state: add save_after_timeout() method to replace all custom timeout code

This was a common pattern that we had in many places, so it makes sense
to consolidate it.

lib/wp/state.c

@@ -15,6 +15,7 @@
 
 WP_DEFINE_LOCAL_LOG_TOPIC ("wp-state")
 
+#define DEFAULT_TIMEOUT_MS 1000
 #define ESCAPED_CHARACTER '\\'
 
 static char *
@@ -123,6 +124,7 @@ compress_string (const gchar *str)
 enum {
   PROP_0,
   PROP_NAME,
+  PROP_TIMEOUT,
 };
 
 struct _WpState
@@ -131,9 +133,11 @@ struct _WpState
 
   /* Props */
   gchar *name;
+  guint timeout;
 
   gchar *location;
-  GKeyFile *keyfile;
+  GSource *timeout_source;
+  WpProperties *timeout_props;
 };
 
 G_DEFINE_TYPE (WpState, wp_state, G_TYPE_OBJECT)
@@ -186,6 +190,9 @@ wp_state_set_property (GObject * object, guint property_id,
     g_clear_pointer (&self->name, g_free);
     self->name = g_value_dup_string (value);
     break;
+  case PROP_TIMEOUT:
+    self->timeout = g_value_get_uint (value);
+    break;
   default:
     G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     break;
@@ -202,6 +209,9 @@ wp_state_get_property (GObject * object, guint property_id, GValue * value,
   case PROP_NAME:
     g_value_set_string (value, self->name);
     break;
+  case PROP_TIMEOUT:
+    g_value_set_uint (value, self->timeout);
+    break;
   default:
     G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
     break;
@@ -215,6 +225,8 @@ wp_state_finalize (GObject * object)
 
   g_clear_pointer (&self->name, g_free);
   g_clear_pointer (&self->location, g_free);
+  g_clear_pointer (&self->timeout_source, g_source_unref);
+  g_clear_pointer (&self->timeout_props, wp_properties_unref);
 
   G_OBJECT_CLASS (wp_state_parent_class)->finalize (object);
 }
@@ -222,6 +234,7 @@ wp_state_finalize (GObject * object)
 static void
 wp_state_init (WpState * self)
 {
+  self->timeout = DEFAULT_TIMEOUT_MS;
 }
 
 static void
@@ -237,6 +250,11 @@ wp_state_class_init (WpStateClass * klass)
       g_param_spec_string ("name", "name",
           "The file name where the state will be stored", NULL,
           G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS));
+
+  g_object_class_install_property (object_class, PROP_TIMEOUT,
+      g_param_spec_uint ("timeout", "timeout",
+          "The timeout in milliseconds to save the state", 0, G_MAXUINT,
+          DEFAULT_TIMEOUT_MS, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 }
 
 /*!
@@ -339,6 +357,57 @@ wp_state_save (WpState *self, WpProperties *props, GError ** error)
   return TRUE;
 }
 
+static gboolean
+timeout_save_state_callback (WpState *self)
+{
+  g_autoptr (GError) error = NULL;
+
+  if (!wp_state_save (self, self->timeout_props, &error))
+    wp_warning_object (self, "%s", error->message);
+
+  g_clear_pointer (&self->timeout_source, g_source_unref);
+  g_clear_pointer (&self->timeout_props, wp_properties_unref);
+
+  return G_SOURCE_REMOVE;
+}
+
+/*!
+ * \brief Saves new properties in the state, overwriting all previous data,
+ *   after a timeout
+ *
+ * This is similar to wp_state_save() but it will save the state after a timeout
+ * has elapsed. If the state is saved again before the timeout elapses, the
+ * timeout is reset.
+ *
+ * This function is useful to avoid saving the state too often. When called
+ * consecutively, it will save the state only once. Every time it is called,
+ * it will cancel the previous timer and start a new one, resulting in timing
+ * out only after the last call.
+ *
+ * \ingroup wpstate
+ * \param self the state
+ * \param core the core, used to add the timeout callback to the main loop
+ * \param props (transfer none): the properties to save. This object will be
+ *   referenced and kept alive until the timeout elapses, but not deep copied.
+ * \since 0.5.0
+ */
+void
+wp_state_save_after_timeout (WpState *self, WpCore *core, WpProperties *props)
+{
+  /* Clear the current timeout callback */
+  if (self->timeout_source)
+    g_source_destroy (self->timeout_source);
+  g_clear_pointer (&self->timeout_source, g_source_unref);
+  g_clear_pointer (&self->timeout_props, wp_properties_unref);
+
+  self->timeout_props = wp_properties_ref (props);
+
+  /* Add the timeout callback */
+  wp_core_timeout_add_closure (core, &self->timeout_source, self->timeout,
+      g_cclosure_new_object (G_CALLBACK (timeout_save_state_callback),
+          G_OBJECT (self)));
+}
+
 /*!
  * \brief Loads the state data from the file system
  *

