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Fix data race in welcome_response() via localtime() - #13
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welcome_response() runs on worker threads and called localtime(), which is not reentrant: it mutates a static struct tm shared process-wide. Confirmed under ThreadSanitizer (data race via tzset_internal). Replaced with localtime_r() on POSIX and localtime_s() on Windows. Regression test: test/test_reentrancy.c runs 32 concurrent welcome-page requests; it reported the race under TSan before the fix and is clean after. Wired into Make, CMake, Meson and CI. The new test binds port 18780, not 18779: meson runs its tests in parallel and test_security already binds 18779, so the two collide.
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Fixes #7.
welcome_response()callslocaltime()from worker threads — not reentrant, it mutates a staticstruct tmshared process-wide. Confirmed under ThreadSanitizer (data race viatzset_internal). Fixed withlocaltime_r()/localtime_s()(Windows).Tests:
test/test_reentrancy.c— 32 concurrent welcome-page requests; reported the race under TSan before the fix, clean after. Wired into Make, CMake, Meson and CI.Stacked on the previous PR in the series; merge in order.