[Emacs-diffs] trunk r118299: epg: Improve error handling

[Daiki Ueno]

------------------------------------------------------------
revno: 118299
revision-id: address@hidden
parent: address@hidden
committer: Daiki Ueno <address@hidden>
branch nick: trunk
timestamp: Thu 2014-11-06 12:04:22 +0900
message:
  epg: Improve error handling
  
  * epa.el (epa-error-buffer): New variable.
  (epa-display-error): New function.
  (epa-decrypt-file, epa-verify-file, epa-verify-region)
  (epa-delete-keys, epa-import-keys): Display output sent to stderr.
  (epa-sign-file, epa-sign-region, epa-encrypt-region)
  (epa-export-keys, epa-insert-keys): Display output sent to stderr.
  Use setf instead of epg-context-set-*.
  * epa-file.el (epa-file-insert-file-contents): Use
  epa-display-error instead of epa-display-info.  Mimic the behavior
  of jka-compr when decryption program is not found.
  (epa-file-write-region): Use epa-display-error instead of
  epa-display-info.
modified:
  lisp/ChangeLog                 changelog-20091113204419-o5vbwnq5f7feedwu-1432
  lisp/epa-file.el               epafile.el-20091113204419-o5vbwnq5f7feedwu-8554
  lisp/epa.el                    epa.el-20091113204419-o5vbwnq5f7feedwu-8557

=== modified file 'lisp/ChangeLog'
--- a/lisp/ChangeLog    2014-11-05 19:59:31 +0000
+++ b/lisp/ChangeLog    2014-11-06 03:04:22 +0000
@@ -1,3 +1,18 @@
+2014-11-06  Daiki Ueno  <address@hidden>
+
+       * epa.el (epa-error-buffer): New variable.
+       (epa-display-error): New function.
+       (epa-decrypt-file, epa-verify-file, epa-verify-region)
+       (epa-delete-keys, epa-import-keys): Display output sent to stderr.
+       (epa-sign-file, epa-sign-region, epa-encrypt-region)
+       (epa-export-keys, epa-insert-keys): Display output sent to stderr.
+       Use setf instead of epg-context-set-*.
+       * epa-file.el (epa-file-insert-file-contents): Use
+       epa-display-error instead of epa-display-info.  Mimic the behavior
+       of jka-compr when decryption program is not found.
+       (epa-file-write-region): Use epa-display-error instead of
+       epa-display-info.
+
 2014-11-05  Stefan Monnier  <address@hidden>
 
        * vc/vc.el (vc-region-history): New command.

=== modified file 'lisp/epa-file.el'
--- a/lisp/epa-file.el  2014-11-05 09:38:37 +0000
+++ b/lisp/epa-file.el  2014-11-06 03:04:22 +0000
@@ -105,9 +105,9 @@
        (insert (if enable-multibyte-characters
                    (string-to-multibyte string)
                  string))
-         (decode-coding-inserted-region
-          (point-min) (point-max)
-          (substring file 0 (string-match epa-file-name-regexp file))
+       (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)))))
@@ -151,8 +151,17 @@
          (condition-case error
              (setq string (epg-decrypt-file context local-file nil))
            (error
+            (epa-display-error context)
             (if (setq entry (assoc file epa-file-passphrase-alist))
                 (setcdr entry nil))
+            ;; If the decryption program can't be found,
+            ;; signal that as a non-file error
+            ;; so that find-file-noselect-1 won't handle it.
+            ;; Borrowed from jka-compr.el.
+            (if (and (eq (car error) 'file-error)
+                     (equal (cadr error) "Searching for program"))
+                (error "Decryption program `%s' not found"
+                       (nth 3 error)))
             ;; Hack to prevent find-file from opening empty buffer
             ;; when decryption failed (bug#6568).  See the place
             ;; where `find-file-not-found-functions' are called in
@@ -162,11 +171,6 @@
               (add-hook 'find-file-not-found-functions
                         'epa-file--find-file-not-found-function
                         nil t))
-            (if (epg-context-error-output context)
-                (epa-display-info
-                 (concat (format "Error while executing \"%s\":\n\n"
-                                 epg-gpg-program)
-                         (epg-context-error-output context))))
             (signal 'file-error
                     (cons "Opening input file" (cdr error)))))
           (set-buffer buf) ;In case timer/filter changed/killed it (bug#16029)!
@@ -226,7 +230,7 @@
      context
      (cons #'epa-progress-callback-function
           (format "Encrypting %s" file)))
-    (epg-context-set-armor context epa-armor)
+    (setf (epg-context-armor context) epa-armor)
     (condition-case error
        (setq string
              (epg-encrypt-string
@@ -260,13 +264,9 @@
                 (if epa-file-encrypt-to
                     (epg-list-keys context recipients)))))
       (error
+       (epa-display-error context)
        (if (setq entry (assoc file epa-file-passphrase-alist))
           (setcdr entry nil))
-       (if (epg-context-error-output context)
-          (epa-display-info
-           (concat (format "Error while executing \"%s\":\n\n"
-                           epg-gpg-program)
-                   (epg-context-error-output context))))
        (signal 'file-error (cons "Opening output file" (cdr error)))))
     (epa-file-run-real-handler
      #'write-region

