From 6ca449672d3ce25b5b705c1a7a6168d7984a2762 Mon Sep 17 00:00:00 2001
From: Allison Lortie <desrt@desrt.ca>
Date: Wed, 2 Aug 2017 11:08:17 +0100
Subject: [PATCH] gsettingsschema: Allow per-desktop overrides
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Recognise a new 'd' option in schema keys which gives a dictionary of
per-desktop default values. This dictionary is searched for the items
found in XDG_CURRENT_DESKTOP, in the order. If nothing matches (or if
the option is missing) then the default value is used as before.

This feature was requested by Alberts Muktupāvels and this patch is
based on an approach devised by them.

https://bugzilla.gnome.org/show_bug.cgi?id=746592
---
 gio/gsettings.c                | 21 +++++++++++++++++
 gio/gsettingsschema-internal.h |  2 ++
 gio/gsettingsschema.c          | 41 ++++++++++++++++++++++++++++++++++
 3 files changed, 64 insertions(+)

diff --git a/gio/gsettings.c b/gio/gsettings.c
index ab60fdf71..194a73778 100644
--- a/gio/gsettings.c
+++ b/gio/gsettings.c
@@ -1739,6 +1739,13 @@ g_settings_get_mapped (GSettings           *settings,
       if (okay) goto okay;
     }
 
+  if ((value = g_settings_schema_key_get_per_desktop_default (&skey)))
+    {
+      okay = mapping (value, &result, user_data);
+      g_variant_unref (value);
+      if (okay) goto okay;
+    }
+
   if (mapping (skey.default_value, &result, user_data))
     goto okay;
 
@@ -2646,6 +2653,20 @@ g_settings_binding_key_changed (GSettings   *settings,
         }
     }
 
+  if (variant == NULL)
+    {
+      variant = g_settings_schema_key_get_per_desktop_default (&binding->key);
+      if (variant &&
+          !binding->get_mapping (&value, variant, binding->user_data))
+        {
+          g_error ("Per-desktop default value for key '%s' in schema '%s' "
+                   "was rejected by the binding mapping function.",
+                   binding->key.name, g_settings_schema_get_id (binding->key.schema));
+          g_variant_unref (variant);
+          variant = NULL;
+        }
+    }
+
   if (variant == NULL)
     {
       variant = g_variant_ref (binding->key.default_value);
diff --git a/gio/gsettingsschema-internal.h b/gio/gsettingsschema-internal.h
index f54de3b34..5f996b4bc 100644
--- a/gio/gsettingsschema-internal.h
+++ b/gio/gsettingsschema-internal.h
@@ -37,6 +37,7 @@ struct _GSettingsSchemaKey
   const GVariantType *type;
   GVariant *minimum, *maximum;
   GVariant *default_value;
+  GVariant *desktop_overrides;
 
   gint ref_count;
 };
@@ -58,6 +59,7 @@ gboolean                g_settings_schema_key_type_check                (GSettin
 GVariant *              g_settings_schema_key_range_fixup               (GSettingsSchemaKey *key,
                                                                          GVariant           *value);
 GVariant *              g_settings_schema_key_get_translated_default    (GSettingsSchemaKey *key);
+GVariant *              g_settings_schema_key_get_per_desktop_default   (GSettingsSchemaKey *key);
 
 gint                    g_settings_schema_key_to_enum                   (GSettingsSchemaKey *key,
                                                                          GVariant           *value);
diff --git a/gio/gsettingsschema.c b/gio/gsettingsschema.c
index f1274a369..17b7e3b01 100644
--- a/gio/gsettingsschema.c
+++ b/gio/gsettingsschema.c
@@ -27,6 +27,7 @@
 #include <glibintl.h>
 #include <locale.h>
 #include <string.h>
+#include <stdlib.h>
 
 /**
  * SECTION:gsettingsschema
@@ -1283,6 +1284,11 @@ g_settings_schema_key_init (GSettingsSchemaKey *key,
           endian_fixup (&key->maximum);
           break;
 
+        case 'd':
+          g_variant_get (data, "@a{sv}", &key->desktop_overrides);
+          endian_fixup (&key->desktop_overrides);
+          break;
+
         default:
           g_warning ("unknown schema extension '%c'", code);
           break;
@@ -1303,6 +1309,9 @@ g_settings_schema_key_clear (GSettingsSchemaKey *key)
   if (key->maximum)
     g_variant_unref (key->maximum);
 
+  if (key->desktop_overrides)
+    g_variant_unref (key->desktop_overrides);
+
   g_variant_unref (key->default_value);
 
   g_settings_schema_unref (key->schema);
@@ -1410,6 +1419,35 @@ g_settings_schema_key_get_translated_default (GSettingsSchemaKey *key)
   return value;
 }
 
+GVariant *
+g_settings_schema_key_get_per_desktop_default (GSettingsSchemaKey *key)
+{
+  static const gchar * const *current_desktops;
+  GVariant *value = NULL;
+  gint i;
+
+  if (!key->desktop_overrides)
+    return NULL;
+
+  if (g_once_init_enter (&current_desktops))
+    {
+      const gchar *xdg_current_desktop = g_getenv ("XDG_CURRENT_DESKTOP");
+      gchar **tmp;
+
+      if (xdg_current_desktop != NULL && xdg_current_desktop[0] != '\0')
+        tmp = g_strsplit (xdg_current_desktop, G_SEARCHPATH_SEPARATOR_S, -1);
+      else
+        tmp = g_new0 (gchar *, 0 + 1);
+
+      g_once_init_leave (&current_desktops, (const gchar **) tmp);
+    }
+
+  for (i = 0; value == NULL && current_desktops[i] != NULL; i++)
+    value = g_variant_lookup_value (key->desktop_overrides, current_desktops[i], NULL);
+
+  return value;
+}
+
 gint
 g_settings_schema_key_to_enum (GSettingsSchemaKey *key,
                                GVariant           *value)
@@ -1698,6 +1736,9 @@ g_settings_schema_key_get_default_value (GSettingsSchemaKey *key)
 
   value = g_settings_schema_key_get_translated_default (key);
 
+  if (!value)
+    value = g_settings_schema_key_get_per_desktop_default (key);
+
   if (!value)
     value = g_variant_ref (key->default_value);