X-Git-Url: http://cgit.sxemacs.org/?p=gnus;a=blobdiff_plain;f=lisp%2Fnnmaildir.el;h=3d8926b69259685040b88fddd8124ae83be54f62;hp=aafc9771c5c32187813cb9e2643b73fe6ce0f7cc;hb=HEAD;hpb=125f9b27ec2afd22c3619109f4fa7beba346726c

diff --git a/lisp/nnmaildir.el b/lisp/nnmaildir.el
index aafc9771c..3d8926b69 100644
--- a/lisp/nnmaildir.el
+++ b/lisp/nnmaildir.el
@@ -1,14 +1,15 @@
 ;;; nnmaildir.el --- maildir backend for Gnus
-;; Public domain.
+
+;; This file is in the public domain.
 
 ;; Author: Paul Jarc <prj@po.cwru.edu>
 
 ;; This file is part of GNU Emacs.
 
-;; GNU Emacs is free software; you can redistribute it and/or modify
+;; GNU Emacs is free software: you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
-;; any later version.
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
 
 ;; GNU Emacs is distributed in the hope that it will be useful,
 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -16,9 +17,7 @@
 ;; GNU General Public License for more details.
 
 ;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING.  If not, write to the
-;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-;; Boston, MA 02111-1307, USA.
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
 
 ;;; Commentary:
 
@@ -41,15 +40,12 @@
 ;;   copying, restoring, etc.
 ;;
 ;; Todo:
-;; * Merge the information from <URL:http://multivac.cwru.edu./nnmaildir/>
-;;   into the Gnus manual.
-;; * Allow create-directory = ".", and configurable prefix of maildir names,
-;;   stripped off to produce group names.
+;; * When moving an article for expiry, copy all the marks except 'expire
+;;   from the original article.
 ;; * Add a hook for when moving messages from new/ to cur/, to support
 ;;   nnmail's duplicate detection.
-;; * Allow each mark directory in a group to have its own inode for mark
-;;   files, to accommodate AFS.
 ;; * Improve generated Xrefs, so crossposts are detectable.
+;; * Improve code readability.
 
 ;;; Code:
 
@@ -59,23 +55,75 @@
    (put 'nnmaildir--with-work-buffer 'lisp-indent-function 0)
    (put 'nnmaildir--with-nov-buffer  'lisp-indent-function 0)
    (put 'nnmaildir--with-move-buffer 'lisp-indent-function 0)
+   (put 'nnmaildir--condcase         'lisp-indent-function 2)
    )
 ]
 
-(eval-and-compile
-  (require 'nnheader)
-  (require 'gnus)
-  (require 'gnus-util)
-  (require 'gnus-range)
-  (require 'gnus-start)
-  (require 'gnus-int)
-  (require 'message))
+(require 'nnheader)
+(require 'gnus)
+(require 'gnus-util)
+(require 'gnus-range)
+(require 'gnus-start)
+(require 'gnus-int)
+(require 'message)
+(require 'nnmail)
+
 (eval-when-compile
-  (require 'cl)
-  (require 'nnmail))
+  (require 'cl))
 
 (defconst nnmaildir-version "Gnus")
 
+(defconst nnmaildir-flag-mark-mapping
+  '((?F . tick)
+    (?P . forward)
+    (?R . reply)
+    (?S . read))
+  "Alist mapping Maildir filename flags to Gnus marks.
+Maildir filenames are of the form \"unique-id:2,FLAGS\",
+where FLAGS are a string of characters in ASCII order.
+Some of the FLAGS correspond to Gnus marks.")
+
+(defsubst nnmaildir--mark-to-flag (mark)
+  "Find the Maildir flag that corresponds to MARK (an atom).
+Return a character, or nil if not found.
+See `nnmaildir-flag-mark-mapping'."
+  (car (rassq mark nnmaildir-flag-mark-mapping)))
+
+(defsubst nnmaildir--flag-to-mark (flag)
+  "Find the Gnus mark that corresponds to FLAG (a character).
+Return an atom, or nil if not found.
+See `nnmaildir-flag-mark-mapping'."
+  (cdr (assq flag nnmaildir-flag-mark-mapping)))
+
+(defun nnmaildir--ensure-suffix (filename)
+  "Ensure that FILENAME contains the suffix \":2,\"."
+  (if (gnus-string-match-p ":2," filename)
+      filename
+    (concat filename ":2,")))
+
+(defun nnmaildir--add-flag (flag suffix)
+  "Return a copy of SUFFIX where FLAG is set.
+SUFFIX should start with \":2,\"."
+  (unless (gnus-string-match-p "^:2," suffix)
+    (error "Invalid suffix `%s'" suffix))
+  (let* ((flags (substring suffix 3))
+	 (flags-as-list (append flags nil))
+	 (new-flags
+	  (concat (gnus-delete-duplicates
+		   ;; maildir flags must be sorted
+		   (sort (cons flag flags-as-list) '<)))))
+    (concat ":2," new-flags)))
+
+(defun nnmaildir--remove-flag (flag suffix)
+  "Return a copy of SUFFIX where FLAG is cleared.
+SUFFIX should start with \":2,\"."
+  (unless (gnus-string-match-p "^:2," suffix)
+    (error "Invalid suffix `%s'" suffix))
+  (let* ((flags (substring suffix 3))
+	 (flags-as-list (append flags nil))
+	 (new-flags (concat (delq flag flags-as-list))))
+    (concat ":2," new-flags)))
+
 (defvar nnmaildir-article-file-name nil
   "*The filename of the most recently requested article.  This variable is set
 by nnmaildir-request-article.")
@@ -85,8 +133,8 @@ by nnmaildir-request-article.")
 
 ;; Variables to generate filenames of messages being delivered:
 (defvar   nnmaildir--delivery-time "")
-(defconst nnmaildir--delivery-pid  (number-to-string (emacs-pid)))
-(defvar   nnmaildir--delivery-ct   nil)
+(defconst nnmaildir--delivery-pid (concat "P" (number-to-string (emacs-pid))))
+(defvar   nnmaildir--delivery-count nil)
 
 ;; An obarry containing symbols whose names are server names and whose values
 ;; are servers:
@@ -99,7 +147,7 @@ by nnmaildir-request-article.")
 
 ;; A NOV structure looks like this (must be prin1-able, so no defstruct):
 ["subject\tfrom\tdate"
- "references\tchars\lines"
+ "references\tchars\tlines"
  "To: you\tIn-Reply-To: <your.mess@ge>"
  (12345 67890)     ;; modtime of the corresponding article file
  (to in-reply-to)] ;; contemporary value of nnmail-extra-headers
@@ -139,17 +187,27 @@ by nnmaildir-request-article.")
 					; ("Mark Mod Time Hash")
 
 (defstruct nnmaildir--srv
-  (address    nil :type string)         ;; server address string
-  (method     nil :type list)           ;; (nnmaildir "address" ...)
-  (prefix     nil :type string)         ;; "nnmaildir+address:"
-  (dir        nil :type string)         ;; "/expanded/path/to/server/dir/"
-  (ls         nil :type function)       ;; directory-files function
-  (groups     nil :type vector)         ;; obarray mapping group names->groups
-  (curgrp     nil :type nnmaildir--grp) ;; current group, or nil
-  (error      nil :type string)         ;; last error message, or nil
-  (mtime      nil :type list)           ;; modtime of dir
-  (gnm        nil)                      ;; flag: split from mail-sources?
-  (create-dir nil :type string))        ;; group creation directory
+  (address    	 nil :type string)         ;; server address string
+  (method     	 nil :type list)           ;; (nnmaildir "address" ...)
+  (prefix     	 nil :type string)         ;; "nnmaildir+address:"
+  (dir        	 nil :type string)         ;; "/expanded/path/to/server/dir/"
+  (ls         	 nil :type function)       ;; directory-files function
+  (groups     	 nil :type vector)         ;; obarray mapping group name->group
+  (curgrp     	 nil :type nnmaildir--grp) ;; current group, or nil
+  (error      	 nil :type string)         ;; last error message, or nil
+  (mtime      	 nil :type list)           ;; modtime of dir
+  (gnm        	 nil)                      ;; flag: split from mail-sources?
+  (target-prefix nil :type string))        ;; symlink target prefix
+
+(defun nnmaildir--article-set-flags (article new-suffix curdir)
+  (let* ((prefix (nnmaildir--art-prefix article))
+	 (suffix (nnmaildir--art-suffix article))
+	 (article-file (concat curdir prefix suffix))
+	 (new-name (concat curdir prefix new-suffix)))
+    (unless (file-exists-p article-file)
+      (error "Couldn't find article file %s" article-file))
+    (rename-file article-file new-name 'replace)
+    (setf (nnmaildir--art-suffix article) new-suffix)))
 
 (defun nnmaildir--expired-article (group article)
   (setf (nnmaildir--art-nov article) nil)
@@ -207,34 +265,33 @@ by nnmaildir-request-article.")
   (eval param))
 
