lisp/talk.el

   1 ;;; talk.el --- allow several users to talk to each other through Emacs
   2
   3 ;; Copyright (C) 1995, 2001, 2002, 2003, 2004, 2005,
   4 ;;   2006, 2007 Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7 ;; Keywords: comm, frames
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; This is a multi-user talk package that runs in Emacs.
  29 ;; Use talk-connect to bring a new person into the conversation.
  30
  31 ;;; Code:
  32
  33 (defvar talk-display-alist nil
  34   "Alist of displays on which Emacs talk is now running.
  35 Each element has the form (DISPLAY FRAME BUFFER).")
  36
  37 ;;;###autoload
  38 (defun talk-connect (display)
  39   "Connect to display DISPLAY for the Emacs talk group."
  40   (interactive "sTalk to display: ")
  41   ;; Make sure we have an entry for the current display.
  42   (let ((mydisp (cdr (assq 'display (frame-parameters (selected-frame))))))
  43     (talk-add-display mydisp))
  44   ;; Make sure we have an entry for the specified display.
  45   (talk-add-display display)
  46   ;; Add the new buffers to all talk frames.
  47   (talk-update-buffers))
  48
  49 (defun talk-add-display (display)
  50   (let* ((elt (assoc display talk-display-alist))
  51          (name (concat "*talk-" display "*"))
  52          buffer frame)
  53     (if (not (and elt (frame-live-p (setq frame (nth 1 elt)))))
  54         (setq frame (make-frame-on-display display (list (cons 'name name)))))
  55     (if (not (and elt (buffer-name (get-buffer (setq buffer (nth 2 elt))))))
  56         (setq buffer (get-buffer-create name)))
  57     (setq talk-display-alist
  58           (cons (list display frame buffer) (delq elt talk-display-alist)))))
  59
  60 (defun talk-disconnect ()
  61   "Disconnect this display from the Emacs talk group."
  62   (interactive)
  63   (let* ((mydisp (cdr (assq 'display (frame-parameters (selected-frame)))))
  64          (elt (assoc mydisp talk-display-alist)))
  65     (delete-frame (nth 1 elt))
  66     (kill-buffer (nth 2 elt))
  67     (setq talk-display-alist (delq elt talk-display-alist))
  68     (talk-update-buffers)))
  69
  70 (defun talk-update-buffers ()
  71   "Update all the talk frames so that each shows all the talk buffers."
  72   (let ((tail talk-display-alist))
  73     (while tail
  74       (let ((frame (nth 1 (car tail)))
  75             (this-buffer (nth 2 (car tail)))
  76             (buffers
  77              (mapcar (function (lambda (elt) (nth 2 elt)))
  78                      talk-display-alist)))
  79         ;; Put this display's own talk buffer
  80         ;; at the front of the list.
  81         (setq buffers (cons this-buffer (delq this-buffer buffers)))
  82         (talk-split-up-frame frame buffers))
  83       (setq tail (cdr tail)))))
  84
  85 (defun talk-split-up-frame (frame buffers)
  86   "Split FRAME into equal-sized windows displaying the buffers in BUFFERS.
  87 Select the first of these windows, displaying the first of the buffers."
  88   (let ((lines-per-buffer (/ (frame-height frame) (length buffers)))
  89         (old-frame (selected-frame)))
  90     (unwind-protect
  91         (progn
  92           (select-frame frame)
  93           (select-window (frame-first-window frame))
  94           (delete-other-windows)
  95           (while (progn
  96                    (switch-to-buffer (car buffers))
  97                    (setq buffers (cdr buffers)))
  98             (split-window-vertically lines-per-buffer)
  99             (other-window 1))
 100           (select-window (frame-first-window frame)))
 101       (select-frame old-frame))))
 102
 103 (provide 'talk)
 104
 105 ;;; arch-tag: 7ab0ad88-1788-4886-a44c-ae685e6f8a1a
 106 ;;; talk.el ends here