Package: emacs;
Reported by: Ian Dunn <dunni <at> gnu.org>
Date: Sun, 3 Mar 2019 15:29:01 UTC
Severity: normal
Tags: confirmed, fixed
Found in version 26.1
Fixed in version 27.1
Done: Lars Ingebrigtsen <larsi <at> gnus.org>
Bug is archived. No further changes may be made.
Message #13 received at 34720 <at> debbugs.gnu.org (full text, mbox):
From: Lars Ingebrigtsen <larsi <at> gnus.org> To: Ian Dunn <dunni <at> gnu.org> Cc: 34720 <at> debbugs.gnu.org Subject: Re: bug#34720: 26.1; Reverting a GPG buffer moves all markers to the end of the file Date: Mon, 26 Aug 2019 09:20:29 +0200
Lars Ingebrigtsen <larsi <at> gnus.org> writes:
>> 1. Open a GnuPG encrypted file
>> 2. Run the following:
>> (setq test-marker (make-marker))
>> (move-marker test-marker (point-marker))
>> ;; test-marker points to `point'
>> 3. Revert the buffer
>> ;; test-marker now points to the end of the buffer
I took a stab at this with the patch below (which is the wrong solution
because it doesn't clear the undo list etc).
But I don't quite understand why this is so much work. :-)
The problem is twofold: The first is in epa.el itself, which deletes and
then inserts, which destroys the markers.
The second is the call to `decode-coding-region' in
`decode-coding-inserted-region', which also destroys the markers.
The third is that the interface to the new replace-buffer-contents
function is really awkward -- it only takes a buffer as its SOURCE,
which means that if you want to feed it something, you have to skip
around to temporary buffers instead of feeding it a string, which would
be natural. You have to be a with-temp-buffer/with-current-buffer/let
contortionist to get it to be safe.
And replace-buffer-contents does so much more than just restoring
markers, anyway, so I'm not sure it's the right solution here, anyway.
Would anybody mind if I just write a `with-saved-markers' macro in
subr-x, which would make all these problems to away and make the
solution a two-liner in epa itself?
(Unless such a macro exists somewhere already.)
diff --git a/lisp/epa-file.el b/lisp/epa-file.el
index d9886d3d67..03f53c40a9 100644
--- a/lisp/epa-file.el
+++ b/lisp/epa-file.el
@@ -24,6 +24,7 @@
(require 'epa)
(require 'epa-hook)
+(require 'mule)
(defcustom epa-file-cache-passphrase-for-symmetric-encryption nil
"If non-nil, cache passphrase for symmetric encryption.
@@ -102,16 +103,21 @@ epa-file-run-real-handler
(apply operation args)))
(defun epa-file-decode-and-insert (string file visit beg end replace)
- (if (fboundp 'decode-coding-inserted-region)
- (save-restriction
- (narrow-to-region (point) (point))
- (insert string)
- (decode-coding-inserted-region
- (point-min) (point-max)
- (substring file 0 (string-match epa-file-name-regexp file))
- visit beg end replace))
- (insert (epa-file--decode-coding-string string (or coding-system-for-read
- 'undecided)))))
+ (let ((buffer (current-buffer)))
+ (with-temp-buffer
+ (insert string)
+ (let ((coding (decode-coding-inserted-region-coding-system
+ (substring
+ file 0 (string-match epa-file-name-regexp file))
+ visit beg end replace)))
+ (if coding
+ (decode-coding-region (point-min) (point-max) coding)
+ (setq last-coding-system-used coding))
+ (let ((temp (current-buffer)))
+ (with-current-buffer buffer
+ (if replace
+ (replace-buffer-contents temp)
+ (insert-buffer-substring temp))))))))
(defvar epa-file-error nil)
(defun epa-file--find-file-not-found-function ()
@@ -147,8 +153,6 @@ epa-file-insert-file-contents
(format "Decrypting %s" file)))
(unwind-protect
(progn
- (if replace
- (goto-char (point-min)))
(condition-case error
(setq string (epg-decrypt-file context local-file nil))
(error
@@ -187,12 +191,9 @@ epa-file-insert-file-contents
;; really edit the buffer.
(let ((buffer-file-name
(if visit nil buffer-file-name)))
- (save-restriction
- (narrow-to-region (point) (point))
- (epa-file-decode-and-insert string file visit beg end replace)
- (setq length (- (point-max) (point-min))))
- (if replace
- (delete-region (point) (point-max))))
+ (setq length
+ (epa-file-decode-and-insert
+ string file visit beg end replace)))
(if visit
(set-visited-file-modtime))))
(if (and local-copy
diff --git a/lisp/international/mule.el b/lisp/international/mule.el
index ec6f647688..5338e54cf6 100644
--- a/lisp/international/mule.el
+++ b/lisp/international/mule.el
@@ -2244,6 +2244,25 @@ modify-coding-system-alist
(cons (cons regexp coding-system)
network-coding-system-alist)))))))
+(defun decode-coding-inserted-region-coding-system (filename
+ visit beg end replace)
+ "Return a coding system for the current buffer as if it is read from FILENAME."
+ (let ((coding coding-system-for-read))
+ (unless coding
+ (setq coding (funcall set-auto-coding-function
+ filename (- (point-max) (point-min)))))
+ (unless coding
+ (setq coding (car (find-operation-coding-system
+ 'insert-file-contents
+ (cons filename (current-buffer))
+ visit beg end replace))))
+ (if (coding-system-p coding)
+ (or enable-multibyte-characters
+ (setq coding
+ (coding-system-change-text-conversion coding 'raw-text)))
+ (setq coding nil))
+ coding))
+
(defun decode-coding-inserted-region (from to filename
&optional visit beg end replace)
"Decode the region between FROM and TO as if it is read from file FILENAME.
@@ -2253,8 +2272,7 @@ decode-coding-inserted-region
Part of the job of this function is setting `buffer-undo-list' appropriately."
(save-excursion
(save-restriction
- (let ((coding coding-system-for-read)
- undo-list-saved)
+ (let (coding undo-list-saved)
(if visit
;; Temporarily turn off undo recording, if we're decoding the
;; text of a visited file.
@@ -2268,19 +2286,8 @@ decode-coding-inserted-region
buffer-undo-list t))))
(narrow-to-region from to)
(goto-char (point-min))
- (or coding
- (setq coding (funcall set-auto-coding-function
- filename (- (point-max) (point-min)))))
- (or coding
- (setq coding (car (find-operation-coding-system
- 'insert-file-contents
- (cons filename (current-buffer))
- visit beg end replace))))
- (if (coding-system-p coding)
- (or enable-multibyte-characters
- (setq coding
- (coding-system-change-text-conversion coding 'raw-text)))
- (setq coding nil))
+ (setq coding (decode-coding-inserted-region-coding-system
+ filename visit beg end replace))
(if coding
(decode-coding-region (point-min) (point-max) coding)
(setq last-coding-system-used coding))
--
(domestic pets only, the antidote for overdose, milk.)
bloggy blog: http://lars.ingebrigtsen.no
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1994-97 Ian Jackson.