検索結果をアクセスランキング順にソートする方法(3): ナマズのブログ

#!/usr/bin/perl

use CGI;
use Fcntl;
use SDBM_File;
use Config;

sub safe_die($);

my $index = "/usr/local/var/namazu/index";

my $query = new CGI;
my $uri = $query->param('uri');
my $path = $uri;

# Replace
$path =~ s!^http://www.foo.bar.jp/~foo/!/home/foo/public_html/!s;

my $flags = O_CREAT | O_RDWR | BINARY();

tie( %dbhash, 'SDBM_File', "$index/NMZ.sdbm.accessrank", 
        $flags, 0666)
        or safe_die("Cannot open database $!");

chmod 0666, 'NMZ.sdbm.accessrank.dir', 'NMZ.sdbm.accessrank.pag';

if (exists($dbhash{$path})) {
    $dbhash{$path}++ if ($dbhash{$path} != 2147483647);
} else {
    $dbhash{$path} = 1;
}

my $nmz_uri = "$index/NMZ.field.uri";
my $nmz_access_rank = "$index/NMZ.field.accessrank";

open(NMZ_URI, "< $nmz_uri") or safe_die("Cannot open file $!");
binmode NMZ_URI;

open(NMZ_ACCESS_RANK, "> $nmz_access_rank.$$.tmp")
        or safe_die("Cannot open file $!");
binmode NMZ_ACCESS_RANK;

open(NMZ_ACCESS_RANK_I, "> $nmz_access_rank.i.$$.tmp")
        or safe_die("Cannot open file $!");
binmode NMZ_ACCESS_RANK_I;

chmod 0666, "$nmz_access_rank.$$.tmp", 
        "$nmz_access_rank.i.$$.tmp";

my $offset = 0;
while(my $uri = <NMZ_URI>) {
    my $count;

    chomp $uri;
    if (exists($dbhash{$uri})) {
        $count = $dbhash{$uri};
    } else {
        $count = 0;
    }

    printf NMZ_ACCESS_RANK "%-10d\n", $count;
    print NMZ_ACCESS_RANK_I pack('N', $offset);

    $offset += 11;
}

close(NMZ_ACCESS_RANK_I);
close(NMZ_ACCESS_RANK);

rename("$nmz_access_rank.$$.tmp", "$nmz_access_rank");
rename("$nmz_access_rank.i.$$.tmp", "$nmz_access_rank.i");

close(NMZ_URI);

untie( %dbhash );

print "Location: $uri\n\n";

sub BINARY {
    return O_BINARY if $Config{osname} =~ /^(MS)?Win/;
}

sub safe_die($)
{
    my ($msg) = @_;

    open(OUT, ">> $index/error.txt");
    print $msg . "\n";
    close(OUT);

    print "Content-Type: text/plain\n\n";
    print "Error: $msg\n";

    exit 1;
}