=== modified file 'lisp/epa.el'
--- a/lisp/epa.el       2014-03-22 22:36:29 +0000
+++ b/lisp/epa.el       2014-11-06 03:04:22 +0000
@@ -166,6 +166,7 @@
 (defvar epa-key nil)
 (defvar epa-list-keys-arguments nil)
 (defvar epa-info-buffer nil)
+(defvar epa-error-buffer nil)
 (defvar epa-last-coding-system-specified nil)
 
 (defvar epa-key-list-mode-map
@@ -578,6 +579,34 @@
              (shrink-window (- (window-height) epa-info-window-height)))))
     (message "%s" info)))
 
+(defun epa-display-error (context)
+  (unless (equal (epg-context-error-output context) "")
+    (let ((buffer (get-buffer-create "*Error*")))
+      (save-selected-window
+       (unless (and epa-error-buffer (buffer-live-p epa-error-buffer))
+         (setq epa-error-buffer (generate-new-buffer "*Error*")))
+       (if (get-buffer-window epa-error-buffer)
+           (delete-window (get-buffer-window epa-error-buffer)))
+       (with-current-buffer buffer
+         (let ((inhibit-read-only t)
+               buffer-read-only)
+           (erase-buffer)
+           (insert (format
+                    (pcase (epg-context-operation context)
+                      (`decrypt "Error while decrypting with \"%s\":")
+                      (`verify "Error while verifying with \"%s\":")
+                      (`sign "Error while signing with \"%s\":")
+                      (`encrypt "Error while encrypting with \"%s\":")
+                      (`import-keys "Error while importing keys with \"%s\":")
+                      (`export-keys "Error while exporting keys with \"%s\":")
+                      (_ "Error while executing \"%s\":\n\n"))
+                    epg-gpg-program)
+                   "\n\n"
+                   (epg-context-error-output context)))
+         (epa-info-mode)
+         (goto-char (point-min)))
+       (display-buffer buffer)))))
+
 (defun epa-display-verify-result (verify-result)
   (declare (obsolete epa-display-info "23.1"))
   (epa-display-info (epg-verify-result-to-string verify-result)))
@@ -593,14 +622,14 @@
        (eq (epg-context-operation context) 'encrypt))
     (read-passwd
      (if (eq key-id 'PIN)
-       "Passphrase for PIN: "
+        "Passphrase for PIN: "
        (let ((entry (assoc key-id epg-user-id-alist)))
         (if entry
             (format "Passphrase for %s %s: " key-id (cdr entry))
           (format "Passphrase for %s: " key-id)))))))
 
