/* C implementation for the date/time type documented at

* https://www.zope.dev/Members/fdrake/DateTimeWiki/FrontPage

*/

/* bpo-35081: Defining this prevents including the C API capsule;

* internal versions of the Py*_Check macros which do not require

* the capsule are defined below */

#define _PY_DATETIME_IMPL

#ifndef Py_BUILD_CORE_BUILTIN

# define Py_BUILD_CORE_MODULE 1

#endif

#include "Python.h"

#include "pycore_long.h" // _PyLong_GetOne()

#include "pycore_object.h" // _PyObject_Init()

#include "pycore_time.h" // _PyTime_ObjectToTime_t()

#include "datetime.h"

#include <time.h>

#ifdef MS_WINDOWS

# include <winsock2.h> /* struct timeval */

#endif

#define PyDate_Check(op) PyObject_TypeCheck(op, &PyDateTime_DateType)

#define PyDate_CheckExact(op) Py_IS_TYPE(op, &PyDateTime_DateType)

#define PyDateTime_Check(op) PyObject_TypeCheck(op, &PyDateTime_DateTimeType)

#define PyDateTime_CheckExact(op) Py_IS_TYPE(op, &PyDateTime_DateTimeType)

#define PyTime_Check(op) PyObject_TypeCheck(op, &PyDateTime_TimeType)

#define PyTime_CheckExact(op) Py_IS_TYPE(op, &PyDateTime_TimeType)

#define PyDelta_Check(op) PyObject_TypeCheck(op, &PyDateTime_DeltaType)

#define PyDelta_CheckExact(op) Py_IS_TYPE(op, &PyDateTime_DeltaType)

#define PyTZInfo_Check(op) PyObject_TypeCheck(op, &PyDateTime_TZInfoType)

#define PyTZInfo_CheckExact(op) Py_IS_TYPE(op, &PyDateTime_TZInfoType)

#define PyTimezone_Check(op) PyObject_TypeCheck(op, &PyDateTime_TimeZoneType)

typedef struct {

/* Conversion factors. */

PyObject *us_per_ms; // 1_000

PyObject *us_per_second; // 1_000_000

PyObject *us_per_minute; // 1e6 * 60 as Python int

PyObject *us_per_hour; // 1e6 * 3600 as Python int

PyObject *us_per_day; // 1e6 * 3600 * 24 as Python int

PyObject *us_per_week; // 1e6 * 3600 * 24 * 7 as Python int

PyObject *seconds_per_day; // 3600 * 24 as Python int

/* The interned UTC timezone instance */

PyObject *utc;

/* The interned Unix epoch datetime instance */

PyObject *epoch;

} datetime_state;

static datetime_state _datetime_global_state;

#define STATIC_STATE() (&_datetime_global_state)

/* We require that C int be at least 32 bits, and use int virtually

* everywhere. In just a few cases we use a temp long, where a Python

* API returns a C long. In such cases, we have to ensure that the

* final result fits in a C int (this can be an issue on 64-bit boxes).

*/

#if SIZEOF_INT < 4

# error "_datetime.c requires that C int have at least 32 bits"

#endif

#define MINYEAR 1

#define MAXYEAR 9999

#define MAXORDINAL 3652059 /* date(9999,12,31).toordinal() */

/* Nine decimal digits is easy to communicate, and leaves enough room

* so that two delta days can be added w/o fear of overflowing a signed

* 32-bit int, and with plenty of room left over to absorb any possible

* carries from adding seconds.

