Biomimetics MBED Library w/ Added Support for CAN3
Dependents: CAN_TEST SPIne_Plus_DYNO_SENSORS SPIne_Plus_v2 SPIne_Plus_Dyno_v2
platform/mbed_mktime.c
- Committer:
- adimmit
- Date:
- 2021-03-09
- Revision:
- 3:993b4d6ff61e
- Parent:
- 0:083111ae2a11
File content as of revision 3:993b4d6ff61e:
/* mbed Microcontroller Library * Copyright (c) 2017-2017 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "mbed_mktime.h" /* * time constants */ #define SECONDS_BY_MINUTES 60 #define MINUTES_BY_HOUR 60 #define SECONDS_BY_HOUR (SECONDS_BY_MINUTES * MINUTES_BY_HOUR) #define HOURS_BY_DAY 24 #define SECONDS_BY_DAY (SECONDS_BY_HOUR * HOURS_BY_DAY) /* * 2 dimensional array containing the number of seconds elapsed before a given * month. * The second index map to the month while the first map to the type of year: * - 0: non leap year * - 1: leap year */ static const uint32_t seconds_before_month[2][12] = { { 0, 31 * SECONDS_BY_DAY, (31 + 28) * SECONDS_BY_DAY, (31 + 28 + 31) * SECONDS_BY_DAY, (31 + 28 + 31 + 30) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30) * SECONDS_BY_DAY, }, { 0, 31 * SECONDS_BY_DAY, (31 + 29) * SECONDS_BY_DAY, (31 + 29 + 31) * SECONDS_BY_DAY, (31 + 29 + 31 + 30) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30 + 31 + 31) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31) * SECONDS_BY_DAY, (31 + 29 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 30) * SECONDS_BY_DAY, } }; bool _rtc_is_leap_year(int year) { /* * since in practice, the value manipulated by this algorithm lie in the * range [70 : 138], the algorith can be reduced to: year % 4. * The algorithm valid over the full range of value is: year = 1900 + year; if (year % 4) { return false; } else if (year % 100) { return true; } else if (year % 400) { return false; } return true; */ return (year) % 4 ? false : true; } time_t _rtc_mktime(const struct tm* time) { // partial check for the upper bound of the range // normalization might happen at the end of the function // this solution is faster than checking if the input is after the 19th of // january 2038 at 03:14:07. if ((time->tm_year < 70) || (time->tm_year > 138)) { return ((time_t) -1); } uint32_t result = time->tm_sec; result += time->tm_min * SECONDS_BY_MINUTES; result += time->tm_hour * SECONDS_BY_HOUR; result += (time->tm_mday - 1) * SECONDS_BY_DAY; result += seconds_before_month[_rtc_is_leap_year(time->tm_year)][time->tm_mon]; if (time->tm_year > 70) { // valid in the range [70:138] uint32_t count_of_leap_days = ((time->tm_year - 1) / 4) - (70 / 4); result += (((time->tm_year - 70) * 365) + count_of_leap_days) * SECONDS_BY_DAY; } if (result > INT32_MAX) { return (time_t) -1; } return result; } bool _rtc_localtime(time_t timestamp, struct tm* time_info) { if (((int32_t) timestamp) < 0) { return false; } time_info->tm_sec = timestamp % 60; timestamp = timestamp / 60; // timestamp in minutes time_info->tm_min = timestamp % 60; timestamp = timestamp / 60; // timestamp in hours time_info->tm_hour = timestamp % 24; timestamp = timestamp / 24; // timestamp in days; // compute the weekday // The 1st of January 1970 was a Thursday which is equal to 4 in the weekday // representation ranging from [0:6] time_info->tm_wday = (timestamp + 4) % 7; // years start at 70 time_info->tm_year = 70; while (true) { if (_rtc_is_leap_year(time_info->tm_year) && timestamp >= 366) { ++time_info->tm_year; timestamp -= 366; } else if (!_rtc_is_leap_year(time_info->tm_year) && timestamp >= 365) { ++time_info->tm_year; timestamp -= 365; } else { // the remaining days are less than a years break; } } time_info->tm_yday = timestamp; // convert days into seconds and find the current month timestamp *= SECONDS_BY_DAY; time_info->tm_mon = 11; bool leap = _rtc_is_leap_year(time_info->tm_year); for (uint32_t i = 0; i < 12; ++i) { if ((uint32_t) timestamp < seconds_before_month[leap][i]) { time_info->tm_mon = i - 1; break; } } // remove month from timestamp and compute the number of days. // note: unlike other fields, days are not 0 indexed. timestamp -= seconds_before_month[leap][time_info->tm_mon]; time_info->tm_mday = (timestamp / SECONDS_BY_DAY) + 1; return true; }