branch: externals/autorevert-tail-truncate
commit 662a27f883c01648a099f5859e166ee8f24021fa
Author: shipmints <shipmi...@gmail.com>
Commit: shipmints <shipmi...@gmail.com>
Actual initial commit
---
.elpaignore | 1 +
.gitignore | 7 ++
README.md | 76 ++++++++++++++-
autorevert-tail-truncate.el | 219 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 302 insertions(+), 1 deletion(-)
diff --git a/.elpaignore b/.elpaignore
new file mode 100644
index 0000000000..6b1d0bfabc
--- /dev/null
+++ b/.elpaignore
@@ -0,0 +1 @@
+LICENSE
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000000..9d48fea457
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,7 @@
+*-autoloads.el
+*-pkg.el
+*.elc
+*.info
+*.texi
+*~
+\#*\#
diff --git a/README.md b/README.md
index d46d87459d..233a484df8 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,76 @@
+<!-- -*- mode: gfm; coding: utf-8; tab-width: 2; fill-column: 130; eval:
(visual-line-mode t) -*- -->
+
# autorevert-tail-truncate.el
-Extend Emacs extends auto-revert-tail-mode to optimize memory and cpu
+
+Extend Emacs auto-revert-tail-mode to optimize memory and CPU.
+
+`auto-revert-tail-truncate-mode` extends `auto-revert-tail-mode` to automate
truncating the tailed buffer to a
+user-specified number of lines. This allows you, for example, to tail log
files in an auto-reverting buffer forever without
+running out of memory. By default, a newly tailed buffer is immediately
truncated for the same reason. Also, by default, the
+buffer's undo log is disabled along with font-lock to both preserve memory and
optimize CPU consumption.
+
+Use the command `auto-revert-tail-truncate-file` to open a file in a new
buffer with `auto-revert-tail-truncate-mode`
+enabled.
+
+Add a function (example, below) to `auto-revert-tail-truncate-mode-hook` to
control additional features in your tailed buffers;
+e.g., `truncate-lines`, controlling `so-long-mode` threshold, disabling spell
checking, or enabling other minor modes for
+specific log-file formats (the visual features of which may require you to
enable font-lock for those buffers).
+
+If you want this mode enabled for all *.log files, run the command
+`auto-revert-tail-mode-on-log-files` or add this to your `init.el` file.
+
+Refer to the source code or docstrings for details on user options.
+
+## Installation
+
+`autorevert-tail-truncate.el` is not yet part of Emacs (it will be submitted
for consideration to be included in Emacs 31) and has not yet been published on
ELPA.
+
+If you use Emacs 29.1+, use `package-vc-install`. In your `*scratch*` buffer,
copy/paste or type the following, and run it via
+the command `eval-last-sexp`, which see:
+
+``` elisp
+(package-vc-install '(autorevert-tail-truncate :url
"https://github.com/shipmints/autorevert-tail-truncate.el";))
+```
+
+Or, if you use Emacs 30+, uncomment the :vc stanza, below.
+
+``` elisp
+(use-package autorevert-tail-truncate
+ ;; :vc (
+ ;; :url "https://github.com/shipmints/autorevert-tail-truncate.el";
+ ;; :branch "master")
+ :config
+ (setq auto-revert-tail-truncate-max-lines 5000) ; default 5000
+ (setq auto-revert-tail-truncate-file-size-hint 64) ; default 64
+ (setq auto-revert-tail-truncate-immediately t) ; default t
+ (setq auto-revert-tail-truncate-verbose nil) ; default nil
+ (setq auto-revert-tail-truncate-immediately t) ; default t
+ (setq auto-revert-tail-truncate-read-only t) ; deault t
+ (setq auto-revert-tail-truncate-disable-undo t) ; default t
+ (setq auto-revert-tail-truncate-disable-font-lock t) ; default t
+
+ (defun my/auto-revert-tail-truncate-mode-hook ()
+ "Custom `auto-revert-tail-truncate-mode' hook."
+ (setq-local auto-revert-tail-truncate-max-lines 10000)
+ (setq-local truncate-lines t)
+ (when (fboundp 'so-long-mode)
+ (setq-local so-long-threshold 25000))
+ (when (eq my:spell-checker 'jinx)
+ (jinx-mode -1))
+ (when (fboundp 'show-smartparens-mode)
+ (show-smartparens-mode -1)))
+ (add-hook 'auto-revert-tail-truncate-mode-hook
#'my/auto-revert-tail-truncate-mode-hook)
+ ;; add auto-mode-alist entry for .log files to use auto-revert-tail-mode
+ (auto-revert-tail-mode-on-log-files))
+```
+
+## Coda
+
+I put this into the package because the earliest Emacs I can easily support is
29.x. This will likely be altered if the package is
+published in ELPA and most certainly will be removed as a part of Emacs 31, if
accepted.
