pushPostToClient sizes the body with strlen(post.text) for the payload and
the expected ACK alike. The web API will store "a\0b", and pushing it whole
sends text the receiver cannot see -- it stops at the NUL -- while hashing
the pending ACK over a span the receiver never reproduces. The push would
then never be acknowledged and would retry into the failure backoff.
Same defect the core builder had; this is a second, hand-rolled builder.
Also proves MC-R4 end to end at last: a genuinely encrypted guest PLAIN
through a real registered room identity, watching the injector for an ACK
that must not appear. The seam was only covered in three separate halves
before -- core honours a veto, _may_ack computes one, a mocked constructor
receives one -- none of which would have caught the wiring being dropped.
agessaman
2cf65abf62