#!/usr/local/cpanel/3rdparty/bin/perl

# cpanel - scripts/verify_pidfile                  Copyright 2022 cPanel, L.L.C.
#                                                           All rights reserved.
# copyright@cpanel.net                                         http://cpanel.net
# This code is subject to the cPanel license. Unauthorized copying is prohibited

use strict;
use Cpanel::SafeFile ();
use Cpanel::Services ();
use IO::Handle       ();

my ( $user, $service, $pidfile, $regex ) = @ARGV;

if ( !length $user || !length $service || !length $pidfile ) {
    usage();
    exit 1;
}

my %args = (
    'user'    => $user,
    'service' => $service,
);
if ( length $regex ) {
    $args{'regex'} = $regex;
}

my $time_boundary = time;
my $ps_info_for   = Cpanel::Services::get_running_process_info(%args);

if ( !exists $ps_info_for->{$service} ) {
    print STDERR "$service does not appear to be running as user $user\n";
    if ( $time_boundary > ( stat $pidfile )[9] ) {
        remove_pidfile($pidfile) if -e $pidfile;
    }
    exit 2;
}

if ( -e $pidfile ) {
    my $pid = read_pidfile($pidfile);

    if ( $ps_info_for->{$service}{'pid'} ne $pid ) {
        print STDERR "Pidfile for $service does not appear to match running pid $pid\n";
        exit 3;
    }
}
else {
    print STDERR "$service is running but pidfile is missing\n";
    exit 4;
}

exit 0;

sub usage {
    print "Usage: $0 USER SERVICE PIDFILE [REGEX]\n";
}

sub remove_pidfile {
    my ($pidfile) = @_;
    system 'rm', '-f', $pidfile;
}

sub read_pidfile {
    my ($pidfile) = @_;
    my $fh        = IO::Handle->new();
    my $lock      = Cpanel::SafeFile::safeopen( $fh, '<', $pidfile );
    if ( !$lock ) {
        print STDERR 'Unable to open pid file for reading: ' . $pidfile;
        exit 1;
    }
    my $pid = do { local $/; <$fh> };
    if ( !Cpanel::SafeFile::safeclose( $fh, $lock ) ) {
        print STDERR 'Safeclose of pid file failed: ' . $pidfile;
        exit 1;
    }
    chomp $pid;
    return $pid;
}