#!/usr/bin/perl
#########################################################################################
# Description:  UDEV export pin handler - PArt of HiPi Perl Module distribution
# Created       Tue Mar 05 17:06:44 2013
# svn id        $Id:$
# Copyright:    Copyright (c) 2013 Mark Dootson
# Licence:      This work 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 any later 
#               version.
#########################################################################################

use 5.14.0;
use strict;
use warnings;

our $VERSION ='0.33';

my( $group, $pinpath ) = @ARGV;

given( $pinpath ) {
    when( m/gpiochip\d+$/) {
        update_export_perm('/sys/class/gpio');
    }
    when( m/gpio\d+$/) {
        update_pin_perm($pinpath);
    }
    default {
        # be silent
    }
}

sub update_export_perm {
    my $rootpath = shift;
    my ($name,$passwd,$gid,$members) = getgrnam($group);
    for my $file (qw( export unexport ) ) {
        my $filepath = qq($rootpath/$file);
        chmod(0220, $filepath);
        chown(-1, $gid, $filepath);
    }
}

sub update_pin_perm {
    my $rootpath = shift;
    my ($name,$passwd,$gid,$members) = getgrnam($group);
    chmod(0775, $rootpath);
    chown(-1, $gid, $rootpath);
    for my $file (qw( direction edge value active_low ) ) {
        my $filepath = qq($rootpath/$file);
        chmod(0664, $filepath);
        chown(-1, $gid, $filepath);
    }
}

1;