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fix(gateway): wake WebChat writes on the lws service thread - #127
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lws_callback_on_writable updates the poll set without the per-thread lock. Replies and provider-status broadcasts called it from the agent thread while lws_service ran on the gateway thread, racing pollfd updates and a closing wsi. Queue the frame, cancel the service wait, and mark writable only from EVENT_WAIT_CANCELLED. Co-authored-by: esadrianno <esadrianno@gmail.com>
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WebChat replies and provider-status broadcasts called
lws_callback_on_writable()from the agent thread whilelws_service()ran on the gateway thread. In libwebsockets 4.3 that call updates the poll set without the per-thread lock, so a live reply can race the service thread and touch awsithatLWS_CALLBACK_CLOSEDis already tearing down. The process can crash, or the queued frame is never flushed and the browser never sees the reply.ws_send_toandws_broadcast_textnow only queue the text and calllws_cancel_service(), which is safe from another thread.LWS_CALLBACK_EVENT_WAIT_CANCELLED(delivered on the service thread to every protocol, with a fakewsi) callsws_on_service_cancel()to mark real connections that still have queued text.http_stopclears the stored context beforelws_context_destroy.Validation:
make test_ws(including the new wake tests) passed.src/gateway/ws.c,http_lws.c, andhttp.ccompiled with-Wall -Wextraagainst libwebsockets 4.3.3.GATEWAY=0 make testbuilt and ran the unit suite;test_routes_hardwarestill tries to link after its GATEWAY=0 skip line, which is existing makefile behavior and unrelated to this change.