Adds the spec's one and only src/controller/ change: a new
case OPCode_schedAdmin in myreq_handler() (cluster.c) that mirrors the
existing OPCode_upgradeConfig case -- primary-only gate, explicit reply
on every path, stateless pass-through with no WAL entry.
Forwards to the scheduler via a new xce_schedadmin_req() (async send,
mirrors xce_fetchfile_req) and blocks the vtask thread on a condvar with
a 5s deadline while holding c->sched.lock for the round-trip, matching
this spec's own research-phase design decision (parity with
OPCode_upgradeConfig's no-RBAC posture, blocking wait accepted for
low-frequency admin traffic). A new branch in the existing
OPCode_reply case demuxes the scheduler's SchedAdminReply to a
process-global single-slot pending-waiter mechanism, serialized by
c->sched.lock, matching job.c's existing fetchfile-proxy pattern.
Adversarial review independently traced double-free/cleanup, the
timeout/signal race, and reply-opcode demux correctness against source;
found and a follow-up round closed a narrow-window leak via a carefully
lock-ordered unlock->unregister->relock sequence (avoiding an AB-BA
inversion against schedadmin_signal()'s lock acquisition order).
New test_sched_admin_dispatch.c drives the real myreq_handler via the
existing myreq_handler_for_test seam: not-primary rejection (proven via
a poison-pointer sched.ep that would crash if forwarding were ever
attempted), not-connected rejection, and a genuine two-thread round-trip
test exercising the real signal/demux path.
Controller suite 3/3 (1090/1090 assertions), scheduler suite 26/26
unaffected, clang-format clean.
Rongsong Shen
045be6b3d6
