libs/http/luasrc/http/protocol/date.lua

   1 --[[
   2
   3 HTTP protocol implementation for LuCI - date handling
   4 (c) 2008 Freifunk Leipzig / Jo-Philipp Wich <xm@leipzig.freifunk.net>
   5
   6 Licensed under the Apache License, Version 2.0 (the "License");
   7 you may not use this file except in compliance with the License.
   8 You may obtain a copy of the License at
   9
  10         http://www.apache.org/licenses/LICENSE-2.0
  11
  12 $Id$
  13
  14 ]]--
  15
  16 module("luci.http.protocol.date", package.seeall)
  17
  18 MONTHS = {
  19         "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug",
  20         "Sep", "Oct", "Nov", "Dec"
  21 }
  22
  23 -- This list is stolen from Perl's Time::Timezone
  24 TZ = {
  25         -- DST zones
  26         ["brst"]  =   -2*3600;   -- Brazil Summer Time (East Daylight)
  27         ["adt"]   =   -3*3600;   -- Atlantic Daylight
  28         ["edt"]   =   -4*3600;   -- Eastern Daylight
  29         ["cdt"]   =   -5*3600;   -- Central Daylight
  30         ["mdt"]   =   -6*3600;   -- Mountain Daylight
  31         ["pdt"]   =   -7*3600;   -- Pacific Daylight
  32         ["ydt"]   =   -8*3600;   -- Yukon Daylight
  33         ["hdt"]   =   -9*3600;   -- Hawaii Daylight
  34         ["bst"]   =    1*3600;   -- British Summer
  35         ["mest"]  =    2*3600;   -- Middle European Summer
  36         ["sst"]   =    2*3600;   -- Swedish Summer
  37         ["fst"]   =    2*3600;   -- French Summer
  38         ["eest"]  =    3*3600;   -- Eastern European Summer
  39         ["cest"]  =    2*3600;   -- Central European Daylight
  40         ["wadt"]  =    8*3600;   -- West Australian Daylight
  41         ["kdt"]   =   10*3600;   -- Korean Daylight
  42         ["eadt"]  =   11*3600;   -- Eastern Australian Daylight
  43         ["nzdt"]  =   13*3600;   -- New Zealand Daylight
  44
  45         -- zones
  46         ["gmt"]   =   0;                 -- Greenwich Mean
  47         ["ut"]    =   0;                 -- Universal (Coordinated)
  48         ["utc"]   =   0;
  49         ["wet"]   =   0;                 -- Western European
  50         ["wat"]   =  -1*3600;    -- West Africa
  51         ["azost"] =  -1*3600;    -- Azores Standard Time
  52         ["cvt"]   =  -1*3600;    -- Cape Verde Time
  53         ["at"]    =  -2*3600;    -- Azores
  54         ["fnt"]   =  -2*3600;    -- Brazil Time (Extreme East - Fernando Noronha)
  55         ["ndt"]   =  -2*3600+1800;-- Newfoundland Daylight
  56         ["art"]   =  -3*3600;    -- Argentina Time
  57         ["nft"]   =  -3*3600+1800;-- Newfoundland
  58         ["mnt"]   =  -4*3600;    -- Brazil Time (West Standard - Manaus)
  59         ["ewt"]   =  -4*3600;    -- U.S. Eastern War Time
  60         ["ast"]   =  -4*3600;    -- Atlantic Standard
  61         ["bot"]   =  -4*3600;    -- Bolivia Time
  62         ["vet"]   =  -4*3600;    -- Venezuela Time
  63         ["est"]   =  -5*3600;    -- Eastern Standard
  64         ["cot"]   =  -5*3600;    -- Colombia Time
  65         ["act"]   =  -5*3600;    -- Brazil Time (Extreme West - Acre)
  66         ["pet"]   =  -5*3600;    -- Peru Time
  67         ["cst"]   =  -6*3600;    -- Central Standard
  68         ["cest"]  =   2*3600;    -- Central European Summer
  69         ["mst"]   =  -7*3600;    -- Mountain Standard
  70         ["pst"]   =  -8*3600;    -- Pacific Standard
  71         ["yst"]   =  -9*3600;    -- Yukon Standard
  72         ["hst"]   = -10*3600;    -- Hawaii Standard
  73         ["cat"]   = -10*3600;    -- Central Alaska
  74         ["ahst"]  = -10*3600;    -- Alaska-Hawaii Standard
  75         ["taht"]  = -10*3600;    -- Tahiti Time
  76         ["nt"]    = -11*3600;    -- Nome
  77         ["idlw"]  = -12*3600;    -- International Date Line West
  78         ["cet"]   =   1*3600;    -- Central European
  79         ["mez"]   =   1*3600;    -- Central European (German)
  80         ["met"]   =   1*3600;    -- Middle European
  81         ["mewt"]  =   1*3600;    -- Middle European Winter
  82         ["swt"]   =   1*3600;    -- Swedish Winter
  83         ["set"]   =   1*3600;    -- Seychelles
  84         ["fwt"]   =   1*3600;    -- French Winter
  85         ["west"]  =   1*3600;    -- Western Europe Summer Time
  86         ["eet"]   =   2*3600;    -- Eastern Europe; USSR Zone 1
  87         ["ukr"]   =   2*3600;    -- Ukraine
  88         ["sast"]  =   2*3600;    -- South Africa Standard Time
  89         ["bt"]    =   3*3600;    -- Baghdad; USSR Zone 2
  90         ["eat"]   =   3*3600;    -- East Africa Time
