8sync error in procedure select

[Alexey Abramov]

Hi,

I am trying to test an actor I wrote with 8sync. I created a probe actor
which sends messages to the main one. A problem I am having is that when
I want to send a *cleanup* to the main (server) actor from the probe, I
am getting the following backtrace:

--8<---------------cut here---------------start------------->8---
λ guile --debug -s tests/test.scm
Backtrace:
In ice-9/boot-9.scm:
  1736:10 11 (with-exception-handler _ _ #:unwind? _ # _)
In unknown file:
          10 (apply-smob/0 #<thunk 7fac09a7b9a0>)
In ice-9/boot-9.scm:
    718:2  9 (call-with-prompt _ _ #<procedure default-prompt-handle…>)
In ice-9/eval.scm:
    619:8  8 (_ #(#(#<directory (guile-user) 7fac096a0f00>)))
In ice-9/boot-9.scm:
   2806:4  7 (save-module-excursion _)
  4351:12  6 (_)
In 8sync/actors.scm:
    812:6  5 (run-hive #<<hive> 7fac08bdd0c0> _ #:cleanup _ # _)
In ice-9/control.scm:
    91:24  4 (call-with-escape-continuation _)
In 8sync/agenda.scm:
    569:6  3 (run-agenda #<<agenda> queue: (() . #f) prompt-tag: ("…> …)
    470:7  2 (update-agenda-from-select! #<<agenda> queue: (() . #f)…>)
In ice-9/boot-9.scm:
  1731:15  1 (with-exception-handler #<procedure 7fac08bbd240 at ic…> …)
In unknown file:
           0 (select (#<closed: file 7fac07ff6460>) () () #f #f)

ERROR: In procedure select:
In procedure select: Wrong type argument in position 1: #<closed: file 
7fac07ff6460>
--8<---------------cut here---------------end--------------->8---

I have attached a simple snippet to reproduce the problem, and also a
naive patch I did. I am not sure if it is me doing the shutdown wrong, or
it's a bug.

-- 
Alexey


>From 020cdb7f7915876ff808b37430846a26dfab702b Mon Sep 17 00:00:00 2001
From: Alexey Abramov <leven...@mmer.org>
Date: Mon, 3 May 2021 16:53:04 +0200
Subject: [PATCH] agenda: Honor closed ports

* 8sync/agenda.scm (update-agenda-from-select!)[ports-to-select?]:
Cleanup ports which have been closed, before monitoring them with
select.
---
 8sync/agenda.scm | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/8sync/agenda.scm b/8sync/agenda.scm
index e91487e..6b851a8 100644
--- a/8sync/agenda.scm
+++ b/8sync/agenda.scm
@@ -514,6 +514,13 @@ Also handles sleeping when all we have to do is wait on the schedule."
       (not (= (hash-count (const #t)
                           (selector agenda))
               0)))
+    (define (drop-closed-ports! table)
+      (for-each (lambda (port)
+                  (when (port-closed? port)
+                    (hash-remove! table port)))
+                (hash-keys table)))
+    (drop-closed-ports! (agenda-write-port-map agenda))
+    (drop-closed-ports! (agenda-read-port-map agenda))
     (or (has-items? agenda-read-port-map)
         (has-items? agenda-write-port-map)))
 
-- 
2.31.1

test.scm
Description: Binary data