%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2005-2011. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
%%
%%----------------------------------------------------------------------
%% Purpose : Handle ASN.1 BER encoding of Megaco/H.248
%%----------------------------------------------------------------------
-module(megaco_binary_encoder_lib).
%% API
-export([
version_of/4,
decode_message/5, decode_message_dynamic/4,
decode_mini_message/4, decode_mini_message_dynamic/4,
encode_message/5,
encode_transaction/5,
encode_action_requests/5,
encode_action_request/5,
encode_action_reply/5
]).
-include_lib("megaco/src/engine/megaco_message_internal.hrl").
%%----------------------------------------------------------------------
%% Detect (check) which version a message is
%% Return {ok, Version} | {error, Reason}
%%----------------------------------------------------------------------
version_of(_EC, Binary, dynamic, [AsnModV1|_AsnMods])
when is_binary(Binary) andalso is_atom(AsnModV1) ->
case (catch AsnModV1:decode_message_version(Binary)) of
{ok, PartialMsg} ->
V = (PartialMsg#'MegacoMessage'.mess)#'Message'.version,
{ok, V};
Error ->
Error
end;
version_of(_EC, Binary, 1, AsnMods)
when is_binary(Binary) andalso is_list(AsnMods) ->
version_of(AsnMods, Binary, []);
version_of(_EC, Binary, 2, [AsnModV1, AsnModV2, AsnModV3])
when is_binary(Binary) ->
version_of([AsnModV2, AsnModV1, AsnModV3], Binary, []);
version_of(_EC, Binary, 3, [AsnModV1, AsnModV2, AsnModV3])
when is_binary(Binary) ->
version_of([AsnModV3, AsnModV1, AsnModV2], Binary, []).
version_of([], _Binary, Err) ->
{error, {decode_failed, lists:reverse(Err)}};
version_of([AsnMod|AsnMods], Binary, Errs) when is_atom(AsnMod) ->
case (catch asn1rt:decode(AsnMod, 'MegacoMessage', Binary)) of
{ok, M} ->
V = (M#'MegacoMessage'.mess)#'Message'.version,
{ok, V};
Err ->
version_of(AsnMods, Binary, [Err|Errs])
end.
%%----------------------------------------------------------------------
%% Convert a 'MegacoMessage' record into a binary
%% Return {ok, Binary} | {error, Reason}
%%----------------------------------------------------------------------
encode_message([native], MegaMsg, AsnMod, _TransMod, binary)
when is_record(MegaMsg, 'MegacoMessage') ->
asn1rt:encode(AsnMod, 'MegacoMessage', MegaMsg);
encode_message(EC, MegaMsg, AsnMod, TransMod, binary)
when is_list(EC) andalso is_record(MegaMsg, 'MegacoMessage') ->
case (catch TransMod:tr_message(MegaMsg, encode, EC)) of
{'EXIT', Reason} ->
{error, Reason};
MegaMsg2 ->
asn1rt:encode(AsnMod, 'MegacoMessage', MegaMsg2)
end;
encode_message(EC, MegaMsg, AsnMod, TransMod, io_list) ->
case encode_message(EC, MegaMsg, AsnMod, TransMod, binary) of
{ok, Bin} when is_binary(Bin) ->
{ok, Bin};
{ok, DeepIoList} ->
Bin = erlang:list_to_binary(DeepIoList),
{ok, Bin};
{error, Reason} ->
{error, Reason}
end;
encode_message(EC, MegaMsg, _AsnMod, _TransMod, _Type)
when is_record(MegaMsg, 'MegacoMessage') ->
{error, {bad_encoding_config, EC}};
encode_message(_EC, MegaMsg, _AsnMod, _TransMod, _Type) ->
{error, {no_megaco_message, MegaMsg}}.