 (defmacro nnmaildir--with-nntp-buffer (&rest body)
-  `(save-excursion
-     (set-buffer nntp-server-buffer)
+  (declare (debug (body)))
+  `(with-current-buffer nntp-server-buffer
      ,@body))
 (defmacro nnmaildir--with-work-buffer (&rest body)
-  `(save-excursion
-     (set-buffer (get-buffer-create " *nnmaildir work*"))
+  (declare (debug (body)))
+  `(with-current-buffer (get-buffer-create " *nnmaildir work*")
      ,@body))
 (defmacro nnmaildir--with-nov-buffer (&rest body)
-  `(save-excursion
-     (set-buffer (get-buffer-create " *nnmaildir nov*"))
+  (declare (debug (body)))
+  `(with-current-buffer (get-buffer-create " *nnmaildir nov*")
      ,@body))
 (defmacro nnmaildir--with-move-buffer (&rest body)
-  `(save-excursion
-     (set-buffer (get-buffer-create " *nnmaildir move*"))
+  (declare (debug (body)))
+  `(with-current-buffer (get-buffer-create " *nnmaildir move*")
      ,@body))
 
-(defmacro nnmaildir--subdir (dir subdir)
-  `(file-name-as-directory (concat ,dir ,subdir)))
-(defmacro nnmaildir--srvgrp-dir (srv-dir gname)
-  `(nnmaildir--subdir ,srv-dir ,gname))
-(defmacro nnmaildir--tmp       (dir) `(nnmaildir--subdir ,dir "tmp"))
-(defmacro nnmaildir--new       (dir) `(nnmaildir--subdir ,dir "new"))
-(defmacro nnmaildir--cur       (dir) `(nnmaildir--subdir ,dir "cur"))
-(defmacro nnmaildir--nndir     (dir) `(nnmaildir--subdir ,dir ".nnmaildir"))
-(defmacro nnmaildir--nov-dir   (dir) `(nnmaildir--subdir ,dir "nov"))
-(defmacro nnmaildir--marks-dir (dir) `(nnmaildir--subdir ,dir "marks"))
-(defmacro nnmaildir--num-dir   (dir) `(nnmaildir--subdir ,dir "num"))
-(defmacro nnmaildir--num-file  (dir) `(concat ,dir ":"))
+(defsubst nnmaildir--subdir (dir subdir)
+  (file-name-as-directory (concat dir subdir)))
+(defsubst nnmaildir--srvgrp-dir (srv-dir gname)
+  (nnmaildir--subdir srv-dir gname))
+(defsubst nnmaildir--tmp       (dir) (nnmaildir--subdir dir "tmp"))
+(defsubst nnmaildir--new       (dir) (nnmaildir--subdir dir "new"))
+(defsubst nnmaildir--cur       (dir) (nnmaildir--subdir dir "cur"))
+(defsubst nnmaildir--nndir     (dir) (nnmaildir--subdir dir ".nnmaildir"))
+(defsubst nnmaildir--nov-dir   (dir) (nnmaildir--subdir dir "nov"))
+(defsubst nnmaildir--marks-dir (dir) (nnmaildir--subdir dir "marks"))
+(defsubst nnmaildir--num-dir   (dir) (nnmaildir--subdir dir "num"))
 
 (defmacro nnmaildir--unlink (file-arg)
   `(let ((file ,file-arg))
@@ -242,46 +299,59 @@ by nnmaildir-request-article.")
 (defun nnmaildir--mkdir (dir)
   (or (file-exists-p (file-name-as-directory dir))
       (make-directory-internal (directory-file-name dir))))
+(defun nnmaildir--mkfile (file)
+  (write-region "" nil file nil 'no-message))
 (defun nnmaildir--delete-dir-files (dir ls)
-  (mapcar 'delete-file (funcall ls dir 'full "\\`[^.]" 'nosort))
-  (delete-directory dir))
+  (when (file-attributes dir)
+    (mapc 'delete-file (funcall ls dir 'full "\\`[^.]" 'nosort))
+    (delete-directory dir)))
 
 (defun nnmaildir--group-maxnum (server group)
-  (let ((x (nnmaildir--srvgrp-dir (nnmaildir--srv-dir server)
-				  (nnmaildir--grp-name group))))
-    (setq x (nnmaildir--nndir x)
-	  x (nnmaildir--num-dir x)
-	  x (nnmaildir--num-file x)
-	  x (file-attributes x))
-    (if x (1- (nth 1 x)) 0)))
+  (catch 'return
+    (if (zerop (nnmaildir--grp-count group)) (throw 'return 0))
+    (let ((dir (nnmaildir--srvgrp-dir (nnmaildir--srv-dir server)
+				    (nnmaildir--grp-name group)))
+	  (number-opened 1)
+	  attr ino-opened nlink number-linked)
+      (setq dir (nnmaildir--nndir dir)
+	    dir (nnmaildir--num-dir dir))
+      (while t
+	(setq attr (file-attributes
+		    (concat dir (number-to-string number-opened))))
+	(or attr (throw 'return (1- number-opened)))
+	(setq ino-opened (nth 10 attr)
+	      nlink (nth 1 attr)
+	      number-linked (+ number-opened nlink))
+	(if (or (< nlink 1) (< number-linked nlink))
+	    (signal 'error '("Arithmetic overflow")))
+	(setq attr (file-attributes
+		    (concat dir (number-to-string number-linked))))
+	(or attr (throw 'return (1- number-linked)))
+	(unless (equal ino-opened (nth 10 attr))
+	  (setq number-opened number-linked))))))
 
 ;; Make the given server, if non-nil, be the current server.  Then make the
 ;; given group, if non-nil, be the current group of the current server.  Then
 ;; return the group object for the current group.
 (defun nnmaildir--prepare (server group)
-  (let (x groups)
-    (catch 'return
-      (if (null server)
-	  (unless (setq server nnmaildir--cur-server)
-	    (throw 'return nil))
-	(unless (setq server (intern-soft server nnmaildir--servers))
+  (catch 'return
+    (if (null server)
+	(unless (setq server nnmaildir--cur-server)
 	  (throw 'return nil))
-	(setq server (symbol-value server)
-	      nnmaildir--cur-server server))
-      (unless (setq groups (nnmaildir--srv-groups server))
+      (unless (setq server (intern-soft server nnmaildir--servers))
 	(throw 'return nil))
-      (unless (nnmaildir--srv-method server)
-	(setq x (concat "nnmaildir:" (nnmaildir--srv-address server))
-	      x (gnus-server-to-method x))
-	(unless x (throw 'return nil))
-	(setf (nnmaildir--srv-method server) x))
-      (if (null group)
-	  (unless (setq group (nnmaildir--srv-curgrp server))
-	    (throw 'return nil))
-	(unless (setq group (intern-soft group groups))
-	  (throw 'return nil))
-	(setq group (symbol-value group)))
-      group)))
+      (setq server (symbol-value server)
+	    nnmaildir--cur-server server))
+    (let ((groups (nnmaildir--srv-groups server)))
+      (when groups
+	(unless (nnmaildir--srv-method server)
+	  (setf (nnmaildir--srv-method server)
+		(or (gnus-server-to-method
+		     (concat "nnmaildir:" (nnmaildir--srv-address server)))
+		    (throw 'return nil))))
+	(if (null group)
+	    (nnmaildir--srv-curgrp server)
+	  (symbol-value (intern-soft group groups)))))))
 
 (defun nnmaildir--tab-to-space (string)
   (let ((pos 0))
@@ -290,12 +360,71 @@ by nnmaildir-request-article.")
       (setq pos (match-end 0))))
   string)
 
