duration.cpp

00001 /*
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00034 
00035 #include <math.h>
00036 #include "ros/duration.h"
00037 
00038 namespace ros
00039 {
00040 void normalizeSecNSecSigned(int32_t &sec, int32_t &nsec)
00041 {
00042   int32_t nsec_part = nsec;
00043   int32_t sec_part = sec;
00044 
00045   while (nsec_part > 1000000000L)
00046   {
00047     nsec_part -= 1000000000L;
00048     ++sec_part;
00049   }
00050   while (nsec_part < 0)
00051   {
00052     nsec_part += 1000000000L;
00053     --sec_part;
00054   }
00055   sec = sec_part;
00056   nsec = nsec_part;
00057 }
00058 
00059 Duration& Duration::operator+=(const Duration &rhs)
00060 {
00061   sec += rhs.sec;
00062   nsec += rhs.nsec;
00063   normalizeSecNSecSigned(sec, nsec);
00064   return *this;
00065 }
00066 
00067 Duration& Duration::operator-=(const Duration &rhs)
00068 {
00069   sec += -rhs.sec;
00070   nsec += -rhs.nsec;
00071   normalizeSecNSecSigned(sec, nsec);
00072   return *this;
00073 }
00074 
00075 Duration& Duration::operator*=(double scale)
00076 {
00077   sec *= scale;
00078   nsec *= scale;
00079   normalizeSecNSecSigned(sec, nsec);
00080   return *this;
00081 }
00082 
00083 }