New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/base/timer.hpp

@@ -0,0 +1,105 @@
+#pragma once
+
+#include <chrono>
+#include <cstdint>
+#include <ctime>
+#include <string>
+
+namespace base
+{
+namespace impl
+{
+template <class ClockT> class StdTimer
+{
+  typename ClockT::time_point m_startTime;
+
+public:
+  explicit StdTimer(bool start = true)
+  {
+    if (start)
+      Reset();
+  }
+
+  using DurationT = typename ClockT::duration;
+  /// @return Elapsed time from start (@see Reset).
+  DurationT TimeElapsed() const { return ClockT::now() - m_startTime; }
+
+  template <typename Duration>
+  Duration TimeElapsedAs() const
+  {
+    return std::chrono::duration_cast<Duration>(TimeElapsed());
+  }
+
+  double ElapsedSeconds() const { return TimeElapsedAs<std::chrono::duration<double>>().count(); }
+  uint64_t ElapsedMilliseconds() const { return TimeElapsedAs<std::chrono::milliseconds>().count(); }
+  uint64_t ElapsedNanoseconds() const { return TimeElapsedAs<std::chrono::nanoseconds>().count(); }
+
+  void Reset() { m_startTime = ClockT::now(); }
+};
+} // namespace impl
+
+
+/// Cross platform timer
+class Timer : public impl::StdTimer<std::chrono::steady_clock>
+{
+  using BaseT = impl::StdTimer<std::chrono::steady_clock>;
+
+public:
+  using BaseT::BaseT;
+
+  /// @return current UTC time in seconds, elapsed from 1970.
+  static double LocalTime();
+};
+
+std::string FormatCurrentTime();
+
+/// Generates timestamp for a specified day.
+/// \param year     The number of years since 1900.
+/// \param month    The number of month since January, in the range 0 to 11.
+/// \param day      The day of the month, in the range 1 to 31.
+/// \return Timestamp.
+uint32_t GenerateYYMMDD(int year, int month, int day);
+uint32_t GenerateYYMMDD(uint64_t secondsSinceEpoch);
+uint64_t YYMMDDToSecondsSinceEpoch(uint32_t yymmdd);
+
+uint64_t SecondsSinceEpoch();
+
+/// Always creates strings in UTC time: 1997-07-16T07:30:15Z
+/// Returns empty string on error
+std::string TimestampToString(time_t time);
+
+std::string SecondsSinceEpochToString(uint64_t secondsSinceEpoch);
+
+time_t const INVALID_TIME_STAMP = -1;
+
+/// Accepts strings in UTC format: 1997-07-16T07:30:15Z
+/// And with custom time offset:   1997-07-16T10:30:15+03:00
+/// @return INVALID_TIME_STAMP if string is invalid
+time_t StringToTimestamp(std::string const & s);
+
+
+/// High resolution timer to use in comparison tests.
+using HighResTimer = impl::StdTimer<std::chrono::high_resolution_clock>;
+
+class ScopedTimerWithLog
+{
+public:
+  enum class Measure
+  {
+    MilliSeconds,
+    Seconds,
+  };
+
+  explicit ScopedTimerWithLog(std::string const & timerName,
+                              Measure measure = Measure::MilliSeconds);
+  ~ScopedTimerWithLog();
+
+private:
+  std::string m_name;
+  Measure m_measure;
+  HighResTimer m_timer;
+};
+
+time_t SecondsSinceEpochToTimeT(uint64_t secondsSinceEpoch);
+uint64_t TimeTToSecondsSinceEpoch(time_t time);
+}  // namespace base