cosmopolitan/third_party/python/Modules/timemodule.c

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=4 sts=4 sw=4 fenc=utf-8                                :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Python 3                                                                     │
│ https://docs.python.org/3/license.html                                       │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/struct/rusage.h"
#include "libc/calls/struct/timespec.h"
#include "libc/calls/struct/tms.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/fmt/conv.h"
#include "libc/nt/accounting.h"
#include "libc/nt/runtime.h"
#include "libc/runtime/clktck.h"
#include "libc/sock/select.h"
#include "libc/sysv/consts/clock.h"
#include "libc/sysv/consts/rusage.h"
#include "libc/time/struct/tm.h"
#include "libc/time/time.h"
#include "third_party/python/Include/abstract.h"
#include "third_party/python/Include/boolobject.h"
#include "third_party/python/Include/ceval.h"
#include "third_party/python/Include/dictobject.h"
#include "third_party/python/Include/floatobject.h"
#include "third_party/python/Include/import.h"
#include "third_party/python/Include/longobject.h"
#include "third_party/python/Include/modsupport.h"
#include "third_party/python/Include/namespaceobject.h"
#include "third_party/python/Include/object.h"
#include "third_party/python/Include/pyerrors.h"
#include "third_party/python/Include/pymacro.h"
#include "third_party/python/Include/pymem.h"
#include "third_party/python/Include/pytime.h"
#include "third_party/python/Include/structseq.h"
#include "third_party/python/Include/yoink.h"
#include "third_party/python/pyconfig.h"
/* clang-format off */

PYTHON_PROVIDE("time");
PYTHON_PROVIDE("time.CLOCK_MONOTONIC");
PYTHON_PROVIDE("time.CLOCK_MONOTONIC_RAW");
PYTHON_PROVIDE("time.CLOCK_PROCESS_CPUTIME_ID");
PYTHON_PROVIDE("time.CLOCK_REALTIME");
PYTHON_PROVIDE("time.CLOCK_THREAD_CPUTIME_ID");
PYTHON_PROVIDE("time._STRUCT_TM_ITEMS");
PYTHON_PROVIDE("time.altzone");
PYTHON_PROVIDE("time.asctime");
PYTHON_PROVIDE("time.clock");
PYTHON_PROVIDE("time.clock_getres");
PYTHON_PROVIDE("time.clock_gettime");
PYTHON_PROVIDE("time.ctime");
PYTHON_PROVIDE("time.daylight");
PYTHON_PROVIDE("time.get_clock_info");
PYTHON_PROVIDE("time.gmtime");
PYTHON_PROVIDE("time.localtime");
PYTHON_PROVIDE("time.mktime");
PYTHON_PROVIDE("time.monotonic");
PYTHON_PROVIDE("time.perf_counter");
PYTHON_PROVIDE("time.process_time");
PYTHON_PROVIDE("time.sleep");
PYTHON_PROVIDE("time.strftime");
PYTHON_PROVIDE("time.strptime");
PYTHON_PROVIDE("time.struct_time");
PYTHON_PROVIDE("time.time");
PYTHON_PROVIDE("time.timezone");
PYTHON_PROVIDE("time.tzname");
PYTHON_PROVIDE("time.tzset");

PYTHON_YOINK("_strptime");

typedef int clockid_t;
#undef HAVE_CLOCK_SETTIME

/* Forward declarations */
static int pysleep(_PyTime_t);
static PyObject *floattime(_Py_clock_info_t *info);

static PyObject *
_PyFloat_FromPyTime(_PyTime_t t)
{
    double d = _PyTime_AsSecondsDouble(t);
    return PyFloat_FromDouble(d);
}

static PyObject *
time_time(PyObject *self, PyObject *unused)
{
    return floattime(NULL);
}

PyDoc_STRVAR(time_doc,
"time() -> floating point number\n\
\n\
Return the current time in seconds since the Epoch.\n\
Fractions of a second may be present if the system clock provides them.");

static PyObject *
time_time_ns(PyObject *self, PyObject *unused)
{
    _PyTime_t t;
    if (_PyTime_GetSystemClockWithInfo(&t, 0)) return 0;
    return _PyTime_AsNanosecondsObject(t);
}

PyDoc_STRVAR(time_ns_doc,
"time_ns($module)\n\
\n\
Return the current time in nanoseconds since the Epoch.");

#ifdef HAVE_CLOCK
static PyObject *
floatclock(_Py_clock_info_t *info)
{
    clock_t value;
    value = clock();
    if (value == (clock_t)-1) {
        PyErr_SetString(PyExc_RuntimeError,
                "the processor time used is not available "
                "or its value cannot be represented");
        return NULL;
    }
    if (info) {
        info->implementation = "clock()";
        info->resolution = 1 / (double)CLOCKS_PER_SEC;
        info->monotonic = 1;
        info->adjustable = 0;
    }
    return PyFloat_FromDouble((double)value / CLOCKS_PER_SEC);
}
#endif /* HAVE_CLOCK */

#ifdef MS_WINDOWS
#define WIN32_PERF_COUNTER
/* Win32 has better clock replacement; we have our own version, due to Mark
   Hammond and Tim Peters */
static PyObject*
win_perf_counter(_Py_clock_info_t *info)
{
    static LONGLONG cpu_frequency = 0;
    static LONGLONG ctrStart;
    LARGE_INTEGER now;
    double diff;
    if (cpu_frequency == 0) {
        LARGE_INTEGER freq;
        QueryPerformanceCounter(&now);
        ctrStart = now.QuadPart;
        if (!QueryPerformanceFrequency(&freq) || freq.QuadPart == 0) {
            PyErr_SetFromWindowsErr(0);
            return NULL;
        }
        cpu_frequency = freq.QuadPart;
    }
    QueryPerformanceCounter(&now);
    diff = (double)(now.QuadPart - ctrStart);
    if (info) {
        info->implementation = "QueryPerformanceCounter()";
        info->resolution = 1.0 / (double)cpu_frequency;
        info->monotonic = 1;
        info->adjustable = 0;
    }
    return PyFloat_FromDouble(diff / (double)cpu_frequency);
}
#endif   /* MS_WINDOWS */

#if defined(WIN32_PERF_COUNTER) || defined(HAVE_CLOCK)
#define PYCLOCK
static PyObject*
pyclock(_Py_clock_info_t *info)
{
#ifdef WIN32_PERF_COUNTER
    return win_perf_counter(info);
#else
    return floatclock(info);
#endif
}

static PyObject *
time_clock(PyObject *self, PyObject *unused)
{
    return pyclock(NULL);
}

PyDoc_STRVAR(clock_doc,
"clock() -> floating point number\n\
\n\
Return the CPU time or real time since the start of the process or since\n\
the first call to clock().  This has as much precision as the system\n\
records.");
#endif

#ifdef HAVE_CLOCK_GETTIME

static PyObject *
time_clock_gettime(PyObject *self, PyObject *args)
{
    int ret;
    int clk_id;
    struct timespec tp;
    if (!PyArg_ParseTuple(args, "i:clock_gettime", &clk_id))
        return NULL;
    ret = clock_gettime((clockid_t)clk_id, &tp);
    if (ret != 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    return PyFloat_FromDouble(tp.tv_sec + tp.tv_nsec * 1e-9);
}