 (defun epa-progress-callback-function (_context what _char current total
-                                              handback)
+                                               handback)
   (let ((prompt (or handback
                    (format "Processing %s: " what))))
     ;; According to gnupg/doc/DETAIL: a "total" of 0 indicates that
@@ -641,7 +670,11 @@
                                        (format "Decrypting %s..."
                                                (file-name-nondirectory 
decrypt-file))))
     (message "Decrypting %s..." (file-name-nondirectory decrypt-file))
-    (epg-decrypt-file context decrypt-file plain-file)
+    (condition-case error
+       (epg-decrypt-file context decrypt-file plain-file)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Decrypting %s...wrote %s" (file-name-nondirectory decrypt-file)
             (file-name-nondirectory plain-file))
     (if (epg-context-result-for context 'verify)
@@ -662,7 +695,11 @@
                                        (format "Verifying %s..."
                                                (file-name-nondirectory file))))
     (message "Verifying %s..." (file-name-nondirectory file))
-    (epg-verify-file context file plain)
+    (condition-case error
+       (epg-verify-file context file plain)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Verifying %s...done" (file-name-nondirectory file))
     (if (epg-context-result-for context 'verify)
        (epa-display-info (epg-verify-result-to-string
@@ -717,18 +754,22 @@
                                 ".p7s"
                               ".p7m"))))
        (context (epg-make-context epa-protocol)))
-    (epg-context-set-armor context epa-armor)
-    (epg-context-set-textmode context epa-textmode)
-    (epg-context-set-signers context signers)
-    (epg-context-set-passphrase-callback context
-                                        #'epa-passphrase-callback-function)
-    (epg-context-set-progress-callback context
-                                      (cons
-                                       #'epa-progress-callback-function
-                                       (format "Signing %s..."
-                                               (file-name-nondirectory file))))
+    (setf (epg-context-armor context) epa-armor)
+    (setf (epg-context-textmode context) epa-textmode)
+    (setf (epg-context-signers context) signers)
+    (setf (epg-context-passphrase-callback context)
+         #'epa-passphrase-callback-function)
+    (setf (epg-context-progress-callback context)
+         (cons
+          #'epa-progress-callback-function
+          (format "Signing %s..."
+                  (file-name-nondirectory file))))
     (message "Signing %s..." (file-name-nondirectory file))
-    (epg-sign-file context file signature mode)
+    (condition-case error
+       (epg-sign-file context file signature mode)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Signing %s...wrote %s" (file-name-nondirectory file)
             (file-name-nondirectory signature))))
 
@@ -744,17 +785,21 @@
                                 (if epa-armor ".asc" ".gpg")
                               ".p7m")))
        (context (epg-make-context epa-protocol)))
-    (epg-context-set-armor context epa-armor)
-    (epg-context-set-textmode context epa-textmode)
-    (epg-context-set-passphrase-callback context
-                                        #'epa-passphrase-callback-function)
-    (epg-context-set-progress-callback context
-                                      (cons
-                                       #'epa-progress-callback-function
-                                       (format "Encrypting %s..."
-                                               (file-name-nondirectory file))))
+    (setf (epg-context-armor context) epa-armor)
+    (setf (epg-context-textmode context) epa-textmode)
+    (setf (epg-context-passphrase-callback context)
+         #'epa-passphrase-callback-function)
+    (setf (epg-context-progress-callback context)
+         (cons
+          #'epa-progress-callback-function
+          (format "Encrypting %s..."
+                  (file-name-nondirectory file))))
     (message "Encrypting %s..." (file-name-nondirectory file))
-    (epg-encrypt-file context file recipients cipher)
+    (condition-case error
+       (epg-encrypt-file context file recipients cipher)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Encrypting %s...wrote %s" (file-name-nondirectory file)
             (file-name-nondirectory cipher))))
 
