X-Git-Url: http://git.kpe.io/?p=kmrcl.git;a=blobdiff_plain;f=datetime.lisp;h=b865f48a3ece1d541d2ecea8e2d3119ec5e5939e;hp=f8aca20d74cd6b235c8fcec8b73d151dc783386b;hb=HEAD;hpb=78b62107690123d8d7a1a400e4a1d744408a05b1

diff --git a/datetime.lisp b/datetime.lisp
index f8aca20..b865f48 100644
--- a/datetime.lisp
+++ b/datetime.lisp
@@ -7,8 +7,6 @@
 ;;;; Programmer:    Kevin M. Rosenberg
 ;;;; Date Started:  Apr 2000
 ;;;;
-;;;; $Id$
-;;;;
 ;;;; This file, part of KMRCL, is Copyright (c) 2002 by Kevin M. Rosenberg
 ;;;;
 ;;;; KMRCL users are granted the rights to distribute and use this software
@@ -26,27 +24,67 @@
     (decode-universal-time
      (encode-universal-time s m hour day month year))
     (values (elt '("Monday" "Tuesday" "Wednesday" "Thursday"
-		   "Friday" "Saturday" "Sunday")
-		 wkday)
-	    (elt '("January" "February" "March" "April" "May" "June"
-		   "July" "August" "September" "October" "November"
-		   "December")
-		 (1- mn))
-	    (format nil "~A" dy) (format nil "~A" yr)
-	    (format nil "~2,'0D:~2,'0D:~2,'0D" hr min sec))))
-
-
-(defun date-string (ut)
+                   "Friday" "Saturday" "Sunday")
+                 wkday)
+            (elt '("January" "February" "March" "April" "May" "June"
+                   "July" "August" "September" "October" "November"
+                   "December")
+                 (1- mn))
+            (format nil "~A" dy)
+            (format nil "~A" yr)
+            (format nil "~2,'0D:~2,'0D:~2,'0D" hr min sec))))
+
+(defun pretty-date-ut (&optional (tm (get-universal-time)))
+  (multiple-value-bind (sec min hr dy mn yr) (decode-universal-time tm)
+    (pretty-date yr mn dy hr min sec)))
+
+(defun date-string (&optional (ut (get-universal-time)))
   (if (typep ut 'integer)
       (multiple-value-bind (sec min hr day mon year dow daylight-p zone)
-	  (decode-universal-time ut)
-	(declare (ignore daylight-p zone))
-	(format nil "~[Mon~;Tue~;Wed~;Thu~;Fri~;Sat~;Sun~], ~d ~[Jan~;Feb~;Mar~;Apr~;May~;Jun~;Jul~;Aug~;Sep~;Oct~;Nov~;Dec~] ~d ~2,'0d:~2,'0d:~2,'0d" 
-		dow
-		day
-		(1- mon)
-		year
-		hr min sec))))
+          (decode-universal-time ut)
+        (declare (ignore daylight-p zone))
+        (format nil "~[Mon~;Tue~;Wed~;Thu~;Fri~;Sat~;Sun~] ~d ~[Jan~;Feb~;Mar~;Apr~;May~;Jun~;Jul~;Aug~;Sep~;Oct~;Nov~;Dec~] ~d ~2,'0d:~2,'0d:~2,'0d"
+                dow
+                day
+                (1- mon)
+                year
+                hr min sec))))
+
+(eval-when (:compile-toplevel :load-toplevel :execute)
+  (defconstant +minute-seconds+ 60)
+  (defconstant +hour-seconds+ (* 60 +minute-seconds+))
+  (defconstant +day-seconds+ (* 24 +hour-seconds+))
+  (defconstant +week-seconds+ (* +day-seconds+ 7))
+  (defconstant +month-seconds+ (* +day-seconds+ (/ 365.25 12)))
+  (defconstant +year-seconds+ (* +day-seconds+ 365.25)))
+
+(defun seconds-to-condensed-time-string (sec &key (dp-digits 0))
+  "Prints a quantity of seconds as a condensed string. DP-DIGITS controls
+how many digits after decimal point."
+  (multiple-value-bind (year yrem) (floor (coerce sec 'double-float) +year-seconds+)
+    (multiple-value-bind (month mrem) (floor yrem +month-seconds+)
+      (multiple-value-bind (week wrem) (floor mrem +week-seconds+)
+        (multiple-value-bind (day drem) (floor wrem +day-seconds+)
+          (multiple-value-bind (hour hrem) (floor drem +hour-seconds+)
+            (multiple-value-bind (minute minrem) (floor hrem +minute-seconds+)
+              (let ((secstr (if (zerop dp-digits)
+                                (format nil "~Ds" (round minrem))
+                                (format nil (format nil "~~,~DFs" dp-digits) minrem))))
+                (cond
+                  ((plusp year)
+                   (format nil "~Dy~DM~Dw~Dd~Dh~Dm~A" year month week day hour minute secstr))
+                  ((plusp month)
+                   (format nil "~DM~Dw~Dd~Dh~Dm~A" month week day hour minute secstr))
+                  ((plusp week)
+                   (format nil "~Dw~Dd~Dh~Dm~A" week day hour minute secstr))
+                  ((plusp day)
+                   (format nil "~Dd~Dh~Dm~A" day hour minute secstr))
+                  ((plusp hour)
+                   (format nil "~Dh~Dm~A" hour minute secstr))
+                  ((plusp minute)
+                   (format nil "~Dm~A" minute secstr))
+                  (t
+                   secstr))))))))))
 
 (defun print-seconds (secs)
   (print-float-units secs "sec"))
@@ -74,6 +112,9 @@
 (defun posix-time-to-utime (time)
   (+ time +posix-epoch+))
 
+(defun utime-to-posix-time (utime)
+  (- utime +posix-epoch+))
+
 ;; Monthnames taken from net-telent-date to support lml2
 
 (defvar *monthnames*
@@ -92,6 +133,7 @@
 
 (defun monthname (stream arg colon-p at-p &optional width (mincol 0) (colinc 1) (minpad 0) (padchar #\Space))
   "Print the name of the month (1=January) corresponding to ARG on STREAM.  This is intended for embedding in a FORMAT directive: WIDTH governs the number of characters of text printed, MINCOL, COLINC, MINPAD, PADCHAR work as for ~A"
+  (declare (ignore colon-p))
   (let ((monthstring (cdr (assoc arg *monthnames*))))
     (if (not monthstring) (return-from monthname nil))
     (let ((truncate (if width (min width (length monthstring)) nil)))
@@ -100,7 +142,21 @@
               mincol colinc minpad padchar
               (subseq monthstring 0 truncate)))))
 
-;;;; Daylight Saving Time calculations 
+(defconstant* +zellers-adj+ #(0 3 2 5 0 3 5 1 4 6 2 4))
+
+(defun day-of-week (year month day)
+  "Day of week calculation using Zeller's Congruence.
+Input: The year y, month m (1 <= m <= 12) and day d (1 <= d <= 31).
+Output: n - the day of the week (Sunday = 0, Saturday = 6)."
+
+  (when (< month 3)
+    (decf year))
+  (mod
+   (+ year (floor year 4) (- (floor year 100)) (floor year 400)
+      (aref +zellers-adj+ (1- month)) day)
+   7))
+
+;;;; Daylight Saving Time calculations
 
 ;; Daylight Saving Time begins for most of the United States at 2
 ;; a.m. on the first Sunday of April. Time reverts to standard time at