PyDoc_STRVAR(clock_gettime_doc,
"clock_gettime(clk_id) -> floating point number\n\
\n\
Return the time of the specified clock clk_id.");

static PyObject *
time_clock_gettime_ns(PyObject *self, PyObject *args)
{
    int clk_id;
    _PyTime_t t;
    struct timespec ts;
    if (!PyArg_ParseTuple(args, "i:clock_gettime", &clk_id)) return 0;
    if (clock_gettime((clockid_t)clk_id, &ts)) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    if (_PyTime_FromTimespec(&t, &ts) < 0) return 0;
    return _PyTime_AsNanosecondsObject(t);
}

PyDoc_STRVAR(clock_gettime_ns_doc,
"clock_gettime_ns($module, clk_id)\n\
--\n\n\
Return the time of the specified clock clk_id as nanoseconds.");

#endif   /* HAVE_CLOCK_GETTIME */

#if HAVE_CLOCK_SETTIME
static PyObject *
time_clock_settime(PyObject *self, PyObject *args)
{
    int clk_id;
    PyObject *obj;
    _PyTime_t t;
    struct timespec tp;
    int ret;
    if (!PyArg_ParseTuple(args, "iO:clock_settime", &clk_id, &obj))
        return NULL;
    if (_PyTime_FromSecondsObject(&t, obj, _PyTime_ROUND_FLOOR) < 0)
        return NULL;
    if (_PyTime_AsTimespec(t, &tp) == -1)
        return NULL;
    ret = clock_settime((clockid_t)clk_id, &tp);
    if (ret != 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    Py_RETURN_NONE;
}

PyDoc_STRVAR(clock_settime_doc,
"clock_settime(clk_id, time)\n\
\n\
Set the time of the specified clock clk_id.");
#endif   /* HAVE_CLOCK_SETTIME */

#ifdef HAVE_CLOCK_GETRES
static PyObject *
time_clock_getres(PyObject *self, PyObject *args)
{
    int ret;
    int clk_id;
    struct timespec tp;
    if (!PyArg_ParseTuple(args, "i:clock_getres", &clk_id))
        return NULL;
    ret = clock_getres((clockid_t)clk_id, &tp);
    if (ret != 0) {
        PyErr_SetFromErrno(PyExc_OSError);
        return NULL;
    }
    return PyFloat_FromDouble(tp.tv_sec + tp.tv_nsec * 1e-9);
}

PyDoc_STRVAR(clock_getres_doc,
"clock_getres(clk_id) -> floating point number\n\
\n\
Return the resolution (precision) of the specified clock clk_id.");
#endif   /* HAVE_CLOCK_GETRES */

static PyObject *
time_sleep(PyObject *self, PyObject *obj)
{
    _PyTime_t secs;
    if (_PyTime_FromSecondsObject(&secs, obj, _PyTime_ROUND_TIMEOUT))
        return NULL;
    if (secs < 0) {
        PyErr_SetString(PyExc_ValueError,
                        "sleep length must be non-negative");
        return NULL;
    }
    if (pysleep(secs) != 0)
        return NULL;
    Py_INCREF(Py_None);
    return Py_None;
}

PyDoc_STRVAR(sleep_doc,
"sleep(seconds)\n\
\n\
Delay execution for a given number of seconds.  The argument may be\n\
a floating point number for subsecond precision.");

static PyStructSequence_Field struct_time_type_fields[] = {
    {"tm_year", PyDoc_STR("year, for example, 1993")},
    {"tm_mon", PyDoc_STR("month of year, range [1, 12]")},
    {"tm_mday", PyDoc_STR("day of month, range [1, 31]")},
    {"tm_hour", PyDoc_STR("hours, range [0, 23]")},
    {"tm_min", PyDoc_STR("minutes, range [0, 59]")},
    {"tm_sec", PyDoc_STR("seconds, range [0, 61])")},
    {"tm_wday", PyDoc_STR("day of week, range [0, 6], Monday is 0")},
    {"tm_yday", PyDoc_STR("day of year, range [1, 366]")},
    {"tm_isdst", PyDoc_STR("1 if summer time is in effect, 0 if not, and -1 if unknown")},
    {"tm_zone", PyDoc_STR("abbreviation of timezone name")},
    {"tm_gmtoff", PyDoc_STR("offset from UTC in seconds")},
    {0}
};

static PyStructSequence_Desc struct_time_type_desc = {
    "time.struct_time",
    "The time value as returned by gmtime(), localtime(), and strptime(), and\n"
    " accepted by asctime(), mktime() and strftime().  May be considered as a\n"
    " sequence of 9 integers.\n\n"
    " Note that several fields' values are not the same as those defined by\n"
    " the C language standard for struct tm.  For example, the value of the\n"
    " field tm_year is the actual year, not year - 1900.  See individual\n"
    " fields' descriptions for details.",
    struct_time_type_fields,
    9,
};

static int initialized;
static PyTypeObject StructTimeType;


static PyObject *
tmtotuple(struct tm *p
#ifndef HAVE_STRUCT_TM_TM_ZONE
        , const char *zone, time_t gmtoff
#endif
)
{
    PyObject *v = PyStructSequence_New(&StructTimeType);
    if (v == NULL)
        return NULL;

#define SET(i,val) PyStructSequence_SET_ITEM(v, i, PyLong_FromLong((long) val))

    SET(0, p->tm_year + 1900);
    SET(1, p->tm_mon + 1);         /* Want January == 1 */
    SET(2, p->tm_mday);
    SET(3, p->tm_hour);
    SET(4, p->tm_min);
    SET(5, p->tm_sec);
    SET(6, (p->tm_wday + 6) % 7); /* Want Monday == 0 */
    SET(7, p->tm_yday + 1);        /* Want January, 1 == 1 */
    SET(8, p->tm_isdst);
#ifdef HAVE_STRUCT_TM_TM_ZONE
    PyStructSequence_SET_ITEM(v, 9,
        PyUnicode_DecodeLocale(p->tm_zone, "surrogateescape"));
    SET(10, p->tm_gmtoff);
#else
    PyStructSequence_SET_ITEM(v, 9,
        PyUnicode_DecodeLocale(zone, "surrogateescape"));
    PyStructSequence_SET_ITEM(v, 10, _PyLong_FromTime_t(gmtoff));
#endif /* HAVE_STRUCT_TM_TM_ZONE */
#undef SET
    if (PyErr_Occurred()) {
        Py_XDECREF(v);
        return NULL;
    }

    return v;
}

static int64_t
Time(int64_t *tp) {
    struct timespec ts;
    clock_gettime(CLOCK_REALTIME, &ts);
    if (tp) *tp = ts.tv_sec;
    return ts.tv_sec;
}

