xcpmd: Send battery changed when the percent changes

xcpmd polls the battery every 4 seconds. When running on battery, *something* will have changed in that time. Even on AC, the values have typically changes such that xcpmd is sending the DBus notification. However, the only thing that the UI cares about is the battery percentage. So check the percentage and only send it if has changed. This avoids xcpmd sending a message, but it also removes multiple DBus queries by the UI for more information. It's a little bit of a micro optimization, but it is also easy. Signed-off-by: Jason Andryuk <[email protected]>
OpenXT · Jul 25, 2022 · 7cd378d · 7cd378d
1 parent 6decdfb
commit 7cd378d
Showing 1 changed file with 10 additions and 3 deletions.
diff --git a/xcpmd/src/battery.c b/xcpmd/src/battery.c
@@ -911,9 +911,16 @@ void update_batteries(void) {
     }
 
     if ((old_array_size != new_array_size) || (memcmp(old_status, last_status, new_array_size * sizeof(struct battery_status)))) {
-        //Here for compatibility--should eventually be removed
-        xenstore_write("1", XS_BATTERY_STATUS_CHANGE_EVENT_PATH);
-        notify_com_citrix_xenclient_xcpmd_battery_status_changed(xcdbus_conn, XCPMD_SERVICE, XCPMD_PATH, get_overall_battery_percentage());
+        static int previous_percent;
+        int current_percent = get_overall_battery_percentage();
+
+        if (current_percent != previous_percent)  {
+            previous_percent = current_percent;
+            //Here for compatibility--should eventually be removed
+            xenstore_write("1", XS_BATTERY_STATUS_CHANGE_EVENT_PATH);
+            notify_com_citrix_xenclient_xcpmd_battery_status_changed(
+                xcdbus_conn, XCPMD_SERVICE, XCPMD_PATH, current_percent);
+        }
     }
 
     if (present_batteries_changed) {