logroller

#!/usr/bin/perl 
#simple tool to help manage log rollover for debugging
#just pipe output to this command, and it will handle saving the 
#last F*L lines of data (F is the number of files, L is the number 
#of lines per file)
#reasonable defaults exist for all options. Call help (-h or --help) for details

use warnings;
use strict;

use constant VERSION=>"this is the verion";
use Getopt::Long;

my($PROGNAME)    = ($0 =~ m|([^/]+)$|);

use vars qw (  $help_requested $version_requested );

my $version='$Id: rolling-log,v 1.3 2012/12/31 17:00:06 washer Exp washer $'; #rcs id
my $version_requested;
my $tee = 0; #tee to stdout
my $showroll = 0; #show file rolling
my $fname="logroll".$$;
my $fcnt=10;	#File Count
my $lpf=10000;	#Lines Per File

my $cnt; #current line number in current output file
my $currentfname;
my $lognum=1;
my $ln;		#current line number
my $fn;		#current file number


Getopt::Long::Configure( 'auto_abbrev', 'bundling', 'ignore_case' );
GetOptions(
	'o|output=s'	=> \$fname,
	'f|fcnt=i'	=> \$fcnt,
	'l|lines=i'	=> \$lpf,
	'r|roll|?'	=> \$showroll,
	't|tee|?'	=> \$tee,
	'v|vesion|?'	=> \$version_requested,
        'h|help|?'  => \$help_requested,

) or $help_requested = 1;

if ($version_requested) {
	print STDERR "$0: $version\n";
	exit(0);
}

if ( $help_requested ){
	print STDERR 	"\t-o|--output\t\tFilename (defaults to logroll)\n",
			"\t-f|--fcnt\t\tNumber of files to save (defaults to 10)\n",
			"\t-l|--lines\t\tLines per file (defaults to 10,000)\n",
			"\t-t|--tee\t\t'Tee' to stdout\n",
			"\t-r|--roll\t\tShow progress as each log file rolls over. Mostly for peace of mind that output is occurring\n",
			"\t-h|--help\t\tThis help screen\n";
	exit(0);
}


$currentfname=sprintf "%s-%09.9d",$fname,$lognum;
open( OUT, ">", $currentfname ) or die "uname to open $currentfname";

while(<>){
	print OUT $_;
	print if $tee;
	$cnt++;
	if ($cnt >= $lpf){
		$cnt=0;
		close OUT;
		$fn++;
		$currentfname=sprintf "%s-%09.9d",$fname,$lognum;
		open( OUT, ">", $currentfname ) or die "uname to open $currentfname";
		print STDERR "opening new file $currentfname " if $showroll;

		if($lognum-$fcnt > 0){
			$currentfname=sprintf "%s-%09.9d",$fname,$lognum-$fcnt;
			unlink $currentfname;
			print STDERR "removing old file $currentfname" if $showroll;

		}

		$lognum++;
		print "\n" if $showroll;


	}
}