pbot/applets/compiler_vm/guest/bin/accept-vsock-client

#!/usr/bin/env perl

# File: accept-vsock-client
#
# Purpose: Accepts and handles a client connecting over Linux VM socket.

# SPDX-FileCopyrightText: 2022 Pragmatic Software <pragma78@gmail.com>
# SPDX-License-Identifier: MIT

use 5.020;

use warnings;
use strict;

use feature qw/signatures/;
no warnings qw(experimental::signatures);

use constant {
    USERNAME => 'vm',
    MOD_DIR  => '/usr/local/share/pbot-vm/',
};

use lib MOD_DIR;

use Guest;

sub accept_client() {
    print STDERR "VSOCK accepted new connection.\n";

    my $buffer = '';

    while (1) {
        my $command = Guest::read_input(*STDIN, \$buffer, 'VSOCK');

        if (not defined $command) {
            # recoverable error or waiting for more input
            next;
        }

        if (not $command) {
            # unrecoverable error or input closed
            exit 1;
        }

        last;
    }

    eval { require "Languages/$command->{lang}.pm" };

    if ($@) {
        require 'Languages/_default.pm';
        $command->{lang} = '_default';
    }

    my $mod = $command->{lang}->new(%$command);

    my $result = Guest::process_command($command, $mod, USERNAME, 'VSOCK');

    if (not defined $result) {
        $result = "[Fatal error]";
    }

    if ($result) {
        Guest::send_output(*STDOUT, $result, 'VSOCK');
        exit; # exit child process
    }
}

accept_client();