X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/83023647e0c1769ad958d0c87618955f04d6b618..b08b261e8b7aabbc3a7647e620728a6dbe973652:/lisp/emacs-lisp/tq.el

diff --git a/lisp/emacs-lisp/tq.el b/lisp/emacs-lisp/tq.el
index 4a5b155a55..917309e3b9 100644
--- a/lisp/emacs-lisp/tq.el
+++ b/lisp/emacs-lisp/tq.el
@@ -1,35 +1,56 @@
 ;;; tq.el --- utility to maintain a transaction queue
 
+;; Copyright (C) 1985, 1986, 1987, 1992 Free Software Foundation, Inc.
+
 ;; Author: Scott Draves <spot@cs.cmu.edu>
+;; Maintainer: FSF
 ;; Adapted-By: ESR
+;; Keywords: extensions
 
-;; Commentary:
- 
-;;; manages receiving a stream asynchronously, 
-;;; parsing it into transactions, and then calling
-;;; handler functions
+;; This file is part of GNU Emacs.
 
-;;; 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.
+;; 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.
 
-;;; Code:
+;; 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.
 
-(provide 'tq)
+;; 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.  PROCESS should be 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."
+  "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))))
+			`(lambda (proc string)
+			   (tq-filter '(, tq) string)))
     tq))
 
 ;;; accessors
@@ -47,27 +68,30 @@ or it may be connected to a tcp server on another machine."
 (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 TQ.  Send question to the process, and call FN
-with CLOSURE and and the answer, when it appears.  The end of the
-answer is identified by REGEXP."
+  "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 the process, and destroy the evidence."
+  "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."
-  (set-buffer (tq-buffer tq))
-  (goto-char (point-max))
-  (insert string)
-  (tq-process-buffer tq))
+  (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."
@@ -78,17 +102,22 @@ answer is identified by REGEXP."
 	  (copy-to-buffer buf (point-min) (point-max))
 	  (delete-region (point-min) (point))
 	  (pop-to-buffer buf nil)
-	  (error (concat "Spurious communication from process "
-			 (process-name (tq-process tq))
-			 ", see buffer *spurious*.")))
+	  (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))
-	    (funcall (tq-queue-head-fn tq)
-		     (tq-queue-head-closure tq)
-		     answer)
-	    (tq-queue-pop tq)
+	    (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)
+
 ;;; tq.el ends here