lib/wp/state.h

@@ -10,6 +10,7 @@
 #define __WIREPLUMBER_STATE_H__
 
 #include "properties.h"
+#include "core.h"
 
 G_BEGIN_DECLS
 
@@ -38,6 +39,10 @@ void wp_state_clear (WpState *self);
 WP_API
 gboolean wp_state_save (WpState *self, WpProperties *props, GError ** error);
 
+WP_API
+void wp_state_save_after_timeout (WpState *self, WpCore *core,
+    WpProperties *props);
+
 WP_API
 WpProperties * wp_state_load (WpState *self);
 

modules/module-lua-scripting/api/api.c

@@ -1522,6 +1522,16 @@ state_save (lua_State *L)
   return 2;
 }
 
+static int
+state_save_after_timeout (lua_State *L)
+{
+  WpState *state = wplua_checkobject (L, 1, WP_TYPE_STATE);
+  luaL_checktype (L, 2, LUA_TTABLE);
+  g_autoptr (WpProperties) props = wplua_table_to_properties (L, 2);
+  wp_state_save_after_timeout (state, get_wp_core (L), props);
+  return 0;
+}
+
 static int
 state_load (lua_State *L)
 {
@@ -1534,6 +1544,7 @@ state_load (lua_State *L)
 static const luaL_Reg state_methods[] = {
   { "clear", state_clear },
   { "save" , state_save },
+  { "save_after_timeout", state_save_after_timeout },
   { "load" , state_load },
   { NULL, NULL }
 };

modules/module-settings.c

@@ -34,7 +34,6 @@ struct _WpSettingsPlugin
   WpImplMetadata *impl_metadata;
   WpState *state;
   WpProperties *settings;
-  GSource *timeout_source;
 };
 
 enum {
@@ -49,46 +48,18 @@ G_DEFINE_TYPE (WpSettingsPlugin, wp_settings_plugin, WP_TYPE_PLUGIN)
 
 #define NAME "sm-settings"
 #define PERSISTENT_SETTING "persistent.settings"
-#define SAVE_INTERVAL_MS 1000
 
 static void
 wp_settings_plugin_init (WpSettingsPlugin * self)
 {
 }
 
-static gboolean
-timeout_save_state_callback (WpSettingsPlugin *self)
-{
-  g_autoptr (GError) error = NULL;
-
-  if (!wp_state_save (self->state, self->settings, &error))
-    wp_warning_object (self, "%s", error->message);
-
-  return G_SOURCE_REMOVE;
-}
-
-static void
-timeout_save_settings (WpSettingsPlugin *self, guint ms)
-{
-  g_autoptr (WpCore) core = wp_object_get_core (WP_OBJECT (self));
-  g_return_if_fail (core);
-
-  /* Clear the current timeout callback */
-  if (self->timeout_source)
-    g_source_destroy (self->timeout_source);
-  g_clear_pointer (&self->timeout_source, g_source_unref);
-
-  /* Add the timeout callback */
-  wp_core_timeout_add_closure (core, &self->timeout_source, ms,
-      g_cclosure_new_object (G_CALLBACK (timeout_save_state_callback),
-      G_OBJECT (self)));
-}
-
 static void
 on_metadata_changed (WpMetadata *m, guint32 subject,
    const gchar *setting, const gchar *type, const gchar *new_value, gpointer d)
 {
   WpSettingsPlugin *self = WP_SETTINGS_PLUGIN(d);
+  g_autoptr (WpCore) core = wp_object_get_core (WP_OBJECT (self));
   const gchar *old_value = wp_properties_get (self->settings, setting);
 
   if (!old_value) {
@@ -102,7 +73,7 @@ on_metadata_changed (WpMetadata *m, guint32 subject,
   wp_properties_set (self->settings, setting, new_value);
 
   /* update the state */
-  timeout_save_settings (self, SAVE_INTERVAL_MS);
+  wp_state_save_after_timeout (self->state, core, self->settings);
 }
 
