Files
ezic/src/ezic_loader.erl
2013-02-13 00:46:56 +04:00

120 lines
2.8 KiB
Erlang

-module(ezic_loader).
-include("include/ezic.hrl").
-export([load/0, load/1]).
-define(TZDIR, filename:join("priv", "tzdata")).
load() ->
case application:get_env(tzdata_dir) of
undefined ->
load(?TZDIR);
{ok, Dir} ->
load(Dir)
end.
%% returns all records, parsed from the tzdata files in directory Dir.
load(Dir) ->
{ok, Records} =
case filelib:is_dir(Dir) of
true -> {ok, parse_dir(Dir)};
false -> erlang:error({not_a_directory, Dir})
end,
Records.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% PRIVATE
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% returns a list of tzdata records for all files in folder
% note: assumes every file in the folder is a tzdata file
parse_dir(Dir) ->
{ok, Files} = file:list_dir(Dir),
lists:flatten([ parse_file(filename:join(Dir,File)) || File <- Files ]).
% returns a list of tzdata records from file
parse_file(File) ->
%% io:format("Parsing File: ~p~n", [File]),
{ok, FD} = file:open(File, [read]),
parse_lines(file:read_line(FD), FD, []).
parse_lines(eof, _, Records) ->
Records;
parse_lines({ok, Line}, File, Records) ->
StrLine= clean_line(Line),
NewRecords= case length(StrLine) > 0 of
true -> [parse_to_record(StrLine, File, Records) | Records];
false -> Records
end,
parse_lines(file:read_line(File), File, NewRecords).
% the Line has data, so we parse it, build a record, and return it
parse_to_record(Line, _, Records) ->
%% io:format(" Parsing Line: ~p~n", [Line]),
[Type | Data] = string:tokens(Line, " \t"),
{ok, PrevType, PrevName} = prev_rec_type(Records),
{ok, Record} = build_record(Type, Data, {PrevType, PrevName}),
Record.
% retrieves the previous record type, in case Zone continuations occur (multiline)
prev_rec_type([]) ->
{ok, null, null};
prev_rec_type([#zone{name=Name}|_]) ->
{ok, "Zone", Name};
prev_rec_type(List) when is_list(List) ->
{ok, void, void}.
clean_line(Line) ->
%% remove spaces, newlines, and tabs
Line1= string:strip(Line),
Line2= string:strip(Line1, both, $\n),
Line3= string:strip(Line2, both, $\t),
%% remove comments and returns
FinalLine=Line3,
CPos= string:chr(FinalLine, $#),
case CPos of
0 -> FinalLine;
_ -> string:sub_string(FinalLine, 1, CPos-1)
end.
build_record("Rule", Data,_) ->
ezic_rule:parse(Data);
build_record("Zone", Data,_) ->
ezic_zone:parse(Data);
build_record("Link", Data,_) ->
ezic_record:link(Data);
build_record("Leap", Data,_) ->
ezic_record:leap(Data);
build_record(GmtOff, Data, {"Zone", PrevName}) ->
ezic_zone:parse([PrevName,GmtOff|Data]);
build_record(Type, Data, PT) ->
erlang:error(badLine, {Type, Data, PT}).