/* Parse arg tuple that can contain an optional float-or-None value;
   format needs to be "|O:name".
   Returns non-zero on success (parallels PyArg_ParseTuple).
*/
static int
parse_time_t_args(PyObject *args, const char *format, time_t *pwhen)
{
    PyObject *ot = NULL;
    time_t whent;
    if (!PyArg_ParseTuple(args, format, &ot))
        return 0;
    if (ot == NULL || ot == Py_None) {
        whent = Time(NULL);
    }
    else {
        if (_PyTime_ObjectToTime_t(ot, &whent, _PyTime_ROUND_FLOOR) == -1)
            return 0;
    }
    *pwhen = whent;
    return 1;
}

static PyObject *
time_gmtime(PyObject *self, PyObject *args)
{
    time_t when;
    struct tm buf;
    if (!parse_time_t_args(args, "|O:gmtime", &when))
        return NULL;
    errno = 0;
    if (_PyTime_gmtime(when, &buf) != 0)
        return NULL;
#ifdef HAVE_STRUCT_TM_TM_ZONE
    return tmtotuple(&buf);
#else
    return tmtotuple(&buf, "UTC", 0);
#endif
}

#ifndef HAVE_TIMEGM
static time_t
timegm(struct tm *p)
{
    /* XXX: the following implementation will not work for tm_year < 1970.
       but it is likely that platforms that don't have timegm do not support
       negative timestamps anyways. */
    return p->tm_sec + p->tm_min*60 + p->tm_hour*3600 + p->tm_yday*86400 +
        (p->tm_year-70)*31536000 + ((p->tm_year-69)/4)*86400 -
        ((p->tm_year-1)/100)*86400 + ((p->tm_year+299)/400)*86400;
}
#endif

PyDoc_STRVAR(gmtime_doc,
"gmtime([seconds]) -> (tm_year, tm_mon, tm_mday, tm_hour, tm_min,\n\
                       tm_sec, tm_wday, tm_yday, tm_isdst)\n\
\n\
Convert seconds since the Epoch to a time tuple expressing UTC (a.k.a.\n\
GMT).  When 'seconds' is not passed in, convert the current time instead.\n\
\n\
If the platform supports the tm_gmtoff and tm_zone, they are available as\n\
attributes only.");

static PyObject *
time_localtime(PyObject *self, PyObject *args)
{
    time_t when;
    struct tm buf;
    if (!parse_time_t_args(args, "|O:localtime", &when))
        return NULL;
    if (_PyTime_localtime(when, &buf) != 0)
        return NULL;
#ifdef HAVE_STRUCT_TM_TM_ZONE
    return tmtotuple(&buf);
#else
    {
        struct tm local = buf;
        char zone[100];
        time_t gmtoff;
        strftime(zone, sizeof(zone), "%Z", &buf);
        gmtoff = timegm(&buf) - when;
        return tmtotuple(&local, zone, gmtoff);
    }
#endif
}

PyDoc_STRVAR(localtime_doc,
"localtime([seconds]) -> (tm_year,tm_mon,tm_mday,tm_hour,tm_min,\n\
                          tm_sec,tm_wday,tm_yday,tm_isdst)\n\
\n\
Convert seconds since the Epoch to a time tuple expressing local time.\n\
When 'seconds' is not passed in, convert the current time instead.");

/* Convert 9-item tuple to tm structure.  Return 1 on success, set
 * an exception and return 0 on error.
 */
static int
gettmarg(PyObject *args, struct tm *p)
{
    int y;

    bzero(p, sizeof(struct tm));

    if (!PyTuple_Check(args)) {
        PyErr_SetString(PyExc_TypeError,
                        "Tuple or struct_time argument required");
        return 0;
    }

    if (!PyArg_ParseTuple(args, "iiiiiiiii",
                          &y, &p->tm_mon, &p->tm_mday,
                          &p->tm_hour, &p->tm_min, &p->tm_sec,
                          &p->tm_wday, &p->tm_yday, &p->tm_isdst))
        return 0;

    if (y < INT_MIN + 1900) {
        PyErr_SetString(PyExc_OverflowError, "year out of range");
        return 0;
    }

    p->tm_year = y - 1900;
    p->tm_mon--;
    p->tm_wday = (p->tm_wday + 1) % 7;
    p->tm_yday--;
#ifdef HAVE_STRUCT_TM_TM_ZONE
    if (Py_TYPE(args) == &StructTimeType) {
        PyObject *item;
        item = PyTuple_GET_ITEM(args, 9);
        p->tm_zone = item == Py_None ? NULL : PyUnicode_AsUTF8(item);
        item = PyTuple_GET_ITEM(args, 10);
        p->tm_gmtoff = item == Py_None ? 0 : PyLong_AsLong(item);
        if (PyErr_Occurred())
            return 0;
    }
#endif /* HAVE_STRUCT_TM_TM_ZONE */
    return 1;
}

/* Check values of the struct tm fields before it is passed to strftime() and
 * asctime().  Return 1 if all values are valid, otherwise set an exception
 * and returns 0.
 */
static int
checktm(struct tm* buf)
{
    /* Checks added to make sure strftime() and asctime() does not crash Python by
       indexing blindly into some array for a textual representation
       by some bad index (fixes bug #897625 and #6608).

       Also support values of zero from Python code for arguments in which
       that is out of range by forcing that value to the lowest value that
       is valid (fixed bug #1520914).

       Valid ranges based on what is allowed in struct tm:

       - tm_year: [0, max(int)] (1)
       - tm_mon: [0, 11] (2)
       - tm_mday: [1, 31]
       - tm_hour: [0, 23]
       - tm_min: [0, 59]
       - tm_sec: [0, 60]
       - tm_wday: [0, 6] (1)
       - tm_yday: [0, 365] (2)
       - tm_isdst: [-max(int), max(int)]

       (1) gettmarg() handles bounds-checking.
       (2) Python's acceptable range is one greater than the range in C,
       thus need to check against automatic decrement by gettmarg().
    */
    if (buf->tm_mon == -1)
        buf->tm_mon = 0;
    else if (buf->tm_mon < 0 || buf->tm_mon > 11) {
        PyErr_SetString(PyExc_ValueError, "month out of range");
        return 0;
    }
    if (buf->tm_mday == 0)
        buf->tm_mday = 1;
    else if (buf->tm_mday < 0 || buf->tm_mday > 31) {
        PyErr_SetString(PyExc_ValueError, "day of month out of range");
        return 0;
    }
    if (buf->tm_hour < 0 || buf->tm_hour > 23) {
        PyErr_SetString(PyExc_ValueError, "hour out of range");
        return 0;
    }
    if (buf->tm_min < 0 || buf->tm_min > 59) {
        PyErr_SetString(PyExc_ValueError, "minute out of range");
        return 0;
    }
    if (buf->tm_sec < 0 || buf->tm_sec > 61) {
        PyErr_SetString(PyExc_ValueError, "seconds out of range");
        return 0;
    }
    /* tm_wday does not need checking of its upper-bound since taking
    ``% 7`` in gettmarg() automatically restricts the range. */
    if (buf->tm_wday < 0) {
        PyErr_SetString(PyExc_ValueError, "day of week out of range");
        return 0;
    }
    if (buf->tm_yday == -1)
        buf->tm_yday = 0;
    else if (buf->tm_yday < 0 || buf->tm_yday > 365) {
        PyErr_SetString(PyExc_ValueError, "day of year out of range");
        return 0;
    }
    return 1;
}

