1 files changed, 549 insertions, 123 deletions

diff --git a/Python/pytime.c b/Python/pytime.c
index de6a41fe00..02a93749c7 100644
--- a/Python/pytime.c
+++ b/Python/pytime.c
@@ -3,115 +3,25 @@
 #include <windows.h>
 #endif
 
-#if defined(__APPLE__) && defined(HAVE_GETTIMEOFDAY) && defined(HAVE_FTIME)
-  /*
-   * _PyTime_gettimeofday falls back to ftime when getttimeofday fails because the latter
-   * might fail on some platforms. This fallback is unwanted on MacOSX because
-   * that makes it impossible to use a binary build on OSX 10.4 on earlier
-   * releases of the OS. Therefore claim we don't support ftime.
-   */
-# undef HAVE_FTIME
+#if defined(__APPLE__)
+#include <mach/mach_time.h>   /* mach_absolute_time(), mach_timebase_info() */
 #endif
 
-#if defined(HAVE_FTIME) && !defined(MS_WINDOWS)
-#include <sys/timeb.h>
-extern int ftime(struct timeb *);
-#endif
+/* To millisecond (10^-3) */
+#define SEC_TO_MS 1000
 
-static void
-pygettimeofday(_PyTime_timeval *tp, _Py_clock_info_t *info)
-{
-#ifdef MS_WINDOWS
-    FILETIME system_time;
-    ULARGE_INTEGER large;
-    ULONGLONG microseconds;
+/* To microseconds (10^-6) */
+#define MS_TO_US 1000
+#define SEC_TO_US (SEC_TO_MS * MS_TO_US)
 
-    GetSystemTimeAsFileTime(&system_time);
-    large.u.LowPart = system_time.dwLowDateTime;
-    large.u.HighPart = system_time.dwHighDateTime;
-    /* 11,644,473,600,000,000: number of microseconds between
-       the 1st january 1601 and the 1st january 1970 (369 years + 89 leap
-       days). */
-    microseconds = large.QuadPart / 10 - 11644473600000000;
-    tp->tv_sec = microseconds / 1000000;
-    tp->tv_usec = microseconds % 1000000;
-    if (info) {
-        DWORD timeAdjustment, timeIncrement;
-        BOOL isTimeAdjustmentDisabled;
+/* To nanoseconds (10^-9) */
+#define US_TO_NS 1000
+#define MS_TO_NS (MS_TO_US * US_TO_NS)
+#define SEC_TO_NS (SEC_TO_MS * MS_TO_NS)
 
-        info->implementation = "GetSystemTimeAsFileTime()";
-        info->monotonic = 0;
-        (void) GetSystemTimeAdjustment(&timeAdjustment, &timeIncrement,
-                                       &isTimeAdjustmentDisabled);
-        info->resolution = timeIncrement * 1e-7;
-        info->adjustable = 1;
-    }
-#else
-    /* There are three ways to get the time:
-      (1) gettimeofday() -- resolution in microseconds
-      (2) ftime() -- resolution in milliseconds
-      (3) time() -- resolution in seconds
-      In all cases the return value in a timeval struct.
-      Since on some systems (e.g. SCO ODT 3.0) gettimeofday() may
-      fail, so we fall back on ftime() or time().
-      Note: clock resolution does not imply clock accuracy! */
-
-#ifdef HAVE_GETTIMEOFDAY
-    int err;
-#ifdef GETTIMEOFDAY_NO_TZ
-    err = gettimeofday(tp);
-#else
-    err = gettimeofday(tp, (struct timezone *)NULL);
-#endif
-    if (err == 0) {
-        if (info) {
-            info->implementation = "gettimeofday()";
-            info->resolution = 1e-6;
-            info->monotonic = 0;
-            info->adjustable = 1;
-        }
-        return;
-    }
-#endif   /* HAVE_GETTIMEOFDAY */
-
-#if defined(HAVE_FTIME)
-    {
-        struct timeb t;
-        ftime(&t);
-        tp->tv_sec = t.time;
-        tp->tv_usec = t.millitm * 1000;
-        if (info) {
-            info->implementation = "ftime()";
-            info->resolution = 1e-3;
-            info->monotonic = 0;
-            info->adjustable = 1;
-        }
-    }
-#else /* !HAVE_FTIME */
-    tp->tv_sec = time(NULL);
-    tp->tv_usec = 0;
-    if (info) {
-        info->implementation = "time()";
-        info->resolution = 1.0;
-        info->monotonic = 0;
-        info->adjustable = 1;
-    }
-#endif /* !HAVE_FTIME */
-
-#endif /* MS_WINDOWS */
-}
-
-void
-_PyTime_gettimeofday(_PyTime_timeval *tp)
-{
-    pygettimeofday(tp, NULL);
-}
-
-void
-_PyTime_gettimeofday_info(_PyTime_timeval *tp, _Py_clock_info_t *info)
-{
-    pygettimeofday(tp, info);
-}
+/* Conversion from nanoseconds */
+#define NS_TO_MS (1000 * 1000)
+#define NS_TO_US (1000)
 
