Bug 35004 - Filename returned by LocalEndpoint of UnixListener has null characters appended to the end which causes the socket file to not be deleted when the UnixListener is disposed
Summary: Filename returned by LocalEndpoint of UnixListener has null characters append...
Alias: None
Product: Class Libraries
Classification: Mono
Component: Mono.POSIX ()
Version: 4.2.0 (C6)
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-10-16 22:22 UTC by David Lechner
Modified: 2016-03-02 16:14 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description David Lechner 2015-10-16 22:22:17 UTC
Here is an NUnit test case:

using System;
using System.IO;

using NUnit.Framework;
using Mono.Unix;

namespace UnixListenerBug
  public class Test
    public void TestCase ()
      var socketFile = Path.GetFullPath ("test.socket");
      if (File.Exists (socketFile)) {
        File.Delete (socketFile);
      Assume.That (!File.Exists (socketFile));
      var listener = new UnixListener (socketFile);
      Assert.That (File.Exists (socketFile));

      // change to false to see that dispose does not delete file
      if (true) {
        listener.Start ();
        listener.Stop ();
        var filenameUsedInDisposeMethod = ((UnixEndPoint)listener.LocalEndpoint).Filename;
        Assert.That (filenameUsedInDisposeMethod, Is.EqualTo (socketFile));

      listener.Dispose ();
      Assert.That (!File.Exists (socketFile));

More info:

Rather than saving the UnixEndpoint that was passed to UnixListener.Init() [1], it saves the one that is created by the Socket[2]. The get accessor of LocalEndPont here calls UnixEndPoint.Create() [3], which is where it seems the null characters are coming from.

[1]: https://github.com/mono/mono/blob/master/mcs/class/Mono.Posix/Mono.Unix/UnixEndPoint.cs#L65
[2]: https://github.com/mono/mono/blob/master/mcs/class/Mono.Posix/Mono.Unix/UnixListener.cs#L61
[3]: https://github.com/mono/mono/blob/master/mcs/class/Mono.Posix/Mono.Unix/UnixEndPoint.cs#L65


=== MonoDevelop ===

Version 5.10
Installation UUID: f9085896-ca5c-4fa8-9f13-4f18e19b076a
	Mono 4.2.1 (Stable Tue Oct  6 14:40:19 UTC 2015) (64-bit)
	GTK+ 2.24.23 (elementary theme)

=== Build Information ===

Build information unavailable

=== Operating System ===

Linux freyr 3.16.0-50-generic #67~14.04.1-Ubuntu SMP Fri Oct 2 22:07:51 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
Comment 1 David Lechner 2015-10-16 22:31:24 UTC
Made a pull request with a proposed fix: https://github.com/mono/mono/pull/2145
Comment 2 Alexander Köplinger [MSFT] 2016-03-02 16:14:43 UTC
I merged the PR, thank you!