#ifdef MS_WINDOWS
   /* wcsftime() doesn't format correctly time zones, see issue #10653 */
#  undef HAVE_WCSFTIME
#endif
#define STRFTIME_FORMAT_CODES \
"Commonly used format codes:\n\
\n\
%Y  Year with century as a decimal number.\n\
%m  Month as a decimal number [01,12].\n\
%d  Day of the month as a decimal number [01,31].\n\
%H  Hour (24-hour clock) as a decimal number [00,23].\n\
%M  Minute as a decimal number [00,59].\n\
%S  Second as a decimal number [00,61].\n\
%z  Time zone offset from UTC.\n\
%a  Locale's abbreviated weekday name.\n\
%A  Locale's full weekday name.\n\
%b  Locale's abbreviated month name.\n\
%B  Locale's full month name.\n\
%c  Locale's appropriate date and time representation.\n\
%I  Hour (12-hour clock) as a decimal number [01,12].\n\
%p  Locale's equivalent of either AM or PM.\n\
\n\
Other codes may be available on your platform.  See documentation for\n\
the C library strftime function.\n"

#ifdef HAVE_STRFTIME
#ifdef HAVE_WCSFTIME
#define time_char wchar_t
#define format_time wcsftime
#define time_strlen wcslen
#else
#define time_char char
#define format_time strftime
#define time_strlen strlen
#endif

static PyObject *
time_strftime(PyObject *self, PyObject *args)
{
    PyObject *tup = NULL;
    struct tm buf;
    const time_char *fmt;
#ifdef HAVE_WCSFTIME
    wchar_t *format;
#else
    PyObject *format;
#endif
    PyObject *format_arg;
    size_t fmtlen, buflen;
    time_char *outbuf = NULL;
    size_t i;
    PyObject *ret = NULL;

    bzero(&buf, sizeof(buf));

    /* Will always expect a unicode string to be passed as format.
       Given that there's no str type anymore in py3k this seems safe.
    */
    if (!PyArg_ParseTuple(args, "U|O:strftime", &format_arg, &tup))
        return NULL;

    if (tup == NULL) {
        time_t tt = Time(NULL);
        if (_PyTime_localtime(tt, &buf) != 0)
            return NULL;
    }
    else if (!gettmarg(tup, &buf) || !checktm(&buf))
        return NULL;

#if defined(_MSC_VER) || defined(sun) || defined(_AIX)
    if (buf.tm_year + 1900 < 1 || 9999 < buf.tm_year + 1900) {
        PyErr_SetString(PyExc_ValueError,
                        "strftime() requires year in [1; 9999]");
        return NULL;
    }
#endif

    /* Normalize tm_isdst just in case someone foolishly implements %Z
       based on the assumption that tm_isdst falls within the range of
       [-1, 1] */
    if (buf.tm_isdst < -1)
        buf.tm_isdst = -1;
    else if (buf.tm_isdst > 1)
        buf.tm_isdst = 1;

#ifdef HAVE_WCSFTIME
    format = _PyUnicode_AsWideCharString(format_arg);
    if (format == NULL)
        return NULL;
    fmt = format;
#else
    /* Convert the unicode string to an ascii one */
    format = PyUnicode_EncodeLocale(format_arg, "surrogateescape");
    if (format == NULL)
        return NULL;
    fmt = PyBytes_AS_STRING(format);
#endif

#if defined(MS_WINDOWS) && !defined(HAVE_WCSFTIME)
    /* check that the format string contains only valid directives */
    for (outbuf = strchr(fmt, '%');
        outbuf != NULL;
        outbuf = strchr(outbuf+2, '%'))
    {
        if (outbuf[1] == '#')
            ++outbuf; /* not documented by python, */
        if (outbuf[1] == '\0')
            break;
        if ((outbuf[1] == 'y') && buf.tm_year < 0) {
            PyErr_SetString(PyExc_ValueError,
                        "format %y requires year >= 1900 on Windows");
            Py_DECREF(format);
            return NULL;
        }
    }
#elif (defined(_AIX) || defined(sun)) && defined(HAVE_WCSFTIME)
    for (outbuf = wcschr(fmt, '%');
        outbuf != NULL;
        outbuf = wcschr(outbuf+2, '%'))
    {
        if (outbuf[1] == L'\0')
            break;
        /* Issue #19634: On AIX, wcsftime("y", (1899, 1, 1, 0, 0, 0, 0, 0, 0))
           returns "0/" instead of "99" */
        if (outbuf[1] == L'y' && buf.tm_year < 0) {
            PyErr_SetString(PyExc_ValueError,
                            "format %y requires year >= 1900 on AIX");
            PyMem_Free(format);
            return NULL;
        }
    }
#endif

    fmtlen = time_strlen(fmt);

    /* I hate these functions that presume you know how big the output
     * will be ahead of time...
     */
    for (i = 1024; ; i += i) {
        outbuf = (time_char *)PyMem_Malloc(i*sizeof(time_char));
        if (outbuf == NULL) {
            PyErr_NoMemory();
            break;
        }
#if defined _MSC_VER && _MSC_VER >= 1400 && defined(__STDC_SECURE_LIB__)
        errno = 0;
#endif
        _Py_BEGIN_SUPPRESS_IPH
        buflen = format_time(outbuf, i, fmt, &buf);
        _Py_END_SUPPRESS_IPH
#if defined _MSC_VER && _MSC_VER >= 1400 && defined(__STDC_SECURE_LIB__)
        /* VisualStudio .NET 2005 does this properly */
        if (buflen == 0 && errno == EINVAL) {
            PyErr_SetString(PyExc_ValueError, "Invalid format string");
            PyMem_Free(outbuf);
            break;
        }
#endif
        if (buflen > 0 || i >= 256 * fmtlen) {
            /* If the buffer is 256 times as long as the format,
               it's probably not failing for lack of room!
               More likely, the format yields an empty result,
               e.g. an empty format, or %Z when the timezone
               is unknown. */
#ifdef HAVE_WCSFTIME
            ret = PyUnicode_FromWideChar(outbuf, buflen);
#else
            ret = PyUnicode_DecodeLocaleAndSize(outbuf, buflen,
                                                "surrogateescape");
#endif
            PyMem_Free(outbuf);
            break;
        }
        PyMem_Free(outbuf);
    }
#ifdef HAVE_WCSFTIME
    PyMem_Free(format);
#else
    Py_DECREF(format);
#endif
    return ret;
}

