[glib/settings-portal: 20/22] settings: Register the keyfile settings backend as extension

[Matthias Clasen <matthiasc src gnome org>]

commit 9a5b9d54638f387e3982775e76d38ea1ce2400df
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Nov 2 22:52:31 2018 -0400

    settings: Register the keyfile settings backend as extension
    
    This was not done previously because you could not create
    a keyfile settings backend instance using g_object_new.
    Fix this by turning the arguments to the new() function into
    construct-only properties. If no filename is specified,
    default to $XDG_CONFIG_HOME/settings.

 gio/giomodule.c                |   1 +
 gio/gkeyfilesettingsbackend.c  | 225 ++++++++++++++++++++++++++++++-----------
 gio/gsettingsbackendinternal.h |   2 +
 3 files changed, 171 insertions(+), 57 deletions(-)
---
diff --git a/gio/giomodule.c b/gio/giomodule.c
index 36c0cefed..8a40aa4ce 100644
--- a/gio/giomodule.c
+++ b/gio/giomodule.c
@@ -1152,6 +1152,7 @@ _g_io_modules_ensure_loaded (void)
       /* Initialize types from built-in "modules" */
       g_type_ensure (g_null_settings_backend_get_type ());
       g_type_ensure (g_memory_settings_backend_get_type ());
+      g_type_ensure (g_keyfile_settings_backend_get_type ());
 #if defined(HAVE_INOTIFY_INIT1)
       g_type_ensure (g_inotify_file_monitor_get_type ());
 #endif
diff --git a/gio/gkeyfilesettingsbackend.c b/gio/gkeyfilesettingsbackend.c
index a37978e83..96a246892 100644
--- a/gio/gkeyfilesettingsbackend.c
+++ b/gio/gkeyfilesettingsbackend.c
@@ -21,6 +21,9 @@
 
 #include "config.h"
 
+#include <glib.h>
+#include <glibintl.h>
+
 #include <stdio.h>
 #include <string.h>
 
@@ -28,7 +31,8 @@
 #include "gfileinfo.h"
 #include "gfilemonitor.h"
 #include "gsimplepermission.h"
-#include "gsettingsbackend.h"
+#include "gsettingsbackendinternal.h"
+#include "giomodule.h"
 
 
 #define G_TYPE_KEYFILE_SETTINGS_BACKEND      (g_keyfile_settings_backend_get_type ())
@@ -41,6 +45,13 @@
 
 typedef GSettingsBackendClass GKeyfileSettingsBackendClass;
 
+enum {
+  PROP_0,
+  PROP_FILENAME,
+  PROP_ROOT_PATH,
+  PROP_ROOT_GROUP
+};
+
 typedef struct
 {
   GSettingsBackend   parent_instance;
@@ -54,6 +65,7 @@ typedef struct
   gchar             *root_group;
   gint               root_group_len;
 
+  char              *filename;
   GFile             *file;
   GFileMonitor      *file_monitor;
   guint8             digest[32];
@@ -61,10 +73,11 @@ typedef struct
   GFileMonitor      *dir_monitor;
 } GKeyfileSettingsBackend;
 
-static GType g_keyfile_settings_backend_get_type (void);
-G_DEFINE_TYPE (GKeyfileSettingsBackend,
-               g_keyfile_settings_backend,
-               G_TYPE_SETTINGS_BACKEND)
+G_DEFINE_TYPE_WITH_CODE (GKeyfileSettingsBackend,
+                         g_keyfile_settings_backend,
+                         G_TYPE_SETTINGS_BACKEND,
+                         g_io_extension_point_implement (G_SETTINGS_BACKEND_EXTENSION_POINT_NAME,
+                                                         g_define_type_id, "keyfile", 10))
 
 static void
 compute_checksum (guint8        *digest,
@@ -512,6 +525,7 @@ g_keyfile_settings_backend_finalize (GObject *object)
 
   g_free (kfsb->root_group);
   g_free (kfsb->prefix);
+  g_free (kfsb->filename);
 
   G_OBJECT_CLASS (g_keyfile_settings_backend_parent_class)
     ->finalize (object);
@@ -522,25 +536,6 @@ g_keyfile_settings_backend_init (GKeyfileSettingsBackend *kfsb)
 {
 }
 
