GeezerVison

Summary

Add real TCP/UDP socket operations for wasm32-wasip1 through an opt-in wasix feature, tested with Wasmer 7.5.0.

• Connect socket construction, bind/listen/accept/connect, send/receive, forward DNS and endpoint names to the WASIX host ABI.
• Support blocking, nonblocking and timeout operations with polling, byte-buffer I/O, makefile, sendfile, duplication and descriptor ownership.
• Fix the WebAssembly constructor's positional/keyword arguments. Remove fabricated fd 0, successful no-op socket options and invented addresses.
• Keep portable preview1 builds free of WASIX imports. Unsupported hosts reject socket construction with ENOTSUP.
• Add loopback and denied-capability tests to the WASI CI job. Native Unix/Windows socket implementation and hot paths are unchanged.

Validation

• Wasmer guest integration at 703423b4d2: 22 tests passed, including IPv4/IPv6 TCP, UDP, DNS, timeouts, partial reads, file-like I/O, an actual HTTPServer request/response, and descriptor lifetime/error cases.
• Networking disabled: real ENOTSUP, no fabricated success.
• Portable preview1 without the feature: explicit unsupported socket construction passed.
• Host ABI layout/unit tests: 3 passed under Wasmer; additional probes covered explicit protocols, socket options and raw descriptor ownership.
• WASI Clippy at 703423b4d2, with and without wasix: passed with no warnings in changed code; existing unrelated WASI warnings remain.
• Pre-commit hooks and actionlint passed. Zizmor has no new findings; the same four low-severity findings exist on main, and the medium-or-higher scan passes.
• Native workspace tests and doctests: 1,542 passed, 20 ignored, 0 failed.
• Separate C API tests: 149 passed, 2 ignored, 0 failed.
• Native workspace and separate C API strict Clippy (--all-targets -- -D warnings): passed.
• Native release at 564694cf31: 58 selected socket regressions ran: 56 passed and 2 existing skips, covering TCP/UDP, socket pairs, nonblocking I/O, file objects, timeouts, buffers and server helpers.
• Native loopback timing sanity check: 2,000 bidirectional 32-byte round trips, 7 samples, median 10.13 ms. No exact-main optimized binary was available, so this is not a controlled performance-regression comparison.

The unchanged stdlib_socket snippet under WASIX stops at its assumption that one recv() returns an entire sent file. WASIX can return a valid short read. The new integration test checks the complete 32 KiB transfer with a receive loop; no existing assertion or skip was changed.

Native full-suite limits were also recorded rather than hidden:

• -m test test_socket aborts in dns-lookup 4.0.2 while decoding a localized error (test_getaddrinfo_localized_error, UTF-8 unwrap, exit 101).
• The native stdlib_socket snippet reaches its NETLINK case and fails with host EPERM.
• Both outcomes reproduce with the previously built 38d813fba3 interpreter using this branch's same Lib. Native socket implementation files are unchanged by this PR. The final 703423b4d2 follow-up changes only the WASM socket module, WASIX integration test and documentation; native gates above ran at 564694cf31.

Host requirements and limits

WASIX extensions are not standard WASI preview1. The feature needs a host providing wasix_32v1 and networking permission, such as Wasmer's --net. It is opt-in so ordinary preview1 artifacts remain portable.

This does not add Unix/raw sockets, ancillary messages, multicast configuration, reverse DNS, system hostname/service lookup, IPv6 scope IDs or TLS. Unsupported flags/options fail explicitly. Wasmer cannot identify the type of rewrapped TCP listeners or bound UDP sockets; these require explicit constructor metadata, and SO_TYPE reports ENOTSUP if the host cannot establish the actual type.

Build/run instructions and capability details: wasm/WASIX.md.

AI assistance: OpenAI Codex implemented the backend, tests and documentation and ran the listed validation. The runtime did not expose its model version.