#!/usr/bin/perl -I/HIDDEN_FOR_INFN_SECURITY

use Time::HiRes qw ( time alarm sleep );
use Getopt::Long;
$| = 1;

$interval = 0.5 ;# seconds, float
$track = 0;
$maxtr = 100;
$barlen = 25;
$iface = 'eth';

#( $iface = $ARGV[0] ) =~ s/\d+$//;


$help = '
Usage: netspeed -i=<interface> [OPTIONS]
Example: netspeed -i=eth[0-9] -p=10240 -b=12 -d=0.5 -f=/tmp/if_speeds.log


  -i, --interface=REGEXP          Net interface to listen to.
  -f, --log-file=FILENAME         Log speeds to a file.
  -p, --print-trace=MBITS         Trace speeds above the specified limit
  -d, --delay=SECONDS             Refresh every n seconds (float).
  -b, --bandwidth=MBITS           Max speed of interfaces.
  -u, --upbandwidth=MBITS         Max upload speed of interfaces.
  -h, --help                      Print this help.
  
';

GetOptions ( 'interface=s'     => \$iface,
             'file-log=s'      => \$logfile,
             'print-trace=i'   => \$track,
             'delay=f'         => \$interval,
             'bandwidth=f'     => \$maxtr,
             'upbandwidth=f'   => \$maxtrup,
             'help'            => sub{ print $help; exit; } 
           );

#print "iface: $iface, logfile: $logfile, track: $track, interval: $interval\n";

$maxtrup = $maxtr unless $maxtrup;
$track = $track *1024 if $track;

unless ($iface) {
    print $help;
    exit;
}

`resize`;
$termwidth = $ENV{'COLUMNS'};
$termwidth = 80 unless $termwidth;

if ( !$termwidth ) {
     `resize`  =~ /COLUMNS=(\d+)/;
     $termwidth = $1;
}

( $barlen = ( $termwidth - length($iface) - 26 ) / 2 ) =~ s/\..*//g;

printf "\n%-".length($iface)."s | %-".(6+3+$barlen)."s | %-".(6+3+$barlen)."s |\n", "if", "Kb/s RX" , "Kb/s TX";
$lastover = time();       

#unless ( sleep(0.1) ) {
#    print "Time::HiRes not found. Interval not float.\n";
#    $interval=1;
#}

while ( 1 ) {

    sleep($interval);
                
    $kbin = $kbout = $pksin = $pksout = 0;
    open( COUNTERS, "</proc/net/dev" );
    while ( <COUNTERS> ) {
        if ( /^.*$iface(.*):\s*(\d+)\s*(\d+)(\s*\d+){6}\s*(\d+)\s*(\d+)(\s*\d+){6}/ ) {
            $kbin   += $2/1024*8;
            $kbout  += $5/1024*8;
            $pksin  += $3;
            $pksout += $6;
        }
    }
    close(COUNTERS);

    if (!$kbinold && !$kboutold) {
        $kbinold = $kbin;
        $kboutold = $kbout;
        next;
    }
    $kbSin  = ( $kbin  - $kbinold  ) / $interval;
    $kbSout = ( $kbout - $kboutold ) / $interval;

    $kbSin  = 0 if $kbSin  < 0;
    $kbSout = 0 if $kbSout < 0;
 
    $barIN = '';
    for ($b=1 ; $b <= ($kbSin/1024/$maxtr*$barlen) ; $b++) {
        $barIN .= '#';
        last if $b >= $barlen;
    }

    $barOUT = '';
    for ($b=1 ; $b <= ($kbSout/1024/$maxtrup*$barlen) ; $b++) {
        $barOUT .= '#';
        last if $b >= $barlen;
    }

    printf "%-".length($iface)."s | %6d #%-${barlen}s# | %6d #%-${barlen}s# |", $iface, $kbSin, $barIN, $kbSout, $barOUT ;

    $nowtime = localtime ;

    if ( $track && ( $kbSin >= $track || $kbSout >= $track ) ) {
        print  "\n^^^^ at $nowtime ^^^^\n" ;
        $nowtime = '^^^^^^^^^^^^^^^^^^^^^^^^' if $lastover+1 >= time();
        $lastover = time();
        if ( $logfile ) {
            open( LOG, ">>$logfile" );
            printf LOG "$iface: kB  Rx: %10d / Tx: %10d  -  at %s \n", $kbSin, $kbSout, $nowtime;
            close( LOG ) ;
        }

    } else {
        print "\r";
    }

    $kbinold = $kbin;
    $kboutold = $kbout;
}