QtMiscUtils: add std::chrono::duration <-> timespec helpers

Change-Id: I91f36a3d651fd57443072fde4c3e8f811682328e
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qfilesystemengine_unix.cpp

@@ -12,6 +12,7 @@
 #include <QtCore/qoperatingsystemversion.h>
 #include <QtCore/private/qcore_unix_p.h>
 #include <QtCore/private/qfiledevice_p.h>
+#include <QtCore/private/qtools_p.h>
 #include <QtCore/qvarlengtharray.h>
 #ifndef QT_BOOTSTRAPPED
 # include <QtCore/qstandardpaths.h>
@@ -1556,13 +1557,9 @@ bool QFileSystemEngine::setFileTime(int fd, const QDateTime &newDate, QAbstractF
     struct timespec ts[2] = {{0, UTIME_OMIT}, {0, UTIME_OMIT}};
 
     if (time == QAbstractFileEngine::AccessTime || time == QAbstractFileEngine::ModificationTime) {
-        using namespace std::chrono;
-        const milliseconds msecs{newDate.toMSecsSinceEpoch()};
-        const seconds secs = duration_cast<seconds>(msecs);
-        const nanoseconds frac = msecs - secs;
         const int idx = time == QAbstractFileEngine::AccessTime ? 0 : 1;
-        ts[idx].tv_sec = secs.count();
-        ts[idx].tv_nsec = frac.count();
+        const std::chrono::milliseconds msecs{newDate.toMSecsSinceEpoch()};
+        ts[idx] = QtMiscUtils::durationToTimespec(msecs);
     }
 
     if (futimens(fd, ts) == -1) {

src/corelib/kernel/qtimerinfo_unix.cpp

@@ -9,6 +9,7 @@
 #include "private/qtimerinfo_unix_p.h"
 #include "private/qobject_p.h"
 #include "private/qabstracteventdispatcher_p.h"
+#include <QtCore/private/qtools_p.h>
 
 #ifdef QTIMERINFO_DEBUG
 #  include <QDebug>
@@ -396,8 +397,7 @@ qint64 QTimerInfoList::timerRemainingTime(int timerId)
             if (currentTime < t->timeout) {
                 // time to wait
                 tm = roundToMillisecond(t->timeout - currentTime);
-                using namespace std::chrono;
-                const auto dur = duration_cast<milliseconds>(seconds{tm.tv_sec} + nanoseconds{tm.tv_nsec});
+                const std::chrono::milliseconds dur = QtMiscUtils::timespecToChronoMs(&tm);
                 return dur.count();
             } else {
                 return 0;

src/corelib/thread/qthread_unix.cpp

@@ -8,6 +8,7 @@
 
 #include <private/qcoreapplication_p.h>
 #include <private/qcore_unix_p.h>
+#include <private/qtools_p.h>
 
 #if defined(Q_OS_DARWIN)
 #  include <private/qeventdispatcher_cf_p.h>
@@ -70,6 +71,8 @@
 
 QT_BEGIN_NAMESPACE
 
+using namespace QtMiscUtils;
+
 #if QT_CONFIG(thread)
 
 static_assert(sizeof(pthread_t) <= sizeof(Qt::HANDLE));
@@ -488,31 +491,19 @@ void QThread::yieldCurrentThread()
 
 #endif // QT_CONFIG(thread)
 
-static timespec makeTimespec(std::chrono::nanoseconds nsecs)
-{
-    using namespace std::chrono;
-    const seconds secs = duration_cast<seconds>(nsecs);
-    const nanoseconds frac = nsecs - secs;
-    struct timespec ts;
-    ts.tv_sec = secs.count();
-    ts.tv_nsec = frac.count();
-    return ts;
-}
-
-
 void QThread::sleep(unsigned long secs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::seconds{secs}));
+    qt_nanosleep(durationToTimespec(std::chrono::seconds{secs}));
 }
 
 void QThread::msleep(unsigned long msecs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::milliseconds{msecs}));
+    qt_nanosleep(durationToTimespec(std::chrono::milliseconds{msecs}));
 }
 
 void QThread::usleep(unsigned long usecs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::microseconds{usecs}));
+    qt_nanosleep(durationToTimespec(std::chrono::microseconds{usecs}));
 }
 
 #if QT_CONFIG(thread)

src/corelib/tools/qtools_p.h

@@ -16,7 +16,10 @@
 //
 
 #include "QtCore/private/qglobal_p.h"
+
+#include <chrono>
 #include <limits.h>
+#include <time.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -104,8 +107,32 @@ constexpr inline int qt_lencmp(qsizetype lhs, qsizetype rhs) noexcept
            lhs >  rhs ? 1 :
            /* else */  -1 ;
 }
+
+inline timespec durationToTimespec(std::chrono::nanoseconds timeout) noexcept
+{
+    using namespace std::chrono;
+    const seconds secs = duration_cast<seconds>(timeout);
+    const nanoseconds frac = timeout - secs;
+    struct timespec ts;
+    ts.tv_sec = secs.count();
+    ts.tv_nsec = frac.count();
+    return ts;
 }
 
+template <typename Duration>
+inline Duration timespecToChrono(struct timespec *ts) noexcept
+{
+    using namespace std::chrono;
+    return duration_cast<Duration>(seconds{ts->tv_sec} + nanoseconds{ts->tv_nsec});
+}
+
+inline std::chrono::milliseconds timespecToChronoMs(struct timespec *ts) noexcept
+{
+    return timespecToChrono<std::chrono::milliseconds>(ts);
+}
+
+} // namespace QtMiscUtils
+
 // We typically need an extra bit for qNextPowerOfTwo when determining the next allocation size.
 constexpr qsizetype MaxAllocSize = (std::numeric_limits<qsizetype>::max)();