Andrew Boyson / clock

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Dependents:   oldheating gps motorhome heating

time.c@26:0421132e6eaf, 2018-01-25 (annotated)

Committer:
andrewboyson
Date:
Thu Jan 25 07:54:54 2018 +0000
Revision:
26:0421132e6eaf
Changed ticks from a count of ns to a fixed fraction of 30bits. This makes it much easier to convert to and from NTP and time_t

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 26:0421132e6eaf 1 #include <stdlib.h>
andrewboyson 26:0421132e6eaf 2 #include <time.h>
andrewboyson 26:0421132e6eaf 3 #include <stdio.h>
andrewboyson 26:0421132e6eaf 4 #include <string.h>
andrewboyson 26:0421132e6eaf 5 #include <stdbool.h>
andrewboyson 26:0421132e6eaf 6
andrewboyson 26:0421132e6eaf 7 #define STD_OFFSET 0
andrewboyson 26:0421132e6eaf 8 #define DST_OFFSET 1
andrewboyson 26:0421132e6eaf 9
andrewboyson 26:0421132e6eaf 10 static bool isLeapYear(int year)
andrewboyson 26:0421132e6eaf 11 {
andrewboyson 26:0421132e6eaf 12 year += 1900;
andrewboyson 26:0421132e6eaf 13 bool leapYear = !(year & 0x3);
andrewboyson 26:0421132e6eaf 14 if (year >= 2100)
andrewboyson 26:0421132e6eaf 15 {
andrewboyson 26:0421132e6eaf 16 if (year % 100 == 0) leapYear = false;
andrewboyson 26:0421132e6eaf 17 if (year % 400 == 0) leapYear = true;
andrewboyson 26:0421132e6eaf 18 }
andrewboyson 26:0421132e6eaf 19 return leapYear;
andrewboyson 26:0421132e6eaf 20
andrewboyson 26:0421132e6eaf 21 }
andrewboyson 26:0421132e6eaf 22 static int monthLength(int year, int month)
andrewboyson 26:0421132e6eaf 23 {
andrewboyson 26:0421132e6eaf 24 static char monthlengths[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
andrewboyson 26:0421132e6eaf 25 int daysInMonth = monthlengths[month];
andrewboyson 26:0421132e6eaf 26 if (month == 1 && isLeapYear(year)) daysInMonth++; //February is month 1 of months 0 to 11
andrewboyson 26:0421132e6eaf 27 return daysInMonth;
andrewboyson 26:0421132e6eaf 28 }
andrewboyson 26:0421132e6eaf 29 static bool isDst(int year, int month, int dayOfMonth, int dayOfWeek, int hours)
andrewboyson 26:0421132e6eaf 30 {
andrewboyson 26:0421132e6eaf 31 //Find the last Sunday in the month
andrewboyson 26:0421132e6eaf 32 int lastDayOfMonth = monthLength(year, month);
andrewboyson 26:0421132e6eaf 33 int daysToEndOfMonth = lastDayOfMonth - dayOfMonth;
andrewboyson 26:0421132e6eaf 34 int dayOfWeekOfLastDayOfMonth = (dayOfWeek + daysToEndOfMonth) % 7;
andrewboyson 26:0421132e6eaf 35 int lastSundayDayOfMonth = lastDayOfMonth - dayOfWeekOfLastDayOfMonth;
andrewboyson 26:0421132e6eaf 36
andrewboyson 26:0421132e6eaf 37 //Check each month
andrewboyson 26:0421132e6eaf 38 if (month <= 1) return false; //Jan, Feb
