Handle Invalid

[benaadams]

A handle is getting lost somewhere and either finalised or early disposed; it most often shows up on mono and randomly causes tests to fail; mostly tarvis in but occasionally also happens on appveyor.

Haven't be able to track down the cause

e.g. #335 with the following resilts: https://travis-ci.org/aspnet/KestrelHttpServer/builds/89566455

info: workingdir: test/Microsoft.AspNet.Server.Kestrel.FunctionalTests
Discovering: Microsoft.AspNet.Server.Kestrel.FunctionalTests
Discovered: Microsoft.AspNet.Server.Kestrel.FunctionalTests
Starting: Microsoft.AspNet.Server.Kestrel.FunctionalTests
Stacktrace:
Native stacktrace:
mono() [0x4b23dc]
mono() [0x508a0e]
mono() [0x428fad]
/lib/x86_64-linux-gnu/libpthread.so.0(+0xfcb0) [0x7fd272101cb0]
/home/travis/libuvinstall/lib/libuv.so(uv_async_send+0x4) [0x7fd25eae0844]
[0x40e97908]
Debug info from gdb:

Got a SIGSEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.

If I submit again it will likely pass the test.

[benaadams]

hmm uv_async_send would be loop disposable; maybe just needs a handle.Validate

[benaadams]

If I add this Assert in I get two asserts running the tests

public void async_send(UvAsyncHandle handle)
{
    // Can't Assert with .Validate as that checks threadId
    // and this function is to post to correct thread.
    Debug.Assert(!handle.IsInvalid, "Handle is invalid");
    Check(_uv_async_send(handle));
}

Checking to see if its tests that are wrong rather than a race condition

[benaadams]

Seems to mostly happen when posting close to a closed socket

[benaadams]

Does happen on Windows occasionally also:

Unhandled Exception: System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
at Microsoft.AspNet.Server.Kestrel.Networking.Libuv.NativeMethods.uv_async_send(UvAsyncHandle handle)
at Microsoft.AspNet.Server.Kestrel.Networking.Libuv.async_send(UvAsyncHandle handle)
at Microsoft.AspNet.Server.Kestrel.Networking.UvAsyncHandle.Send()
at Microsoft.AspNet.Server.Kestrel.KestrelThread.Post[T](Action1 callback, T state) at Microsoft.AspNet.Server.Kestrel.Http.SocketOutput.ScheduleWrite() at Microsoft.AspNet.Server.Kestrel.Http.SocketOutput.Write(ArraySegment1 buffer, Action`3 callback, Object state, Boolean immediate, Boolean socketShutdownSend, Boolean socketDisconnect)
at Microsoft.AspNet.Server.Kestrel.Http.SocketOutput.End(ProduceEndType endType)
at Microsoft.AspNet.Server.Kestrel.Http.Connection.Microsoft.AspNet.Server.Kestrel.Http.IConnectionControl.End(ProduceEndType endType)
at Microsoft.AspNet.Server.Kestrel.Http.Frame.d__82.MoveNext()