*/

#define MAX_DELTA_DAYS 999999999

/* Rename the long macros in datetime.h to more reasonable short names. */

#define GET_YEAR PyDateTime_GET_YEAR

#define GET_MONTH PyDateTime_GET_MONTH

#define GET_DAY PyDateTime_GET_DAY

#define DATE_GET_HOUR PyDateTime_DATE_GET_HOUR

#define DATE_GET_MINUTE PyDateTime_DATE_GET_MINUTE

#define DATE_GET_SECOND PyDateTime_DATE_GET_SECOND

#define DATE_GET_MICROSECOND PyDateTime_DATE_GET_MICROSECOND

#define DATE_GET_FOLD PyDateTime_DATE_GET_FOLD

/* Date accessors for date and datetime. */

#define SET_YEAR(o, v) (((o)->data[0] = ((v) & 0xff00) >> 8), \

((o)->data[1] = ((v) & 0x00ff)))

#define SET_MONTH(o, v) (PyDateTime_GET_MONTH(o) = (v))

#define SET_DAY(o, v) (PyDateTime_GET_DAY(o) = (v))

/* Date/Time accessors for datetime. */

#define DATE_SET_HOUR(o, v) (PyDateTime_DATE_GET_HOUR(o) = (v))

#define DATE_SET_MINUTE(o, v) (PyDateTime_DATE_GET_MINUTE(o) = (v))

#define DATE_SET_SECOND(o, v) (PyDateTime_DATE_GET_SECOND(o) = (v))

#define DATE_SET_MICROSECOND(o, v) \

(((o)->data[7] = ((v) & 0xff0000) >> 16), \

((o)->data[8] = ((v) & 0x00ff00) >> 8), \

((o)->data[9] = ((v) & 0x0000ff)))

#define DATE_SET_FOLD(o, v) (PyDateTime_DATE_GET_FOLD(o) = (v))

/* Time accessors for time. */

#define TIME_GET_HOUR PyDateTime_TIME_GET_HOUR

#define TIME_GET_MINUTE PyDateTime_TIME_GET_MINUTE

#define TIME_GET_SECOND PyDateTime_TIME_GET_SECOND

#define TIME_GET_MICROSECOND PyDateTime_TIME_GET_MICROSECOND

#define TIME_GET_FOLD PyDateTime_TIME_GET_FOLD

#define TIME_SET_HOUR(o, v) (PyDateTime_TIME_GET_HOUR(o) = (v))

#define TIME_SET_MINUTE(o, v) (PyDateTime_TIME_GET_MINUTE(o) = (v))

#define TIME_SET_SECOND(o, v) (PyDateTime_TIME_GET_SECOND(o) = (v))

#define TIME_SET_MICROSECOND(o, v) \

(((o)->data[3] = ((v) & 0xff0000) >> 16), \

((o)->data[4] = ((v) & 0x00ff00) >> 8), \

((o)->data[5] = ((v) & 0x0000ff)))

#define TIME_SET_FOLD(o, v) (PyDateTime_TIME_GET_FOLD(o) = (v))

/* Delta accessors for timedelta. */

#define GET_TD_DAYS(o) (((PyDateTime_Delta *)(o))->days)

#define GET_TD_SECONDS(o) (((PyDateTime_Delta *)(o))->seconds)

#define GET_TD_MICROSECONDS(o) (((PyDateTime_Delta *)(o))->microseconds)

#define SET_TD_DAYS(o, v) ((o)->days = (v))

#define SET_TD_SECONDS(o, v) ((o)->seconds = (v))

#define SET_TD_MICROSECONDS(o, v) ((o)->microseconds = (v))

#define HASTZINFO _PyDateTime_HAS_TZINFO

#define GET_TIME_TZINFO PyDateTime_TIME_GET_TZINFO

#define GET_DT_TZINFO PyDateTime_DATE_GET_TZINFO

/* M is a char or int claiming to be a valid month. The macro is equivalent

* to the two-sided Python test

* 1 <= M <= 12

*/

#define MONTH_IS_SANE(M) ((unsigned int)(M) - 1 < 12)

/* Forward declarations. */

static PyTypeObject PyDateTime_DateType;

static PyTypeObject PyDateTime_DateTimeType;

static PyTypeObject PyDateTime_DeltaType;

static PyTypeObject PyDateTime_IsoCalendarDateType;

static PyTypeObject PyDateTime_TimeType;

static PyTypeObject PyDateTime_TZInfoType;

static PyTypeObject PyDateTime_TimeZoneType;

static int check_tzinfo_subclass(PyObject *p);

/*[clinic input]

module datetime

class datetime.datetime "PyDateTime_DateTime *" "&PyDateTime_DateTimeType"

class datetime.date "PyDateTime_Date *" "&PyDateTime_DateType"

class datetime.time "PyDateTime_Time *" "&PyDateTime_TimeType"

class datetime.IsoCalendarDate "PyDateTime_IsoCalendarDate *" "&PyDateTime_IsoCalendarDateType"

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=6f65a48dd22fa40f]*/

#include "clinic/_datetimemodule.c.h"

/* ---------------------------------------------------------------------------

* Math utilities.