andrewboyson 26:0421132e6eaf 39 if (month == 2) //Mar - DST true after 1am UTC on the last Sunday in March
andrewboyson 26:0421132e6eaf 40 {
andrewboyson 26:0421132e6eaf 41 if (dayOfMonth < lastSundayDayOfMonth) return false;
andrewboyson 26:0421132e6eaf 42 if (dayOfMonth == lastSundayDayOfMonth) return hours >= 1;
andrewboyson 26:0421132e6eaf 43 if (dayOfMonth > lastSundayDayOfMonth) return true;
andrewboyson 26:0421132e6eaf 44 }
andrewboyson 26:0421132e6eaf 45 if (month >= 3 && month <= 8) return true; //Apr, May, Jun, Jul, Aug, Sep
andrewboyson 26:0421132e6eaf 46 if (month == 9) //Oct - DST false after 1am UTC on the last Sunday in October
andrewboyson 26:0421132e6eaf 47 {
andrewboyson 26:0421132e6eaf 48 if (dayOfMonth < lastSundayDayOfMonth) return true;
andrewboyson 26:0421132e6eaf 49 if (dayOfMonth == lastSundayDayOfMonth) return hours < 1;
andrewboyson 26:0421132e6eaf 50 if (dayOfMonth > lastSundayDayOfMonth) return false;
andrewboyson 26:0421132e6eaf 51 }
andrewboyson 26:0421132e6eaf 52 if (month >= 10) return false; //Nov, Dec
andrewboyson 26:0421132e6eaf 53 return false;
andrewboyson 26:0421132e6eaf 54 }
andrewboyson 26:0421132e6eaf 55 static void calculateDayOfYearAndWeek(int thisYear, int thisMonth, int thisMonthDay, int* pDayOfYear, int* pDayOfWeek)
andrewboyson 26:0421132e6eaf 56 {
andrewboyson 26:0421132e6eaf 57 int dayOfYear = 0; //1 Jan is day 0
andrewboyson 26:0421132e6eaf 58 int dayOfWeek = 4; //1 Jan 1970 is a Thursday
andrewboyson 26:0421132e6eaf 59
andrewboyson 26:0421132e6eaf 60 //Add days of each whole year
andrewboyson 26:0421132e6eaf 61 for (int y = 70; y < thisYear; y++)
andrewboyson 26:0421132e6eaf 62 {
andrewboyson 26:0421132e6eaf 63 int lengthOfYear = isLeapYear(y) ? 366 : 365;
andrewboyson 26:0421132e6eaf 64 dayOfWeek += lengthOfYear;
andrewboyson 26:0421132e6eaf 65 }
andrewboyson 26:0421132e6eaf 66
andrewboyson 26:0421132e6eaf 67 //Add days of each whole month
andrewboyson 26:0421132e6eaf 68 for (int m = 0; m < thisMonth; m++)
andrewboyson 26:0421132e6eaf 69 {
andrewboyson 26:0421132e6eaf 70 int lengthOfMonth = monthLength(thisYear, m);
andrewboyson 26:0421132e6eaf 71 dayOfYear += lengthOfMonth;
andrewboyson 26:0421132e6eaf 72 dayOfWeek += lengthOfMonth;
andrewboyson 26:0421132e6eaf 73 }
andrewboyson 26:0421132e6eaf 74
andrewboyson 26:0421132e6eaf 75 //Add days of part month
andrewboyson 26:0421132e6eaf 76 thisMonthDay--; //thisMonthDay is 01 to 31 where we need 00 to 30
andrewboyson 26:0421132e6eaf 77 dayOfYear += thisMonthDay;
andrewboyson 26:0421132e6eaf 78 dayOfWeek += thisMonthDay;
andrewboyson 26:0421132e6eaf 79
andrewboyson 26:0421132e6eaf 80 //Update the day of year and day of week parts of the struct tm
