2006-03-21 Simon Josefsson <jas@extundo.com>

	* pgg-gpg.el: Ideas below based on patch from Sascha Wilde
	<wilde@sha-bang.de>.
	(pgg-gpg-use-agent): New variable.
	(pgg-gpg-process-region): Use it.
	(pgg-gpg-encrypt-region): Likewise.
	(pgg-gpg-encrypt-symmetric-region): Likewise.
	(pgg-gpg-decrypt-region): Likewise.
	(pgg-gpg-sign-region): Likewise.
	(pgg-gpg-possibly-cache-passphrase): Don't cache a nil password.

2 files changed, 43 insertions, 18 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 4c325e968ca..22a05486c9e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,15 @@
+2006-03-21  Simon Josefsson  <jas@extundo.com>
+
+	* pgg-gpg.el: Ideas below based on patch from Sascha Wilde
+	<wilde@sha-bang.de>.
+	(pgg-gpg-use-agent): New variable.
+	(pgg-gpg-process-region): Use it.
+	(pgg-gpg-encrypt-region): Likewise.
+	(pgg-gpg-encrypt-symmetric-region): Likewise.
+	(pgg-gpg-decrypt-region): Likewise.
+	(pgg-gpg-sign-region): Likewise.
+	(pgg-gpg-possibly-cache-passphrase): Don't cache a nil password.
+
 2006-03-21  Carsten Dominik  <dominik@science.uva.nl>
 
 	* textmodes/org.el: (org-open-at-point): Fixed bug in wiki-style
diff --git a/lisp/pgg-gpg.el b/lisp/pgg-gpg.el
index 0c9f45ab5b9..28512dce8fc 100644
--- a/lisp/pgg-gpg.el
+++ b/lisp/pgg-gpg.el
@@ -51,6 +51,13 @@
   :type '(choice (const :tag "New `--recipient' option" "--recipient")
 		 (const :tag "Old `--remote-user' option" "--remote-user")))
 
+(defcustom pgg-gpg-use-agent (if (getenv "GPG_AGENT_INFO") t nil)
+  "Whether to use gnupg agent for key caching.
+By default, it will be enabled iff the environment variable
+\"GPG_AGENT_INFO\" is set."
+  :group 'pgg-gpg
+  :type 'boolean)
+
 (defvar pgg-gpg-user-id nil
   "GnuPG ID of your default identity.")
 
@@ -58,7 +65,8 @@
   (let* ((output-file-name (pgg-make-temp-file "pgg-output"))
 	 (args
 	  `("--status-fd" "2"
-	    ,@(if passphrase '("--passphrase-fd" "0"))
+	    ,@(if pgg-gpg-use-agent '("--use-agent")
+		(if passphrase '("--passphrase-fd" "0")))
 	    "--yes" ; overwrite
 	    "--output" ,output-file-name
 	    ,@pgg-gpg-extra-args ,@args))
@@ -100,7 +108,8 @@
       (set-default-file-modes orig-mode))))
 
 (defun pgg-gpg-possibly-cache-passphrase (passphrase &optional key notruncate)
-  (if (and pgg-cache-passphrase
+  (if (and passphrase
+	   pgg-cache-passphrase
 	   (progn
 	     (goto-char (point-min))
 	     (re-search-forward "^\\[GNUPG:] \\(GOOD_PASSPHRASE\\>\\)\\|\\(SIG_CREATED\\)" nil t)))
@@ -182,11 +191,11 @@ If optional PASSPHRASE is not specified, it will be obtained from the
 passphrase cache or user."
   (let* ((pgg-gpg-user-id (or pgg-gpg-user-id pgg-default-user-id))
 	 (passphrase (or passphrase
-                         (when sign
-                           (pgg-read-passphrase
-                            (format "GnuPG passphrase for %s: "
-                                    pgg-gpg-user-id)
-                            pgg-gpg-user-id))))
+			 (when (and sign (not pgg-gpg-use-agent))
+			   (pgg-read-passphrase
+			    (format "GnuPG passphrase for %s: "
+				    pgg-gpg-user-id)
+			    pgg-gpg-user-id))))
 	 (args
 	  (append
 	   (list "--batch" "--armor" "--always-trust" "--encrypt")
@@ -214,8 +223,9 @@ passphrase cache or user."
 If optional PASSPHRASE is not specified, it will be obtained from the
 passphrase cache or user."
   (let* ((passphrase (or passphrase
-                         (pgg-read-passphrase
-                          "GnuPG passphrase for symmetric encryption: ")))
+			 (when (not pgg-gpg-use-agent)
+			   (pgg-read-passphrase
+			    "GnuPG passphrase for symmetric encryption: "))))
 	 (args
 	  (append (list "--batch" "--armor" "--symmetric" )
 		  (if pgg-text-mode (list "--textmode")))))
@@ -242,12 +252,13 @@ passphrase cache or user."
 	 (pgg-gpg-user-id (or key-id key
 	                      pgg-gpg-user-id pgg-default-user-id))
 	 (passphrase (or passphrase
-                         (pgg-read-passphrase
-                          (format (if (pgg-gpg-symmetric-key-p message-keys)
-                                      "Passphrase for symmetric decryption: "
-                                    "GnuPG passphrase for %s: ")
-                                  (or key-owner "??"))
-                          pgg-gpg-user-id)))
+			 (when (not pgg-gpg-use-agent)
+			   (pgg-read-passphrase
+			    (format (if (pgg-gpg-symmetric-key-p message-keys)
+					"Passphrase for symmetric decryption: "
+				      "GnuPG passphrase for %s: ")
+				    (or key-owner "??"))
+			    pgg-gpg-user-id))))
 	 (args '("--batch" "--decrypt")))
     (pgg-gpg-process-region start end passphrase pgg-gpg-program args)
     (with-current-buffer pgg-errors-buffer
@@ -277,9 +288,11 @@ passphrase cache or user."
   "Make detached signature from text between START and END."
   (let* ((pgg-gpg-user-id (or pgg-gpg-user-id pgg-default-user-id))
 	 (passphrase (or passphrase
-                         (pgg-read-passphrase
-                          (format "GnuPG passphrase for %s: " pgg-gpg-user-id)
-                          pgg-gpg-user-id)))
+			 (when (not pgg-gpg-use-agent)
+			   (pgg-read-passphrase
+			    (format "GnuPG passphrase for %s: "
+				    pgg-gpg-user-id)
+			    pgg-gpg-user-id))))
 	 (args
 	  (append (list (if cleartext "--clearsign" "--detach-sign")
 			"--armor" "--batch" "--verbose"