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2352 lines
78 KiB
EmacsLisp
2352 lines
78 KiB
EmacsLisp
;;; follow.el --- Minor mode, Synchronize windows showing the same buffer.
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;; Copyright (C) 1995, 1996, 1997, 1999 Free Software Foundation, Inc.
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;; Author: Anders Lindgren <andersl@andersl.com>
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;; Maintainer: Anders Lindgren <andersl@andersl.com>
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;; Created: 1995-05-25
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;; Keywords: display, window, minor-mode, convenience
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;; Last Changed: 1999-11-17
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;; This file is part of GNU Emacs.
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;; GNU Emacs is free software; you can redistribute it and/or modify
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;; it under the terms of the GNU General Public License as published by
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;; the Free Software Foundation; either version 2, or (at your option)
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;; any later version.
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;; GNU Emacs is distributed in the hope that it will be useful,
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;; but WITHOUT ANY WARRANTY; without even the implied warranty of
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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;; GNU General Public License for more details.
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;; You should have received a copy of the GNU General Public License
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;; along with GNU Emacs; see the file COPYING. If not, write to the
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;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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;; Boston, MA 02111-1307, USA.
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;;; Commentary:
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;;{{{ Documentation
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;; `Follow mode' is a minor mode for Emacs and XEmacs that
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;; combines windows into one tall virtual window.
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;;
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;; The feeling of a "virtual window" has been accomplished by the use
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;; of two major techniques:
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;;
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;; * The windows always displays adjacent sections of the buffer.
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;; This means that whenever one window is moved, all the
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;; others will follow. (Hence the name Follow Mode.)
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;;
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;; * Should the point (cursor) end up outside a window, another
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;; window displaying that point is selected, if possible. This
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;; makes it possible to walk between windows using normal cursor
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;; movement commands.
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;;
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;; Follow mode comes to its prime when a large screen and two
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;; side-by-side window are used. The user can, with the help of Follow
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;; mode, use two full-height windows as though they would have been
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;; one. Imagine yourself editing a large function, or section of text,
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;; and being able to use 144 lines instead of the normal 72... (your
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;; mileage may vary).
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;; To test this package, make sure `follow' is loaded, or will be
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;; autoloaded when activated (see below). Then do the following:
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;;
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;; * Find your favorite file (preferably a long one).
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;;
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;; * Resize Emacs so that it will be wide enough for two full size
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;; columns. Delete the other windows and split the window with
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;; the commands `C-x 1 C-x 3'.
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;;
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;; * Give the command:
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;; M-x follow-mode <RETURN>
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;;
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;; * Now the display should look something like (assuming the text "71"
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;; is on line 71):
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;;
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;; +----------+----------+
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;; |1 |73 |
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;; |2 |74 |
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;; |3 |75 |
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;; ... ...
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;; |71 |143 |
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;; |72 |144 |
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;; +----------+----------+
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;;
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;; As you can see, the right-hand window starts at line 73, the line
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;; immediately below the end of the left-hand window. As long as
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;; `follow-mode' is active, the two windows will follow eachother!
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;;
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;; * Play around and enjoy! Scroll one window and watch the other.
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;; Jump to the beginning or end. Press `Cursor down' at the last
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;; line of the left-hand window. Enter new lines into the
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;; text. Enter long lines spanning several lines, or several
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;; windows.
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;;
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;; * Should you find `Follow' mode annoying, just type
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;; M-x follow-mode <RETURN>
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;; to turn it off.
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;; The command `follow-delete-other-windows-and-split' maximises the
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;; visible area of the current buffer.
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;;
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;; I recommend adding it, and `follow-mode', to hotkeys in the global
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;; key map. To do so, add the following lines (replacing `[f7]' and
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;; `[f8]' with your favorite keys) to the init file:
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;;
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;; (global-set-key [f8] 'follow-mode)
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;; (global-set-key [f7] 'follow-delete-other-windows-and-split)
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;; There exists two system variables that controls the appearence of
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;; lines that are wider than the window containing them. The default
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;; is to truncate long lines whenever a window isn't as wide as the
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;; frame.
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;;
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;; To make sure lines are never truncated, please place the following
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;; lines in your init file:
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;;
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;; (setq truncate-lines nil)
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;; (setq truncate-partial-width-windows nil)
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;; Since the display of XEmacs is pixel-oriented, a line could be
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;; clipped in half at the bottom of the window.
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;;
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;; To make XEmacs avoid clipping (normal) lines, please place the
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;; following line in your init-file:
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;;
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;; (setq pixel-vertical-clip-threshold 30)
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;; The correct way to cofigurate Follow mode, or any other mode for
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;; that matter, is to create one (or more) function that does
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;; whatever you would like to do. The function is then added to
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;; a hook.
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;;
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;; When `Follow' mode is activated, functions stored in the hook
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;; `follow-mode-hook' are called. When it is deactivated
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;; `follow-mode-off-hook' is runed.
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;;
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;; The keymap `follow-key-map' contains key bindings activated by
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;; `follow-mode'.
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;;
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;; Example:
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;; (add-hook 'follow-mode-hook 'my-follow-mode-hook)
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;;
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;; (defun my-follow-mode-hook ()
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;; (define-key follow-mode-map "\C-ca" 'your-favorite-function)
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;; (define-key follow-mode-map "\C-cb" 'another-function))
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;; Usage:
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;;
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;; To activate issue the command "M-x follow-mode"
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;; and press return. To deactivate, do it again.
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;;
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;; The following is a list of commands useful when follow-mode is active.
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;;
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;; follow-scroll-up C-c . C-v
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;; Scroll text in a Follow Mode window chain up.
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;;
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;; follow-scroll-down C-c . v
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;; Like `follow-scroll-up', but in the other direction.
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;;
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;; follow-delete-other-windows-and-split C-c . 1
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;; Maximise the visible area of the current buffer,
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;; and enter Follow Mode. This is a very convenient
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;; way to start Follow Mode, hence it is recomended
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;; that this command is added to the global keymap.
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;;
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;; follow-recenter C-c . C-l
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;; Place the point in the center of the middle window,
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;; or a specified number of lines from either top or bottom.
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;;
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;; follow-switch-to-buffer C-c . b
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;; Switch buffer in all windows displaying the current buffer
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;; in this frame.
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;;
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;; follow-switch-to-buffer-all C-c . C-b
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;; Switch buffer in all windows in the active frame.
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;;
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;; follow-switch-to-current-buffer-all
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;; Show the current buffer in all windows on the current
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;; frame and turn on `follow-mode'.
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;;
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;; follow-first-window C-c . <
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;; Select the first window in the frame showing the same buffer.
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;;
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;; follow-last-window C-c . >
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;; Select the last window in the frame showing the same buffer.
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;;
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;; follow-next-window C-c . n
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;; Select the next window in the frame showing the same buffer.
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;;
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;; follow-previous-window C-c . p
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;; Select the previous window showing the same buffer.
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;; Well, it seems ok, but what if I really want to look at two different
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;; positions in the text? Here are two simple methods to use:
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;;
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;; 1) Use multiple frames; `follow' mode only affects windows displayed
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;; in the same frame. (My apoligies to you who can't use frames.)
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;;
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;; 2) Bind `follow-mode' to key so you can turn it off whenever
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;; you want to view two locations. Of course, `follow' mode can
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;; be reactivated by hitting the same key again.
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;;
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;; Example from my ~/.emacs:
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;; (global-set-key [f8] 'follow-mode)
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;; Implementation:
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;;
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;; In an ideal world, follow mode would have been implemented in the
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;; kernel of the display routines, making sure that the windows (using
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;; follow mode) ALWAYS are aligned. On planet earth, however, we must
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;; accept a solution where we ALMOST ALWAYS can make sure that the
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;; windows are aligned.
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;;
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;; Follow mode does this in three places:
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;; 1) After each user command.
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;; 2) After a process output has been perfomed.
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;; 3) When a scrollbar has been moved.
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;;
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;; This will cover most situations. (Let me know if there are other
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;; situations that should be covered.)
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;;
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;; Note that only the selected window is checked, for the reason of
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;; efficiency and code complexity. (I.e. it is possible to make a
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;; non-selected windows unaligned. It will, however, pop right back
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;; when it is selected.)
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;;}}}
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;;; Code:
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;;{{{ Preliminaries
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;; Make the compiler shut up!
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;; There are two strategies:
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;; 1) Shut warnings off completely.
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;; 2) Handle each warning separately.
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;;
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;; Since I would like to see real errors, I've selected the latter
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;; method.
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;;
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;; The problem with undefined variables and functions has been solved
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;; by using `set', `symbol-value' and `symbol-function' rather than
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;; `setq' and direct references to variables and functions.
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;;
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;; For example:
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;; (if (boundp 'foo) ... (symbol-value 'foo) )
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;; (set 'foo ...) <-- XEmacs doesn't fall for this one.
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;; (funcall (symbol-function 'set) 'bar ...)
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;;
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;; Note: When this file is interpreted, `eval-when-compile' is
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;; evaluted. Since it doesn't hurt to evaluate it, but it is a bit
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;; annoying, we test if the byte-compiler has been loaded. This can,
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;; of course, lead to some occasional unintended evaluation...
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;;
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;; Should someone come up with a better solution, please let me
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;; know.
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(eval-when-compile
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(if (or (featurep 'bytecomp)
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(featurep 'byte-compile))
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(cond ((string-match "XEmacs" emacs-version)
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;; Make XEmacs shut up! I'm using standard Emacs
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;; functions, they are NOT obsolete!
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(if (eq (get 'force-mode-line-update 'byte-compile)
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'byte-compile-obsolete)
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(put 'force-mode-line-update 'byte-compile 'nil))
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(if (eq (get 'frame-first-window 'byte-compile)
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'byte-compile-obsolete)
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(put 'frame-first-window 'byte-compile 'nil))))))
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;;}}}
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;;{{{ Variables
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(defgroup follow nil
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"Synchronize windows showing the same buffer."
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:prefix "follow-"
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:group 'windows
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:group 'convenience)
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(defvar follow-mode nil
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"Variable indicating if Follow mode is active.")
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(defcustom follow-mode-hook nil
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"*Hooks to run when follow-mode is turned on."
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:type 'hook
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:group 'follow)
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(defcustom follow-mode-off-hook nil
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"*Hooks to run when follow-mode is turned off."
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:type 'hook
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:group 'follow)
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(defvar follow-mode-map nil
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"*Minor mode keymap for Follow mode.")
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(defcustom follow-mode-line-text " Follow"
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"*Text shown in the mode line when Follow mode is active.
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Defaults to \" Follow\". Examples of other values
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are \" Fw\", or simply \"\"."
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:type 'string
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:group 'follow)
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(defcustom follow-auto nil
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"*Non-nil activates Follow mode whenever a file is loaded."
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:type 'boolean
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:group 'follow)
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(defcustom follow-mode-prefix "\C-c."
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"*Prefix key to use for follow commands in Follow mode.
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The value of this variable is checked as part of loading Follow mode.
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After that, changing the prefix key requires manipulating keymaps."
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:type 'string
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:group 'follow)
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(defcustom follow-intercept-processes
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(fboundp 'start-process)
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"*When non-nil, Follow Mode will monitor process output."
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:type 'boolean
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:group 'follow)
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(defvar follow-emacs-version-xemacs-p
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(string-match "XEmacs" emacs-version)
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"Non-nil when running under XEmacs.")
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(defvar follow-avoid-tail-recenter-p
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(not follow-emacs-version-xemacs-p)
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"*When non-nil, patch emacs so that tail windows won't be recentered.
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A \"tail window\" is a window that displays only the end of
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the buffer. Normally it is practical for the user that empty
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windows are recentered automatically. However, when using
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Follow Mode it breaks the display when the end is displayed
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in a window \"above\" the last window. This is for
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example the case when displaying a short page in info.