+
+ ;; Package-Requires: ((emacs "29.1"))
+
+This is a new package, and though the author successfully uses it, your
mileage may vary. The author does not used specialized
+log-file modes such as https://github.com/doublep/logview or
https://github.com/emacsmirror/log4j-mode -- if you do, and find
+issues that you cannot resolve via your configuration, file an issue here.
diff --git a/autorevert-tail-truncate.el b/autorevert-tail-truncate.el
new file mode 100644
index 0000000000..9104143628
--- /dev/null
+++ b/autorevert-tail-truncate.el
@@ -0,0 +1,219 @@
+;;; autorevert-tail-truncate.el -- Summary;: -*- mode: emacs-lisp;
lexical-binding: t; -*-
+
+;; Copyright (C) 2025 Stephane Marks
+;; Copyright (C) 2025 Free Software Foundation, Inc.
+
+;; Author: Stephane Marks <shipmi...@gmail.com>
+;; Maintainer: Stephane Marks <shipmi...@gmail.com>
+;; Url: https://github.com/shipmints/autorevert-tail-truncate.el
+;; Created: 2025-02-03
+;; Version: 1.0
+;; Package-Requires: ((emacs "29.1"))
+;; Keywords: convenience, tools, log files, autorevert
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+;;
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;; GNU General Public License for more details.
+;;
+;; You should have received a copy of the GNU General Public License
+;; along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; `auto-revert-tail-truncate-mode' extends `auto-revert-tail-mode' to
+;; automate truncating the tailed buffer to a user-specified number of
+;; lines. This allows you, for example, to tail log files in an
+;; auto-reverting buffer forever without running out of memory. By
+;; default, a newly tailed buffer is immediately truncated for the
+;; same reason. Also, by default, the buffer's undo log is disabled
+;; along with font-lock to both preserve memory and optimize CPU
+;; consumption.
+;;
+;; Use the command auto-revert-tail-truncate-file to open a file in a
+;; new buffer with `auto-revert-tail-truncate-mode' enabled.
+;;
+;; Add a function to `auto-revert-tail-truncate-mode-hook' to control
+;; additional features in your tailed buffers; e.g., truncate-lines,
+;; controlling so-long-mode threshold, disabling spell checking, or
+;; enabling other minor modes for specific log-file formats (the
+;; visual features of which may require you to enable font-lock for
+;; those buffers).
+;;
+;; If you want this mode enabled for all *.log files, run the command
+;; `auto-revert-tail-mode-on-log-files'.
+
+;;; Code:
+
+(require 'autorevert)
+
+(defcustom auto-revert-tail-truncate-max-lines 5000
+ "Truncate buffer to this maximum number of lines.
+If nil, truncation is disabled. Bind this as a buffer-local variable to
+control the maximum number lines to retain for specific buffers."
+ :group 'auto-revert
+ :type 'natnum
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-file-size-hint 64
+ "Bytes per line hint to `auto-revert-tail-truncate-file'.
+This is multiplied by `auto-revert-tail-truncate-max-lines' to compute
+the initial bytes to load."
+ :group 'auto-revert
+ :type 'natnum
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-revert-interval auto-revert-interval
+ "Number of seconds between Auto-Revert Tail Truncate Mode file checks.
+The default value is `auto-revert-interval', which see."
+ :group 'auto-revert
+ :type 'natnum
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-verbose auto-revert-verbose
+ "When nil, `auto-revert-tail-truncate-mode' does not generate messages.
+When non-nil, a message is generated whenever a buffer is reverted.
+The default value is `auto-revert-verbose', which see."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-immediately t
+ "If non-nil, buffer is truncated when this mode is enabled.
+Set the maximum number of lines to retain in the buffer using the
+option `auto-revert-tail-truncate-max-lines', which see."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-read-only t
+ "If non-nil, the tailed buffer is set to be read only."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-disable-undo t
+ "If non-nil, the buffer's undo log is disabled to save memory."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-disable-font-lock t
+ "If non-nil, font-lock is disabled on the tailed buffer."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-check-vc-info auto-revert-check-vc-info
+ "If non-nil `auto-revert-tail-truncate-mode' updates vc info.
+The default value is `auto-revert-check-vc-info', which see."
+ :group 'auto-revert
+ :type 'boolean
+ :version "31.1")
+
+(defcustom auto-revert-tail-truncate-mode-text " TailTrunc"
+ "Mode line string when `auto-revert-tail-truncate-mode' is active."
