zlib: Fix memory leak due to revealed ports not being GC'd.

Fixes <https://bugs.gnu.org/28784>.

This mostly reverts 81a0f1cdf12e7bcc34c1203f034a323fa8f52cf5, which
introduced a regression: revealed ports are *never* GC'd (contrary to
what Guile's manual suggests).

In addition to the revert, 'close-procedure' now explicitly swallows
EBADF errors when 'close-port' is called.

* guix/zlib.scm (close-procedure): New procedure.
(make-gzip-input-port)[gzfile]: Use 'fileno' instead of 'port->fdes'.
Use 'close-procedure' instead of 'gzclose'.
(make-gzip-output-port): Likewise.
* tests/zlib.scm ("compression/decompression pipe"): Use 'port-closed?'
to determine whether PARENT has been closed.

1 files changed, 1 insertions, 10 deletions

diff --git a/tests/zlib.scm b/tests/zlib.scm
index f71609b7c5..5455240a71 100644
--- a/tests/zlib.scm
+++ b/tests/zlib.scm
@@ -57,16 +57,7 @@
               (match (waitpid pid)
                 ((_ . status)
                  (and (zero? status)
-
-                      ;; PORT itself isn't closed but its underlying file
-                      ;; descriptor must have been closed by 'gzclose'.
-                      (catch 'system-error
-                        (lambda ()
-                          (seek (fileno parent) 0 SEEK_CUR)
-                          #f)
-                        (lambda args
-                          (= EBADF (system-error-errno args))))
-
+                      (port-closed? parent)
                       (bytevector=? received data))))))))))))
 
 (test-end)