+(defmacro nnmaildir--condcase (errsym body &rest handler)
+  (declare (debug (sexp form body)))
+  `(condition-case ,errsym
+       (let ((system-messages-locale "C")) ,body)
+     (error . ,handler)))
+
+(defun nnmaildir--emlink-p (err)
+  (and (eq (car err) 'file-error)
+       (string= (downcase (caddr err)) "too many links")))
+
+(defun nnmaildir--enoent-p (err)
+  (and (eq (car err) 'file-error)
+       (string= (downcase (caddr err)) "no such file or directory")))
+
+(defun nnmaildir--eexist-p (err)
+  (eq (car err) 'file-already-exists))
+
+(defun nnmaildir--new-number (nndir)
+  "Allocate a new article number by atomically creating a file under NNDIR."
+  (let ((numdir (nnmaildir--num-dir nndir))
+	(make-new-file t)
+	(number-open 1)
+	number-link previous-number-link path-open path-link ino-open)
+    (nnmaildir--mkdir numdir)
+    (catch 'return
+      (while t
+	(setq path-open (concat numdir (number-to-string number-open)))
+	(if (not make-new-file)
+	    (setq previous-number-link number-link)
+	  (nnmaildir--mkfile path-open)
+	  ;; If Emacs had O_CREAT|O_EXCL, we could return number-open here.
+	  (setq make-new-file nil
+		previous-number-link 0))
+	(let* ((attr (file-attributes path-open))
+	       (nlink (nth 1 attr)))
+	  (setq ino-open (nth 10 attr)
+		number-link (+ number-open nlink))
+	  (if (or (< nlink 1) (< number-link nlink))
+	      (signal 'error '("Arithmetic overflow"))))
+	(if (= number-link previous-number-link)
+	    ;; We've already tried this number, in the previous loop iteration,
+	    ;; and failed.
+	    (signal 'error `("Corrupt internal nnmaildir data" ,path-open)))
+	(setq path-link (concat numdir (number-to-string number-link)))
+	(nnmaildir--condcase err
+	    (progn
+	      (add-name-to-file path-open path-link)
+	      (throw 'return number-link))
+	  (cond
+	   ((nnmaildir--emlink-p err)
+	    (setq make-new-file t
+		  number-open number-link))
+	   ((nnmaildir--eexist-p err)
+	    (let ((attr (file-attributes path-link)))
+	      (unless (equal (nth 10 attr) ino-open)
+		(setq number-open number-link
+		      number-link 0))))
+	   (t (signal (car err) (cdr err)))))))))
+
 (defun nnmaildir--update-nov (server group article)
   (let ((nnheader-file-coding-system 'binary)
 	(srv-dir (nnmaildir--srv-dir server))
 	(storage-version 1) ;; [version article-number msgid [...nov...]]
 	dir gname pgname msgdir prefix suffix file attr mtime novdir novfile
-	nov msgid nov-beg nov-mid nov-end field val old-extra num numdir
+	nov msgid nov-beg nov-mid nov-end field val old-extra num
 	deactivate-mark)
     (catch 'return
       (setq gname (nnmaildir--grp-name group)
@@ -369,8 +498,7 @@ by nnmaildir-request-article.")
 	    (setq nov-mid 0))
 	  (goto-char (point-min))
 	  (delete-char 1)
-	  (nnheader-fold-continuation-lines)
-	  (setq nov (nnheader-parse-head 'naked)
+	  (setq nov (nnheader-parse-naked-head)
 		field (or (mail-header-lines nov) 0)))
 	(unless (or (zerop field) (nnmaildir--param pgname 'distrust-Lines:))
 	  (setq nov-mid field))
@@ -388,7 +516,7 @@ by nnmaildir-request-article.")
 		nov-end (mapconcat
 			  (lambda (extra)
 			    (setq field (symbol-name (car extra))
-				  val (cdr field))
+				  val (cdr extra))
 			    (nnmaildir--tab-to-space field)
 			    (nnmaildir--tab-to-space val)
 			    (concat field ": " val))
@@ -402,37 +530,15 @@ by nnmaildir-request-article.")
 				      nnmaildir--extra)
 	      num (nnmaildir--art-num article))
 	(unless num
-	  ;; Allocate a new article number.
-	  (erase-buffer)
-	  (setq numdir (nnmaildir--num-dir dir)
-		file (nnmaildir--num-file numdir)
-		num -1)
-	  (nnmaildir--mkdir numdir)
-	  (write-region "" nil file nil 'no-message)
-	  (while file
-	    ;; Get the number of links to file.
-	    (setq attr (nth 1 (file-attributes file)))
-	    (if (= attr num)
-		;; We've already tried this number, in the previous loop
-		;; iteration, and failed.
-		(signal 'error `("Corrupt internal nnmaildir data" ,numdir)))
-	    ;; If attr is 123, try to link file to "123".  This atomically
-	    ;; increases the link count and creates the "123" link, failing
-	    ;; if that link was already created by another Gnus, just after
-	    ;; we stat()ed file.
-	    (condition-case nil
-		(progn
-		  (add-name-to-file file (concat numdir (format "%x" attr)))
-		  (setq file nil)) ;; Stop looping.
-	      (file-already-exists nil))
-	    (setq num attr))
+	  (setq num (nnmaildir--new-number dir))
 	  (setf (nnmaildir--art-num article) num))
 	;; Store this new NOV data in a file
 	(erase-buffer)
 	(prin1 (vector storage-version num msgid nov) (current-buffer))
 	(setq file (concat novfile ":"))
 	(nnmaildir--unlink file)
-	(write-region (point-min) (point-max) file nil 'no-message nil 'excl))
+	(gmm-write-region (point-min) (point-max) file nil 'no-message nil
+			  'excl))
       (rename-file file novfile 'replace)
       (setf (nnmaildir--art-msgid article) msgid)
       nov)))
@@ -453,15 +559,15 @@ by nnmaildir-request-article.")
 	count num min nlist nlist-cdr insert-nlist)
     (when nov
       (setq count (1+ (nnmaildir--grp-count group))
-	    min (nnmaildir--grp-min group)
-	    num (nnmaildir--art-num article))
-      (setq min (min min num))
-      (setq nlist (nnmaildir--grp-nlist group))
+	    num (nnmaildir--art-num article)
+	    min (if (= count 1) num
+		  (min num (nnmaildir--grp-min group)))
+	    nlist (nnmaildir--grp-nlist group))
       (if (or (null nlist) (> num (caar nlist)))
 	  (setq nlist (cons (cons num article) nlist))
 	(setq insert-nlist t
 	      nlist-cdr (cdr nlist))
-	(while (< num (caar nlist-cdr))
+	(while (and nlist-cdr (< num (caar nlist-cdr)))
 	  (setq nlist nlist-cdr
 		nlist-cdr (cdr nlist))))
       (let ((inhibit-quit t))
@@ -549,7 +655,16 @@ by nnmaildir-request-article.")
 (defun nnmaildir--up2-1 (n)
   (if (zerop n) 1 (1- (lsh 1 (1+ (logb n))))))
 
-(defun nnmaildir-request-type (group &optional article)
+(defun nnmaildir--system-name ()
+  (gnus-replace-in-string
+   (gnus-replace-in-string
+    (gnus-replace-in-string
+     (system-name)
+     "\\\\" "\\134" 'literal)
+    "/" "\\057" 'literal)
+   ":" "\\072" 'literal))
+
+(defun nnmaildir-request-type (_group &optional _article)
   'mail)
 
 (defun nnmaildir-status-message (&optional server)
@@ -607,11 +722,20 @@ by nnmaildir-request-article.")
 	   (car x)
 	   (setf (nnmaildir--srv-gnm server) t)
 	   (require 'nnmail))
-      (setq x (assq 'create-directory defs))
-      (when x
-	(setq x (cadr x)
-	      x (eval x))
-	(setf (nnmaildir--srv-create-dir server) x))
+      (setq x (assq 'target-prefix defs))
+      (if x
+	  (progn
+	    (setq x (cadr x)
+		  x (eval x))
+	    (setf (nnmaildir--srv-target-prefix server) x))
+	(setq x (assq 'create-directory defs))
+	(if x
+	    (progn
+	      (setq x (cadr x)
+		    x (eval x)
+		    x (file-name-as-directory x))
+	      (setf (nnmaildir--srv-target-prefix server) x))
+	  (setf (nnmaildir--srv-target-prefix server) "")))
       (setf (nnmaildir--srv-groups server) (make-vector size 0))
       (setq nnmaildir--cur-server server)
       t)))
@@ -619,17 +743,13 @@ by nnmaildir-request-article.")
 (defun nnmaildir--parse-filename (file)
   (let ((prefix (car file))
 	timestamp len)
-    (if (string-match
-	 "\\`\\([0-9]+\\)\\.\\([0-9]+\\)\\(_\\([0-9]+\\)\\)?\\(\\..*\\)\\'"
-	 prefix)
+    (if (string-match "\\`\\([0-9]+\\)\\(\\..*\\)\\'" prefix)
 	(progn
 	  (setq timestamp (concat "0000" (match-string 1 prefix))
 		len (- (length timestamp) 4))
 	  (vector (string-to-number (substring timestamp 0 len))
 		  (string-to-number (substring timestamp len))
-		  (string-to-number (match-string 2 prefix))
-		  (string-to-number (or (match-string 4 prefix) "-1"))
-		  (match-string 5 prefix)
+		  (match-string 2 prefix)
 		  file))
       file)))
 
@@ -642,13 +762,9 @@ by nnmaildir-request-article.")
     (if (> (aref a 0) (aref b 0)) (throw 'return nil))
     (if (< (aref a 1) (aref b 1)) (throw 'return t))
     (if (> (aref a 1) (aref b 1)) (throw 'return nil))
-    (if (< (aref a 2) (aref b 2)) (throw 'return t))
-    (if (> (aref a 2) (aref b 2)) (throw 'return nil))
-    (if (< (aref a 3) (aref b 3)) (throw 'return t))
-    (if (> (aref a 3) (aref b 3)) (throw 'return nil))
-    (string-lessp (aref a 4) (aref b 4))))
+    (string-lessp (aref a 2) (aref b 2))))
 
