[gtk/wip/chergert/quartz4u] macos: implement some GtkSettings getters

[Christian Hergert <chergert src gnome org>]

commit f2752afca534c07217d805342ecbf1cd37ac938e
Author: Christian Hergert <chergert redhat com>
Date:   Sat May 9 14:24:43 2020 -0700

    macos: implement some GtkSettings getters

 gdk/macos/gdkmacosdisplay-private.h  |  3 ++
 gdk/macos/gdkmacosdisplay-settings.c | 93 ++++++++++++++++++++++++++++++++++++
 gdk/macos/gdkmacosdisplay.c          |  2 +-
 gdk/macos/meson.build                |  1 +
 4 files changed, 98 insertions(+), 1 deletion(-)
---
diff --git a/gdk/macos/gdkmacosdisplay-private.h b/gdk/macos/gdkmacosdisplay-private.h
index 01c20ccfe2..3963a681f1 100644
--- a/gdk/macos/gdkmacosdisplay-private.h
+++ b/gdk/macos/gdkmacosdisplay-private.h
@@ -67,6 +67,9 @@ void             _gdk_macos_display_synthesize_motion              (GdkMacosDisp
 NSWindow        *_gdk_macos_display_find_native_under_pointer      (GdkMacosDisplay *self,
                                                                     int             *x,
                                                                     int             *y);
+gboolean         _gdk_macos_display_get_setting                    (GdkMacosDisplay *self,
+                                                                    const gchar     *setting,
+                                                                    GValue          *value);
 
 G_END_DECLS
 
diff --git a/gdk/macos/gdkmacosdisplay-settings.c b/gdk/macos/gdkmacosdisplay-settings.c
new file mode 100644
index 0000000000..cf552cce07
--- /dev/null
+++ b/gdk/macos/gdkmacosdisplay-settings.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright © 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
+ * Copyright © 1998-2002 Tor Lillqvist
+ * Copyright © 2005-2008 Imendio AB
+ * Copyright © 2020 Red Hat, 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 2.1 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. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "gdkmacosdisplay-private.h"
+#include "gdkmacosutils-private.h"
+
+gboolean
+_gdk_macos_display_get_setting (GdkMacosDisplay *self,
+                                const gchar     *setting,
+                                GValue          *value)
+{
+  GDK_BEGIN_MACOS_ALLOC_POOL;
+
+  gboolean ret = FALSE;
+
+  g_return_val_if_fail (GDK_IS_MACOS_DISPLAY (self), FALSE);
+  g_return_val_if_fail (setting != NULL, FALSE);
+  g_return_val_if_fail (value != NULL, FALSE);
+
+
+  if (FALSE) {}
+  else if (strcmp (setting, "gtk-double-click-time") == 0)
+    {
+      NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
+      float t = [defaults floatForKey:@"com.apple.mouse.doubleClickThreshold"];
+
+      /* No user setting, use the default in OS X. */
+      if (t == 0.0)
+        t = 0.5;
+
+      g_value_set_int (value, t * 1000);
+
+      ret = TRUE;
+    }
+  else if (strcmp (setting, "gtk-font-name") == 0)
+    {
+      NSString *name;
+      char *str;
+      gint size;
+
+      name = [[NSFont systemFontOfSize:0] familyName];
+      size = (gint)[[NSFont userFontOfSize:0] pointSize];
+
+      /* Let's try to use the "views" font size (12pt) by default. This is
+       * used for lists/text/other "content" which is the largest parts of
+       * apps, using the "regular control" size (13pt) looks a bit out of
+       * place. We might have to tweak this.
+       */
+
+      /* The size has to be hardcoded as there doesn't seem to be a way to
+       * get the views font size programmatically.
+       */
+      str = g_strdup_printf ("%s %d", [name UTF8String], size);
+      g_value_take_string (value, g_steal_pointer (&str));
+
+      ret = TRUE;
+    }
+  else if (strcmp (setting, "gtk-primary-button-warps-slider") == 0)
+    {
+      BOOL b = [[NSUserDefaults standardUserDefaults] boolForKey:@"AppleScrollerPagingBehavior"];
+      /* If the Apple property is YES, it means "warp" */
+      g_value_set_boolean (value, b == YES);
+      ret = TRUE;
+    }
+  else if (strcmp (setting, "gtk-shell-shows-desktop") == 0)
+    {
+      g_value_set_boolean (value, TRUE);
+      ret = TRUE;
+    }
+
+  GDK_END_MACOS_ALLOC_POOL;
+
+  return ret;
+}
diff --git a/gdk/macos/gdkmacosdisplay.c b/gdk/macos/gdkmacosdisplay.c
index 8646cca36b..955b507f84 100644
--- a/gdk/macos/gdkmacosdisplay.c
+++ b/gdk/macos/gdkmacosdisplay.c
@@ -104,7 +104,7 @@ gdk_macos_display_get_setting (GdkDisplay  *display,
                                const gchar *setting,
                                GValue      *value)
 {
-  return FALSE;
+  return _gdk_macos_display_get_setting (GDK_MACOS_DISPLAY (display), setting, value);
 }
 
 static int
diff --git a/gdk/macos/meson.build b/gdk/macos/meson.build
index 0ee0e11e1f..c10a3bb5b8 100644
--- a/gdk/macos/meson.build
+++ b/gdk/macos/meson.build
@@ -5,6 +5,7 @@ gdk_macos_sources = files([
   'gdkmacoscursor.c',
   'gdkmacosdevice.c',
   'gdkmacosdisplay.c',
+  'gdkmacosdisplay-settings.c',
   'gdkmacosdisplay-translate.c',
   'gdkmacosdragsurface.c',
   'gdkmacoseventsource.c',