Fix write hang, WebSocket dispatch, dead rockspec URLs - #373
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send()/SSL_write() return 0 for an empty buffer, which the write handlers mistook for EWOULDBLOCK and kept retrying instead of completing. For write_zero_copy() this spun the ioloop at 100% CPU forever (e.g. serving a zero-length static file); for the regular write() path the callback just silently never fired. Complete an empty buffer immediately in all four write handlers instead of calling send()/SSL_write() with length 0.
_continue_ws called self:open() with no arguments, so route capture groups never reached user handlers even though every other handler gets them via self._url_args. Guard against a nil _url_args too, for handlers not built through normal Application dispatch. Also implement the big-endian frame length/send functions, which were empty stubs and a hard crash on ppc/s390x hosts. On a BE host wire order already equals host order, so these are the LE versions minus the byte-swap calls.
GitHub disabled the unauthenticated git protocol in 2022, so source.url in these rockspecs is unreachable. Switch to git+https for the specs that aren't frozen historical releases. Also add the new websocket spec to the default Docker test run, it's headless and deterministic like the others already there.
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Summary
write("")) used to never complete:send()/SSL_write()legitimately return 0 for an empty buffer, and the write handlers treated any 0 return as "would block, retry" instead of checking completion first. Forwrite_zero_copy()this spun the ioloop at ~100% CPU forever. Fixed in all four write handlers iniostream.lua.WebSocketHandler:open()never received URL route captures, even though every other handler gets them viaself._url_args. Fixed, with a nil guard for handlers not built through normalApplicationdispatch._frame_len_16,_frame_len_64,_send_frame) was a set of empty stubs, a hard crash on ppc/s390x hosts rather than just a byte-order bug. Implemented (wire order already equals host order on BE, so no byte-swap needed). Not tested on real BE hardware, verified by code reading against RFC 6455 only.git://github.com/..., which GitHub disabled in 2022, breakingluarocks install turboentirely. Fixed for the non-frozen rockspecs (turbo-2.1-4,turbo-dev-1).spec/websocket_spec.luaand a couple of regression tests tospec/iostream_spec.lua, and wired the websocket spec into the default CI run.Closes #332, #328, #268, #340
Test plan
make docker-test(default suite): 72/0make docker-test ARGS="spec/iostream_spec.lua": new tests pass, confirmed they fail withSync wait operation timed outagainst the pre-fix codemake docker-test ARGS="spec/websocket_spec.lua": 3/3StaticFileHandler, 200 response in ~3ms, CPU idle afterward