Merge pull request #1070 from majestrate/monotonic-time-2020-01-23

make all timestamps monotonic and run loopback testnet at 1/5 speed

CMakeLists.txt

@@ -195,6 +195,8 @@ endif(USE_NETNS)
 
 if(TESTNET)
   add_definitions(-DTESTNET=1)
+  # 5 times slower than realtime
+  add_definitions(-DTESTNET_SPEED=5)
 endif(TESTNET)
 
 if(SHADOW)

llarp/ev/ev_libuv.cpp

@@ -836,6 +836,9 @@ namespace libuv
   {
     if(m_Run)
     {
+#ifdef TESTNET_SPEED
+      ms *= TESTNET_SPEED;
+#endif
       uv_timer_start(m_TickTimer, &OnTickTimeout, ms, 0);
       uv_run(&m_Impl, UV_RUN_ONCE);
     }
@@ -872,6 +875,9 @@ namespace libuv
   Loop::call_after_delay(llarp_time_t delay_ms,
                          std::function< void(void) > callback)
   {
+#ifdef TESTNET_SPEED
+    delay_ms *= TESTNET_SPEED;
+#endif
     PendingTimer timer;
     timer.delay_ms  = delay_ms;
     timer.callback  = callback;

llarp/util/time.cpp

@@ -6,24 +6,39 @@ namespace llarp
 {
   using Clock_t = std::chrono::system_clock;
 
-  template < typename Res >
+  template < typename Res, typename Clock >
   static llarp_time_t
   time_since_epoch()
   {
-    return std::chrono::duration_cast< Res >(
+    return std::chrono::duration_cast< Res >(Clock::now().time_since_epoch())
-               llarp::Clock_t::now().time_since_epoch())
         .count();
   }
 
-  // use std::chrono because otherwise the network breaks with Daylight Savings
+  const static llarp_time_t started_at_system =
-  // this time, it doesn't get truncated -despair
+      time_since_epoch< std::chrono::milliseconds, Clock_t >();
-  // that concern is what drove me back to the POSIX C time functions
+
-  // in the first place
+  const static llarp_time_t started_at_steady =
+      time_since_epoch< std::chrono::milliseconds,
+                        std::chrono::steady_clock >();
+  /// get our uptime in ms
+  static llarp_time_t
+  time_since_started()
+  {
+    return time_since_epoch< std::chrono::milliseconds,
+                             std::chrono::steady_clock >()
+        - started_at_steady;
+  }
+
   llarp_time_t
   time_now_ms()
   {
     static llarp_time_t lastTime = 0;
-    auto t = llarp::time_since_epoch< std::chrono::milliseconds >();
+    auto t                       = time_since_started();
+#ifdef TESTNET_SPEED
+    t /= TESTNET_SPEED;
+#endif
+    t += started_at_system;
+
     if(t <= lastTime)
     {
       return lastTime;

llarp/util/time.hpp

@@ -5,6 +5,7 @@
 
 namespace llarp
 {
+  /// get time right now as milliseconds, this is monotonic
   llarp_time_t
   time_now_ms();
 }  // namespace llarp