Diff: hdtimeval_math.cpp

Revision:

0:b9f06a7ae791

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hdtimeval_math.cpp	Fri Dec 03 20:53:21 2010 +0000
@@ -0,0 +1,67 @@
+#include "hdtimeval_math.h"
+
+void hdtv_add (hdtimeval_t * r, hdtimeval_t * v1, hdtimeval_t * v2)
+{
+    r->tv_sec = v1->tv_sec + v2->tv_sec;
+    r->ticks = v1->ticks + v2->ticks;
+    if (r->ticks >= MAX_TICK) {
+        r->tv_sec++;
+        r->ticks -= MAX_TICK;
+    }
+}
+
+void hdtv_div2 (hdtimeval_t * r, hdtimeval_t * v)
+{
+    if (v->tv_sec & 0x1) {
+        r->ticks = ((v->ticks+MAX_TICK)>>1);
+    } else {
+        r->ticks = (v->ticks>>1);
+    }
+    r->tv_sec = (v->tv_sec>>1);
+}
+
+void hdtv_div8 (hdtimeval_t * r, hdtimeval_t * v)
+{
+    r->ticks = ((v->ticks+MAX_TICK*(v->tv_sec & 0x7))>>3);
+    r->tv_sec = (v->tv_sec>>3);
+}
+
+void hdtv_sub (hdtimeval_t * r, hdtimeval_t * v1, hdtimeval_t * v2)
+{
+    r->tv_sec = v1->tv_sec - v2->tv_sec;
+    if (v1->ticks < v2->ticks) {
+        r->ticks = MAX_TICK + v1->ticks - v2->ticks;
+        r->tv_sec --;
+    } else {
+        r->ticks = v1->ticks - v2->ticks;
+    }
+}
+
+void hdtv_muldiv (hdtimeval_t * r, hdtimeval_t * v, hdtimeval_t * m, hdtimeval_t * d)
+{
+    double dblm, dbld, factor, rsec, rticks;
+    uint32_t irticks, c;
+    int32_t irsec;
+
+    dblm = (double)(m->tv_sec) * (double)MAX_TICK + (double)(m->ticks);
+    dbld = (double)(d->tv_sec) * (double)MAX_TICK + (double)(d->ticks);
+    factor = dblm / dbld;
+    
+    rsec = (double)(v->tv_sec) * factor;
+    rticks = (double)(v->ticks) * factor + (rsec - floor(rsec)) * (double)MAX_TICK;
+    irticks = (uint32_t)rticks;
+    irsec = (int32_t)rsec;
+    c = irticks / MAX_TICK;
+    r->tv_sec = irsec + c;
+    r->ticks = irticks - c * MAX_TICK;
+}
+
+void hdtv_totv(timeval_t * r, hdtimeval_t * v)
+{
+    r->tv_sec = v->tv_sec;
+    r->tv_usec = (v->ticks + 48)/96;
+    if (r->tv_usec >= 1000000) {
+        r->tv_sec ++;
+        r->tv_usec -= 1000000;
+    }
+}