[gnome-settings-daemon] power: Guard against dividing by 0 in ABS_TO_PERCENTAGE macro

[Rodrigo Moya <rodrigo src gnome org>]

commit fcd4e082cc1528b633b7d07732adb2921d244ab8
Author: Rodrigo Moya <rodrigo gnome-db org>
Date:   Wed Sep 7 12:34:40 2011 +0200

    power: Guard against dividing by 0 in ABS_TO_PERCENTAGE macro
    
    https://bugzilla.gnome.org/show_bug.cgi?id=657364

 plugins/power/gsd-power-manager.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/plugins/power/gsd-power-manager.c b/plugins/power/gsd-power-manager.c
index a67c998..c6aef22 100644
--- a/plugins/power/gsd-power-manager.c
+++ b/plugins/power/gsd-power-manager.c
@@ -126,7 +126,7 @@ static const gchar introspection_xml[] =
 #define BRIGHTNESS_STEP_AMOUNT(max) ((max) < 20 ? 1 : (max) / 20)
 
 /* take a discrete value with offset and convert to percentage */
-#define ABS_TO_PERCENTAGE(min, max, value) (((value - min) * 100) / (max - min))
+#define ABS_TO_PERCENTAGE(min, max, value) (((value - min) * 100) / ((max - min) ? (max - min) : 1))
 #define PERCENTAGE_TO_ABS(min, max, value) (min + (((max - min) * value) / 100))
 
 #define GSD_POWER_MANAGER_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), GSD_TYPE_POWER_MANAGER, GsdPowerManagerPrivate))