@@ -785,14 +830,18 @@
   (save-excursion
     (let ((context (epg-make-context epa-protocol))
          plain)
-      (epg-context-set-passphrase-callback context
-                                          #'epa-passphrase-callback-function)
-      (epg-context-set-progress-callback context
-                                        (cons
-                                         #'epa-progress-callback-function
-                                         "Decrypting..."))
+      (setf (epg-context-passphrase-callback context)
+           #'epa-passphrase-callback-function)
+      (setf (epg-context-progress-callback context)
+           (cons
+            #'epa-progress-callback-function
+            "Decrypting..."))
       (message "Decrypting...")
-      (setq plain (epg-decrypt-string context (buffer-substring start end)))
+      (condition-case error
+         (setq plain (epg-decrypt-string context (buffer-substring start end)))
+       (error
+        (epa-display-error context)
+        (signal (car error) (cdr error))))
       (message "Decrypting...done")
       (setq plain (epa--decode-coding-string
                   plain
@@ -810,8 +859,8 @@
              (insert plain))
          (with-output-to-temp-buffer "*Temp*"
            (set-buffer standard-output)
-             (insert plain)
-             (epa-info-mode))))
+           (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)))))))
@@ -878,17 +927,21 @@
   (interactive "r")
   (let ((context (epg-make-context epa-protocol))
        plain)
-    (epg-context-set-progress-callback context
-                                      (cons
-                                       #'epa-progress-callback-function
-                                       "Verifying..."))
+    (setf (epg-context-progress-callback context)
+         (cons
+          #'epa-progress-callback-function
+          "Verifying..."))
     (message "Verifying...")
-    (setq plain (epg-verify-string
-                context
-                (epa--encode-coding-string
-                 (buffer-substring start end)
-                 (or coding-system-for-write
-                     (get-text-property start 'epa-coding-system-used)))))
+    (condition-case error
+       (setq plain (epg-verify-string
+                    context
+                    (epa--encode-coding-string
+                     (buffer-substring start end)
+                     (or coding-system-for-write
+                         (get-text-property start 'epa-coding-system-used)))))
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Verifying...done")
     (setq plain (epa--decode-coding-string
                 plain
@@ -927,11 +980,11 @@
                                  nil t)
          (setq cleartext-start (match-beginning 0))
          (unless (re-search-forward "^-----BEGIN PGP SIGNATURE-----$"
-                                          nil t)
+                                    nil t)
            (error "Invalid cleartext signed message"))
          (setq cleartext-end (re-search-forward
-                          "^-----END PGP SIGNATURE-----$"
-                          nil t))
+                              "^-----END PGP SIGNATURE-----$"
+                              nil t))
          (unless cleartext-end
            (error "No cleartext tail"))
          (epa-verify-region cleartext-start cleartext-end))))))
@@ -978,23 +1031,27 @@
   (save-excursion
     (let ((context (epg-make-context epa-protocol))
          signature)
-      ;;(epg-context-set-armor context epa-armor)
-      (epg-context-set-armor context t)
-      ;;(epg-context-set-textmode context epa-textmode)
-      (epg-context-set-textmode context t)
-      (epg-context-set-signers context signers)
-      (epg-context-set-passphrase-callback context
-                                          #'epa-passphrase-callback-function)
-      (epg-context-set-progress-callback context
-                                        (cons
-                                         #'epa-progress-callback-function
-                                         "Signing..."))
+      ;;(setf (epg-context-armor context) epa-armor)
+      (setf (epg-context-armor context) t)
+      ;;(setf (epg-context-textmode context) epa-textmode)
+      (setf (epg-context-textmode context) t)
+      (setf (epg-context-signers context) signers)
+      (setf (epg-context-passphrase-callback context)
+           #'epa-passphrase-callback-function)
+      (setf (epg-context-progress-callback context)
+           (cons
+            #'epa-progress-callback-function
+            "Signing..."))
       (message "Signing...")
-      (setq signature (epg-sign-string context
-                                      (epa--encode-coding-string
-                                       (buffer-substring start end)
-                                       epa-last-coding-system-specified)
-                                      mode))
+      (condition-case error
+         (setq signature (epg-sign-string context
+                                          (epa--encode-coding-string
+                                           (buffer-substring start end)
+                                           epa-last-coding-system-specified)
+                                          mode))
+       (error
+        (epa-display-error context)
+        (signal (car error) (cdr error))))
       (message "Signing...done")
       (delete-region start end)
       (goto-char start)
@@ -1061,25 +1118,29 @@
   (save-excursion
     (let ((context (epg-make-context epa-protocol))
          cipher)
-      ;;(epg-context-set-armor context epa-armor)
-      (epg-context-set-armor context t)
-      ;;(epg-context-set-textmode context epa-textmode)
-      (epg-context-set-textmode context t)
+      ;;(setf (epg-context-armor context) epa-armor)
+      (setf (epg-context-armor context) t)
+      ;;(setf (epg-context-textmode context) epa-textmode)
+      (setf (epg-context-textmode context) t)
       (if sign
-         (epg-context-set-signers context signers))
-      (epg-context-set-passphrase-callback context
-                                          #'epa-passphrase-callback-function)
-      (epg-context-set-progress-callback context
-                                        (cons
-                                         #'epa-progress-callback-function
-                                         "Encrypting..."))
+         (setf (epg-context-signers context) signers))
+      (setf (epg-context-passphrase-callback context)
+           #'epa-passphrase-callback-function)
+      (setf (epg-context-progress-callback context)
+           (cons
+            #'epa-progress-callback-function
+            "Encrypting..."))
       (message "Encrypting...")
-      (setq cipher (epg-encrypt-string context
-                                      (epa--encode-coding-string
-                                       (buffer-substring start end)
-                                       epa-last-coding-system-specified)
-                                      recipients
-                                      sign))
+      (condition-case error
+         (setq cipher (epg-encrypt-string context
+                                          (epa--encode-coding-string
+                                           (buffer-substring start end)
+                                           epa-last-coding-system-specified)
+                                          recipients
+                                          sign))
+       (error
+        (epa-display-error context)
+        (signal (car error) (cdr error))))
       (message "Encrypting...done")
       (delete-region start end)
       (goto-char start)
@@ -1105,7 +1166,11 @@
           (eq (nth 1 epa-list-keys-arguments) t))))
   (let ((context (epg-make-context epa-protocol)))
     (message "Deleting...")
-    (epg-delete-keys context keys allow-secret)
+    (condition-case error
+       (epg-delete-keys context keys allow-secret)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Deleting...done")
     (apply #'epa--list-keys epa-list-keys-arguments)))
 
