controller.capnp declared `struct Data $C.mapname("xce_data_t")` (an
OPCode_get query-result tagged union) at file scope, which shadows
Cap'n Proto's builtin Data blob type for every later `: Data` field in
the same file. This silently miscompiled 7 fields across 6 structs as
a struct-pointer type instead of a raw byte blob: UpgradeConfigRequest
.sha256/.bytes, ReplConfigReply.sha256/.bytes, ReplConfigPushRequest
.sha256/.bytes, ReplEnvelope.payload, SnapshotTransfer's chunk
payload, WalCatchupEntry.payload/.batchPayloads, and CtrlHelloRequest
.key. Production C code had already routed around it for years via
hand-rolled raw capn_ptr manipulation (see request.c's own comments);
nothing before now needed the generated codec/accessors to actually
work for these fields.
Renamed the local struct to XceData (capnp-level name only; the
$C.mapname("xce_data_t") C typedef is unchanged) and explicitly
repointed getdata/pushmsg at XceData by name, since those two fields
correctly want the local tagged union. Updated every derived
generated-identifier reference across 19 hand-written files spanning
controller, lib, scheduler, and the Go apiserver/xcecli CGo bindings.
Fixed 5 call sites in lib/request.c that had been typed against the
old workaround alias but now legitimately receive the correct
capn_data type (a pure type-name swap -- Data_ptr/XceData_ptr and
capn_data share the identical {capn_ptr p} layout).
Verified via full rebuild+test: lib (1/1), controller (3/3, incl. the
job-array push regression tests), scheduler (15/15), Go apiserver +
xcecli (all packages green), and a direct pycapnp round-trip proving
UpgradeConfigRequest.sha256/.bytes now encode/decode correctly.
Bug: bug-1461 (.wolf/buglog.json). Unblocks admin-config-tool task 3.3.
Crash: encode_NameValue_list called with count=21, s=NULL on worker
rejoin, causing SIGSEGV in persist_worker_hook_fun.
Root cause: free_name_val_list(xce_name_val_t***, int) accepted count by
value. It zeroed *vals (resvals_to_sched = NULL) but could not zero
nresvals_to_sched. Any caller that freed the scheduler resource snapshot
(opget.c workerlist, reply.c clusterconf, dataex.c, sched.c dispatch)
left nresvals_to_sched stale. When the worker later rejoined and the
WAL HOOK fired, the WAL encoder read count=21 with a NULL pointer.
Fix: change signature to free_name_val_list(xce_name_val_t***, int*)
so both fields are zeroed atomically. Update all 7 call sites.