CydandClaude Fable 5
b01db52d43
Twenty-two Fail sites in L4NET.CPP -- the whole console/mesh transport -- replaced with decomp-verified bodies (part_007.c @004501d4..@00452378), every error string extracted byte-for-byte from the shipped exe, every magic number resolved to a macro from the AUTHENTIC 1995 NETNUB.HPP that survives in the archive (NETCOM_VERSION 11; 0x63c == MAX_SEND_DATA_SIZE). The real-mode bridge came free: the 1995 netshare.OBJ has been linking into mungal4.lib all along via the prebuilt fallback -- this file only had to define the six globals it imports and call it. NetNub::SendCommand is the gateway (setRMBuff, DPMI int 31h/0300h on the TSR's vector, getRMBuff); BC4.52's <dos.h> really has int386x -- the binary's own "int386x():ERROR=" text named the RTL call. The topology, decomp-proven: console listens on 1501, the pod mesh on 1502; hosts before ours in the egg get an OPEN, ours becomes the local host by address match, hosts after ours get a LISTEN -- and CheckBuffers heals the ordering race by SWAPPING sockets when a peer lands on the wrong listen. The console's listen is a wildcard that learns its address; the console connection SURVIVES mission teardown (Shutdown zeroes both counters anyway -- reproduced faithfully). Send discipline: direct while the retry buffer is empty, everything queues behind a backlog in per-host FIFO, one round-robin drain per idle slot; only a dumped-to-avoid-blocking send is retried, and RemovePacket is empty in the binary because delivery already compacted the pad buffer. Internal connect/disconnect events ride the GetNetworkClientPointer(0)->ReceiveNetworkPacket self-dispatch (the decomp's FUN_0041d7f0 resolves to the ClientID-0-is-me idiom). Ghidra had dropped register and trailing arguments at half a dozen call sites (GetRemoteHost's HostID among them) -- the surviving HPP signatures arbitrated each. Stubs: 8 across 8 files -- ALL RUNTIME STUBS ARE NOW CLEAR; what remains is the authoring-side CreateStreamedSubsystem family, which missions never call. Single-user regression clean on the rig; the networked path awaits its console + NetNub-TSR live session (two-agreeing-runs). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
88 lines
5.0 KiB
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88 lines
5.0 KiB
Markdown
# L4NET.CPP — the NetNub networked layer (reconstructed 2026-08-04, 5.3.117)
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The pod's entire console/mesh transport: the protected-mode client of the
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real-mode NetNub TSR. Every body verified against the shipped binary
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(part_007.c cluster @004501d4..@00452378); every error string extracted
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byte-for-byte from BTL4OPT.EXE; the authentic interface header
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(CODE/RP/MUNGA_L4/NetNub/NETNUB.HPP, NETCOM_VERSION 11) supplied every
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struct and function code, and each binary literal resolved to one of its
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macros (0x63c == MAX_SEND_DATA_SIZE, 0x2c == MULTIPLE_SEND_BUFFER_SIZE(0),
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0x640 == MAX_RECEIVE_DATA_SIZE, 10 == the frame's destination limit).
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## The real-mode bridge
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`NetNub::SendCommand` (@00452100) is the gateway: `setRMBuff()` pushes the
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PM Netcom's Function/Status/Buffer_Length + buffer down to the real-mode
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shared block, DPMI int 31h/0300h fires the TSR's interrupt (vector from
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`getRMNumbers()`), `getRMBuff()` pulls the reply back. The bridge routines
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are NOT recompiled — the SURVIVING 1995 `netshare.OBJ`
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(CODE/RP/MUNGA_L4) has been a mungal4.lib member all along via the
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prebuilt-fallback (`netshare` in ORDER_mungal4); this file only had to
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supply the C-side globals it imports (`Function_Ptr`, `Buffer_Length_Ptr`,
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`baseadr:offs`, `RMFunction_Off`, `RMBuffer_Length_Off` — binary homes
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0x522b84..0x522b98) and `extern "C"` prototypes (TASM uppercased the OBJ's
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symbols; tlink32 matches caselessly — no `/c`). BC4.52's 32-bit <dos.h>
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really does have `int386x`/`segread` — the binary's own error text
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("int386x():ERROR=") named the RTL call. The register image zeroes exactly
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the fields the binary zeroes (reserved/flags/fs/gs/ss:sp).
