Program.cs

Go to the documentation of this file.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Threading;
using System.Threading.Tasks;
 
using Microsoft.Extensions.Hosting.Systemd;
using Microsoft.Extensions.Logging;
 
using Tgstation.Server.Common;
using Tgstation.Server.Common.Extensions;
using Tgstation.Server.Host.Watchdog;
 
namespace Tgstation.Server.Host.Console
{
    static class Program
    {
        internal static IWatchdogFactory WatchdogFactory { get; set; }
 
        static Program()
        {
            WatchdogFactory = new WatchdogFactory();
        }
 
        internal static async Task<int> Main(string[] args)
        {
            System.Console.Title = $"{Constants.CanonicalPackageName} Host Watchdog v{Assembly.GetExecutingAssembly().GetName().Version?.Semver()}";
 
            var arguments = new List<string>(args);
            var trace = arguments.Remove("--trace-host-watchdog");
            var debug = arguments.Remove("--debug-host-watchdog");
 
            const string SystemDArg = "--Internal:UsingSystemD=true";
            if (!arguments.Any(arg => arg.Equals(SystemDArg, StringComparison.OrdinalIgnoreCase))
                && SystemdHelpers.IsSystemdService())
                arguments.Add(SystemDArg);
 
            using var loggerFactory = LoggerFactory.Create(builder =>
            {
                if (trace)
                    builder.SetMinimumLevel(LogLevel.Trace);
                else if (debug)
                    builder.SetMinimumLevel(LogLevel.Debug);
 
                builder.AddConsole();
            });
 
            var logger = loggerFactory.CreateLogger(nameof(Program));
            try
            {
                if (trace && debug)
                {
                    logger.LogCritical("Please specify only 1 of --trace-host-watchdog or --debug-host-watchdog!");
                    return 2;
                }
 
                using var cts = new CancellationTokenSource();
                void AppDomainHandler(object? a, EventArgs b) => cts.Cancel();
                AppDomain.CurrentDomain.ProcessExit += AppDomainHandler;
                try
                {
                    System.Console.CancelKeyPress += (a, b) =>
                    {
                        b.Cancel = true;
                        cts.Cancel();
                    };
 
                    var watchdog = WatchdogFactory.CreateWatchdog(
                        RuntimeInformation.IsOSPlatform(OSPlatform.Windows)
                            ? new NoopSignalChecker()
                            : new PosixSignalChecker(
                                loggerFactory.CreateLogger<PosixSignalChecker>()),
                        loggerFactory);
 
                    return await watchdog.RunAsync(false, arguments.ToArray(), cts.Token)
                        ? 0
                        : 1;
                }
                finally
                {
                    AppDomain.CurrentDomain.ProcessExit -= AppDomainHandler;
                }
            }
            catch (Exception ex)
            {
                logger.LogCritical(ex, "Failed to run!");
                return 3;
            }
        }
    }
}