Drop some epg/epa backwards compat code for ancient Emacs versions

* lisp/epa.el (epa--select-safe-coding-system): Remove,
`select-safe-coding-system' has been present since Emacs 20.3.
(epa--encode-coding-string, epa--decode-coding-string):
* lisp/epg.el (epg--decode-coding-string, epg--encode-coding-string)
(epg--clear-string): Remove, the corresponding Emacs functions are so
old they don't show up in NEWS.  Furthermore, the fallback for
the *-coding-string functions was `identity' which wouldn't have
worked anyway, since it only takes a single argument.
(epg--make-temp-file): Remove, `make-temp-file' has been present since
Emacs 21.1.
* lisp/epg-config.el (epg-gpg-program, epg-gpgsm-program)
(epg-gpgconf-program, epg-gpg-home-directory)
(epg-passphrase-coding-system, epg-debug): Remove unneeded :group
parameter.

4 files changed, 33 insertions, 123 deletions

diff --git a/lisp/epa-mail.el b/lisp/epa-mail.el
index c819f6734c7..7f4c28e9670 100644
--- a/lisp/epa-mail.el
+++ b/lisp/epa-mail.el
@@ -95,7 +95,7 @@ The buffer is expected to contain a mail message."
          (forward-line))
      (setq epa-last-coding-system-specified
            (or coding-system-for-write
-               (epa--select-safe-coding-system (point) (point-max))))
+               (select-safe-coding-system (point) (point-max))))
      (let ((verbose current-prefix-arg))
        (list (point) (point-max)
              (if verbose
@@ -222,7 +222,7 @@ If no one is selected, symmetric encryption will be performed.  "
 
       (setq epa-last-coding-system-specified
             (or coding-system-for-write
-                (epa--select-safe-coding-system (point) (point-max)))))
+                (select-safe-coding-system (point) (point-max)))))
 
     ;; Don't let some read-only text stop us from encrypting.
     (let ((inhibit-read-only t))
diff --git a/lisp/epa.el b/lisp/epa.el
index 70f27e272fc..a375cd61707 100644
--- a/lisp/epa.el
+++ b/lisp/epa.el
@@ -307,12 +307,6 @@ You should bind this variable with `let', but do not set it globally.")
           (epg-sub-key-id (car (epg-key-sub-key-list
                                 (widget-get widget :value))))))
 
-(defalias 'epa--encode-coding-string
-  (if (fboundp 'encode-coding-string) #'encode-coding-string #'identity))
-
-(defalias 'epa--decode-coding-string
-  (if (fboundp 'decode-coding-string) #'decode-coding-string #'identity))
-
 (define-derived-mode epa-key-list-mode special-mode "Keys"
   "Major mode for `epa-list-keys'."
   (buffer-disable-undo)
@@ -879,7 +873,7 @@ For example:
          (epa-display-error context)
          (signal (car error) (cdr error))))
       (message "Decrypting...done")
-      (setq plain (epa--decode-coding-string
+      (setq plain (decode-coding-string
                    plain
                    (or coding-system-for-read
                        (get-text-property start 'epa-coding-system-used)
@@ -973,7 +967,7 @@ For example:
     (condition-case error
         (setq plain (epg-verify-string
                      context
-                     (epa--encode-coding-string
+                     (encode-coding-string
                       (buffer-substring start end)
                       (or coding-system-for-write
                           (get-text-property start 'epa-coding-system-used)))))
@@ -981,7 +975,7 @@ For example:
        (epa-display-error context)
        (signal (car error) (cdr error))))
     (message "Verifying...done")
-    (setq plain (epa--decode-coding-string
+    (setq plain (decode-coding-string
                  plain
                  (or coding-system-for-read
                      (get-text-property start 'epa-coding-system-used)
@@ -1029,12 +1023,6 @@ See the reason described in the `epa-verify-region' documentation."
             (error "No cleartext tail"))
           (epa-verify-region cleartext-start cleartext-end))))))
 