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Must be set before Follow Mode is loaded.
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Please note that it is not possible to fully prevent Emacs from
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recentering empty windows. Please report if you find a repeatable
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situation in which Emacs recenters empty windows.
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XEmacs, as of 19.12, does not recenter windows, good!")
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(defvar follow-cache-command-list
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'(next-line previous-line forward-char backward-char)
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"List of commands that don't require recalculation.
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In order to be able to use the cache, a command should not change the
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contents of the buffer, nor should it change selected window or current
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buffer.
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The commands in this list are checked at load time.
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To mark other commands as suitable for caching, set the symbol
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property `follow-mode-use-cache' to non-nil.")
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(defvar follow-debug nil
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"*Non-nil when debugging Follow mode.")
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;; Internal variables:
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(defvar follow-internal-force-redisplay nil
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"True when Follow mode should redisplay the windows.")
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(defvar follow-process-filter-alist '()
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"The original filters for processes intercepted by Follow mode.")
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(defvar follow-active-menu nil
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"The menu visible when Follow mode is active.")
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(defvar follow-deactive-menu nil
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"The menu visible when Follow mode is deactivated.")
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(defvar follow-inside-post-command-hook nil
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"Non-nil when inside Follow modes `post-command-hook'.
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Used by `follow-window-size-change'.")
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(defvar follow-windows-start-end-cache nil
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"Cache used by `follow-window-start-end'.")
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;;}}}
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;;{{{ Bug report
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(eval-when-compile (require 'reporter))
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(defun follow-submit-feedback ()
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"Submit feedback on Follow mode to the author: andersl@andersl.com"
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(interactive)
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(require 'reporter)
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(and (y-or-n-p "Do you really want to submit a report on Follow mode? ")
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(reporter-submit-bug-report
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"Anders Lindgren <andersl@andersl.com>"
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"follow.el"
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'(post-command-hook
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post-command-idle-hook
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pre-command-hook
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window-size-change-functions
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window-scroll-functions
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follow-mode-hook
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follow-mode-off-hook
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follow-auto
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follow-intercept-processes
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follow-avoid-tail-recenter-p
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follow-process-filter-alist)
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nil
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nil
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(concat
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"Hi Anders!\n\n"
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"(I have read the section on how to report bugs in the "
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"Emacs manual.)\n\n"
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"Even though I know you are busy, I thought you might "
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"want to know...\n\n"))))
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;;}}}
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;;{{{ Debug messages
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;; This inline function must be as small as possible!
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;; Maybe we should define a macro that expands to nil if
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;; the variable is not set.
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(defsubst follow-debug-message (&rest args)
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"Like message, but only active when `follow-debug' is non-nil."
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(if (and (boundp 'follow-debug) follow-debug)
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(apply 'message args)))
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;;}}}
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;;{{{ Keymap/Menu
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;;; Define keys for the follow-mode minor mode map and replace some
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;;; functions in the global map. All `follow' mode special functions
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;;; can be found on (the somewhat cumbersome) "C-c . <key>"
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;;; (Control-C dot <key>). (As of Emacs 19.29 the keys
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;;; C-c <punctuation character> are reserved for minor modes.)
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;;;
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;;; To change the prefix, redefine `follow-mode-prefix' before
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;;; `follow' is loaded, or see the section on `follow-mode-hook'
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;;; above for an example of how to bind the keys the way you like.
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;;;
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;;; Please note that the keymap is defined the first time this file is
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;;; loaded. Also note that the only legal way to manipulate the
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;;; keymap is to use `define-key'. Don't change it using `setq' or
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;;; similar!
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(if follow-mode-map
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nil
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(setq follow-mode-map (make-sparse-keymap))
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(let ((map (make-sparse-keymap)))
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(define-key map "\C-v" 'follow-scroll-up)
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(define-key map "\M-v" 'follow-scroll-down)
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(define-key map "v" 'follow-scroll-down)
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(define-key map "1" 'follow-delete-other-windows-and-split)
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(define-key map "b" 'follow-switch-to-buffer)
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(define-key map "\C-b" 'follow-switch-to-buffer-all)
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(define-key map "\C-l" 'follow-recenter)
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(define-key map "<" 'follow-first-window)
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(define-key map ">" 'follow-last-window)
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(define-key map "n" 'follow-next-window)
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(define-key map "p" 'follow-previous-window)
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(define-key follow-mode-map follow-mode-prefix map)
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;; Replace the standard `end-of-buffer', when in Follow Mode. (I
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;; don't see the point in trying to replace every function that
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;; could be enhanced in Follow mode. End-of-buffer is a special
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;; case since it is very simple to define and it greatly enhances
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;; the look and feel of Follow mode.)
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;;
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;; (The function `substitute-key-definition' does not work
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;; in all versions of Emacs.)
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(mapcar
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(function
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(lambda (pair)
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(let ((old (car pair))
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(new (cdr pair)))
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(mapcar (function (lambda (key)
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(define-key follow-mode-map key new)))
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(where-is-internal old global-map)))))
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'((end-of-buffer . follow-end-of-buffer)
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(fkey-end-of-buffer . follow-end-of-buffer)))
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;;;
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;;; The menu.
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;;;
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(if (not follow-emacs-version-xemacs-p)
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;;
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;; Emacs
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;;
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(let ((menumap (funcall (symbol-function 'make-sparse-keymap)
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"Follow"))
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(count 0)
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id)
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(mapcar
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(function
|
|
(lambda (item)
|
|
(setq id
|
|
(or (cdr item)
|
|
(progn
|
|
(setq count (+ count 1))
|
|
(intern (format "separator-%d" count)))))
|
|
(define-key menumap (vector id) item)
|
|
(or (eq id 'follow-mode)
|
|
(put id 'menu-enable 'follow-mode))))
|
|
;; In reverse order:
|
|
'(("Toggle Follow mode" . follow-mode)
|
|
("--")
|
|
("Recenter" . follow-recenter)
|
|
("--")
|
|
("Previous Window" . follow-previous-window)
|
|
("Next Windows" . follow-next-window)
|
|
("Last Window" . follow-last-window)
|
|
("First Window" . follow-first-window)
|
|
("--")
|
|
("Switch To Buffer (all windows)"
|
|
. follow-switch-to-buffer-all)
|
|
("Switch To Buffer" . follow-switch-to-buffer)
|
|
("--")
|
|
("Delete Other Windows and Split"
|
|
. follow-delete-other-windows-and-split)
|
|
("--")
|
|
("Scroll Down" . follow-scroll-down)
|
|
("Scroll Up" . follow-scroll-up)))
|
|
|
|
;; If there is a `tools' meny, we use it. However, we can't add a
|
|
;; minor-mode specific item to it (it's broken), so we make the
|
|
;; contents ghosted when not in use, and add ourselves to the
|
|
;; global map. If no `tools' menu is present, just make a
|
|
;; top-level menu visible when the mode is activated.
|
|
|
|
(let ((tools-map (lookup-key (current-global-map) [menu-bar tools]))
|
|
(last nil))
|
|
(if (sequencep tools-map)
|
|
(progn
|
|
;; Find the last entry in the menu and store it in `last'.
|
|
(mapcar (function
|
|
(lambda (x)
|
|
(setq last (or (cdr-safe
|
|
(cdr-safe
|
|
(cdr-safe x)))
|
|
last))))
|
|
tools-map)
|
|
(if last
|
|
(progn
|
|
(funcall (symbol-function 'define-key-after)
|
|
tools-map [separator-follow] '("--") last)
|
|
(funcall (symbol-function 'define-key-after)
|
|
tools-map [follow] (cons "Follow" menumap)
|
|
'separator-follow))
|
|
;; Didn't find the last item, Adding to the top of
|
|
;; tools. (This will probably never happend...)
|
|
(define-key (current-global-map) [menu-bar tools follow]
|
|
(cons "Follow" menumap))))
|
|
;; No tools menu, add "Follow" to the menubar.
|
|
(define-key follow-mode-map [menu-bar follow]
|
|
(cons "Follow" menumap)))))
|
|
|
|
;;
|
|
;; XEmacs.
|
|
;;
|
|
|
|
;; place the menu in the `Tools' menu.
|
|
(let ((menu '("Follow"
|
|
:filter follow-menu-filter
|
|
["Scroll Up" follow-scroll-up t]
|
|
["Scroll Down" follow-scroll-down t]
|
|
["Delete Other Windows and Split"
|
|
follow-delete-other-windows-and-split t]
|
|
["Switch To Buffer" follow-switch-to-buffer t]
|
|
["Switch To Buffer (all windows)"
|
|
follow-switch-to-buffer-all t]
|
|
["First Window" follow-first-window t]
|
|
["Last Window" follow-last-window t]
|
|
["Next Windows" follow-next-window t]
|
|
["Previous Window" follow-previous-window t]
|
|
["Recenter" follow-recenter t]
|
|
["Deactivate" follow-mode t])))
|
|
|
|
;; Why not just `(set-buffer-menubar current-menubar)'? The
|
|
;; question is a very good question. The reason is that under
|
|
;; Emacs, neither `set-buffer-menubar' nor
|
|
;; `current-menubar' is defined, hence the byte-compiler will
|
|
;; warn.
|
|
(funcall (symbol-function 'set-buffer-menubar)
|
|
(symbol-value 'current-menubar))
|
|
(funcall (symbol-function 'add-submenu) '("Tools") menu))
|
|
|
|
;; When the mode is not activated, only one item is visible:
|
|
;; "Activate".
|
|
(defun follow-menu-filter (menu)
|
|
(if follow-mode
|
|
menu
|
|
'(["Activate " follow-mode t]))))))
|
|
|
|
|
|
;;; Register the follow mode keymap.
|
|
(or (assq 'follow-mode minor-mode-map-alist)
|
|
(setq minor-mode-map-alist
|
|
(cons (cons 'follow-mode follow-mode-map) minor-mode-map-alist)))
|
|
|
|
;;}}}
|
|
;;{{{ Cache
|
|
|
|
(let ((cmds follow-cache-command-list))
|
|
(while cmds
|
|
(put (car cmds) 'follow-mode-use-cache t)
|
|
(setq cmds (cdr cmds))))
|
|
|
|
;;}}}
|
|
|
|
;;{{{ The mode
|
|
|
|
;;;###autoload
|
|
(defun turn-on-follow-mode ()
|
|
"Turn on Follow mode. Please see the function `follow-mode'."
|
|
(interactive)
|
|
(follow-mode 1))
|
|
|
|
|
|
;;;###autoload
|
|
(defun turn-off-follow-mode ()
|
|
"Turn off Follow mode. Please see the function `follow-mode'."
|
|
(interactive)
|
|
(follow-mode -1))
|
|
|
|
|
|
;;;###autoload
|
|
(defun follow-mode (arg)
|
|
"Minor mode that combines windows into one tall virtual window.
|
|
|
|
The feeling of a \"virtual window\" has been accomplished by the use
|
|
of two major techniques:
|
|
|
|
* The windows always displays adjacent sections of the buffer.
|
|
This means that whenever one window is moved, all the
|
|
others will follow. (Hence the name Follow Mode.)
|
|
|
|
* Should the point (cursor) end up outside a window, another
|
|
window displaying that point is selected, if possible. This
|
|
makes it possible to walk between windows using normal cursor
|
|
movement commands.
|
|
|
|
Follow mode comes to its prime when used on a large screen and two
|
|
side-by-side window are used. The user can, with the help of Follow
|
|
mode, use two full-height windows as though they would have been
|
|
one. Imagine yourself editing a large function, or section of text,
|
|
and being able to use 144 lines instead of the normal 72... (your
|
|
mileage may vary).
