diff options
| -rw-r--r-- | src/corelib/tools/qtimestamp_win.cpp | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/src/corelib/tools/qtimestamp_win.cpp b/src/corelib/tools/qtimestamp_win.cpp index 72d38d0..34bf7a7 100644 --- a/src/corelib/tools/qtimestamp_win.cpp +++ b/src/corelib/tools/qtimestamp_win.cpp @@ -76,6 +76,18 @@ static quint64 getTickCount() return GetTickCount(); } +static qint64 difference(qint64 a, qint64 b) +{ + qint64 retval = a - b; + // if we're not using GetTickCount64, then there can be 32-bit rollover + // assume there were rollovers if the difference is negative by more than + // 75% of the 32-bit range + + if (!ptrGetTickCount64 && retval < Q_INT64_C(-0xc0000000)) + retval += Q_UINT64_C(0x100000000); + return retval; +} + bool QTimestamp::isMonotonic() { return true; @@ -91,22 +103,26 @@ qint64 QTimestamp::restart() { qint64 oldt1 = t1; t1 = getTickCount(); - return t1 - oldt1; + return difference(t1, oldt1); } qint64 QTimestamp::elapsed() const { - return getTickCount() - t1; + return difference(getTickCount(), t1); } qint64 QTimestamp::msecsTo(const QTimestamp &other) const { - return other.t1 - t1; + return difference(other.t1, t1); } void QTimestamp::addMSecs(int ms) { t1 += ms; + + // do we need to simulate rolling over? + if (!ptrGetTickCount64) + t1 = quint32(t1); } qint64 QTimestamp::secsTo(const QTimestamp &other) const @@ -116,12 +132,12 @@ qint64 QTimestamp::secsTo(const QTimestamp &other) const void QTimestamp::addSecs(int secs) { - t1 += secs * 1000; + addMSecs(secs * 1000); } bool operator<(const QTimestamp &v1, const QTimestamp &v2) { - return v1.t1 < v2.t1; + return difference(v1.t1, v2.t1) < 0; } QT_END_NAMESPACE |