From 881fd3bbe869d0b7210174632d8e71bab400f4b1 Mon Sep 17 00:00:00 2001
From: "Taylor R. Campbell" <net/mumble/campbell>
Date: Mon, 11 Aug 2008 17:51:12 +0000
Subject: [PATCH] Remember what IMAP message keywords have been cached on disk,
 and avoid stat(2)ing the cache files if we already expect them to exist. This
 dramatically expedites repeated scanning of the message cache (for preloading
 folder outlines when sorting or summarizing).

---
 v7/src/imail/imail-imap.scm | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/v7/src/imail/imail-imap.scm b/v7/src/imail/imail-imap.scm
index ccc714a49..b68c20c52 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 1.220 2008/08/11 17:44:50 riastradh Exp $
+$Id: imail-imap.scm,v 1.221 2008/08/11 17:51:12 riastradh Exp $
 
 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
     1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
@@ -1042,7 +1042,8 @@ USA.
   (length)
   (envelope)
   (bodystructure)
-  (body-parts define standard initial-value '()))
+  (body-parts define standard initial-value '())
+  (cached-keywords define standard initial-value '()))
 
 (define-generic imap-message-uid (message))
 (define-generic imap-message-length (message))
@@ -1272,7 +1273,7 @@ USA.
 	     (lambda (index message)
 	       (if (zero? (remainder index 10))
 		   (imail-ui:progress-meter index length))
-	       (let ((keywords (message-uncached-keywords message keywords)))
+	       (let ((keywords (select-uncached-keywords message keywords)))
 		 (if (pair? keywords)
 		     (begin
 		       (hash-table/modify! message-sets keywords
@@ -1281,9 +1282,20 @@ USA.
 		       (set! count (+ count 1)))))))))))
     (values message-sets count)))
 
-(define (message-uncached-keywords message keywords)
+(define (imap-message-keyword-cached? message keyword)
+  (let ((cached-keywords (imap-message-cached-keywords message)))
+    (or (memq keyword cached-keywords)
+	(and (file-exists? (message-item-pathname message keyword))
+	     (begin
+	       (set-imap-message-cached-keywords!
+		message
+		(cons keyword cached-keywords))
+	       #t)))))
+
+(define (select-uncached-keywords message keywords)
   (delete-matching-items keywords
-    (lambda (keyword) (file-exists? (message-item-pathname message keyword)))))
+    (lambda (keyword)
+      (imap-message-keyword-cached? message keyword))))
 
 ;;;; MIME support
 
@@ -1610,6 +1622,11 @@ USA.
 		    (if (memq keyword message-items-cached-as-string)
 			(string->file item pathname)
 			(simple-write-file item pathname))
+		    (let ((keywords (imap-message-cached-keywords message)))
+		      (if (not (memq keyword keywords))
+			  (set-imap-message-cached-keywords!
+			   message
+			   (cons keyword keywords))))
 		    (save-item keyword item))))
 	    (imap:response:fetch-attribute-keywords response)))
 
-- 
2.25.1