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Undo last change.

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This commit is contained in:
Roland McGrath
1993-08-10 17:57:31 +00:00
parent 8bab5c187a
commit 4cc1b78aef
1 changed files with 6 additions and 6 deletions
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12
lisp/calendar/cal-dst.el
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@@ -58,13 +58,13 @@ absolute date ABS-DATE is the equivalent moment to X."
(let* ((h (car x))
(xtail (cdr x))
(l (+ utc-diff (if (numberp xtail) xtail (car xtail))))
(u (+ (* 512 (% h 675)) (floor (/ l 128)))))
(u (+ (* 512 (mod h 675)) (floor l 128))))
;; Overflow is a terrible thing!
(cons (+ calendar-system-time-basis
;; floor((2^16 h +l) / (60*60*24))
(* 512 (% h 675)) (floor (/ u 675)))
(* 512 (mod h 675)) (floor u 675))
;; (2^16 h +l) % (60*60*24)
(+ (* (% u 675) 128) (floor (% l 128))))))
(+ (* (mod u 675) 128) (floor l 128)))))
(defun calendar-time-from-absolute (abs-date s)
"Time of absolute date ABS-DATE, S seconds after midnight.
@@ -74,13 +74,13 @@ Returns the pair (HIGH . LOW) where HIGH and LOW are the high and low
ignoring leap seconds, that is the equivalent moment to S seconds after
midnight UTC on absolute date ABS-DATE."
(let* ((a (- abs-date calendar-system-time-basis))
(u (+ (* 163 (% a 512)) (floor (/ s 128)))))
(u (+ (* 163 (mod a 512)) (floor s 128))))
;; Overflow is a terrible thing!
(cons
;; (60*60*24*a + s) / 2^16
(+ a (* 163 (floor (/ a 512))) (floor (/ u 512)))
(+ a (* 163 (floor a 512)) (floor u 512))
;; (60*60*24*a + s) % 2^16
(+ (* 128 (% u 512)) (% s 128)))))
(+ (* 128 (mod u 512)) (mod s 128)))))
(defun calendar-next-time-zone-transition (time)
"Return the time of the next time zone transition after TIME.