Skip to content
Permalink
master
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

LPeg-Parsers/strftime.lua

Go to file
 
 
Cannot retrieve contributors at this time
366 lines (295 sloc) 10.9 KB
Raw Blame
Open in GitHub Desktop
-- ***************************************************************
--
-- Copyright 2018 by Sean Conner. All Rights Reserved.
--
-- This library is free software; you can redistribute it and/or modify it
-- under the terms of the GNU Lesser General Public License as published by
-- the Free Software Foundation; either version 3 of the License, or (at your
-- option) any later version.
--
-- This library is distributed in the hope that it will be useful, but
-- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
-- License for more details.
--
-- You should have received a copy of the GNU Lesser General Public License
-- along with this library; if not, see <http://www.gnu.org/licenses/>.
--
-- Comments, questions and criticisms can be sent to: sean@conman.org
--
-- ********************************************************************
-- luacheck: ignore 611
local os = require "os"
local lpeg = require "lpeg"
local tonumber = tonumber
local error = error
local string = string
local Cmt = lpeg.Cmt
local Cg = lpeg.Cg
local Ct = lpeg.Ct
local Cf = lpeg.Cf
local Cs = lpeg.Cs
local C = lpeg.C
local P = lpeg.P
local S = lpeg.S
local R = lpeg.R
-- ***********************************************************************
-- The following could be done easier and simpler with nl_langinfo(),
-- but that isn't portable (being a GNU extension). This *is* portable,
-- although we cannot get the formats used for "%c", "%x" or "%X".
-- ***********************************************************************
local short_months = {}
local long_months = {}
local short_days = {}
local long_days = {}
local am_pm = {}
do
local key
local now = { year = 2013 , month = 1 , day = 1 , hour = 0 }
for m = 1 , 12 do
now.month = m
key = os.date("%b", os.time(now))
short_months[key] = m
key = os.date("%B", os.time(now))
long_months[key] = m
end
for d = 1 , 7 do
now.day = d
key = os.date("%a", os.time(now))
short_days[key] = d
key = os.date("%A", os.time(now))
long_days[key] = d
end
now.hour = 0
key = os.date("%p", os.time(now))
am_pm[key] = 0
am_pm[key:lower()] = 0 -- GNU extension
now.hour = 12
key = os.date("%p", os.time(now))
am_pm[key] = 12
am_pm[key:lower()] = 12 -- GNU extension
end
-- ********************************************************************
local function chkrange(min,max)
return function(_,position,capture)
local val = tonumber(capture)
if val < min or val > max then
return false
else
return position,val
end
end
end
local utf8c = R"\128\191"
local utf8 = R"\192\207" * utf8c
+ R"\208\223" * utf8c * utf8c
+ R"\224\247" * utf8c * utf8c * utf8c
+ R"\248\251" * utf8c * utf8c * utf8c * utf8c
+ R"\252\253" * utf8c * utf8c * utf8c * utf8c * utf8c
local char = R("AZ","az") + utf8
local digit = R"09"
local dday = Cmt(digit * digit, chkrange(1, 31))
local d24hour = Cmt(digit * digit, chkrange(0, 23))
local d12hour = Cmt(digit * digit, chkrange(1, 12))
local ddyear = Cmt(digit * digit * digit,chkrange(1,366))
local dmonth = Cmt(digit * digit, chkrange(1, 12))
local dminute = Cmt(digit * digit, chkrange(0, 59))
local dsecond = Cmt(digit * digit, chkrange(0, 61))
local dweeknum = Cmt(digit * digit, chkrange(0, 53))
local dweek = Cmt(digit, chkrange(0, 6))
local d2year = (digit * digit) / function(c) return c + 1900 end
local d4year = (digit * digit * digit * digit) / tonumber
local number = (S"-+" * digit * digit * digit * digit)
local dweek1 = Cmt(digit, function(_,position,capture)
local v = tonumber(capture)
if v < 1 or v > 7 then
return false
else
if v == 7 then
v = 0
end
return position,v
end
end)
-- ********************************************************************
local oct = R"07"
local hex = R("09","AF","af")
