Timer.cpp

//----------------------------------------------------------------------
// Includes
//----------------------------------------------------------------------
#include "MantidKernel/Timer.h"
#include <ostream>
#include <sstream>

namespace Mantid {
namespace Kernel {

/** Constructor.
 *  Instantiating the object starts the timer.
 */
Timer::Timer() {
#ifdef _WIN32
  m_start = clock();
#else /* linux & mac */
  gettimeofday(&m_start, 0);
#endif
}

/// Destructor
Timer::~Timer() {}

/** Returns the wall-clock time elapsed in seconds since the Timer object's
 *creation, or the last call to elapsed
 *
 * @param reset :: set to true to reset the clock (default)
 * @return time in seconds
 */
float Timer::elapsed(bool reset) {
  float retval = elapsed_no_reset();
  if (reset)
    this->reset();
  return retval;
}

/** Returns the wall-clock time elapsed in seconds since the Timer object's
 *creation, or the last call to elapsed
 *
 * @return time in seconds
 */
float Timer::elapsed_no_reset() const {
#ifdef _WIN32
  clock_t now = clock();
  const float retval = float(now - m_start) / CLOCKS_PER_SEC;
#else /* linux & mac */
  timeval now;
  gettimeofday(&now, 0);
  const float retval =
      float(now.tv_sec - m_start.tv_sec) +
      float(static_cast<float>(now.tv_usec - m_start.tv_usec) / 1e6);
#endif
  return retval;
}

/// Explicitly reset the timer.
void Timer::reset() {
#ifdef _WIN32
  m_start = clock();
#else /* linux & mac */
  timeval now;
  gettimeofday(&now, 0);
  m_start = now;
#endif
}

/// Convert the elapsed time (without reseting) to a string.
std::string Timer::str() const {
  std::stringstream buffer;
  buffer << this->elapsed_no_reset() << "s";
  return buffer.str();
}

/// Convenience function to provide for easier debug printing.
std::ostream &operator<<(std::ostream &out, const Timer &obj) {
  out << obj.str();
  return out;
}

} // namespace Kernel
} // namespace Mantid