* fix(xnet): install a retransmission timer on TCP connections
No connection created through x/xnet had one. Neither NewTCPPool nor the
dial path in StackGo set ConnConfig.LossRecovery and ConnConfig.Nanotime,
so tcp.Handler ran with loss recovery disabled: nothing noticed a lost
segment, and the connection simply stopped: the sender waiting for an
ACK that cannot arrive, the receiver for data nobody will resend.
TCPPoolConfig.NanoTime already documents itself as "passed to each
tcp.Conn for retransmission timing (RFC 6298)", including the
time.Now fallback when it is nil; this makes that true. Each connection
gets its own tcp.RTO, which shadows that connection's send sequence space
and so cannot be shared. That is 80 bytes per connection, allocated once
at pool construction, against buffers measured in kilobytes.
The test drops exactly one data segment and requires the byte to arrive
anyway. It depends on the FIN-WAIT-1 retransmission fix, since the server
closes after writing.
* merge main fixes
* claude: fix up test to use ltesto.Sched and enable ltesto.Sched multigoro
* move test and simplify top comment
---------
Co-authored-by: Derek den Haas <i.pestano@easyflor.nl>
* use ltesto as package to contain scheduler/goroutine testing logic
* add sched usage to another test
* testCloseTransmitsPending rewrite
* replace deadline with context
* begin adding better fuzz test
* finish adding working fuzzer
* implement mutateipv4
* fuzzer finds a panic in ICMP client on receive empty payload
* rename fuzz tests to reflect fuzz methodology
* reduce heap allocations in tcp logging; omit use of AppendFloat which allocates a metric sh*tton
* debugheaplog: better heap statistic logging
* heap: use string for pcap.Frame.Protocol
* add potential to eliminate Flags.String heap alloc, remove incorrect HEAP comments
* add StackAsync.DebugErr and httpraw.SetBytes
* many heap alloc reductions and replacement of bytes.Equal with internal.BytesEqual
* claude suggests a way forward
* add timing to capture printer
* add pcap.Flags
* fix ICMP CRC calculation and add test
* bugfix: still send data on half-close state(close-wait)
* fix pcap test
* Simplified checksum calculation and verification
* Fixed tests
* UDP: using NewBoundedFrame to create a Frame instance limited to the actual frame size.
* Minor: renamed some functions
* Commented and made more readable consecutive SetCRC calls.
* Fixed icmp checksum calculation after rebase
* Replaced NewBoundedFrame with explicit validation
* add prints to investigate slowness
* add loop sleep for blocking Stack
* add connection close http attribute and detect end of HTML page
* add timeout to bridge read
* examples/xnet: add ntp timestamp to prints and show output in readme
* add polling to http tap interface
* more digits in ntp format
* prevent crashes on non-8 timestamp
Pat Whittingslow
Marvin Drees
ddirect