|
|
|
|
To split one large window into two side-by-side windows, the commands
|
|
`\\[split-window-horizontally]' or \
|
|
`M-x follow-delete-other-windows-and-split' can be used.
|
|
|
|
Only windows displayed in the same frame follow each-other.
|
|
|
|
If the variable `follow-intercept-processes' is non-nil, Follow mode
|
|
will listen to the output of processes and redisplay accordingly.
|
|
\(This is the default.)
|
|
|
|
When Follow mode is switched on, the hook `follow-mode-hook'
|
|
is called. When turned off, `follow-mode-off-hook' is called.
|
|
|
|
Keys specific to Follow mode:
|
|
\\{follow-mode-map}"
|
|
(interactive "P")
|
|
(make-local-variable 'follow-mode)
|
|
(put 'follow-mode 'permanent-local t)
|
|
(let ((follow-mode-orig follow-mode))
|
|
(setq follow-mode
|
|
(if (null arg)
|
|
(not follow-mode)
|
|
(> (prefix-numeric-value arg) 0)))
|
|
(if (and follow-mode follow-intercept-processes)
|
|
(follow-intercept-process-output))
|
|
(cond ((and follow-mode (not follow-mode-orig)) ; On
|
|
;; XEmacs: If this is non-nil, the window will scroll before
|
|
;; the point will have a chance to get into the next window.
|
|
(if (boundp 'scroll-on-clipped-lines)
|
|
(set 'scroll-on-clipped-lines nil))
|
|
(force-mode-line-update)
|
|
(add-hook 'post-command-hook 'follow-post-command-hook t)
|
|
(if (boundp 'post-command-idle-hook)
|
|
(add-hook 'post-command-idle-hook
|
|
'follow-avoid-tail-recenter t))
|
|
(run-hooks 'follow-mode-hook))
|
|
|
|
((and (not follow-mode) follow-mode-orig) ; Off
|
|
(force-mode-line-update)
|
|
(run-hooks 'follow-mode-off-hook)))))
|
|
|
|
|
|
;; Register follow-mode as a minor mode.
|
|
|
|
(if (fboundp 'add-minor-mode)
|
|
;; XEmacs
|
|
(funcall (symbol-function 'add-minor-mode)
|
|
'follow-mode 'follow-mode-line-text)
|
|
(or (assq 'follow-mode minor-mode-alist)
|
|
(setq minor-mode-alist
|
|
(cons '(follow-mode follow-mode-line-text) minor-mode-alist))))
|
|
|
|
;;}}}
|
|
;;{{{ Find file hook
|
|
|
|
;; This will start follow-mode whenever a new file is loaded, if
|
|
;; the variable `follow-auto' is non-nil.
|
|
|
|
(add-hook 'find-file-hooks 'follow-find-file-hook t)
|
|
|
|
(defun follow-find-file-hook ()
|
|
"Find-file hook for Follow Mode. See the variable `follow-auto'."
|
|
(if follow-auto (follow-mode t)))
|
|
|
|
;;}}}
|
|
|
|
;;{{{ User functions
|
|
|
|
;;;
|
|
;;; User functions usable when in Follow mode.
|
|
;;;
|
|
|
|
;;{{{ Scroll
|
|
|
|
;; `scroll-up' and `-down', but for windows in Follow Mode.
|
|
;;
|
|
;; Almost like the real thing, excpet when the cursor ends up outside
|
|
;; the top or bottom... In our case however, we end up outside the
|
|
;; window and hence we are recenterd. Should we let `recenter' handle
|
|
;; the point position we would never leave the selected window. To do
|
|
;; it ourselves we would need to do our own redisplay, which is easier
|
|
;; said than done. (Why didn't I do a real display abstraction from
|
|
;; the beginning?)
|
|
;;
|
|
;; We must sometimes set `follow-internal-force-redisplay', otherwise
|
|
;; our post-command-hook will move our windows back into the old
|
|
;; position... (This would also be corrected if we would have had a
|
|
;; good redisplay abstraction.)
|
|
|
|
(defun follow-scroll-up (&optional arg)
|
|
"Scroll text in a Follow Mode window chain up.
|
|
|
|
If called with no ARG, the `next-screen-context-lines' last lines of
|
|
the bottom window in the chain will be visible in the top window.
|
|
|
|
If called with an argument, scroll ARG lines up.
|
|
Negative ARG means scroll downward.
|
|
|
|
Works like `scroll-up' when not in Follow Mode."
|
|
(interactive "P")
|
|
(cond ((not (and (boundp 'follow-mode) follow-mode))
|
|
(scroll-up arg))
|
|
(arg
|
|
(save-excursion (scroll-up arg))
|
|
(setq follow-internal-force-redisplay t))
|
|
(t
|
|
(let* ((windows (follow-all-followers))
|
|
(end (window-end (car (reverse windows)))))
|
|
(if (eq end (point-max))
|
|
(signal 'end-of-buffer nil)
|
|
(select-window (car windows))
|
|
;; `window-end' might return nil.
|
|
(if end
|
|
(goto-char end))
|
|
(vertical-motion (- next-screen-context-lines))
|
|
(set-window-start (car windows) (point)))))))
|
|
|
|
|
|
(defun follow-scroll-down (&optional arg)
|
|
"Scroll text in a Follow Mode window chain down.
|
|
|
|
If called with no ARG, the `next-screen-context-lines' top lines of
|
|
the top window in the chain will be visible in the bottom window.
|
|
|
|
If called with an argument, scroll ARG lines down.
|
|
Negative ARG means scroll upward.
|
|
|
|
Works like `scroll-up' when not in Follow Mode."
|
|
(interactive "P")
|
|
(cond ((not (and (boundp 'follow-mode) follow-mode))
|
|
(scroll-up arg))
|
|
(arg
|
|
(save-excursion (scroll-down arg)))
|
|
(t
|
|
(let* ((windows (follow-all-followers))
|
|
(win (car (reverse windows)))
|
|
(start (window-start (car windows))))
|
|
(if (eq start (point-min))
|
|
(signal 'beginning-of-buffer nil)
|
|
(select-window win)
|
|
(goto-char start)
|
|
(vertical-motion (- (- (window-height win)
|
|
1
|
|
next-screen-context-lines)))
|
|
(set-window-start win (point))
|
|
(goto-char start)
|
|
(vertical-motion (- next-screen-context-lines 1))
|
|
(setq follow-internal-force-redisplay t))))))
|
|
|
|
;;}}}
|
|
;;{{{ Buffer
|
|
|
|
;;;###autoload
|
|
(defun follow-delete-other-windows-and-split (&optional arg)
|
|
"Create two side by side windows and enter Follow Mode.
|
|
|
|
Execute this command to display as much as possible of the text
|
|
in the selected window. All other windows, in the current
|
|
frame, are deleted and the selected window is split in two
|
|
side-by-side windows. Follow Mode is activated, hence the
|
|
two windows always will display two successive pages.
|
|
\(If one window is moved, the other one will follow.)
|
|
|
|
If ARG is positive, the leftmost window is selected. If it negative,
|
|
the rightmost is selected. If ARG is nil, the leftmost window is
|
|
selected if the original window is the first one in the frame.
|
|
|
|
To bind this command to a hotkey, place the following line
|
|
in your `~/.emacs' file, replacing [f7] by your favourite key:
|
|
(global-set-key [f7] 'follow-delete-other-windows-and-split)"
|
|
(interactive "P")
|
|
(let ((other (or (and (null arg)
|
|
(not (eq (selected-window)
|
|
(frame-first-window (selected-frame)))))
|
|
(and arg
|
|
(< (prefix-numeric-value arg) 0))))
|
|
(start (window-start)))
|
|
(delete-other-windows)
|
|
(split-window-horizontally)
|
|
(if other
|
|
(progn
|
|
(other-window 1)
|
|
(set-window-start (selected-window) start)
|
|
(setq follow-internal-force-redisplay t)))
|
|
(follow-mode 1)))
|
|
|
|
(defun follow-switch-to-buffer (buffer)
|
|
"Show BUFFER in all windows in the current Follow Mode window chain."
|
|
(interactive "BSwitch to Buffer: ")
|
|
(let ((orig-window (selected-window))
|
|
(windows (follow-all-followers)))
|
|
(while windows
|
|
(select-window (car windows))
|
|
(switch-to-buffer buffer)
|
|
(setq windows (cdr windows)))
|
|
(select-window orig-window)))
|
|
|
|
|
|
(defun follow-switch-to-buffer-all (&optional buffer)
|
|
"Show BUFFER in all windows on this frame.
|
|
Defaults to current buffer."
|
|
(interactive (list (read-buffer "Switch to Buffer: "
|
|
(current-buffer))))
|
|
(or buffer (setq buffer (current-buffer)))
|
|
(let ((orig-window (selected-window)))
|
|
(walk-windows
|
|
(function
|
|
(lambda (win)
|
|
(select-window win)
|
|
(switch-to-buffer buffer))))
|
|
(select-window orig-window)
|
|
(follow-redisplay)))
|
|
|
|
|
|
(defun follow-switch-to-current-buffer-all ()
|
|
"Show current buffer in all windows on this frame, and enter Follow Mode.
|
|
|
|
To bind this command to a hotkey place the following line
|
|
in your `~/.emacs' file:
|
|
(global-set-key [f7] 'follow-switch-to-current-buffer-all)"
|
|
(interactive)
|
|
(or (and (boundp 'follow-mode) follow-mode)
|
|
(follow-mode 1))
|
|
(follow-switch-to-buffer-all))
|
|
|
|
;;}}}
|
|
;;{{{ Movement
|
|
|
|
;; Note, these functions are not very useful, atleast not unless you
|
|
;; rebind the rather cumbersome key sequence `C-c . p'.
|
|
|
|
(defun follow-next-window ()
|
|
"Select the next window showing the same buffer."
|
|
(interactive)
|
|
(let ((succ (cdr (follow-split-followers (follow-all-followers)))))
|
|
(if succ
|
|
(select-window (car succ))
|
|
(error "%s" "No more windows"))))
|
|
|
|
|
|
(defun follow-previous-window ()
|
|
"Select the previous window showing the same buffer."
|
|
(interactive)
|
|
(let ((pred (car (follow-split-followers (follow-all-followers)))))
|
|
(if pred
|
|
(select-window (car pred))
|
|
(error "%s" "No more windows"))))
|
|
|
|
|
|
(defun follow-first-window ()
|
|
"Select the first window in the frame showing the same buffer."
|
|
(interactive)
|
|
(select-window (car (follow-all-followers))))
|
|
|
|
|
|
(defun follow-last-window ()
|
|
"Select the last window in the frame showing the same buffer."
|
|
(interactive)
|
|
(select-window (car (reverse (follow-all-followers)))))
|
|
|
|
;;}}}
|
|
;;{{{ Redraw
|
|
|
|
(defun follow-recenter (&optional arg)
|
|
"Recenter the middle window around point.
|
|
Rearrange all other windows around the middle window.
|
|
|
|
With a positive argument, place the current line ARG lines
|
|
from the top. With a negative, place it -ARG lines from the
|
|
bottom."
|
|
(interactive "P")
|
|
(if arg
|
|
(let ((p (point))
|
|
(arg (prefix-numeric-value arg)))
|
|
(if (>= arg 0)
|
|
;; Recenter relative to the top.
|
|
(progn
|
|
(follow-first-window)
|
|
(goto-char p)
|
|
(recenter arg))
|
|
;; Recenter relative to the bottom.
|
|
(follow-last-window)
|
|
(goto-char p)
|
|
(recenter arg)
|
|
;; Otherwise, our post-command-hook will move the window
|
|
;; right back.
