Change SkTime::GetMSecs to double; ensure values stored in SkMSec do not overflow.

src/views/SkEvent.cpp

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkEvent.h"
@@ skipping 280 matching lines @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
 void SkEvent::postDelay(SkMSec delay) {
     if (!fTargetID && !fTargetProc) {
         delete this;
         return;
     }
 
     if (delay) {
-        this->postTime(SkTime::GetMSecs() + delay);
+        this->postTime(GetMSecsSinceStartup() + delay);
         return;
     }
 
     SkEvent_Globals& globals = getGlobals();
 
     globals.fEventMutex.acquire();
     bool wasEmpty = SkEvent::Enqueue(this);
     globals.fEventMutex.release();
 
     // call outside of us holding the mutex
@@ skipping 85 matching lines @@
     }
 
     evt->fTime = time;
     evt->fNextEvent = curr;
     if (prev == nullptr) {
         globals.fDelayQHead = evt;
     } else {
         prev->fNextEvent = evt;
     }
 
-    SkMSec delay = globals.fDelayQHead->fTime - SkTime::GetMSecs();
+    SkMSec delay = globals.fDelayQHead->fTime - GetMSecsSinceStartup();
     if ((int32_t)delay <= 0) {
         delay = 1;
     }
     return delay;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 #include "SkEventSink.h"
 
@@ skipping 11 matching lines @@
     return again;
 }
 
 void SkEvent::ServiceQueueTimer()
 {
     SkEvent_Globals& globals = getGlobals();
 
     globals.fEventMutex.acquire();
 
     bool        wasEmpty = false;
-    SkMSec      now = SkTime::GetMSecs();
+    SkMSec      now = GetMSecsSinceStartup();
     SkEvent*    evt = globals.fDelayQHead;
 
     while (evt)
     {
         if (SkMSec_LT(now, evt->fTime))
             break;
 
 #ifdef SK_TRACE_EVENTS
         --gDelayDepth;
         SkDebugf("dequeue-delay %s (%d)", evt->getType(), gDelayDepth);
@@ skipping 28 matching lines @@
     const SkEvent* evt = globals.fEventQHead;
     while (evt) {
         count += 1;
         evt = evt->fNextEvent;
     }
     globals.fEventMutex.release();
 
     return count;
 }
 
+SkMSec SkEvent::GetMSecsSinceStartup() {
+    static const double kEpoch = SkTime::GetMSecs();
+    return static_cast<SkMSec>(SkTime::GetMSecs() - kEpoch);
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 void SkEvent::Init() {}
 
 void SkEvent::Term() {
     SkEvent_Globals& globals = getGlobals();
 
     SkEvent* evt = globals.fEventQHead;
     while (evt) {
         SkEvent* next = evt->fNextEvent;
         delete evt;
         evt = next;
     }
 
     evt = globals.fDelayQHead;
     while (evt) {
         SkEvent* next = evt->fNextEvent;
         delete evt;
         evt = next;
     }
 }