 static void
 error_time_t_overflow(void)
@@ -168,18 +78,16 @@ _PyTime_ObjectToDenominator(PyObject *obj, time_t *sec, long *numerator,
         }
 
         floatpart *= denominator;
-        if (round == _PyTime_ROUND_UP) {
-            if (intpart >= 0) {
-                floatpart = ceil(floatpart);
-                if (floatpart >= denominator) {
-                    floatpart = 0.0;
-                    intpart += 1.0;
-                }
-            }
-            else {
-                floatpart = floor(floatpart);
+        if (round == _PyTime_ROUND_CEILING) {
+            floatpart = ceil(floatpart);
+            if (floatpart >= denominator) {
+                floatpart = 0.0;
+                intpart += 1.0;
             }
         }
+        else {
+            floatpart = floor(floatpart);
+        }
 
         *sec = (time_t)intpart;
         err = intpart - (double)*sec;
@@ -207,12 +115,10 @@ _PyTime_ObjectToTime_t(PyObject *obj, time_t *sec, _PyTime_round_t round)
         double d, intpart, err;
 
         d = PyFloat_AsDouble(obj);
-        if (round == _PyTime_ROUND_UP) {
-            if (d >= 0)
-                d = ceil(d);
-            else
-                d = floor(d);
-        }
+        if (round == _PyTime_ROUND_CEILING)
+            d = ceil(d);
+        else
+            d = floor(d);
         (void)modf(d, &intpart);
 
         *sec = (time_t)intpart;
@@ -245,8 +151,528 @@ _PyTime_ObjectToTimeval(PyObject *obj, time_t *sec, long *usec,
     return _PyTime_ObjectToDenominator(obj, sec, usec, 1e6, round);
 }
 
