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Diffstat (limited to 'ext/pybind11/include/pybind11/chrono.h')
| -rw-r--r-- | ext/pybind11/include/pybind11/chrono.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/ext/pybind11/include/pybind11/chrono.h b/ext/pybind11/include/pybind11/chrono.h new file mode 100644 index 000000000..2b37f56f1 --- /dev/null +++ b/ext/pybind11/include/pybind11/chrono.h @@ -0,0 +1,160 @@ +/* + pybind11/chrono.h: Transparent conversion between std::chrono and python's datetime + + Copyright (c) 2016 Trent Houliston <trent@houliston.me> and + Wenzel Jakob <wenzel.jakob@epfl.ch> + + All rights reserved. Use of this source code is governed by a + BSD-style license that can be found in the LICENSE file. +*/ + +#pragma once + +#include "pybind11.h" +#include <cmath> +#include <ctime> +#include <chrono> +#include <datetime.h> + +// Backport the PyDateTime_DELTA functions from Python3.3 if required +#ifndef PyDateTime_DELTA_GET_DAYS +#define PyDateTime_DELTA_GET_DAYS(o) (((PyDateTime_Delta*)o)->days) +#endif +#ifndef PyDateTime_DELTA_GET_SECONDS +#define PyDateTime_DELTA_GET_SECONDS(o) (((PyDateTime_Delta*)o)->seconds) +#endif +#ifndef PyDateTime_DELTA_GET_MICROSECONDS +#define PyDateTime_DELTA_GET_MICROSECONDS(o) (((PyDateTime_Delta*)o)->microseconds) +#endif + +NAMESPACE_BEGIN(pybind11) +NAMESPACE_BEGIN(detail) + +template <typename type> class duration_caster { +public: + typedef typename type::rep rep; + typedef typename type::period period; + + typedef std::chrono::duration<uint_fast32_t, std::ratio<86400>> days; + + bool load(handle src, bool) { + using namespace std::chrono; + + // Lazy initialise the PyDateTime import + if (!PyDateTimeAPI) { PyDateTime_IMPORT; } + + if (!src) return false; + // If invoked with datetime.delta object + if (PyDelta_Check(src.ptr())) { + value = type(duration_cast<duration<rep, period>>( + days(PyDateTime_DELTA_GET_DAYS(src.ptr())) + + seconds(PyDateTime_DELTA_GET_SECONDS(src.ptr())) + + microseconds(PyDateTime_DELTA_GET_MICROSECONDS(src.ptr())))); + return true; + } + // If invoked with a float we assume it is seconds and convert + else if (PyFloat_Check(src.ptr())) { + value = type(duration_cast<duration<rep, period>>(duration<double>(PyFloat_AsDouble(src.ptr())))); + return true; + } + else return false; + } + + // If this is a duration just return it back + static const std::chrono::duration<rep, period>& get_duration(const std::chrono::duration<rep, period> &src) { + return src; + } + + // If this is a time_point get the time_since_epoch + template <typename Clock> static std::chrono::duration<rep, period> get_duration(const std::chrono::time_point<Clock, std::chrono::duration<rep, period>> &src) { + return src.time_since_epoch(); + } + + static handle cast(const type &src, return_value_policy /* policy */, handle /* parent */) { + using namespace std::chrono; + + // Use overloaded function to get our duration from our source + // Works out if it is a duration or time_point and get the duration + auto d = get_duration(src); + + // Lazy initialise the PyDateTime import + if (!PyDateTimeAPI) { PyDateTime_IMPORT; } + + // Declare these special duration types so the conversions happen with the correct primitive types (int) + using dd_t = duration<int, std::ratio<86400>>; + using ss_t = duration<int, std::ratio<1>>; + using us_t = duration<int, std::micro>; + + return PyDelta_FromDSU(duration_cast<dd_t>(d).count(), + duration_cast<ss_t>(d % days(1)).count(), + duration_cast<us_t>(d % seconds(1)).count()); + } + + PYBIND11_TYPE_CASTER(type, _("datetime.timedelta")); +}; + +// This is for casting times on the system clock into datetime.datetime instances +template <typename Duration> class type_caster<std::chrono::time_point<std::chrono::system_clock, Duration>> { +public: + typedef std::chrono::time_point<std::chrono::system_clock, Duration> type; + bool load(handle src, bool) { + using namespace std::chrono; + + // Lazy initialise the PyDateTime import + if (!PyDateTimeAPI) { PyDateTime_IMPORT; } + + if (!src) return false; + if (PyDateTime_Check(src.ptr())) { + std::tm cal; + cal.tm_sec = PyDateTime_DATE_GET_SECOND(src.ptr()); + cal.tm_min = PyDateTime_DATE_GET_MINUTE(src.ptr()); + cal.tm_hour = PyDateTime_DATE_GET_HOUR(src.ptr()); + cal.tm_mday = PyDateTime_GET_DAY(src.ptr()); + cal.tm_mon = PyDateTime_GET_MONTH(src.ptr()) - 1; + cal.tm_year = PyDateTime_GET_YEAR(src.ptr()) - 1900; + cal.tm_isdst = -1; + + value = system_clock::from_time_t(std::mktime(&cal)) + microseconds(PyDateTime_DATE_GET_MICROSECOND(src.ptr())); + return true; + } + else return false; + } + + static handle cast(const std::chrono::time_point<std::chrono::system_clock, Duration> &src, return_value_policy /* policy */, handle /* parent */) { + using namespace std::chrono; + + // Lazy initialise the PyDateTime import + if (!PyDateTimeAPI) { PyDateTime_IMPORT; } + + std::time_t tt = system_clock::to_time_t(src); + // this function uses static memory so it's best to copy it out asap just in case + // otherwise other code that is using localtime may break this (not just python code) + std::tm localtime = *std::localtime(&tt); + + // Declare these special duration types so the conversions happen with the correct primitive types (int) + using us_t = duration<int, std::micro>; + + return PyDateTime_FromDateAndTime(localtime.tm_year + 1900, + localtime.tm_mon + 1, + localtime.tm_mday, + localtime.tm_hour, + localtime.tm_min, + localtime.tm_sec, + (duration_cast<us_t>(src.time_since_epoch() % seconds(1))).count()); + } + PYBIND11_TYPE_CASTER(type, _("datetime.datetime")); +}; + +// Other clocks that are not the system clock are not measured as datetime.datetime objects +// since they are not measured on calendar time. So instead we just make them timedeltas +// Or if they have passed us a time as a float we convert that +template <typename Clock, typename Duration> class type_caster<std::chrono::time_point<Clock, Duration>> +: public duration_caster<std::chrono::time_point<Clock, Duration>> { +}; + +template <typename Rep, typename Period> class type_caster<std::chrono::duration<Rep, Period>> +: public duration_caster<std::chrono::duration<Rep, Period>> { +}; + +NAMESPACE_END(detail) +NAMESPACE_END(pybind11) |