*/

/* k = i+j overflows iff k differs in sign from both inputs,

* iff k^i has sign bit set and k^j has sign bit set,

* iff (k^i)&(k^j) has sign bit set.

*/

#define SIGNED_ADD_OVERFLOWED(RESULT, I, J) \

((((RESULT) ^ (I)) & ((RESULT) ^ (J))) < 0)

/* Compute Python divmod(x, y), returning the quotient and storing the

* remainder into *r. The quotient is the floor of x/y, and that's

* the real point of this. C will probably truncate instead (C99

* requires truncation; C89 left it implementation-defined).

* Simplification: we *require* that y > 0 here. That's appropriate

* for all the uses made of it. This simplifies the code and makes

* the overflow case impossible (divmod(LONG_MIN, -1) is the only

* overflow case).

*/

static int

divmod(int x, int y, int *r)

{

int quo;

assert(y > 0);

quo = x / y;

*r = x - quo * y;

if (*r < 0) {

--quo;

*r += y;

}

assert(0 <= *r && *r < y);

return quo;

}

/* Nearest integer to m / n for integers m and n. Half-integer results

* are rounded to even.

*/

static PyObject *

divide_nearest(PyObject *m, PyObject *n)

{

PyObject *result;

PyObject *temp;

temp = _PyLong_DivmodNear(m, n);

if (temp == NULL)

return NULL;

result = Py_NewRef(PyTuple_GET_ITEM(temp, 0));

Py_DECREF(temp);

return result;

}

/* ---------------------------------------------------------------------------

* General calendrical helper functions

*/

/* For each month ordinal in 1..12, the number of days in that month,

* and the number of days before that month in the same year. These

* are correct for non-leap years only.

*/

static const int _days_in_month[] = {

0, /* unused; this vector uses 1-based indexing */

31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31

};

static const int _days_before_month[] = {

0, /* unused; this vector uses 1-based indexing */

0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334

};

/* year -> 1 if leap year, else 0. */

static int

is_leap(int year)

{

/* Cast year to unsigned. The result is the same either way, but

* C can generate faster code for unsigned mod than for signed

* mod (especially for % 4 -- a good compiler should just grab

* the last 2 bits when the LHS is unsigned).

*/

const unsigned int ayear = (unsigned int)year;

return ayear % 4 == 0 && (ayear % 100 != 0 || ayear % 400 == 0);

}

/* year, month -> number of days in that month in that year */

static int

days_in_month(int year, int month)

{

assert(month >= 1);

assert(month <= 12);

if (month == 2 && is_leap(year))

return 29;

else

return _days_in_month[month];

}

/* year, month -> number of days in year preceding first day of month */

static int

days_before_month(int year, int month)

{

int days;

assert(month >= 1);

assert(month <= 12);

days = _days_before_month[month];

if (month > 2 && is_leap(year))

++days;

return days;

}

/* year -> number of days before January 1st of year. Remember that we

* start with year 1, so days_before_year(1) == 0.

*/

static int

days_before_year(int year)

{

int y = year - 1;

/* This is incorrect if year <= 0; we really want the floor

* here. But so long as MINYEAR is 1, the smallest year this

* can see is 1.

*/

assert (year >= 1);

return y*365 + y/4 - y/100 + y/400;

}

/* Number of days in 4, 100, and 400 year cycles. That these have

* the correct values is asserted in the module init function.

