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)))