Use RLock instead of Lock to prevent thread deadlock#1008
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Kludex
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| class ThreadLock: | ||
| class ThreadRLock: |
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Do we need to rename the classes tho?
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No, that was only to make it more explicit. I've updated the PR now to make the change more minimal ;-)
A thread that already holds `_optional_thread_lock` can re-enter it in nested call paths. `threading.Lock` deadlocks on a second acquire from the same thread; `threading.RLock` allows re-entrant acquisition. Ported from encode/httpcore#1003 (Zenulous), via codeberg.org/httpxyz/httpcorexyz@3058e2d. Co-Authored-By: Zenulous <zen@zenulous.com>
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Summary
A thread that already holds
_optional_thread_lockon(Async)ConnectionPoolcan re-enter the lock in nested call paths.threading.Lockdeadlocks on a second acquire from the same thread;threading.RLockallows re-entrant acquisition and resolves the hang.This PR:
threading.Lock()forthreading.RLock()in the sync variant. The async variant remains a no-op.- RenamesThreadLock→ThreadRLockandAsyncThreadLock→AsyncThreadRLockinhttpcore2/_synchronization.pyto make the lock semantics explicit. The names are private (module is_synchronization), so this is not a public API change.- Updates the two import / usage sites in_async/connection_pool.pyand_sync/connection_pool.py.Ported from encode/httpcore#1003 (Zenulous), via codeberg.org/httpxyz/httpcorexyz@3058e2d.
Note: this change was prepared with AI assistance (Claude Code).