-(defun nnmaildir--scan (gname scan-msgs groups method srv-dir srv-ls)
+(defun nnmaildir--scan (gname scan-msgs groups _method srv-dir srv-ls)
   (catch 'return
     (let ((36h-ago (- (car (current-time)) 2))
 	  absdir nndir tdir ndir cdir nattr cattr isnew pgname read-only ls
@@ -676,22 +792,19 @@ by nnmaildir-request-article.")
 	      group (make-nnmaildir--grp :name gname :index 0))
 	(nnmaildir--mkdir nndir)
 	(nnmaildir--mkdir (nnmaildir--nov-dir   nndir))
-	(nnmaildir--mkdir (nnmaildir--marks-dir nndir))
-	(write-region "" nil (concat nndir "markfile") nil 'no-message))
+	(nnmaildir--mkdir (nnmaildir--marks-dir nndir)))
       (setq read-only (nnmaildir--param pgname 'read-only)
 	    ls (or (nnmaildir--param pgname 'directory-files) srv-ls))
       (unless read-only
 	(setq x (nth 11 (file-attributes tdir)))
-	(unless (and (= x (nth 11 nattr)) (= x (nth 11 cattr)))
+	(unless (and (equal x (nth 11 nattr)) (equal x (nth 11 cattr)))
 	  (setf (nnmaildir--srv-error nnmaildir--cur-server)
 		(concat "Maildir spans filesystems: " absdir))
 	  (throw 'return nil))
-	(mapcar
-	 (lambda (file)
-	   (setq x (file-attributes file))
-	   (if (or (> (cadr x) 1) (< (car (nth 4 x)) 36h-ago))
-	       (delete-file file)))
-	 (funcall ls tdir 'full "\\`[^.]" 'nosort)))
+	(dolist (file (funcall ls tdir 'full "\\`[^.]" 'nosort))
+	  (setq x (file-attributes file))
+	  (if (or (> (cadr x) 1) (< (car (nth 4 x)) 36h-ago))
+	      (delete-file file))))
       (or scan-msgs
 	  isnew
 	  (throw 'return t))
@@ -700,10 +813,10 @@ by nnmaildir-request-article.")
 	  (setq nattr nil))
       (if read-only (setq dir (and (or isnew nattr) ndir))
 	(when (or isnew nattr)
-	  (mapcar
-	   (lambda (file)
-	     (rename-file (concat ndir file) (concat cdir file ":2,")))
-	   (funcall ls ndir nil "\\`[^.]" 'nosort))
+	  (dolist (file  (funcall ls ndir nil "\\`[^.]" 'nosort))
+	    (setq x (concat ndir file))
+	    (and (time-less-p (nth 5 (file-attributes x)) (current-time))
+		 (rename-file x (concat cdir (nnmaildir--ensure-suffix file)))))
 	  (setf (nnmaildir--grp-new group) nattr))
 	(setq cattr (nth 5 (file-attributes cdir)))
 	(if (equal cattr (nnmaildir--grp-cur group))
@@ -728,13 +841,23 @@ by nnmaildir-request-article.")
 		cdir (nnmaildir--marks-dir nndir)
 		ndir (nnmaildir--subdir cdir "tick")
 		cdir (nnmaildir--subdir cdir "read"))
-	  (mapcar
-	   (lambda (file)
-	     (setq file (car file))
-	     (if (or (not (file-exists-p (concat cdir file)))
-		     (file-exists-p (concat ndir file)))
-		 (setq num (1+ num))))
-	   files))
+	  (dolist (prefix-suffix files)
+	    (let ((prefix (car prefix-suffix))
+		  (suffix (cdr prefix-suffix)))
+	      ;; increase num for each unread or ticked article
+	      (when (or
+		     ;; first look for marks in suffix, if it's valid...
+		     (when (and (stringp suffix)
+				(gnus-string-prefix-p ":2," suffix))
+		       (or
+			(not (gnus-string-match-p
+			      (string (nnmaildir--mark-to-flag 'read)) suffix))
+			(gnus-string-match-p
+			 (string (nnmaildir--mark-to-flag 'tick)) suffix)))
+		     ;; then look in marks directories
+		     (not (file-exists-p (concat cdir prefix)))
+		     (file-exists-p (concat ndir prefix)))
+		(incf num)))))
 	(setf (nnmaildir--grp-cache group) (make-vector num nil))
         (let ((inhibit-quit t))
           (set (intern gname groups) group))
@@ -748,16 +871,18 @@ by nnmaildir-request-article.")
 	    files (delq nil files)
 	    files (mapcar 'nnmaildir--parse-filename files)
 	    files (sort files 'nnmaildir--sort-files))
-      (mapcar
-       (lambda (file)
-	 (setq file (if (consp file) file (aref file 5))
-	       x (make-nnmaildir--art :prefix (car file) :suffix (cdr file)))
-	 (nnmaildir--grp-add-art nnmaildir--cur-server group x))
-       files)
+      (dolist (file files)
+	(setq file (if (consp file) file (aref file 3))
+	      x (make-nnmaildir--art :prefix (car file) :suffix (cdr file)))
+	(nnmaildir--grp-add-art nnmaildir--cur-server group x))
       (if read-only (setf (nnmaildir--grp-new group) nattr)
 	(setf (nnmaildir--grp-cur group) cattr)))
     t))
 
+(defvar nnmaildir-get-new-mail)
+(defvar nnmaildir-group-alist)
+(defvar nnmaildir-active-file)
+
 (defun nnmaildir-request-scan (&optional scan-group server)
   (let ((coding-system-for-write nnheader-file-coding-system)
 	(buffer-file-coding-system nil)
@@ -765,12 +890,14 @@ by nnmaildir-request-article.")
 	(nnmaildir-get-new-mail t)
 	(nnmaildir-group-alist nil)
 	(nnmaildir-active-file nil)
-	x srv-ls srv-dir method groups group dirs grp-dir seen deactivate-mark)
+	x srv-ls srv-dir method groups target-prefix dirs seen
+	deactivate-mark)
     (nnmaildir--prepare server nil)
     (setq srv-ls (nnmaildir--srv-ls nnmaildir--cur-server)
 	  srv-dir (nnmaildir--srv-dir nnmaildir--cur-server)
 	  method (nnmaildir--srv-method nnmaildir--cur-server)
-	  groups (nnmaildir--srv-groups nnmaildir--cur-server))
+	  groups (nnmaildir--srv-groups nnmaildir--cur-server)
+	  target-prefix (nnmaildir--srv-target-prefix nnmaildir--cur-server))
     (nnmaildir--with-work-buffer
       (save-match-data
 	(if (stringp scan-group)
@@ -787,21 +914,29 @@ by nnmaildir-request-article.")
 					       method srv-dir srv-ls))
 			    groups))
 	    (setq dirs (funcall srv-ls srv-dir nil "\\`[^.]" 'nosort)
+		  dirs (if (zerop (length target-prefix))
+			   dirs
+			 (gnus-remove-if
+			  (lambda (dir)
+			    (and (>= (length dir) (length target-prefix))
+				 (string= (substring dir 0
+						     (length target-prefix))
+					  target-prefix)))
+			  dirs))
 		  seen (nnmaildir--up2-1 (length dirs))
 		  seen (make-vector seen 0))
-	    (mapcar
-	     (lambda (grp-dir)
-	       (if (nnmaildir--scan grp-dir scan-group groups method srv-dir
-				    srv-ls)
-		   (intern grp-dir seen)))
-	     dirs)
+	    (dolist (grp-dir dirs)
+	      (if (nnmaildir--scan grp-dir scan-group groups method srv-dir
+				   srv-ls)
+		  (intern grp-dir seen)))
 	    (setq x nil)
 	    (mapatoms (lambda (group)
 			(setq group (symbol-name group))
 			(unless (intern-soft group seen)
 			  (setq x (cons group x))))
 		      groups)
-	    (mapcar (lambda (grp) (unintern grp groups)) x)
+	    (dolist (grp x)
+	      (unintern grp groups))
 	    (setf (nnmaildir--srv-mtime nnmaildir--cur-server)
 		  (nth 5 (file-attributes srv-dir))))
 	  (and scan-group
@@ -820,7 +955,9 @@ by nnmaildir-request-article.")
 			pgname (nnmaildir--pgname nnmaildir--cur-server pgname)
 			group (symbol-value group)
 			ro (nnmaildir--param pgname 'read-only))
-		  (insert (nnmaildir--grp-name group) " ")
+		  (insert (gnus-replace-in-string
+			   (nnmaildir--grp-name group) " " "\\ " t)
+			  " ")
                   (princ (nnmaildir--group-maxnum nnmaildir--cur-server group)
 			 nntp-server-buffer)
 		  (insert " ")
@@ -829,7 +966,7 @@ by nnmaildir-request-article.")
 		(nnmaildir--srv-groups nnmaildir--cur-server))))
   t)
 