@@ -1121,6 +1186,7 @@
          (epg-import-keys-from-file context file)
          (message "Importing %s...done" (file-name-nondirectory file)))
       (error
+       (epa-display-error context)
        (message "Importing %s...failed" (file-name-nondirectory file))))
     (if (epg-context-result-for context 'import)
        (epa-display-info (epg-import-result-to-string
@@ -1140,6 +1206,7 @@
          (epg-import-keys-from-string context (buffer-substring start end))
          (message "Importing...done"))
       (error
+       (epa-display-error context)
        (message "Importing...failed")))
     (if (epg-context-result-for context 'import)
        (epa-display-info (epg-import-result-to-string
@@ -1188,9 +1255,13 @@
             (file-name-directory default-name)
             default-name)))))
   (let ((context (epg-make-context epa-protocol)))
-    (epg-context-set-armor context epa-armor)
+    (setf (epg-context-armor context) epa-armor)
     (message "Exporting to %s..." (file-name-nondirectory file))
-    (epg-export-keys-to-file context keys file)
+    (condition-case error
+       (epg-export-keys-to-file context keys file)
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))
     (message "Exporting to %s...done" (file-name-nondirectory file))))
 
 ;;;###autoload
@@ -1198,12 +1269,16 @@
   "Insert selected KEYS after the point."
   (interactive
    (list (epa-select-keys (epg-make-context epa-protocol)
-                               "Select keys to export.
+                         "Select keys to export.
 If no one is selected, default public key is exported.  ")))
   (let ((context (epg-make-context epa-protocol)))
-    ;;(epg-context-set-armor context epa-armor)
-    (epg-context-set-armor context t)
-    (insert (epg-export-keys-to-string context keys))))
+    ;;(setf (epg-context-armor context) epa-armor)
+    (setf (epg-context-armor context) t)
+    (condition-case error
+       (insert (epg-export-keys-to-string context keys))
+      (error
+       (epa-display-error context)
+       (signal (car error) (cdr error))))))
 
 ;; (defun epa-sign-keys (keys &optional local)
 ;;   "Sign selected KEYS.
@@ -1217,12 +1292,12 @@
 ;;        (error "No keys selected"))
 ;;      (list keys current-prefix-arg)))
 ;;   (let ((context (epg-make-context epa-protocol)))
-;;     (epg-context-set-passphrase-callback context
-;;                                      #'epa-passphrase-callback-function)
-;;     (epg-context-set-progress-callback context
-;;                                    (cons
-;;                                     #'epa-progress-callback-function
-;;                                     "Signing keys..."))
+;;     (setf (epg-context-passphrase-callback context)
+;;          #'epa-passphrase-callback-function)
+;;     (setf (epg-context-progress-callback context)
+;;          (cons
+;;            #'epa-progress-callback-function
+;;            "Signing keys..."))
 ;;     (message "Signing keys...")
 ;;     (epg-sign-keys context keys local)
 ;;     (message "Signing keys...done")))