|
|
(setq follow-internal-force-redisplay t)))
|
|
;; Recenter in the middle.
|
|
(let* ((dest (point))
|
|
(windows (follow-all-followers))
|
|
(win (nth (/ (- (length windows) 1) 2) windows)))
|
|
(select-window win)
|
|
(goto-char dest)
|
|
(recenter)
|
|
;;(setq follow-internal-force-redisplay t)
|
|
)))
|
|
|
|
|
|
(defun follow-redraw ()
|
|
"Arrange windows displaying the same buffer in successor order.
|
|
This function can be called even if the buffer is not in Follow mode.
|
|
|
|
Hopefully, there should be no reason to call this function when in
|
|
Follow mode since the windows should always be aligned."
|
|
(interactive)
|
|
(sit-for 0)
|
|
(follow-redisplay))
|
|
|
|
;;}}}
|
|
;;{{{ End of buffer
|
|
|
|
(defun follow-end-of-buffer (&optional arg)
|
|
"Move point to the end of the buffer, Follow Mode style.
|
|
|
|
If the end is not visible, it will be displayed in the last possible
|
|
window in the Follow Mode window chain.
|
|
|
|
The mark is left at the previous position. With arg N, put point N/10
|
|
of the way from the true end."
|
|
(interactive "P")
|
|
(let ((followers (follow-all-followers))
|
|
(pos (point)))
|
|
(cond (arg
|
|
(select-window (car (reverse followers))))
|
|
((follow-select-if-end-visible
|
|
(follow-windows-start-end followers)))
|
|
(t
|
|
(select-window (car (reverse followers)))))
|
|
(goto-char pos)
|
|
(end-of-buffer arg)))
|
|
|
|
;;}}}
|
|
|
|
;;}}}
|
|
|
|
;;{{{ Display
|
|
|
|
;;;; The display routines
|
|
|
|
;;{{{ Information gathering functions
|
|
|
|
(defun follow-all-followers (&optional testwin)
|
|
"Return all windows displaying the same buffer as the TESTWIN.
|
|
The list contains only windows displayed in the same frame as TESTWIN.
|
|
If TESTWIN is nil the selected window is used."
|
|
(or (and testwin (window-live-p testwin))
|
|
(setq testwin (selected-window)))
|
|
(let* ((top (frame-first-window (window-frame testwin)))
|
|
(win top)
|
|
(done nil)
|
|
(windows '())
|
|
(buffer (window-buffer testwin)))
|
|
(while (and (not done) win)
|
|
(if (eq (window-buffer win) buffer)
|
|
(setq windows (cons win windows)))
|
|
(setq win (next-window win 'not))
|
|
(if (eq win top)
|
|
(setq done t)))
|
|
(nreverse windows)))
|
|
|
|
|
|
(defun follow-split-followers (windows &optional win)
|
|
"Split the WINDOWS into the sets: predecessors and successors.
|
|
Return `(PRED . SUCC)' where `PRED' and `SUCC' are ordered starting
|
|
from the selected window."
|
|
(or win
|
|
(setq win (selected-window)))
|
|
(let ((pred '()))
|
|
(while (not (eq (car windows) win))
|
|
(setq pred (cons (car windows) pred))
|
|
(setq windows (cdr windows)))
|
|
(cons pred (cdr windows))))
|
|
|
|
|
|
;; This function is optimized function for speed!
|
|
|
|
(defun follow-calc-win-end (&optional win)
|
|
"Calculate the presumed window end for WIN.
|
|
|
|
Actually, the position returned is the start of the next
|
|
window, normally is the end plus one.
|
|
|
|
If WIN is nil, the selected window is used.
|
|
|
|
Returns (end-pos end-of-buffer-p)"
|
|
(if follow-emacs-version-xemacs-p
|
|
;; XEmacs can calculate the end of the window by using
|
|
;; the 'guarantee options. GOOD!
|
|
(let ((end (window-end win t)))
|
|
(if (= end (funcall (symbol-function 'point-max)
|
|
(window-buffer win)))
|
|
(list end t)
|
|
(list (+ end 1) nil)))
|
|
;; Emacs: We have to calculate the end by ourselves.
|
|
;; This code works on both XEmacs and Emacs, but now
|
|
;; that XEmacs has got custom-written code, this could
|
|
;; be optimized for Emacs.
|
|
(let ((orig-win (and win (selected-window)))
|
|
height
|
|
buffer-end-p)
|
|
(if win (select-window win))
|
|
(prog1
|
|
(save-excursion
|
|
(goto-char (window-start))
|
|
(setq height (- (window-height) 1))
|
|
(setq buffer-end-p
|
|
(if (bolp)
|
|
(not (= height (vertical-motion height)))
|
|
(save-restriction
|
|
;; Fix a mis-feature in `vertical-motion':
|
|
;; The start of the window is assumed to
|
|
;; coinside with the start of a line.
|
|
(narrow-to-region (point) (point-max))
|
|
(not (= height (vertical-motion height))))))
|
|
(list (point) buffer-end-p))
|
|
(if orig-win
|
|
(select-window orig-win))))))
|
|
|
|
|
|
;; Can't use `save-window-excursion' since it triggers a redraw.
|
|
(defun follow-calc-win-start (windows pos win)
|
|
"Calculate where WIN will start if the first in WINDOWS start at POS.
|
|
|
|
If WIN is nil the point below all windows is returned."
|
|
(let (start)
|
|
(while (and windows (not (eq (car windows) win)))
|
|
(setq start (window-start (car windows)))
|
|
(set-window-start (car windows) pos 'noforce)
|
|
(setq pos (car (inline (follow-calc-win-end (car windows)))))
|
|
(set-window-start (car windows) start 'noforce)
|
|
(setq windows (cdr windows)))
|
|
pos))
|
|
|
|
|
|
;; The result from `follow-windows-start-end' is cached when using
|
|
;; a handful simple commands, like cursor movement commands.
|
|
|
|
(defsubst follow-cache-valid-p (windows)
|
|
"Test if the cached value of `follow-windows-start-end' can be used.
|
|
Note that this handles the case when the cache has been set to nil."
|
|
(let ((res t)
|
|
(cache follow-windows-start-end-cache))
|
|
(while (and res windows cache)
|
|
(setq res (and (eq (car windows)
|
|
(car (car cache)))
|
|
(eq (window-start (car windows))
|
|
(car (cdr (car cache))))))
|
|
(setq windows (cdr windows))
|
|
(setq cache (cdr cache)))
|
|
(and res (null windows) (null cache))))
|
|
|
|
|
|
(defsubst follow-invalidate-cache ()
|
|
"Force `follow-windows-start-end' to recalculate the end of the window."
|
|
(setq follow-windows-start-end-cache nil))
|
|
|
|
|
|
;; Build a list of windows and their start and end positions.
|
|
;; Useful to avoid calculating start/end position whenever they are needed.
|
|
;; The list has the format:
|
|
;; ((Win Start End End-of-buffer-visible-p) ...)
|
|
|
|
;; Used to have a `save-window-excursion', but it obviously triggered
|
|
;; redraws of the display. Check if I used it for anything.
|
|
|
|
|
|
(defun follow-windows-start-end (windows)
|
|
"Builds a list of (WIN START END BUFFER-END-P) for every window in WINDOWS."
|
|
(if (follow-cache-valid-p windows)
|
|
follow-windows-start-end-cache
|
|
(let ((win-start-end '())
|
|
(orig-win (selected-window)))
|
|
(while windows
|
|
(select-window (car windows))
|
|
(setq win-start-end
|
|
(cons (cons (car windows)
|
|
(cons (window-start)
|
|
(follow-calc-win-end)))
|
|
win-start-end))
|
|
(setq windows (cdr windows)))
|
|
(select-window orig-win)
|
|
(setq follow-windows-start-end-cache (nreverse win-start-end))
|
|
follow-windows-start-end-cache)))
|
|
|
|
|
|
(defsubst follow-pos-visible (pos win win-start-end)
|
|
"Non-nil when POS is visible in WIN."
|
|
(let ((wstart-wend-bend (cdr (assq win win-start-end))))
|
|
(and (>= pos (car wstart-wend-bend))
|
|
(or (< pos (car (cdr wstart-wend-bend)))
|
|
(nth 2 wstart-wend-bend)))))
|
|
|
|
|
|
;; By `aligned' we mean that for all adjecent windows, the end of the
|
|
;; first is equal with the start of the successor. The first window
|
|
;; should start at a full screen line.
|
|
|
|
(defsubst follow-windows-aligned-p (win-start-end)
|
|
"Non-nil if the follower WINDOWS are aligned."
|
|
(let ((res t))
|
|
(save-excursion
|
|
(goto-char (window-start (car (car win-start-end))))
|
|
(if (bolp)
|
|
nil
|
|
(vertical-motion 0 (car (car win-start-end)))
|
|
(setq res (eq (point) (window-start (car (car win-start-end)))))))
|
|
(while (and res (cdr win-start-end))
|
|
;; At least two followers left
|
|
(setq res (eq (car (cdr (cdr (car win-start-end))))
|
|
(car (cdr (car (cdr win-start-end))))))
|
|
(setq win-start-end (cdr win-start-end)))
|
|
res))
|
|
|
|
|
|
;; Check if the point is visible in all windows. (So that
|
|
;; no one will be recentered.)
|
|
|
|
(defun follow-point-visible-all-windows-p (win-start-end)
|
|
"Non-nil when the window-point is visible in all windows."
|
|
(let ((res t))
|
|
(while (and res win-start-end)
|
|
(setq res (follow-pos-visible (window-point (car (car win-start-end)))
|
|
(car (car win-start-end))
|
|
win-start-end))
|
|
(setq win-start-end (cdr win-start-end)))
|
|
res))
|
|
|
|
|
|
;; Make sure WIN always starts at the beginning of an whole screen
|
|
;; line. If WIN is not aligned the start is updated which probably
|
|
;; will lead to a redisplay of the screen later on.
|
|
;;
|
|
;; This is used with the first window in a follow chain. The reason
|
|
;; is that we want to detect that the point is outside the window.
|
|
;; (Without the update, the start of the window will move as the
|
|
;; user presses BackSpace, and the other window redisplay routines
|
|
;; will move the start of the window in the wrong direction.)
|
|
|
|
(defun follow-update-window-start (win)
|
|
"Make sure that the start of WIN starts at a full screen line."
|
|
(save-excursion
|
|
(goto-char (window-start win))
|
|
(if (bolp)
|
|
nil
|
|
(vertical-motion 0 win)
|
|
(if (eq (point) (window-start win))
|
|
nil
|
|
(vertical-motion 1 win)
|
|
(set-window-start win (point) 'noforce)))))
|
|
|
|
;;}}}
|
|
;;{{{ Selection functions
|
|
|
|
;; Make a window in WINDOWS selected if it currently
|
|
;; is displaying the position DEST.
|
|
;;
|
|
;; We don't select a window if it just has been moved.
|
|
|
|
(defun follow-select-if-visible (dest win-start-end)
|
|
"Select and return a window, if DEST is visible in it.
|
|
Return the selected window."
|
|
(let ((win nil))
|
|
(while (and (not win) win-start-end)
|
|
;; Don't select a window that was just moved. This makes it
|
|
;; possible to later select the last window after a `end-of-buffer'
|
|
;; command.
|
|
(if (follow-pos-visible dest (car (car win-start-end)) win-start-end)
|
|
(progn
|
|
(setq win (car (car win-start-end)))
|
|
(select-window win)))
|
|
(setq win-start-end (cdr win-start-end)))
|
|
win))
|
|
|
|
|
|
;; Lets select a window showing the end. Make sure we only select it if it
|
|
;; it wasn't just moved here. (i.e. M-> shall not unconditionally place
|
|
;; the point in the selected window.)
