Converted PhasedLoop over to monotonic_clock.

Change-Id: Ic8857c4412abb7c19dd3df4aaa5f6c8aa74e9dc6
diff --git a/aos/common/util/phased_loop.cc b/aos/common/util/phased_loop.cc
index b5804c8..9c81ffb 100644
--- a/aos/common/util/phased_loop.cc
+++ b/aos/common/util/phased_loop.cc
@@ -10,15 +10,21 @@
              frequency + Time::InUS(offset));
 }
 
-int PhasedLoop::Iterate(const Time &now) {
-  const Time next_time = Time::InNS(((now - offset_).ToNSec() + 1) /
-                                    interval_.ToNSec() * interval_.ToNSec()) +
-                         ((now < offset_) ? Time::kZero : interval_) + offset_;
+int PhasedLoop::Iterate(const monotonic_clock::time_point now) {
+  const monotonic_clock::time_point next_time =
+      monotonic_clock::time_point(
+          (((now - offset_).time_since_epoch() + monotonic_clock::duration(1)) /
+           interval_) *
+          interval_) +
+      ((now.time_since_epoch() < offset_) ? monotonic_clock::zero()
+                                          : interval_) +
+      offset_;
 
-  const Time difference = next_time - last_time_;
-  const int result = difference.ToNSec() / interval_.ToNSec();
+  const monotonic_clock::duration difference = next_time - last_time_;
+  const int result = difference / interval_;
   CHECK_EQ(difference, interval_ * result);
-  CHECK_EQ(0, (next_time - offset_).ToNSec() % interval_.ToNSec());
+  CHECK_EQ(
+      0, (next_time - offset_).time_since_epoch().count() % interval_.count());
   CHECK_GE(next_time, now);
   CHECK_LE(next_time - now, interval_);
   last_time_ = next_time;
diff --git a/aos/common/util/phased_loop.h b/aos/common/util/phased_loop.h
index fc0f247..7614ed2 100644
--- a/aos/common/util/phased_loop.h
+++ b/aos/common/util/phased_loop.h
@@ -22,40 +22,47 @@
   //   ...
   //   10000.1s
   // offset must be >= Time::kZero and < interval.
-  PhasedLoop(const Time &interval, const Time &offset = Time::kZero)
+  PhasedLoop(
+      const monotonic_clock::duration interval,
+      const monotonic_clock::duration offset = monotonic_clock::duration(0))
       : interval_(interval), offset_(offset), last_time_(offset) {
-    CHECK_GE(offset, Time::kZero);
-    CHECK_GT(interval, Time::kZero);
+    CHECK_GE(offset, monotonic_clock::duration(0));
+    CHECK_GT(interval, monotonic_clock::duration(0));
     CHECK_LT(offset, interval);
     Reset();
   }
 
   // Resets the count of skipped iterations.
-  // Iterate(now) will return 1 and set sleep_time() to something within
-  // interval of now.
-  void Reset(const Time &now = Time::Now()) { Iterate(now - interval_); }
+  // Iterate(monotonic_now) will return 1 and set sleep_time() to something
+  // within interval of monotonic_now.
+  void Reset(const monotonic_clock::time_point monotonic_now =
+                 monotonic_clock::now()) {
+    Iterate(monotonic_now - interval_);
+  }
 
-  // Calculates the next time to run after now.
+  // Calculates the next time to run after monotonic_now.
   // The result can be retrieved with sleep_time().
   // Returns the number of iterations which have passed (1 if this is called
-  // often enough). This can be < 1 iff now goes backwards between calls.
-  int Iterate(const Time &now = Time::Now());
+  // often enough). This can be < 1 iff monotonic_now goes backwards between
+  // calls.
+  int Iterate(const monotonic_clock::time_point monotonic_now =
+                  monotonic_clock::now());
 
   // Sleeps until the next time and returns the number of iterations which have
   // passed.
   int SleepUntilNext() {
-    const int r = Iterate(Time::Now());
-    SleepUntil(sleep_time());
+    const int r = Iterate(monotonic_clock::now());
+    ::std::this_thread::sleep_until(sleep_time());
     return r;
   }
 
-  const Time &sleep_time() const { return last_time_; }
+  monotonic_clock::time_point sleep_time() const { return last_time_; }
 
  private:
-  const Time interval_, offset_;
+  const monotonic_clock::duration interval_, offset_;
 