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## The topology (all decomp-proven)
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- Console listens on TCP **1501**, pod mesh on TCP **1502**.
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- `StartConnecting`: hosts BEFORE ours in the egg list get an active OPEN
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(they already listen); our entry is recognized by address and adopted as
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the local host; hosts AFTER ours get a LISTEN. That ordering rule forms
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the peer-to-peer mesh without collisions. A slave then Sends
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AcknowledgeEggFile to the console; MasterMode Fails ("host is in an
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illegal startup mode" — 4.10 pods are always slaves).
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- `CheckBuffers` (@004518b8) is the pump: deliver a whole buffered packet;
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else advance ONE connection state machine per call (OPEN must match its
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address — Verify; the console LISTEN is a wildcard that learns its
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address; a mesh peer landing on the WRONG listen gets its socket SWAPPED
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to the record that expects it — the race healer), then one
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MULTIPLE_RECEIVE drains the wire into per-host pad buffers
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(pad_size/pad_head/pad_tail — the surviving L4HOST.HPP names them).
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- Wire frame = `NetworkPacketHeader{clientID, gameID, fromHost, timeStamp}`
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+ message; the netnub strips the leading socket handle.
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`GetNextMungaPacket` round-robins hosts from `lastHostIteratorPosition`,
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copies out one whole packet, memmove-compacts the pad. `RemovePacket`
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is EMPTY in the binary (@004520f8) — delivery already dequeued.
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- Send discipline: buffer empty → direct send, and only a
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NETNUB_DATA_DUMPED (would-block) result queues the message; buffer
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non-empty → everything queues BEHIND (per-host FIFO) + one drain attempt.
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`ExecuteBackground` drains one request per idle slot. The MessageBuffer
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copies each message (SendRequest owns the copy), tables queues by host,
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and round-robins them. A disconnect during send posts the internal
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HostDisconnected event through `GetNetworkClientPointer(0)->
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ReceiveNetworkPacket(NULL, &msg)` — the self-dispatch idiom the decomp's
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`FUN_0041d7f0(this,0)` resolves to (ClientID 0 == the manager).
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- `Shutdown`: game hosts close + destroy; THE CONSOLE CONNECTION SURVIVES
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the mission (pod returns to the console-only lobby). The binary zeroes
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BOTH connection counters even though the console stays online —
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reproduced faithfully (the console's own disconnect path recreates its
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listener rather than decrementing through zero).
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- `Mode`: reliable == the netnub BLOCKS in send (SET_SWITCHES
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blocking_switch=1); unreliable == non-blocking, dumps join the retry
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buffer. The ctor forces ReliableMode; the engine flips to Unreliable
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during map load.
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## Sources & drift notes
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- RP411's L4NET.CPP is the 2007 WinSock port — its 1995 NetNub code
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survives only in comment blocks (used line-for-line for the ctor RM
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plumbing). CODE/RP's L4NET.HPP + NETNUB.HPP + NETSHARE.ASM are
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authentic-form.
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- Ghidra dropped register/trailing args at several sites
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(GetRemoteHost's HostID, SendMessageToNetnub's host argument,
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CreateWeaponExplosions-style stack args) — the HPP signatures and
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HostManager's Find-based GetRemoteHost settle each.
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## Runtime status
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Single-user path regression-clean on the rig (mission soak, no faults).
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The NETWORKED path compiles + links (0 unresolved) but awaits its live
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test: a console + NetNub-TSR session (net_loop-style conf) driving OUR
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BTL4REC — the console handshake (egg → Ack → connections → LoadMission),
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a two-pod mesh, and mission teardown back to the lobby. Two-agreeing-runs
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rule applies.
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