Thanks for the suggestions. Directory traversals with .. don't work. I checked it when I wrote the code. Patched up the code while keeping the other suggestions in mind. Pasting the updated code: 
#!/usr/local/bin/perl -w

#Caution: Big mess ahead
#TODO: 
#   get .. working in dir listing
#   implement Getopt::Long
#   usage() function
#   log to syslog
#   fork() children
#   daemonize 
#   persistent connections

use strict;
use IO::Socket;

my ($socket, @files, $req, $client);

my $DOCROOT = '/home/arun/docs/';
my %error_page = (
    403 => $DOCROOT.'403.html', # forbidden
    404 => $DOCROOT.'404.html', # not found
    406 => $DOCROOT.'406.html', # not acceptable
    501 => $DOCROOT.'501.html'  # not implemented
);

#$SIG{'INT'} = \&cleanup;

$socket = new IO::Socket::INET (
    LocalAddr => '127.0.0.1',
    LocalPort => (shift || 4321),
    Proto     => 'tcp',
    Listen    => 5,
    ReuseAddr => 1
) or die "$! \n";

$socket->listen();
&log("Listening on ".$socket->sockhost().":".$socket->sockport."\n");

while ($client = $socket->accept()) {
    &log("Connection from ".$client->peerhost().":".$client->peerport(
+)."\n");

    # get http request - first line
    $req = <$client>;
    &log($client->peerhost()." ".$req);
    &respond_to( &handle_req($req) );

    close $client;
}

sub cleanup { close $socket; die "Interrupted. Exiting...\n"; }
sub log {
    my $msg = shift;
    print scalar localtime," ", $msg;
}
sub getfiles {
    my $dir = shift;
    opendir DIR, $dir or die "open:$!\n";
    # remove . and .. from list of files
    @files = grep { !/^\.(\.)?$/ } readdir DIR;
    closedir DIR;
    return \@files;
}
sub handle_req {
    my ($method, $uri) = split / +/, shift;

    if ($method !~ /^GET/) {
        &log("501 Not Implemented\nr");
        return 501;
    }

    $uri =~ s/\/(.*)/$1/;                               # strip the fi
+rst slash

    if (-e $DOCROOT.$uri) {
        if (-f $DOCROOT.$uri) {
            &log("200 HTTP OK\n");
            return 200;
        } elsif (-d $DOCROOT.$uri) {
            &log("200 HTTP OK\n");
            return 200;
        } else {
            &log("406 Not Acceptable\n");
            return 406;
        }
    }
    &log("404 Not Found\n");
    return 404;
}
sub respond_to {
    my $status_code = shift;
    unless ($status_code == 200) {
        &display($error_page{$status_code}) if (-f $error_page{$status
+_code});
        return;
    }

    my $uri = (split / +/, $req)[1];
    $uri =~ s/\/(.*)/$1/;
    chomp($uri);

    my $path = $DOCROOT.$uri;
    if (-f $path) {
        &display($path) ;
        return;
    }
    if (-d $path) {
        if (-f $path.'index.html') {
            &display($path.'index.html');
        } else {
            &gen_dir_list($uri, &getfiles($path));
        }
    }
    return;
}
sub display {
    my $file = shift;
    open RES, $file or die "open: $file: $!";
    &log("Sending $file\n");
    print $client $_ while (<RES>);
    close RES;
}
sub gen_dir_list {
    my ($uri, $files) = @_;
    &log("[info] dir listing request\n");

    # print html header
    print $client <<HEADER;
    <html>
        <head><title>dir listing for: /$uri</title></head>
        <body>
        <table cellpadding=5>
HEADER

    my $count;
    foreach my $f (@$files) {
        printf $client "%s<td><a href=\"%s\">%s</a></td><td>%s</td></t
+r>",
                # different colours for alternate rows
                (++$count % 2 ? '<tr bgcolor="#e0ffd6">' : '<tr bgcolo
+r="#ffdcd6">'),
                # genereate href links
                (-d $DOCROOT.$uri.'/'.$f ?  '/'.$uri.$f.'/' : '/'.$uri
+.$f),
                # append a '/' to the end of dirs
                (-d $DOCROOT.$uri.'/'.$f ?  $f.'/' : $f),
                scalar localtime((stat $DOCROOT.$uri.'/'.$f)[9]);
    }

    #print html footer
    print $client <<FOOTER;
    </table>
    <p>-- httpserv v0.1 --</p>
    </body>
    </html>
FOOTER
}

[download]

Thanks for the percritic link. It did find many things. Am still working on it. I will also remove & from function calls.

In reply to Re: how to improve my script by agn
in thread how to improve my script by agn

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