-void
-_PyTime_Init()
+static void
+_PyTime_overflow(void)
+{
+    PyErr_SetString(PyExc_OverflowError,
+                    "timestamp too large to convert to C _PyTime_t");
+}
+
+_PyTime_t
+_PyTime_FromSeconds(int seconds)
+{
+    _PyTime_t t;
+    /* ensure that integer overflow cannot happen, int type should have 32
+       bits, whereas _PyTime_t type has at least 64 bits (SEC_TO_MS takes 30
+       bits). */
+    assert((seconds >= 0 && seconds <= _PyTime_MAX / SEC_TO_NS)
+           || (seconds < 0 && seconds >= _PyTime_MIN / SEC_TO_NS));
+    t = (_PyTime_t)seconds * SEC_TO_NS;
+    return t;
+}
+
+_PyTime_t
+_PyTime_FromNanoseconds(PY_LONG_LONG ns)
+{
+    _PyTime_t t;
+    assert(sizeof(PY_LONG_LONG) <= sizeof(_PyTime_t));
+    t = Py_SAFE_DOWNCAST(ns, PY_LONG_LONG, _PyTime_t);
+    return t;
+}
+
+#ifdef HAVE_CLOCK_GETTIME
+static int
+_PyTime_FromTimespec(_PyTime_t *tp, struct timespec *ts, int raise)
+{
+    _PyTime_t t;
+    int res = 0;
+
+    t = (_PyTime_t)ts->tv_sec * SEC_TO_NS;
+    if (t / SEC_TO_NS != ts->tv_sec) {
+        if (raise)
+            _PyTime_overflow();
+        res = -1;
+    }
+
+    t += ts->tv_nsec;
+
+    *tp = t;
+    return res;
+}
+#elif !defined(MS_WINDOWS)
+static int
+_PyTime_FromTimeval(_PyTime_t *tp, struct timeval *tv, int raise)
+{
+    _PyTime_t t;
+    int res = 0;
+
+    t = (_PyTime_t)tv->tv_sec * SEC_TO_NS;
+    if (t / SEC_TO_NS != tv->tv_sec) {
+        if (raise)
+            _PyTime_overflow();
+        res = -1;
+    }
+
+    t += (_PyTime_t)tv->tv_usec * US_TO_NS;
+
+    *tp = t;
+    return res;
+}
+#endif
+
+static int
+_PyTime_FromObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round,
+                   long to_nanoseconds)
+{
+    if (PyFloat_Check(obj)) {
+        /* volatile avoids unsafe optimization on float enabled by gcc -O3 */
+        volatile double d, err;
+
+        /* convert to a number of nanoseconds */
+        d = PyFloat_AsDouble(obj);
+        d *= to_nanoseconds;
+
+        if (round == _PyTime_ROUND_CEILING)
+            d = ceil(d);
+        else
+            d = floor(d);
+
+        *t = (_PyTime_t)d;
+        err = d - (double)*t;
+        if (fabs(err) >= 1.0) {
+            _PyTime_overflow();
+            return -1;
+        }
+        return 0;
+    }
+    else {
+#ifdef HAVE_LONG_LONG
+        PY_LONG_LONG sec;
+        sec = PyLong_AsLongLong(obj);
+        assert(sizeof(PY_LONG_LONG) <= sizeof(_PyTime_t));
+#else
+        long sec;
+        sec = PyLong_AsLong(obj);
+        assert(sizeof(PY_LONG_LONG) <= sizeof(_PyTime_t));
+#endif
+        if (sec == -1 && PyErr_Occurred()) {
+            if (PyErr_ExceptionMatches(PyExc_OverflowError))
+                _PyTime_overflow();
+            return -1;
+        }
+        *t = sec * to_nanoseconds;
+        if (*t / to_nanoseconds != sec) {
+            _PyTime_overflow();
+            return -1;
+        }
+        return 0;
+    }
+}
+
+int
+_PyTime_FromSecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
+{
+    return _PyTime_FromObject(t, obj, round, SEC_TO_NS);
+}
+
+int
+_PyTime_FromMillisecondsObject(_PyTime_t *t, PyObject *obj, _PyTime_round_t round)
+{
+    return _PyTime_FromObject(t, obj, round, MS_TO_NS);
+}
+
+double
+_PyTime_AsSecondsDouble(_PyTime_t t)
+{
+    _PyTime_t sec, ns;
