c++11 : add chrono based auto timer

include/mapnik/util/timer.hpp

@@ -0,0 +1,51 @@
+/* This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2013 Artem Pavlenko
+ *
+ * Mapnik is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifndef MAPNIK_UTIL_TIMER_HPP
+#define MAPNIK_UTIL_TIMER_HPP
+
+#include <string>
+#include <chrono>
+
+namespace mapnik {
+
+class auto_cpu_timer
+{
+public:
+    auto_cpu_timer(std::ostream & os, std::string const& message)
+        : start_(std::chrono::system_clock::now()),
+          os_(os),
+          message_(message) {}
+
+    ~auto_cpu_timer()
+    {
+        std::chrono::duration<double,std::milli> elapsed = std::chrono::system_clock::now() - start_;
+        os_ << message_ << std::chrono::duration_cast<std::chrono::milliseconds>(elapsed).count() << " ms" << std::endl;
+    }
+private:
+    std::chrono::time_point<std::chrono::system_clock> start_;
+    std::ostream & os_;
+    std::string message_;
+};
+
+// NOTE : add more timers here
+
+}
+
+#endif // MAPNIK_UTIL_TIMER_HPP