-(defun nnmaildir-request-newgroups (date &optional server)
+(defun nnmaildir-request-newgroups (_date &optional server)
   (nnmaildir-request-list server))
 
 (defun nnmaildir-retrieve-groups (groups &optional server)
@@ -837,26 +974,30 @@ by nnmaildir-request-article.")
     (nnmaildir--prepare server nil)
     (nnmaildir--with-nntp-buffer
       (erase-buffer)
-      (mapcar
-       (lambda (gname)
-	 (setq group (nnmaildir--prepare nil gname))
-	 (if (null group) (insert "411 no such news group\n")
-	   (insert "211 ")
-	   (princ (nnmaildir--grp-count group) nntp-server-buffer)
-	   (insert " ")
-	   (princ (nnmaildir--grp-min   group) nntp-server-buffer)
-	   (insert " ")
-	   (princ (nnmaildir--group-maxnum nnmaildir--cur-server group)
-		  nntp-server-buffer)
-	   (insert " " gname "\n")))
-       groups)))
+      (dolist (gname groups)
+	(setq group (nnmaildir--prepare nil gname))
+	(if (null group) (insert "411 no such news group\n")
+	  (insert "211 ")
+	  (princ (nnmaildir--grp-count group) nntp-server-buffer)
+	  (insert " ")
+	  (princ (nnmaildir--grp-min   group) nntp-server-buffer)
+	  (insert " ")
+	  (princ (nnmaildir--group-maxnum nnmaildir--cur-server group)
+		 nntp-server-buffer)
+	  (insert " "
+		  (gnus-replace-in-string gname " " "\\ " t)
+		  "\n")))))
   'group)
 
 (defun nnmaildir-request-update-info (gname info &optional server)
-  (let ((group (nnmaildir--prepare server gname))
-	pgname flist all always-marks never-marks old-marks dotfile num dir
-	markdirs marks mark ranges markdir article read end new-marks ls
-	old-mmth new-mmth mtime mark-sym deactivate-mark)
+  (let* ((group (nnmaildir--prepare server gname))
+	 (curdir (nnmaildir--cur
+		  (nnmaildir--srvgrp-dir
+		   (nnmaildir--srv-dir nnmaildir--cur-server) gname)))
+	 (curdir-mtime (nth 5 (file-attributes curdir)))
+	 pgname flist always-marks never-marks old-marks dir
+	 all-marks marks ranges markdir read ls
+	 old-mmth new-mmth mtime existing missing deactivate-mark)
     (catch 'return
       (unless group
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
@@ -873,66 +1014,101 @@ by nnmaildir-request-article.")
 	    old-marks (cons old-marks (gnus-info-marks info))
 	    always-marks (nnmaildir--param pgname 'always-marks)
 	    never-marks (nnmaildir--param pgname 'never-marks)
+	    existing (nnmaildir--grp-nlist group)
+	    existing (mapcar 'car existing)
+	    existing (nreverse existing)
+	    existing (gnus-compress-sequence existing 'always-list)
+	    missing (list (cons 1 (nnmaildir--group-maxnum
+				   nnmaildir--cur-server group)))
+	    missing (gnus-range-difference missing existing)
 	    dir (nnmaildir--srv-dir nnmaildir--cur-server)
 	    dir (nnmaildir--srvgrp-dir dir gname)
 	    dir (nnmaildir--nndir dir)
 	    dir (nnmaildir--marks-dir dir)
             ls (nnmaildir--group-ls nnmaildir--cur-server pgname)
-	    markdirs (funcall ls dir nil "\\`[^.]" 'nosort)
-	    new-mmth (nnmaildir--up2-1 (length markdirs))
+	    all-marks (gnus-delete-duplicates
+		       ;; get mark names from mark dirs and from flag
+		       ;; mappings
+		       (append
+			(mapcar 'cdr nnmaildir-flag-mark-mapping)
+			(mapcar 'intern (funcall ls dir nil "\\`[^.]" 'nosort))))
+	    new-mmth (nnmaildir--up2-1 (length all-marks))
 	    new-mmth (make-vector new-mmth 0)
 	    old-mmth (nnmaildir--grp-mmth group))
-      (mapcar
-       (lambda (mark)
-	 (setq markdir (nnmaildir--subdir dir mark)
-	       mark-sym (intern mark)
-	       ranges nil)
-	 (catch 'got-ranges
-	   (if (memq mark-sym never-marks) (throw 'got-ranges nil))
-	   (when (memq mark-sym always-marks)
-	     (unless all
-	       (setq all (nnmaildir--grp-nlist group)
-		     all (mapcar 'car all)
-		     all (nreverse all)
-		     all (gnus-compress-sequence all 'always-list)
-		     all (cons 'dummy-mark-symbol all)))
-	     (setq ranges (cdr all))
-	     (throw 'got-ranges nil))
-	   (setq mtime (nth 5 (file-attributes markdir)))
-	   (set (intern mark new-mmth) mtime)
-	   (when (equal mtime (symbol-value (intern-soft mark old-mmth)))
-	     (setq ranges (assq mark-sym old-marks))
-	     (if ranges (setq ranges (cdr ranges)))
-	     (throw 'got-ranges nil))
-	   (mapcar
-	    (lambda (prefix)
-	      (setq article (nnmaildir--flist-art flist prefix))
-	      (if article
-		  (setq ranges
-			(gnus-add-to-range ranges
-					   `(,(nnmaildir--art-num article))))))
-	    (funcall ls markdir nil "\\`[^.]" 'nosort)))
-	 (if (eq mark-sym 'read) (setq read ranges)
-	   (if ranges (setq marks (cons (cons mark-sym ranges) marks)))))
-       markdirs)
-      (gnus-info-set-read info read)
+      (dolist (mark all-marks)
+	(setq markdir (nnmaildir--subdir dir (symbol-name mark))
+	      ranges nil)
+	(catch 'got-ranges
+	  (if (memq mark never-marks) (throw 'got-ranges nil))
+	  (when (memq mark always-marks)
+	    (setq ranges existing)
+	    (throw 'got-ranges nil))
+	  ;; Find the mtime for this mark.  If this mark can be expressed as
+	  ;; a filename flag, get the later of the mtimes for markdir and
+	  ;; curdir, otherwise only the markdir counts.
+	  (setq mtime
+		(let ((markdir-mtime (nth 5 (file-attributes markdir))))
+		  (cond
+		   ((null (nnmaildir--mark-to-flag mark))
+		    markdir-mtime)
+		   ((null markdir-mtime)
+		    curdir-mtime)
+		   ((null curdir-mtime)
+		    ;; this should never happen...
+		    markdir-mtime)
+		   ((time-less-p markdir-mtime curdir-mtime)
+		    curdir-mtime)
+		   (t
+		    markdir-mtime))))
+	  (set (intern (symbol-name mark) new-mmth) mtime)
+	  (when (equal mtime (symbol-value (intern-soft (symbol-name mark) old-mmth)))
+	    (setq ranges (assq mark old-marks))
+	    (if ranges (setq ranges (cdr ranges)))
+	    (throw 'got-ranges nil))
+	  (let ((article-list nil))
+	    ;; Consider the article marked if it either has the flag in the
+	    ;; filename, or is in the markdir.  As you'd rarely remove a
+	    ;; flag/mark, this should avoid losing information in the most
+	    ;; common usage pattern.
+	    (or
+	     (let ((flag (nnmaildir--mark-to-flag mark)))
+	       ;; If this mark has a corresponding maildir flag...
+	       (when flag
+		 (let ((regexp
+			(concat "\\`[^.].*:2,[A-Z]*" (string flag))))
+		   ;; ...then find all files with that flag.
+		   (dolist (filename (funcall ls curdir nil regexp 'nosort))
+		     (let* ((prefix (car (split-string filename ":2,")))
+			    (article (nnmaildir--flist-art flist prefix)))
+		       (when article
+			 (push (nnmaildir--art-num article) article-list)))))))
+	     ;; Also check Gnus-specific mark directory, if it exists.
+	     (when (file-directory-p markdir)
+	       (dolist (prefix (funcall ls markdir nil "\\`[^.]" 'nosort))
+		 (let ((article (nnmaildir--flist-art flist prefix)))
+		   (when article
+		     (push (nnmaildir--art-num article) article-list))))))
+	    (setq ranges (gnus-add-to-range ranges (sort article-list '<)))))
+	(if (eq mark 'read) (setq read ranges)
+	  (if ranges (setq marks (cons (cons mark ranges) marks)))))
+      (gnus-info-set-read info (gnus-range-add read missing))
       (gnus-info-set-marks info marks 'extend)
       (setf (nnmaildir--grp-mmth group) new-mmth)
       info)))
 