+    /* Divide using integers to avoid rounding issues on the integer part.
+       1e-9 cannot be stored exactly in IEEE 64-bit. */
+    sec = t / SEC_TO_NS;
+    ns = t % SEC_TO_NS;
+    return (double)sec + (double)ns * 1e-9;
+}
+
+PyObject *
+_PyTime_AsNanosecondsObject(_PyTime_t t)
+{
+#ifdef HAVE_LONG_LONG
+    assert(sizeof(PY_LONG_LONG) >= sizeof(_PyTime_t));
+    return PyLong_FromLongLong((PY_LONG_LONG)t);
+#else
+    assert(sizeof(long) >= sizeof(_PyTime_t));
+    return PyLong_FromLong((long)t);
+#endif
+}
+
+static _PyTime_t
+_PyTime_Divide(_PyTime_t t, _PyTime_t k, _PyTime_round_t round)
+{
+    assert(k > 1);
+    if (round == _PyTime_ROUND_CEILING) {
+        if (t >= 0)
+            return (t + k - 1) / k;
+        else
+            return (t - (k - 1)) / k;
+    }
+    else
+        return t / k;
+}
+
+_PyTime_t
+_PyTime_AsMilliseconds(_PyTime_t t, _PyTime_round_t round)
+{
+    return _PyTime_Divide(t, NS_TO_MS, round);
+}
+
+_PyTime_t
+_PyTime_AsMicroseconds(_PyTime_t t, _PyTime_round_t round)
+{
+    return _PyTime_Divide(t, NS_TO_US, round);
+}
+
+static int
+_PyTime_AsTimeval_impl(_PyTime_t t, struct timeval *tv, _PyTime_round_t round,
+                       int raise)
+{
+    _PyTime_t secs, ns;
+    int res = 0;
+
+    secs = t / SEC_TO_NS;
+    ns = t % SEC_TO_NS;
+    if (ns < 0) {
+        ns += SEC_TO_NS;
+        secs -= 1;
+    }
+
+#ifdef MS_WINDOWS
+    /* On Windows, timeval.tv_sec is a long (32 bit),
+       whereas time_t can be 64-bit. */
+    assert(sizeof(tv->tv_sec) == sizeof(long));
+#if SIZEOF_TIME_T > SIZEOF_LONG
+    if (secs > LONG_MAX) {
+        secs = LONG_MAX;
+        res = -1;
+    }
+    else if (secs < LONG_MIN) {
+        secs = LONG_MIN;
+        res = -1;
+    }
+#endif
+    tv->tv_sec = (long)secs;
+#else
+    /* On OpenBSD 5.4, timeval.tv_sec is a long.
+       Example: long is 64-bit, whereas time_t is 32-bit. */
+    tv->tv_sec = secs;
+    if ((_PyTime_t)tv->tv_sec != secs)
+        res = -1;
+#endif
+
+    if (round == _PyTime_ROUND_CEILING)
+        tv->tv_usec = (int)((ns + US_TO_NS - 1) / US_TO_NS);
+    else
+        tv->tv_usec = (int)(ns / US_TO_NS);
+
+    if (tv->tv_usec >= SEC_TO_US) {
+        tv->tv_usec -= SEC_TO_US;
+        tv->tv_sec += 1;
+    }
+
+    if (res && raise)
+        _PyTime_overflow();
+
+    assert(0 <= tv->tv_usec && tv->tv_usec <= 999999);
+    return res;
+}
+
+int
+_PyTime_AsTimeval(_PyTime_t t, struct timeval *tv, _PyTime_round_t round)
 {
-    /* Do nothing.  Needed to force linking. */
+    return _PyTime_AsTimeval_impl(t, tv, round, 1);
+}
+
+int
+_PyTime_AsTimeval_noraise(_PyTime_t t, struct timeval *tv, _PyTime_round_t round)
+{
+    return _PyTime_AsTimeval_impl(t, tv, round, 0);
+}
+
+#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_KQUEUE)
+int
+_PyTime_AsTimespec(_PyTime_t t, struct timespec *ts)
+{
+    _PyTime_t secs, nsec;
+
+    secs = t / SEC_TO_NS;
+    nsec = t % SEC_TO_NS;
+    if (nsec < 0) {
+        nsec += SEC_TO_NS;
+        secs -= 1;
+    }
+    ts->tv_sec = (time_t)secs;
+    if ((_PyTime_t)ts->tv_sec != secs) {
+        _PyTime_overflow();
+        return -1;
+    }
+    ts->tv_nsec = nsec;
+
+    assert(0 <= ts->tv_nsec && ts->tv_nsec <= 999999999);
+    return 0;
+}
+#endif
+
+static int
+pygettimeofday_new(_PyTime_t *tp, _Py_clock_info_t *info, int raise)
+{
+#ifdef MS_WINDOWS
