Listing 5: Top-level graphlogs.pl which calls other scripts

#!/usr/local/bin/perl -w

#
#  graphlogs.pl -  Top-level script for generating .gif files from log files
#
#    Usage:    graphlogs.pl
#
#    Input:    $StatsDir is the directory containing log files and subscripts
#              $NamedFile contains log file from named daemon
#              $NetstatsFile contains log file from netstat routine
#              GnuPlot is installed at /usr/local/bin/gnuplot
#
#    Output:   Normal operation is silent
#              Creates temporary X,Y data files named.dat and netstats.dat
#              Generates .gif files in $StatsDir (see gnuplot below)
#

require 'ctime.pl';  # For date functions

# Set $StatsDir to the directory containing the log files and sub-scripts
$StatsDir = "/var/stats";
$NamedFile  = "named.messages";          # The log from named
$NetstatsFile = "netstats.messages";     # The log from the netstat
undef $FirstX;                           # collector
$LastX = $StartX = 0;

# Go to where the logs and graphs are
#
chdir($StatsDir);


# Use sub-scripts to parse log files into plottable data
#
unlink("named.dat") if (-e "named.dat");
`named_log_to_stats.pl $NamedFile > named.dat`;

unlink("netstats.dat") if (-e "netstats.dat");
`netstats_log_to_stats.pl $NetstatsFile > netstats.dat`;

# Determine what X-values will display just the last 10 days of data
#
open(NAMED_DAT, "named.dat") || die "graphlogs.pl: Can't open named.dat";
while (<NAMED_DAT>) {
if (!(defined $FirstX)) { ($FirstCtime, $FirstX, $rest) = split(); }
($rest, $LastX, $rest) = split();
}
close(NAMED_DAT);

if (($LastX - $FirstX) < 10) {
$StartX = $FirstX;
} else {
$StartX = $LastX - 10;
}

# Just for decorating the graph's X-axis
#
($wday,$mo,$mday,$time,$rest) = split(/ +/, &ctime($FirstCtime));
$FirstDate = join(' ',$wday,$mo,$mday,$time);

# Write out gnuplot commands to a temporary file
#
open(GNUPLOT_CMD, ">gnuplot.cmd") || die
"graphlogs.pl: Can't open gnuplot.cmd for writing\n";
print GNUPLOT_CMD <<"EOF";
set term gif
set size 0.75,0.75
set nokey
set xlabel "X values are the Nth day since $FirstDate"

set output "rq_per_min.gif"
plot [$StartX:$LastX] "named.dat" using 2:3 with lines

set output "rq_per_hour.gif"
plot [$StartX:$LastX] "named.dat" using 2:4 with lines

set output "rq_total.gif"
plot [$StartX:$LastX] "named.dat" using 2:5 with lines

set xlabel ""
set output "collisions.gif"
plot [$StartX:$LastX] "netstats.dat" using 2:3 with lines

EOF
close(GNUPLOT_CMD);

# Generate the graphs by invoking gnuplot with the command file
#
system("/usr/local/bin/gnuplot gnuplot.cmd");

# End of File