andrewboyson 26:0421132e6eaf 81 *pDayOfYear = dayOfYear; // 0 --> 365
andrewboyson 26:0421132e6eaf 82 *pDayOfWeek = dayOfWeek % 7; // 0 --> 6
andrewboyson 26:0421132e6eaf 83 }
andrewboyson 26:0421132e6eaf 84 void TimeIncrement(struct tm* ptm)
andrewboyson 26:0421132e6eaf 85 {
andrewboyson 26:0421132e6eaf 86 ptm->tm_sec++;
andrewboyson 26:0421132e6eaf 87 if (ptm->tm_sec > 59)
andrewboyson 26:0421132e6eaf 88 {
andrewboyson 26:0421132e6eaf 89 ptm->tm_sec = 0;
andrewboyson 26:0421132e6eaf 90 ptm->tm_min++;
andrewboyson 26:0421132e6eaf 91 }
andrewboyson 26:0421132e6eaf 92 if (ptm->tm_min > 59)
andrewboyson 26:0421132e6eaf 93 {
andrewboyson 26:0421132e6eaf 94 ptm->tm_min = 0;
andrewboyson 26:0421132e6eaf 95 ptm->tm_hour++;
andrewboyson 26:0421132e6eaf 96 }
andrewboyson 26:0421132e6eaf 97 if (ptm->tm_hour > 23)
andrewboyson 26:0421132e6eaf 98 {
andrewboyson 26:0421132e6eaf 99 ptm->tm_hour = 0;
andrewboyson 26:0421132e6eaf 100 ptm->tm_wday++;
andrewboyson 26:0421132e6eaf 101 if (ptm->tm_wday > 6) ptm->tm_wday = 0;
andrewboyson 26:0421132e6eaf 102 ptm->tm_yday++;
andrewboyson 26:0421132e6eaf 103 ptm->tm_mday++;
andrewboyson 26:0421132e6eaf 104 if (ptm->tm_mday > monthLength(ptm->tm_year, ptm->tm_mon))
andrewboyson 26:0421132e6eaf 105 {
andrewboyson 26:0421132e6eaf 106 ptm->tm_mon++;
andrewboyson 26:0421132e6eaf 107 if (ptm->tm_mon > 11)
andrewboyson 26:0421132e6eaf 108 {
andrewboyson 26:0421132e6eaf 109 ptm->tm_year++;
andrewboyson 26:0421132e6eaf 110 ptm->tm_yday = 0;
andrewboyson 26:0421132e6eaf 111 ptm->tm_mon = 0;
andrewboyson 26:0421132e6eaf 112 }
andrewboyson 26:0421132e6eaf 113 ptm->tm_mday = 1;
andrewboyson 26:0421132e6eaf 114 }
andrewboyson 26:0421132e6eaf 115 }
andrewboyson 26:0421132e6eaf 116 }
andrewboyson 26:0421132e6eaf 117 static void normalise(int* pHours, int* pDayOfWeek, int* pDayOfMonth, int* pMonth, int * pDayOfYear, int* pYear)
andrewboyson 26:0421132e6eaf 118 {
andrewboyson 26:0421132e6eaf 119 if (*pHours > 23)
andrewboyson 26:0421132e6eaf 120 {
andrewboyson 26:0421132e6eaf 121 *pHours -= 24;
andrewboyson 26:0421132e6eaf 122 ++*pDayOfWeek;
andrewboyson 26:0421132e6eaf 123 if (*pDayOfWeek > 6) *pDayOfWeek = 0;
andrewboyson 26:0421132e6eaf 124 ++*pDayOfYear;
andrewboyson 26:0421132e6eaf 125 ++*pDayOfMonth;
andrewboyson 26:0421132e6eaf 126 if (*pDayOfMonth > monthLength(*pYear, *pMonth))
andrewboyson 26:0421132e6eaf 127 {
andrewboyson 26:0421132e6eaf 128 ++*pMonth;
andrewboyson 26:0421132e6eaf 129 if (*pMonth > 11)
andrewboyson 26:0421132e6eaf 130 {
andrewboyson 26:0421132e6eaf 131 ++*pYear;
andrewboyson 26:0421132e6eaf 132 *pDayOfYear = 0;
andrewboyson 26:0421132e6eaf 133 *pMonth = 0;
andrewboyson 26:0421132e6eaf 134 }