-(defun nnmaildir-request-group (gname &optional server fast)
+(defun nnmaildir-request-group (gname &optional server fast _info)
   (let ((group (nnmaildir--prepare server gname))
 	deactivate-mark)
-    (nnmaildir--with-nntp-buffer
-      (erase-buffer)
-      (catch 'return
-	(unless group
-	  (insert "411 no such news group\n")
-	  (setf (nnmaildir--srv-error nnmaildir--cur-server)
-		(concat "No such group: " gname))
-	  (throw 'return nil))
-	(setf (nnmaildir--srv-curgrp nnmaildir--cur-server) group)
-	(if fast (throw 'return t))
+    (catch 'return
+      (unless group
+	;; (insert "411 no such news group\n")
+	(setf (nnmaildir--srv-error nnmaildir--cur-server)
+	      (concat "No such group: " gname))
+	(throw 'return nil))
+      (setf (nnmaildir--srv-curgrp nnmaildir--cur-server) group)
+      (if fast (throw 'return t))
+      (nnmaildir--with-nntp-buffer
+	(erase-buffer)
 	(insert "211 ")
 	(princ (nnmaildir--grp-count group) nntp-server-buffer)
 	(insert " ")
@@ -940,13 +1116,13 @@ by nnmaildir-request-article.")
 	(insert " ")
 	(princ (nnmaildir--group-maxnum nnmaildir--cur-server group)
 	       nntp-server-buffer)
-	(insert " " gname "\n")
+	(insert " " (gnus-replace-in-string gname " " "\\ " t) "\n")
 	t))))
 
-(defun nnmaildir-request-create-group (gname &optional server args)
+(defun nnmaildir-request-create-group (gname &optional server _args)
   (nnmaildir--prepare server nil)
   (catch 'return
-    (let ((create-dir (nnmaildir--srv-create-dir nnmaildir--cur-server))
+    (let ((target-prefix (nnmaildir--srv-target-prefix nnmaildir--cur-server))
 	  srv-dir dir groups)
       (when (zerop (length gname))
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
@@ -958,7 +1134,7 @@ by nnmaildir-request-article.")
 	(throw 'return nil))
       (when (save-match-data (string-match "[\0/\t]" gname))
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
-	      (concat "Illegal characters (null, tab, or /) in group name: "
+	      (concat "Invalid characters (null, tab, or /) in group name: "
 		      gname))
 	(throw 'return nil))
       (setq groups (nnmaildir--srv-groups nnmaildir--cur-server))
@@ -967,18 +1143,19 @@ by nnmaildir-request-article.")
 	      (concat "Group already exists: " gname))
 	(throw 'return nil))
       (setq srv-dir (nnmaildir--srv-dir nnmaildir--cur-server))
-      (if (file-name-absolute-p create-dir)
-	  (setq dir (expand-file-name create-dir))
+      (if (file-name-absolute-p target-prefix)
+	  (setq dir (expand-file-name target-prefix))
 	(setq dir srv-dir
 	      dir (file-truename dir)
-	      dir (concat dir create-dir)))
-      (setq dir (nnmaildir--subdir (file-name-as-directory dir) gname))
+	      dir (concat dir target-prefix)))
+      (setq dir (nnmaildir--subdir dir gname))
       (nnmaildir--mkdir dir)
       (nnmaildir--mkdir (nnmaildir--tmp dir))
       (nnmaildir--mkdir (nnmaildir--new dir))
       (nnmaildir--mkdir (nnmaildir--cur dir))
-      (setq create-dir (file-name-as-directory create-dir))
-      (make-symbolic-link (concat create-dir gname) (concat srv-dir gname))
+      (unless (string= target-prefix "")
+	(make-symbolic-link (concat target-prefix gname)
+			    (concat srv-dir gname)))
       (nnmaildir-request-scan 'find-new-groups))))
 
 (defun nnmaildir-request-rename-group (gname new-name &optional server)
@@ -1002,7 +1179,7 @@ by nnmaildir-request-article.")
 	(throw 'return nil))
       (when (save-match-data (string-match "[\0/\t]" new-name))
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
-	      (concat "Illegal characters (null, tab, or /) in group name: "
+	      (concat "Invalid characters (null, tab, or /) in group name: "
 		      new-name))
 	(throw 'return nil))
       (if (string-equal gname new-name) (throw 'return t))
@@ -1034,20 +1211,28 @@ by nnmaildir-request-article.")
 
 (defun nnmaildir-request-delete-group (gname force &optional server)
   (let ((group (nnmaildir--prepare server gname))
-	pgname grp-dir dir ls deactivate-mark)
+	pgname grp-dir target dir ls deactivate-mark)
     (catch 'return
       (unless group
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
 	      (concat "No such group: " gname))
 	(throw 'return nil))
+      (setq gname (nnmaildir--grp-name group)
+	    pgname (nnmaildir--pgname nnmaildir--cur-server gname)
+	    grp-dir (nnmaildir--srv-dir nnmaildir--cur-server)
+	    target (car (file-attributes (concat grp-dir gname)))
+	    grp-dir (nnmaildir--srvgrp-dir grp-dir gname))
+      (unless (or force (stringp target))
+	(setf (nnmaildir--srv-error nnmaildir--cur-server)
+	      (concat "Not a symlink: " gname))
+	(throw 'return nil))
       (if (eq group (nnmaildir--srv-curgrp nnmaildir--cur-server))
 	  (setf (nnmaildir--srv-curgrp nnmaildir--cur-server) nil))
-      (setq gname (nnmaildir--grp-name group)
-	    pgname (nnmaildir--pgname nnmaildir--cur-server gname))
       (unintern gname (nnmaildir--srv-groups nnmaildir--cur-server))
-      (setq grp-dir (nnmaildir--srv-dir nnmaildir--cur-server)
-	    grp-dir (nnmaildir--srvgrp-dir grp-dir gname))
-      (if (not force) (setq grp-dir (directory-file-name grp-dir))
+      (if (not force)
+	  (progn
+	    (setq grp-dir (directory-file-name grp-dir))
+	    (nnmaildir--unlink grp-dir))
 	(setq ls (nnmaildir--group-ls nnmaildir--cur-server pgname))
 	(if (nnmaildir--param pgname 'read-only)
 	    (progn (delete-directory  (nnmaildir--tmp grp-dir))
@@ -1057,28 +1242,30 @@ by nnmaildir-request-article.")
 	  (nnmaildir--delete-dir-files (nnmaildir--new grp-dir) ls)
 	  (nnmaildir--delete-dir-files (nnmaildir--cur grp-dir) ls))
 	(setq dir (nnmaildir--nndir grp-dir))
-	(mapcar (lambda (subdir) (nnmaildir--delete-dir-files subdir ls))
-		`(,(nnmaildir--nov-dir dir) ,(nnmaildir--num-dir dir)
-		  ,@(funcall ls (nnmaildir--marks-dir dir) 'full "\\`[^.]"
-			     'nosort)))
+	(dolist (subdir `(,(nnmaildir--nov-dir dir) ,(nnmaildir--num-dir dir)
+			  ,@(funcall ls (nnmaildir--marks-dir dir)
+				     'full "\\`[^.]" 'nosort)))
+	  (nnmaildir--delete-dir-files subdir ls))
 	(setq dir (nnmaildir--nndir grp-dir))
 	(nnmaildir--unlink (concat dir "markfile"))
 	(nnmaildir--unlink (concat dir "markfile{new}"))
 	(delete-directory (nnmaildir--marks-dir dir))
 	(delete-directory dir)
-	(setq grp-dir (directory-file-name grp-dir)
-	      dir (car (file-attributes grp-dir)))
-	(unless (eq (aref "/" 0) (aref dir 0))
-	  (setq dir (concat (file-truename
-			     (nnmaildir--srv-dir nnmaildir--cur-server))
-			    dir)))
-	(delete-directory dir))
-      (nnmaildir--unlink grp-dir)
+	(if (not (stringp target))
+	    (delete-directory grp-dir)
+	  (setq grp-dir (directory-file-name grp-dir)
+		dir target)
+	  (unless (eq (aref "/" 0) (aref dir 0))
+	    (setq dir (concat (file-truename
+			       (nnmaildir--srv-dir nnmaildir--cur-server))
+			      dir)))
+	  (delete-directory dir)
+	  (nnmaildir--unlink grp-dir)))
       t)))
 
