mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-12-05 08:53:45 +00:00
125 lines
4.2 KiB
EmacsLisp
125 lines
4.2 KiB
EmacsLisp
;;; tq.el --- utility to maintain a transaction queue
|
|
|
|
;; Copyright (C) 1985, 1986, 1987, 1992, 2003 Free Software Foundation, Inc.
|
|
|
|
;; Author: Scott Draves <spot@cs.cmu.edu>
|
|
;; Maintainer: FSF
|
|
;; Adapted-By: ESR
|
|
;; Keywords: extensions
|
|
|
|
;; This file is part of GNU Emacs.
|
|
|
|
;; GNU Emacs is free software; you can redistribute it and/or modify
|
|
;; it under the terms of the GNU General Public License as published by
|
|
;; the Free Software Foundation; either version 2, or (at your option)
|
|
;; any later version.
|
|
|
|
;; GNU Emacs is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
;; GNU General Public License for more details.
|
|
|
|
;; You should have received a copy of the GNU General Public License
|
|
;; along with GNU Emacs; see the file COPYING. If not, write to the
|
|
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
;; Boston, MA 02111-1307, USA.
|
|
|
|
;;; Commentary:
|
|
|
|
;; manages receiving a stream asynchronously,
|
|
;; parsing it into transactions, and then calling
|
|
;; handler functions
|
|
|
|
;; Our basic structure is the queue/process/buffer triple. Each entry
|
|
;; of the queue is a regexp/closure/function triple. We buffer
|
|
;; bytes from the process until we see the regexp at the head of the
|
|
;; queue. Then we call the function with the closure and the
|
|
;; collected bytes.
|
|
|
|
;;; Code:
|
|
|
|
;;;###autoload
|
|
(defun tq-create (process)
|
|
"Create and return a transaction queue communicating with PROCESS.
|
|
PROCESS should be a subprocess capable of sending and receiving
|
|
streams of bytes. It may be a local process, or it may be connected
|
|
to a tcp server on another machine."
|
|
(let ((tq (cons nil (cons process
|
|
(generate-new-buffer
|
|
(concat " tq-temp-"
|
|
(process-name process)))))))
|
|
(set-process-filter process
|
|
`(lambda (proc string)
|
|
(tq-filter ',tq string)))
|
|
tq))
|
|
|
|
;;; accessors
|
|
(defun tq-queue (tq) (car tq))
|
|
(defun tq-process (tq) (car (cdr tq)))
|
|
(defun tq-buffer (tq) (cdr (cdr tq)))
|
|
|
|
(defun tq-queue-add (tq re closure fn)
|
|
(setcar tq (nconc (tq-queue tq)
|
|
(cons (cons re (cons closure fn)) nil)))
|
|
'ok)
|
|
|
|
(defun tq-queue-head-regexp (tq) (car (car (tq-queue tq))))
|
|
(defun tq-queue-head-fn (tq) (cdr (cdr (car (tq-queue tq)))))
|
|
(defun tq-queue-head-closure (tq) (car (cdr (car (tq-queue tq)))))
|
|
(defun tq-queue-empty (tq) (not (tq-queue tq)))
|
|
(defun tq-queue-pop (tq) (setcar tq (cdr (car tq))) (null (car tq)))
|
|
|
|
|
|
;;; must add to queue before sending!
|
|
(defun tq-enqueue (tq question regexp closure fn)
|
|
"Add a transaction to transaction queue TQ.
|
|
This sends the string QUESTION to the process that TQ communicates with.
|
|
When the corresponding answer comes back, we call FN
|
|
with two arguments: CLOSURE, and the answer to the question.
|
|
REGEXP is a regular expression to match the entire answer;
|
|
that's how we tell where the answer ends."
|
|
(tq-queue-add tq regexp closure fn)
|
|
(process-send-string (tq-process tq) question))
|
|
|
|
(defun tq-close (tq)
|
|
"Shut down transaction queue TQ, terminating the process."
|
|
(delete-process (tq-process tq))
|
|
(kill-buffer (tq-buffer tq)))
|
|
|
|
(defun tq-filter (tq string)
|
|
"Append STRING to the TQ's buffer; then process the new data."
|
|
(with-current-buffer (tq-buffer tq)
|
|
(goto-char (point-max))
|
|
(insert string)
|
|
(tq-process-buffer tq)))
|
|
|
|
(defun tq-process-buffer (tq)
|
|
"Check TQ's buffer for the regexp at the head of the queue."
|
|
(set-buffer (tq-buffer tq))
|
|
(if (= 0 (buffer-size)) ()
|
|
(if (tq-queue-empty tq)
|
|
(let ((buf (generate-new-buffer "*spurious*")))
|
|
(copy-to-buffer buf (point-min) (point-max))
|
|
(delete-region (point-min) (point))
|
|
(pop-to-buffer buf nil)
|
|
(error "Spurious communication from process %s, see buffer %s"
|
|
(process-name (tq-process tq))
|
|
(buffer-name buf)))
|
|
(goto-char (point-min))
|
|
(if (re-search-forward (tq-queue-head-regexp tq) nil t)
|
|
(let ((answer (buffer-substring (point-min) (point))))
|
|
(delete-region (point-min) (point))
|
|
(unwind-protect
|
|
(condition-case nil
|
|
(funcall (tq-queue-head-fn tq)
|
|
(tq-queue-head-closure tq)
|
|
answer)
|
|
(error nil))
|
|
(tq-queue-pop tq))
|
|
(tq-process-buffer tq))))))
|
|
|
|
(provide 'tq)
|
|
|
|
;;; arch-tag: 65dea08c-4edd-4cde-83a5-e8a15b993b79
|
|
;;; tq.el ends here
|