-(defalias 'epa--select-safe-coding-system
-  (if (fboundp 'select-safe-coding-system)
-      #'select-safe-coding-system
-    (lambda (_from _to)
-      buffer-file-coding-system)))
-
 ;;;###autoload
 (defun epa-sign-region (start end signers mode)
   "Sign the current region between START and END by SIGNERS keys selected.
@@ -1057,7 +1045,7 @@ For example:
    (let ((verbose current-prefix-arg))
      (setq epa-last-coding-system-specified
            (or coding-system-for-write
-               (epa--select-safe-coding-system
+               (select-safe-coding-system
                 (region-beginning) (region-end))))
      (list (region-beginning) (region-end)
            (if verbose
@@ -1086,7 +1074,7 @@ If no one is selected, default secret key is used.  "
       (message "Signing...")
       (condition-case error
           (setq signature (epg-sign-string context
-                                           (epa--encode-coding-string
+                                           (encode-coding-string
                                             (buffer-substring start end)
                                             epa-last-coding-system-specified)
                                            mode))
@@ -1098,7 +1086,7 @@ If no one is selected, default secret key is used.  "
       (goto-char start)
       (add-text-properties (point)
                            (progn
-                             (insert (epa--decode-coding-string
+                             (insert (decode-coding-string
                                       signature
                                       (or coding-system-for-read
                                           epa-last-coding-system-specified)))
@@ -1146,7 +1134,7 @@ For example:
          sign)
      (setq epa-last-coding-system-specified
            (or coding-system-for-write
-               (epa--select-safe-coding-system
+               (select-safe-coding-system
                 (region-beginning) (region-end))))
      (list (region-beginning) (region-end)
            (epa-select-keys context
@@ -1175,7 +1163,7 @@ If no one is selected, symmetric encryption will be performed.  ")
       (message "Encrypting...")
       (condition-case error
           (setq cipher (epg-encrypt-string context
-                                           (epa--encode-coding-string
+                                           (encode-coding-string
                                             (buffer-substring start end)
                                             epa-last-coding-system-specified)
                                            recipients
diff --git a/lisp/epg-config.el b/lisp/epg-config.el
index d30ebea2d66..bf9360cdb4f 100644
--- a/lisp/epg-config.el
+++ b/lisp/epg-config.el
@@ -48,36 +48,30 @@
 Setting this variable directly does not take effect;
 instead use \\[customize] (see the info node `Easy Customization')."
   :version "25.1"
-  :group 'epg
   :type 'string)
 
 (defcustom epg-gpgsm-program "gpgsm"
   "The `gpgsm' executable.
 Setting this variable directly does not take effect;
 instead use \\[customize] (see the info node `Easy Customization')."
-  :group 'epg
   :type 'string)
 
 (defcustom epg-gpgconf-program "gpgconf"
   "The `gpgconf' executable."
   :version "25.1"
-  :group 'epg
   :type 'string)
 
 (defcustom epg-gpg-home-directory nil
   "The directory which contains the configuration files of `epg-gpg-program'."
-  :group 'epg
   :type '(choice (const :tag "Default" nil) directory))
 
 (defcustom epg-passphrase-coding-system nil
   "Coding system to use with messages from `epg-gpg-program'."
-  :group 'epg
   :type 'symbol)
 
 (defcustom epg-debug nil
   "If non-nil, debug output goes to the \" *epg-debug*\" buffer.
 Note that the buffer name starts with a space."
-  :group 'epg
   :type 'boolean)
 
 (defconst epg-gpg-minimum-version "1.4.3")
diff --git a/lisp/epg.el b/lisp/epg.el
index 091021936ad..e6b4af2b36e 100644
--- a/lisp/epg.el
+++ b/lisp/epg.el
@@ -760,18 +760,13 @@ callback data (if any)."
            (file-exists-p (epg-context-output-file context)))
       (delete-file (epg-context-output-file context))))
 
-(eval-and-compile
-  (if (fboundp 'decode-coding-string)
-      (defalias 'epg--decode-coding-string 'decode-coding-string)
-    (defalias 'epg--decode-coding-string 'identity)))
-
 (defun epg--status-USERID_HINT (_context string)
   (if (string-match "\\`\\([^ ]+\\) \\(.*\\)" string)
       (let* ((key-id (match-string 1 string))
              (user-id (match-string 2 string))
              (entry (assoc key-id epg-user-id-alist)))
         (condition-case nil
-            (setq user-id (epg--decode-coding-string
+            (setq user-id (decode-coding-string
                            (epg--decode-percent-escape user-id)
                            'utf-8))
           (error))
@@ -790,17 +785,6 @@ callback data (if any)."
 (defun epg--status-NEED_PASSPHRASE_PIN (_context _string)
   (setq epg-key-id 'PIN))
 