%%----------------------------------------------------------------------
%% Convert a transaction (or transactions in the case of ack) record(s)
%% into a binary
%% Return {ok, Binary} | {error, Reason}
%%----------------------------------------------------------------------
%% Should handle encoding of all types of transactions:
%% TransactionAck, TransactionPending, TransactionRequest
%% and TransactionReply
encode_transaction(EC, {Tag, _} = Trans, AsnMod, TransMod, Type)
when (Tag == transactionResponseAck) ->
do_encode_transaction(EC, Trans, AsnMod, TransMod, Type);
encode_transaction(EC, {Tag, _} = Trans, AsnMod, TransMod, Type)
when (Tag == transactionPending) ->
do_encode_transaction(EC, Trans, AsnMod, TransMod, Type);
encode_transaction(EC, {Tag, _} = Trans, AsnMod, TransMod, Type)
when (Tag == transactionRequest) ->
do_encode_transaction(EC, Trans, AsnMod, TransMod, Type);
%% TransactionReply has been changed as of v3 so we cannot use
%% the record definition in this common module.
encode_transaction(EC, {Tag, _} = Trans, AsnMod, TransMod, Type)
when (Tag == transactionReply) ->
do_encode_transaction(EC, Trans, AsnMod, TransMod, Type);
encode_transaction(_EC, T, _AsnMod, _TransMod, _Type) ->
{error, {no_megaco_transaction, T}}.
-spec do_encode_transaction(EC :: list(),
Trans :: tuple(),
AnsMod :: atom(),
TransMod :: atom(),
Type :: atom()) ->
{'ok', binary()} | {'error', any()}.
do_encode_transaction([native], _Trans, _AsnMod, _TransMod, binary) ->
%% asn1rt:encode(AsnMod, element(1, T), T);
{error, not_implemented};
do_encode_transaction(EC, _Trans, _AsnMod, _TransMod, binary)
when is_list(EC) ->
%% T2 = TransMod:tr_transaction(Trans, encode, EC),
%% asn1rt:encode(AsnMod, element(1, T), T2);
{error, not_implemented};
do_encode_transaction(EC, Trans, AsnMod, TransMod, io_list) ->
case do_encode_transaction(EC, Trans, AsnMod, TransMod, binary) of
{ok, Bin} when is_binary(Bin) ->
{ok, Bin};
{ok, DeepIoList} ->
Bin = erlang:list_to_binary(DeepIoList),
{ok, Bin};
{error, Reason} ->
{error, Reason}
end;
do_encode_transaction(EC, _Trans, _AsnMod, _TransMod, _Type) ->
{error, {bad_encoding_config, EC}}.
%%----------------------------------------------------------------------
%% Convert a list of ActionRequest record's into a binary
%% Return {ok, DeepIoList} | {error, Reason}
%%----------------------------------------------------------------------
-spec encode_action_requests(EC :: list(),
ARs :: list(),
AnsMod :: atom(),
TransMod :: atom(),
Type :: atom()) ->
{'ok', binary()} | {'error', any()}.
encode_action_requests([native], _ARs, _AsnMod, _TransMod, binary) ->
%% asn1rt:encode(AsnMod, element(1, T), T);
{error, not_implemented};
encode_action_requests(_EC, _ARs0, _AsnMod, _TransMod, binary) ->
{error, not_implemented};
encode_action_requests(EC, ARs, AsnMod, TransMod, io_list) ->
case encode_action_requests(EC, ARs, AsnMod, TransMod, binary) of
{ok, Bin} when is_binary(Bin) ->
{ok, Bin};
{ok, DeepIoList} ->
Bin = erlang:list_to_binary(DeepIoList),
{ok, Bin};
{error, Reason} ->
{error, Reason}
end;
encode_action_requests(EC, _ARs, _AsnMod, _TransMod, _Type) ->
{error, {bad_encoding_config, EC}}.
%%----------------------------------------------------------------------
%% Convert a ActionRequest record into a binary
%% Return {ok, DeepIoList} | {error, Reason}
%%----------------------------------------------------------------------
-spec encode_action_request(EC :: list(),
AR :: tuple(),
AnsMod :: atom(),
TransMod :: atom(),
Type :: atom()) ->
{'ok', binary()} | {'error', any()}.
encode_action_request([native], _AR, _AsnMod, _TransMod, binary) ->
%% asn1rt:encode(AsnMod, element(1, T), T);
{error, not_implemented};
encode_action_request(_EC, _AR, _AsnMod, _TransMod, binary) ->
{error, not_implemented};
encode_action_request(EC, AR, AsnMod, TransMod, io_list) ->
case encode_action_request(EC, AR, AsnMod, TransMod, binary) of
{ok, Bin} when is_binary(Bin) ->
{ok, Bin};
{ok, DeepIoList} ->
Bin = erlang:list_to_binary(DeepIoList),
{ok, Bin};
{error, Reason} ->
{error, Reason}
end;
encode_action_request(EC, _AR, _AsnMod, _TransMod, _Type) ->
{error, {bad_encoding_config, EC}}.