andrewboyson 26:0421132e6eaf 135 *pDayOfMonth = 1;
andrewboyson 26:0421132e6eaf 136 }
andrewboyson 26:0421132e6eaf 137 }
andrewboyson 26:0421132e6eaf 138
andrewboyson 26:0421132e6eaf 139 if (*pHours < 0)
andrewboyson 26:0421132e6eaf 140 {
andrewboyson 26:0421132e6eaf 141 *pHours += 24;
andrewboyson 26:0421132e6eaf 142 --*pDayOfWeek;
andrewboyson 26:0421132e6eaf 143 if (*pDayOfWeek < 0) *pDayOfWeek = 6;
andrewboyson 26:0421132e6eaf 144 --*pDayOfYear;
andrewboyson 26:0421132e6eaf 145 --*pDayOfMonth;
andrewboyson 26:0421132e6eaf 146 if (*pDayOfMonth < 1)
andrewboyson 26:0421132e6eaf 147 {
andrewboyson 26:0421132e6eaf 148 --*pMonth;
andrewboyson 26:0421132e6eaf 149 if (*pMonth < 0)
andrewboyson 26:0421132e6eaf 150 {
andrewboyson 26:0421132e6eaf 151 --*pYear;
andrewboyson 26:0421132e6eaf 152 *pDayOfYear = isLeapYear(*pYear) ? 365 : 364;
andrewboyson 26:0421132e6eaf 153 *pMonth = 11;
andrewboyson 26:0421132e6eaf 154 }
andrewboyson 26:0421132e6eaf 155 *pDayOfMonth = monthLength(*pYear, *pMonth);
andrewboyson 26:0421132e6eaf 156 }
andrewboyson 26:0421132e6eaf 157 }
andrewboyson 26:0421132e6eaf 158 }
andrewboyson 26:0421132e6eaf 159 static void addYears(int* pYear, int* pDayOfWeek, int* pDaysLeft)
andrewboyson 26:0421132e6eaf 160 {
andrewboyson 26:0421132e6eaf 161 while(1)
andrewboyson 26:0421132e6eaf 162 {
andrewboyson 26:0421132e6eaf 163 //See if it is a leap year
andrewboyson 26:0421132e6eaf 164 int leapYear = isLeapYear(*pYear);
andrewboyson 26:0421132e6eaf 165
andrewboyson 26:0421132e6eaf 166 //Find the number of days in this year
andrewboyson 26:0421132e6eaf 167 int daysInYear = leapYear ? 366 : 365;
andrewboyson 26:0421132e6eaf 168
andrewboyson 26:0421132e6eaf 169 //Stop if this is the final year
andrewboyson 26:0421132e6eaf 170 if (*pDaysLeft < daysInYear) break;
andrewboyson 26:0421132e6eaf 171
andrewboyson 26:0421132e6eaf 172 //Calculate the current day of the week at the start of the year
andrewboyson 26:0421132e6eaf 173 *pDayOfWeek += leapYear ? 2 : 1;
andrewboyson 26:0421132e6eaf 174 if (*pDayOfWeek >= 7) *pDayOfWeek -= 7;
andrewboyson 26:0421132e6eaf 175
andrewboyson 26:0421132e6eaf 176 //Move on to the next year
andrewboyson 26:0421132e6eaf 177 *pDaysLeft -= daysInYear;
andrewboyson 26:0421132e6eaf 178 ++*pYear;
andrewboyson 26:0421132e6eaf 179 }
andrewboyson 26:0421132e6eaf 180 }
andrewboyson 26:0421132e6eaf 181 static void addMonths(int year, int* pMonth, int* pDaysLeft)
andrewboyson 26:0421132e6eaf 182 {
andrewboyson 26:0421132e6eaf 183 while(1)
andrewboyson 26:0421132e6eaf 184 {
andrewboyson 26:0421132e6eaf 185 int daysInMonth = monthLength(year, *pMonth);
andrewboyson 26:0421132e6eaf 186
