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Make blocking socket FFI collect-safe; fix http-client temp-file race

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Two thread-safety bugs in the native FFI layer.

The HTTP server's accept/recv/send were plain foreign-procedures. A thread
inside a foreign call stays active for the stop-the-world collector, so the
accept loop sitting idle in accept() froze GC for the whole process whenever
another thread (a future, an async block) allocated. Mark the three blocking
calls __collect_safe so the thread deactivates for the call's duration —
collection proceeds while the accept thread waits. The args are an fd and
foreign-alloc'd buffers (outside the Scheme heap), so a collection mid-call has
nothing to move.

jolt.http-client built its -D header-file path from an unguarded (set! counter
(+ counter 1)) and counter mod 90000, with no per-process component. Concurrent
requests could compute the same path and clobber each other's headers. Use a
mutex-guarded monotonic counter plus the pid.

test/chez/ffi-server-test.ss exercises both (a (collect) while the server is
idle in accept(), temp-path uniqueness across threads, and a live request) and
is wired into the gate as `make ffi`.
This commit is contained in:
Yogthos 2026-06-22 08:12:53 -04:00
parent 4114766c71
commit 6f433a1b3c
4 changed files with 97 additions and 8 deletions
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9
Makefile
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@ -4,7 +4,7 @@
# build step. `make test` is the full gate. `make remint` rebuilds the seed after a
# source change.
.PHONY: test ci values corpus unit smoke selfhost sci certify remint
.PHONY: test ci values corpus unit smoke selfhost sci certify ffi remint
# Full gate (dev machine). Includes the self-host byte-fixpoint, which only holds
# on the same Chez that minted the seed.
@ -15,7 +15,7 @@ test: selfhost ci
# lockfile) — it RUNS correctly on any Chez, but `selfhost` rebuilds it and a
# different Chez version may emit byte-different (gensym/order) output, so the
# byte-fixpoint is a dev-machine check, not a CI one (jolt-8479).
ci: values corpus unit smoke sci certify
ci: values corpus unit smoke sci ffi certify
@echo "OK: CI gates passed"
# Self-host fixpoint: bootstrap.ss rebuild == checked-in seed.
@ -42,6 +42,11 @@ smoke:
sci:
@chez --script host/chez/run-sci.ss
# FFI + threading: HTTP server GC-safety (blocking calls deactivate the thread)
# and http-client temp-file uniqueness, plus a live request.
ffi:
@chez --script test/chez/ffi-server-test.ss
# JVM oracle: certify the corpus against reference Clojure. Skips if clojure absent.
certify:
@if command -v clojure >/dev/null 2>&1; then \