*/

#define DI4Y 1461 /* days_before_year(5); days in 4 years */

#define DI100Y 36524 /* days_before_year(101); days in 100 years */

#define DI400Y 146097 /* days_before_year(401); days in 400 years */

/* ordinal -> year, month, day, considering 01-Jan-0001 as day 1. */

static void

ord_to_ymd(int ordinal, int *year, int *month, int *day)

{

int n, n1, n4, n100, n400, leapyear, preceding;

/* ordinal is a 1-based index, starting at 1-Jan-1. The pattern of

* leap years repeats exactly every 400 years. The basic strategy is

* to find the closest 400-year boundary at or before ordinal, then

* work with the offset from that boundary to ordinal. Life is much

* clearer if we subtract 1 from ordinal first -- then the values

* of ordinal at 400-year boundaries are exactly those divisible

* by DI400Y:

*

* D M Y n n-1

* -- --- ---- ---------- ----------------

* 31 Dec -400 -DI400Y -DI400Y -1

* 1 Jan -399 -DI400Y +1 -DI400Y 400-year boundary

* ...

* 30 Dec 000 -1 -2

* 31 Dec 000 0 -1

* 1 Jan 001 1 0 400-year boundary

* 2 Jan 001 2 1

* 3 Jan 001 3 2

* ...

* 31 Dec 400 DI400Y DI400Y -1

* 1 Jan 401 DI400Y +1 DI400Y 400-year boundary

*/

assert(ordinal >= 1);

--ordinal;

n400 = ordinal / DI400Y;

n = ordinal % DI400Y;

*year = n400 * 400 + 1;

/* Now n is the (non-negative) offset, in days, from January 1 of

* year, to the desired date. Now compute how many 100-year cycles

* precede n.

* Note that it's possible for n100 to equal 4! In that case 4 full

* 100-year cycles precede the desired day, which implies the

* desired day is December 31 at the end of a 400-year cycle.

*/

n100 = n / DI100Y;

n = n % DI100Y;

/* Now compute how many 4-year cycles precede it. */

n4 = n / DI4Y;

n = n % DI4Y;

/* And now how many single years. Again n1 can be 4, and again

* meaning that the desired day is December 31 at the end of the

* 4-year cycle.

*/

n1 = n / 365;

n = n % 365;

*year += n100 * 100 + n4 * 4 + n1;

if (n1 == 4 || n100 == 4) {

assert(n == 0);

*year -= 1;

*month = 12;

*day = 31;

return;

}

/* Now the year is correct, and n is the offset from January 1. We

* find the month via an estimate that's either exact or one too

* large.

*/

leapyear = n1 == 3 && (n4 != 24 || n100 == 3);

assert(leapyear == is_leap(*year));

*month = (n + 50) >> 5;

preceding = (_days_before_month[*month] + (*month > 2 && leapyear));

if (preceding > n) {

/* estimate is too large */

*month -= 1;

preceding -= days_in_month(*year, *month);

}

n -= preceding;

assert(0 <= n);

assert(n < days_in_month(*year, *month));

*day = n + 1;

}

/* year, month, day -> ordinal, considering 01-Jan-0001 as day 1. */

static int

ymd_to_ord(int year, int month, int day)

{

return days_before_year(year) + days_before_month(year, month) + day;

}

/* Day of week, where Monday==0, ..., Sunday==6. 1/1/1 was a Monday. */

static int

weekday(int year, int month, int day)

{

return (ymd_to_ord(year, month, day) + 6) % 7;

}

/* Ordinal of the Monday starting week 1 of the ISO year. Week 1 is the

* first calendar week containing a Thursday.