+ :group 'auto-revert
+ :type 'string
+ :version "31.1")
+
+(defvar-local auto-revert-tail-truncate-mode nil
+ "Non-nil when `auto-revert-tail-truncate-mode' is active.
+Never set this variable directly, use the command
+`auto-revert-tail-truncate-mode' instead.")
+(put 'auto-revert-tail-truncate-mode 'permanent-local t)
+
+;;;###autoload
+(define-minor-mode auto-revert-tail-truncate-mode
+ "`auto-revert-tail-mode' with automatic buffer line truncation.
+Truncation does not affect the content of underlying file, only the
+buffer in which it is displayed.
+
+Customize `auto-revert-tail-mode-hook' to control features such as
+`truncate-lines' for the tailed buffer."
+ :group 'find-file
+ :lighter auto-revert-tail-truncate-mode-text
+ (if auto-revert-tail-truncate-mode
+ (progn
+ (setq-local auto-revert-tail-mode-text nil) ; this mode's lighter has
priority
+ (auto-revert-tail-mode)
+ (make-local-variable 'auto-revert-interval)
+ (make-local-variable 'auto-revert-timer)
+ (setopt auto-revert-interval auto-revert-tail-truncate-revert-interval)
+ (setq-local auto-revert-verbose auto-revert-tail-truncate-verbose)
+ (when auto-revert-tail-truncate-read-only
+ (read-only-mode))
+ (when auto-revert-tail-truncate-disable-undo
+ (buffer-disable-undo))
+ (when auto-revert-tail-truncate-disable-font-lock
+ (font-lock-mode -1))
+ (make-local-variable 'auto-revert-check-vc-info)
+ (setq auto-revert-check-vc-info
auto-revert-tail-truncate-check-vc-info)
+ (goto-char (point-max))
+ (when auto-revert-tail-truncate-immediately
+ (auto-revert--tail-truncate))
+ (add-hook 'after-revert-hook #'auto-revert--tail-truncate nil 'local))
+ (remove-hook 'after-revert-hook #'auto-revert--tail-truncate 'local)
+ (auto-revert-tail-mode -1)))
+
+(defun turn-on-auto-revert-tail-truncate-mode ()
+ "Turn on `auto-revert-tail-truncate-mode'.
+
+This function is designed to be added to hooks, for example:
+\(add-hook \\='my-logfile-mode-hook
#\\='turn-on-auto-revert-tail-truncate-mode)"
+ (auto-revert-tail-truncate-mode 1))
+
+(defun auto-revert--tail-truncate ()
+ "Called via buffer local `after-revert-hook' to truncate the buffer."
+ (when auto-revert-tail-truncate-max-lines
+ (with-silent-modifications
+ (save-restriction
+ (widen)
+ (save-excursion
+ (goto-char (point-max))
+ (forward-line (- auto-revert-tail-truncate-max-lines))
+ (beginning-of-line)
+ (let ((inhibit-read-only t))
+ (delete-region (point-min) (point))))))))
+
+;;;###autoload
+(defun auto-revert-tail-truncate-file (filename)
+ "Prompt for a file to tail using `auto-revert-tail-truncate-mode'.
+Invoke programmatically specifying FILENAME."
+ (interactive "fFile to auto revert tail (with truncate): ")
+ (let* ((filename (abbreviate-file-name (expand-file-name filename)))
+ (max-size (* auto-revert-tail-truncate-max-lines
+ auto-revert-tail-truncate-file-size-hint))
+ (size (file-attribute-size (file-attributes filename)))
+ (beg (if (< size max-size) 0 (- size max-size)))
+ (end size)
+ (existing-buf (get-file-buffer filename))
+ (buf))
+ (when existing-buf
+ (when (y-or-n-p "Use and truncate the existing buffer (\"no\" makes a
new buffer)?")
+ (setq buf existing-buf)))
+ (unless buf
+ (setq buf (create-file-buffer filename))
+ (with-current-buffer buf
+ (with-silent-modifications
+ (insert-file-contents filename nil beg end)
+ (set-visited-file-name filename nil t)
+ (set-buffer-modified-p nil)))) ; also silences auto-revert-tail-mode
"Buffer is modified..." warning
+ (with-current-buffer buf
+ (auto-revert-tail-truncate-mode))
+ (pop-to-buffer buf)))
+
+;;;###autoload
+(defun auto-revert-tail-mode-on-log-files ()
+ "Enable `auto-revert-tail-truncate-mode' for all *.log files."
+ (interactive)
+ (add-to-list 'auto-mode-alist '("\\.log\\'" .
auto-revert-tail-truncate-mode)))
+
+(provide 'autorevert-tail-truncate)
+
+;;; autorevert-tail-truncate.el ends here
