Add -sNODERAWSOCKETS backend for real TCP & UDP on Node.js#27080
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guybedford wants to merge 3 commits into
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Add -sNODERAWSOCKETS backend for real TCP & UDP on Node.js#27080guybedford wants to merge 3 commits into
guybedford wants to merge 3 commits into
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sbc100
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Nice! I've not yet reviewed the meat of libsockfs.js but looks good so far.
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| // If 1, the POSIX sockets API is backed by Node.js's ``node:net`` module, | ||
| // giving real non-blocking outgoing TCP sockets with no WebSockets, proxy | ||
| // process or pthreads. This only works under node and is ignored elsewhere. |
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You should mention something about how this is similar to what NODERAWFS does for filesystem access?
Speaking of which, should we perhaps combine them? Or at least have NODERAWFS automatically enable NODENET. Its hard to imagine wanting one without that other maybe?
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Also, regarding the name of this settings, should we use the word SOCK rather then NET since that seems to be what we have done previously. I guess -sNODERAWSOCKETS is kind of a mouthfull.
Maybe putting it behind the existing NODERAWFS avoids having to name something new ? :)
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Renamed to -sNODERAWSOCKETS and kept orthogonal to the FS. I think there are use cases for virtual FS as independent? Happy to reconsider merging if you prefer, but I also quite like the two separate options.
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| server = socketserver.TCPServer(('127.0.0.1', 0), EchoHandler) |
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In test_sockets.py we preallocate specific ports, but I guess this maybe even better than doing that?
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I've now extended this PR to server and UDP tests, which do the binding on the Wasm side returning the port. Still without preallocation.
Adds a new NODERAWSOCKETS setting that backs the POSIX sockets API directly with Node.js's node:net module, giving real, non-blocking outgoing (client) TCP sockets without WebSockets, an external proxy process, or pthreads. This is the sockets counterpart to NODERAWFS: where NODERAWFS gives direct access to the host filesystem, this gives direct access to host sockets. Unlike PROXY_POSIX_SOCKETS this is single-threaded and event-driven: socket readiness is delivered through the same emscripten_set_socket_*_callback hooks the default WebSocket backend uses, so it drops into existing readiness reactors unchanged. This initial backend supports outgoing TCP only: connect, send, recv and close, plus get/setsockopt (SO_ERROR, TCP_NODELAY, SO_KEEPALIVE and the TCP keep-alive tunables). There is no bind/listen/accept (server) support and no UDP yet; those land in follow-ups. - new node backend in src/lib/libsockfs_node.js, pulled in only under -sNODERAWSOCKETS, implementing the sock_ops contract over net.createConnection - __syscall_setsockopt now lives in JS (routing to the backend under NODERAWSOCKETS, else reporting the option as unknown), avoiding a libstubs variation - test/sockets/test_tcp_echo.c: a plain POSIX outgoing connect/send/recv echo client that also builds and runs natively, run under node against a loopback echo server started by the test harness
Builds on the outgoing-TCP backend to add bind, listen and accept, so a
program can run a real TCP server under -sNODERAWSOCKETS.
Clients stay on the public node:net API: connect() goes through
net.createConnection and never touches a private handle. Servers need a
synchronous bind() that reports the assigned ephemeral port up front (so a
bind(:0) followed by getsockname() works), which net.Server.listen cannot do
because it is async. For that we use a low-level tcp_wrap TCP handle, whose
bind/getsockname are synchronous, and hand that handle to net.Server.listen for
accept. So process.binding('tcp_wrap') only fires for bind/listen/accept, plus
the rare client that bind()s a source port before connect().
- bind/listen/accept added to the node backend, with poll reporting a listener
readable when a connection is pending
- test/sockets/test_tcp_server.c: a self-contained loopback accept+echo that
also builds and runs natively
Adds connectionless UDP (SOCK_DGRAM) to the node socket backend: bind, sendto/recvfrom and a connect() that records a default peer. node:dgram has no synchronous bind and a dgram.Socket cannot adopt an external handle, so unlike TCP we cannot split UDP into a public client path and a private server path. For now the whole UDP path goes through a low-level udp_wrap handle, which does give a synchronous bind() + getsockname() (so bind(:0) followed by getsockname() returns the assigned port immediately). Once node gains a public dgram bindSync, UDP can move fully onto node:dgram with no private API. - UDP handle helper with onmessage receive wiring; recvStart is deferred until the handle is bound (an unbound handle rejects it), either by an explicit bind or by the auto-bind on first send - bind/connect/sendmsg/recvmsg/poll/close branch for SOCK_DGRAM, with datagram recv returning one message and truncating to the buffer - test/sockets/test_udp_echo.c: a self-contained loopback UDP echo that also builds and runs natively
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I still need to review the details of libsockfs_node.js but the general shape here LGTM!
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This adds a new
-sNODERAWSOCKETSsetting that for supporting direct full sockets on Node.js via thenode:netfor TCP andnode:dgramfor UDP modules, without needingws, an external proxy process, or pthreads.It is layered into three separate commits:
node:netAPIsprocess.binding('tcp_wrap')API to get the raw socket handle, which is also supported on other runtimes like Deno.UDP without JSPI also has to use private APIs in Node.js, but to provide a future path where we might avoid I've also posted nodejs/node#63838 which could lay the groundwork for a fully public API UDP embedding as that is the only blocker.
For comprehensive
setsockoptssupport I also posted nodejs/node#63825 as well so we can close the loop on all options being supported and that is effectively used in a backwards compatible way here despite not landing yet.Note: AI was used to create this PR, under my review.