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bacnet_stack/ports/bsd/datetime-init.c
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Steve Karg fdd49f1791 Feature/make pretty apps and ports (#80)
* Added pretty-apps and pretty-ports make targets

* pretty-fied apps folder C files

* Pretty-fied ports folder C and H files

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>
2020-04-30 10:13:11 -05:00

90 lines
2.7 KiB
C

/**
* @file
* @author Steve Karg
* @date 2009
* @brief System time library header file.
*
* @section DESCRIPTION
*
* This library provides functions for getting and setting the system time.
*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <time.h>
#include "bacport.h"
#include "bacnet/datetime.h"
/**
* @brief Get the date, time, timezone, and UTC offset from system
* @param utc_time - the BACnet Date and Time structure to hold UTC time
* @param local_time - the BACnet Date and Time structure to hold local time
* @param utc_offset_minutes - number of minutes offset from UTC
* For example, -6*60 represents 6.00 hours behind UTC/GMT
* @param true if DST is enabled and active
* @return true if local time was retrieved
*/
bool datetime_local(BACNET_DATE *bdate,
BACNET_TIME *btime,
int16_t *utc_offset_minutes,
bool *dst_active)
{
bool status = false;
struct tm *tblock = NULL;
struct timeval tv;
if (gettimeofday(&tv, NULL) == 0) {
tblock = (struct tm *)localtime((const time_t *)&tv.tv_sec);
}
if (tblock) {
status = true;
/** struct tm
* int tm_sec Seconds [0,60].
* int tm_min Minutes [0,59].
* int tm_hour Hour [0,23].
* int tm_mday Day of month [1,31].
* int tm_mon Month of year [0,11].
* int tm_year Years since 1900.
* int tm_wday Day of week [0,6] (Sunday =0).
* int tm_yday Day of year [0,365].
* int tm_isdst Daylight Savings flag.
*/
datetime_set_date(bdate, (uint16_t)tblock->tm_year + 1900,
(uint8_t)tblock->tm_mon + 1, (uint8_t)tblock->tm_mday);
datetime_set_time(btime, (uint8_t)tblock->tm_hour,
(uint8_t)tblock->tm_min, (uint8_t)tblock->tm_sec,
(uint8_t)(tv.tv_usec / 10000));
if (dst_active) {
/* The value of tm_isdst is:
- positive if Daylight Saving Time is in effect,
- 0 if Daylight Saving Time is not in effect, and
- negative if the information is not available. */
if (tblock->tm_isdst > 0) {
*dst_active = true;
} else {
*dst_active = false;
}
}
/* note: timezone is declared in <time.h> stdlib. */
if (utc_offset_minutes) {
/* timezone is set to the difference, in seconds,
between Coordinated Universal Time (UTC) and
local standard time */
*utc_offset_minutes = timezone / 60;
}
}
return status;
}
/**
* initialize the date time
*/
void datetime_init(void)
{
/* nothing to do */
}