*/

static int

iso_week1_monday(int year)

{

int first_day = ymd_to_ord(year, 1, 1); /* ord of 1/1 */

/* 0 if 1/1 is a Monday, 1 if a Tue, etc. */

int first_weekday = (first_day + 6) % 7;

/* ordinal of closest Monday at or before 1/1 */

int week1_monday = first_day - first_weekday;

if (first_weekday > 3) /* if 1/1 was Fri, Sat, Sun */

week1_monday += 7;

return week1_monday;

}

static int

iso_to_ymd(const int iso_year, const int iso_week, const int iso_day,

int *year, int *month, int *day) {

if (iso_week <= 0 || iso_week >= 53) {

int out_of_range = 1;

if (iso_week == 53) {

// ISO years have 53 weeks in it on years starting with a Thursday

// and on leap years starting on Wednesday

int first_weekday = weekday(iso_year, 1, 1);

if (first_weekday == 3 || (first_weekday == 2 && is_leap(iso_year))) {

out_of_range = 0;

}

}

if (out_of_range) {

return -2;

}

}

if (iso_day <= 0 || iso_day >= 8) {

return -3;

}

// Convert (Y, W, D) to (Y, M, D) in-place

int day_1 = iso_week1_monday(iso_year);

int day_offset = (iso_week - 1)*7 + iso_day - 1;

ord_to_ymd(day_1 + day_offset, year, month, day);

return 0;

}

/* ---------------------------------------------------------------------------

* Range checkers.

*/

/* Check that -MAX_DELTA_DAYS <= days <= MAX_DELTA_DAYS. If so, return 0.

* If not, raise OverflowError and return -1.

*/

static int

check_delta_day_range(int days)

{

if (-MAX_DELTA_DAYS <= days && days <= MAX_DELTA_DAYS)

return 0;

PyErr_Format(PyExc_OverflowError,

"days=%d; must have magnitude <= %d",

days, MAX_DELTA_DAYS);

return -1;

}

/* Check that date arguments are in range. Return 0 if they are. If they

* aren't, raise ValueError and return -1.

*/

static int

check_date_args(int year, int month, int day)

{

if (year < MINYEAR || year > MAXYEAR) {

PyErr_Format(PyExc_ValueError, "year %i is out of range", year);

return -1;

}

if (month < 1 || month > 12) {

PyErr_SetString(PyExc_ValueError,

"month must be in 1..12");

return -1;

}

if (day < 1 || day > days_in_month(year, month)) {

PyErr_SetString(PyExc_ValueError,

"day is out of range for month");

return -1;

}

return 0;

}

/* Check that time arguments are in range. Return 0 if they are. If they

* aren't, raise ValueError and return -1.

*/

static int

check_time_args(int h, int m, int s, int us, int fold)

{

if (h < 0 || h > 23) {

PyErr_SetString(PyExc_ValueError,

"hour must be in 0..23");

return -1;

}

if (m < 0 || m > 59) {

PyErr_SetString(PyExc_ValueError,

"minute must be in 0..59");

return -1;

}

if (s < 0 || s > 59) {

PyErr_SetString(PyExc_ValueError,

"second must be in 0..59");

return -1;

}

if (us < 0 || us > 999999) {

PyErr_SetString(PyExc_ValueError,

"microsecond must be in 0..999999");

return -1;

}

if (fold != 0 && fold != 1) {

PyErr_SetString(PyExc_ValueError,

"fold must be either 0 or 1");

return -1;

}

return 0;

}

/* ---------------------------------------------------------------------------

* Normalization utilities.

*/

/* One step of a mixed-radix conversion. A "hi" unit is equivalent to

* factor "lo" units. factor must be > 0. If *lo is less than 0, or

* at least factor, enough of *lo is converted into "hi" units so that

* 0 <= *lo < factor. The input values must be such that int overflow

* is impossible.

*/

static void

normalize_pair(int *hi, int *lo, int factor)

{

assert(factor > 0);

assert(lo != hi);

if (*lo < 0 || *lo >= factor) {

const int num_hi = divmod(*lo, factor, lo);

const int new_hi = *hi + num_hi;

assert(! SIGNED_ADD_OVERFLOWED(new_hi, *hi, num_hi));

*hi = new_hi;

}

assert(0 <= *lo && *lo < factor);

}

/* Fiddle days (d), seconds (s), and microseconds (us) so that

* 0 <= *s < 24*3600

* 0 <= *us < 1000000

* The input values must be such that the internals don't overflow.

* The way this routine is used, we don't get close.