   // The time we most recently slept until.
-  Time last_time_ = Time::kZero;
+  monotonic_clock::time_point last_time_ = monotonic_clock::epoch();
 };
 
 }  // namespace time
diff --git a/aos/common/util/phased_loop_test.cc b/aos/common/util/phased_loop_test.cc
index 1641a92..b013c2e 100644
--- a/aos/common/util/phased_loop_test.cc
+++ b/aos/common/util/phased_loop_test.cc
@@ -8,111 +8,115 @@
 namespace time {
 namespace testing {
 
+using ::std::chrono::milliseconds;
+
 class PhasedLoopTest : public ::testing::Test {
  protected:
-  PhasedLoopTest() {
-    ::aos::testing::EnableTestLogging();
-  }
+  PhasedLoopTest() { ::aos::testing::EnableTestLogging(); }
 };
 
 typedef PhasedLoopTest PhasedLoopDeathTest;
 
+monotonic_clock::time_point InMs(int ms) {
+  return monotonic_clock::time_point(::std::chrono::milliseconds(ms));
+}
+
 TEST_F(PhasedLoopTest, Reset) {
   {
-    PhasedLoop loop(Time::InMS(100), Time::kZero);
+    PhasedLoop loop(milliseconds(100), milliseconds(0));
 
-    loop.Reset(Time::kZero);
-    EXPECT_EQ(Time::InMS(0), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::kZero));
-    EXPECT_EQ(Time::InMS(100), loop.sleep_time());
+    loop.Reset(monotonic_clock::epoch());
+    EXPECT_EQ(InMs(0), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(monotonic_clock::epoch()));
+    EXPECT_EQ(InMs(100), loop.sleep_time());
 
-    loop.Reset(Time::InMS(99));
-    EXPECT_EQ(Time::InMS(0), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(99)));
-    EXPECT_EQ(Time::InMS(100), loop.sleep_time());
+    loop.Reset(InMs(99));
+    EXPECT_EQ(InMs(0), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(99)));
+    EXPECT_EQ(InMs(100), loop.sleep_time());
 
-    loop.Reset(Time::InMS(100));
-    EXPECT_EQ(Time::InMS(100), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(199)));
-    EXPECT_EQ(Time::InMS(200), loop.sleep_time());
+    loop.Reset(InMs(100));
+    EXPECT_EQ(InMs(100), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(199)));
+    EXPECT_EQ(InMs(200), loop.sleep_time());
 
-    loop.Reset(Time::InMS(101));
-    EXPECT_EQ(Time::InMS(100), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(101)));
-    EXPECT_EQ(Time::InMS(200), loop.sleep_time());
+    loop.Reset(InMs(101));
+    EXPECT_EQ(InMs(100), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(101)));
+    EXPECT_EQ(InMs(200), loop.sleep_time());
   }
   {
-    PhasedLoop loop(Time::InMS(100), Time::InMS(1));
-    loop.Reset(Time::kZero);
-    EXPECT_EQ(Time::InMS(-99), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::kZero));
-    EXPECT_EQ(Time::InMS(1), loop.sleep_time());
+    PhasedLoop loop(milliseconds(100), milliseconds(1));
+    loop.Reset(monotonic_clock::epoch());
+    EXPECT_EQ(InMs(-99), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(monotonic_clock::epoch()));
+    EXPECT_EQ(InMs(1), loop.sleep_time());
   }
   {
-    PhasedLoop loop(Time::InMS(100), Time::InMS(99));
+    PhasedLoop loop(milliseconds(100), milliseconds(99));
 
-    loop.Reset(Time::kZero);
-    EXPECT_EQ(Time::InMS(-1), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::kZero));
-    EXPECT_EQ(Time::InMS(99), loop.sleep_time());
+    loop.Reset(monotonic_clock::epoch());
+    EXPECT_EQ(InMs(-1), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(monotonic_clock::epoch()));
+    EXPECT_EQ(InMs(99), loop.sleep_time());
 
-    loop.Reset(Time::InMS(98));
-    EXPECT_EQ(Time::InMS(-1), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(98)));
-    EXPECT_EQ(Time::InMS(99), loop.sleep_time());
+    loop.Reset(InMs(98));
+    EXPECT_EQ(InMs(-1), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(98)));
+    EXPECT_EQ(InMs(99), loop.sleep_time());
 
