fix(future): race-safe remote_future_dispose — sever producer under the mutex before closing the trigger (true-async/server#93)#182
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…er the shared-state mutex before closing the trigger (true-async/server#93) Disposing a remote future while its producer thread is still completing it raced: remote_future_dispose closed the cross-thread trigger and dropped the state ref without first marking the state completed or detaching target_future, so a concurrent async_future_shared_state_complete() could ring a closing handle or resolve a freed future. It now mirrors async_future_state_object_free — under the state mutex it grabs the trigger, NULLs it, sets completed=1 and clears target_future, then disposes the trigger outside the lock — so a late completion is a clean no-op. This lets an owner dispose an unresolved remote future safely (e.g. the HTTP server reaping per-worker completion futures on pool shutdown).
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Problem
remote_future_dispose()closed the shared-state's cross-thread trigger and dropped the state ref without first marking the state completed or detachingtarget_future. A producer thread completing the future at the same moment (async_future_shared_state_complete/reject) could then:uv_closed, ortarget_futurethat the owner just freed.So disposing an unresolved remote future was unsafe — only safe once it had already resolved.
Fix
Mirror
async_future_state_object_free(): under the shared-state mutex, grab the trigger, NULL it, setcompleted = 1and cleartarget_future, then dispose the trigger outside the lock. A concurrentcomplete()/reject()(both gated oncompletedunder the same mutex) becomes a clean no-op.This lets an owner dispose an unresolved remote future safely — e.g.
HttpServerreaping the per-worker completion futures returned bysubmit_internal()on pool shutdown (true-async/server#93), which otherwise left their triggers armed on the parent reactor (loop-alive assert on debug / leaked libuv handle on release).Test
Covered end-to-end by the server suite (graceful_shutdown + reload → shutdown); no ABI change.