|
|
;;
|
|
;; (Compability cludge: in Emacs `window-end' is equal to `point-max';
|
|
;; in XEmacs, it is equal to `point-max + 1'. Should I really bother
|
|
;; checking `window-end' now when I check `end-of-buffer' explicitly?)
|
|
|
|
(defun follow-select-if-end-visible (win-start-end)
|
|
"Select and return a window, if end is visible in it."
|
|
(let ((win nil))
|
|
(while (and (not win) win-start-end)
|
|
;; Don't select a window that was just moved. This makes it
|
|
;; possible to later select the last window after a `end-of-buffer'
|
|
;; command.
|
|
(if (and (eq (point-max) (nth 2 (car win-start-end)))
|
|
(nth 3 (car win-start-end))
|
|
;; `window-end' might return nil.
|
|
(let ((end (window-end (car (car win-start-end)))))
|
|
(and end
|
|
(eq (point-max) (min (point-max) end)))))
|
|
(progn
|
|
(setq win (car (car win-start-end)))
|
|
(select-window win)))
|
|
(setq win-start-end (cdr win-start-end)))
|
|
win))
|
|
|
|
|
|
;; Select a window that will display the point if the windows would
|
|
;; be redisplayed with the first window fixed. This is useful for
|
|
;; example when the user has pressed return at the bottom of a window
|
|
;; as the point is not visible in any window.
|
|
|
|
(defun follow-select-if-visible-from-first (dest windows)
|
|
"Select and return a window with DEST, if WINDOWS are redrawn from top."
|
|
(let ((win nil)
|
|
end-pos-end-p)
|
|
(save-excursion
|
|
(goto-char (window-start (car windows)))
|
|
;; Make sure the line start in the beginning of a real screen
|
|
;; line.
|
|
(vertical-motion 0 (car windows))
|
|
(if (< dest (point))
|
|
;; Above the start, not visible.
|
|
nil
|
|
;; At or below the start. Check the windows.
|
|
(save-window-excursion
|
|
(while (and (not win) windows)
|
|
(set-window-start (car windows) (point) 'noforce)
|
|
(setq end-pos-end-p (follow-calc-win-end (car windows)))
|
|
(goto-char (car end-pos-end-p))
|
|
;; Visible, if dest above end, or if eob is visible inside
|
|
;; the window.
|
|
(if (or (car (cdr end-pos-end-p))
|
|
(< dest (point)))
|
|
(setq win (car windows))
|
|
(setq windows (cdr windows)))))))
|
|
(if win
|
|
(select-window win))
|
|
win))
|
|
|
|
|
|
;;}}}
|
|
;;{{{ Redisplay
|
|
|
|
;; Redraw all the windows on the screen, starting with the top window.
|
|
;; The window used as as marker is WIN, or the selcted window if WIN
|
|
;; is nil.
|
|
|
|
(defun follow-redisplay (&optional windows win)
|
|
"Reposition the WINDOWS around WIN.
|
|
Should the point be too close to the roof we redisplay everything
|
|
from the top. WINDOWS should contain a list of windows to
|
|
redisplay, it is assumed that WIN is a member of the list.
|
|
Should WINDOWS be nil, the windows displaying the
|
|
same buffer as WIN, in the current frame, are used.
|
|
Should WIN be nil, the selected window is used."
|
|
(or win
|
|
(setq win (selected-window)))
|
|
(or windows
|
|
(setq windows (follow-all-followers win)))
|
|
(follow-downward windows (follow-calculate-first-window-start windows win)))
|
|
|
|
|
|
;; Redisplay a chain of windows. Start every window directly after the
|
|
;; end of the previous window, to make sure long lines are displayed
|
|
;; correctly.
|
|
|
|
(defun follow-downward (windows pos)
|
|
"Redisplay all WINDOWS starting at POS."
|
|
(while windows
|
|
(set-window-start (car windows) pos)
|
|
(setq pos (car (follow-calc-win-end (car windows))))
|
|
(setq windows (cdr windows))))
|
|
|
|
|
|
;;(defun follow-downward (windows pos)
|
|
;; "Redisplay all WINDOWS starting at POS."
|
|
;; (let (p)
|
|
;; (while windows
|
|
;; (setq p (window-point (car windows)))
|
|
;; (set-window-start (car windows) pos)
|
|
;; (set-window-point (car windows) (max p pos))
|
|
;; (setq pos (car (follow-calc-win-end (car windows))))
|
|
;; (setq windows (cdr windows)))))
|
|
|
|
|
|
;; Return the start of the first window.
|
|
;;
|
|
;; First, estimate the position. It the value is not perfect (i.e. we
|
|
;; have somewhere splited a line between windows) we try to enhance
|
|
;; the value.
|
|
;;
|
|
;; The guess is always perfect if no long lines is split between
|
|
;; windows.
|
|
;;
|
|
;; The worst case peformace of probably very bad, but it is very
|
|
;; unlikely that we ever will miss the correct start by more than one
|
|
;; or two lines.
|
|
|
|
(defun follow-calculate-first-window-start (windows &optional win start)
|
|
"Calculate the start of the first window.
|
|
|
|
WINDOWS is a chain of windows to work with. WIN is the window
|
|
to recenter around. It is assumed that WIN starts at position
|
|
START."
|
|
(or win
|
|
(setq win (selected-window)))
|
|
(or start
|
|
(setq start (window-start win)))
|
|
(let ((guess (follow-estimate-first-window-start windows win start)))
|
|
(if (car guess)
|
|
(cdr guess)
|
|
;; The guess wasn't exact, try to enhance it.
|
|
(let ((win-start (follow-calc-win-start windows (cdr guess) win)))
|
|
(cond ((= win-start start)
|
|
(follow-debug-message "exact")
|
|
(cdr guess))
|
|
((< win-start start)
|
|
(follow-debug-message "above")
|
|
(follow-calculate-first-window-start-from-above
|
|
windows (cdr guess) win start))
|
|
(t
|
|
(follow-debug-message "below")
|
|
(follow-calculate-first-window-start-from-below
|
|
windows (cdr guess) win start)))))))
|
|
|
|
|
|
;; `exact' is disabled due to XEmacs and fonts of variable
|
|
;; height.
|
|
(defun follow-estimate-first-window-start (windows win start)
|
|
"Estimate the position of the first window.
|
|
|
|
Returns (EXACT . POS). If EXACT is non-nil, POS is the starting
|
|
position of the first window. Otherwise it is a good guess."
|
|
(let ((pred (car (follow-split-followers windows win)))
|
|
(exact nil))
|
|
(save-excursion
|
|
(goto-char start)
|
|
;(setq exact (bolp))
|
|
(vertical-motion 0 win)
|
|
(while pred
|
|
(vertical-motion (- 1 (window-height (car pred))) (car pred))
|
|
(if (not (bolp))
|
|
(setq exact nil))
|
|
(setq pred (cdr pred)))
|
|
(cons exact (point)))))
|
|
|
|
|
|
;; Find the starting point, start at GUESS and search downward.
|
|
;; The returned point is always a point below GUESS.
|
|
|
|
(defun follow-calculate-first-window-start-from-above
|
|
(windows guess win start)
|
|
(save-excursion
|
|
(let ((done nil)
|
|
win-start
|
|
res)
|
|
(goto-char guess)
|
|
(while (not done)
|
|
(if (not (= (vertical-motion 1 (car windows)) 1))
|
|
;; Hit bottom! (Can we really do this?)
|
|
;; We'll keep it, since it ensures termination.
|
|
(progn
|
|
(setq done t)
|
|
(setq res (point-max)))
|
|
(setq win-start (follow-calc-win-start windows (point) win))
|
|
(if (>= win-start start)
|
|
(progn
|
|
(setq done t)
|
|
(setq res (point))))))
|
|
res)))
|
|
|
|
|
|
;; Find the starting point, start at GUESS and search upward. Return
|
|
;; a point on the same line as GUESS, or above.
|
|
;;
|
|
;; (Is this ever used? I must make sure it works just in case it is
|
|
;; ever called.)
|
|
|
|
(defun follow-calculate-first-window-start-from-below
|
|
(windows guess &optional win start)
|
|
(setq win (or win (selected-window)))
|
|
(setq start (or start (window-start win)))
|
|
(save-excursion
|
|
(let ((done nil)
|
|
win-start
|
|
res)
|
|
;; Always calculate what happend when no line is displayed in the first
|
|
;; window. (The `previous' res is needed below!)
|
|
(goto-char guess)
|
|
(vertical-motion 0 (car windows))
|
|
(setq res (point))
|
|
(while (not done)
|
|
(if (not (= (vertical-motion -1 (car windows)) -1))
|
|
;; Hit roof!
|
|
(progn
|
|
(setq done t)
|
|
(setq res (point-min)))
|
|
(setq win-start (follow-calc-win-start windows (point) win))
|
|
(cond ((= win-start start) ; Perfect match, use this value
|
|
(setq done t)
|
|
(setq res (point)))
|
|
((< win-start start) ; Walked to far, use preious result
|
|
(setq done t))
|
|
(t ; Store result for next iteration
|
|
(setq res (point))))))
|
|
res)))
|
|
|
|
;;}}}
|
|
;;{{{ Avoid tail recenter
|
|
|
|
;; This sets the window internal flag `force_start'. The effect is that
|
|
;; windows only displaying the tail isn't recentered.
|
|
;; Has to be called before every redisplay... (Great isn't it?)
|
|
;;
|
|
;; XEmacs doesn't recenter the tail, GOOD!
|
|
;;
|
|
;; A window displaying only the tail, is a windows whose
|
|
;; window-start position is equal to (point-max) of the buffer it
|
|
;; displays.
|
|
;;
|
|
;; This function is also added to `post-command-idle-hook', introduced
|
|
;; in Emacs 19.30. This is needed since the vaccine injected by the
|
|
;; call from `post-command-hook' only works until the next redisplay.
|
|
;; It is possible that the functions in the `post-command-idle-hook'
|
|
;; can cause a redisplay, and hence a new vaccine is needed.
|
|
;;
|
|
;; Sometimes, calling this function could actually cause a redisplay,
|
|
;; especially if it is placed in the debug filter section. I must
|
|
;; investigate this further...
|
|
|
|
(defun follow-avoid-tail-recenter (&rest rest)
|
|
"Make sure windows displaying the end of a buffer aren't recentered.
|
|
|
|
This is done by reading and rewriting the start positon of
|
|
non-first windows in Follow Mode."
|
|
(if follow-avoid-tail-recenter-p
|
|
(let* ((orig-buffer (current-buffer))
|
|
(top (frame-first-window (selected-frame)))
|
|
(win top)
|
|
(who '()) ; list of (buffer . frame)
|
|
start
|
|
pair) ; (buffer . frame)
|
|
;; If the only window in the frame is a minibuffer
|
|
;; window, `next-window' will never find it again...
|
|
(if (window-minibuffer-p top)
|
|
nil
|
|
(while ;; look, no body!
|
|
(progn
|
|
(setq start (window-start win))
|
|
(set-buffer (window-buffer win))
|
|
(setq pair (cons (window-buffer win) (window-frame win)))
|
|
(if (member pair who)
|
|
(if (and (boundp 'follow-mode) follow-mode
|
|
(eq (point-max) start))
|
|
;; Write the same window start back, but don't
|
|
;; set the NOFORCE flag.
|
|
(set-window-start win start))
|
|
(setq who (cons pair who)))
|
|
(setq win (next-window win 'not t))
|
|
(not (eq win top)))) ;; Loop while this is true.
|
|
(set-buffer orig-buffer)))))
|
|
|
|
;;}}}
|
|
|
|
;;}}}
|
|
;;{{{ Post Command Hook
|
|
|
|
;;; The magic little box. This function is called after every command.
