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Diffstat (limited to 'lisp')
| -rw-r--r-- | lisp/tq.el | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/lisp/tq.el b/lisp/tq.el deleted file mode 100644 index 81a152f..0000000 --- a/lisp/tq.el +++ /dev/null @@ -1,171 +0,0 @@ -;;; tq.el --- utility to maintain a transaction queue - -;; Copyright (C) 1985, 1986, 1987, 1992, 2001, 2002, 2003, 2004, -;; 2005, 2006, 2007, 2008, 2009 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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>. - -;;; Commentary: - -;; This file manages receiving a stream asynchronously, parsing it -;; into transactions, and then calling the associated handler function -;; upon the completion of each transaction. - -;; Our basic structure is the queue/process/buffer triple. Each entry -;; of the queue part is a list of question, regexp, closure, and -;; function that is consed to the last element. - -;; A transaction queue may be created by calling `tq-create'. - -;; A request may be added to the queue by calling `tq-enqueue'. If -;; the `delay-question' argument is non-nil, we will wait to send the -;; question to the process until it has finished sending other input. -;; Otherwise, once a request is enqueued, we send the given question -;; immediately to the process. - -;; We then buffer bytes from the process until we see the regexp that -;; was provided in the call to `tq-enqueue'. Then we call the -;; provided function with the closure and the collected bytes. If we -;; have indicated that the question from the next transaction was not -;; sent immediately, send it at this point, awaiting the response. - -;;; Code: - -;;; Accessors - -;; This part looks like (queue . (process . buffer)) -(defun tq-queue (tq) (car tq)) -(defun tq-process (tq) (car (cdr tq))) -(defun tq-buffer (tq) (cdr (cdr tq))) - -;; The structure of `queue' is as follows -;; ((question regexp closure . fn) -;; <other queue entries>) -;; question: string to send to the process -(defun tq-queue-head-question (tq) (car (car (tq-queue tq)))) -;; regexp: regular expression that matches the end of a response from -;; the process -(defun tq-queue-head-regexp (tq) (car (cdr (car (tq-queue tq))))) -;; closure: additional data to pass to the function -(defun tq-queue-head-closure (tq) (car (cdr (cdr (car (tq-queue tq)))))) -;; fn: function to call upon receiving a complete response from the -;; process -(defun tq-queue-head-fn (tq) (cdr (cdr (cdr (car (tq-queue tq)))))) - -;; Determine whether queue is empty -(defun tq-queue-empty (tq) (not (tq-queue tq))) - -;;; Core functionality - -;;;###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))))))) - (buffer-disable-undo (tq-buffer tq)) - (set-process-filter process - `(lambda (proc string) - (tq-filter ',tq string))) - tq)) - -(defun tq-queue-add (tq question re closure fn) - (setcar tq (nconc (tq-queue tq) - (cons (cons question (cons re (cons closure fn))) nil))) - 'ok) - -(defun tq-queue-pop (tq) - (setcar tq (cdr (car tq))) - (let ((question (tq-queue-head-question tq))) - (condition-case nil - (process-send-string (tq-process tq) question) - (error nil))) - (null (car tq))) - -(defun tq-enqueue (tq question regexp closure fn &optional delay-question) - "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, which may contain additional data that FN -needs, 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. - -If DELAY-QUESTION is non-nil, delay sending this question until -the process has finished replying to any previous questions. -This produces more reliable results with some processes." - (let ((sendp (or (not delay-question) - (not (tq-queue tq))))) - (tq-queue-add tq (unless sendp question) regexp closure fn) - (when sendp - (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." - (let ((buffer (tq-buffer tq))) - (when (buffer-live-p buffer) - (with-current-buffer buffer - (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." - (let ((buffer (tq-buffer tq))) - (when (buffer-live-p buffer) - (set-buffer buffer) - (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 |