#!/usr/bin/perl
use warnings;
use strict;
use File::Spec::Functions;


my $dir = '/home/mm/.t_m';
my $name = 'naviga3';
my $max_MB = 95;

mkdir( $dir ) or die "$!" if ! -d $dir;
my $file = catfile( $dir, $name );


sub count_traffic {
	my $dev = '/proc/net/dev';
	my $gesamt = 0;
	my $traffic = 0;
	my $summe = 0;
	my $mb_traffic=0;
	my @date = localtime();
	my $day = $date[3];
	my $month = $date[4] + 1;
	my $year = $date[5] + 1900;
	my $pidofpppd;
	
	if ( ! -f $file ) {
		open( my $fh, '>', $file ) or die "$!";
			print $fh "$day:$month:$year:$traffic\n";
		close( $fh );
	}
	
	open( my $in, '<', $file ) or die "$!";
	while ( <$in> ) {
		$gesamt = $1 if /^$day:$month:$year:(\d+)$/;
	}
	close( $in );
	
	chomp( $pidofpppd = `pidof pppd` );
	kill 15, $pidofpppd if $pidofpppd;
	system( "wvdial &" );

	sub catch_signal { my $pidofwvdial = `pidof wvdial`; kill( 15, $pidofwvdial ); };
	local $SIG{INT} = \&catch_signal;
	local $SIG{QUIT} = \&catch_signal;
	local $SIG{KILL} = \&catch_signal;
	local $SIG{TERM} = \&catch_signal;

	while ( 1 ) {
		chomp( $pidofpppd = `pidof pppd` );
		last if $pidofpppd;
		select( undef, undef, undef, 0.25 );
	}

	while ( 1 ) {
		open( my $proc_net, '<', $dev ) or die "$!";
		while ( <$proc_net> ) {
			if ( $_ =~ /^\s*ppp0:\s+(\d+)(?:\s+\d+){7}\s+(\d+)(?:\s+\d+){7}\s*$/ )
				{
				my $summe = $1 + $2;
				$traffic = $gesamt + $summe;
				$mb_traffic = $traffic / 1048576;
				printf "%.2f\n", $mb_traffic;
				my @d = localtime();
				if ( $d[3] != $day ) {
					$summe=0;
					$gesamt=0;
					$traffic=0;
				}
				if ( $mb_traffic > $max_MB ) {
					$pidofpppd = `pidof pppd`;
					kill 15, $pidofpppd;
					#write_to_file( $traffic );
					exit;
				}
			}
		}
		close( $proc_net );
		select( undef, undef, undef, 0.25 );
		chomp( my $pidofpppd = `pidof pppd` );
		last if ! $pidofpppd;
	}
	END { write_to_file( $traffic ); };
}

count_traffic();