gbos.git/c/sock.h, branch master

refactor: c/ -> usr/, compiled program blobs out of the source tree

2026-07-17T22:38:38Z

Userland sources live in usr/ (fits the Unix theme better than 'c'). SDCC output .bin blobs land in build/usr/ with the other build artifacts instead of littering the source dir; programs.asm INCBINs them from there. Byte-identical ROM.

net: unbreak ping against hosts that intermittently drop ICMP

2026-07-17T17:45:13Z

Pinging sl0p.foo through gbhub looked hung: DNS resolved, then nothing. Packet-tracing showed the echo request leaving the hub's TUN and eth0 correctly NATed every time - but 80.78.19.56 blackholes ICMP for all ids in windows of tens of seconds (provider rate limiting). One lost reply wedged ping for minutes because net_recv's pump-counted timeout is effectively unbounded at native emulation speed. Two fixes: - NET_RECVNB (op 8): non-blocking recv - one RX pump, $FE if nothing buffered, same delivery/EOF semantics as NET_RECV otherwise. ping now waits <=~2s per seq (net_recv_nb + msleep loop), prints 'seq=N timeout' and moves on, like real ping. - ICMP echo id was hardcoded $1234 for every GB, every boot, so all sessions produced byte-identical flows - hostile to NAT conntrack (keyed on icmp id). wNetEchoId is now our host octet + rDIV timing noise sampled at DHCP lease, distinct per GB and per boot. Verified: 8 back-to-back native-speed gbhub runs, zero hangs; a run that hit a blackhole window printed seq=1 timeout then recovered to 3/4 received. GB<->GB ping and DNS/DHCP unaffected.

net: DHCP client - lease the IP at boot instead of hardcoding it

2026-07-17T12:11:22Z

The address is no longer baked in. net_init starts at 0.0.0.0; a DHCP client runs as the first thing on boot (init/shell forks it and waits), and only once it has a lease (or gives up) does the prompt appear. Kernel: - IP is configurable: 0.0.0.0 until leased; NET_SETIP op stores it. - 16-bit frame length. DHCP/BOOTP packets are ~272 bytes, over the old 255-byte frame cap, so net_slip_send takes a 16-bit length, net_pump assembles into a 320-byte buffer with a 16-bit wNetRxLen, and udp_send writes a 16-bit IP total. Payloads stay <=255 (kept small on purpose) so the per-protocol datalen math is unchanged. wNetTx/wNetRxBuf 256->320, SK_RXBUF 208->288. Userland: - c/dhcp.c: DISCOVER->OFFER->REQUEST->ACK over a UDP socket, then net_setip(); times out gracefully (shell still boots) if there's no server. sh.c runs it before the prompt. Bridge (self-contained DHCP server, no dnsmasq): - tunbridge.py + netboot intercept UDP->:67 and answer OFFER/ACK leasing 10.0.0.2 (gateway 10.0.0.1); everything else is bridged/NATed as before. Regression-tested ICMP/UDP/TCP after the 16-bit change. Verified end to end: dhcp: discovering dhcp: leased 10.0.0.2 /# ping 10.0.0.1 -> 4/4 (traffic from the leased address)

net: UDP sockets in the kernel + a DNS resolver (real hostname lookups)

2026-07-17T10:54:43Z

Adds UDP to the kernel socket layer on top of the ICMP core: - net_sum() (raw folded sum) split out of net_cksum() so a UDP pseudo-header (src/dst IP + proto + length) can seed the segment checksum. - udp_send: builds IP+UDP with the pseudo-header checksum; NET_BIND sets the local/source port; net_connect sets the peer. - udp_in: demuxes inbound UDP by destination port to the bound socket (net_find_udp), delivers the payload + source addr. Also fixes a real recv bug: net_pump clobbers BC/DE/HL, so the old recv timeout counted in registers and was effectively random. recv now counts in WRAM. New `nslookup HOST` (PROG_NSLOOKUP=28, bank 30): builds a DNS A query and parses the answer (with 0xC0 name-compression) entirely in userland over a UDP socket - the kernel never sees DNS, just UDP. Verified through the bridge NAT: /# nslookup example.com -> example.com -> 172.66.147.243 This gives us name resolution for the TCP/HTTP demo next.

net: proper socket API in the kernel (SYS_NET) - no more SLIP in userland

2026-07-17T10:39:01Z

The network stack moves into the kernel. src/socket.asm owns SLIP framing, IPv4, RFC1071 checksums, and ICMP; programs now speak a socket API through one syscall (SYS_NET, DE=&netreq dispatched by op): net_socket/connect/send/recv/ close/poll (c/sock.h). No program touches SLIP, IP headers, or checksums. - Socket table (4 sockets) + tx/rx buffers in WRAM0; our IP = 10.0.0.2. - net_pump: drains the link, reassembles SLIP frames, demuxes IPv4. Inbound ICMP echo requests are auto-answered in-kernel, so the GB replies to pings whenever any process pumps RX. - ICMP sockets: send() emits an echo request to the connected peer; recv() returns the matching reply (with a spin/yield timeout). ping.c is now a ~15-line socket client; netd.c is just `for(;;){net_poll(); yield();}`. Verified over tunbridge: /# ping 1.1.1.1 -> replies from the real internet (kernel builds it all) host# ping 10.0.0.2 -> 4/4, 0% loss (kernel auto-answers) Gotchas recorded: gbos.inc isn't a make dep (touch asm after editing); this crt0 doesn't copy initializers (fill arrays at runtime); and the arg string at 0xA000 overlaps _DATA, so parse targets must sit past it (big buffer first). UDP and TCP sockets build on this same core next.