#undef time_char
#undef format_time
PyDoc_STRVAR(strftime_doc,
"strftime(format[, tuple]) -> string\n\
\n\
Convert a time tuple to a string according to a format specification.\n\
See the library reference manual for formatting codes. When the time tuple\n\
is not present, current time as returned by localtime() is used.\n\
\n" STRFTIME_FORMAT_CODES);
#endif /* HAVE_STRFTIME */

static PyObject *
time_strptime(PyObject *self, PyObject *args)
{
    PyObject *strptime_module = PyImport_ImportModuleNoBlock("_strptime");
    PyObject *strptime_result;
    _Py_IDENTIFIER(_strptime_time);
    if (!strptime_module)
        return NULL;
    strptime_result = _PyObject_CallMethodId(strptime_module,
                                             &PyId__strptime_time, "O", args);
    Py_DECREF(strptime_module);
    return strptime_result;
}

PyDoc_STRVAR(strptime_doc,
"strptime(string, format) -> struct_time\n\
\n\
Parse a string to a time tuple according to a format specification.\n\
See the library reference manual for formatting codes (same as\n\
strftime()).\n\
\n" STRFTIME_FORMAT_CODES);

static PyObject *
_asctime(struct tm *timeptr)
{
    /* Inspired by Open Group reference implementation available at
     * http://pubs.opengroup.org/onlinepubs/009695399/functions/asctime.html */
    return PyUnicode_FromFormat(
        "%s %s%3d %.2d:%.2d:%.2d %d",
        kWeekdayNameShort[timeptr->tm_wday],
        kMonthNameShort[timeptr->tm_mon],
        timeptr->tm_mday, timeptr->tm_hour,
        timeptr->tm_min, timeptr->tm_sec,
        1900 + timeptr->tm_year);
}

static PyObject *
time_asctime(PyObject *self, PyObject *args)
{
    PyObject *tup = NULL;
    struct tm buf;
    if (!PyArg_UnpackTuple(args, "asctime", 0, 1, &tup))
        return NULL;
    if (tup == NULL) {
        time_t tt = Time(NULL);
        if (_PyTime_localtime(tt, &buf) != 0)
            return NULL;
    } else if (!gettmarg(tup, &buf) || !checktm(&buf))
        return NULL;
    return _asctime(&buf);
}

PyDoc_STRVAR(asctime_doc,
"asctime([tuple]) -> string\n\
\n\
Convert a time tuple to a string, e.g. 'Sat Jun 06 16:26:11 1998'.\n\
When the time tuple is not present, current time as returned by localtime()\n\
is used.");

static PyObject *
time_ctime(PyObject *self, PyObject *args)
{
    time_t tt;
    struct tm buf;
    if (!parse_time_t_args(args, "|O:ctime", &tt))
        return NULL;
    if (_PyTime_localtime(tt, &buf) != 0)
        return NULL;
    return _asctime(&buf);
}

PyDoc_STRVAR(ctime_doc,
"ctime(seconds) -> string\n\
\n\
Convert a time in seconds since the Epoch to a string in local time.\n\
This is equivalent to asctime(localtime(seconds)). When the time tuple is\n\
not present, current time as returned by localtime() is used.");

#ifdef HAVE_MKTIME
static PyObject *
time_mktime(PyObject *self, PyObject *tup)
{
    struct tm buf;
    time_t tt;
    if (!gettmarg(tup, &buf))
        return NULL;
#ifdef _AIX
    /* year < 1902 or year > 2037 */
    if (buf.tm_year < 2 || buf.tm_year > 137) {
        /* Issue #19748: On AIX, mktime() doesn't report overflow error for
         * timestamp < -2^31 or timestamp > 2**31-1. */
        PyErr_SetString(PyExc_OverflowError,
                        "mktime argument out of range");
        return NULL;
    }
#else
    buf.tm_wday = -1;  /* sentinel; original value ignored */
#endif
    tt = mktime(&buf);
    /* Return value of -1 does not necessarily mean an error, but tm_wday
     * cannot remain set to -1 if mktime succeeded. */
    if (tt == (time_t)(-1)
#ifndef _AIX
        /* Return value of -1 does not necessarily mean an error, but
         * tm_wday cannot remain set to -1 if mktime succeeded. */
        && buf.tm_wday == -1
#else
        /* on AIX, tm_wday is always sets, even on error */
#endif
       )
    {
        PyErr_SetString(PyExc_OverflowError,
                        "mktime argument out of range");
        return NULL;
    }
    return PyFloat_FromDouble((double)tt);
}

PyDoc_STRVAR(mktime_doc,
"mktime(tuple) -> floating point number\n\
\n\
Convert a time tuple in local time to seconds since the Epoch.\n\
Note that mktime(gmtime(0)) will not generally return zero for most\n\
time zones; instead the returned value will either be equal to that\n\
of the timezone or altzone attributes on the time module.");
#endif /* HAVE_MKTIME */

#ifdef HAVE_WORKING_TZSET
static int init_timezone(PyObject *module);

static PyObject *
time_tzset(PyObject *self, PyObject *unused)
{
    PyObject* m;
    m = PyImport_ImportModuleNoBlock("time");
    if (m == NULL) {
        return NULL;
    }
    tzset();
    /* Reset timezone, altzone, daylight and tzname */
    if (init_timezone(m) < 0) {
         return NULL;
    }
    Py_DECREF(m);
    if (PyErr_Occurred())
        return NULL;
    Py_INCREF(Py_None);
    return Py_None;
}

PyDoc_STRVAR(tzset_doc,
"tzset()\n\
\n\
Initialize, or reinitialize, the local timezone to the value stored in\n\
os.environ['TZ']. The TZ environment variable should be specified in\n\
standard Unix timezone format as documented in the tzset man page\n\
(eg. 'US/Eastern', 'Europe/Amsterdam'). Unknown timezones will silently\n\
fall back to UTC. If the TZ environment variable is not set, the local\n\
timezone is set to the systems best guess of wallclock time.\n\
Changing the TZ environment variable without calling tzset *may* change\n\
the local timezone used by methods such as localtime, but this behaviour\n\
should not be relied on.");
#endif /* HAVE_WORKING_TZSET */

static PyObject *
pymonotonic(_Py_clock_info_t *info)
{
    _PyTime_t t;
    double d;
    if (_PyTime_GetMonotonicClockWithInfo(&t, info) < 0) {
        assert(info != NULL);
        return NULL;
    }
    d = _PyTime_AsSecondsDouble(t);
    return PyFloat_FromDouble(d);
}

static PyObject *
time_monotonic(PyObject *self, PyObject *unused)
{
    return pymonotonic(NULL);
}

PyDoc_STRVAR(monotonic_doc,
"monotonic($module)\n\
\n\
Monotonic clock, cannot go backward, as float seconds.");

static PyObject *
time_monotonic_ns(PyObject *self, PyObject *unused)
{
    _PyTime_t t;
    if (_PyTime_GetMonotonicClockWithInfo(&t, 0)) return 0;
    return _PyTime_AsNanosecondsObject(t);
}

PyDoc_STRVAR(monotonic_ns_doc,
"monotonic_ns($module)\n\
--\n\n\
Monotonic clock, cannot go backward, as nanoseconds.");

static PyObject*
perf_counter(_Py_clock_info_t *info)
{
#ifdef WIN32_PERF_COUNTER
    return win_perf_counter(info);
#else
    return pymonotonic(info);
#endif
}

static PyObject *
time_perf_counter(PyObject *self, PyObject *unused)
{
    return perf_counter(NULL);
}

