Preserve meaningful last_error in LibevConnection close paths#700
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dkropachev wants to merge 1 commit intomasterfrom
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Preserve meaningful last_error in LibevConnection close paths#700dkropachev wants to merge 1 commit intomasterfrom
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LibevConnection.close() closes the socket immediately while watchers are stopped asynchronously in the next event loop iteration via _loop_will_run(). This creates a race window where handle_read() or handle_write() can operate on a closed socket fd, producing EBADF errors that surface as ConnectionShutdown. - Add is_closed/is_defunct guards in handle_read() and handle_write() error paths to silently exit during shutdown instead of calling defunct() with EBADF - Set last_error in close() when connected_event is not yet set to prevent factory() from returning a dead connection - Set last_error on server-initiated close (EOF) in handle_read() before calling close()
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Lorak-mmk
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| self.last_error = ConnectionShutdown( | ||
| "Connection to %s was closed by server" % self.endpoint) | ||
| self.close() |
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Why do you set it unconditionally here, but guard it with if not self.connected_event.is_set(): in the other place?
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Summary
Improves error reporting in LibevConnection so that users see a clear
ConnectionShutdownmessage instead of a confusing[Errno 9] Bad file descriptorwhen connections close during node restarts.The libev reactor was already safe from the EBADF race —
defunct()returns early whenis_closedis true, and the single-threaded event loop +_loop_will_run()design prevents watchers from firing on closed fds. The actual problem was thatlast_errorwasn't set to a meaningful value in two close paths, so the stale EBADF string leaked up tofactory()and confused users.Changes
last_errorinclose()whenconnected_eventis not yet set, sofactory()reportsConnectionShutdowninstead of whatever stale error was on the connectionlast_erroron server-initiated close (EOF) inhandle_read()before callingclose()Test plan
tests/unit/io/test_libevreactor.pypassesRefs #614