andrewboyson 26:0421132e6eaf 187 //Stop if this is the last month
andrewboyson 26:0421132e6eaf 188 if (*pDaysLeft < daysInMonth) break;
andrewboyson 26:0421132e6eaf 189
andrewboyson 26:0421132e6eaf 190 //Move onto next month
andrewboyson 26:0421132e6eaf 191 *pDaysLeft -= daysInMonth;
andrewboyson 26:0421132e6eaf 192 ++*pMonth;
andrewboyson 26:0421132e6eaf 193 }
andrewboyson 26:0421132e6eaf 194 }
andrewboyson 26:0421132e6eaf 195 static void timeToTm(time_t t, struct tm* ptm, bool local)
andrewboyson 26:0421132e6eaf 196 {
andrewboyson 26:0421132e6eaf 197 //Extract the seconds, minutes, hours and days from the time_t t
andrewboyson 26:0421132e6eaf 198 div_t divres;
andrewboyson 26:0421132e6eaf 199 divres = div( t, 60); int seconds = divres.rem;
andrewboyson 26:0421132e6eaf 200 divres = div(divres.quot, 60); int minutes = divres.rem;
andrewboyson 26:0421132e6eaf 201 divres = div(divres.quot, 24); int hours = divres.rem;
andrewboyson 26:0421132e6eaf 202 int daysLeft = divres.quot;
andrewboyson 26:0421132e6eaf 203
andrewboyson 26:0421132e6eaf 204 //Add a year at a time while there is more than a year of days left
andrewboyson 26:0421132e6eaf 205 int year = 70; //Unix epoch is 1970
andrewboyson 26:0421132e6eaf 206 int dayOfWeek = 4; //1 Jan 1970 is a Thursday
andrewboyson 26:0421132e6eaf 207 addYears(&year, &dayOfWeek, &daysLeft);
andrewboyson 26:0421132e6eaf 208
andrewboyson 26:0421132e6eaf 209 //Days left contains the days left from the start (1 Jan) of the current year
andrewboyson 26:0421132e6eaf 210 int dayOfYear = daysLeft;
andrewboyson 26:0421132e6eaf 211 dayOfWeek += daysLeft;
andrewboyson 26:0421132e6eaf 212 dayOfWeek %= 7;
andrewboyson 26:0421132e6eaf 213
andrewboyson 26:0421132e6eaf 214 //Add a month at a time while there is more than a month of days left
andrewboyson 26:0421132e6eaf 215 int month = 0;
andrewboyson 26:0421132e6eaf 216 addMonths(year, &month, &daysLeft);
andrewboyson 26:0421132e6eaf 217
andrewboyson 26:0421132e6eaf 218 //Days left contains the days left from the start (1st) of the current month
andrewboyson 26:0421132e6eaf 219 int dayOfMonth = daysLeft + 1;
andrewboyson 26:0421132e6eaf 220
andrewboyson 26:0421132e6eaf 221 //Deal with local time offsets
andrewboyson 26:0421132e6eaf 222 int dst;
andrewboyson 26:0421132e6eaf 223 if (local)
andrewboyson 26:0421132e6eaf 224 {
andrewboyson 26:0421132e6eaf 225 //Work out if Daylight Saving Time applies
andrewboyson 26:0421132e6eaf 226 dst = isDst(year, month, dayOfMonth, dayOfWeek, hours);
andrewboyson 26:0421132e6eaf 227
andrewboyson 26:0421132e6eaf 228 //Adjust for the timezone
andrewboyson 26:0421132e6eaf 229 hours += dst ? DST_OFFSET : STD_OFFSET;
