File Coverage

blib/lib/Net/SnoopLog.pm

Criterion	Covered	Total	%
statement	55	68	80.8
branch	5	8	62.5
condition	1	3	33.3
subroutine	6	11	54.5
pod	8	9	88.8
total	75	99	75.7

#!/bin/perl -w
#
# SnoopLog.pm - Net::SnoopLog library to read snoop ver 2 files (RFC1761).
#
# 17-Oct-2003	Brendan Gregg

package Net::SnoopLog;

use strict;
use vars qw($VERSION);

$VERSION = '0.12';

# new - create the snoop object
#
sub new {
	my $proto = shift;
	my $class = ref($proto) || $proto;
	my $self = {};

	$self->{version} = undef;
	$self->{datalink} = undef;
	$self->{data} = [];
	$self->{length_orig} = [];
	$self->{length_inc} = [];
	$self->{drops} = [];
	$self->{seconds} = [];
	$self->{msecs} = [];
	$self->{count} = 0;

	bless($self,$class);
	return $self;
}

# read - read the snoop file into memory
#
sub read {
	my $self = shift;
	my $file = shift;
	my ($header,$length,$ident,$version,$datalink,$header_rec,
	 $record_length_orig,$record_length_inc,$record_length_rec,
	 $record_drops,$record_seconds,$record_msecs,$record_data,$skip,$pad);
	$self->{count} = 0;
	my $num = 0;

	### Open snoop file
	open(SNOOPFILE,"$file") ||
	 die "ERROR: Can't read snoop log $file: $!\n";
	binmode(SNOOPFILE);		# backward OSs

	### Fetch snoop header
	$length = read(SNOOPFILE,$header,16);
	die "ERROR: Can't read from snoop log $file\n" if $length < 16;

	### Check file really is a snoop file
	($ident,$version,$datalink) = unpack('A8NN',$header);
	die "ERROR: Not a snoop file $file\n" if $ident ne "snoop";

	### Store values
	$self->{version} = $version;
	$self->{datalink} = $datalink;

	#
	#  Read all packets into memory
	#
	$num = 0;
	while (1) {
		### Fetch record header
		$length = read(SNOOPFILE,$header_rec,24);

		### Quit loop if at end of file
	        last if $length < 24;

		### Unpack header
        	($record_length_orig,$record_length_inc,$record_length_rec,
		 $record_drops,$record_seconds,$record_msecs) =
		 unpack('NNNNNN',$header_rec);

		### Skip padding
		$length = read(SNOOPFILE,$record_data,$record_length_inc);
		$skip = read(SNOOPFILE,$pad,($record_length_rec -
		 $record_length_inc - 24));

		### Store values in memory
		$self->{data}[$num] = $record_data;
		$self->{length_orig}[$num] = $record_length_orig;
		$self->{length_inc}[$num] = $record_length_inc;
		$self->{drops}[$num] = $record_drops;
		$self->{seconds}[$num] = $record_seconds;
		$self->{msecs}[$num] = $record_msecs;
		$self->{count}++;
		$num++;
	}

	close SNOOPFILE;
}

# indexes - return a list of index numbers for the packets.
#		indexes start at "0"
#
sub indexes {
	my $self = shift;
	my $max = $self->{count} - 1;
	return (0..$max);
}

# maxindex - return the index number for the last packet.
#		indexes start at "0"
#
sub maxindex {
	my $self = shift;
	my $max = $self->{count} - 1;
	return $max;
}

# header - return header data for a given index
#
sub header {
	my $self = shift;
	my $num = shift;
	return ($self->{length_orig}[$num],
		$self->{length_inc}[$num],
		$self->{drops}[$num],
		$self->{seconds}[$num],
		$self->{msecs}[$num]);
}

# data - return packet data for a given index
#
sub data {
	my $self = shift;
	my $num = shift;
	return $self->{data}[$num];
}

# version - return snoop file version
#
sub version {
	my $self = shift;
	return sprintf("%u",$self->{version});
}

# datalink - return snoop datalink type
#
sub datalink {
	my $self = shift;
	return sprintf("%u",$self->{datalink});
}

# clear - clear snoop file from memory
#
sub clear {
	my $self = shift;
	delete $self->{data};
	$self
}


1;
__END__