* Prevent old packets resolution.
With range map, we are just looking up ranges and not exactly
which packets were missing. This caused the case of old packets
being resolved after layer switch.
For example,
- Packet 10 is layer switch, range map gets reset
- Packet 11, 12, 13 are forwarded
- Packet 9 comes, it should ideally be dropped as pre-layer switch old
packet. But, when looking up range map, it gets an offset and hence
gets re-mapped to something before layer switch. This was probably
okay as decoders would have had a key frame at the switch point and
moved ahead, but incorrect technically.
Fix is to reset the start point in the range map to the switch point
and not 0. So, when packet 9 comes, range map will return "key too old"
error and that packet will be dropped as missing from cache.
* fix tests
* Handle duplicate padding packet in the up stream.
The following sequence would have produce incorrect results
- Sequence number 39 - regular packet - offset = 0
- Sequence number 40 - padding only - drop - offset = 1
- Sequence number 40 - padding only duplicate - was not dropped (this is
the bug) - apply offet - sequence number becomes 39 and clashes with
previous packet
- Sequence number 41 - regular packet - apply offset - goes through as 40.
- Sequence number 40 again - does not get dropped - will pass through as 39.
* fix duplicate dropping
* fix tests
* accept repeat last value as padding injection could cause that
* use exclusion ranges
* more UT and more specific errors
* Drop padding only packet on publisher side.
* add UT
* update deps
* remove debug
* add fast path short cut
* correct comment
* fix test
* fix for Linux