*/

static void

normalize_d_s_us(int *d, int *s, int *us)

{

if (*us < 0 || *us >= 1000000) {

normalize_pair(s, us, 1000000);

/* |s| can't be bigger than about

* |original s| + |original us|/1000000 now.

*/

}

if (*s < 0 || *s >= 24*3600) {

normalize_pair(d, s, 24*3600);

/* |d| can't be bigger than about

* |original d| +

* (|original s| + |original us|/1000000) / (24*3600) now.

*/

}

assert(0 <= *s && *s < 24*3600);

assert(0 <= *us && *us < 1000000);

}

/* Fiddle years (y), months (m), and days (d) so that

* 1 <= *m <= 12

* 1 <= *d <= days_in_month(*y, *m)

* The input values must be such that the internals don't overflow.

* The way this routine is used, we don't get close.

*/

static int

normalize_y_m_d(int *y, int *m, int *d)

{

int dim; /* # of days in month */

/* In actual use, m is always the month component extracted from a

* date/datetime object. Therefore it is always in [1, 12] range.

*/

assert(1 <= *m && *m <= 12);

/* Now only day can be out of bounds (year may also be out of bounds

* for a datetime object, but we don't care about that here).

* If day is out of bounds, what to do is arguable, but at least the

* method here is principled and explainable.

*/

dim = days_in_month(*y, *m);

if (*d < 1 || *d > dim) {

/* Move day-1 days from the first of the month. First try to

* get off cheap if we're only one day out of range

* (adjustments for timezone alone can't be worse than that).

*/

if (*d == 0) {

--*m;

if (*m > 0)

*d = days_in_month(*y, *m);

else {

--*y;

*m = 12;

*d = 31;

}

}

else if (*d == dim + 1) {

/* move forward a day */

++*m;

*d = 1;

if (*m > 12) {

*m = 1;

++*y;

}

}

else {

int ordinal = ymd_to_ord(*y, *m, 1) +

*d - 1;

if (ordinal < 1 || ordinal > MAXORDINAL) {

goto error;

} else {

ord_to_ymd(ordinal, y, m, d);

return 0;

}

}

}

assert(*m > 0);

assert(*d > 0);

if (MINYEAR <= *y && *y <= MAXYEAR)

return 0;

error:

PyErr_SetString(PyExc_OverflowError,

"date value out of range");

return -1;

}

/* Fiddle out-of-bounds months and days so that the result makes some kind

* of sense. The parameters are both inputs and outputs. Returns < 0 on

* failure, where failure means the adjusted year is out of bounds.

*/

static int

normalize_date(int *year, int *month, int *day)

{

return normalize_y_m_d(year, month, day);

}

/* Force all the datetime fields into range. The parameters are both

* inputs and outputs. Returns < 0 on error.

*/

static int

normalize_datetime(int *year, int *month, int *day,

int *hour, int *minute, int *second,

int *microsecond)

{

normalize_pair(second, microsecond, 1000000);

normalize_pair(minute, second, 60);

normalize_pair(hour, minute, 60);

normalize_pair(day, hour, 24);

return normalize_date(year, month, day);

}

/* ---------------------------------------------------------------------------

* Basic object allocation: tp_alloc implementations. These allocate

* Python objects of the right size and type, and do the Python object-

* initialization bit. If there's not enough memory, they return NULL after

* setting MemoryError. All data members remain uninitialized trash.

*

* We abuse the tp_alloc "nitems" argument to communicate whether a tzinfo

* member is needed. This is ugly, imprecise, and possibly insecure.

* tp_basicsize for the time and datetime types is set to the size of the

* struct that has room for the tzinfo member, so subclasses in Python will

* allocate enough space for a tzinfo member whether or not one is actually

* needed. That's the "ugly and imprecise" parts. The "possibly insecure"

* part is that PyType_GenericAlloc() (which subclasses in Python end up

* using) just happens today to effectively ignore the nitems argument

* when tp_itemsize is 0, which it is for these type objects. If that

* changes, perhaps the callers of tp_alloc slots in this file should

* be changed to force a 0 nitems argument unless the type being allocated

* is a base type implemented in this file (so that tp_alloc is time_alloc

* or datetime_alloc below, which know about the nitems abuse).

