Message is 'stuck' when the network cable is unplugged

[Nguyen Minh Giang]

Description

when I unplug the network cable. Even though rd_kafka_poll() still calls continuously, delivery report is never called when the local message timeout (30s) is reached until the network cable is reconnected.

How to reproduce

1. Produce some message with rd_kafka_producev(). Create a thread and repeatedly call rd_kafka_poll(), set message.timeout.ms = 30000.
2. Unplug the network cable (Waited more than message.timeout.ms but still did not see the delivery returned).
3. Reconnect the network cable. Delivery report function immediately returns 'local message timeout' error.

Checklist

Please provide the following information:

• librdkafka version (release number or git tag): v0.13.4