andrewboyson 26:0421132e6eaf 230 normalise(&hours, &dayOfWeek, &dayOfMonth, &month, &dayOfYear, &year);
andrewboyson 26:0421132e6eaf 231 }
andrewboyson 26:0421132e6eaf 232 else
andrewboyson 26:0421132e6eaf 233 {
andrewboyson 26:0421132e6eaf 234 dst = -1;
andrewboyson 26:0421132e6eaf 235 }
andrewboyson 26:0421132e6eaf 236
andrewboyson 26:0421132e6eaf 237 //Set up the broken time TM structure
andrewboyson 26:0421132e6eaf 238 ptm->tm_sec = seconds; // 00 --> 59
andrewboyson 26:0421132e6eaf 239 ptm->tm_min = minutes; // 00 --> 59
andrewboyson 26:0421132e6eaf 240 ptm->tm_hour = hours; // 00 --> 23
andrewboyson 26:0421132e6eaf 241 ptm->tm_mday = dayOfMonth; // 01 --> 31
andrewboyson 26:0421132e6eaf 242 ptm->tm_mon = month; // 00 --> 11
andrewboyson 26:0421132e6eaf 243 ptm->tm_year = year; // Years since 1900
andrewboyson 26:0421132e6eaf 244 ptm->tm_wday = dayOfWeek; // 0 --> 6 where 0 == Sunday
andrewboyson 26:0421132e6eaf 245 ptm->tm_yday = dayOfYear; // 0 --> 365
andrewboyson 26:0421132e6eaf 246 ptm->tm_isdst = dst; // +ve if DST, 0 if not DSTime, -ve if the information is not available. Note that 'true' evaluates to +1.
andrewboyson 26:0421132e6eaf 247 }
andrewboyson 26:0421132e6eaf 248 void TimeToTmUtc(time_t time, struct tm* ptm)
andrewboyson 26:0421132e6eaf 249 {
andrewboyson 26:0421132e6eaf 250 timeToTm(time, ptm, false);
andrewboyson 26:0421132e6eaf 251 }
andrewboyson 26:0421132e6eaf 252 void TimeToTmLocal(time_t time, struct tm* ptm)
andrewboyson 26:0421132e6eaf 253 {
andrewboyson 26:0421132e6eaf 254 timeToTm(time, ptm, true);
andrewboyson 26:0421132e6eaf 255 }
andrewboyson 26:0421132e6eaf 256 time_t TimeFromTmUtc(struct tm* ptm)
andrewboyson 26:0421132e6eaf 257 {
andrewboyson 26:0421132e6eaf 258 int days = 0;
andrewboyson 26:0421132e6eaf 259
andrewboyson 26:0421132e6eaf 260 for (int y = 70; y < ptm->tm_year; y++) days += isLeapYear(y) ? 366 : 365;
andrewboyson 26:0421132e6eaf 261
andrewboyson 26:0421132e6eaf 262 days += ptm->tm_yday;
andrewboyson 26:0421132e6eaf 263
andrewboyson 26:0421132e6eaf 264 return days * 86400 +
andrewboyson 26:0421132e6eaf 265 ptm->tm_hour * 3600 +
andrewboyson 26:0421132e6eaf 266 ptm->tm_min * 60 +
andrewboyson 26:0421132e6eaf 267 ptm->tm_sec;
andrewboyson 26:0421132e6eaf 268 }
andrewboyson 26:0421132e6eaf 269 int TimePeriodBetween(struct tm* ptmLater, struct tm* ptmEarlier)
andrewboyson 26:0421132e6eaf 270 {
andrewboyson 26:0421132e6eaf 271 int days = 0;
andrewboyson 26:0421132e6eaf 272
andrewboyson 26:0421132e6eaf 273 if (ptmLater->tm_year > ptmEarlier->tm_year) for (int y = ptmEarlier->tm_year; y < ptmLater->tm_year; y++) days += isLeapYear(y) ? 366 : 365;
andrewboyson 26:0421132e6eaf 274 else for (int y = ptmEarlier->tm_year; y > ptmLater->tm_year; y--) days -= isLeapYear(y) ? 366 : 365;
