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authorJohn Denker <jsd@av8n.com>2012-06-01 18:58:45 -0700
committerJohn Denker <jsd@av8n.com>2012-06-01 18:58:45 -0700
commitb732a73bc773789894466b0e5320b2f1fe42c7e9 (patch)
tree385358983f064a1f10a5080b33a3ba13010886db /datetime_un.c
parent634d365a03cb0581a062cd3cf4db9ae69f1cde26 (diff)
original, as downloaded from http://www.qmail.org/netqmail-1.06.tar.gz
Diffstat (limited to 'datetime_un.c')
-rw-r--r--datetime_un.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/datetime_un.c b/datetime_un.c
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index 0000000..b5048f8
--- /dev/null
+++ b/datetime_un.c
@@ -0,0 +1,35 @@
+#include "datetime.h"
+
+/* roughly 100x faster than mktime() */
+datetime_sec datetime_untai(dt)
+struct datetime *dt;
+{
+ int year;
+ int day;
+ int mon;
+
+ year = dt->year + 1900;
+
+ mon = dt->mon;
+ if (mon >= 2) { mon -= 2; }
+ else { mon += 10; --year; }
+
+ day = (dt->mday - 1) * 10 + 5 + 306 * mon;
+ day /= 10;
+
+ if (day == 365) { year -= 3; day = 1460; }
+ else { day += 365 * (year % 4); }
+ year /= 4;
+
+ day += 1461 * (year % 25);
+ year /= 25;
+
+ if (day == 36524) { year -= 3; day = 146096; }
+ else { day += 36524 * (year % 4); }
+ year /= 4;
+
+ day += 146097 * (year - 5);
+ day += 11017;
+
+ return ((day * 24 + dt->hour) * 60 + dt->min) * 60 + dt->sec;
+}