-(eval-and-compile
-  (if (fboundp 'clear-string)
-      (defalias 'epg--clear-string 'clear-string)
-    (defun epg--clear-string (string)
-      (fillarray string 0))))
-
-(eval-and-compile
-  (if (fboundp 'encode-coding-string)
-      (defalias 'epg--encode-coding-string 'encode-coding-string)
-    (defalias 'epg--encode-coding-string 'identity)))
-
 (defun epg--status-GET_HIDDEN (context string)
   (when (and epg-key-id
              (string-match "\\`passphrase\\." string))
@@ -821,16 +805,16 @@ callback data (if any)."
                        (cdr (epg-context-passphrase-callback context))))
                 (when passphrase
                   (setq passphrase-with-new-line (concat passphrase "\n"))
-                  (epg--clear-string passphrase)
+                  (clear-string passphrase)
                   (setq passphrase nil)
                   (if epg-passphrase-coding-system
                       (progn
                         (setq encoded-passphrase-with-new-line
-                              (epg--encode-coding-string
+                              (encode-coding-string
                                passphrase-with-new-line
                                (coding-system-change-eol-conversion
                                 epg-passphrase-coding-system 'unix)))
-                        (epg--clear-string passphrase-with-new-line)
+                        (clear-string passphrase-with-new-line)
                         (setq passphrase-with-new-line nil))
                     (setq encoded-passphrase-with-new-line
                           passphrase-with-new-line
@@ -844,11 +828,11 @@ callback data (if any)."
                     (epg-context-result-for context 'error)))
              (delete-process (epg-context-process context))))
         (if passphrase
-            (epg--clear-string passphrase))
+            (clear-string passphrase))
         (if passphrase-with-new-line
-            (epg--clear-string passphrase-with-new-line))
+            (clear-string passphrase-with-new-line))
         (if encoded-passphrase-with-new-line
-            (epg--clear-string encoded-passphrase-with-new-line))))))
+            (clear-string encoded-passphrase-with-new-line))))))
 
 (defun epg--prompt-GET_BOOL (_context string)
   (let ((entry (assoc string epg-prompt-alist)))
@@ -911,7 +895,7 @@ callback data (if any)."
         (condition-case nil
             (if (eq (epg-context-protocol context) 'CMS)
                 (setq user-id (epg-dn-from-string user-id))
-              (setq user-id (epg--decode-coding-string
+              (setq user-id (decode-coding-string
                              (epg--decode-percent-escape user-id)
                              'utf-8)))
           (error))
@@ -1192,7 +1176,7 @@ callback data (if any)."
              (user-id (match-string 2 string))
              (entry (assoc key-id epg-user-id-alist)))
         (condition-case nil
-            (setq user-id (epg--decode-coding-string
+            (setq user-id (decode-coding-string
                            (epg--decode-percent-escape user-id)
                            'utf-8))
           (error))
@@ -1349,7 +1333,7 @@ NAME is either a string or a list of strings."
           (setq string (replace-match "\\\"" t t string)
                 index (1+ (match-end 0))))
         (condition-case nil
-            (setq string (epg--decode-coding-string
+            (setq string (decode-coding-string
                           (car (read-from-string (concat "\"" string "\"")))
                           'utf-8))
           (error
@@ -1394,62 +1378,6 @@ NAME is either a string or a list of strings."
       (setq pointer (cdr pointer)))
     keys))
 
-(eval-and-compile
-  (if (fboundp 'make-temp-file)
-      (defalias 'epg--make-temp-file 'make-temp-file)
-    (defvar temporary-file-directory)
-    ;; stolen from poe.el.
-    (defun epg--make-temp-file (prefix)
-      "Create a temporary file.
-The returned file name (created by appending some random characters at the end
-of PREFIX, and expanding against `temporary-file-directory' if necessary),
-is guaranteed to point to a newly created empty file.
-You can then use `write-region' to write new data into the file."
-      (let ((orig-modes (default-file-modes))
-            tempdir tempfile)
-        (setq prefix (expand-file-name prefix
-                                       (if (featurep 'xemacs)
-                                           (temp-directory)
-                                         temporary-file-directory)))
-        (unwind-protect
-            (let (file)
-              ;; First, create a temporary directory.
-              (set-default-file-modes #o700)
-              (while (condition-case ()
-                         (progn
-                           (setq tempdir (make-temp-name
-                                          (concat
-                                           (file-name-directory prefix)
-                                           "DIR")))
-                           ;; return nil or signal an error.
-                           (make-directory tempdir))
-                       ;; let's try again.
-                       (file-already-exists t)))
-              ;; Second, create a temporary file in the tempdir.
-              ;; There *is* a race condition between `make-temp-name'
-              ;; and `write-region', but we don't care it since we are
-              ;; in a private directory now.
-              (setq tempfile (make-temp-name (concat tempdir "/EMU")))
-              (write-region "" nil tempfile nil 'silent)
-              ;; Finally, make a hard-link from the tempfile.
-              (while (condition-case ()
-                         (progn
-                           (setq file (make-temp-name prefix))
-                           ;; return nil or signal an error.
-                           (add-name-to-file tempfile file))
-                       ;; let's try again.
-                       (file-already-exists t)))
-              file)
-          (set-default-file-modes orig-modes)
-          ;; Cleanup the tempfile.
-          (and tempfile
-               (file-exists-p tempfile)
-               (delete-file tempfile))
-          ;; Cleanup the tempdir.
-          (and tempdir
-               (file-directory-p tempdir)
-               (delete-directory tempdir)))))))
-
 (defun epg--args-from-sig-notations (notations)
   (apply #'nconc
          (mapcar
@@ -1513,7 +1441,7 @@ If PLAIN is nil, it returns the result as a string."
   (unwind-protect
       (progn
         (setf (epg-context-output-file context)
-              (or plain (epg--make-temp-file "epg-output")))
+              (or plain (make-temp-file "epg-output")))
         (epg-start-decrypt context (epg-make-data-from-file cipher))
         (epg-wait-for-completion context)
         (epg--check-error-for-decrypt context)
@@ -1525,13 +1453,13 @@ If PLAIN is nil, it returns the result as a string."
 
