Reload theme on SIGHUP signal

Fixes #28

Allows for users/applications to request a theme reload
by sending SIGHUP signal to the daemon.

README.md

@@ -95,6 +95,10 @@ You can add your own themes in one of two ways:
    $ sudo cp my_awesome_theme.json /usr/local/share/feedbackd/themes/
    ```
 
+Upon reception of `SIGHUP` signal, the daemon process will proceed to retrigger
+the above logic to find the themes, and reload the corresponding one. This can
+be used to avoid having to restart the daemon in case of configuration changes.
+
 Check out the companion [feedbackd-device-themes][1] repository for a
 selection of device-specific themes. In order for your theme to be recognized
 it must be named properly. Currently, theme names are based on the `compatible`

src/fbd-feedback-manager.c

@@ -492,29 +492,11 @@ find_themefile (void)
 static void
 fbd_feedback_manager_constructed (GObject *object)
 {
-  g_autoptr (GError) err = NULL;
   FbdFeedbackManager *self = FBD_FEEDBACK_MANAGER (object);
-  const gchar *themefile;
 
   G_OBJECT_CLASS (fbd_feedback_manager_parent_class)->constructed (object);
 
-  // Overide themefile with environment variable if requested
-  themefile = g_getenv (FEEDBACKD_THEME_VAR);
-
-  // Search for device-specific configuration
-  if (!themefile)
-    themefile = find_themefile ();
-
-  // Fallback to default configuration if needed
-  if (!themefile)
-    themefile = FEEDBACKD_THEME_DIR "/default.json";
-  g_info ("Using themefile: %s", themefile);
-
-  self->theme = fbd_feedback_theme_new_from_file (themefile, &err);
-  if (!self->theme) {
-    /* No point to carry on */
-    g_error ("Failed to load theme: %s", err->message);
-  }
+  fbd_feedback_manager_load_theme(self);
 
   g_signal_connect (self, "notify::profile", (GCallback)on_profile_changed, NULL);
   lfb_gdbus_feedback_set_profile (LFB_GDBUS_FEEDBACK (self),
@@ -617,6 +599,34 @@ fbd_feedback_manager_get_dev_leds (FbdFeedbackManager *self)
   return self->leds;
 }
 
+void fbd_feedback_manager_load_theme (FbdFeedbackManager *self) {
+  g_autoptr (GError) err = NULL;
+  g_autoptr (FbdFeedbackTheme) theme = NULL;
+  const gchar *themefile;
+
+  // Overide themefile with environment variable if requested
+  themefile = g_getenv (FEEDBACKD_THEME_VAR);
+
+  // Search for device-specific configuration
+  if (!themefile)
+    themefile = find_themefile ();
+
+  // Fallback to default configuration if needed
+  if (!themefile)
+    themefile = FEEDBACKD_THEME_DIR "/default.json";
+  g_info ("Using themefile: %s", themefile);
+
+  theme = fbd_feedback_theme_new_from_file (themefile, &err);
+  if (theme) {
+    g_set_object(&self->theme, theme);
+  } else {
+    if (self->theme)
+      g_warning ("Failed to reload theme: %s", err->message);
+    else
+      g_error ("Failed to load theme: %s", err->message); // No point to carry on
+  }
+}
+
 gboolean
 fbd_feedback_manager_set_profile (FbdFeedbackManager *self, const gchar *profile)
 {

src/fbd-feedback-manager.h

@@ -22,6 +22,7 @@ FbdFeedbackManager *fbd_feedback_manager_get_default (void);
 FbdDevVibra *fbd_feedback_manager_get_dev_vibra (FbdFeedbackManager *self);
 FbdDevSound *fbd_feedback_manager_get_dev_sound (FbdFeedbackManager *self);
 FbdDevLeds  *fbd_feedback_manager_get_dev_leds  (FbdFeedbackManager *self);
+void         fbd_feedback_manager_load_theme    (FbdFeedbackManager *self);
 gboolean     fbd_feedback_manager_set_profile (FbdFeedbackManager *self, const gchar *profile);
 
 G_END_DECLS

src/fbd.c

@@ -42,6 +42,18 @@ quit_cb (gpointer user_data)
     return FALSE;
 }
 
+static gboolean
+reload_cb (gpointer user_data)
+{
+  FbdFeedbackManager *manager = fbd_feedback_manager_get_default();
+
+  g_return_val_if_fail (FBD_IS_FEEDBACK_MANAGER (manager), FALSE);
+
+  g_debug ("Caught signal, reloading feedback theme...");
+  fbd_feedback_manager_load_theme (manager);
+
+  return TRUE;
+}
 
 static void
 bus_acquired_cb (GDBusConnection *connection,
@@ -102,6 +114,7 @@ int main(int argc, char *argv[])
 
   g_unix_signal_add (SIGTERM, quit_cb, NULL);
   g_unix_signal_add (SIGINT, quit_cb, NULL);
+  g_unix_signal_add (SIGHUP, reload_cb, NULL);
 
   loop = g_main_loop_new (NULL, FALSE);