-static void
-g_keyfile_settings_backend_class_init (GKeyfileSettingsBackendClass *class)
-{
-  GObjectClass *object_class = G_OBJECT_CLASS (class);
-
-  object_class->finalize = g_keyfile_settings_backend_finalize;
-
-  class->read = g_keyfile_settings_backend_read;
-  class->write = g_keyfile_settings_backend_write;
-  class->write_tree = g_keyfile_settings_backend_write_tree;
-  class->reset = g_keyfile_settings_backend_reset;
-  class->get_writable = g_keyfile_settings_backend_get_writable;
-  class->get_permission = g_keyfile_settings_backend_get_permission;
-  /* No need to implement subscribed/unsubscribe: the only point would be to
-   * stop monitoring the file when there's no GSettings anymore, which is no
-   * big win.
-   */
-}
-
 static void
 file_changed (GFileMonitor      *monitor,
               GFile             *file,
@@ -567,6 +562,150 @@ dir_changed (GFileMonitor       *monitor,
   g_keyfile_settings_backend_keyfile_writable (kfsb);
 }
 
+static void
+g_keyfile_settings_backend_constructed (GObject *object)
+{
+  GKeyfileSettingsBackend *kfsb = G_KEYFILE_SETTINGS_BACKEND (object);
+
+  if (kfsb->filename == NULL)
+    kfsb->filename = g_build_filename (g_get_user_config_dir (), "settings", NULL);
+
+  if (kfsb->prefix == NULL)
+    {
+      kfsb->prefix = g_strdup ("/");
+      kfsb->prefix_len = 1;
+    }
+  
+  kfsb->keyfile = g_key_file_new ();
+  kfsb->permission = g_simple_permission_new (TRUE);
+
+  kfsb->file = g_file_new_for_path (kfsb->filename);
+  kfsb->dir = g_file_get_parent (kfsb->file);
+  g_file_make_directory_with_parents (kfsb->dir, NULL, NULL);
+
+  kfsb->file_monitor = g_file_monitor (kfsb->file, 0, NULL, NULL);
+  kfsb->dir_monitor = g_file_monitor (kfsb->dir, 0, NULL, NULL);
+
+  compute_checksum (kfsb->digest, NULL, 0);
+
+  g_signal_connect (kfsb->file_monitor, "changed",
+                    G_CALLBACK (file_changed), kfsb);
+  g_signal_connect (kfsb->dir_monitor, "changed",
+                    G_CALLBACK (dir_changed), kfsb);
+
+  g_keyfile_settings_backend_keyfile_writable (kfsb);
+  g_keyfile_settings_backend_keyfile_reload (kfsb);
+}
+
+static void
+g_keyfile_settings_backend_set_property (GObject      *object,
+                                         guint         prop_id,
+                                         const GValue *value,
+                                         GParamSpec   *pspec)
+{
+  GKeyfileSettingsBackend *kfsb = G_KEYFILE_SETTINGS_BACKEND (object);
+
+  switch (prop_id)
+    {
+    case PROP_FILENAME:
+      kfsb->filename = g_value_dup_string (value);
+      break;
+
+    case PROP_ROOT_PATH:
+      kfsb->prefix = g_value_dup_string (value);
+      if (kfsb->prefix)
+        kfsb->prefix_len = strlen (kfsb->prefix);
+      break;
+
+    case PROP_ROOT_GROUP:
+      kfsb->root_group = g_value_dup_string (value);
+      if (kfsb->root_group)
+        kfsb->root_group_len = strlen (kfsb->root_group);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+g_keyfile_settings_backend_get_property (GObject    *object,
+                                         guint       prop_id,
+                                         GValue     *value,
+                                         GParamSpec *pspec)
+{
+  GKeyfileSettingsBackend *kfsb = G_KEYFILE_SETTINGS_BACKEND (object);
+
+  switch (prop_id)
+    {
+    case PROP_FILENAME:
+      g_value_set_string (value, kfsb->filename);
+      break;
+
+    case PROP_ROOT_PATH:
+      g_value_set_string (value, kfsb->prefix);
+      break;
+
+    case PROP_ROOT_GROUP:
+      g_value_set_string (value, kfsb->root_group);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+      break;
+    }
+}
+
+static void
+g_keyfile_settings_backend_class_init (GKeyfileSettingsBackendClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->finalize = g_keyfile_settings_backend_finalize;
+  object_class->constructed = g_keyfile_settings_backend_constructed;
+  object_class->get_property = g_keyfile_settings_backend_get_property;
+  object_class->set_property = g_keyfile_settings_backend_set_property;
+
+  class->read = g_keyfile_settings_backend_read;
+  class->write = g_keyfile_settings_backend_write;
+  class->write_tree = g_keyfile_settings_backend_write_tree;
+  class->reset = g_keyfile_settings_backend_reset;
+  class->get_writable = g_keyfile_settings_backend_get_writable;
+  class->get_permission = g_keyfile_settings_backend_get_permission;
+  /* No need to implement subscribed/unsubscribe: the only point would be to
+   * stop monitoring the file when there's no GSettings anymore, which is no
+   * big win.
+   */
+
+  g_object_class_install_property (object_class,
+                                   PROP_FILENAME,
+                                   g_param_spec_string ("filename",
+                                                        P_("Filename"),
+                                                        P_("The filename"),
+                                                        NULL,
+                                                        G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+                                                        G_PARAM_STATIC_STRINGS));
+
+  g_object_class_install_property (object_class,
+                                   PROP_ROOT_PATH,
+                                   g_param_spec_string ("root-path",
+                                                        P_("Root path"),
+                                                        P_("The root path"),
+                                                        NULL,
+                                                        G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+                                                        G_PARAM_STATIC_STRINGS));
+
+  g_object_class_install_property (object_class,
+                                   PROP_ROOT_GROUP,
+                                   g_param_spec_string ("root-group",
+                                                        P_("Root group"),
+                                                        P_("The root group"),
+                                                        NULL,
+                                                        G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY |
+                                                        G_PARAM_STATIC_STRINGS));
+}
+
 /**
  * g_keyfile_settings_backend_new:
  * @filename: the filename of the keyfile
@@ -626,43 +765,15 @@ g_keyfile_settings_backend_new (const gchar *filename,
                                 const gchar *root_path,
                                 const gchar *root_group)
 {
-  GKeyfileSettingsBackend *kfsb;
-
   g_return_val_if_fail (filename != NULL, NULL);
   g_return_val_if_fail (root_path != NULL, NULL);
   g_return_val_if_fail (g_str_has_prefix (root_path, "/"), NULL);
   g_return_val_if_fail (g_str_has_suffix (root_path, "/"), NULL);
   g_return_val_if_fail (strstr (root_path, "//") == NULL, NULL);
 