 (defun nnmaildir-retrieve-headers (articles &optional gname server fetch-old)
   (let ((group (nnmaildir--prepare server gname))
-	srv-dir dir nlist mlist article num start stop nov nlist2 insert-nov
+	nlist mlist article num start stop nov insert-nov
 	deactivate-mark)
     (setq insert-nov
 	  (lambda (article)
@@ -1091,7 +1278,7 @@ by nnmaildir-request-article.")
 	      (insert "\t" (nnmaildir--nov-get-beg nov) "\t"
 		      (nnmaildir--art-msgid article) "\t"
 		      (nnmaildir--nov-get-mid nov) "\tXref: nnmaildir "
-		      gname ":")
+		      (gnus-replace-in-string gname " " "\\ " t) ":")
 	      (princ num nntp-server-buffer)
 	      (insert "\t" (nnmaildir--nov-get-end nov) "\n"))))
     (catch 'return
@@ -1103,20 +1290,16 @@ by nnmaildir-request-article.")
 	(erase-buffer)
 	(setq mlist (nnmaildir--grp-mlist group)
 	      nlist (nnmaildir--grp-nlist group)
-	      gname (nnmaildir--grp-name group)
-	      srv-dir (nnmaildir--srv-dir nnmaildir--cur-server)
-	      dir (nnmaildir--srvgrp-dir srv-dir gname))
+	      gname (nnmaildir--grp-name group))
 	(cond
 	 ((null nlist))
 	 ((and fetch-old (not (numberp fetch-old)))
 	  (nnmaildir--nlist-iterate nlist 'all insert-nov))
 	 ((null articles))
 	 ((stringp (car articles))
-	  (mapcar
-	   (lambda (msgid)
-	     (setq article (nnmaildir--mlist-art mlist msgid))
-	     (if article (funcall insert-nov article)))
-	   articles))
+	  (dolist (msgid articles)
+	    (setq article (nnmaildir--mlist-art mlist msgid))
+	    (if article (funcall insert-nov article))))
 	 (t
 	  (if fetch-old
 	      ;; Assume the article range list is sorted ascending
@@ -1173,13 +1356,12 @@ by nnmaildir-request-article.")
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
 	      "Article has expired")
 	(throw 'return nil))
-      (save-excursion
-	(set-buffer (or to-buffer nntp-server-buffer))
+      (with-current-buffer (or to-buffer nntp-server-buffer)
 	(erase-buffer)
 	(nnheader-insert-file-contents nnmaildir-article-file-name))
       (cons gname num-msgid))))
 
-(defun nnmaildir-request-post (&optional server)
+(defun nnmaildir-request-post (&optional _server)
   (let (message-required-mail-headers)
     (funcall message-send-mail-function)))
 
@@ -1213,16 +1395,15 @@ by nnmaildir-request-article.")
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
 	      (concat "File exists: " tmpfile))
 	(throw 'return nil))
-      (save-excursion
-	(set-buffer buffer)
-	(write-region (point-min) (point-max) tmpfile nil 'no-message nil
-		      'excl))
+      (with-current-buffer buffer
+	(gmm-write-region (point-min) (point-max) tmpfile nil 'no-message nil
+			  'excl))
       (unix-sync) ;; no fsync :(
       (rename-file tmpfile (concat (nnmaildir--cur dir) file suffix) 'replace)
       t)))
 
 (defun nnmaildir-request-move-article (article gname server accept-form
-					       &optional last)
+				       &optional _last _move-is-internal)
   (let ((group (nnmaildir--prepare server gname))
 	pgname suffix result nnmaildir--file deactivate-mark)
     (catch 'return
@@ -1259,12 +1440,12 @@ by nnmaildir-request-article.")
 	(nnmaildir--expired-article group article))
       result)))
 
-(defun nnmaildir-request-accept-article (gname &optional server last)
+(defun nnmaildir-request-accept-article (gname &optional server _last)
   (let ((group (nnmaildir--prepare server gname))
 	(coding-system-for-write nnheader-file-coding-system)
 	(buffer-file-coding-system nil)
 	(file-coding-system-alist nil)
-	srv-dir dir file tmpfile curfile 24h article)
+	srv-dir dir file time tmpfile curfile 24h article)
     (catch 'return
       (unless group
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
@@ -1278,15 +1459,17 @@ by nnmaildir-request-article.")
 	(throw 'return nil))
       (setq srv-dir (nnmaildir--srv-dir nnmaildir--cur-server)
 	    dir (nnmaildir--srvgrp-dir srv-dir gname)
-	    file (format-time-string "%s" nil))
+	    time (current-time)
+	    file (format-time-string "%s." time))
       (unless (string-equal nnmaildir--delivery-time file)
 	(setq nnmaildir--delivery-time file
-	      nnmaildir--delivery-ct 0))
-      (setq file (concat file "." nnmaildir--delivery-pid))
-      (unless (zerop nnmaildir--delivery-ct)
-	(setq file (concat file "_"
-			   (number-to-string nnmaildir--delivery-ct))))
-      (setq file (concat file "." (system-name))
+	      nnmaildir--delivery-count 0))
+      (when (and (consp (cdr time))
+		 (consp (cddr time)))
+	(setq file (concat file "M" (number-to-string (caddr time)))))
+      (setq file (concat file nnmaildir--delivery-pid)
+	    file (concat file "Q" (number-to-string nnmaildir--delivery-count))
+	    file (concat file "." (nnmaildir--system-name))
 	    tmpfile (concat (nnmaildir--tmp dir) file)
 	    curfile (concat (nnmaildir--cur dir) file ":2,"))
       (when (file-exists-p tmpfile)
@@ -1297,7 +1480,7 @@ by nnmaildir-request-article.")
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
 	      (concat "File exists: " curfile))
 	(throw 'return nil))
-      (setq nnmaildir--delivery-ct (1+ nnmaildir--delivery-ct)
+      (setq nnmaildir--delivery-count (1+ nnmaildir--delivery-count)
 	    24h (run-with-timer 86400 nil
 				(lambda ()
 				  (nnmaildir--unlink tmpfile)
@@ -1305,13 +1488,13 @@ by nnmaildir-request-article.")
 					  nnmaildir--cur-server)
 					"24-hour timer expired")
 				  (throw 'return nil))))
-      (condition-case nil
-	  (add-name-to-file nnmaildir--file tmpfile)
+      (condition-case nil (add-name-to-file nnmaildir--file tmpfile)
 	(error
-	 (write-region (point-min) (point-max) tmpfile nil 'no-message nil
-		       'excl)
-	 (unix-sync))) ;; no fsync :(
-      (cancel-timer 24h)
+	 (gmm-write-region (point-min) (point-max) tmpfile nil 'no-message nil
+			   'excl)
+	 (when (fboundp 'unix-sync)
+	   (unix-sync)))) ;; no fsync :(
+      (nnheader-cancel-timer 24h)
       (condition-case err
 	  (add-name-to-file tmpfile curfile)
 	(error
@@ -1361,14 +1544,16 @@ by nnmaildir-request-article.")
 		    ga))
 	     group-art)))))
 
-(defun nnmaildir-active-number (gname)
+(defun nnmaildir-active-number (_gname)
   0)
 
+(declare-function gnus-group-mark-article-read "gnus-group" (group article))
+
 (defun nnmaildir-request-expire-articles (ranges &optional gname server force)
   (let ((no-force (not force))
 	(group (nnmaildir--prepare server gname))
-	pgname time boundary bound-iter high low target dir nlist nlist2
-	stop article didnt nnmaildir--file nnmaildir-article-file-name
+	pgname time boundary bound-iter high low target dir nlist
+	didnt nnmaildir--file nnmaildir-article-file-name
 	deactivate-mark)
     (catch 'return
       (unless group
@@ -1387,7 +1572,7 @@ by nnmaildir-request-article.")
 	(if (eq time 'immediate)
 	    (setq time 0)
 	  (if (numberp time)
-	      (setq time (* time 86400)))))
+	      (setq time (round (* time 86400))))))
       (when no-force
 	(unless (integerp time) ;; handle 'never
 	  (throw 'return (gnus-uncompress-range ranges)))
@@ -1436,7 +1621,12 @@ by nnmaildir-request-article.")
 			(not (string-equal target pgname))) ;; Move it.
 	       (erase-buffer)
 	       (nnheader-insert-file-contents nnmaildir--file)
-	       (gnus-request-accept-article target nil nil 'no-encode))
+	       (let ((group-art (gnus-request-accept-article
+				 target nil nil 'no-encode)))
+		 (when (consp group-art)
+		   ;; Maybe also copy: dormant forward reply save tick
+		   ;; (gnus-add-mark? gnus-request-set-mark?)
+		   (gnus-group-mark-article-read target (cdr group-art)))))
 	     (if (equal target pgname)
 		 ;; Leave it here.
 		 (setq didnt (cons (nnmaildir--art-num article) didnt))
@@ -1445,77 +1635,109 @@ by nnmaildir-request-article.")
 	(erase-buffer))
       didnt)))
 
