;; Call mail-add-payment to add a hashcash payment to a mail message
;; in the current buffer.
;;
-;; To automatically add payments to all outgoing mail:
+;; Call mail-add-payment-async after writing the addresses but before
+;; writing the mail to start calculating the hashcash payment
+;; asynchronously.
+;;
+;; The easiest way to do this automatically for all outgoing mail
+;; is to set `message-generate-hashcash' to t. If you want more
+;; control, try the following hooks.
+;;
+;; To automatically add payments to all outgoing mail when sending:
;; (add-hook 'message-send-hook 'mail-add-payment)
+;;
+;; To start calculations automatically when addresses are prefilled:
+;; (add-hook 'message-setup-hook 'mail-add-payment-async)
+;;
+;; To check whether calculations are done before sending:
+;; (add-hook 'message-send-hook 'hashcash-wait-or-cancel)
;;; Code:
(eval-and-compile
(autoload 'executable-find "executable"))
-(defcustom hashcash-default-payment 10
+(defcustom hashcash-default-payment 20
"*The default number of bits to pay to unknown users.
If this is zero, no payment header will be generated.
See `hashcash-payment-alist'."
the value of hashcash payment to be made to that user. STRING, if
present, is the string to be hashed; if not present ADDR will be used.")
-(defcustom hashcash-default-accept-payment 10
+(defcustom hashcash-default-accept-payment 20
"*The default minimum number of bits to accept on incoming payments."
:type 'integer)
"*Specifies whether or not hashcash payments should be made to newsgroups."
:type 'boolean)
+(defvar hashcash-process-alist nil
+ "Alist of asynchronous hashcash processes and buffers.")
+
(require 'mail-utils)
(eval-and-compile
(hashcash-token-substring))
(error "No `hashcash' binary found")))
+(defun hashcash-generate-payment-async (str val callback)
+ "Generate a hashcash payment by finding a VAL-bit collison on STR.
+Return immediately. Call CALLBACK with process and result when ready."
+ (if (> val 0)
+ (let ((process (start-process "hashcash" nil
+ hashcash-path "-m" "-q" "-b" (number-to-string val) str)))
+ (setq hashcash-process-alist (cons
+ (cons process (current-buffer))
+ hashcash-process-alist))
+ (set-process-filter process `(lambda (process output)
+ (funcall ,callback process output))))
+ (funcall callback nil)))
+
(defun hashcash-check-payment (token str val)
"Check the validity of a hashcash payment."
(if hashcash-path
((equal (aref token 6) ?:) 1.1)
(t (error "Unknown hashcash format version"))))
+(defun hashcash-already-paid-p (recipient)
+ "Check for hashcash token to RECIPIENT in current buffer."
+ (save-excursion
+ (save-restriction
+ (message-narrow-to-headers-or-head)
+ (let ((token (message-fetch-field "x-hashcash")))
+ (and (stringp token)
+ (string-match (regexp-quote recipient) token))))))
+
;;;###autoload
(defun hashcash-insert-payment (arg)
"Insert X-Payment and X-Hashcash headers with a payment for ARG"
(interactive "sPay to: ")
- (let ((pay (hashcash-generate-payment (hashcash-payment-to arg)
- (hashcash-payment-required arg))))
- (when pay
+ (unless (hashcash-already-paid-p arg)
+ (let ((pay (hashcash-generate-payment (hashcash-payment-to arg)
+ (hashcash-payment-required arg))))
+ (when pay
+ ;; (insert-before-markers "X-Payment: hashcash "
+ ;; (number-to-string (hashcash-version pay)) " "
+ ;; pay "\n")
+ (insert-before-markers "X-Hashcash: " pay "\n")))))
+
+;;;###autoload
+(defun hashcash-insert-payment-async (arg)
+ "Insert X-Payment and X-Hashcash headers with a payment for ARG
+Only start calculation. Results are inserted when ready."