-  kfsb = g_object_new (G_TYPE_KEYFILE_SETTINGS_BACKEND, NULL);
-  kfsb->keyfile = g_key_file_new ();
-  kfsb->permission = g_simple_permission_new (TRUE);
-
-  kfsb->file = g_file_new_for_path (filename);
-  kfsb->dir = g_file_get_parent (kfsb->file);
-  g_file_make_directory_with_parents (kfsb->dir, NULL, NULL);
-
-  kfsb->file_monitor = g_file_monitor (kfsb->file, 0, NULL, NULL);
-  kfsb->dir_monitor = g_file_monitor (kfsb->dir, 0, NULL, NULL);
-
-  kfsb->prefix_len = strlen (root_path);
-  kfsb->prefix = g_strdup (root_path);
-
-  if (root_group)
-    {
-      kfsb->root_group_len = strlen (root_group);
-      kfsb->root_group = g_strdup (root_group);
-    }
-
-  compute_checksum (kfsb->digest, NULL, 0);
-
-  g_signal_connect (kfsb->file_monitor, "changed",
-                    G_CALLBACK (file_changed), kfsb);
-  g_signal_connect (kfsb->dir_monitor, "changed",
-                    G_CALLBACK (dir_changed), kfsb);
-
-  g_keyfile_settings_backend_keyfile_writable (kfsb);
-  g_keyfile_settings_backend_keyfile_reload (kfsb);
-
-  return G_SETTINGS_BACKEND (kfsb);
+  return G_SETTINGS_BACKEND (g_object_new (G_TYPE_KEYFILE_SETTINGS_BACKEND,
+                                           "filename", filename,
+                                           "root-path", root_path,
+                                           "root-group", root_group,
+                                           NULL));
 }
diff --git a/gio/gsettingsbackendinternal.h b/gio/gsettingsbackendinternal.h
index 2a76a80bc..9e1d51dba 100644
--- a/gio/gsettingsbackendinternal.h
+++ b/gio/gsettingsbackendinternal.h
@@ -87,6 +87,8 @@ GType                   g_null_settings_backend_get_type                (void);
 
 GType                   g_memory_settings_backend_get_type              (void);
 
+GType                   g_keyfile_settings_backend_get_type             (void);
+
 #ifdef HAVE_COCOA
 GType                   g_nextstep_settings_backend_get_type            (void);
 #endif