time.cpp

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#include "ros/time.h"
 
namespace ros
{
void normalizeSecNSec(uint32_t& sec, uint32_t& nsec)
{
  uint32_t nsec_part = nsec % 1000000000UL;
  uint32_t sec_part = nsec / 1000000000UL;
  sec += sec_part;
  nsec = nsec_part;
}
 
Time& Time::fromNSec(int32_t t)
{
  sec = t / 1000000000;
  nsec = t % 1000000000;
  normalizeSecNSec(sec, nsec);
  return *this;
}
 
Time& Time::operator +=(const Duration &rhs)
{
  sec = sec - 1 + rhs.sec;
  nsec = nsec + 1000000000UL + rhs.nsec;
  normalizeSecNSec(sec, nsec);
  return *this;
}
 
Time& Time::operator -=(const Duration &rhs){
  sec = sec - 1 - rhs.sec;
  nsec = nsec + 1000000000UL - rhs.nsec;
  normalizeSecNSec(sec, nsec);
  return *this;
}
 
Duration Time::operator-(const Time &rhs) const {
  // Note: Considers wrap around as a continuation of time, e.g.,
  // (0,0) - (0xFFFFFFFF, 0) = (1, 0)
  Duration d;
  d.sec = sec > rhs.sec ? sec - rhs.sec : -(rhs.sec - sec);
  d.nsec = nsec > rhs.nsec ? nsec - rhs.nsec : -(rhs.nsec - nsec);
  normalizeSecNSecSigned(d.sec, d.nsec);
  return d;
}
}