-    loop.Reset(Time::InMS(99));
-    EXPECT_EQ(Time::InMS(99), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(99)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
+    loop.Reset(InMs(99));
+    EXPECT_EQ(InMs(99), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(99)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
 
-    loop.Reset(Time::InMS(100));
-    EXPECT_EQ(Time::InMS(99), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(100)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
+    loop.Reset(InMs(100));
+    EXPECT_EQ(InMs(99), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(100)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
   }
 }
 
 TEST_F(PhasedLoopTest, Iterate) {
   {
-    PhasedLoop loop(Time::InMS(100), Time::InMS(99));
-    loop.Reset(Time::kZero);
-    EXPECT_EQ(1, loop.Iterate(Time::kZero));
-    EXPECT_EQ(Time::InMS(99), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(100)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(100)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(101)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(198)));
-    EXPECT_EQ(Time::InMS(199), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(199)));
-    EXPECT_EQ(Time::InMS(299), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(300)));
-    EXPECT_EQ(Time::InMS(399), loop.sleep_time());
-    EXPECT_EQ(3, loop.Iterate(Time::InMS(600)));
-    EXPECT_EQ(Time::InMS(699), loop.sleep_time());
+    PhasedLoop loop(milliseconds(100), milliseconds(99));
+    loop.Reset(monotonic_clock::epoch());
+    EXPECT_EQ(1, loop.Iterate(monotonic_clock::epoch()));
+    EXPECT_EQ(InMs(99), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(100)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(100)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(101)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(198)));
+    EXPECT_EQ(InMs(199), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(199)));
+    EXPECT_EQ(InMs(299), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(300)));
+    EXPECT_EQ(InMs(399), loop.sleep_time());
+    EXPECT_EQ(3, loop.Iterate(InMs(600)));
+    EXPECT_EQ(InMs(699), loop.sleep_time());
   }
   {
-    PhasedLoop loop(Time::InMS(100), Time::InMS(1));
-    loop.Reset(Time::kZero);
-    EXPECT_EQ(1, loop.Iterate(Time::kZero));
-    EXPECT_EQ(Time::InMS(1), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(100)));
-    EXPECT_EQ(Time::InMS(101), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(100)));
-    EXPECT_EQ(Time::InMS(101), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(103)));
-    EXPECT_EQ(Time::InMS(201), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(198)));
-    EXPECT_EQ(Time::InMS(201), loop.sleep_time());
-    EXPECT_EQ(0, loop.Iterate(Time::InMS(200)));
-    EXPECT_EQ(Time::InMS(201), loop.sleep_time());
-    EXPECT_EQ(1, loop.Iterate(Time::InMS(201)));
-    EXPECT_EQ(Time::InMS(301), loop.sleep_time());
-    EXPECT_EQ(3, loop.Iterate(Time::InMS(600)));
-    EXPECT_EQ(Time::InMS(601), loop.sleep_time());
+    PhasedLoop loop(milliseconds(100), milliseconds(1));
+    loop.Reset(monotonic_clock::epoch());
+    EXPECT_EQ(1, loop.Iterate(monotonic_clock::epoch()));
+    EXPECT_EQ(InMs(1), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(100)));
+    EXPECT_EQ(InMs(101), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(100)));
+    EXPECT_EQ(InMs(101), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(103)));
+    EXPECT_EQ(InMs(201), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(198)));
+    EXPECT_EQ(InMs(201), loop.sleep_time());
+    EXPECT_EQ(0, loop.Iterate(InMs(200)));
+    EXPECT_EQ(InMs(201), loop.sleep_time());
+    EXPECT_EQ(1, loop.Iterate(InMs(201)));
+    EXPECT_EQ(InMs(301), loop.sleep_time());
+    EXPECT_EQ(3, loop.Iterate(InMs(600)));
+    EXPECT_EQ(InMs(601), loop.sleep_time());
   }
 }
 