%%----------------------------------------------------------------------
%% Convert a ActionReply record into a binary
%% Return {ok, DeepIoList} | {error, Reason}
%%----------------------------------------------------------------------
encode_action_reply([native], _ARs, _AsnMod, _TransMod, binary) ->
%% asn1rt:encode(AsnMod, element(1, T), T);
{error, not_implemented};
encode_action_reply(_EC, _ARs0, _AsnMod, _TransMod, binary) ->
{error, not_implemented};
encode_action_reply(EC, ARs, AsnMod, TransMod, io_list) ->
case encode_action_reply(EC, ARs, AsnMod, TransMod, binary) of
{ok, Bin} when is_binary(Bin) ->
{ok, Bin};
{ok, DeepIoList} ->
Bin = erlang:list_to_binary(DeepIoList),
{ok, Bin};
{error, Reason} ->
{error, Reason}
end;
encode_action_reply(EC, _ARs, _AsnMod, _TransMod, _Type) ->
{error, {bad_encoding_config, EC}}.
%%----------------------------------------------------------------------
%% Convert a binary into a 'MegacoMessage' record
%% Return {ok, MegacoMessageRecord} | {error, Reason}
%%----------------------------------------------------------------------
decode_message_dynamic(EC, Bin,
[{AsnModV1, TransModV1},
{AsnModV2, TransModV2},
{AsnModV3, TransModV3}], Form)
when is_list(EC) andalso is_binary(Bin) ->
case AsnModV1:decode_message_version(Bin) of
{ok, PartialMsg} ->
V = (PartialMsg#'MegacoMessage'.mess)#'Message'.version,
case V of
1 ->
decode_message(EC, Bin, AsnModV1, TransModV1, Form);
2 ->
decode_message(EC, Bin, AsnModV2, TransModV2, Form);
3 ->
decode_message(EC, Bin, AsnModV3, TransModV3, Form)
end;
{error, Reason} ->
{error, Reason}
end;
decode_message_dynamic(EC, Bin, _Mods, _Type)
when is_binary(Bin) ->
{error, {bad_encoding_config, EC}};
decode_message_dynamic(_EC, _BadBin, _Mods, _Type) ->
{error, no_binary}.
decode_message(EC, Bin, AsnMod, TransMod, binary) ->
case asn1rt:decode(AsnMod, 'MegacoMessage', Bin) of
{ok, MegaMsg} ->
case EC of
[native] ->
{ok, MegaMsg};
_ ->
{ok, TransMod:tr_message(MegaMsg, decode, EC)}
end;
{error, Reason} ->
{error, Reason}
end;
decode_message(EC, Bin, AsnMod, TransMod, io_list) ->
ShallowIoList = erlang:binary_to_list(Bin),
case asn1rt:decode(AsnMod, 'MegacoMessage', ShallowIoList) of
{ok, MegaMsg} ->
case EC of
[native] ->
{ok, MegaMsg};
_ ->
{ok, TransMod:tr_message(MegaMsg, decode, EC)}
end;
{error, Reason} ->
{error, Reason}
end.
%%----------------------------------------------------------------------
%% Convert a binary into a partial 'MegacoMessage' record
%% I.e. only version and Mid is fully decoded.
%% Return {ok, MegacoMessageRecord} | {error, Reason}
%%----------------------------------------------------------------------
decode_mini_message(_, Bin, Mod, _) ->
case (catch Mod:decode_message_mId(Bin)) of
{ok, #'MegacoMessage'{mess = Mess} = MegaMsg} ->
Mess2 = Mess#'Message'{messageBody = undefined},
{ok, MegaMsg#'MegacoMessage'{mess = Mess2}};
Error ->
Error
end.
decode_mini_message_dynamic(EC, Bin, [Mod1, Mod2, Mod3], Form) ->
case Mod1:decode_message_version(Bin) of
{ok, PartialMsg} ->
V = (PartialMsg#'MegacoMessage'.mess)#'Message'.version,
case V of
1 ->
decode_mini_message(EC, Bin, Mod1, Form);
2 ->
decode_mini_message(EC, Bin, Mod2, Form);
3 ->
decode_mini_message(EC, Bin, Mod3, Form)
end;
Error ->
Error
end.