+    FILETIME system_time;
+    ULARGE_INTEGER large;
+
+    assert(info == NULL || raise);
+
+    GetSystemTimeAsFileTime(&system_time);
+    large.u.LowPart = system_time.dwLowDateTime;
+    large.u.HighPart = system_time.dwHighDateTime;
+    /* 11,644,473,600,000,000,000: number of nanoseconds between
+       the 1st january 1601 and the 1st january 1970 (369 years + 89 leap
+       days). */
+    *tp = large.QuadPart * 100 - 11644473600000000000;
+    if (info) {
+        DWORD timeAdjustment, timeIncrement;
+        BOOL isTimeAdjustmentDisabled, ok;
+
+        info->implementation = "GetSystemTimeAsFileTime()";
+        info->monotonic = 0;
+        ok = GetSystemTimeAdjustment(&timeAdjustment, &timeIncrement,
+                                     &isTimeAdjustmentDisabled);
+        if (!ok) {
+            PyErr_SetFromWindowsErr(0);
+            return -1;
+        }
+        info->resolution = timeIncrement * 1e-7;
+        info->adjustable = 1;
+    }
+
+#else   /* MS_WINDOWS */
+    int err;
+#ifdef HAVE_CLOCK_GETTIME
+    struct timespec ts;
+#else
+    struct timeval tv;
+#endif
+
+    assert(info == NULL || raise);
+
+#ifdef HAVE_CLOCK_GETTIME
+    err = clock_gettime(CLOCK_REALTIME, &ts);
+    if (err) {
+        if (raise)
+            PyErr_SetFromErrno(PyExc_OSError);
+        return -1;
+    }
+    if (_PyTime_FromTimespec(tp, &ts, raise) < 0)
+        return -1;
+
+    if (info) {
+        struct timespec res;
+        info->implementation = "clock_gettime(CLOCK_REALTIME)";
+        info->monotonic = 0;
+        info->adjustable = 1;
+        if (clock_getres(CLOCK_REALTIME, &res) == 0)
+            info->resolution = res.tv_sec + res.tv_nsec * 1e-9;
+        else
+            info->resolution = 1e-9;
+    }
+#else   /* HAVE_CLOCK_GETTIME */
+
+     /* test gettimeofday() */
+#ifdef GETTIMEOFDAY_NO_TZ
+    err = gettimeofday(&tv);
+#else
+    err = gettimeofday(&tv, (struct timezone *)NULL);
+#endif
+    if (err) {
+        if (raise)
+            PyErr_SetFromErrno(PyExc_OSError);
+        return -1;
+    }
+    if (_PyTime_FromTimeval(tp, &tv, raise) < 0)
+        return -1;
+
+    if (info) {
+        info->implementation = "gettimeofday()";
+        info->resolution = 1e-6;
+        info->monotonic = 0;
+        info->adjustable = 1;
+    }
+#endif   /* !HAVE_CLOCK_GETTIME */
+#endif   /* !MS_WINDOWS */
+    return 0;
+}
+
+_PyTime_t
+_PyTime_GetSystemClock(void)
+{
+    _PyTime_t t;
+    if (pygettimeofday_new(&t, NULL, 0) < 0) {
+        /* should not happen, _PyTime_Init() checked the clock at startup */
+        assert(0);
+
+        /* use a fixed value instead of a random value from the stack */
+        t = 0;
+    }
+    return t;
+}
+
+int
+_PyTime_GetSystemClockWithInfo(_PyTime_t *t, _Py_clock_info_t *info)
+{
+    return pygettimeofday_new(t, info, 1);
+}
+
+
+static int
+pymonotonic_new(_PyTime_t *tp, _Py_clock_info_t *info, int raise)
+{
+#ifdef Py_DEBUG
+    static int last_set = 0;
+    static _PyTime_t last = 0;
+#endif
+#if defined(MS_WINDOWS)
+    ULONGLONG result;
+
+    assert(info == NULL || raise);
+
+    result = GetTickCount64();
+
+    *tp = result * MS_TO_NS;
+    if (*tp / MS_TO_NS != result) {
+        if (raise) {
+            _PyTime_overflow();
+            return -1;
+        }
+        /* Hello, time traveler! */
