selfforum-cgi/shared/Time/German.pm

   1 package Time::German;
   2
   3 ################################################################################
   4 #                                                                              #
   5 # File:        shared/Time/German.pm                                           #
   6 #                                                                              #
   7 # Authors:     Andre Malo       <nd@o3media.de>, 2001-06-10                    #
   8 #                                                                              #
   9 # Description: determine time offset German Time <=> GMT (seconds)             #
  10 #                                                                              #
  11 ################################################################################
  12
  13 use strict;
  14 use vars qw(
  15   @EXPORT_OK
  16   %EXPORT_TAGS
  17   $VERSION
  18 );
  19
  20 ################################################################################
  21 #
  22 # Version check
  23 #
  24 $VERSION = do { my @r =(q$Revision$ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r };
  25
  26 ################################################################################
  27 #
  28 # Export
  29 #
  30 use base 'Exporter';
  31 @EXPORT_OK   = qw(localtime);
  32 %EXPORT_TAGS = (overwrite_internal_localtime => 'localtime'); # ;-)) Thanks to Calocybe
  33
  34 ################################################################################
  35 #
  36 # german summertime 1980-1995 (ydays)
  37 #
  38 my %summertime = (
  39   80 => [96, 271],
  40   81 => [87, 269],
  41   82 => [86, 268],
  42   83 => [85, 267],
  43   84 => [84, 273],
  44   85 => [89, 271],
  45   86 => [88, 270],
  46   87 => [87, 269],
  47   88 => [86, 268],
  48   89 => [84, 266],
  49   90 => [83, 272],
  50   91 => [89, 271],
  51   92 => [88, 270],
  52   93 => [86, 268],
  53   94 => [85, 267],
  54   95 => [84, 266]
  55 );
  56
  57 ### localtime () ###############################################################
  58 #
  59 # like 'localtime', but system independent
  60 #
  61 # Params: $time - time since epoch (GMT)
  62 #
  63 # Return: same as localtime, but german time ;-)
  64 #
  65 sub localtime (;$) {
  66   my $time = shift;
  67   $time = time unless defined $time;
  68
  69   my ($hour,$mday,$mon,$year,$wday,$yday) = (gmtime($time))[qw(2 3 4 5 6 7)];
  70   my $offset = 1;
  71
  72   # 1980 - 1995
  73   #
  74   if ($summertime{$year}) {
  75     $offset++ if (
  76       (
  77         $yday >  $summertime{$year} -> [0]  and
  78         $yday <  $summertime{$year} -> [1]
  79       ) or
  80       (
  81         $yday == $summertime{$year} -> [0]  and
  82         $hour >= 1
  83       ) or
  84       (
  85         $yday == $summertime{$year} -> [1]  and
  86         $hour <= 1
  87       )
  88     );
  89   }
  90
  91   # > 1995
  92   #
  93   elsif ($year > 95) {
  94     # determine last Sunday in March or October
  95     #
  96     my $limit = $mday + int((31-$mday)/7) * 7 - $wday if ($mon == 2 or $mon == 9);
  97
  98     $offset++ if (
  99       (
 100         $mon > 2          and
 101         $mon < 9
 102       ) or
 103       (
 104         $mon  == 2        and
 105         (
 106           $mday >  $limit  or
 107           $mday == $limit and
 108           $hour >= 1
 109         )
 110       ) or
 111       (
 112         $mon == 9         and
 113         (
 114           $mday <  $limit  or
 115           $mday == $limit and
 116           $hour <= 1
 117         )
 118       )
 119     );
 120   }
 121
 122   return gmtime($time + $offset * 3600);
 123 }
 124
 125 # keep 'require' happy
 126 1;
 127
 128 #
 129 #
 130 ### end of Time::German ########################################################