local normal = C(P(1) - (P[[\]] + P"%"))
local escaped = P[[\n]] / "\n"
+ P[[\t]] / "\t"
+ P[[\v]] / "\v"
+ P[[\b]] / "\b"
+ P[[\r]] / "\r"
+ P[[\f]] / "\f"
+ P[[\a]] / "\a"
+ P[[\\]] / "\\"
+ P[[\?]] / "?"
+ P[[\']] / "'"
+ P[[\"]] / '"'
+ P[[\]] * C(oct * oct * oct) / function(c) return tonumber(c,8) end
+ P[[\x]] * C(hex * hex) / function(c) return tonumber(c,16) end
local text = Cs((escaped + normal)^1)
/ function(c) return P(c) end
-- -------------------------------------------------------------------
local directives = P"a" / function()
return Cg(char^1 / short_days,"wday")
end
+ P"A" / function()
return Cg(char^1 / long_days,"wday")
end
+ P"b" / function()
return Cg(char^1 / short_months,"month")
end
+ P"B" / function()
return Cg(char^1 / long_months,"month")
end
+ P"c" / function()
error("%c format specifier not supported")
end
+ P"d" / function()
return Cg(dday,"day")
end
+ P"H" / function()
return Cg(d24hour,"hour")
end
+ P"I" / function()
return Cg(d12hour,"hour")
end
+ P"j" / function()
return Cg(ddyear,"yday")
end
+ P"m" / function()
return Cg(dmonth,"month")
end
+ P"M" / function()
return Cg(dminute,"min")
end
+ P"p" / function()
return Cg(char^1 / am_pm,"pm")
end
+ P"S" / function()
return Cg(dsecond,"sec")
end
+ P"U" / function()
return Cg(dweeknum,"weeknums")
end
+ P"w" / function()
return Cg(dweek,"wday")
end
+ P"W" / function()
return Cg(dweeknum,"weeknumm")
end
+ P"x" / function()
error("%x format specifier not supported")
end
+ P"X" / function()
error("%X format specifier not supported")
end
+ P"y" / function()
return Cg(d2year,"year")
end
+ P"Y" / function()
return Cg(d4year,"year")
end
+ P"Z" / function()
return Cg(char^1,"zone")
end
+ P"%" / function()
return P"%"
end
-- -------------------------------------------------------------------
-- C99 extensions
-- -------------------------------------------------------------------
+ P"C" / function()
return Cg(d2year,"year")
end
+ P"D" / function()
return Cg(dmonth,"month") * P"/"
* Cg(dday,"day") * P"/"
* Cg(d2year,"year")
end
+ P"e" / function()
return P" "^-1
* Cg(Cmt(digit^1,chkrange(1,31)),"day")
end
+ P"F" / function()
return Cg(d4year,"year") * P"-"
* Cg(dmonth,"month") * P"-"
* Cg(dday,"day")
end
+ P"g" / function()
return Cg(d2year,"year")
end
+ P"G" / function()
return Cg(d4year,"year")
end
+ P"h" / function()
return Cg(char^1 / short_months,"month")
end
+ P"n" / function()
return P"\n"
end
+ P"r" / function()
return Cg(d12hour,"hour") * P":"
* Cg(dminute,"min") * P":"
* Cg(dsecond,"sec") * P" "
* Cg(char^1 / am_pm,"pm")
end
+ P"R" / function()
return Cg(d24hour,"hour") * P":"
* Cg(dminute,"min")
end
+ P"t" / function()
return P"\t"
end
+ P"T" / function()
return Cg(d24hour,"hour") * P":"
* Cg(dminute,"min") * P":"
* Cg(dsecond,"sec")
end
+ P"u" / function()
return Cg(dweek1,"wday")
end
+ P"V" / function()
return Cg(dweeknum,"weeknumm4")
end
+ P"z" / function()
return Cg(number,"zone")
end
+ P"E" / function()
error("%E format modifier not supported")
end
+ P"O" / function()
error("%O format modifier not supported")
end
-- -------------------------------------------------------------------
-- others
-- -------------------------------------------------------------------
+ P"k" / function()
return P" "^-1
* Cg(Cmt(digit^1,chkrange(1,23)),"hour")
end
+ P"l" / function()
return P" "^-1
* Cg(Cmt(digit^1,chkrange(1,12)),"hour")
end
+ P"P" / function()
return Cg(char^1 / am_pm,"pm")
end
+ P"s" / function()
return Cg(digit^1 / tonumber,"epoch")
end
+ P"+" / function()
error("%+ format specifier not supported")
end
-- -------------------------------------------------------------------
-- Catch all
-- -------------------------------------------------------------------
+ P(1) / function(c)
error(string.format("%%%s format specifier not supported",c))
end
local directive = P"%" * directives
return Cf((text + directive)^0,function(a,b) return a * b end)
/ function(c)
return Ct(c)
end