PyDoc_STRVAR(perf_counter_doc,
"perf_counter($module)\n\
--\n\n\
Performance counter for benchmarking, as float seconds.");

static PyObject *
time_perf_counter_ns(PyObject *self, PyObject *unused)
{
    _PyTime_t t;
    if (_PyTime_GetPerfCounterWithInfo(&t, 0)) return 0;
    return _PyTime_AsNanosecondsObject(t);
}

PyDoc_STRVAR(perf_counter_ns_doc,
"perf_counter_ns($module)\n\
--\n\n\
Performance counter for benchmarking as nanoseconds.");

static int
_PyTime_GetProcessTimeWithInfo(_PyTime_t *tp, _Py_clock_info_t *info)
{
    struct tms t;
    clock_t value;
    clockid_t clk_id;
    struct rusage ru;
    const char *function;
    struct timespec ts, res;
    struct NtFileTime creation_time, exit_time, kernel_time, user_time;
    if (IsWindows()) {
        if (!GetProcessTimes(GetCurrentProcess(),
                             &creation_time,
                             &exit_time,
                             &kernel_time,
                             &user_time)) {
            PyErr_SetFromWindowsErr(0);
            return -1;
        }
        if (info) {
            info->implementation = "GetProcessTimes()";
            info->resolution = 1e-7;
            info->monotonic = 1;
            info->adjustable = 0;
        }
        *tp = (ReadFileTime(kernel_time) + ReadFileTime(user_time)) * 100;
        return 0;
    }
    if (CLOCK_PROF != -1 || CLOCK_PROCESS_CPUTIME_ID != -1) {
        if (CLOCK_PROF != -1) {
            clk_id = CLOCK_PROF;
            function = "clock_gettime(CLOCK_PROF)";
        } else {
            clk_id = CLOCK_PROCESS_CPUTIME_ID;
            function = "clock_gettime(CLOCK_PROCESS_CPUTIME_ID)";
        }
        if (!clock_gettime(clk_id, &ts)) {
            if (info) {
                info->implementation = function;
                info->monotonic = 1;
                info->adjustable = 0;
                if (!clock_getres(clk_id, &res)) {
                    info->resolution = res.tv_sec + res.tv_nsec * 1e-9;
                } else {
                    info->resolution = 1e-9;
                }
            }
            if (_PyTime_FromTimespec(tp, &ts) < 0) {
                return -1;
            }
            return 0;
        }
    }
    if (!getrusage(RUSAGE_SELF, &ru)) {
        _PyTime_t utime, stime;
        if (info) {
            info->implementation = "getrusage(RUSAGE_SELF)";
            info->monotonic = 1;
            info->adjustable = 0;
            info->resolution = 1e-6;
        }
        if (_PyTime_FromTimeval(&utime, &ru.ru_utime) < 0) {
            return -1;
        }
        if (_PyTime_FromTimeval(&stime, &ru.ru_stime) < 0) {
            return -1;
        }
        *tp = utime + stime;
        return 0;
    }
    if (times(&t) != -1) {
        if (info) {
            info->implementation = "times()";
            info->monotonic = 1;
            info->adjustable = 0;
            info->resolution = 1. / CLK_TCK;
        }
        *tp = (t.tms_utime + t.tms_stime) * (1000000000ull / CLK_TCK);
        return 0;
    }
    /* Currently, Python 3 requires clock() to build: see issue #22624 */
    value = clock();
    if (value == (clock_t)-1) {
        PyErr_SetString(PyExc_RuntimeError,
                        "the processor time used is not available "
                        "or its value cannot be represented");
        return -1;
    }
    if (info) {
        info->implementation = "clock()";
        info->resolution = 1 / (double)CLOCKS_PER_SEC;
        info->monotonic = 1;
        info->adjustable = 0;
    }
    *tp = value * (1000000000ull / CLOCKS_PER_SEC);
    return 0;
}

static PyObject *
time_process_time(PyObject *self, PyObject *unused)
{
    _PyTime_t t;
    if (_PyTime_GetProcessTimeWithInfo(&t, 0)) return 0;
    return _PyFloat_FromPyTime(t);
}

PyDoc_STRVAR(process_time_doc,
"process_time($module)\n\
--\n\n\
Process time for profiling: sum of the kernel and user-space CPU time.\n\
Returned as float seconds.");

static PyObject *
time_process_time_ns(PyObject *self, PyObject *unused)
{
    _PyTime_t t;
    if (_PyTime_GetProcessTimeWithInfo(&t, 0)) return 0;
    return _PyTime_AsNanosecondsObject(t);
}

PyDoc_STRVAR(process_time_ns_doc,
"process_time_ns($module)\n\
--\n\n\
Process time for profiling returned as integer nanoseconds:\n\
sum of the kernel and user-space CPU time.");

static PyObject *
time_get_clock_info(PyObject *self, PyObject *args)
{
    char *name;
    _PyTime_t t;
    _Py_clock_info_t info;
    PyObject *obj = NULL, *dict, *ns;

    if (!PyArg_ParseTuple(args, "s:get_clock_info", &name))
        return NULL;

#ifdef Py_DEBUG
    info.implementation = NULL;
    info.monotonic = -1;
    info.adjustable = -1;
    info.resolution = -1.0;
#else
    info.implementation = "";
    info.monotonic = 0;
    info.adjustable = 0;
    info.resolution = 1.0;
#endif

    if (!strcmp(name, "clock")) {
        info.implementation = "clock()";
        info.resolution = 1 / (double)CLOCKS_PER_SEC;
        info.monotonic = 1;
        info.adjustable = 0;
    }
    else if (!strcmp(name, "time")) {
        if (_PyTime_GetSystemClockWithInfo(&t, &info) < 0) {
            return NULL;
        }
    }
    else if (!strcmp(name, "monotonic")) {
        if (_PyTime_GetMonotonicClockWithInfo(&t, &info) < 0) {
            return NULL;
        }
    }
    else if (!strcmp(name, "perf_counter")) {
        if (_PyTime_GetPerfCounterWithInfo(&t, &info) < 0) {
            return NULL;
        }
    }
    else if (!strcmp(name, "process_time")) {
        if (_PyTime_GetProcessTimeWithInfo(&t, &info) < 0) {
            return NULL;
        }
    }
    else {
        PyErr_SetString(PyExc_ValueError, "unknown clock");
        return NULL;
    }

    dict = PyDict_New();
    if (dict == NULL)
        return NULL;

    assert(info.implementation != NULL);
    obj = PyUnicode_FromString(info.implementation);
    if (obj == NULL)
        goto error;
    if (PyDict_SetItemString(dict, "implementation", obj) == -1)
        goto error;
    Py_CLEAR(obj);

    assert(info.monotonic != -1);
    obj = PyBool_FromLong(info.monotonic);
    if (obj == NULL)
        goto error;
    if (PyDict_SetItemString(dict, "monotonic", obj) == -1)
        goto error;
    Py_CLEAR(obj);