|
|
|
|
;; This is not as complicated as it seems. It is simply a list of common
|
|
;; display situations and the actions to take, plus commands for redrawing
|
|
;; the screen if it should be unaligned.
|
|
;;
|
|
;; We divide the check into two parts; whether we are at the end or not.
|
|
;; This is due to the fact that the end can actaually be visible
|
|
;; in several window even though they are aligned.
|
|
|
|
(defun follow-post-command-hook ()
|
|
"Ensure that the windows in Follow mode are adjacent after each command."
|
|
(setq follow-inside-post-command-hook t)
|
|
(if (or (not (input-pending-p))
|
|
;; Sometimes, in XEmacs, mouse events are not handled
|
|
;; properly by `input-pending-p'. A typical example is
|
|
;; when clicking on a node in `info'.
|
|
(and (boundp 'current-mouse-event)
|
|
(symbol-value 'current-mouse-event)
|
|
(fboundp 'button-event-p)
|
|
(funcall (symbol-function 'button-event-p)
|
|
(symbol-value 'current-mouse-event))))
|
|
;; Work in the selected window, not in the current buffer.
|
|
(let ((orig-buffer (current-buffer))
|
|
(win (selected-window)))
|
|
(set-buffer (window-buffer win))
|
|
(or (and (symbolp this-command)
|
|
(get this-command 'follow-mode-use-cache))
|
|
(follow-invalidate-cache))
|
|
(if (and (boundp 'follow-mode) follow-mode
|
|
(not (window-minibuffer-p win)))
|
|
;; The buffer shown in the selected window is in follow
|
|
;; mode, lets find the current state of the display and
|
|
;; cache the result for speed (i.e. `aligned' and `visible'.)
|
|
(let* ((windows (inline (follow-all-followers win)))
|
|
(dest (point))
|
|
(win-start-end (inline
|
|
(follow-update-window-start (car windows))
|
|
(follow-windows-start-end windows)))
|
|
(aligned (follow-windows-aligned-p win-start-end))
|
|
(visible (follow-pos-visible dest win win-start-end)))
|
|
(if (not (and aligned visible))
|
|
(follow-invalidate-cache))
|
|
(inline (follow-avoid-tail-recenter))
|
|
;; Select a window to display the point.
|
|
(or follow-internal-force-redisplay
|
|
(progn
|
|
(if (eq dest (point-max))
|
|
;; We're at the end, we have be be careful since
|
|
;; the display can be aligned while `dest' can
|
|
;; be visible in several windows.
|
|
(cond
|
|
;; Select the current window, but only when
|
|
;; the display is correct. (When inserting
|
|
;; character in a tail window, the display is
|
|
;; not correct, as they are shown twice.)
|
|
;;
|
|
;; Never stick to the current window after a
|
|
;; deletion. The reason is cosmetic, when
|
|
;; typing `DEL' in a window showing only the
|
|
;; end of the file, character are removed
|
|
;; from the window above, which is very
|
|
;; unintuitive.
|
|
((and visible
|
|
aligned
|
|
(not (memq this-command
|
|
'(backward-delete-char
|
|
delete-backward-char
|
|
backward-delete-char-untabify
|
|
kill-region))))
|
|
(follow-debug-message "Max: same"))
|
|
;; If the end is visible, and the window
|
|
;; doesn't seems like it just has been moved,
|
|
;; select it.
|
|
((follow-select-if-end-visible win-start-end)
|
|
(follow-debug-message "Max: end visible")
|
|
(setq visible t)
|
|
(setq aligned nil)
|
|
(goto-char dest))
|
|
;; Just show the end...
|
|
(t
|
|
(follow-debug-message "Max: default")
|
|
(select-window (car (reverse windows)))
|
|
(goto-char dest)
|
|
(setq visible nil)
|
|
(setq aligned nil)))
|
|
|
|
;; We're not at the end, here life is much simpler.
|
|
(cond
|
|
;; This is the normal case!
|
|
;; It should be optimized for speed.
|
|
((and visible aligned)
|
|
(follow-debug-message "same"))
|
|
;; Pick a position in any window. If the
|
|
;; display is ok, this will pick the `correct'
|
|
;; window. If the display is wierd do this
|
|
;; anyway, this will be the case after a delete
|
|
;; at the beginning of the window.
|
|
((follow-select-if-visible dest win-start-end)
|
|
(follow-debug-message "visible")
|
|
(setq visible t)
|
|
(goto-char dest))
|
|
;; Not visible anywhere else, lets pick this one.
|
|
;; (Is this case used?)
|
|
(visible
|
|
(follow-debug-message "visible in selected."))
|
|
;; Far out!
|
|
((eq dest (point-min))
|
|
(follow-debug-message "min")
|
|
(select-window (car windows))
|
|
(goto-char dest)
|
|
(set-window-start (selected-window) (point-min))
|
|
(setq win-start-end (follow-windows-start-end windows))
|
|
(follow-invalidate-cache)
|
|
(setq visible t)
|
|
(setq aligned nil))
|
|
;; If we can position the cursor without moving the first
|
|
;; window, do it. This is the case that catches `RET'
|
|
;; at the bottom of a window.
|
|
((follow-select-if-visible-from-first dest windows)
|
|
(follow-debug-message "Below first")
|
|
(setq visible t)
|
|
(setq aligned t)
|
|
(follow-redisplay windows (car windows))
|
|
(goto-char dest))
|
|
;; None of the above. For simplicity, we stick to the
|
|
;; selected window.
|
|
(t
|
|
(follow-debug-message "None")
|
|
(setq visible nil)
|
|
(setq aligned nil))))
|
|
;; If a new window has been selected, make sure that the
|
|
;; old is not scrolled when the point is outside the
|
|
;; window.
|
|
(or (eq win (selected-window))
|
|
(let ((p (window-point win)))
|
|
(set-window-start win (window-start win) nil)
|
|
(set-window-point win p)))))
|
|
;; Make sure the point is visible in the selected window.
|
|
;; (This could lead to a scroll.)
|
|
(if (or visible
|
|
(follow-pos-visible dest win win-start-end))
|
|
nil
|
|
(sit-for 0)
|
|
(follow-avoid-tail-recenter)
|
|
(setq win-start-end (follow-windows-start-end windows))
|
|
(follow-invalidate-cache)
|
|
(setq aligned nil))
|
|
;; Redraw the windows whenever needed.
|
|
(if (or follow-internal-force-redisplay
|
|
(not (or aligned
|
|
(follow-windows-aligned-p win-start-end)))
|
|
(not (inline (follow-point-visible-all-windows-p
|
|
win-start-end))))
|
|
(progn
|
|
(setq follow-internal-force-redisplay nil)
|
|
(follow-redisplay windows (selected-window))
|
|
(setq win-start-end (follow-windows-start-end windows))
|
|
(follow-invalidate-cache)
|
|
;; When the point ends up in another window. This
|
|
;; happends when dest is in the beginning of the
|
|
;; file and the selected window is not the first.
|
|
;; It can also, in rare situations happend when
|
|
;; long lines are used and there is a big
|
|
;; difference between the width of the windows.
|
|
;; (When scrolling one line in a wide window which
|
|
;; will cause a move larger that an entire small
|
|
;; window.)
|
|
(if (follow-pos-visible dest win win-start-end)
|
|
nil
|
|
(follow-select-if-visible dest win-start-end)
|
|
(goto-char dest))))
|
|
|
|
;; If the region is visible, make it look good when spanning
|
|
;; multiple windows.
|
|
(if (or (and (boundp 'mark-active) (symbol-value 'mark-active))
|
|
(and (fboundp 'region-active-p)
|
|
(funcall (symbol-function 'region-active-p))))
|
|
(follow-maximize-region
|
|
(selected-window) windows win-start-end))
|
|
|
|
(inline (follow-avoid-tail-recenter))
|
|
;; DEBUG
|
|
;;(if (not (follow-windows-aligned-p
|
|
;; (follow-windows-start-end windows)))
|
|
;; (message "follow-mode: windows still unaligend!"))
|
|
;; END OF DEBUG
|
|
) ; Matches (let*
|
|
;; Buffer not in follow mode:
|
|
;; We still must update the windows displaying the tail so that
|
|
;; Emacs won't recenter them.
|
|
(follow-avoid-tail-recenter))
|
|
(set-buffer orig-buffer)))
|
|
(setq follow-inside-post-command-hook nil))
|
|
|
|
;;}}}
|
|
;;{{{ The region
|
|
|
|
;; Tries to make the highlighted area representing the region look
|
|
;; good when spanning several windows.
|
|
;;
|
|
;; Not perfect, as the point can't be placed at window end, only at
|
|
;; end-1. This will highlight a little bit in windows above
|
|
;; the current.
|
|
|
|
(defun follow-maximize-region (win windows win-start-end)
|
|
"Make a highlighted region stretching multiple windows look good."
|
|
(let* ((all (follow-split-followers windows win))
|
|
(pred (car all))
|
|
(succ (cdr all))
|
|
data)
|
|
(while pred
|
|
(setq data (assq (car pred) win-start-end))
|
|
(set-window-point (car pred) (max (nth 1 data) (- (nth 2 data) 1)))
|
|
(setq pred (cdr pred)))
|
|
(while succ
|
|
(set-window-point (car succ) (nth 1 (assq (car succ) win-start-end)))
|
|
(setq succ (cdr succ)))))
|
|
|
|
;;}}}
|
|
;;{{{ Scroll bar
|
|
|
|
;;;; Scroll-bar support code.
|
|
|
|
;;; Why is it needed? Well, if the selected window is in follow mode,
|
|
;;; all its follower stick to it blindly. If one of them is scrolled,
|
|
;;; it immediately returns to the original position when the mouse is
|
|
;;; released. If the selected window is not a follower of the dragged
|
|
;;; window the windows will be unaligned.
|
|
|
|
;;; The advices doesn't get compiled. Aestetically, this might be a
|
|
;;; problem but in practical life it isn't.
|
|
|
|
;;; Discussion: Now when the other windows in the chain follow the
|
|
;;; dragged, should we really select it?
|
|
|
|
(cond ((fboundp 'scroll-bar-drag)
|
|
;;;
|
|
;;; Emacs style scrollbars.
|
|
;;;
|
|
|
|
;; Select the dragged window if it is a follower of the
|
|
;; selected window.
|
|
;;
|
|
;; Generate advices of the form:
|
|
;; (defadvice scroll-bar-drag (after follow-scroll-bar-drag activate)
|
|
;; "Adviced by `follow-mode'."
|
|
;; (follow-redraw-after-event (ad-get-arg 0)))
|
|
(let ((cmds '(scroll-bar-drag
|
|
scroll-bar-drag-1 ; Executed at every move.
|
|
scroll-bar-scroll-down
|
|
scroll-bar-scroll-up
|
|
scroll-bar-set-window-start)))
|
|
(while cmds
|
|
(eval
|
|
`(defadvice ,(intern (symbol-name (car cmds)))
|
|
(after
|
|
,(intern (concat "follow-" (symbol-name (car cmds))))
|
|
activate)
|
|
"Adviced by Follow Mode."
|
|
(follow-redraw-after-event (ad-get-arg 0))))
|
|
(setq cmds (cdr cmds))))
|
|
|
|
|
|
(defun follow-redraw-after-event (event)
|
|
"Adviced by Follow mode."
|
|
(condition-case nil
|
|
(let* ((orig-win (selected-window))
|
|
(win (nth 0 (funcall
|
|
(symbol-function 'event-start) event)))
|
|
(fmode (assq 'follow-mode
|
|
(buffer-local-variables
|
|
(window-buffer win)))))
|
|
(if (and fmode (cdr fmode))
|
|
;; The selected window is in follow-mode
|
|
(progn
|
|
;; Recenter around the dragged window.
