Fix write/close deadlock #50
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When the monitor goroutine sees that the connection has closed, it is sometimes possible for resetChan to be full and a Write() invocation blocked sending to resetChan. If this happens, and monitor attempts to grab the write lock, it will result in a deadlock because Write() has the lock, monitor is trying to acquire the lock, and nothing is draining resetChan. Start a goroutine in monitor to drain resetChan, just before trying to acquire the lock. Fixes moby#49 Signed-off-by: Andy Goldstein <agoldste@redhat.com>
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When the monitor goroutine sees that the connection has closed, it is
sometimes possible for resetChan to be full and a Write() invocation
blocked sending to resetChan. If this happens, and monitor attempts to
grab the write lock, it will result in a deadlock because Write() has
the lock, monitor is trying to acquire the lock, and nothing is draining
resetChan.
Start a goroutine in monitor to drain resetChan, just before trying to
acquire the lock.
Fixes #49
Signed-off-by: Andy Goldstein agoldste@redhat.com