Bug fix for finding coding system. New COPY-FUNCTION feature

for epa-decrypt-region.

2 files changed, 26 insertions, 10 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 7116a152605..053f9d3bab6 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2011-08-16  Richard Stallman  <rms@gnu.org>
+
+        * epa.el (epa-decrypt-region): New arg COPY-FUNCTION.
+        (epa--find-coding-system-for-mime-charset): Fix the non-xemacs case.
+        (epa-decrypt-armor-in-region): Make error message clearer.
+
 2011-08-15  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * minibuffer.el (completion-pcm--merge-completions): Don't merge "a1b"
diff --git a/lisp/epa.el b/lisp/epa.el
index e2fafc753d7..5611379ea51 100644
--- a/lisp/epa.el
+++ b/lisp/epa.el
@@ -803,10 +803,12 @@ If no one is selected, symmetric encryption will be performed.  ")))
              (file-name-nondirectory cipher))))
 
 ;;;###autoload
-(defun epa-decrypt-region (start end)
+(defun epa-decrypt-region (start end &optional copy-function)
   "Decrypt the current region between START and END.
+If COPY-FUNCTION is non-nil, call it to copy the current buffer
+into some other buffer for the output; it should return that buffer.
 
-Don't use this command in Lisp programs!
+Be careful about using this command in Lisp programs!
 Since this function operates on regions, it does some tricks such
 as coding-system detection and unibyte/multibyte conversion.  If
 you are sure how the data in the region should be treated, you
@@ -844,10 +846,17 @@ For example:
             (delete-region start end)
             (goto-char start)
             (insert plain))
-        (with-output-to-temp-buffer "*Temp*"
-          (set-buffer standard-output)
-          (insert plain)
-          (epa-info-mode)))
+        (if copy-function
+            (with-current-buffer (funcall copy-function)
+              (let ((inhibit-read-only t)
+                    buffer-read-only)
+                (delete-region start end)
+                (goto-char start)
+                (insert plain)))
+          (with-output-to-temp-buffer "*Temp*"
+            (set-buffer standard-output)
+              (insert plain)
+              (epa-info-mode))))
       (if (epg-context-result-for context 'verify)
           (epa-display-info (epg-verify-result-to-string
                              (epg-context-result-for context 'verify)))))))
@@ -856,12 +865,13 @@ For example:
   (if (featurep 'xemacs)
       (if (fboundp 'find-coding-system)
           (find-coding-system mime-charset))
+    ;; Find the first coding system which corresponds to MIME-CHARSET.
     (let ((pointer (coding-system-list)))
       (while (and pointer
-                  (eq (coding-system-get (car pointer) 'mime-charset)
-                      mime-charset))
+                  (not (eq (coding-system-get (car pointer) 'mime-charset)
+                           mime-charset)))
         (setq pointer (cdr pointer)))
-      pointer)))
+      (car pointer))))
 
 ;;;###autoload
 (defun epa-decrypt-armor-in-region (start end)
@@ -880,7 +890,7 @@ See the reason described in the `epa-decrypt-region' documentation."
                 armor-end (re-search-forward "^-----END PGP MESSAGE-----$"
                                              nil t))
           (unless armor-end
-            (error "No armor tail"))
+            (error "Encryption armor beginning has no matching end"))
           (goto-char armor-start)
           (let ((coding-system-for-read
                  (or coding-system-for-read