%%%----------------------------------------------------------------------
%%% File : ejabberd_loglevel.erl
%%% Author : Mickael Remond <mremond@process-one.net>
%%% Purpose : Loglevel switcher.
%%% Be careful: you should not have any ejabberd_logger module
%%% as ejabberd_loglevel switcher is compiling and loading
%%% dynamically a "virtual" ejabberd_logger module (Described
%%% in a string at the end of this module).
%%% Created : 29 Nov 2006 by Mickael Remond <mremond@process-one.net>
%%%
%%%
%%% ejabberd, Copyright (C) 2002-2008 Process-one
%%%
%%% This program is free software; you can redistribute it and/or
%%% modify it under the terms of the GNU General Public License as
%%% published by the Free Software Foundation; either version 2 of the
%%% License, or (at your option) any later version.
%%%
%%% This program 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
%%% General Public License for more details.
%%%
%%% You should have received a copy of the GNU General Public License
%%% along with this program; if not, write to the Free Software
%%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
%%% 02111-1307 USA
%%%
%%%----------------------------------------------------------------------
-module(ejabberd_loglevel).
-author('mickael.remond@process-one.net').
-export([set/1]).
-include("ejabberd.hrl").
-define(LOGMODULE, "error_logger").
%% Error levels:
%% 0 -> No log
%% 1 -> Critical
%% 2 -> Error
%% 3 -> Warning
%% 4 -> Info
%% 5 -> Debug
set(Loglevel) when is_integer(Loglevel) ->
Forms = compile_string(?LOGMODULE, ejabberd_logger_src(Loglevel)),
load_logger(Forms, ?LOGMODULE, Loglevel);
set(_) ->
exit("Loglevel must be an integer").
%% --------------------------------------------------------------
%% Compile a string into a module and returns the binary
compile_string(Mod, Str) ->
Fname = Mod ++ ".erl",
{ok, Fd} = open_ram_file(Fname),
file:write(Fd, Str),
file:position(Fd, 0),
case epp_dodger:parse(Fd) of
{ok, Tree} ->
Forms = revert_tree(Tree),
close_ram_file(Fd),
Forms;
Error ->
close_ram_file(Fd),
Error
end.
open_ram_file(Fname) ->
ram_file_io_server:start(self(), Fname, [read,write]).
close_ram_file(Fd) ->
file:close(Fd).
revert_tree(Tree) ->
[erl_syntax:revert(T) || T <- Tree].
load_logger(Forms, Mod, Loglevel) ->
Fname = Mod ++ ".erl",
case compile:forms(Forms, [binary, {d,'LOGLEVEL',Loglevel}]) of
{ok, M, Bin} ->
code:load_binary(M, Fname, Bin);
Error ->
?CRITICAL_MSG("Error ~p~n", [Error])
end.
%% --------------------------------------------------------------
%% Code of the ejabberd logger, dynamically compiled and loaded
%% This allows to dynamically change log level while keeping a
%% very efficient code.
ejabberd_logger_src(Loglevel) ->
L = integer_to_list(Loglevel),
"-module(ejabberd_logger).
-author('mickael.remond@process-one.net').
-export([debug_msg/4,
info_msg/4,
warning_msg/4,
error_msg/4,
critical_msg/4]).
%% Helper functions
debug_msg(Module, Line, Format, Args) when " ++ L ++ " >= 5 ->
notify(info_msg,
\"D(~p:~p:~p) : \"++Format++\"~n\",
[self(), Module, Line]++Args);
debug_msg(_,_,_,_) -> ok.
info_msg(Module, Line, Format, Args) when " ++ L ++ " >= 4 ->
notify(info_msg,
\"I(~p:~p:~p) : \"++Format++\"~n\",
[self(), Module, Line]++Args);
info_msg(_,_,_,_) -> ok.
warning_msg(Module, Line, Format, Args) when " ++ L ++ " >= 3 ->
notify(error,
\"W(~p:~p:~p) : \"++Format++\"~n\",
[self(), Module, Line]++Args);
warning_msg(_,_,_,_) -> ok.
error_msg(Module, Line, Format, Args) when " ++ L ++ " >= 2 ->
notify(error,
\"E(~p:~p:~p) : \"++Format++\"~n\",
[self(), Module, Line]++Args);
error_msg(_,_,_,_) -> ok.
critical_msg(Module, Line, Format, Args) when " ++ L ++ " >= 1 ->
notify(error,
\"C(~p:~p:~p) : \"++Format++\"~n\",
[self(), Module, Line]++Args);
critical_msg(_,_,_,_) -> ok.
%% Distribute the message to the Erlang error logger
notify(Type, Format, Args) ->
LoggerMsg = {Type, group_leader(), {self(), Format, Args}},
gen_event:notify(error_logger, LoggerMsg).
".
