Introduce a new header `gil.h` defining `MutexLockIfGilDisabled` to support thread-safety in both standard and free-threaded CPython builds.
Protect critical shared states and registries:
- Guard global Python callback pointers in `callbacks.cc` using a mutex. Move `gil_scoped_acquire` into local blocks around refcount modifications to prevent `longjmp` from bypassing destructors.
- Protect raw pointer maps in `structs_wrappers.cc` with static mutexes.
- Replace TOCTOU race in `mjcb_time` initialization with thread-safe `std::call_once`.
- Add synchronization to lazy indexer array cache initialization in `indexers.cc` and `indexer_xmacro.h`.
- Protect vector mutations in `StructListBase::PopulateUpTo` in `structs.h` with a mutex.
- Revert unnecessary atomic changes to threadpool counters.
- Declare free-threading compatibility by passing `pybind11::mod_gil_not_used()` to all extension modules.
Fixes#3259Fixes#3256Fixes#2978
PiperOrigin-RevId: 941101502
Change-Id: Iec4ce58afcbc75d4b0be6a9a21fc8a47854242e3
Before this change, MjDataWrapper contained a custom data structure called MjDataMetadata, which contained the sizes of various arrays needed to create MjData. This was used for serialization and deserialization, as well as copying MjData instances.
This worked fine for native MuJoCo models, but as soon as plugins were used, there was information in the model that was needed and not available in MjDataMetadata. Since plugins are so general, keeping MjDataMetadata was untenable.
PiperOrigin-RevId: 578205355
Change-Id: I11b9ee797d1da5aaf1fecbbe170b3b0f1f1a3e6c
List all valid names in the error message.
Fix an off-by-one error when accessing elements by numeric index (rather than name).
PiperOrigin-RevId: 457702283
Change-Id: I6e4f1518b4ecd9ca91ac9b0bf6b0963fc0a9bd18
Saran Tunyasuvunakool