initify.pl

#!/usr/bin/perl
# (c) goose121, 2017
# Released under the MIT license

use warnings;
#use strict;
use v5.10.1;
use feature "switch";
use Getopt::Long;
use Pod::Usage;

my $type = "simple";
my @cmds_start = ();
my @cmds_stop = ();
my $pidfile = "";
my $desc = "";

# parse CLI args
my %opt;
GetOptions(\%opt,
           "name=s",
           "help|?") || pod2usage(2);
pod2usage() if ($opt{help});

# sanity checks
my $USAGE = "Usage: initify [options] some-systemd.service";
unless (@ARGV > 0 && $ARGV[0] =~ /(.*\/)?([^\/.]*)\.service/) {
    print "no *.service file specified - quitting\n$USAGE\n";
    exit;
}
unless (-e "$ARGV[0]") {
    print "can not find *.service file: '$ARGV[0]' - quitting\n$USAGE\n";
    exit;
}

# get systemd service source file, and target service name
(my $service = $ARGV[0])=~s/\.service//;
(my $svc_name = $ARGV[0])=~s|(.*/)?([^/.]*)\.service|$2|;
$svc_name = $opt{name} if (length $opt{name});

# begin
while(<>) {
    #s/\s*|\s*$//g; # Trim whitespace
    if (m/^Type\s*=\s*(.*)/) {
        $type=$1;
    }
    if (m/^ExecStart\s*=\s*(.*)/) {
        if (length $1) {
            push(@cmds_start, $1);
        }
        else {
            @cmds_start = (); # If the line is "ExecStart=",
                              # it means to clear ExecStart.
        }
    }
    if (m/^ExecStop\s*=\s*(.*)/) {
        if (length $1) {
            push(@cmds_stop, $1);
        }
        else {
            @cmds_stop = (); # If the line is "ExecStop=",
                             # it means to clear ExecStop.
        }
    }
    if (m/^PIDFile=(.*)/) {
        if(length $1) {
            $pidfile = $1;
        }
    }
    if (m/^Description=(.*)/) {
        $desc = $1
    }
}

my @cmds;

my @cmd_path;
my @cmd_argl;

map {my @sep = split(/ /, $_, 2);
     push(@cmd_path, $sep[0]);
     push(@cmd_argl, $sep[1]);
} @cmds_start;

open(FH, '>', "$service") || die("Cannot create $service: $!\n");

print FH <<"EOF";
\#!/sbin/openrc-run

command=$cmd_path[0]
command_args="$cmd_argl[0]"
pidfile=$pidfile

name="$svc_name"
description="$desc"
EOF

close FH;


__END__

=head1 NAME

initify - Convert systemd units to OpenRC init-files

=head1 SYNOPSIS

    initify [options] file

=head2 Options

=over 12

=item -h, --help

Print this message

=item -n <name>, --name=<name>

Set the name of the unit created

=back

=cut