253 lines
8.4 KiB
Groff
253 lines
8.4 KiB
Groff
.\"
|
|
.\" Copyright (c) 2001-2003
|
|
.\" Fraunhofer Institute for Open Communication Systems (FhG Fokus).
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" Author: Hartmut Brandt <harti@freebsd.org>
|
|
.\"
|
|
.\" $Begemot: libunimsg/man/unifunc.3,v 1.2 2003/08/21 16:01:08 hbb Exp $
|
|
.\"
|
|
.Dd October 30, 2003
|
|
.Dt unifunc 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm libngatm
|
|
.Nm uni_decode
|
|
.Nm uni_decode_head
|
|
.Nm uni_decode_body
|
|
.Nm uni_decode_ie_hdr
|
|
.Nm uni_decode_ie_body
|
|
.Nm uni_encode
|
|
.Nm uni_encode_msg_hdr
|
|
.Nm uni_encode_ie
|
|
.Nm uni_encode_ie_hdr
|
|
.Nm uni_check_ie
|
|
.Nm uni_print_cref
|
|
.Nm uni_print_msghdr
|
|
.Nm uni_print
|
|
.Nm uni_print_ie
|
|
.Nm uni_initcx
|
|
.Nm uni_print_cx
|
|
.Nd "ATM signalling library - message handling functions"
|
|
.Sh LIBRARY
|
|
Begemot ATM signalling library
|
|
.Pq libngatm, -lngatm
|
|
.Sh SYNOPSIS
|
|
.In netnatm/msg/unistruct.h
|
|
.In netnatm/msg/unimsglib.h
|
|
.Ft int
|
|
.Fn uni_decode "struct uni_msg *buf" "struct uni_all *msg" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_decode_head "struct uni_msg *buf" "struct uni_all *msg" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_decode_body "struct uni_msg *buf" "struct uni_all *msg" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_decode_ie_hdr "enum uni_ietype *type" "struct uni_iehdr *hdr" "struct uni_msg *buf" "struct unicx *cx" "u_int *ielen"
|
|
.Ft int
|
|
.Fn uni_decode_ie_body "enum uni_ietype type" "union uni_ieall *ie" "struct uni_msg *buf" "u_int ielen" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_encode "struct uni_msg *buf" "struct uni_all *msg" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_encode_msg_hdr "struct uni_msg *buf" "struct uni_msghdr *hdr" "enum uni_msgtype type" "struct unicx *cx" "int *mlen"
|
|
.Ft int
|
|
.Fn uni_encode_ie "enum uni_ietype type" "struct uni_msg *buf" "union uni_ieall *ie" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_encode_ie_hdr "struct uni_msg *buf" "enum uni_ietype type" "struct uni_iehdr *hdr" "u_int len" "struct unicx *cx"
|
|
.Ft int
|
|
.Fn uni_check_ie "enum uni_ietype type" "union uni_ieall *ie" "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_print_cref "char *buf" "size_t buflen" "struct uni_cref *cref" "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_print_msghdr "char *buf" "size_t buflen" "struct uni_msghdr *hdr" "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_print "char *buf" "size_t buflen" "struct uni_all *msg" "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_print_ie "char *buf" "size_t buflen" "enum uni_ietype type" "union uni_ieall *ie" "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_initcx "struct unicx *cx"
|
|
.Ft void
|
|
.Fn uni_print_cx "char *buf" "size_t buflen" "struct unicx *cx"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
library handles UNI 4.0 messages.
|
|
For each information element and message
|
|
type the header files contain a structure definition.
|
|
Additionally there
|
|
are a number of help structures and a global context structure for some
|
|
of the library functions.
|
|
This document describes the functions that are
|
|
used to handle messages.
|
|
.Ss DECODING
|
|
Decoding is the process of taking an octet stream containing a UNI message
|
|
or IE, parsing it and filling in a message or IE structure.
|
|
.Pp
|
|
The function
|
|
.Fn uni_decode
|
|
takes a message buffer, interprets it as a UNI message and fills in the
|
|
structure pointed to by
|
|
.Fa msg .
|
|
It also takes a context argument and may fill the error array in the context.
|
|
It returns -1 if there is an error decoding the message header and
|
|
-2 if there is an error decoding the message body.
|
|
The function returns 0 on success.
|
|
.Pp
|
|
The process of decoding a message can be split up by calling
|
|
.Fn uni_decode_head
|
|
and
|
|
.Fn uni_decode_body .
|
|
The first of these functions decodes only the message header and the second
|
|
one decodes only the information elements.
|
|
.Fn uni_decode_head
|
|
returns 0 if it could decode the message header
|
|
and -1 if the message could not be decoded (bad protocol
|
|
identifier, bad length or broken call reference).
