From 146760d4ac8b88b713732df08883c4dfe2017481 Mon Sep 17 00:00:00 2001
From: Jessica Tallon <tsyesika@tsyesika.se>
Date: Tue, 29 Aug 2023 13:00:13 +0200
Subject: [PATCH] Send op:gc-export with the correct wire delta on GC

---
 goblins/ocapn/captp.rkt | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/goblins/ocapn/captp.rkt b/goblins/ocapn/captp.rkt
index f0b6489..2679375 100644
--- a/goblins/ocapn/captp.rkt
+++ b/goblins/ocapn/captp.rkt
@@ -269,7 +269,7 @@
   #:transparent)
 (struct cmd-send-gc-answer (answer-pos)
   #:transparent)
-(struct cmd-send-gc-export (export-pos)
+(struct cmd-send-gc-export (export-pos wire-delta)
   #:transparent)
 
 ;; utility for splitting up keyword argument hashtable in a way usable by
@@ -409,13 +409,7 @@
   (define (increment-spare-imports-count! import-pos)
     (hash-set! spare-import-counts import-pos
                (add1 (hash-ref spare-import-counts import-pos 0))))
-  ;; Go through all the "spare imports" and reset them
-  (define (handle-spare-imports!)
-    (for ([(import-pos count) (in-hash spare-import-counts)])
-      ;; Send a gc-export message for this many
-      (send-to-remote (op:gc-export import-pos count))
-      ;; Reset these
-      (hash-remove! spare-import-counts import-pos)))
+
   (define (decrement-exports-count-maybe-remove! export-pos delta)
     (-> integer? integer? any/c)
     (match (hash-ref export-counts export-pos #f)
@@ -470,7 +464,9 @@
   (define (make-import-will-handler import-pos)
     (lambda _
       (hash-remove! imports import-pos)
-      (<-np-extern internal-handler (cmd-send-gc-export import-pos))))
+      (<-np-extern internal-handler
+                    (cmd-send-gc-export import-pos
+                                        (add1 (hash-ref spare-import-counts import-pos 0))))))
   (define (install-import-will-handler! refr import-pos)
     (will-register refr-will-executor refr
                    (make-import-will-handler import-pos)))
@@ -717,14 +713,6 @@
             [(keyword? arg) (values args (cons arg kw-args) kw-vals #t)]
             [else (values (cons arg args) kw-args kw-vals #f)])))
 
-  ;; !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-  ;; TODO TODO TODO: EACH of these needs to call (handle-spare-imports!)
-  ;; at the end of its behavior!  Probably the best thing to do is to
-  ;; make a wrapper for each of these that does so... and also which
-  ;; adds an error handler which aborts the whole thing if such an
-  ;; error occurs
-  ;; !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-
   (define ((^captp-incoming-handler bcom) msg)
     (unless running?
       (error 'captp-breakage "Captp session is no longer running but got ~a"
@@ -860,8 +848,8 @@
          (send-to-remote listen-msg)]
         [(cmd-send-gc-answer (? integer? answer-pos))
          (send-to-remote (op:gc-answer answer-pos))]
-        [(cmd-send-gc-export (? integer? export-pos))
-         (send-to-remote (op:gc-export export-pos 1))]))
+        [(cmd-send-gc-export (? integer? export-pos) (? integer? wire-delta))
+         (send-to-remote (op:gc-export export-pos wire-delta))]))
     (define (broken-handle-cmd cmd)
       (match cmd
         [(cmd-send-message msg)
@@ -877,7 +865,7 @@
          (<-np listener-refr 'break (captp-session-severed))]
         [(cmd-send-gc-answer (? integer? answer-pos))
          'no-op]
-        [(cmd-send-gc-export (? integer? export-pos))
+        [(cmd-send-gc-export (? integer? export-pos) (? integer? wire-delta))
          'no-op]))
     (if running?
         (running-handle-cmd cmd)