Bug 822490 - Radically simplify windows TimeStamp implementation, r=tellrob

ipc/glue/IPCMessageUtils.h

@@ -11,6 +11,9 @@
 #include "chrome/common/ipc_message_utils.h"
 
 #include "mozilla/TimeStamp.h"
+#ifdef XP_WIN
+#include "mozilla/TimeStamp_windows.h"
+#endif
 #include "mozilla/Util.h"
 #include "mozilla/gfx/2D.h"
 #include "mozilla/StandardInteger.h"
@@ -925,6 +928,30 @@ struct ParamTraits<mozilla::TimeStamp>
   };
 };
 
+#ifdef XP_WIN
+
+template<>
+struct ParamTraits<mozilla::TimeStampValue>
+{
+  typedef mozilla::TimeStampValue paramType;
+  static void Write(Message* aMsg, const paramType& aParam)
+  {
+    WriteParam(aMsg, aParam.mGTC);
+    WriteParam(aMsg, aParam.mQPC);
+    WriteParam(aMsg, aParam.mHasQPC);
+    WriteParam(aMsg, aParam.mIsNull);
+  }
+  static bool Read(const Message* aMsg, void** aIter, paramType* aResult)
+  {
+    return (ReadParam(aMsg, aIter, &aResult->mGTC) &&
+            ReadParam(aMsg, aIter, &aResult->mQPC) &&
+            ReadParam(aMsg, aIter, &aResult->mHasQPC) &&
+            ReadParam(aMsg, aIter, &aResult->mIsNull));
+  }
+};
+
+#endif
+
 template <>
 struct ParamTraits<mozilla::SerializedStructuredCloneBuffer>
 {

xpcom/ds/Makefile.in

@@ -59,6 +59,12 @@ EXPORTS_mozilla = \
   StringBuilder.h \
   $(NULL)
 
+ifeq ($(OS_ARCH),WINNT)
+EXPORTS_mozilla += \
+  TimeStamp_windows.h \
+  $(NULL)
+endif
+
 EXPORTS		= \
 		nsArray.h \
 		nsAtomService.h \

xpcom/ds/TimeStamp.h

@@ -16,8 +16,18 @@ namespace IPC {
 template <typename T> struct ParamTraits;
 }
 
+#ifdef XP_WIN
+// defines TimeStampValue as a complex value keeping both
+// GetTickCount and QueryPerformanceCounter values
+#include "TimeStamp_windows.h"
+#endif
+
 namespace mozilla {
 
+#ifndef XP_WIN
+typedef uint64_t TimeStampValue;
+#endif
+
 class TimeStamp;
 
 /**
@@ -150,7 +160,7 @@ private:
     return TimeDuration::FromTicks(int64_t(aTicks));
   }
 
-  // Duration in PRIntervalTime units
+  // Duration, result is implementation-specific difference of two TimeStamps
   int64_t mValue;
 };
 
@@ -286,7 +296,7 @@ public:
 private:
   friend struct IPC::ParamTraits<mozilla::TimeStamp>;
 
-  TimeStamp(uint64_t aValue) : mValue(aValue) {}
+  TimeStamp(TimeStampValue aValue) : mValue(aValue) {}
 
   /**
    * When built with PRIntervalTime, a value of 0 means this instance
@@ -301,7 +311,7 @@ private:
    *
    * When using a system clock, a value is system dependent.
    */
-  uint64_t mValue;
+  TimeStampValue mValue;
 };
 
 }

xpcom/ds/TimeStamp_windows.h

@@ -0,0 +1,58 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_TimeStamp_windows_h
+#define mozilla_TimeStamp_windows_h
+
+namespace mozilla {
+
+class TimeStamp;
+
+class TimeStampValue
+{
+  friend struct IPC::ParamTraits<mozilla::TimeStampValue>;
+  friend class TimeStamp;
+
+  // Both QPC and GTC are kept in [mt] units.
+  uint64_t mGTC;
+  uint64_t mQPC;
+  bool mHasQPC;
+  bool mIsNull;
+
+  TimeStampValue(uint64_t GTC, uint64_t QPC, bool hasQPC);
+
+  bool CheckQPC(int64_t aDuration, const TimeStampValue &aOther) const;
+
+public:
+  struct _SomethingVeryRandomHere;
+  TimeStampValue(_SomethingVeryRandomHere* nullValue);
+
+  uint64_t operator-(const TimeStampValue &aOther) const;
+
+  TimeStampValue operator+(const int64_t aOther) const
+    { return TimeStampValue(mGTC + aOther, mQPC + aOther, mHasQPC); }
+  TimeStampValue operator-(const int64_t aOther) const
+    { return TimeStampValue(mGTC - aOther, mQPC - aOther, mHasQPC); }
+  TimeStampValue& operator+=(const int64_t aOther);
+  TimeStampValue& operator-=(const int64_t aOther);
+
+  bool operator<(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) < 0; }
+  bool operator>(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) > 0; }
+  bool operator<=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) <= 0; }
+  bool operator>=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) >= 0; }
+  bool operator==(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) == 0; }
+  bool operator!=(const TimeStampValue &aOther) const
+    { return int64_t(*this - aOther) != 0; }
+};
+
+}
+
+#endif /* mozilla_TimeStamp_h */