File Coverage

blib/lib/Linux/Info/FileStats.pm

Criterion	Covered	Total	%
statement	49	50	98.0
branch	7	14	50.0
condition			n/a
subroutine	8	8	100.0
pod	2	2	100.0
total	66	74	89.1

package Linux::Info::FileStats;
use strict;
use warnings;
use Carp qw(croak);
our $VERSION = '1.3'; # VERSION

=head1 NAME

Linux::Info::FileStats - Collect linux file statistics.

=head1 SYNOPSIS

    use Linux::Info::FileStats;

    my $lxs  = Linux::Info::FileStats->new;
    my $stat = $lxs->get;

=head1 DESCRIPTION

Linux::Info::FileStats gathers file statistics from the virtual F filesystem (procfs).

For more information read the documentation of the front-end module L.

=head1 FILE STATISTICS

Generated by F, F and F.

    fhalloc    -  Number of allocated file handles.
    fhfree     -  Number of free file handles.
    fhmax      -  Number of maximum file handles.
    inalloc    -  Number of allocated inodes.
    infree     -  Number of free inodes.
    inmax      -  Number of maximum inodes.
    dentries   -  Dirty directory cache entries.
    unused     -  Free diretory cache size.
    agelimit   -  Time in seconds the dirty cache entries can be reclaimed.
    wantpages  -  Pages that are requested by the system when memory is short.

If youre looking for information about inodes usage in a mouint point, most probably you want to take a look at L module.
This module gets information about inodes from /proc as L does, but documentation about this specific part of /proc is obscure,
so you're on your own to find out which module to use.

=head1 METHODS

=head2 new()

Call C to create a new object.

    my $lxs = Linux::Info::FileStats->new;

It's possible to set the path to the proc filesystem.

     Linux::Info::FileStats->new(
        files => {
            # This is the default
            path     => '/proc',
            file_nr  => 'sys/fs/file-nr',
            inode_nr => 'sys/fs/inode-nr',
            dentries => 'sys/fs/dentry-state',
        }
    );

=head2 get()

Call C to get the statistics. C returns the statistics as a hash reference.

    my $stat = $lxs->get;

=head1 EXPORTS

Nothing.

=head1 SEE ALSO

=over

=item *

B

=item *

L

=item *

L

=back

=head1 AUTHOR

Alceu Rodrigues de Freitas Junior, [e-mail]

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2015 of Alceu Rodrigues de Freitas Junior, [e-mail]

This file is part of Linux Info project.

Linux-Info is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Linux-Info is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Linux Info.  If not, see .

=cut

sub new {
    my $class = shift;
    my $opts  = ref($_[0]) ? shift : {@_};

    my %self = (
        files => {
            path     => '/proc',
            file_nr  => 'sys/fs/file-nr',
            inode_nr => 'sys/fs/inode-nr',
            dentries => 'sys/fs/dentry-state',
        }
    );

    foreach my $file (keys %{ $opts->{files} }) {
        $self{files}{$file} = $opts->{files}->{$file};
    }

    return bless \%self, $class;
}

sub get {
    my $self  = shift;
    my $class = ref $self;
    my $file  = $self->{files};
    my $stats = { };

    $self->{stats} = $stats;
    $self->_get_file_nr;
    $self->_get_inode_nr;
    $self->_get_dentries;

    return $stats;
}

sub _get_file_nr {
    my $self  = shift;
    my $class = ref $self;
    my $file  = $self->{files};
    my $stats = $self->{stats};

    my $filename = $file->{path} ? "$file->{path}/$file->{file_nr}" : $file->{file_nr};
    open my $fh, '<', $filename or croak "$class: unable to open $filename ($!)";
    @$stats{qw(fhalloc fhfree fhmax)} = (split /\s+/, <$fh>)[0..2];
    close($fh);
}

sub _get_inode_nr {
    my $self  = shift;
    my $class = ref $self;
    my $file  = $self->{files};
    my $stats = $self->{stats};

    my $filename = $file->{path} ? "$file->{path}/$file->{inode_nr}" : $file->{inode_nr};
    open my $fh, '<', $filename or croak "$class: unable to open $filename ($!)";
    @$stats{qw(inalloc infree)} = (split /\s+/, <$fh>)[0..1];
    $stats->{inmax} = $stats->{inalloc} + $stats->{infree};
    close($fh);
}

sub _get_dentries {
    my $self  = shift;
    my $class = ref $self;
    my $file  = $self->{files};
    my $stats = $self->{stats};

    my $filename = $file->{path} ? "$file->{path}/$file->{dentries}" : $file->{dentries};
    open my $fh, '<', $filename or croak "$class: unable to open $filename ($!)";
    @$stats{qw(dentries unused agelimit wantpages)} = (split /\s+/, <$fh>)[0..3];
    close($fh);
}

1;