#!/usr/bin/perl
#
# Reads the display filter keyword dump produced by 'tshark -G' and
# formats it for a pod document. The pod document is then used to
# make a manpage
#
# STDIN is the wireshark glossary
# arg1 is the pod template file. The =insert_dfilter_table token
#      will be replaced by the pod-formatted glossary
# STDOUT is the output
#
# Gilbert Ramirez <gram [AT] alumni.rice.edu>
#
# Wireshark - Network traffic analyzer
# By Gerald Combs <gerald@wireshark.org>
# Copyright 1998 Gerald Combs
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# 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 General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

use Getopt::Std;

%ftenum_names = (
	'FT_NONE',		'No value',
	'FT_PROTOCOL',		'Protocol',
	'FT_BOOLEAN',		'Boolean',
	'FT_UINT8',		'Unsigned 8-bit integer',
	'FT_UINT16',		'Unsigned 16-bit integer',
	'FT_UINT24',		'Unsigned 24-bit integer',
	'FT_UINT32',		'Unsigned 32-bit integer',
	'FT_UINT64',		'Unsigned 64-bit integer',
	'FT_INT8',		'Signed 8-bit integer',
	'FT_INT16',		'Signed 16-bit integer',
	'FT_INT24',		'Signed 24-bit integer',
	'FT_INT32',		'Signed 32-bit integer',
	'FT_INT64',		'Signed 64-bit integer',
	'FT_FLOAT',		'Single-precision floating point',
	'FT_DOUBLE',		'Double-precision floating point',
	'FT_ABSOLUTE_TIME',	'Date/Time stamp',
	'FT_RELATIVE_TIME',	'Time duration',
	'FT_STRING',		'String',
	'FT_STRINGZ',		'NULL terminated string',
	'FT_EBCDIC',		'EBCDIC string',
	'FT_UINT_STRING',	'Length string pair',
	'FT_ETHER',		'6-byte Hardware (MAC) Address',
	'FT_BYTES',		'Byte array',
	'FT_UINT_BYTES',	'Length byte array pair',
	'FT_IPv4',		'IPv4 address',
	'FT_IPv6',		'IPv6 address',
	'FT_IPXNET',		'IPX network or server name',
	'FT_FRAMENUM',		'Frame number',
	'FT_PCRE',		'Perl Compatible Regular Expression',
	'FT_GUID',		'Globally Unique Identifier',
	'FT_OID',		'Object Identifier',
	'FT_REL_OID',		'Relative Object Identifier',
);

getopts('e');

if ($opt_e) {
	$proto_abbrev{'Unable to generate filter documentation'} =
		'Please refer to https://www.wireshark.org/docs/dfref/';
	printf STDERR "Creating empty filter list.\n";
} else {
	# Read all the data into memory
	while (<STDIN>) {
		next unless (/^([PF])/);
	
		$record_type = $1;
		# Strip the line from its line-end sequence
		# chomp($_) won't work on Win32/CygWin as it leaves the '\r' character.
		$_ =~ s/[\r\n]//g;
	
		# Store protocol information
		if ($record_type eq 'P') {
			($junk, $name, $abbrev) = split(/\t+/, $_);
			$proto_abbrev{$name} = $abbrev;
		}
		# Store header field information
		else {
			($junk, $name, $abbrev, $type, $parent, $blurb) =
				split(/\t+/, $_);
			push(@{$field_abbrev{$parent}}, $abbrev);
			$field_info{$abbrev} = [ $name, $type, $blurb ];
		}
	}
}

# if there was no input on stdin, bail out
if ($record_type ne 'P' and $record_type ne 'F' and !defined($opt_e)) {
	exit;
}

$template = shift(@ARGV);

open(TEMPLATE, $template) || die "Can't open $template for reading: $!\n";

while (<TEMPLATE>) {
	if (/=insert_dfilter_table/) {
		&create_dfilter_table;
	}
	else {
		print;
	}
}

close(TEMPLATE) || die "Can't close $template: $!\n";

sub create_dfilter_table {

	# Print each protocol
	for $proto_name (sort keys %proto_abbrev) {

		print "=head2 $proto_name ($proto_abbrev{$proto_name})\n\n";

		# If this proto has children fields, print those
		if ($field_abbrev{$proto_abbrev{$proto_name}}) {

			for $field_abbrev (sort @{$field_abbrev{$proto_abbrev{$proto_name}}}) {
				print "    $field_abbrev  ", $field_info{$field_abbrev}[0],"\n",
				      "        ", $ftenum_names{$field_info{$field_abbrev}[1]},
				   "\n";
				print "        ", $field_info{$field_abbrev}[2], "\n"
					if $field_info{$field_abbrev}[2];
				print "\n";
			}
		}
	}
}