  91         ["irst"]  =   3*3600+1800;-- Iran Standard Time
  92         ["zp4"]   =   4*3600;    -- USSR Zone 3
  93         ["msd"]   =   4*3600;    -- Moscow Daylight Time
  94         ["sct"]   =   4*3600;    -- Seychelles Time
  95         ["zp5"]   =   5*3600;    -- USSR Zone 4
  96         ["azst"]  =   5*3600;    -- Azerbaijan Summer Time
  97         ["mvt"]   =   5*3600;    -- Maldives Time
  98         ["uzt"]   =   5*3600;    -- Uzbekistan Time
  99         ["ist"]   =   5*3600+1800;-- Indian Standard
 100         ["zp6"]   =   6*3600;    -- USSR Zone 5
 101         ["lkt"]   =   6*3600;    -- Sri Lanka Time
 102         ["pkst"]  =   6*3600;    -- Pakistan Summer Time
 103         ["yekst"] =   6*3600;    -- Yekaterinburg Summer Time
 104         ["wast"]  =   7*3600;    -- West Australian Standard
 105         ["ict"]   =   7*3600;    -- Indochina Time
 106         ["wit"]   =   7*3600;    -- Western Indonesia Time
 107         ["cct"]   =   8*3600;    -- China Coast; USSR Zone 7
 108         ["wst"]   =   8*3600;    -- West Australian Standard
 109         ["hkt"]   =   8*3600;    -- Hong Kong
 110         ["bnt"]   =   8*3600;    -- Brunei Darussalam Time
 111         ["cit"]   =   8*3600;    -- Central Indonesia Time
 112         ["myt"]   =   8*3600;    -- Malaysia Time
 113         ["pht"]   =   8*3600;    -- Philippines Time
 114         ["sgt"]   =   8*3600;    -- Singapore Time
 115         ["jst"]   =   9*3600;    -- Japan Standard; USSR Zone 8
 116         ["kst"]   =   9*3600;    -- Korean Standard
 117         ["east"]  =  10*3600;    -- Eastern Australian Standard
 118         ["gst"]   =  10*3600;    -- Guam Standard; USSR Zone 9
 119         ["nct"]   =  11*3600;    -- New Caledonia Time
 120         ["nzt"]   =  12*3600;    -- New Zealand
 121         ["nzst"]  =  12*3600;    -- New Zealand Standard
 122         ["fjt"]   =  12*3600;    -- Fiji Time
 123         ["idle"]  =  12*3600;    -- International Date Line East
 124 }
 125
 126
 127 -- Find corresponding timezone offset
 128 function tz_offset(tz)
 129
 130         if type(tz) == "string" then
 131
 132                 -- check for a numeric identifier
 133                 local s, v = tz:match("([%+%-])([0-9]+)")
 134                 if s == '+' then s = 1 else s = -1 end
 135                 if v then v = tonumber(v) end
 136
 137                 if s and v then
 138                         return s * 60 * ( math.floor( v / 100 ) * 60 + ( v % 100 ) )
 139
 140                 -- lookup symbolic tz
 141                 elseif TZ[tz:lower()] then
 142                         return TZ[tz:lower()]
 143                 end
 144
 145         end
 146
 147         -- bad luck
 148         return 0
 149 end
 150
 151 -- Convert a HTTP date to unixtime
 152 function to_unix(date)
 153
 154         print("D: "..date)
 155
 156         local wd, day, mon, yr, hr, min, sec, tz = date:match(
 157                 "([A-Z][a-z][a-z]), ([0-9]+) " ..
 158                 "([A-Z][a-z][a-z]) ([0-9]+) " ..
 159                 "([0-9]+):([0-9]+):([0-9]+) " ..
 160                 "([A-Z0-9%+%-]+)"
 161         )
 162
 163         print(day .. " | " .. mon .. " | " .. yr .. " | " .. tz)
 164
 165         if day and mon and yr and hr and min and sec then
 166
 167                 -- find month
 168                 local month = 1
 169                 for i = 1, 12 do
 170                         if MONTHS[i] == mon then
 171                                 month = i
 172                                 break
 173                         end
 174                 end
 175
 176                 -- convert to epoch time
 177                 return tz_offset(tz) + os.time( {
 178                         year  = yr,
 179                         month = month,
 180                         day   = day,
 181                         hour  = hr,
 182                         min   = min,
 183                         sec   = sec
 184                 } )
 185         end
 186
 187         return 0
 188 end
 189
 190 -- Convert a unixtime to HTTP date
 191 function to_http(time)
 192         return os.date( "%a, %d %b %Y %H:%M:%S GMT", time )
 193 end
 194
 195 -- Compare to dates
 196 function compare(d1, d2)
 197
 198         if d1:match("[^0-9]") then d1 = to_unix(d1) end
 199         if d2:match("[^0-9]") then d2 = to_unix(d2) end
 200
 201         if d1 == d2 then
 202                 return 0
 203         elseif d1 < d2 then
 204                 return -1
 205         else
 206                 return 1
 207         end
 208 end