    assert(info.adjustable != -1);
    obj = PyBool_FromLong(info.adjustable);
    if (obj == NULL)
        goto error;
    if (PyDict_SetItemString(dict, "adjustable", obj) == -1)
        goto error;
    Py_CLEAR(obj);

    assert(info.resolution > 0.0);
    assert(info.resolution <= 1.0);
    obj = PyFloat_FromDouble(info.resolution);
    if (obj == NULL)
        goto error;
    if (PyDict_SetItemString(dict, "resolution", obj) == -1)
        goto error;
    Py_CLEAR(obj);

    ns = _PyNamespace_New(dict);
    Py_DECREF(dict);
    return ns;

error:
    Py_DECREF(dict);
    Py_XDECREF(obj);
    return NULL;
}

PyDoc_STRVAR(get_clock_info_doc,
"get_clock_info(name: str) -> dict\n\
\n\
Get information of the specified clock.");

static void
get_zone(char *zone, int n, struct tm *p)
{
#ifdef HAVE_STRUCT_TM_TM_ZONE
    strncpy(zone, p->tm_zone ? p->tm_zone : "   ", n);
#else
    tzset();
    strftime(zone, n, "%Z", p);
#endif
}

static time_t
get_gmtoff(time_t t, struct tm *p)
{
#ifdef HAVE_STRUCT_TM_TM_ZONE
    return p->tm_gmtoff;
#else
    return timegm(p) - t;
#endif
}

static int
init_timezone(PyObject *m)
{
    assert(!PyErr_Occurred());

    /* This code moved from PyInit_time wholesale to allow calling it from
    time_tzset. In the future, some parts of it can be moved back
    (for platforms that don't HAVE_WORKING_TZSET, when we know what they
    are), and the extraneous calls to tzset(3) should be removed.
    I haven't done this yet, as I don't want to change this code as
    little as possible when introducing the time.tzset and time.tzsetwall
    methods. This should simply be a method of doing the following once,
    at the top of this function and removing the call to tzset() from
    time_tzset():

        #ifdef HAVE_TZSET
        tzset()
        #endif

    And I'm lazy and hate C so nyer.
     */
#if defined(HAVE_TZNAME) && !defined(__GLIBC__) && !defined(__CYGWIN__)
    PyObject *otz0, *otz1;
    tzset();
    PyModule_AddIntConstant(m, "timezone", timezone);
#ifdef HAVE_ALTZONE
    PyModule_AddIntConstant(m, "altzone", altzone);
#else
    PyModule_AddIntConstant(m, "altzone", timezone-3600);
#endif
    PyModule_AddIntConstant(m, "daylight", daylight);
    otz0 = PyUnicode_DecodeLocale(tzname[0], "surrogateescape");
    if (otz0 == NULL) {
        return -1;
    }
    otz1 = PyUnicode_DecodeLocale(tzname[1], "surrogateescape");
    if (otz1 == NULL) {
        Py_DECREF(otz0);
        return -1;
    }
    PyObject *tzname_obj = Py_BuildValue("(NN)", otz0, otz1);
    if (tzname_obj == NULL) {
        return -1;
    }
    PyModule_AddObject(m, "tzname", tzname_obj);
#else /* !HAVE_TZNAME || __GLIBC__ || __CYGWIN__*/
    {
#define YEAR ((time_t)((365 * 24 + 6) * 3600))
        time_t t;
        struct tm p;
        time_t janzone_t, julyzone_t;
        char janname[10], julyname[10];
        t = (Time((time_t *)0) / YEAR) * YEAR;
        _PyTime_localtime(t, &p);
        get_zone(janname, 9, &p);
        janzone_t = -get_gmtoff(t, &p);
        janname[9] = '\0';
        t += YEAR/2;
        _PyTime_localtime(t, &p);
        get_zone(julyname, 9, &p);
        julyzone_t = -get_gmtoff(t, &p);
        julyname[9] = '\0';

        /* Sanity check, don't check for the validity of timezones.
           In practice, it should be more in range -12 hours .. +14 hours. */
#define MAX_TIMEZONE (48 * 3600)
        if (janzone_t < -MAX_TIMEZONE || janzone_t > MAX_TIMEZONE
            || julyzone_t < -MAX_TIMEZONE || julyzone_t > MAX_TIMEZONE)
        {
            PyErr_SetString(PyExc_RuntimeError, "invalid GMT offset");
            return -1;
        }
        int janzone = (int)janzone_t;
        int julyzone = (int)julyzone_t;

        if( janzone < julyzone ) {
            /* DST is reversed in the southern hemisphere */
            PyModule_AddIntConstant(m, "timezone", julyzone);
            PyModule_AddIntConstant(m, "altzone", janzone);
            PyModule_AddIntConstant(m, "daylight",
                                    janzone != julyzone);
            PyModule_AddObject(m, "tzname",
                               Py_BuildValue("(zz)",
                                             julyname, janname));
        } else {
            PyModule_AddIntConstant(m, "timezone", janzone);
            PyModule_AddIntConstant(m, "altzone", julyzone);
            PyModule_AddIntConstant(m, "daylight",
                                    janzone != julyzone);
            PyModule_AddObject(m, "tzname",
                               Py_BuildValue("(zz)",
                                             janname, julyname));
        }
    }
#ifdef __CYGWIN__
    tzset();
    PyModule_AddIntConstant(m, "timezone", _timezone);
    PyModule_AddIntConstant(m, "altzone", _timezone-3600);
    PyModule_AddIntConstant(m, "daylight", _daylight);
    PyModule_AddObject(m, "tzname",
                       Py_BuildValue("(zz)", _tzname[0], _tzname[1]));
#endif /* __CYGWIN__ */
#endif /* !HAVE_TZNAME || __GLIBC__ || __CYGWIN__*/

