ChibiOS/os/various/chrtclib.c

130 lines
3.5 KiB
C

/*
ChibiOS - Copyright (C) 2014 Uladzimir Pylinsky aka barthess
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.
*/
/**
* @file chrtclib.c
* @brief Time conversion routines.
*
* @addtogroup chrtclib
* @{
*/
#include <time.h>
#include "chrtclib.h"
/**
* @brief Convert @p RTCDateTime to broken-down time structure.
*
* @param[in] timespec pointer to a @p RTCDateTime structure
* @param[out] timp pointer to a broken-down time structure
*
* @api
*/
void rtcConvertDateTimeToStructTm(const RTCDateTime *timespec,
struct tm *timp) {
uint32_t tmp;
timp->tm_year = timespec->year + (1980 - 1900);
timp->tm_mon = timespec->month - 1;
timp->tm_mday = timespec->day;
timp->tm_isdst = timespec->dstflag;
tmp = timespec->millisecond / 1000;
timp->tm_sec = tmp % 60;
tmp -= timp->tm_sec;
timp->tm_min = tmp % 3600;
tmp -= timp->tm_min * 60;
timp->tm_hour = tmp / 3600;
}
/**
* @brief Convert broken-down time structure to @p RTCDateTime.
*
* @param[in] timp pointer to a broken-down time structure
* @param[in] tv_msec milliseconds value
* @param[out] timespec pointer to a @p RTCDateTime structure
*
* @api
*/
void rtcConvertStructTmToDateTime(const struct tm *timp,
uint32_t tv_msec, RTCDateTime *timespec) {
timespec->year = timp->tm_year - (1980 - 1900);
timespec->month = timp->tm_mon + 1;
timespec->day = timp->tm_mday;
timespec->dayofweek = timp->tm_wday + 1;
if (-1 == timp->tm_isdst)
timespec->dstflag = 0; /* set zero if dst is unknown */
else
timespec->dstflag = timp->tm_isdst;
timespec->millisecond = tv_msec +
(timp->tm_hour * 3600 + timp->tm_min * 60 + timp->tm_sec) * 1000;
}
/*
* Lookup table for months' length
*/
static const uint8_t month_len[12] = {
31, 30, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
/**
* @brief Get current time in format suitable for usage in FAT file system.
* @note The information about day of week and DST is lost in DOS
* format, the second field loses its least significant bit.
*
* @param[out] timespec pointer to a @p RTCDateTime structure
* @return FAT date/time value.
*
* @api
*/
uint32_t rtcConvertDateTimeToFAT(const RTCDateTime *timespec) {
uint32_t fattime;
uint32_t sec, min, hour, day, month, tmp;
tmp = timespec->millisecond / 1000;
sec = tmp % 60;
min = (tmp - sec) % 3600;
hour = (tmp - sec - min * 60) / 3600;
day = timespec->day;
month = timespec->month;
/* handle DST flag */
if (1 == timespec->dstflag) {
hour += 1;
if (hour == 24) {
hour = 0;
day += 1;
if (day > month_len[month - 1]) {
day = 1;
month += 1;
}
}
}
fattime = sec >> 1;
fattime |= min << 5;
fattime |= hour << 11;
fattime |= day << 16;
fattime |= month << 21;
fattime |= timespec->year << 25;
return fattime;
}
/** @} */