*/

static PyObject *

time_alloc(PyTypeObject *type, Py_ssize_t aware)

{

size_t size = aware ? sizeof(PyDateTime_Time) : sizeof(_PyDateTime_BaseTime);

PyObject *self = (PyObject *)PyObject_Malloc(size);

if (self == NULL) {

return PyErr_NoMemory();

}

_PyObject_Init(self, type);

return self;

}

static PyObject *

datetime_alloc(PyTypeObject *type, Py_ssize_t aware)

{

size_t size = aware ? sizeof(PyDateTime_DateTime) : sizeof(_PyDateTime_BaseDateTime);

PyObject *self = (PyObject *)PyObject_Malloc(size);

if (self == NULL) {

return PyErr_NoMemory();

}

_PyObject_Init(self, type);

return self;

}

/* ---------------------------------------------------------------------------

* Helpers for setting object fields. These work on pointers to the

* appropriate base class.

*/

/* For date and datetime. */

static void

set_date_fields(PyDateTime_Date *self, int y, int m, int d)

{

self->hashcode = -1;

SET_YEAR(self, y);

SET_MONTH(self, m);

SET_DAY(self, d);

}

/* ---------------------------------------------------------------------------

* String parsing utilities and helper functions

*/

static unsigned char

is_digit(const char c) {

return ((unsigned int)(c - '0')) < 10;

}

static const char *

parse_digits(const char *ptr, int *var, size_t num_digits)

{

for (size_t i = 0; i < num_digits; ++i) {

unsigned int tmp = (unsigned int)(*(ptr++) - '0');

if (tmp > 9) {

return NULL;

}

*var *= 10;

*var += (signed int)tmp;

}

return ptr;

}

static int

parse_isoformat_date(const char *dtstr, const size_t len, int *year, int *month, int *day)

{

/* Parse the date components of the result of date.isoformat()

*

* Return codes:

* 0: Success

* -1: Failed to parse date component

* -2: Inconsistent date separator usage

* -3: Failed to parse ISO week.

* -4: Failed to parse ISO day.

* -5, -6: Failure in iso_to_ymd

*/

const char *p = dtstr;

p = parse_digits(p, year, 4);

if (NULL == p) {

return -1;

}

const unsigned char uses_separator = (*p == '-');

if (uses_separator) {

++p;

}

if(*p == 'W') {

// This is an isocalendar-style date string

p++;

int iso_week = 0;

int iso_day = 0;

p = parse_digits(p, &iso_week, 2);

if (NULL == p) {

return -3;

}

assert(p > dtstr);

if ((size_t)(p - dtstr) < len) {

if (uses_separator && *(p++) != '-') {

return -2;

}

p = parse_digits(p, &iso_day, 1);

if (NULL == p) {

return -4;

}

} else {

iso_day = 1;

}

int rv = iso_to_ymd(*year, iso_week, iso_day, year, month, day);

if (rv) {

return -3 + rv;

} else {

return 0;

}

}

p = parse_digits(p, month, 2);

if (NULL == p) {

return -1;

}

if (uses_separator && *(p++) != '-') {

return -2;

}

p = parse_digits(p, day, 2);

if (p == NULL) {

return -1;

}

return 0;

}

static int

parse_hh_mm_ss_ff(const char *tstr, const char *tstr_end, int *hour,

int *minute, int *second, int *microsecond)

{

*hour = *minute = *second = *microsecond = 0;

const char *p = tstr;

const char *p_end = tstr_end;

int *vals[3] = {hour, minute, second};

// This is initialized to satisfy an erroneous compiler warning.

unsigned char has_separator = 1;

// Parse [HH[:?MM[:?SS]]]

for (size_t i = 0; i < 3; ++i) {

p = parse_digits(p, vals[i], 2);

if (NULL == p) {

return -3;

}

char c = *(p++);

if (i == 0) {

has_separator = (c == ':');

