#!/usr/bin/perl
#
# count_pf.perl5 -- run lsof in repeat mode and count processes and
# files

sub interrupt { print "\n"; exit 0; }

$RPT = 15; # lsof repeat time

# Set path to lsof.

if (($LSOF = &isexec("../lsof")) eq "") { # Try .. first
if (($LSOF = &isexec("lsof")) eq "") { # Then try . and $PATH
print "can't execute $LSOF\n"; exit 1
}
}

# Read lsof -nPF0 output repeatedly from a pipe.

$| = 1; # unbuffer output
$SIG{'INT'} = 'interrupt'; # catch interrupt
$proc = $files = $tcp = $udp = 0;
$progress="/";
open(P, "$LSOF -nPF0 -r $RPT|") || die "can't open pipe to $LSOF\n";

LSOF_LINE:

while (<P>) {
chop;
if (/^m/) {

# A marker line signals the end of an lsof repetition.

printf "%s Processes: %5d, Files: %6d, TCP: %6d, UDP: %6d\r",
$progress, $proc, $files, $tcp, $udp;
$proc = $files = $tcp = $udp = 0;
if ($progress eq "/") { $progress = "\\"; } else { $progress = "/"; }
next LSOF_LINE;
}
if (/^p/) {

# Count process.

$proc++;
next LSOF_LINE;
}
if (/^f/) {

# Count files.

$files++;
@F = split("\0", $_, 999);
foreach $i (0 .. ($#F - 1)) {

# Search for protocol field.

if ($F[$i] =~ /^P(.*)/) {

# Count instances of TCP and UDP protocols.

if ($1 eq "TCP") { $tcp++; }
elsif ($1 eq "UDP") { $udp++; }
next LSOF_LINE;
}
}
}
}


## isexec($path) -- is $path executable
#
# $path = absolute or relative path to file to test for executabiity.
# Paths that begin with neither '/' nor '.' that arent't found as
# simple references are also tested with the path prefixes of the
# PATH environment variable.

sub
isexec {
my ($path) = @_;
my ($i, @P, $PATH);

$path =~ s/^\s+|\s+$//g;
if ($path eq "") { return(""); }
if (($path =~ m#^[\/\.]#)) {
if (-x $path) { return($path); }
return("");
}
$PATH = $ENV{PATH};
@P = split(":", $PATH);
for ($i = 0; $i <= $#P; $i++) {
if (-x "$P[$i]/$path") { return("$P[$i]/$path"); }
}
return("");
}