+(defvar nnmaildir--article)
+
 (defun nnmaildir-request-set-mark (gname actions &optional server)
-  (let ((group (nnmaildir--prepare server gname))
-	(coding-system-for-write nnheader-file-coding-system)
-	(buffer-file-coding-system nil)
-	(file-coding-system-alist nil)
-	del-mark del-action add-action set-action marksdir markfile nlist
-	ranges begin end article all-marks todo-marks did-marks mdir mfile
-	pgname ls markfilenew deactivate-mark)
-    (setq del-mark
+  (let* ((group (nnmaildir--prepare server gname))
+	 (curdir (nnmaildir--cur
+		  (nnmaildir--srvgrp-dir
+		   (nnmaildir--srv-dir nnmaildir--cur-server)
+		   gname)))
+	 (coding-system-for-write nnheader-file-coding-system)
+	 (buffer-file-coding-system nil)
+	 (file-coding-system-alist nil)
+	 marksdir nlist
+	 ranges all-marks todo-marks mdir mfile
+	 pgname ls permarkfile deactivate-mark
+	 (del-mark
 	  (lambda (mark)
-	    (setq mfile (nnmaildir--subdir marksdir (symbol-name mark))
-		  mfile (concat mfile (nnmaildir--art-prefix article)))
-	    (nnmaildir--unlink mfile))
-	  del-action (lambda (article) (mapcar del-mark todo-marks))
-	  add-action
+	    (let ((prefix (nnmaildir--art-prefix nnmaildir--article))
+		  (suffix (nnmaildir--art-suffix nnmaildir--article))
+		  (flag (nnmaildir--mark-to-flag mark)))
+	      (when flag
+		;; If this mark corresponds to a flag, remove the flag from
+		;; the file name.
+		(nnmaildir--article-set-flags
+		 nnmaildir--article (nnmaildir--remove-flag flag suffix)
+		 curdir))
+	      ;; We still want to delete the hardlink in the marks dir if
+	      ;; present, regardless of whether this mark has a maildir flag or
+	      ;; not, to avoid getting out of sync.
+	      (setq mfile (nnmaildir--subdir marksdir (symbol-name mark))
+		    mfile (concat mfile prefix))
+	      (nnmaildir--unlink mfile))))
+	 (del-action (lambda (article)
+		       (let ((nnmaildir--article article))
+			 (mapcar del-mark todo-marks))))
+	 (add-action
 	  (lambda (article)
 	    (mapcar
 	     (lambda (mark)
-	       (setq mdir (nnmaildir--subdir marksdir (symbol-name mark))
-		     mfile (concat mdir (nnmaildir--art-prefix article)))
-	       (unless (memq mark did-marks)
-		 (nnmaildir--mkdir mdir)
-		 (setq did-marks (cons mark did-marks)))
-	       (unless (file-exists-p mfile)
-		 (condition-case nil
-		     (add-name-to-file markfile mfile)
-		   (file-error
-		    (unless (file-exists-p mfile)
-		      ;; too many links, maybe
-		      (write-region "" nil markfilenew nil 'no-message)
-		      (add-name-to-file markfilenew mfile
-					'ok-if-already-exists)
-		      (rename-file markfilenew markfile 'replace))))))
-	     todo-marks))
-	  set-action (lambda (article)
-		       (funcall add-action)
-		       (mapcar (lambda (mark)
-				 (unless (memq mark todo-marks)
-				   (funcall del-mark mark)))
-			       all-marks)))
+	       (let ((prefix (nnmaildir--art-prefix article))
+		     (suffix (nnmaildir--art-suffix article))
+		     (flag (nnmaildir--mark-to-flag mark)))
+		 (if flag
+		     ;; If there is a corresponding maildir flag, just rename
+		     ;; the file.
+		     (nnmaildir--article-set-flags
+		      article (nnmaildir--add-flag flag suffix) curdir)
+		   ;; Otherwise, use nnmaildir-specific marks dir.
+		   (setq mdir (nnmaildir--subdir marksdir (symbol-name mark))
+			 permarkfile (concat mdir ":")
+			 mfile (concat mdir prefix))
+		   (nnmaildir--condcase err (add-name-to-file permarkfile mfile)
+		     (cond
+		      ((nnmaildir--eexist-p err))
+		      ((nnmaildir--enoent-p err)
+		       (nnmaildir--mkdir mdir)
+		       (nnmaildir--mkfile permarkfile)
+		       (add-name-to-file permarkfile mfile))
+		      ((nnmaildir--emlink-p err)
+		       (let ((permarkfilenew (concat permarkfile "{new}")))
+			 (nnmaildir--mkfile permarkfilenew)
+			 (rename-file permarkfilenew permarkfile 'replace)
+			 (add-name-to-file permarkfile mfile)))
+		      (t (signal (car err) (cdr err))))))))
+	     todo-marks)))
+	 (set-action (lambda (article)
+		       (funcall add-action article)
+		       (let ((nnmaildir--article article))
+			 (mapcar (lambda (mark)
+				   (unless (memq mark todo-marks)
+				     (funcall del-mark mark)))
+				 all-marks)))))
     (catch 'return
       (unless group
 	(setf (nnmaildir--srv-error nnmaildir--cur-server)
 	      (concat "No such group: " gname))
-	(mapcar (lambda (action)
-		  (setq ranges (gnus-range-add ranges (car action))))
-		actions)
+	(dolist (action actions)
+	  (setq ranges (gnus-range-add ranges (car action))))
 	(throw 'return ranges))
       (setq nlist (nnmaildir--grp-nlist group)
 	    marksdir (nnmaildir--srv-dir nnmaildir--cur-server)
 	    marksdir (nnmaildir--srvgrp-dir marksdir gname)
 	    marksdir (nnmaildir--nndir marksdir)
-	    markfile (concat marksdir "markfile")
-	    markfilenew (concat markfile "{new}")
 	    marksdir (nnmaildir--marks-dir marksdir)
 	    gname (nnmaildir--grp-name group)
             pgname (nnmaildir--pgname nnmaildir--cur-server gname)
             ls (nnmaildir--group-ls nnmaildir--cur-server pgname)
 	    all-marks (funcall ls marksdir nil "\\`[^.]" 'nosort)
-	    all-marks (mapcar 'intern all-marks))
-      (mapcar
-       (lambda (action)
-	 (setq ranges (car action)
-	       todo-marks (caddr action))
-	 (mapcar (lambda (mark) (add-to-list 'all-marks mark)) todo-marks)
-	 (if (numberp (cdr ranges)) (setq ranges (list ranges)))
-	 (nnmaildir--nlist-iterate nlist ranges
-				   (cond ((eq 'del (cadr action)) del-action)
-					 ((eq 'add (cadr action)) add-action)
-					 (t set-action))))
-       actions)
+	    all-marks (gnus-delete-duplicates
+		       ;; get mark names from mark dirs and from flag
+		       ;; mappings
+		       (append
+			(mapcar 'cdr nnmaildir-flag-mark-mapping)
+			(mapcar 'intern all-marks))))
+      (dolist (action actions)
+	(setq ranges (car action)
+	      todo-marks (caddr action))
+	(dolist (mark todo-marks)
+	  (pushnew mark all-marks :test #'equal))
+	(if (numberp (cdr ranges)) (setq ranges (list ranges)))
+	(nnmaildir--nlist-iterate nlist ranges
+				  (cond ((eq 'del (cadr action)) del-action)
+					((eq 'add (cadr action)) add-action)
+					((eq 'set (cadr action)) set-action))))
       nil)))
 
 (defun nnmaildir-close-group (gname &optional server)
@@ -1544,25 +1766,21 @@ by nnmaildir-request-article.")
 	    flist (nnmaildir--up2-1 (length files))
 	    flist (make-vector flist 0))
       (save-match-data
-	(mapcar
-	 (lambda (file)
-	   (string-match "\\`\\([^:]*\\)\\(:.*\\)?\\'" file)
-	   (intern (match-string 1 file) flist))
-	 files))
-      (mapcar
-       (lambda (dir)
-	 (setq files (cdr dir)
-	       dir (file-name-as-directory (car dir)))
-	 (mapcar
-	  (lambda (file)
-	    (unless (intern-soft file flist)
-	      (setq file (concat dir file))
-	      (delete-file file)))
-	  files))
-       dirs)
+	(dolist (file files)
+	  (string-match "\\`\\([^:]*\\)\\(:.*\\)?\\'" file)
+	  (intern (match-string 1 file) flist)))
+      (dolist (dir dirs)
+	(setq files (cdr dir)
+	      dir (file-name-as-directory (car dir)))
+	(dolist (file files)
+	  (unless (or (intern-soft file flist) (string= file ":"))
+	    (setq file (concat dir file))
+	    (delete-file file))))
       t)))
 
 (defun nnmaildir-close-server (&optional server)
+  (defvar flist) (defvar ls) (defvar dirs) (defvar dir)
+  (defvar files) (defvar file) (defvar x)
   (let (flist ls dirs dir files file x)
     (nnmaildir--prepare server nil)
     (when nnmaildir--cur-server
@@ -1576,7 +1794,7 @@ by nnmaildir-request-article.")
     (mapatoms (lambda (server)
 		(setq servers (cons (symbol-name server) servers)))
 	      nnmaildir--servers)
-    (mapcar 'nnmaildir-close-server servers)
+    (mapc 'nnmaildir-close-server servers)
     (setq buffer (get-buffer " *nnmaildir work*"))
     (if buffer (kill-buffer buffer))
     (setq buffer (get-buffer " *nnmaildir nov*"))