Server.handleCalls: deal with ack/Go correctly when shutting down. #428
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Previously, the logic to check for an ack after returning from handleCall was missing from the loop that drains the queue after the server's context is canceled. This means that if when draining the queue, if a method handle calls .Go() before checking the context, there will be two goroutines servicing method calls when it returns. This patch folds the shutdown into the same loop, so that the logic is the same, and so that the shutdown logic respects acks. Since the queue is meant to be single-consumer, the exact consequences of this are a bit hard to reason about, though I have noticed that after fixing this some of the behavior I had attributed to capnproto#423 is less common.
lthibault
approved these changes
Jan 14, 2023
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Previously, the logic to check for an ack after returning from handleCall was missing from the loop that drains the queue after the server's context is canceled. This means that if when draining the queue, if a method handle calls .Go() before checking the context, there will be two goroutines servicing method calls when it returns.
This patch folds the shutdown into the same loop, so that the logic is the same, and so that the shutdown logic respects acks.
Since the queue is meant to be single-consumer, the exact consequences of this are a bit hard to reason about, though I have noticed that after fixing this some of the behavior I had attributed to #423 is less common.