lib/iconv/src/iconv.erl

   1 -module(iconv).
   2 %%%----------------------------------------------------------------------
   3 %%% File    : iconv.erl
   4 %%% Author  : Torbjorn Tornkvist <tobbe@bluetail.com>
   5 %%% Purpose : iconv support
   6 %%% Created : 23 Mar 2004 by <tobbe@bluetail.com>
   7 %%%
   8 %%% $Id$
   9 %%%----------------------------------------------------------------------
  10 -behaviour(gen_server).
  11 -export([start/0, start_link/0, open/2, conv/2, close/1]).
  12
  13 %% gen_server callbacks
  14 -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
  15          terminate/2, code_change/3]).
  16
  17 -record(state, {port}).
  18
  19 %%% op codes
  20 -define(IV_OPEN,    $o).
  21 -define(IV_CONV,    $v).
  22 -define(IV_CLOSE,   $c).
  23
  24
  25 -define(DRV_NAME, "iconv_drv").
  26 -define(SERVER, ?MODULE).
  27
  28 %%%----------------------------------------------------------------------
  29 %%% API
  30 %%%----------------------------------------------------------------------
  31 start() ->
  32     gen_server:start({local, ?SERVER}, ?MODULE, [], []).
  33
  34 start_link() ->
  35     gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
  36
  37 %%open(To, From) -> {ok, ballen};
  38 open(To, From) ->
  39     gen_server:call(?SERVER, {open, l2b(To), l2b(From)}, infinity).
  40
  41 %%conv(Cd, String) -> {ok, l2b(String)};
  42 conv(Cd, String) when binary(Cd) ->
  43     gen_server:call(?SERVER, {conv, Cd, l2b(String)}, infinity).
  44
  45 %%close(Cd) -> ok;
  46 close(Cd) when binary(Cd) ->
  47     gen_server:call(?SERVER, {close, Cd}, infinity).
  48
  49 %%%----------------------------------------------------------------------
  50 %%% Callback functions from gen_server
  51 %%%----------------------------------------------------------------------
  52
  53 %%----------------------------------------------------------------------
  54 %% Func: init/1
  55 %% Returns: {ok, State}          |
  56 %%          {ok, State, Timeout} |
  57 %%          ignore               |
  58 %%          {stop, Reason}
  59 %%----------------------------------------------------------------------
  60 init([]) ->
  61     erl_ddll:start(),
  62     Path = code:priv_dir(iconv),
  63     erl_ddll:load_driver(Path, ?DRV_NAME),
  64     Port = open_port({spawn, ?DRV_NAME}, [binary]),
  65     {ok, #state{port = Port}}.
  66
  67 %%----------------------------------------------------------------------
  68 %% Func: handle_call/3
  69 %% Returns: {reply, Reply, State}          |
  70 %%          {reply, Reply, State, Timeout} |
  71 %%          {noreply, State}               |
  72 %%          {noreply, State, Timeout}      |
  73 %%          {stop, Reason, Reply, State}   | (terminate/2 is called)
  74 %%          {stop, Reason, State}            (terminate/2 is called)
  75 %%----------------------------------------------------------------------
  76 handle_call({open, To, From}, _, S) ->
  77     ToLen   = size(To),
  78     FromLen = size(From),
  79     Msg = <<?IV_OPEN,ToLen:16,To/binary,FromLen:16,From/binary>>,
  80     Reply = call_drv(S#state.port, Msg),
  81     {reply, Reply, S};
  82 %%
  83 handle_call({conv, Cd, Buf}, _, S) ->
  84     CdLen  = size(Cd),
  85     BufLen = size(Buf),
  86     Msg = <<?IV_CONV,CdLen:16,Cd/binary,BufLen:16,Buf/binary>>,
  87     Reply = call_drv(S#state.port, Msg),
  88     {reply, Reply, S};
  89 %%
  90 handle_call({close, Cd}, _, S) ->
  91     CdLen  = size(Cd),
  92     Msg = <<?IV_CLOSE,CdLen:16,Cd/binary>>,
  93     Reply = call_drv(S#state.port, Msg),
  94     {reply, Reply, S}.
  95
  96 call_drv(Port, Msg) ->
  97     erlang:port_command(Port, [Msg]),
  98     recv(Port).
  99
 100 recv(Port) ->
 101     receive
 102         {Port, ok} ->
 103             ok;
 104         {Port, value, Bin} ->
 105             {ok,Bin};
 106         {Port, error, ErrAtom} ->
 107             {error, ErrAtom}
 108     end.
 109
 110
 111
 112 %%----------------------------------------------------------------------
 113 %% Func: handle_cast/2
 114 %% Returns: {noreply, State}          |
 115 %%          {noreply, State, Timeout} |
 116 %%          {stop, Reason, State}            (terminate/2 is called)
 117 %%----------------------------------------------------------------------
 118 handle_cast(_Msg, State) ->
 119     {noreply, State}.
 120
 121 %%----------------------------------------------------------------------
 122 %% Func: handle_info/2
 123 %% Returns: {noreply, State}          |
 124 %%          {noreply, State, Timeout} |
 125 %%          {stop, Reason, State}            (terminate/2 is called)
 126 %%----------------------------------------------------------------------
 127 handle_info(_Info, State) ->
 128     {noreply, State}.
 129
 130 %%----------------------------------------------------------------------
 131 %% Func: terminate/2
 132 %% Purpose: Shutdown the server
 133 %% Returns: any (ignored by gen_server)
 134 %%----------------------------------------------------------------------
 135 terminate(_Reason, _State) ->
 136     ok.
 137
 138
 139 code_change(_, _, _) ->
 140     ok.
 141
 142 %%%----------------------------------------------------------------------
 143 %%% Internal functions
 144 %%%----------------------------------------------------------------------
 145
 146 load_path(File) ->
 147     case lists:zf(fun(Ebin) ->
 148                           Priv = Ebin ++ "/../priv/",
 149                           case file:read_file_info(Priv ++ File) of
 150                               {ok, _} -> {true, Priv};
 151                               _ -> false
 152                           end
 153                   end, code:get_path()) of
 154         [Dir|_] ->
 155             {ok, Dir};
 156         [] ->
 157             error_logger:format("Error: ~s not found in code path\n", [File]),
 158             {error, enoent}
 159     end.
 160
 161 l2b(L) when list(L)   -> list_to_binary(L);
 162 l2b(B) when binary(B) -> B.