NFD » ndn-cxx

1) Segment fetcher sends an interest with Nonce=1
2) After 1 second, segment fetcher sends another interest with same name with Nonce=2
3) Face gets data, satisfies interest with Nonce=1
4) Segment fetcher informs NLSR of the new data
5) Segment fetcher removes corresponding entry from from pending interest map
6) Face satisfies interest with Nonce=2
7) Segment fetcher hangs while trying to re-erase the entry already erased in 5) by using an invalid iterator (here)

See attached folder for reproduction on a small scale. Logs from consumer:

1541784024.347425 DEBUG: [ndn.Face] <I /example/testApp?ndn.MustBeFresh=true&ndn.Nonce=2593228152
1541784025.347404 DEBUG: [ndn.Face] <I /example/testApp?ndn.MustBeFresh=true&ndn.Nonce=1097587936
1541784025.350393 DEBUG: [ndn.Face] >D /example/testApp/%00%00
1541784025.350405 DEBUG: [ndn.Face]    satisfying /example/testApp?ndn.MustBeFresh=true&ndn.Nonce=2593228152 from app
1541784025.350436 DEBUG: [ndn.security.v2.Validator] > Start validating data /example/testApp/%00%00
1541784025.350441 TRACE: [ndn.security.v2.ValidationState] > Signature verification bypassed for data `/example/testApp/%00%00`
Got data
1541784025.350508 TRACE: [ndn.security.v2.ValidationState] ~ValidationState
1541784025.350520 DEBUG: [ndn.Face]    satisfying /example/testApp?ndn.MustBeFresh=true&ndn.Nonce=1097587936 from app
1541784025.350530 DEBUG: [ndn.security.v2.Validator] > Start validating data /example/testApp/%00%00
1541784025.350533 TRACE: [ndn.security.v2.ValidationState] > Signature verification bypassed for data `/example/testApp/%00%00
Hangs with 100% CPU usage.

This behaviour is not observed in latest ndn-cxx fetcher as the fetcher destroys itself after informing the application about the data on step 4 (see note1).

Workaround is to set useConstantInterestTimeout to true so that segment fetcher will not send interests before actual timeout.