|
|
(select-window win)
|
|
(follow-redisplay)
|
|
(select-window orig-win))))
|
|
(error nil))))
|
|
|
|
|
|
((fboundp 'scrollbar-vertical-drag)
|
|
;;;
|
|
;;; XEmacs style scrollbars.
|
|
;;;
|
|
|
|
;; Advice all scrollbar functions on the form:
|
|
;;
|
|
;; (defadvice scrollbar-line-down
|
|
;; (after follow-scrollbar-line-down activate)
|
|
;; (follow-xemacs-scrollbar-support (ad-get-arg 0)))
|
|
|
|
(let ((cmds '(scrollbar-line-down ; Window
|
|
scrollbar-line-up
|
|
scrollbar-page-down ; Object
|
|
scrollbar-page-up
|
|
scrollbar-to-bottom ; Window
|
|
scrollbar-to-top
|
|
scrollbar-vertical-drag ; Object
|
|
)))
|
|
|
|
(while cmds
|
|
(eval
|
|
`(defadvice ,(intern (symbol-name (car cmds)))
|
|
(after
|
|
,(intern (concat "follow-" (symbol-name (car cmds))))
|
|
activate)
|
|
"Adviced by `follow-mode'."
|
|
(follow-xemacs-scrollbar-support (ad-get-arg 0))))
|
|
(setq cmds (cdr cmds))))
|
|
|
|
|
|
(defun follow-xemacs-scrollbar-support (window)
|
|
"Redraw windows showing the same buffer as shown in WINDOW.
|
|
WINDOW is either the dragged window, or a cons containing the
|
|
window as its first element. This is called while the user drags
|
|
the scrollbar.
|
|
|
|
WINDOW can be an object or a window."
|
|
(condition-case nil
|
|
(progn
|
|
(if (consp window)
|
|
(setq window (car window)))
|
|
(let ((fmode (assq 'follow-mode
|
|
(buffer-local-variables
|
|
(window-buffer window))))
|
|
(orig-win (selected-window)))
|
|
(if (and fmode (cdr fmode))
|
|
(progn
|
|
;; Recenter around the dragged window.
|
|
(select-window window)
|
|
(follow-redisplay)
|
|
(select-window orig-win)))))
|
|
(error nil)))))
|
|
|
|
;;}}}
|
|
;;{{{ Process output
|
|
|
|
;;; The following sections installs a spy that listens to process
|
|
;;; output and tries to reposition the windows whose buffers are in
|
|
;;; Follow mode. We play safe as much as possible...
|
|
;;;
|
|
;;; When follow-mode is activated all active processes are
|
|
;;; intercepted. All new processes that change their filter function
|
|
;;; using `set-process-filter' are also intercepted. The reason is
|
|
;;; that a process can cause a redisplay recentering "tail" windows.
|
|
;;; Note that it doesn't hurt to spy on more processes than needed.
|
|
;;;
|
|
;;; Technically, we set the process filter to `follow-generic-filter'.
|
|
;;; The original filter is stored in `follow-process-filter-alist'.
|
|
;;; Our generic filter calls the original filter, or inserts the
|
|
;;; output into the buffer, if the buffer originally didn't have an
|
|
;;; output filter. It also makes sure that the windows connected to
|
|
;;; the buffer are aligned.
|
|
;;;
|
|
;;; Discussion: How do we find processes that don't call
|
|
;;; `set-process-filter'? (How often are processes created in a
|
|
;;; buffer after Follow mode are activated?)
|
|
;;;
|
|
;;; Discussion: Should we also advice `process-filter' to make our
|
|
;;; filter invisible to others?
|
|
|
|
;;{{{ Advice for `set-process-filter'
|
|
|
|
;; Do not call this with 'follow-generic-filter as the name of the
|
|
;; filter...
|
|
|
|
(defadvice set-process-filter (before follow-set-process-filter activate)
|
|
"Ensure process output will be displayed correctly in Follow Mode buffers.
|
|
|
|
Follow Mode inserts its own process filter to do its
|
|
magic stuff before the real process filter is called."
|
|
(if follow-intercept-processes
|
|
(progn
|
|
(setq follow-process-filter-alist
|
|
(delq (assq (ad-get-arg 0) follow-process-filter-alist)
|
|
follow-process-filter-alist))
|
|
(follow-tidy-process-filter-alist)
|
|
(cond ((eq (ad-get-arg 1) t))
|
|
((eq (ad-get-arg 1) nil)
|
|
(ad-set-arg 1 'follow-generic-filter))
|
|
(t
|
|
(setq follow-process-filter-alist
|
|
(cons (cons (ad-get-arg 0) (ad-get-arg 1))
|
|
follow-process-filter-alist))
|
|
(ad-set-arg 1 'follow-generic-filter))))))
|
|
|
|
|
|
(defun follow-call-set-process-filter (proc filter)
|
|
"Call original `set-process-filter' without the Follow mode advice."
|
|
(ad-disable-advice 'set-process-filter 'before
|
|
'follow-set-process-filter)
|
|
(ad-activate 'set-process-filter)
|
|
(prog1
|
|
(set-process-filter proc filter)
|
|
(ad-enable-advice 'set-process-filter 'before
|
|
'follow-set-process-filter)
|
|
(ad-activate 'set-process-filter)))
|
|
|
|
|
|
(defadvice process-filter (after follow-process-filter activate)
|
|
"Return the original process filter, not `follow-generic-filter'."
|
|
(cond ((eq ad-return-value 'follow-generic-filter)
|
|
(setq ad-return-value
|
|
(cdr-safe (assq (ad-get-arg 0)
|
|
follow-process-filter-alist))))))
|
|
|
|
|
|
(defun follow-call-process-filter (proc)
|
|
"Call original `process-filter' without the Follow mode advice."
|
|
(ad-disable-advice 'process-filter 'after
|
|
'follow-process-filter)
|
|
(ad-activate 'process-filter)
|
|
(prog1
|
|
(process-filter proc)
|
|
(ad-enable-advice 'process-filter 'after
|
|
'follow-process-filter)
|
|
(ad-activate 'process-filter)))
|
|
|
|
|
|
(defun follow-tidy-process-filter-alist ()
|
|
"Remove old processes from `follow-process-filter-alist'."
|
|
(let ((alist follow-process-filter-alist)
|
|
(ps (process-list))
|
|
(new ()))
|
|
(while alist
|
|
(if (and (not (memq (process-status (car (car alist)))
|
|
'(exit signal closed nil)))
|
|
(memq (car (car alist)) ps))
|
|
(setq new (cons (car alist) new)))
|
|
(setq alist (cdr alist)))
|
|
(setq follow-process-filter-alist new)))
|
|
|
|
;;}}}
|
|
;;{{{ Start/stop interception of processes.
|
|
|
|
;; Normally, all new processed are intercepted by our `set-process-filter'.
|
|
;; This is needed to intercept old processed that were started before we were
|
|
;; loaded, and processes we have forgotten by calling
|
|
;; `follow-stop-intercept-process-output'.
|
|
|
|
(defun follow-intercept-process-output ()
|
|
"Intercept all active processes.
|
|
|
|
This is needed so that Follow Mode can track all display events in the
|
|
system. (See `follow-mode')"
|
|
(interactive)
|
|
(let ((list (process-list)))
|
|
(while list
|
|
(if (eq (process-filter (car list)) 'follow-generic-filter)
|
|
nil
|
|
;; The custom `set-process-filter' defined above.
|
|
(set-process-filter (car list) (process-filter (car list))))
|
|
(setq list (cdr list))))
|
|
(setq follow-intercept-processes t))
|
|
|
|
|
|
(defun follow-stop-intercept-process-output ()
|
|
"Stop Follow Mode from spying on processes.
|
|
|
|
All current spypoints are removed and no new will be added.
|
|
|
|
The effect is that Follow mode won't be able to handle buffers
|
|
connected to processes.
|
|
|
|
The only reason to call this function is if the Follow mode spy filter
|
|
would interfere with some other package. If this happens, please
|
|
report this using the `follow-submit-feedback' function."
|
|
(interactive)
|
|
(follow-tidy-process-filter-alist)
|
|
(let ((list (process-list)))
|
|
(while list
|
|
(if (eq (process-filter (car list)) 'follow-generic-filter)
|
|
(progn
|
|
(follow-call-set-process-filter
|
|
(car list)
|
|
(cdr-safe (assq (car list) follow-process-filter-alist)))
|
|
(setq follow-process-filter-alist
|
|
(delq (assq (car list) follow-process-filter-alist)
|
|
follow-process-filter-alist))))
|
|
(setq list (cdr list))))
|
|
(setq follow-intercept-processes nil))
|
|
|
|
;;}}}
|
|
;;{{{ The filter
|
|
|
|
;;; The following section is a naive method to make buffers with
|
|
;;; process output to work with Follow mode. Whenever the start of the
|
|
;;; window displaying the buffer is moved, we moves it back to its
|
|
;;; original position and try to select a new window. (If we fail,
|
|
;;; the normal redisplay functions of Emacs will scroll it right
|
|
;;; back!)
|
|
|
|
(defun follow-generic-filter (proc output)
|
|
"Process output filter for process connected to buffers in Follow mode."
|
|
(let* ((old-buffer (current-buffer))
|
|
(orig-win (selected-window))
|
|
(buf (process-buffer proc))
|
|
(win (and buf (if (eq buf (window-buffer orig-win))
|
|
orig-win
|
|
(get-buffer-window buf t))))
|
|
(return-to-orig-win (and win (not (eq win orig-win))))
|
|
(orig-window-start (and win (window-start win))))
|
|
|
|
;; If input is pending, the `sit-for' below won't redraw the
|
|
;; display. In that case, calling `follow-avoid-tail-recenter' may
|
|
;; provoke the process hadnling code to sceduling a redisplay.
|
|
;(or (input-pending-p)
|
|
; (follow-avoid-tail-recenter))
|
|
|
|
;; Output the `output'.
|
|
(let ((filter (cdr-safe (assq proc follow-process-filter-alist))))
|
|
(cond
|
|
;; Call the original filter function
|
|
(filter
|
|
(funcall filter proc output))
|
|
|
|
;; No filter, but we've got a buffer. Just output into it.
|
|
(buf
|
|
(set-buffer buf)
|
|
(if (not (marker-buffer (process-mark proc)))
|
|
(set-marker (process-mark proc) (point-max)))
|
|
(let ((moving (= (point) (process-mark proc)))
|
|
(odeactivate (and (boundp 'deactivate-mark)
|
|
(symbol-value 'deactivate-mark)))
|
|
(old-buffer-read-only buffer-read-only))
|
|
(setq buffer-read-only nil)
|
|
(save-excursion
|
|
(goto-char (process-mark proc))
|
|
;; `insert-before-markers' just in case the users next
|
|
;; command is M-y.
|
|
(insert-before-markers output)
|
|
(set-marker (process-mark proc) (point)))
|
|
(if moving (goto-char (process-mark proc)))
|
|
(if (boundp 'deactivate-mark)
|
|
;; This could really be
|
|
;; (setq deactivate-mark odeactivate)
|
|
;; but this raises an error when compiling on XEmacs.
|
|
(funcall (symbol-function 'set)
|
|
'deactivate-mark odeactivate))
|
|
(setq buffer-read-only old-buffer-read-only)))))
|
|
|
|
;; If we're in follow mode, do our stuff. Select a new window and
|
|
;; redisplay. (Actually, it is redundant to check `buf', but I
|
|
;; feel it's more correct.)
