Let a receiver whose app is full keep what came, and say so

A link's delivery the app had no room for was handed over again at the
next turn: a receiver over its memory budget would refuse the same
records as fast as the owner could apply them. And its sender, seeing
records received but not stored for a second, sent the whole window
again every second.

Now a host says a delivery found it full (PureLinkDone.full). The
receiver keeps the records and hands them over again after a pause, 100
ms doubling to 500 ms, and meanwhile its STORED frames carry flag 2: the
app is full and what came is kept. A sender hearing it starts its
one-second wait for the save again, and sends none of it again. The
spec (012) says both sides; the pause is a local choice that must stay
under the sender's wait.

pure_link_done takes the PureLinkDone itself. test-link's new case keeps
the app full for 5 s: 12 hand-overs meanwhile, taken within 0.5 s of
having room, and no record sent again (21,640 without the flag).

1 files changed, 2 insertions, 1 deletions

diff --git a/serve/serve.c b/serve/serve.c
index 38111a3..95ac37f 100644
--- a/serve/serve.c
+++ b/serve/serve.c
@@ -1710,7 +1710,8 @@ static void hand_back(void *context, Applied *applied, size_t count) {
         events = events || applied[i].waiter;
         LinkJob *link = applied[i].link;
         if (!link) continue; /* records a link delivered: stored now, or not */
-        pure_link_done(link->listener, link->token, applied[i].heard, applied[i].status == PURE_OK, applied[i].gap);
+        pure_link_done(link->listener, (PureLinkDone){link->token, applied[i].heard, applied[i].status == PURE_OK,
+                                                     applied[i].gap, false});
         free(link->ingress);
         free(link);
     }