Extensions. Fix live preview crash in custom color extension when invalid values...

diff --git a/share/extensions/color_custom.py b/share/extensions/color_custom.py
index 1b866f68485315b649360e534aa62e5455ea6df9..07c554fa5a98d8e5ec4817aa75615d9dc1cff35f 100644 (file)
--- a/share/extensions/color_custom.py
+++ b/share/extensions/color_custom.py
@@ -6,20 +6,32 @@ class C(coloreffect.ColorEffect):
     self.OptionParser.add_option("--r", action="store", type="string", dest="rFunction", default="r",help="red channel function")
     self.OptionParser.add_option("--g", action="store", type="string", dest="gFunction", default="g",help="green channel function")
     self.OptionParser.add_option("--b", action="store", type="string", dest="bFunction", default="b",help="blue channel function")
+
   def normalize(self, v):
     if v<0:
       return 0.0
     if v>1:
       return 1.0
     return v
+
+  def _hexstr(self,r,g,b):
+    return '%02x%02x%02x' % (int(round(r*255)),int(round(g*255)),int(round(b*255)))
+  
   def colmod(self,_r,_g,_b):
     r=float(_r)/255
     g=float(_g)/255
     b=float(_b)/255
-    r2=self.normalize(eval(self.options.rFunction))
-    g2=self.normalize(eval(self.options.gFunction))
-    b2=self.normalize(eval(self.options.bFunction))
-    return '%02x%02x%02x' % (int(round(r2*255)),int(round(g2*255)),int(round(b2*255)))
+    
+    # add stuff to be accessible from within the custom color function here.
+    safeenv = {'__builtins__':{},'r':r,'g':g,'b':b}
+
+    try:
+      r2=self.normalize(eval(self.options.rFunction,safeenv))
+      g2=self.normalize(eval(self.options.gFunction,safeenv))
+      b2=self.normalize(eval(self.options.bFunction,safeenv))
+    except:
+      return self._hexstr(1.0,0.0,0.0)
+    return self._hexstr(r2,g2,b2)
 
 c = C()
-c.affect()
\ No newline at end of file
+c.affect()