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diff --git a/src/simplec_hostsfile.erl b/src/simplec_hostsfile.erl
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+%%%-------------------------------------------------------------------
+%%% @author Guido <agx@bogon.m.sigxcpu.org>
+%%% @copyright (C) 2015, Guido G√ľnther
+%%% @doc
+%%%
+%%% @end
+%%% Created : 30 Aug 2015 by Guido <agx@bogon.m.sigxcpu.org>
+%%%-------------------------------------------------------------------
+-module(simplec_hostsfile).
+
+-behaviour(gen_server).
+
+-include("simplec.hrl").
+
+%% API
+-export([start_link/1,
+ write/1]).
+
+%% gen_server callbacks
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
+ terminate/2, code_change/3]).
+
+-define(SERVER, ?MODULE).
+
+-record(state, {config}).
+
+%%%===================================================================
+%%% API
+%%%===================================================================
+
+%%--------------------------------------------------------------------
+%% @doc
+%% Starts the server
+%%
+%% @spec start_link() -> {ok, Pid} | ignore | {error, Error}
+%% @end
+%%--------------------------------------------------------------------
+start_link(Config) ->
+ gen_server:start_link({local, ?SERVER}, ?MODULE, Config, []).
+
+
+%%--------------------------------------------------------------------
+%% @doc
+%% Writes out the hosts
+%% @end
+%%--------------------------------------------------------------------
+write(Hosts) ->
+ gen_server:cast(simplec_hostsfile, {hosts, Hosts}).
+
+
+%%%===================================================================
+%%% gen_server callbacks
+%%%===================================================================
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% Initializes the server
+%%
+%% @spec init(Args) -> {ok, State} |
+%% {ok, State, Timeout} |
+%% ignore |
+%% {stop, Reason}
+%% @end
+%%--------------------------------------------------------------------
+init(Config) ->
+ State = #state{config=Config},
+ % Make sure the file exists
+ write_hostsfile(State, {hosts, []}),
+ {ok, State}.
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% Handling call messages
+%%
+%% @spec handle_call(Request, From, State) ->
+%% {reply, Reply, State} |
+%% {reply, Reply, State, Timeout} |
+%% {noreply, State} |
+%% {noreply, State, Timeout} |
+%% {stop, Reason, Reply, State} |
+%% {stop, Reason, State}
+%% @end
+%%--------------------------------------------------------------------
+handle_call(_Request, _From, State) ->
+ Reply = ok,
+ {reply, Reply, State}.
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% Handling cast messages
+%%
+%% @spec handle_cast(Msg, State) -> {noreply, State} |
+%% {noreply, State, Timeout} |
+%% {stop, Reason, State}
+%% @end
+%%--------------------------------------------------------------------
+handle_cast({hosts, Hosts}, State) ->
+ write_hostsfile(State, {hosts, Hosts}),
+ {noreply, State}.
+
+
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% Handling all non call/cast messages
+%%
+%% @spec handle_info(Info, State) -> {noreply, State} |
+%% {noreply, State, Timeout} |
+%% {stop, Reason, State}
+%% @end
+%%--------------------------------------------------------------------
+handle_info(_Info, State) ->
+ {noreply, State}.
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% This function is called by a gen_server when it is about to
+%% terminate. It should be the opposite of Module:init/1 and do any
+%% necessary cleaning up. When it returns, the gen_server terminates
+%% with Reason. The return value is ignored.
+%%
+%% @spec terminate(Reason, State) -> void()
+%% @end
+%%--------------------------------------------------------------------
+terminate(_Reason, _State) ->
+ ok.
+
+%%--------------------------------------------------------------------
+%% @private
+%% @doc
+%% Convert process state when code is changed
+%%
+%% @spec code_change(OldVsn, State, Extra) -> {ok, NewState}
+%% @end
+%%--------------------------------------------------------------------
+code_change(_OldVsn, State, _Extra) ->
+ {ok, State}.
+
+%%%===================================================================
+%%% Internal functions
+%%%===================================================================
+
+
+write_line(Host, Addr) ->
+ write_line(Host, Addr, []).
+
+write_line(_Host, [], Aggr) ->
+ Aggr;
+write_line(Host, [H|T], Aggr) ->
+ write_line(Host, T, [io_lib:format("~s ~s~n",[H,Host])|Aggr]).
+
+
+write_hostsfile(#state{config=Config}, {hosts, Hosts}) ->
+ File = filename:join(Config#config.dir,
+ "libvirt-" ++ http_uri:encode(Config#config.url) ++ ".hosts"),
+ TmpFile = File ++ [".tmp"],
+ Data = [ write_line(Host, Addrs) || {Host, Addrs} <- Hosts ],
+ file:write_file(TmpFile, Data),
+ file:rename(TmpFile, File).