}

if (p >= p_end) {

return c != '\0';

}

else if (has_separator && (c == ':')) {

continue;

}

else if (c == '.' || c == ',') {

break;

} else if (!has_separator) {

--p;

} else {

return -4; // Malformed time separator

}

}

// Parse fractional components

size_t len_remains = p_end - p;

size_t to_parse = len_remains;

if (len_remains >= 6) {

to_parse = 6;

}

p = parse_digits(p, microsecond, to_parse);

if (NULL == p) {

return -3;

}

static int correction[] = {

100000, 10000, 1000, 100, 10

};

if (to_parse < 6) {

*microsecond *= correction[to_parse-1];

}

while (is_digit(*p)){

++p; // skip truncated digits

}

// Return 1 if it's not the end of the string

return *p != '\0';

}

static int

parse_isoformat_time(const char *dtstr, size_t dtlen, int *hour, int *minute,

int *second, int *microsecond, int *tzoffset,

int *tzmicrosecond)

{

// Parse the time portion of a datetime.isoformat() string

//

// Return codes:

// 0: Success (no tzoffset)

// 1: Success (with tzoffset)

// -3: Failed to parse time component

// -4: Failed to parse time separator

// -5: Malformed timezone string

const char *p = dtstr;

const char *p_end = dtstr + dtlen;

const char *tzinfo_pos = p;

do {

if (*tzinfo_pos == 'Z' || *tzinfo_pos == '+' || *tzinfo_pos == '-') {

break;

}

} while (++tzinfo_pos < p_end);

int rv = parse_hh_mm_ss_ff(dtstr, tzinfo_pos, hour, minute, second,

microsecond);

if (rv < 0) {

return rv;

}

else if (tzinfo_pos == p_end) {

// We know that there's no time zone, so if there's stuff at the

// end of the string it's an error.

if (rv == 1) {

return -5;

}

else {

return 0;

}

}

// Special case UTC / Zulu time.

if (*tzinfo_pos == 'Z') {

*tzoffset = 0;

*tzmicrosecond = 0;

if (*(tzinfo_pos + 1) != '\0') {

return -5;

} else {

return 1;

}

}

int tzsign = (*tzinfo_pos == '-') ? -1 : 1;

tzinfo_pos++;

int tzhour = 0, tzminute = 0, tzsecond = 0;

rv = parse_hh_mm_ss_ff(tzinfo_pos, p_end, &tzhour, &tzminute, &tzsecond,

tzmicrosecond);

*tzoffset = tzsign * ((tzhour * 3600) + (tzminute * 60) + tzsecond);

*tzmicrosecond *= tzsign;

return rv ? -5 : 1;

}

/* ---------------------------------------------------------------------------

* Create various objects, mostly without range checking.

*/

/* Create a date instance with no range checking. */

static PyObject *

new_date_ex(int year, int month, int day, PyTypeObject *type)

{

PyDateTime_Date *self;

if (check_date_args(year, month, day) < 0) {

return NULL;

}

self = (PyDateTime_Date *)(type->tp_alloc(type, 0));

if (self != NULL)

set_date_fields(self, year, month, day);

return (PyObject *)self;

}

#define new_date(year, month, day) \

new_date_ex(year, month, day, &PyDateTime_DateType)

// Forward declaration

static PyObject *

new_datetime_ex(int, int, int, int, int, int, int, PyObject *, PyTypeObject *);

/* Create date instance with no range checking, or call subclass constructor */

static PyObject *

new_date_subclass_ex(int year, int month, int day, PyObject *cls)

{

PyObject *result;

// We have "fast path" constructors for two subclasses: date and datetime

if ((PyTypeObject *)cls == &PyDateTime_DateType) {

result = new_date_ex(year, month, day, (PyTypeObject *)cls);

}

else if ((PyTypeObject *)cls == &PyDateTime_DateTimeType) {

result = new_datetime_ex(year, month, day, 0, 0, 0, 0, Py_None,

(PyTypeObject *)cls);

}

else {

result = PyObject_CallFunction(cls, "iii", year, month, day);

}