Let a link's receiver find its streams' inputs again (017, stage 3)

A stream finds its input once, when it is made; an app that starts again
with another module may have the input at another number, of another
shape, or none. pure_link_receiver_rebind marks the streams to inputs of
a prefix stale: each finds its input again by name, with the fields it
was laid out with, before its next delivery and at its sender's next
packet, keeping what it holds; one none takes is refused as a new one
would be. pure_link_listener_rebind asks it of the listener's thread.
test-link's rebound case stops its app, starts it with the input at
another number, then of another shape taken by name: all 3,000 records
come once, in order (without the rebind, none after the stop).

1 files changed, 4 insertions, 0 deletions

diff --git a/link/link.h b/link/link.h
index 9846af4..40fc9f9 100644
--- a/link/link.h
+++ b/link/link.h
@@ -51,5 +51,9 @@ PureLinkListener *pure_link_listen(PureLinkReceiver *, unsigned port, char *erro
 bool pure_link_serve(PureLinkListener *, char *error, size_t size);
 /* How a delivery went: link-protocol.h's PureLinkDone, with its token. */
 void pure_link_done(PureLinkListener *, PureLinkDone);
+/* The host's inputs whose names begin with prefix may be others now: the
+ * receiver's streams to them find theirs again (pure_link_receiver_rebind),
+ * on the listener's thread; any thread. */
+void pure_link_listener_rebind(PureLinkListener *, const char *prefix);
 void pure_link_listener_close(PureLinkListener *, PureLinkCounts *counts);
 #endif