1b0d640f73
A fiber can block on a file descriptor and the run loop blocks on kevent until the kernel reports it ready. Reuses the existing std/net/kqueue.sx bindings. Scheduler gains a lazy kq fd + an io_waiters list; block_on_fd arms a one-shot EVFILT_READ registration, records an IoWaiter, and suspends. Run-loop Mode 2: when the ready queue drains and no timer is pending, block on kq_wait(-1), match each fired ident to its waiter, evict it, wake the fiber. wake evicts a pending fd-waiter (cancel_io_waiter_for) so no stale IoWaiter outlives a reaped fiber. Adversarial review found two CRITICALs: (1) two fibers on the same fd share one kqueue registration (macOS EV_ADD replaces), so one is lost and the loop hangs -- fixed by enforcing one-waiter-per-fd with a loud abort; (2) an fd-waiter on a never-ready fd 'hangs' -- reclassified as correct event-loop semantics (a server idling on a socket), with the misleading orphan-check comment corrected. UAF parity, ident width, EINTR handling, timer/io precedence all probed safe. Example: 1816 (pipe roundtrip -- reader blocks, writer writes, reader wakes via kqueue). macOS only; linux epoll twin deferred. Suite green 754/0.
35 KiB
35 KiB