From 0a1df62d8f05a3f1a22b7b283d63d08c7bca8b5b Mon Sep 17 00:00:00 2001
From: Chris Hanson <org/chris-hanson/cph>
Date: Tue, 23 May 2000 00:37:57 +0000
Subject: [PATCH] Fix bug: if there were two memoized connections to the same
 server, GET-IMAP-CONNECTION was returning the first one, even if it was
 closed.  It should look for one that is still open and use it, using the
 closed one only if there's no open one.

---
 v7/src/imail/imail-imap.scm | 55 +++++++++++++++++++++++--------------
 1 file changed, 35 insertions(+), 20 deletions(-)

diff --git a/v7/src/imail/imail-imap.scm b/v7/src/imail/imail-imap.scm
index 19cc79f86..a3c07189e 100644
--- a/v7/src/imail/imail-imap.scm
+++ b/v7/src/imail/imail-imap.scm
@@ -1,6 +1,6 @@
 ;;; -*-Scheme-*-
 ;;;
-;;; $Id: imail-imap.scm,v 1.78 2000/05/22 22:40:09 cph Exp $
+;;; $Id: imail-imap.scm,v 1.79 2000/05/23 00:37:57 cph Exp $
 ;;;
 ;;; Copyright (c) 1999-2000 Massachusetts Institute of Technology
 ;;;
@@ -271,25 +271,32 @@
 	 responses)))))
 
 (define (get-imap-connection url for-folder?)
-  (let loop ((connections memoized-imap-connections) (prev #f))
-    (if (weak-pair? connections)
-	(let ((connection (weak-car connections)))
-	  (if connection
-	      (if (let ((url* (imap-connection-url connection)))
-		    (if for-folder?
-			(eq? url* url)
-			(compatible-imap-urls? url* url)))
-		  connection
-		  (loop (weak-cdr connections) connections))
-	      (let ((next (weak-cdr connections)))
-		(if prev
-		    (weak-set-cdr! prev next)
-		    (set! memoized-imap-connections next))
-		(loop next prev))))
-	(let ((connection (make-imap-connection url)))
-	  (set! memoized-imap-connections
-		(weak-cons connection memoized-imap-connections))
-	  connection))))
+  (let loop ((connections memoized-imap-connections) (prev #f) (near #f))
+    (cond ((weak-pair? connections)
+	   (let ((connection (weak-car connections)))
+	     (if connection
+		 (if (let ((url* (imap-connection-url connection)))
+		       (if for-folder?
+			   (eq? url* url)
+			   (compatible-imap-urls? url* url)))
+		     (if (or for-folder?
+			     (test-imap-connection-open connection))
+			 connection
+			 (loop (weak-cdr connections) connections connection))
+		     (loop (weak-cdr connections) connections near))
+		 (let ((next (weak-cdr connections)))
+		   (if prev
+		       (weak-set-cdr! prev next)
+		       (set! memoized-imap-connections next))
+		   (loop next prev near)))))
+	  (near)
+	  (else
+	   (let ((connection (make-imap-connection url)))
+	     (without-interrupts
+	      (lambda ()
+		(set! memoized-imap-connections
+		      (weak-cons connection memoized-imap-connections))))
+	     connection)))))
 
 (define memoized-imap-connections '())
 
@@ -362,6 +369,14 @@
 	  (lambda ()
 	    (let ((port (imap-connection-port connection)))
 	      (set-imap-connection-port! connection #f)
+	      (let loop ((connections memoized-imap-connections) (prev #f))
+		(if (weak-pair? connections)
+		    (let ((next (weak-cdr connections)))
+		      (if (eq? (weak-car connections) connection)
+			  (if prev
+			      (weak-set-cdr! prev next)
+			      (set! memoized-imap-connections next))
+			  (loop next connections)))))
 	      port)))))
     (if port
 	(close-port port)))
-- 
2.25.1