;;; epg-config.el --- configuration of the EasyPG Library
-;; Copyright (C) 2006-2013 Free Software Foundation, Inc.
+;; Copyright (C) 2006-2016 Free Software Foundation, Inc.
;; Author: Daiki Ueno <ueno@unixuser.org>
;; Keywords: PGP, GnuPG
;;; Code:
+(eval-when-compile (require 'cl-lib))
+
(defconst epg-package-name "epg"
"Name of this package.")
:group 'data
:group 'external)
-(defcustom epg-gpg-program (or (executable-find "gpg")
- (executable-find "gpg2")
- "gpg")
+(defcustom epg-gpg-program (if (executable-find "gpg2")
+ "gpg2"
+ "gpg")
"The `gpg' executable."
+ :version "25.1"
:group 'epg
:type 'string)
: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
(defconst epg-gpg-minimum-version "1.4.3")
+(defconst epg-config--program-alist
+ '((OpenPGP
+ epg-gpg-program
+ ("gpg2" . "2.1.6") ("gpg" . "1.4.3"))
+ (CMS
+ epg-gpgsm-program
+ ("gpgsm" . "2.0.4")))
+ "Alist used to obtain the usable configuration of executables.
+The first element of each entry is protocol symbol, which is
+either `OpenPGP' or `CMS'. The second element is a symbol where
+the executable name is remembered. The rest of the entry is an
+alist mapping executable names to the minimum required version
+suitable for the use with Emacs.")
+
+(defconst epg-config--configuration-constructor-alist
+ '((OpenPGP . epg-config--make-gpg-configuration)
+ (CMS . epg-config--make-gpgsm-configuration))
+ "Alist used to obtain the usable configuration of executables.
+The first element of each entry is protocol symbol, which is
+either `OpenPGP' or `CMS'. The second element is a function
+which constructs a configuration object (actually a plist).")
+
+(defvar epg--configurations nil)
+
;;;###autoload
-(defun epg-configuration ()
- "Return a list of internal configuration parameters of `epg-gpg-program'."
+(defun epg-find-configuration (protocol &optional no-cache program-alist)
+ "Find or create a usable configuration to handle PROTOCOL.
+This function first looks at the existing configuration found by
+the previous invocation of this function, unless NO-CACHE is non-nil.
+
+Then it walks through PROGRAM-ALIST or
+`epg-config--program-alist'. If `epg-gpg-program' or
+`epg-gpgsm-program' is already set with custom, use it.
+Otherwise, it tries the programs listed in the entry until the
+version requirement is met."
+ (unless program-alist
+ (setq program-alist epg-config--program-alist))
+ (let ((entry (assq protocol program-alist)))
+ (unless entry
+ (error "Unknown protocol %S" protocol))
+ (cl-destructuring-bind (symbol . alist)
+ (cdr entry)
+ (let ((constructor
+ (alist-get protocol epg-config--configuration-constructor-alist)))
+ (or (and (not no-cache) (alist-get protocol epg--configurations))
+ ;; If the executable value is already set with M-x
+ ;; customize, use it without checking.
+ (if (and symbol (get symbol 'saved-value))
+ (let ((configuration
+ (funcall constructor (symbol-value symbol))))
+ (push (cons protocol configuration) epg--configurations)
+ configuration)
+ (catch 'found
+ (dolist (program-version alist)
+ (let ((executable (executable-find (car program-version))))
+ (when executable
+ (let ((configuration
+ (funcall constructor executable)))
+ (when (ignore-errors
+ (epg-check-configuration configuration
+ (cdr program-version))
+ t)
+ (unless no-cache
+ (push (cons protocol configuration)
+ epg--configurations))
+ (throw 'found configuration)))))))))))))
+
+;; Create an `epg-configuration' object for `gpg', using PROGRAM.
+(defun epg-config--make-gpg-configuration (program)
(let (config groups type args)
(with-temp-buffer
- (apply #'call-process epg-gpg-program nil (list t nil) nil
+ (apply #'call-process program nil (list t nil) nil
(append (if epg-gpg-home-directory
(list "--homedir" epg-gpg-home-directory))
'("--with-colons" "--list-config")))
type args))))
(t
(setq config (cons (cons type args) config))))))
+ (push (cons 'program program) config)
(if groups
(cons (cons 'groups groups) config)
config)))
+;; Create an `epg-configuration' object for `gpgsm', using PROGRAM.
+(defun epg-config--make-gpgsm-configuration (program)
+ (with-temp-buffer
+ (call-process program nil (list t nil) nil "--version")
+ (goto-char (point-min))
+ (when (looking-at "\\S-+ (")
+ (goto-char (match-end 0))
+ (backward-char)
+ (forward-sexp)
+ (skip-syntax-forward "-" (point-at-eol))
+ (list (cons 'program program)
+ (cons 'version (buffer-substring (point) (point-at-eol)))))))
+
+;;;###autoload
+(defun epg-configuration ()
+ "Return a list of internal configuration parameters of `epg-gpg-program'."
+ (declare (obsolete epg-find-configuration "25.1"))
+ (epg-config--make-gpg-configuration epg-gpg-program))
+
(defun epg-config--parse-version (string)
(let ((index 0)
version)