(rmail-enable-multibyte): New variable

(rmail): Bind coding-system-for-read to raw-text.  Set the buffer
multibyte if necessary.
(rmail-convert-file): Call rmail-decode-babyl-format only when we
don't have to call rmail-convert-to-babyl-format.
(rmail-decode-babyl-format): If rmail-file-coding-system is nil,
detect it.
(rmail-get-new-mail): Bind rmail-enable-multibyte locally.
(rmail-convert-to-babyl-format): Check the value of
rmail-enable-multibyte instead of enable-multibyte-characters.

diff --git a/lisp/mail/rmail.el b/lisp/mail/rmail.el
index 0371837b6a28bd748a9ea33c133f7e97f5d26125..2eb712e9338610a18a7c85fdc1c4636a5ad2627f 100644 (file)
--- a/lisp/mail/rmail.el
+++ b/lisp/mail/rmail.el
@@ -429,6 +429,8 @@ is non-nil.")
 \f
 ;;;; *** Rmail Mode ***
 
+(defvar rmail-enable-multibyte nil)
+
 ;;;###autoload
 (defun rmail (&optional file-name-arg)
   "Read and edit incoming mail.
@@ -452,6 +454,14 @@ If `rmail-display-summary' is non-nil, make a summary for this RMAIL file."
               (setq rmail-enable-mime nil))))
   (let* ((file-name (expand-file-name (or file-name-arg rmail-file-name)))
         (existed (get-file-buffer file-name))
+        (rmail-enable-multibyte (default-value 'enable-multibyte-characters))
+        ;; Since the file may contain messages of different encodings
+        ;; at the tail (non-BYBYL part), we can't decode them at once
+        ;; on reading.  So, at first, we read the file without text
+        ;; code conversion, then decode the messages one by one by
+        ;; rmail-decode-babyl-format or
+        ;; rmail-convert-to-babyl-format.
+        (coding-system-for-read (and rmail-enable-multibyte 'raw-text))
         run-mail-hook msg-shown)
     ;; Like find-file, but in the case where a buffer existed
     ;; and the file was reverted, recompute the message-data.
@@ -478,6 +488,11 @@ If `rmail-display-summary' is non-nil, make a summary for this RMAIL file."
       (rmail-mode-2)
       ;; Convert all or part to Babyl file if possible.
       (rmail-convert-file)
+      ;; As we have read a file by raw-text, the buffer is set to
+      ;; unibyte.  We must make it multibyte if necessary.
+      (if (and rmail-enable-multibyte
+              (not enable-multibyte-characters))
+         (set-buffer-multibyte t))
       (goto-char (point-max))
       (if (null rmail-inbox-list)
          (progn
@@ -531,13 +546,6 @@ If `rmail-display-summary' is non-nil, make a summary for this RMAIL file."
           ;; Non-empty file in non-RMAIL format.  Add header and convert.
           (setq convert t)
           (rmail-insert-rmail-file-header)))
-    (if (and (not convert)
-            (not rmail-enable-mime)
-            rmail-file-coding-system)
-       ;; Decode coding system of BABYL part at the head only.  The
-       ;; remaining non BABYL parts are decoded in
-       ;; rmail-convert-to-babyl-format if necessary.
-       (rmail-decode-babyl-format))
     ;; If file was not a Babyl file or if there are
     ;; Unix format messages added at the end,
     ;; convert file as necessary.
@@ -556,7 +564,11 @@ If `rmail-display-summary' is non-nil, make a summary for this RMAIL file."
          (search-forward "\n\^_" nil t)
          (narrow-to-region (point) (point-max))
          (rmail-convert-to-babyl-format)
-         (message "Converting to Babyl format...done")))))
+         (message "Converting to Babyl format...done"))
+      (if (and (not rmail-enable-mime)
+              rmail-enable-multibyte)
+         ;; We still have to decode BABYL part.
+         (rmail-decode-babyl-format)))))
 
 ;;; I have checked that adding "-*- rmail -*-" to the BABYL OPTIONS line
 ;;; will not cause emacs 18.55 problems.
@@ -571,22 +583,34 @@ Note:   If you are seeing it in rmail,
 Note:    it means the file has no messages in it.\n\^_")))
 
 ;; Decode Babyl formated part at the head of current buffer by
-;; rmail-file-coding-system.
+;; rmail-file-coding-system, or if it is nil, do auto conversion.
 
