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authorJannis Hoffmann <jannis@fehcom.de>2024-07-03 15:48:04 +0200
committerJannis Hoffmann <jannis@fehcom.de>2024-07-03 15:48:04 +0200
commit89b7b67a13ebb7965cc7f13ad0595e2194a2d34c (patch)
tree25efd77a90ae87236e6730d8ea3846bbe0fd126f /src/datetime_un.c
add sqmail-4.2.29asqmail-4.2
Diffstat (limited to 'src/datetime_un.c')
-rw-r--r--src/datetime_un.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/src/datetime_un.c b/src/datetime_un.c
new file mode 100644
index 0000000..e84806d
--- /dev/null
+++ b/src/datetime_un.c
@@ -0,0 +1,35 @@
+#include "datetime.h"
+
+/* roughly 100x faster than mktime() */
+
+datetime_sec datetime_untai(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;
+}