[yaws_sup] Fix RSS startup deadlock by reordering child specs#504
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QuinnWilton wants to merge 1 commit intoerlyaws:masterfrom
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[yaws_sup] Fix RSS startup deadlock by reordering child specs#504QuinnWilton wants to merge 1 commit intoerlyaws:masterfrom
QuinnWilton wants to merge 1 commit intoerlyaws:masterfrom
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yaws_server:init calls yaws_config:load, which calls yaws_rss:open/2 when the config contains an <rss> section. yaws_rss:open blocks in wait_for_server if yaws_rss is not registered. Move yaws_sup_restarts (parent of yaws_rss) before yaws_server in the child spec list so yaws_rss is available when config loading needs it. Add regression tests that drive through yaws_config:load with a real RSS config file, proving the deadlock occurs without yaws_rss and resolves with it running.
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Note that this issue was found while running a static analysis tool I'm working on. It seems like a legitimate finding, but it isn't something I observed while operating
yaws, and so there might be some nuance I'm missing.yaws_server:initcallsyaws_config:load, which callsyaws_rss:open/2when the config contains an section.yaws_rss:openblocks inwait_for_serverifyaws_rssis not registered. Moveyaws_sup_restarts(parent ofyaws_rss) beforeyaws_serverin the child spec list soyaws_rssis available when config loading needs it.Add regression tests that drive through
yaws_config:loadwith a real RSS config file, proving the deadlock occurs withoutyaws_rssand resolves with it running.