    if (PyErr_Occurred()) {
        return -1;
    }
    return 0;
}

static PyMethodDef time_methods[] = {
    {"time",            time_time, METH_NOARGS, time_doc},
    {"time_ns",         time_time_ns, METH_NOARGS, time_ns_doc},
#ifdef PYCLOCK
    {"clock",           time_clock, METH_NOARGS, clock_doc},
#endif
#ifdef HAVE_CLOCK_GETTIME
    {"clock_gettime",   time_clock_gettime, METH_VARARGS, clock_gettime_doc},
    {"clock_gettime_ns",time_clock_gettime_ns, METH_VARARGS, clock_gettime_ns_doc},
#endif
#ifdef HAVE_CLOCK_SETTIME
    {"clock_settime",   time_clock_settime, METH_VARARGS, clock_settime_doc},
#endif
#ifdef HAVE_CLOCK_GETRES
    {"clock_getres",    time_clock_getres, METH_VARARGS, clock_getres_doc},
#endif
    {"sleep",           time_sleep, METH_O, sleep_doc},
    {"gmtime",          time_gmtime, METH_VARARGS, gmtime_doc},
    {"localtime",       time_localtime, METH_VARARGS, localtime_doc},
    {"asctime",         time_asctime, METH_VARARGS, asctime_doc},
    {"ctime",           time_ctime, METH_VARARGS, ctime_doc},
#ifdef HAVE_MKTIME
    {"mktime",          time_mktime, METH_O, mktime_doc},
#endif
#ifdef HAVE_STRFTIME
    {"strftime",        time_strftime, METH_VARARGS, strftime_doc},
#endif
    {"strptime",        time_strptime, METH_VARARGS, strptime_doc},
#ifdef HAVE_WORKING_TZSET
    {"tzset",           time_tzset, METH_NOARGS, tzset_doc},
#endif
    {"monotonic",       time_monotonic, METH_NOARGS, monotonic_doc},
    {"monotonic_ns",    time_monotonic_ns, METH_NOARGS, monotonic_ns_doc},
    {"process_time",    time_process_time, METH_NOARGS, process_time_doc},
    {"process_time_ns", time_process_time_ns, METH_NOARGS, process_time_ns_doc},
    {"perf_counter",    time_perf_counter, METH_NOARGS, perf_counter_doc},
    {"perf_counter_ns", time_perf_counter_ns, METH_NOARGS, perf_counter_ns_doc},
    {"get_clock_info",  time_get_clock_info, METH_VARARGS, get_clock_info_doc},
    {NULL,              NULL}           /* sentinel */
};

PyDoc_STRVAR(module_doc,
"This module provides various functions to manipulate time values.\n\
\n\
There are two standard representations of time.  One is the number\n\
of seconds since the Epoch, in UTC (a.k.a. GMT).  It may be an integer\n\
or a floating point number (to represent fractions of seconds).\n\
The Epoch is system-defined; on Unix, it is generally January 1st, 1970.\n\
The actual value can be retrieved by calling gmtime(0).\n\
\n\
The other representation is a tuple of 9 integers giving local time.\n\
The tuple items are:\n\
  year (including century, e.g. 1998)\n\
  month (1-12)\n\
  day (1-31)\n\
  hours (0-23)\n\
  minutes (0-59)\n\
  seconds (0-59)\n\
  weekday (0-6, Monday is 0)\n\
  Julian day (day in the year, 1-366)\n\
  DST (Daylight Savings Time) flag (-1, 0 or 1)\n\
If the DST flag is 0, the time is given in the regular time zone;\n\
if it is 1, the time is given in the DST time zone;\n\
if it is -1, mktime() should guess based on the date and time.\n");

static struct PyModuleDef timemodule = {
    PyModuleDef_HEAD_INIT,
    "time",
    module_doc,
    -1,
    time_methods,
    NULL,
    NULL,
    NULL,
    NULL
};

PyMODINIT_FUNC
PyInit_time(void)
{
    PyObject *m;
    m = PyModule_Create(&timemodule);
    if (m == NULL)
        return NULL;
    /* Set, or reset, module variables like time.timezone */
    if (init_timezone(m) < 0) {
        return NULL;
    }
    PyModule_AddIntMacro(m, CLOCK_REALTIME);
    PyModule_AddIntMacro(m, CLOCK_MONOTONIC);
    if (CLOCK_MONOTONIC_RAW != -1) PyModule_AddIntMacro(m, CLOCK_MONOTONIC_RAW);
    if (CLOCK_PROCESS_CPUTIME_ID != -1) PyModule_AddIntMacro(m, CLOCK_PROCESS_CPUTIME_ID);
    if (CLOCK_THREAD_CPUTIME_ID != -1) PyModule_AddIntMacro(m, CLOCK_THREAD_CPUTIME_ID);
    if (!initialized) {
        if (PyStructSequence_InitType2(&StructTimeType,
                                       &struct_time_type_desc) < 0)
            return NULL;
    }
    Py_INCREF(&StructTimeType);
    PyModule_AddIntConstant(m, "_STRUCT_TM_ITEMS", 11);
    PyModule_AddObject(m, "struct_time", (PyObject*) &StructTimeType);
    initialized = 1;
    if (PyErr_Occurred()) {
        return NULL;
    }
    return m;
}

static PyObject*
floattime(_Py_clock_info_t *info)
{
    _PyTime_t t;
    double d;
    if (_PyTime_GetSystemClockWithInfo(&t, info) < 0) {
        assert(info != NULL);
        return NULL;
    }
    d = _PyTime_AsSecondsDouble(t);
    return PyFloat_FromDouble(d);
}


/* Implement pysleep() for various platforms.
   When interrupted (or when another error occurs), return -1 and
   set an exception; else return 0. */

static int
pysleep(_PyTime_t secs)
{
    _PyTime_t deadline, monotonic;
#ifndef MS_WINDOWS
    struct timeval timeout;
    struct timespec timeout2;
    int err = 0;
#else
    _PyTime_t millisecs;
    unsigned long ul_millis;
    uint32_t rc;
    int64_t hInterruptEvent;
#endif

    deadline = _PyTime_GetMonotonicClock() + secs;

    do {
#ifndef MS_WINDOWS
        Py_BEGIN_ALLOW_THREADS
#ifdef __COSMOPOLITAN__
        if (_PyTime_AsTimespec(secs, &timeout2) < 0)
            return -1;
        err = nanosleep(&timeout2, 0);
#else /* b/c xnu */
        if (_PyTime_AsTimeval(secs, &timeout, _PyTime_ROUND_CEILING) < 0)
            return -1;
        err = select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &timeout);
#endif
        Py_END_ALLOW_THREADS

        if (err == 0)
            break;

        if (errno != EINTR) {
            PyErr_SetFromErrno(PyExc_OSError);
            return -1;
        }
#else
        millisecs = _PyTime_AsMilliseconds(secs, _PyTime_ROUND_CEILING);
        if (millisecs > (double)ULONG_MAX) {
            PyErr_SetString(PyExc_OverflowError,
                            "sleep length is too large");
            return -1;
        }

        /* Allow sleep(0) to maintain win32 semantics, and as decreed
         * by Guido, only the main thread can be interrupted.
         */
        ul_millis = (unsigned long)millisecs;
        if (ul_millis == 0 || !_PyOS_IsMainThread()) {
            Py_BEGIN_ALLOW_THREADS
            Sleep(ul_millis);
            Py_END_ALLOW_THREADS
            break;
        }

        hInterruptEvent = _PyOS_SigintEvent();
        ResetEvent(hInterruptEvent);

        Py_BEGIN_ALLOW_THREADS
        rc = WaitForSingleObjectEx(hInterruptEvent, ul_millis, FALSE);
        Py_END_ALLOW_THREADS

        if (rc != WAIT_OBJECT_0)
            break;
#endif

        /* sleep was interrupted by SIGINT */
        if (PyErr_CheckSignals())
            return -1;

        monotonic = _PyTime_GetMonotonicClock();
        secs = deadline - monotonic;
        if (secs < 0)
            break;
        /* retry with the recomputed delay */
    } while (1);

    return 0;
}

#ifdef __aarch64__
_Section(".rodata.pytab.1 //")
#else
_Section(".rodata.pytab.1")
#endif
 const struct _inittab _PyImport_Inittab_time = {
    "time",
    PyInit_time,
};