 (defun rmail-decode-babyl-format ()
   (let ((modifiedp (buffer-modified-p))
        (buffer-read-only nil)
-       pos)
+       from to)
     (goto-char (point-min))
     (search-forward "\n\^_" nil t)     ; Skip BYBYL header.
-    (setq pos (point))
-    (message "Decoding messages...")
-    (while (search-forward "\n\^_" nil t)
-      (decode-coding-region pos (point) rmail-file-coding-system)
-      (setq pos (point)))
-    (message "Decoding messages...done")
-    (set-buffer-file-coding-system rmail-file-coding-system)
-    (set-buffer-modified-p modifiedp)))
+    (setq from (point))
+    (goto-char (point-max))
+    (search-backward "\n\^_" from 'mv)
+    (setq to (point))
+    (if (not (and rmail-file-coding-system
+                 (coding-system-p rmail-file-coding-system)))
+       (setq rmail-file-coding-system (detect-coding-region from to t)))
+    (if (not (eq rmail-file-coding-system 'undecided))
+       (let ((count 1))
+         (goto-char from)
+         (while (search-forward "\n\^_" nil t)
+           (decode-coding-region from (1- (point)) rmail-file-coding-system)
+           (goto-char (point))
+           (setq from (point))
+           (if (= (% count 10) 0)
+               (message "Decoding messages (%d)..." count))
+           (setq count (1+ count)))
+         (message "Decoding messages (%d)...done" count)
+         (set-buffer-file-coding-system rmail-file-coding-system)
+         (set-buffer-modified-p modifiedp)))))
 
 (if rmail-mode-map
     nil
@@ -1085,6 +1109,7 @@ It returns t if it got any new messages."
       (setq buffer-undo-list nil))
   (let ((all-files (if file-name (list file-name)
                     rmail-inbox-list))
+       (rmail-enable-multibyte (default-value 'enable-multibyte-characters))
        found)
     (unwind-protect
        (progn
@@ -1396,9 +1421,10 @@ Optional DEFAULT is password to start with."
                                (skip-chars-forward " \t\n")
                                (point)))
               (or rmail-enable-mime
-                  (not rmail-file-coding-system)
+                  (not rmail-enable-multibyte)
                   (decode-coding-region start (point)
-                                        rmail-file-coding-system))
+                                        (or rmail-file-coding-system
+                                            'undecided)))
               (narrow-to-region (point) (point-max)))
              ;;*** MMDF format
              ((let ((case-fold-search t))
@@ -1414,7 +1440,7 @@ Optional DEFAULT is password to start with."
                   (while (search-forward "\n\^_" nil t); single char "\^_"
                     (replace-match "\n^_")))); 2 chars: "^" and "_"
               (or rmail-enable-mime
-                  (not enable-multibyte-characters)
+                  (not rmail-enable-multibyte)
                   (decode-coding-region start (point) 'undecided))
               (narrow-to-region (point) (point-max))
               (setq count (1+ count)))
@@ -1490,7 +1516,7 @@ Optional DEFAULT is password to start with."
                     (replace-match "\n^_")))); 2 chars: "^" and "_"
               (insert ?\^_)
               (or rmail-enable-mime
-                  (not enable-multibyte-characters)
+                  (not rmail-enable-multibyte)
                   (decode-coding-region start (point) 'undecided))
               (narrow-to-region (point) (point-max)))
              ;;