@@ -120,40 +124,42 @@
 // This seems like a rare case at first, but starting from zero needs to
 // work, which means negatives should too.
 TEST_F(PhasedLoopTest, CrossingZero) {
-  PhasedLoop loop(Time::InMS(100), Time::InMS(1));
-  loop.Reset(Time::InMS(-1000));
-  EXPECT_EQ(Time::InMS(-1099), loop.sleep_time());
-  EXPECT_EQ(9, loop.Iterate(Time::InMS(-250)));
-  EXPECT_EQ(Time::InMS(-199), loop.sleep_time());
-  EXPECT_EQ(1, loop.Iterate(Time::InMS(-199)));
-  EXPECT_EQ(Time::InMS(-99), loop.sleep_time());
-  EXPECT_EQ(1, loop.Iterate(Time::InMS(-90)));
-  EXPECT_EQ(Time::InMS(1), loop.sleep_time());
-  EXPECT_EQ(0, loop.Iterate(Time::InMS(0)));
-  EXPECT_EQ(Time::InMS(1), loop.sleep_time());
-  EXPECT_EQ(1, loop.Iterate(Time::InMS(1)));
-  EXPECT_EQ(Time::InMS(101), loop.sleep_time());
+  PhasedLoop loop(milliseconds(100), milliseconds(1));
+  loop.Reset(InMs(-1000));
+  EXPECT_EQ(InMs(-1099), loop.sleep_time());
+  EXPECT_EQ(9, loop.Iterate(InMs(-250)));
+  EXPECT_EQ(InMs(-199), loop.sleep_time());
+  EXPECT_EQ(1, loop.Iterate(InMs(-199)));
+  EXPECT_EQ(InMs(-99), loop.sleep_time());
+  EXPECT_EQ(1, loop.Iterate(InMs(-90)));
+  EXPECT_EQ(InMs(1), loop.sleep_time());
+  EXPECT_EQ(0, loop.Iterate(InMs(0)));
+  EXPECT_EQ(InMs(1), loop.sleep_time());
+  EXPECT_EQ(1, loop.Iterate(InMs(1)));
+  EXPECT_EQ(InMs(101), loop.sleep_time());
 
-  EXPECT_EQ(0, loop.Iterate(Time::InMS(2)));
-  EXPECT_EQ(Time::InMS(101), loop.sleep_time());
+  EXPECT_EQ(0, loop.Iterate(InMs(2)));
+  EXPECT_EQ(InMs(101), loop.sleep_time());
 
-  EXPECT_EQ(-2, loop.Iterate(Time::InMS(-101)));
-  EXPECT_EQ(Time::InMS(-99), loop.sleep_time());
-  EXPECT_EQ(1, loop.Iterate(Time::InMS(-99)));
-  EXPECT_EQ(Time::InMS(1), loop.sleep_time());
+  EXPECT_EQ(-2, loop.Iterate(InMs(-101)));
+  EXPECT_EQ(InMs(-99), loop.sleep_time());
+  EXPECT_EQ(1, loop.Iterate(InMs(-99)));
+  EXPECT_EQ(InMs(1), loop.sleep_time());
 
-  EXPECT_EQ(0, loop.Iterate(Time::InMS(-99)));
-  EXPECT_EQ(Time::InMS(1), loop.sleep_time());
+  EXPECT_EQ(0, loop.Iterate(InMs(-99)));
+  EXPECT_EQ(InMs(1), loop.sleep_time());
 }
 
 // Tests that passing invalid values to the constructor dies correctly.
 TEST_F(PhasedLoopDeathTest, InvalidValues) {
-  EXPECT_DEATH(PhasedLoop(Time::InMS(1), Time::InMS(2)), ".*offset<interval.*");
-  EXPECT_DEATH(PhasedLoop(Time::InMS(1), Time::InMS(1)), ".*offset<interval.*");
-  EXPECT_DEATH(PhasedLoop(Time::InMS(1), Time::InMS(-1)),
-               ".*offset>=Time::kZero.*");
-  EXPECT_DEATH(PhasedLoop(Time::InMS(0), Time::InMS(0)),
-               ".*interval>Time::kZero.*");
+  EXPECT_DEATH(PhasedLoop(milliseconds(1), milliseconds(2)),
+               ".*offset<interval.*");
+  EXPECT_DEATH(PhasedLoop(milliseconds(1), milliseconds(1)),
+               ".*offset<interval.*");
+  EXPECT_DEATH(PhasedLoop(milliseconds(1), milliseconds(-1)),
+               ".*offset>=monotonic_clock::duration\\(0\\).*");
+  EXPECT_DEATH(PhasedLoop(milliseconds(0), milliseconds(0)),
+               ".*interval>monotonic_clock::duration\\(0\\).*");
 }
 
 }  // namespace testing