andrewboyson 26:0421132e6eaf 275
andrewboyson 26:0421132e6eaf 276 days += ptmLater->tm_yday - ptmEarlier->tm_yday;
andrewboyson 26:0421132e6eaf 277
andrewboyson 26:0421132e6eaf 278 return days * 86400 +
andrewboyson 26:0421132e6eaf 279 (ptmLater->tm_hour - ptmEarlier->tm_hour) * 3600 +
andrewboyson 26:0421132e6eaf 280 (ptmLater->tm_min - ptmEarlier->tm_min ) * 60 +
andrewboyson 26:0421132e6eaf 281 (ptmLater->tm_sec - ptmEarlier->tm_sec );
andrewboyson 26:0421132e6eaf 282 }
andrewboyson 26:0421132e6eaf 283
andrewboyson 26:0421132e6eaf 284 void TimeTmUtcToLocal(struct tm* ptm)
andrewboyson 26:0421132e6eaf 285 {
andrewboyson 26:0421132e6eaf 286 //Establish DST
andrewboyson 26:0421132e6eaf 287 ptm->tm_isdst = isDst(ptm->tm_year, ptm->tm_mon, ptm->tm_mday, ptm->tm_wday, ptm->tm_hour);
andrewboyson 26:0421132e6eaf 288
andrewboyson 26:0421132e6eaf 289 //Adjust for the timezone
andrewboyson 26:0421132e6eaf 290 ptm->tm_hour += ptm->tm_isdst ? DST_OFFSET : STD_OFFSET;
andrewboyson 26:0421132e6eaf 291 normalise(&ptm->tm_hour, &ptm->tm_wday, &ptm->tm_mday, &ptm->tm_mon, &ptm->tm_yday, &ptm->tm_year);
andrewboyson 26:0421132e6eaf 292 }
andrewboyson 26:0421132e6eaf 293
andrewboyson 26:0421132e6eaf 294 void TimeAsciiDateTimeToTm(const char* pDate, const char* pTime, struct tm* ptm) // Convert compile time to system time
andrewboyson 26:0421132e6eaf 295 {
andrewboyson 26:0421132e6eaf 296 //__DATE__ The string constant contains eleven characters and looks like "Feb 12 1996". If the day of the month is less than 10, it is padded with a space on the left.
andrewboyson 26:0421132e6eaf 297 char month[5];
andrewboyson 26:0421132e6eaf 298 sscanf(pDate, "%s %d %d", month, &ptm->tm_mday, &ptm->tm_year); ptm->tm_year -= 1900;
andrewboyson 26:0421132e6eaf 299
andrewboyson 26:0421132e6eaf 300 // Find where month is in month_names. Deduce month value.
andrewboyson 26:0421132e6eaf 301 static const char month_names[] = "JanFebMarAprMayJunJulAugSepOctNovDec";
andrewboyson 26:0421132e6eaf 302 ptm->tm_mon = (strstr(month_names, month) - month_names) / 3;
andrewboyson 26:0421132e6eaf 303
andrewboyson 26:0421132e6eaf 304 //__TIME__ The string constant contains eight characters and looks like "23:59:01".
andrewboyson 26:0421132e6eaf 305 sscanf(pTime, "%2d %*c %2d %*c %2d", &ptm->tm_hour, &ptm->tm_min, &ptm->tm_sec);
andrewboyson 26:0421132e6eaf 306
andrewboyson 26:0421132e6eaf 307 //Fill the day of week and the day of year part of the tm structure
andrewboyson 26:0421132e6eaf 308 calculateDayOfYearAndWeek(ptm->tm_year, ptm->tm_mon, ptm->tm_mday, &ptm->tm_yday, &ptm->tm_wday);
andrewboyson 26:0421132e6eaf 309 }