 WpProperties *
@@ -220,7 +191,7 @@ on_metadata_activated (WpMetadata * m, GAsyncResult * res, gpointer user_data)
 
     g_clear_pointer (&self->settings, wp_properties_unref);
     self->settings = g_steal_pointer (&config_settings);
-    timeout_save_settings (self, SAVE_INTERVAL_MS);
+    wp_state_save_after_timeout (self->state, core, self->settings);
   } else {
     wp_info_object (self, PERSISTENT_SETTING
        " is enabled, current saved settings will be used");
@@ -277,10 +248,6 @@ wp_settings_plugin_disable (WpPlugin * plugin)
 {
   WpSettingsPlugin * self = WP_SETTINGS_PLUGIN (plugin);
 
-  if (self->timeout_source)
-    g_source_destroy (self->timeout_source);
-  g_clear_pointer (&self->timeout_source, g_source_unref);
-
   g_clear_object (&self->impl_metadata);
   g_clear_pointer (&self->settings, wp_properties_unref);
   g_clear_object (&self->state);

src/scripts/default-nodes/state-default-nodes.lua

@@ -10,7 +10,6 @@
 -- state file during the bootup, finally it has a hook which finds a default
 -- node out of the user preferences
 
-cutils = require ("common-utils")
 settings = require ("settings-node")
 log = Log.open_topic ("s-default-nodes")
 
@@ -175,7 +174,7 @@ function updateStored (def_node_type, stored)
     index = index + 1
   until v == nil
 
-  cutils.storeAfterTimeout (state, state_table)
+  state:save_after_timeout (state_table)
 end
 
 function toggleState (enable)

src/scripts/device/autoswitch-bluetooth-profile.lua

@@ -87,7 +87,7 @@ streams_om = ObjectManager {
 local function saveHeadsetProfile (device, profile_name)
   local key = "saved-headset-profile:" .. device.properties ["device.name"]
   headset_profiles [key] = profile_name
-  cutils.storeAfterTimeout (state, headset_profiles)
+  state:save_after_timeout (headset_profiles)
 end
 
 local function getSavedHeadsetProfile (device)

src/scripts/device/state-profile.lua

@@ -119,7 +119,7 @@ function updateStoredProfile (device, profile)
   end
 
   state_table[dev_name] = profile.name
-  cutils.storeAfterTimeout (state, state_table)
+  state:save_after_timeout (state_table)
 
   log:info (device, string.format (
       "stored profile '%s' (%d) for device '%s'",

src/scripts/device/state-routes.lua

@@ -242,7 +242,7 @@ function saveRouteProps (dev_info, route)
     iec958Codecs = props.iec958Codecs and Json.Array (props.iec958Codecs),
   }:to_string ()
 
-  cutils.storeAfterTimeout (state, state_table)
+  state:save_after_timeout (state_table)
 end
 
 function getStoredRouteProps (dev_info, route)
@@ -273,7 +273,7 @@ function saveProfileRoutes (dev_info, profile_name)
   if #routes > 0 then
     local key = dev_info.name .. ":profile:" .. profile_name
     state_table [key] = Json.Array (routes):to_string()
-    cutils.storeAfterTimeout (state, state_table)
+    state:save_after_timeout (state_table)
   end
 end
 

src/scripts/lib/common-utils.lua

@@ -108,23 +108,6 @@ function cutils.arrayContains (a, value)
   return false
 end
 
-state_save_sources = {}
-
-function cutils.storeAfterTimeout (state, state_table)
-  local state_name = state["name"]
-  if state_save_sources [state_name] ~= nil then
-    state_save_sources [state_name]:destroy ()
-    state_save_sources [state_name] = nil
-  end
-  state_save_sources [state_name] = Core.timeout_add (1000, function ()
-    local saved, err = state:save (state_table)
-    if not saved then
-      Log.warning (err)
-    end
-    return false
-  end)
-end
-
 function cutils.get_application_name ()
   return Core.get_properties()["application.name"] or "WirePlumber"
 end

src/scripts/node/state-stream.lua

@@ -387,7 +387,7 @@ function saveStreamProps (key, p)
   p.channelVolumes = p.channelVolumes and Json.Array (p.channelVolumes)
 
   state_table [key] = Json.Object (p):to_string ()
-  cutils.storeAfterTimeout (state, state_table)
+  state:save_after_timeout (state_table)
 end
 
 function formKey (properties)