Fix Vulcan compatibility: withhold pings until JOIN_GAME is sent - #138
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devamyst wants to merge 1 commit into
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Fix Vulcan compatibility: withhold pings until JOIN_GAME is sent#138devamyst wants to merge 1 commit into
devamyst wants to merge 1 commit into
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… is sent Vulcan expects JOIN_GAME to be the first PLAY packet it sees. Grim could send a ping/transaction packet before JOIN_GAME actually went out (e.g. in the PLAYER_ABILITIES send handler during the join sequence), which Vulcan then flagged as an out-of-order confirmation packet and kicked for. GrimPlayer now tracks whether JOIN_GAME has been written to the client and sendTransaction() withholds until that's true. Fixes Axionize#127 Note: this does not replace disable-pong-cancelling. That setting must stay false (the default) for Vulcan compatibility — enabling it stops Grim from cancelling its own transaction/pong responses, so Vulcan's own listener ends up seeing IDs it didn't send and kicks for a mismatch mid-session. Server admins running Vulcan alongside Grim should leave disable-pong-cancelling: false.
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Summary
JOIN_GAMEwas actually written to the client (e.g. from thePLAYER_ABILITIESsend handler during the join sequence). Vulcan treatsJOIN_GAMEas the first PLAY packet it expects, so an early ping showed up as an out-of-order confirmation and got the player kicked.GrimPlayernow tracks whetherJOIN_GAMEhas actually been sent (hasSentJoinGamePacket), set viaevent.getTasksAfterSend()inPacketPlayerRespawn's existingJOIN_GAMEhandler, andsendTransaction()withholds until that flag is true.Important:
disable-pong-cancellingmust stayfalseThis PR does not replace the
disable-pong-cancellingconfig option, and does not require enabling it. Server admins running Vulcan alongside Grim should leavedisable-pong-cancelling: false(the default).We confirmed this directly: a separate, ongoing mid-session kick (
out-of-order packet (Received X ≠ Expected Y), unrelated to join timing) was traced todisable-pong-cancellingbeing set totrueon a test server — a workaround suggested elsewhere in #127 that turned out to make things worse. With ittrue, Grim stops cancelling its own transaction/pong responses, so Vulcan's own listener sees confirmation IDs it never sent and kicks for the mismatch. Setting it back tofalse(defaultLOWEST-priority cancellation inPacketPingListener) resolved that kick. Both fixes (this PR + correct config) were needed together to fully resolve Vulcan compatibility in our testing.Test plan
./gradlew build)disable-pong-cancelling: false