 (defun epg-decrypt-string (context cipher)
   "Decrypt a string CIPHER and return the plain text."
-  (let ((input-file (epg--make-temp-file "epg-input"))
+  (let ((input-file (make-temp-file "epg-input"))
         (coding-system-for-write 'binary))
     (unwind-protect
         (progn
           (write-region cipher nil input-file nil 'quiet)
           (setf (epg-context-output-file context)
-                (epg--make-temp-file "epg-output"))
+                (make-temp-file "epg-output"))
           (epg-start-decrypt context (epg-make-data-from-file input-file))
           (epg-wait-for-completion context)
           (epg--check-error-for-decrypt context)
@@ -1602,7 +1530,7 @@ which will return a list of `epg-signature' object."
   (unwind-protect
       (progn
         (setf (epg-context-output-file context)
-              (or plain (epg--make-temp-file "epg-output")))
+              (or plain (make-temp-file "epg-output")))
         (if signed-text
             (epg-start-verify context
                               (epg-make-data-from-file signature)
@@ -1639,10 +1567,10 @@ which will return a list of `epg-signature' object."
     (unwind-protect
         (progn
           (setf (epg-context-output-file context)
-                (epg--make-temp-file "epg-output"))
+                (make-temp-file "epg-output"))
           (if signed-text
               (progn
-                (setq input-file (epg--make-temp-file "epg-signature"))
+                (setq input-file (make-temp-file "epg-signature"))
                 (write-region signature nil input-file nil 'quiet)
                 (epg-start-verify context
                                   (epg-make-data-from-file input-file)
@@ -1710,7 +1638,7 @@ Otherwise, it makes a cleartext signature."
   (unwind-protect
       (progn
         (setf (epg-context-output-file context)
-              (or signature (epg--make-temp-file "epg-output")))
+              (or signature (make-temp-file "epg-output")))
         (epg-start-sign context (epg-make-data-from-file plain) mode)
         (epg-wait-for-completion context)
         (unless (epg-context-result-for context 'sign)
@@ -1730,12 +1658,12 @@ If it is nil or `normal', it makes a normal signature.
 Otherwise, it makes a cleartext signature."
   (let ((input-file
          (unless (eq (epg-context-protocol context) 'CMS)
-           (epg--make-temp-file "epg-input")))
+           (make-temp-file "epg-input")))
         (coding-system-for-write 'binary))
     (unwind-protect
         (progn
           (setf (epg-context-output-file context)
-                (epg--make-temp-file "epg-output"))
+                (make-temp-file "epg-output"))
           (if input-file
               (write-region plain nil input-file nil 'quiet))
           (epg-start-sign context
@@ -1812,7 +1740,7 @@ If RECIPIENTS is nil, it performs symmetric encryption."
   (unwind-protect
       (progn
         (setf (epg-context-output-file context)
-              (or cipher (epg--make-temp-file "epg-output")))
+              (or cipher (make-temp-file "epg-output")))
         (epg-start-encrypt context (epg-make-data-from-file plain)
                            recipients sign always-trust)
         (epg-wait-for-completion context)
@@ -1837,12 +1765,12 @@ If RECIPIENTS is nil, it performs symmetric encryption."
   (let ((input-file
          (unless (or (not sign)
                      (eq (epg-context-protocol context) 'CMS))
-           (epg--make-temp-file "epg-input")))
+           (make-temp-file "epg-input")))
         (coding-system-for-write 'binary))
     (unwind-protect
         (progn
           (setf (epg-context-output-file context)
-                (epg--make-temp-file "epg-output"))
+                (make-temp-file "epg-output"))
           (if input-file
               (write-region plain nil input-file nil 'quiet))
           (epg-start-encrypt context
@@ -1887,7 +1815,7 @@ If you are unsure, use synchronous version of this function
   (unwind-protect
       (progn
         (setf (epg-context-output-file context)
-              (or file (epg--make-temp-file "epg-output")))
+              (or file (make-temp-file "epg-output")))
         (epg-start-export-keys context keys)
         (epg-wait-for-completion context)
         (let ((errors (epg-context-result-for context 'error)))