+ (interactive "sPay to: ")
+ (unless (hashcash-already-paid-p arg)
+ (hashcash-generate-payment-async (hashcash-payment-to arg)
+ (hashcash-payment-required arg)
+ `(lambda (process payment)
+ (hashcash-insert-payment-async-2 ,(current-buffer) process payment)))))
+
+(defun hashcash-insert-payment-async-2 (buffer process pay)
+ (with-current-buffer buffer
+ (save-excursion
+ (save-restriction
+ (setq hashcash-process-alist (delq
+ (assq process hashcash-process-alist)
+ hashcash-process-alist))
+ (goto-char (point-min))
+ (search-forward mail-header-separator)
+ (beginning-of-line)
+ (when pay
;; (insert-before-markers "X-Payment: hashcash "
;; (number-to-string (hashcash-version pay)) " "
;; pay "\n")
- (insert-before-markers "X-Hashcash: " pay "\n"))))
+ (insert-before-markers "X-Hashcash: " pay))))))
+
+(defun hashcash-cancel-async (&optional buffer)
+ "Delete any hashcash processes associated with BUFFER.
+BUFFER defaults to the current buffer."
+ (interactive)
+ (unless buffer (setq buffer (current-buffer)))
+ (let (entry)
+ (while (setq entry (rassq buffer hashcash-process-alist))
+ (delete-process (car entry))
+ (setq hashcash-process-alist
+ (delq entry hashcash-process-alist)))))
+
+(defun hashcash-wait-async (&optional buffer)
+ "Wait for asynchronous hashcash processes in BUFFER to finish.
+BUFFER defaults to the current buffer."
+ (interactive)
+ (unless buffer (setq buffer (current-buffer)))
+ (let (entry)
+ (while (setq entry (rassq buffer hashcash-process-alist))
+ (accept-process-output (car entry)))))
+
+(defun hashcash-processes-running-p (buffer)
+ "Return non-nil if hashcash processes in BUFFER are still running."
+ (rassq buffer hashcash-process-alist))
+
+(defun hashcash-wait-or-cancel ()
+ "Ask user whether to wait for hashcash processes to finish."
+ (interactive)
+ (when (hashcash-processes-running-p (current-buffer))
+ (if (y-or-n-p
+ "Hashcash process(es) still running; wait for them to finish? ")
+ (hashcash-wait-async)
+ (hashcash-cancel-async))))
;;;###autoload
(defun hashcash-verify-payment (token &optional resource amount)
(t nil))))
;;;###autoload
-(defun mail-add-payment (&optional arg)
+(defun mail-add-payment (&optional arg async)
"Add X-Payment: and X-Hashcash: headers with a hashcash payment
-for each recipient address. Prefix arg sets default payment temporarily."
+for each recipient address. Prefix arg sets default payment temporarily.
+Set ASYNC to t to start asynchronous calculation. (See
+`mail-add-payment-async')."
(interactive "P")
(let ((hashcash-default-payment (if arg (prefix-numeric-value arg)
hashcash-default-payment))
(when (and hashcash-in-news ng)
(setq addrlist (nconc addrlist (split-string ng ",[ \t\n]*")))))
(when addrlist
- (mapcar #'hashcash-insert-payment addrlist))))) ; mapc
+ (mapcar (if async
+ #'hashcash-insert-payment-async
+ #'hashcash-insert-payment)
+ addrlist))))) ; mapc
t)
+;;;###autoload
+(defun mail-add-payment-async (&optional arg)
+ "Add X-Payment: and X-Hashcash: headers with a hashcash payment
+for each recipient address. Prefix arg sets default payment temporarily.
+Calculation is asynchronous."
+ (interactive "P")
+ (mail-add-payment arg t))
+
;;;###autoload
(defun mail-check-payment (&optional arg)
"Look for a valid X-Payment: or X-Hashcash: header.
projects / gnus / commitdiff