ntpa/Ntp.Analyzer.Cli/Main.cs

//
// Main.cs
//
// Author:
//       Carsten Sonne Larsen <cs@innolan.dk>
//
// Copyright (c) 2013 Carsten Sonne Larsen
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
using System.Runtime.InteropServices;
using Ntp.Analyzer.Process;
using System.Text;
using System;

namespace Ntp.Analyzer.Cli
{
    /// <summary>
    /// Entry point for CLI application.
    /// </summary>
    public static class MainClass
    {
        [DllImport("libc")]
        private static extern int getpid ();

        [DllImport ("libc")] // Linux
        private static extern int prctl (int option, byte[] arg2, IntPtr arg3, IntPtr arg4, IntPtr arg5);

        [DllImport ("libc")] // BSD
        private static extern void setproctitle (byte[] fmt, byte[] str_arg);

        /// <summary>
        /// This is from http://abock.org/2006/02/09/changing-process-name-in-mono/
        /// </summary>
        /// <param name="name">Name.</param>
        private static void SetPosixProcessName (string name)
        {   
            try {
                if (prctl (15 /* PR_SET_NAME */, Encoding.ASCII.GetBytes (name + "\0"), IntPtr.Zero, IntPtr.Zero, IntPtr.Zero) != 0) { 
                    throw new ApplicationException ("Error setting process name: " + Mono.Unix.Native.Stdlib.GetLastError ());
                }   
            } catch (EntryPointNotFoundException) {
                // Not every BSD has setproctitle
                try {
                    setproctitle (Encoding.ASCII.GetBytes ("%s\0"), Encoding.ASCII.GetBytes (name + "\0"));
                } catch (EntryPointNotFoundException) {
                }
            }   
        }

        /// <summary>
        /// The entry point of the program, where the program control starts and ends.
        /// </summary>
        /// <param name="args">The command-line arguments.</param>
        public static void Main (string[] args)
        {
            string configFile = (args.Length > 0) ? args [0] : "/etc/ntpa.conf";
            int pid = getpid ();

            Main main = new Main (configFile, pid);
            main.Start ();
        }
    }
}