[PATCH] Fixes to sha1-el.el

[Simon Josefsson]

Here are some fixes made in Gnus CVS to sha1-el.el.  What do you
think?  I'm not sure if you also dislike OpenSSL, but perhaps
'sha1sum' is more portable, and thus might be installed in more
places.  Any suggestions appreciated.

2003-12-16  Simon Josefsson  <jas at extundo.com>

	* sha1-el.el (autoload): Don't use ignore-errors.
	(sha1-use-external): Use condition-case.  Suggested by Katsumi
	Yamaoka <yamaoka at jpl.org>.

2003-12-15  Simon Josefsson  <jas at extundo.com>

	* sha1-el.el (autoload): Ignore errors for
	executable-find. (XEmacs ecrypto does not require sh-script where
	executable.el is located.)
	(sha1-use-external): Likewise.

	* sha1-el.el (sha1): Add defgroup.
	(sha1-maximum-internal-length, sha1-program, sha1-use-external)
	(sha1-program): Use 'sha1sum' from GNU CoreUtils instead of OpenSSL.
	(sha1): Autoload.

2001-12-29  ShengHuo ZHU  <zsh at cs.rochester.edu>

	* sha1-el.el (sha1-use-external): New variable.
	(sha1-region): Use it.
	(sha1-string): Ditto.

Index: sha1-el.el
===================================================================
RCS file: /cvs/root/flim/Attic/sha1-el.el,v
retrieving revision 1.1.6.2
diff -u -p -u -w -r1.1.6.2 sha1-el.el
--- sha1-el.el	11 Mar 2001 10:10:53 -0000	1.1.6.2
+++ sha1-el.el	6 Jan 2004 14:14:43 -0000
@@ -1,6 +1,6 @@
 ;;; sha1-el.el --- SHA1 Secure Hash Algorithm in Emacs-Lisp.
 
-;; Copyright (C) 1999, 2001  Free Software Foundation, Inc.
+;; Copyright (C) 1999, 2001, 2003  Free Software Foundation, Inc.
 
 ;; Author: Shuhei KOBAYASHI <shuhei at aqua.ocn.ne.jp>
 ;; Keywords: SHA1, FIPS 180-1
@@ -54,20 +54,38 @@
 
 (require 'hex-util)
 
+(autoload 'executable-find "executable")
+
 ;;;
 ;;; external SHA1 function.
 ;;;
 
-(defvar sha1-maximum-internal-length 500
+(defgroup sha1 nil
+  "Elisp interface for SHA1 hash computation."
+  :group 'extensions)
+
+(defcustom sha1-maximum-internal-length 500
   "*Maximum length of message to use lisp version of SHA1 function.
 If message is longer than this, `sha1-program' is used instead.
 
 If this variable is set to 0, use extarnal program only.
-If this variable is set to nil, use internal function only.")
+If this variable is set to nil, use internal function only."
+  :type 'integer
+  :group 'sha1)
 
-(defvar sha1-program '("openssl" "sha1")
+(defcustom sha1-program '("sha1sum")
   "*Name of program to compute SHA1.
-It must be a string \(program name\) or list of strings \(name and its args\).")
+It must be a string \(program name\) or list of strings \(name and its args\)."
+  :type '(repeat string)
+  :group 'sha1)
+
+(defcustom sha1-use-external (condition-case ()
+				 (executable-find (car sha1-program))
+			       (error))
+  "*Use external SHA1 program.
+If this variable is set to nil, use internal function only."
+  :type 'boolean
+  :group 'sha1)
 
 (defun sha1-string-external (string)
   ;; `with-temp-buffer' is new in v20, so we do not use it.
@@ -396,17 +414,20 @@ It must be a string \(program name\) or 
 ;;;
 
 (defun sha1-region (beg end)
-  (if (and sha1-maximum-internal-length
+  (if (and sha1-use-external
+	   sha1-maximum-internal-length
 	   (> (abs (- end beg)) sha1-maximum-internal-length))
       (sha1-region-external beg end)
     (sha1-region-internal beg end)))
 
 (defun sha1-string (string)
-  (if (and sha1-maximum-internal-length
+  (if (and sha1-use-external
+	   sha1-maximum-internal-length
 	   (> (length string) sha1-maximum-internal-length))
       (sha1-string-external string)
     (sha1-string-internal string)))
 
+;;;###autoload
 (defun sha1 (object &optional beg end)
   "Return the SHA1 (Secure Hash Algorithm) of an object.
 OBJECT is either a string or a buffer.