|
|
.Fn uni_decode_body
|
|
return 0 on success and -1 for unknown message types or if any
|
|
IE had an error.
|
|
.Pp
|
|
The function
|
|
.Fn uni_decode_ie_hdr
|
|
decodes the next information element header.
|
|
It returns the IE type and its length
|
|
in the variables pointed to by
|
|
.Va type
|
|
and
|
|
.Va ielen
|
|
and stores the decoded header in the structure pointed to by
|
|
.Va hdr .
|
|
The function returns 0 on success and -1 if there were not enough bytes
|
|
in the buffer left for a complete IE header.
|
|
.Pp
|
|
The function
|
|
.Fn uni_decode_ie_body
|
|
decodes the body of an information element. It is passed the buffer with the
|
|
message
|
|
.Fa buf ,
|
|
the information element type
|
|
.Fa type
|
|
and length
|
|
.Fa ielen .
|
|
The IE is stored in the union pointed to by
|
|
.Fa ie .
|
|
The function returns -1 on errors and 0 on success.
|
|
In any case the most correct
|
|
number of bytes is consumed from the input buffer.
|
|
.Ss ENCODING
|
|
Encoding is the process of taking a message or IE structure and producing
|
|
an octet stream from it.
|
|
.Pp
|
|
The function
|
|
.Fn uni_encode
|
|
encodes a UNI message.
|
|
It returns -1 if the message type is out of bounds, -3
|
|
if the message type is unknown.
|
|
The encoding functions for the message types
|
|
can return their own error codes.
|
|
The function returns 0 on success.
|
|
.Pp
|
|
The function
|
|
.Fn uni_encode_msg_hdr
|
|
encodes a message header.
|
|
The variable pointed to by
|
|
.Fa mlen
|
|
is set to the offset of the message length field from the begin of the
|
|
byte stream.
|
|
This is needed because the length of the message body will
|
|
be known only after all the IEs have been encoded.
|
|
Then the length
|
|
has to be inserted into this place.
|
|
The function returns -1 if the call reference
|
|
was bad and 0 on success.
|
|
.Pp
|
|
The function
|
|
.Fn uni_encode_ie
|
|
encodes one information element.
|
|
The function returns 0 on success or -1
|
|
on errors.
|
|
The function
|
|
.Fn uni_encode_ie_hdr
|
|
encodes the four byte IE header.
|
|
The argument
|
|
.Fa len
|
|
is the maximum expected length of the information element, not the real length.
|
|
The function inserts a 0 in the real length field.
|
|
This must be
|
|
fixed up by the caller after encoding the IE contents.
|
|
The function
|
|
return -1 if an empty IE is to be encoded (in this case the length field will
|
|
have been set to 4) or 0 otherwise.
|
|
.Ss CHECKING
|
|
There exists a number of function that do consistency checks on information
|
|
elements.
|
|
Note, that these functions do not check inter-IE consistency, but
|
|
each IE by itself.
|
|
.Pp
|
|
The function
|
|
.Fn uni_check_ie
|
|
check an information element for consistency.
|
|
It returns 0 if the IE seems
|
|
ok, -1 otherwise.
|
|
.Ss PRINTING
|
|
A number of functions can be used to print decoded messages and IEs in
|
|
a human readable form.
|
|
This is intended mainly for debugging.
|
|
Some fields of the library context are used to control how the printing is done
|
|
(see
|
|
.Xr unistruct 3 ).
|
|
Each of the function takes a
|
|
.Fa buf
|
|
and a
|
|
.Fa buflen
|
|
argument.
|
|
The string that is generated in the buffer pointed to by
|
|
.Fa buf
|
|
is guaranteed to be NUL terminated.
|
|
.Pp
|
|
The function
|
|
.Fn uni_print_cref
|
|
formats a call reference taking into account special call references.
|
|
The function
|
|
.Fn uni_print_msg_hdr
|
|
formats a message header.
|
|
The functions
|
|
.Fn uni_print
|
|
and
|
|
.Fn uni_print_ie
|
|
print messages and information elements.
|
|
.Ss CONTEXTS
|
|
There are two functions for context handling.
|
|
.Fn uni_initcx
|
|
initializes a context with default values and
|
|
.Fn uni_print_cx
|
|
prints a context to the given buffer.
|
|
.Sh SEE ALSO
|
|
.Xr libngatm 3
|
|
.Sh STANDARDS
|
|
This implementation conforms to the applicable ITU-T
|
|
recommendations and ATM Forum standards with the exception of some limitations
|
|
(see the Configuration section).
|
|
.Sh AUTHORS
|
|
.An Hartmut Brandt Aq harti@freebsd.org
|