|
|
(if (and buf win (window-live-p win))
|
|
(progn
|
|
(set-buffer buf)
|
|
(if (and (boundp 'follow-mode) follow-mode)
|
|
(progn
|
|
(select-window win)
|
|
(let* ((windows (follow-all-followers win))
|
|
(win-start-end (follow-windows-start-end windows))
|
|
(new-window-start (window-start win))
|
|
(new-window-point (window-point win)))
|
|
(cond
|
|
;; The window was moved. Move it back and
|
|
;; select a new. If no better could be found,
|
|
;; we stick the the new start position. This
|
|
;; is used when the original process filter
|
|
;; tries to position the cursor at the bottom
|
|
;; of the window. Example: `lyskom'.
|
|
((not (eq orig-window-start new-window-start))
|
|
(follow-debug-message "filter: Moved")
|
|
(set-window-start win orig-window-start)
|
|
(follow-redisplay windows win)
|
|
(setq win-start-end (follow-windows-start-end windows))
|
|
(follow-select-if-visible new-window-point
|
|
win-start-end)
|
|
(goto-char new-window-point)
|
|
(if (eq win (selected-window))
|
|
(set-window-start win new-window-start))
|
|
(setq win-start-end (follow-windows-start-end windows)))
|
|
;; Stick to this window, if point is visible in it.
|
|
((pos-visible-in-window-p new-window-point)
|
|
(follow-debug-message "filter: Visible in window"))
|
|
;; Avoid redisplaying the first window. If the
|
|
;; point is visible at a window below,
|
|
;; redisplay and select it.
|
|
((follow-select-if-visible-from-first
|
|
new-window-point windows)
|
|
(follow-debug-message "filter: Seen from first")
|
|
(follow-redisplay windows (car windows))
|
|
(goto-char new-window-point)
|
|
(setq win-start-end
|
|
(follow-windows-start-end windows)))
|
|
;; None of the above. We stick to the current window.
|
|
(t
|
|
(follow-debug-message "filter: nothing")))
|
|
|
|
;; Here we have slected a window. Make sure the
|
|
;; windows are aligned and the point is visible
|
|
;; in the selected window.
|
|
(if (and (not (follow-pos-visible
|
|
(point) (selected-window) win-start-end))
|
|
(not return-to-orig-win))
|
|
(progn
|
|
(sit-for 0)
|
|
(setq win-start-end
|
|
(follow-windows-start-end windows))))
|
|
|
|
(if (or follow-internal-force-redisplay
|
|
(not (follow-windows-aligned-p win-start-end)))
|
|
(follow-redisplay windows)))))))
|
|
|
|
;; return to the original window.
|
|
(if return-to-orig-win
|
|
(select-window orig-win))
|
|
;; Restore the orignal buffer, unless the filter explicitly
|
|
;; changed buffer or killed the old buffer.
|
|
(if (and (eq buf (current-buffer))
|
|
(buffer-name old-buffer))
|
|
(set-buffer old-buffer)))
|
|
|
|
(follow-invalidate-cache)
|
|
|
|
;; Normally, if the display has been changed, it is redrawn. All
|
|
;; windows showing only the end of a buffer is unconditionally
|
|
;; recentered, we can't prevent it by calling
|
|
;; `follow-avoid-tail-recenter'.
|
|
;;
|
|
;; By performing a redisplay on our own, Emacs need not perform
|
|
;; the above described redisplay. (However, bu performing it when
|
|
;; there are input available just seems to make things worse.)
|
|
(if (and follow-avoid-tail-recenter-p
|
|
(not (input-pending-p)))
|
|
(sit-for 0)))
|
|
|
|
;;}}}
|
|
|
|
;;}}}
|
|
;;{{{ Window size change
|
|
|
|
;; In Emacs 19.29, the functions in `window-size-change-functions' are
|
|
;; called every time a window in a frame changes size. Most notably, it
|
|
;; is called after the frame has been resized.
|
|
;;
|
|
;; We basically call our post-command-hook for every buffer that is
|
|
;; visible in any window in the resized frame, which is in follow-mode.
|
|
;;
|
|
;; Since this function can be called indirectly from
|
|
;; `follow-post-command-hook' we have a potential infinite loop. We
|
|
;; handle this problem by simply not doing anything at all in this
|
|
;; situation. The variable `follow-inside-post-command-hook' contains
|
|
;; information about whether the execution actually is inside the
|
|
;; post-command-hook or not.
|
|
|
|
(if (boundp 'window-size-change-functions)
|
|
(add-hook 'window-size-change-functions 'follow-window-size-change))
|
|
|
|
|
|
(defun follow-window-size-change (frame)
|
|
"Redraw all windows in FRAME, when in Follow mode."
|
|
;; Below, we call `post-command-hook'. This makes sure that we
|
|
;; doesn't start a mutally recursive endless loop.
|
|
(if follow-inside-post-command-hook
|
|
nil
|
|
(let ((buffers '())
|
|
(orig-window (selected-window))
|
|
(orig-buffer (current-buffer))
|
|
(orig-frame (selected-frame))
|
|
windows
|
|
buf)
|
|
(select-frame frame)
|
|
(unwind-protect
|
|
(walk-windows
|
|
(function
|
|
(lambda (win)
|
|
(setq buf (window-buffer win))
|
|
(if (memq buf buffers)
|
|
nil
|
|
(set-buffer buf)
|
|
(if (and (boundp 'follow-mode)
|
|
follow-mode)
|
|
(progn
|
|
(setq windows (follow-all-followers win))
|
|
(if (memq orig-window windows)
|
|
(progn
|
|
;; Make sure we're redrawing around the
|
|
;; selected window.
|
|
;;
|
|
;; We must be really careful not to do this
|
|
;; when we are (indirectly) called by
|
|
;; `post-command-hook'.
|
|
(select-window orig-window)
|
|
(follow-post-command-hook)
|
|
(setq orig-window (selected-window)))
|
|
(follow-redisplay windows win))
|
|
(setq buffers (cons buf buffers))))))))
|
|
(select-frame orig-frame)
|
|
(set-buffer orig-buffer)
|
|
(select-window orig-window)))))
|
|
|
|
;;}}}
|
|
|
|
;;{{{ XEmacs isearch
|
|
|
|
;; In XEmacs, isearch often finds matches in other windows than the
|
|
;; currently selected. However, when exiting the old window
|
|
;; configuration is restored, with the exception of the beginning of
|
|
;; the start of the window for the selected window. This is not much
|
|
;; help for us.
|
|
;;
|
|
;; We overwrite the stored window configuration with the current,
|
|
;; unless we are in `slow-search-mode', i.e. only a few lines
|
|
;; of text is visible.
|
|
|
|
(if follow-emacs-version-xemacs-p
|
|
(defadvice isearch-done (before follow-isearch-done activate)
|
|
(if (and (boundp 'follow-mode)
|
|
follow-mode
|
|
(boundp 'isearch-window-configuration)
|
|
isearch-window-configuration
|
|
(boundp 'isearch-slow-terminal-mode)
|
|
(not isearch-slow-terminal-mode))
|
|
(let ((buf (current-buffer)))
|
|
(setq isearch-window-configuration
|
|
(current-window-configuration))
|
|
(set-buffer buf)))))
|
|
|
|
;;}}}
|
|
;;{{{ Tail window handling
|
|
|
|
;;; In Emacs (not XEmacs) windows showing nothing are sometimes
|
|
;;; recentered. When in Follow Mode, this is not desireable for
|
|
;;; non-first windows in the window chain. This section tries to
|
|
;;; make the windows stay where they should be.
|
|
;;;
|
|
;;; If the display is updated, all windows starting at (point-max) are
|
|
;;; going to be recentered at the next redisplay, unless we do a
|
|
;;; read-and-write cycle to update the `force' flag inside the windows.
|
|
;;;
|
|
;;; In 19.30, a new varible `window-scroll-functions' is called every
|
|
;;; time a window is recentered. It is not perfect for our situation,
|
|
;;; since when it is called for a tail window, it is to late. However,
|
|
;;; if it is called for another window, we can try to update our
|
|
;;; windows.
|
|
;;;
|
|
;;; By patching `sit-for' we can make sure that to catch all explicit
|
|
;;; updates initiated by lisp programs. Internal calls, on the other
|
|
;;; hand, are not handled.
|
|
;;;
|
|
;;; Please note that the function `follow-avoid-tail-recenter' is also
|
|
;;; called from other places, e.g. `post-command-hook' and
|
|
;;; `post-command-idle-hook'.
|
|
|
|
;; If this function is called it is too late for this window, but
|
|
;; we might save other windows from being recentered.
|
|
|
|
(if (and follow-avoid-tail-recenter-p (boundp 'window-scroll-functions))
|
|
(add-hook 'window-scroll-functions 'follow-avoid-tail-recenter t))
|
|
|
|
|
|
;; This prevents all packages that calls `sit-for' directly
|
|
;; to recenter tail windows.
|
|
|
|
(if follow-avoid-tail-recenter-p
|
|
(defadvice sit-for (before follow-sit-for activate)
|
|
"Adviced by Follow Mode.
|
|
|
|
Avoid to recenter windows displaying only the end of a file as when
|
|
displaying a short file in two windows, using Follow Mode."
|
|
(follow-avoid-tail-recenter)))
|
|
|
|
|
|
;; Without this advice, `mouse-drag-region' would start to recenter
|
|
;; tail windows.
|
|
|
|
(if (and follow-avoid-tail-recenter-p
|
|
(fboundp 'move-overlay))
|
|
(defadvice move-overlay (before follow-move-overlay activate)
|
|
"Adviced by Follow Mode.
|
|
Don't recenter windows showing only the end of a buffer.
|
|
This prevents `mouse-drag-region' from messing things up."
|
|
(follow-avoid-tail-recenter)))
|
|
|
|
;;}}}
|
|
;;{{{ profile support
|
|
|
|
;; The following (non-evaluated) section can be used to
|
|
;; profile this package using `elp'.
|
|
;;
|
|
;; Invalid indentation on purpose!
|
|
|
|
(cond (nil
|
|
(setq elp-function-list
|
|
'(window-end
|
|
vertical-motion
|
|
; sit-for ;; elp can't handle advices...
|
|
follow-mode
|
|
follow-all-followers
|
|
follow-split-followers
|
|
follow-redisplay
|
|
follow-downward
|
|
follow-calculate-first-window-start
|
|
follow-estimate-first-window-start
|
|
follow-calculate-first-window-start-from-above
|
|
follow-calculate-first-window-start-from-below
|
|
follow-calc-win-end
|
|
follow-calc-win-start
|
|
follow-pos-visible
|
|
follow-windows-start-end
|
|
follow-cache-valid-p
|
|
follow-select-if-visible
|
|
follow-select-if-visible-from-first
|
|
follow-windows-aligned-p
|
|
follow-point-visible-all-windows-p
|
|
follow-avoid-tail-recenter
|
|
follow-update-window-start
|
|
follow-post-command-hook
|
|
))))
|
|
|
|
;;}}}
|
|
|
|
;;{{{ The end
|
|
|
|
;;;
|
|
;;; We're done!
|
|
;;;
|
|
|
|
(provide 'follow)
|
|
|
|
;;}}}
|
|
|
|
;; /------------------------------------------------------------------------\
|
|
;; | "I [..] am rarely happier then when spending an entire day programming |
|
|
;; | my computer to perform automatically a task that it would otherwise |
|
|
;; | take me a good ten seconds to do by hand. Ten seconds, I tell myself, |
|
|
;; | is ten seconds. Time is valuable and ten seconds' worth of it is well |
|
|
;; | worth the investment of a day's happy activity working out a way to |
|
|
;; | save it". -- Douglas Adams, "Last Chance to See" |
|
|
;; \------------------------------------------------------------------------/
|
|
|
|
;;; follow.el ends here
|