.\" Copyright (C) 2010 Romain Tartiere
.\"
.\" This program is free software: you can redistribute it and/or modify it
.\" under the terms of the GNU Lesser General Public License as published by the
.\" Free Software Foundation, either version 3 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 Lesser General Public License
.\" along with this program.  If not, see <http://www.gnu.org/licenses/>
.\"
.\" $Id$
.\"
.Dd March 30, 2010
.Dt TLV 3
.Os
.\"  _   _
.\" | \ | | __ _ _ __ ___   ___
.\" |  \| |/ _` | '_ ` _ \ / _ \
.\" | |\  | (_| | | | | | |  __/
.\" |_| \_|\__,_|_| |_| |_|\___|
.\"
.Sh NAME
.Nm tlv_encode ,
.Nm tlv_decode
.Nd TLV Manipulation Functions
.\"  _     _ _
.\" | |   (_) |__  _ __ __ _ _ __ _   _
.\" | |   | | '_ \| '__/ _` | '__| | | |
.\" | |___| | |_) | | | (_| | |  | |_| |
.\" |_____|_|_.__/|_|  \__,_|_|   \__, |
.\"                               |___/
.Sh LIBRARY
Mifare card manipulation library (libfreefare, \-lfreefare)
.\"  ____                              _
.\" / ___| _   _ _ __   ___  _ __  ___(_)___
.\" \___ \| | | | '_ \ / _ \| '_ \/ __| / __|
.\"  ___) | |_| | | | | (_) | |_) \__ \ \__ \
.\" |____/ \__, |_| |_|\___/| .__/|___/_|___/
.\"        |___/            |_|
.Sh SYNOPSIS
.In freefare.h
.Ft "uint8_t *"
.Fn tlv_encode "const uint8_t type" "const uint8_t *istream" "uint16_t isize" "size_t *osize"
.Ft "uint8_t *"
.Fn tlv_decode "const uint8_t *istream" "uint8_t *type" "uint16_t *size"
.\"  ____                      _       _   _
.\" |  _ \  ___  ___  ___ _ __(_)_ __ | |_(_) ___  _ __
.\" | | | |/ _ \/ __|/ __| '__| | '_ \| __| |/ _ \| '_ \
.\" | |_| |  __/\__ \ (__| |  | | |_) | |_| | (_) | | | |
.\" |____/ \___||___/\___|_|  |_| .__/ \__|_|\___/|_| |_|
.\"                             |_|
.Sh DESCRIPTION
The
.Fn tlv_encode
and
.Fn tlv_decode
functions are helpers to manipulate TLV (Text-Length-Value) data.
.Pp
The
.Fn tlv_encode
function converts the
.Ar isize
bytes long
.Ar istream
message into a TLV stream of type
.Ar type
and set the value of
.Ar osize
to the length of the returned stream.
.Pp
The
.Fn tlv_decode
function converts the
.Ar istream
TLV stream and set the
.Ar type
argument according to the type of the stream, and set the
.Ar size
argument to the length of the returned stream.
.\"  ____      _                                 _
.\" |  _ \ ___| |_ _   _ _ __ _ __   __   ____ _| |_   _  ___  ___
.\" | |_) / _ \ __| | | | '__| '_ \  \ \ / / _` | | | | |/ _ \/ __|
.\" |  _ <  __/ |_| |_| | |  | | | |  \ V / (_| | | |_| |  __/\__ \
.\" |_| \_\___|\__|\__,_|_|  |_| |_|   \_/ \__,_|_|\__,_|\___||___/
.\"
.Sh RETURN VALUES
Both functions return memory allocated using
.Xr malloc 3
which should be reclaimed using
.Xr free 3
after usage.
.\"  ____                    _
.\" / ___|  ___  ___    __ _| |___  ___
.\" \___ \ / _ \/ _ \  / _` | / __|/ _ \
.\"  ___) |  __/  __/ | (_| | \__ \ (_) |
.\" |____/ \___|\___|  \__,_|_|___/\___/
.\"
.Sh SEE ALSO
.Xr freefare 3 ,
.Xr malloc 3 ,
.Xr free 3
.\"     _         _   _
.\"    / \  _   _| |_| |__   ___  _ __ ___
.\"   / _ \| | | | __| '_ \ / _ \| '__/ __|
.\"  / ___ \ |_| | |_| | | | (_) | |  \__ \
.\" /_/   \_\__,_|\__|_| |_|\___/|_|  |___/
.\"
.Sh AUTHORS
.An Romain Tartiere Aq romain@blogreen.org
.An Romuald Conty Aq romuald@libnfc.org