C# bindings - IPConnection crash in latest package version

[cristianbercu]

Issue

Cannot access a disposed object.
Object name: 'System.Net.Sockets.NetworkStream'.

Description

I have upgraded the C# bindings in my project a while ago to the latest version released on 08-Apr-2024. After update a small part of my clients reported the inability to use my product due to sudden loss of connection after a few seconds of uptime.

After doing some digging, I noticed this problem is not present in the previous binding I used 2.1.24.0.

Is this the same issue described in #57?

[photron]

As it seems to be okay for you in version 2.1.24, I don't think its the problem described in #57, I think that problem would also affect 2.1.24.

Could you narrow it down more which version exactly between 2.1.24 and 2.1.33 introduced the issue for you?

Could you get a full backtrace of the exception?

[cristianbercu]

Thanks for looking at this @photron.

I am unable to reproduce this issue on the machines I have at my disposal. This happens only in two PCs of two different clients and as a result I'm afraid I am unable to pinpoint the version that introduced the issue. It would require to build our app with all versions in between and ask our clients to try out all of them.

However, I do have the full stack trace I can share:

Mono path[0] = 'C:/Users/<Edited>/Downloads/Connection+Exam+0.5.0/Connection Exam_Data/Managed'
Mono config path = 'C:/Users/<Edited>/Downloads/Connection+Exam+0.5.0/MonoBleedingEdge/etc'
Input System module state changed to: Initialized.
[Physics::Module] Initialized fallback backend.
[Physics::Module] Id: 0xdecafbad
Initialize engine version: 6000.2.6f2 (4a4dcaec6541)
[Subsystems] Discovering subsystems at path C:/Users/<Edited>/Downloads/Connection+Exam+0.5.0/Connection Exam_Data/UnitySubsystems
GfxDevice: creating device client; kGfxThreadingModeSplitJobs
d3d12: failed to query info queue interface (0x80004002).
Direct3D:
    Version:         Direct3D 12 [level 12.1]
    Renderer:        NVIDIA GeForce RTX 3080 (ID=0x2206)
    Vendor:          NVIDIA
    VRAM:            10053 MB
    App VRAM Budget: 9285 MB
    Driver:          32.0.15.7680
Begin MonoManager ReloadAssembly
- Loaded All Assemblies, in  2.176 seconds
- Finished resetting the current domain, in  0.002 seconds
[Physics::Module] Selected backend.
[Physics::Module] Name: PhysX
[Physics::Module] Id: 0xf2b8ea05
[Physics::Module] SDK Version: 4.1.2
[Physics::Module] Integration Version: 1.0.0
[Physics::Module] Threading Mode: Multi-Threaded
<RI> Initializing input.

Using Windows.Gaming.Input
XInput1_3.dll not found. Trying XInput9_1_0.dll instead...
<RI> Input initialized.

UnloadTime: 0.528100 ms
RenderGraph is now enabled.
Config loaded successfully: 192.168.0.101, 4223, <Edited>
SocketException: A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using a sendto call) no address was supplied.
  at System.Net.Sockets.Socket.Shutdown (System.Net.Sockets.SocketShutdown how) [0x00018] in <90e034ff2da2459d9a64565cf654066d>:0 
  at Tinkerforge.SocketWrapper.Close () [0x0000b] in <35cbfd56c13d41a992405f7d5450614c>:0 
  at Tinkerforge.IPConnection.DispatchMeta (Tinkerforge.IPConnection+CallbackQueueObject cqo) [0x00074] in <35cbfd56c13d41a992405f7d5450614c>:0 
  at Tinkerforge.IPConnection.CallbackLoop (Tinkerforge.IPConnection+CallbackContext localCallback) [0x0002f] in <35cbfd56c13d41a992405f7d5450614c>:0 
  at Tinkerforge.IPConnection.<ConnectUnlocked>b__72_0 () [0x00000] in <35cbfd56c13d41a992405f7d5450614c>:0 
  at System.Threading.ThreadHelper.ThreadStart_Context (System.Object state) [0x00014] in <59bd7c40c082431db25e1e728ab62789>:0 
  at System.Threading.ExecutionContext.RunInternal (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00071] in <59bd7c40c082431db25e1e728ab62789>:0 
  at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state, System.Boolean preserveSyncCtx) [0x00000] in <59bd7c40c082431db25e1e728ab62789>:0 
  at System.Threading.ExecutionContext.Run (System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, System.Object state) [0x0002b] in <59bd7c40c082431db25e1e728ab62789>:0 
  at System.Threading.ThreadHelper.ThreadStart () [0x00008] in <59bd7c40c082431db25e1e728ab62789>:0 
UnityEngine.DebugLogHandler:Internal_LogException_Injected(Exception, IntPtr)
UnityEngine.DebugLogHandler:Internal_LogException(Exception, Object)
UnityEngine.DebugLogHandler:LogException(Exception, Object)
UnityEngine.Logger:LogException(Exception, Object)
UnityEngine.Debug:LogException(Exception)
UnityEngine.<>c:<RegisterUECatcher>b__0_0(Object, UnhandledExceptionEventArgs)

Diagnostics report saved to: C:/Users/<Edited>/AppData/LocalLow/<Edited>/Connection Exam/report.txt

There is no specific logic in our code triggering this. After a shortwhile, the IPConnection object gets disposed.

Between the version we reverted to and the latest version there is no new feature necessary for our Tinkerforge stack so the issue is non-blocking. However, if there was any optimizations done in the other areas we would love to stay up-to-date.

Let me know if there is any other information you need.