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cloudbase.mooo.com Git - z180-stamp.git/blob - time/week_of_month.c
2 * (c)2012 Michael Duane Rice All rights reserved.
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29 /* $Id: week_of_month.c 2362 2013-04-26 22:22:46Z swfltek $ */
32 Return the week of month, where 'base' represents the starting day.
33 In the USA, the week is generally considered to start on Sunday (base = 0),
34 while in Europe it is generally considered to be Monday (base = 1).
36 Return value ranges from 0 to 5.
42 week_of_month(const struct tm
* timestruct
, uint8_t base
)
46 /* zero base the day of month */
47 n
= timestruct
->tm_mday
- 1;
49 /* find the first base day of the month (start of week 1) */
50 first
= 7 + n
- timestruct
->tm_wday
+ base
;
53 /* find days since the first week began */
56 /* if negative, we are in week 0 */