File content as of revision 0:38a95c82b08c:

/*----------------------------------------------------------------------*
 * Arduino Timezone Library                                             *
 * Jack Christensen Mar 2012                                            *
 *                                                                      *
 * Arduino Timezone Library Copyright (C) 2018 by Jack Christensen and  *
 * licensed under GNU GPL v3.0, https://www.gnu.org/licenses/gpl.html   *
 *----------------------------------------------------------------------*/
#ifndef TIMEZONE_H_INCLUDED
#define TIMEZONE_H_INCLUDED

#include "mbed.h"

#define SECS_PER_MIN    60
#define SECS_PER_DAY    24*60*60

/*$off*/
// convenient constants for TimeChangeRules
enum week_t {Last, First, Second, Third, Fourth};
enum dow_t {Sun=1, Mon, Tue, Wed, Thu, Fri, Sat};
enum month_t {Jan=1, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec};
/*$on*/

// structure to describe rules for when daylight/summer time begins,

// or when standard time begins.
struct TimeChangeRule
{
    char    abbrev[6];  // five chars max
    uint8_t week;       // First, Second, Third, Fourth, or Last week of the month
    uint8_t dow;        // day of week, 1=Sun, 2=Mon, ... 7=Sat
    uint8_t month;      // 1=Jan, 2=Feb, ... 12=Dec
    uint8_t hour;       // 0-23
    int     offset;     // offset from UTC in minutes
};

class   Timezone
{
public:
    Timezone(TimeChangeRule dstStart, TimeChangeRule stdStart);
    Timezone(TimeChangeRule stdTime);
    Timezone(int address);
    time_t  toLocal(time_t utc);
    time_t  toLocal(time_t utc, TimeChangeRule ** tcr);
    time_t  toUTC(time_t local);
    bool    utcIsDST(time_t utc);
    bool    locIsDST(time_t local);
    void    setRules(TimeChangeRule dstStart, TimeChangeRule stdStart);
    void    readRules(int address);
    void    writeRules(int address);
private:
    void            calcTimeChanges(int yr);
    void            initTimeChanges();
    time_t          toTime_t(TimeChangeRule r, int yr);
    int             year(time_t seconds);
    TimeChangeRule  m_dst;      // rule for start of dst or summer time for any year
    TimeChangeRule  m_std;      // rule for start of standard time for any year
    time_t          m_dstUTC;   // dst start for given/current year, given in UTC
    time_t          m_stdUTC;   // std time start for given/current year, given in UTC
    time_t          m_dstLoc;   // dst start for given/current year, given in local time
    time_t          m_stdLoc;   // std time start for given/current year, given in local time
};

#endif // TIMEZONE_H_INCLUDED