define GRAPHICS_winlib 3
-#define GRAPHICS_cairo  4
-#define GRAPHICS_opal   5
+#define SERVER_x11        1
+#define SERVER_win32      2
+#define SERVER_wayland    3
+#define SERVER_headless   4
+#define GRAPHICS_xdps     0
+#define GRAPHICS_art      1
+#define GRAPHICS_xlib     2
+#define GRAPHICS_winlib   3
+#define GRAPHICS_cairo    4
+#define GRAPHICS_opal     5
+#define GRAPHICS_headless 6
 ])
 AC_DEFINE_UNQUOTED(BUILD_SERVER,SERVER_$BUILD_SERVER,
 	[Define to type of window server to build])