Kavita/Kavita.Common/EnvironmentInfo/IOsInfo.cs

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;

namespace Kavita.Common.EnvironmentInfo;

public class OsInfo : IOsInfo
{
    public static Os Os { get; }

    public static bool IsNotWindows => !IsWindows;
    public static bool IsLinux => Os is Os.Linux or Os.LinuxMusl or Os.Bsd;
    public static bool IsOsx => Os == Os.Osx;
    public static bool IsWindows => Os == Os.Windows;

    // this needs to not be static so we can mock it
    public bool IsDocker { get; }

    public string Version { get; }
    public string Name { get; }
    public string FullName { get; }

    static OsInfo()
    {
        var platform = Environment.OSVersion.Platform;

        switch (platform)
        {
            case PlatformID.Win32NT:
            {
                Os = Os.Windows;
                break;
            }

            case PlatformID.MacOSX:
            case PlatformID.Unix:
            {
                Os = GetPosixFlavour();
                break;
            }
        }

    }

    public OsInfo(IEnumerable<IOsVersionAdapter> versionAdapters)
    {
        OsVersionModel osInfo = null;

        foreach (var osVersionAdapter in versionAdapters.Where(c => c.Enabled))
        {
            try
            {
                osInfo = osVersionAdapter.Read();
            }
            catch (Exception e)
            {
                Console.WriteLine("Couldn't get OS Version info: " + e.Message);
            }

            if (osInfo != null)
            {
                break;
            }
        }

        if (osInfo != null)
        {
            Name = osInfo.Name;
            Version = osInfo.Version;
            FullName = osInfo.FullName;
        }
        else
        {
            Name = Os.ToString();
            FullName = Name;
        }

        if (IsLinux && File.Exists("/proc/1/cgroup") && File.ReadAllText("/proc/1/cgroup").Contains("/docker/"))
        {
            IsDocker = true;
        }
    }

    public OsInfo()
    {
        Name = Os.ToString();
        FullName = Name;

        if (IsLinux && File.Exists("/proc/1/cgroup") && File.ReadAllText("/proc/1/cgroup").Contains("/docker/"))
        {
            IsDocker = true;
        }
    }

    private static Os GetPosixFlavour()
    {
        var output = RunAndCapture("uname", "-s");

        if (output.StartsWith("Darwin"))
        {
            return Os.Osx;
        }
        else if (output.Contains("BSD"))
        {
            return Os.Bsd;
        }
        else
        {
#if ISMUSL
                return Os.LinuxMusl;
#else
            return Os.Linux;
#endif
        }
    }

    private static string RunAndCapture(string filename, string args)
    {
        var p = new Process
        {
            StartInfo =
            {
                FileName = filename,
                Arguments = args,
                UseShellExecute = false,
                CreateNoWindow = true,
                RedirectStandardOutput = true
            }
        };

        p.Start();

        // To avoid deadlocks, always read the output stream first and then wait.
        var output = p.StandardOutput.ReadToEnd();
        p.WaitForExit(1000);

        return output;
    }
}

public interface IOsInfo
{
    string Version { get; }
    string Name { get; }
    string FullName { get; }

    bool IsDocker { get; }
}

public enum Os
{
    Windows,
    Linux,
    Osx,
    LinuxMusl,
    Bsd
}