gbos.git/c/wget.c, 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: wget-by-hostname + shared DNS resolver (a Game Boy fetches example.com)

2026-07-17T11:11:53Z

resolve.h: shared helper that turns a dotted-quad or a hostname into an IPv4 address (DNS A query over a UDP socket to 1.1.1.1). nslookup now uses it and slims down; wget uses it so you can name a host directly. wget HOST|IP now: resolve -> TCP connect -> "GET / HTTP/1.0" with the real Host header -> stream the body to the LCD/console until EOF. One command does DNS + TCP + HTTP, all on the kernel socket layer. Verified over tunbridge's NAT against the real internet: /# wget example.com connecting 172.66.147.243 HTTP/1.1 200 OK Server: cloudflare Example Domain... [eof] The full HTML page arrives across many TCP segments and is reassembled and printed - real DNS, real TCP, real HTTP, fetched by a Game Boy by name. (tunbridge.py already sets up + tears down the NAT, so the demo is a one-liner: sudo python3 tools/tunbridge.py "wget example.com")

net: TCP sockets in the kernel - a Game Boy fetches HTTP over real TCP

2026-07-17T11:06:38Z

Kernel TCP client on the socket layer: net_connect(SOCK_TCP) runs the 3-way handshake in-kernel, send()/recv() drive the byte stream, close() does the FIN. - Socket gains state + 32-bit snd_nxt/rcv_nxt (big-endian, add-with-carry-fold). - tcp_send_seg builds IP+TCP with a pseudo-header checksum; the SYN carries an MSS option (200) so the peer never sends a segment larger than our 256-byte frame buffer (we don't do IP reassembly). - tcp_in state machine: SYN_SENT->ESTABLISHED on SYN-ACK, buffers in-order data and ACKs it, handles FIN -> recv() returns 0 (EOF). - No retransmission: the GB<->host link is lossless and the host's real TCP owns the internet side - which removes TCP's hardest part. - net_pump now processes one frame per call so recv drains each segment before the next arrives (single rx slot, no overwrite). wget.c is now a thin socket client: connect -> send "GET / HTTP/1.0" -> recv to EOF -> print. Verified end to end against a host HTTP server: /# wget 10.0.0.1 HTTP/1.0 200 OK Hello from a real HTTP server, fetched by a Game Boy! with a clean SYN/SYN-ACK/ACK ... PSH ... FIN/ACK trace on the wire.

net: wget - real HTTP over the link port via the gateway

2026-07-16T23:31:38Z

Grow the link-port demo from echo to actual network access. The Game Boy still only does SLIP framing + display; the host gateway does DNS/TCP/HTTP. - c/netlib.h: SLIP framing factored out (header-only, per-program copy). necho.c now uses it too. - c/wget.c: `wget URL` frames the URL, then prints the reply body. The gateway streams the body back as typed frames: 'D' ... 'E'. - tools/gateway.py: add --mode http (urlopen the frame as a URL, cap the body, chunk it) alongside --mode echo; --cmd runs any gbos command. Verified: `wget example.com` streams back the full Example Domain HTML onto the terminal; `wget sl0p.foo` fetches the real page. A Game Boy on the web, over the link cable.