+        assert(0);
+    }
+
+    if (info) {
+        DWORD timeAdjustment, timeIncrement;
+        BOOL isTimeAdjustmentDisabled, ok;
+        info->implementation = "GetTickCount64()";
+        info->monotonic = 1;
+        ok = GetSystemTimeAdjustment(&timeAdjustment, &timeIncrement,
+                                     &isTimeAdjustmentDisabled);
+        if (!ok) {
+            PyErr_SetFromWindowsErr(0);
+            return -1;
+        }
+        info->resolution = timeIncrement * 1e-7;
+        info->adjustable = 0;
+    }
+
+#elif defined(__APPLE__)
+    static mach_timebase_info_data_t timebase;
+    uint64_t time;
+
+    if (timebase.denom == 0) {
+        /* According to the Technical Q&A QA1398, mach_timebase_info() cannot
+           fail: https://developer.apple.com/library/mac/#qa/qa1398/ */
+        (void)mach_timebase_info(&timebase);
+    }
+
+    time = mach_absolute_time();
+
+    /* apply timebase factor */
+    time *= timebase.numer;
+    time /= timebase.denom;
+
+    *tp = time;
+
+    if (info) {
+        info->implementation = "mach_absolute_time()";
+        info->resolution = (double)timebase.numer / timebase.denom * 1e-9;
+        info->monotonic = 1;
+        info->adjustable = 0;
+    }
+
+#else
+    struct timespec ts;
+#ifdef CLOCK_HIGHRES
+    const clockid_t clk_id = CLOCK_HIGHRES;
+    const char *implementation = "clock_gettime(CLOCK_HIGHRES)";
+#else
+    const clockid_t clk_id = CLOCK_MONOTONIC;
+    const char *implementation = "clock_gettime(CLOCK_MONOTONIC)";
+#endif
+
+    assert(info == NULL || raise);
+
+    if (clock_gettime(clk_id, &ts) != 0) {
+        if (raise) {
+            PyErr_SetFromErrno(PyExc_OSError);
+            return -1;
+        }
+        return -1;
+    }
+
+    if (info) {
+        struct timespec res;
+        info->monotonic = 1;
+        info->implementation = implementation;
+        info->adjustable = 0;
+        if (clock_getres(clk_id, &res) != 0) {
+            PyErr_SetFromErrno(PyExc_OSError);
+            return -1;
+        }
+        info->resolution = res.tv_sec + res.tv_nsec * 1e-9;
+    }
+    if (_PyTime_FromTimespec(tp, &ts, raise) < 0)
+        return -1;
+#endif
+#ifdef Py_DEBUG
+    /* monotonic clock cannot go backward */
+    assert(!last_set || last <= *tp);
+    last = *tp;
+    last_set = 1;
+#endif
+    return 0;
+}
+
+_PyTime_t
+_PyTime_GetMonotonicClock(void)
+{
+    _PyTime_t t;
+    if (pymonotonic_new(&t, NULL, 0) < 0) {
+        /* should not happen, _PyTime_Init() checked that monotonic clock at
+           startup */
+        assert(0);
+
+        /* use a fixed value instead of a random value from the stack */
+        t = 0;
+    }
+    return t;
+}
+
+int
+_PyTime_GetMonotonicClockWithInfo(_PyTime_t *tp, _Py_clock_info_t *info)
+{
+    return pymonotonic_new(tp, info, 1);
+}
+
+int
+_PyTime_Init(void)
+{
+    _PyTime_t t;
+
+    /* ensure that the system clock works */
+    if (_PyTime_GetSystemClockWithInfo(&t, NULL) < 0)
+        return -1;
+
+    /* ensure that the operating system provides a monotonic clock */
+    if (_PyTime_GetMonotonicClockWithInfo(&t, NULL) < 0)
+        return -1;
+
+    /* check that _PyTime_FromSeconds() cannot overflow */
+    assert(INT_MAX <= _PyTime_MAX / SEC_TO_NS);
+    assert(INT_MIN >= _PyTime_MIN / SEC_TO_NS);
+    return 0;
 }