Add a limit on the number of points in a GPS trace

lib/gpx.rb

@@ -6,8 +6,9 @@ module GPX
 
     attr_reader :possible_points, :actual_points, :tracksegs
 
-    def initialize(file)
+    def initialize(file, options = {})
       @file = file
+      @maximum_points = options[:maximum_points] || Float::INFINITY
     end
 
     def parse_file(reader)
@@ -19,6 +20,7 @@ module GPX
           if reader.name == "trkpt"
             point = TrkPt.new(@tracksegs, reader["lat"].to_f, reader["lon"].to_f)
             @possible_points += 1
+            raise FileTooBigError if @possible_points > @maximum_points
           elsif reader.name == "ele" && point
             point.altitude = reader.read_string.to_f
           elsif reader.name == "time" && point
@@ -172,4 +174,10 @@ module GPX
         longitude >= -180 && longitude <= 180
     end
   end
+
+  class FileTooBigError < RuntimeError
+    def initialise
+      super("GPX File contains too many points")
+    end
+  end
 end