From 1934124c40c9d8e087af798c5f7722dd1f802583 Mon Sep 17 00:00:00 2001
From: PhysicistJohn <54456354+PhysicistJohn@users.noreply.github.com>
Date: Fri, 12 Jun 2026 10:01:57 -0700
Subject: [PATCH] Fix DDS init on modern kernels: idempotent
 ChannelFactory.Init + relax cyclonedds pin

Two stacked failures on Ubuntu 24.04 (kernel 6.x):

1. cyclonedds 0.10.2's Domain creation hangs indefinitely on recent
   kernels, so run_sim_loop.py dies at ChannelFactoryInitialize with no
   error. Relax the pin to >=0.10.2,<12 (the SDK works unmodified
   against cyclonedds 11.x).

2. With cyclonedds >= 11, re-creating a Domain for the same id in one
   process raises DDSException ("Occurred upon initialisation of a
   cyclonedds.domain.Domain"). run_sim_loop.py initializes the channel
   factory from both the control loop and the simulator, so the second
   Init failed the whole loop:

       ChannelFactoryInitialize(0, 'lo')   # ok
       ChannelFactoryInitialize(0, 'lo')   # raises

   ChannelFactory is already a Singleton; make Init a no-op when the
   domain is live.
---
 external_dependencies/unitree_sdk2_python/setup.py         | 2 +-
 .../unitree_sdk2_python/unitree_sdk2py/core/channel.py     | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/external_dependencies/unitree_sdk2_python/setup.py b/external_dependencies/unitree_sdk2_python/setup.py
index 54d8cac8a..ad2252e61 100644
--- a/external_dependencies/unitree_sdk2_python/setup.py
+++ b/external_dependencies/unitree_sdk2_python/setup.py
@@ -14,7 +14,7 @@
       },
       python_requires='>=3.8',
       install_requires=[
-            "cyclonedds==0.10.2",
+            "cyclonedds>=0.10.2,<12",
             "numpy",
             "opencv-python",
       ],
diff --git a/external_dependencies/unitree_sdk2_python/unitree_sdk2py/core/channel.py b/external_dependencies/unitree_sdk2_python/unitree_sdk2py/core/channel.py
index daacc6323..1f7f603d6 100644
--- a/external_dependencies/unitree_sdk2_python/unitree_sdk2py/core/channel.py
+++ b/external_dependencies/unitree_sdk2_python/unitree_sdk2py/core/channel.py
@@ -196,6 +196,13 @@ def __init__(self):
         super().__init__()
 
     def Init(self, id: int, networkInterface: str = None, qos: Qos = None):
+        # Idempotent: the factory is a Singleton, and re-creating the Domain for
+        # the same process raises on cyclonedds >= 11 ("Occurred upon
+        # initialisation of a cyclonedds.domain.Domain"). gear_sonic initializes
+        # from both the control loop and the simulator in one process, so a
+        # second Init with an already-live domain must be a no-op.
+        if self.__domain is not None:
+            return True
         config = None
         # choose config
         if networkInterface is None: