lisp/erc/erc-log.el

   1 ;;; erc-log.el --- Logging facilities for ERC.
   2
   3 ;; Copyright (C) 2003-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Lawrence Mitchell <wence@gmx.li>
   6 ;; Maintainer: FSF
   7 ;; Keywords: IRC, chat, client, Internet, logging
   8
   9 ;; Created 2003-04-26
  10 ;; Logging code taken from erc.el and modified to use markers.
  11
  12 ;; This file is part of GNU Emacs.
  13
  14 ;; GNU Emacs is free software: you can redistribute it and/or modify
  15 ;; it under the terms of the GNU General Public License as published by
  16 ;; the Free Software Foundation, either version 3 of the License, or
  17 ;; (at your option) any later version.
  18
  19 ;; GNU Emacs is distributed in the hope that it will be useful,
  20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 ;; GNU General Public License for more details.
  23
  24 ;; You should have received a copy of the GNU General Public License
  25 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  26
  27 ;;; Commentary:
  28
  29 ;; This file implements log file writing support for ERC.
  30
  31 ;; Quick start:
  32 ;;
  33 ;; (require 'erc-log)
  34 ;; (setq erc-log-channels-directory "/path/to/logfiles") ; must be writable
  35 ;; (erc-log-enable)
  36 ;;
  37 ;; Or:
  38 ;;
  39 ;; M-x customize-variable erc-modules, and add "log".
  40 ;;
  41 ;; There are two ways to setup logging.  The first (default) method
  42 ;; will save buffers on /part, /quit, or killing the channel
  43 ;; buffer.
  44 ;;
  45 ;; The second will write to the log files on each incoming or outgoing
  46 ;; line - this may not be optimal on a laptop HDD.  To use this
  47 ;; method, add the following to the above instructions.
  48 ;;
  49 ;; (setq erc-save-buffer-on-part nil
  50 ;;       erc-save-queries-on-quit nil
  51 ;;       erc-log-write-after-send t
  52 ;;       erc-log-write-after-insert t)
  53 ;;
  54 ;; If you only want to save logs for some buffers, customize the
  55 ;; variable `erc-enable-logging'.
  56
  57 ;; How it works:
  58 ;;
  59 ;; If logging is enabled, at some point, `erc-save-buffer-in-logs'
  60 ;; will be called.  The "end" of the buffer is taken from
  61 ;; `erc-insert-marker', while `erc-last-saved-position' holds the
  62 ;; position the buffer was last saved at (as a marker, or if the
  63 ;; buffer hasn't been saved before, as the number 1 (point-min)).
  64
  65 ;; The region between `erc-last-saved-position' and
  66 ;; `erc-insert-marker' is saved to the current buffer's logfile, and
  67 ;; `erc-last-saved-position' is updated to reflect this.
  68
  69 ;;; History:
  70 ;; 2003-04-26: logging code pulled out of erc.el.  Switched to using
  71 ;; markers.
  72
  73 ;;; TODO:
  74 ;;
  75 ;; * Really, we need to lock the logfiles somehow, so that if a user
  76 ;;   is running multiple emacsen and/or on the same channel as more
  77 ;;   than one user, only one process writes to the logfile.  This is
  78 ;;   especially needed for those logfiles with no nick in them, as
  79 ;;   these would become corrupted.
  80 ;;   For a single emacs process, the problem could be solved using a
  81 ;;   variable which contained the names of buffers already being
  82 ;;   logged.  This would require that logging be buffer-local,
  83 ;;   possibly not a bad thing anyway, since many people don't want to
  84 ;;   log the server buffer.
  85 ;;   For multiple emacsen the problem is trickier.  On some systems,
  86 ;;   on could use the function `lock-buffer' and `unlock-buffer'.
  87 ;;   However, file locking isn't implemented on all platforms, for
  88 ;;   example, there is none on w32 systems.
  89 ;;   A third possibility might be to fake lockfiles.  However, this
  90 ;;   might lead to problems if an emacs crashes, as the lockfile
  91 ;;   would be left lying around.
  92
  93 ;;; Code:
  94
  95 (require 'erc)
  96 (eval-when-compile (require 'erc-networks))
  97
  98 (defgroup erc-log nil
  99   "Logging facilities for ERC."
 100   :group 'erc)
 101
 102 (defcustom erc-generate-log-file-name-function 'erc-generate-log-file-name-long
 103   "A function to generate a log filename.
 104 The function must take five arguments: BUFFER, TARGET, NICK, SERVER and PORT.
 105 BUFFER is the buffer to be saved,
 106 TARGET is the name of the channel, or the target of the query,
 107 NICK is the current nick,
 108 SERVER and PORT are the parameters that were used to connect to BUFFERs
 109 `erc-server-process'.
 110
 111 If you want to write logs into different directories, make a
 112 custom function which returns the directory part and set
 113 `erc-log-channels-directory' to its name."
 114   :group 'erc-log
 115   :type '(choice (const :tag "#channel!nick@server:port.txt"
 116                         erc-generate-log-file-name-long)
 117                  (const :tag "#channel!nick@network.txt"
 118                         erc-generate-log-file-name-network)
 119                  (const :tag "#channel.txt" erc-generate-log-file-name-short)
 120                  (const :tag "#channel@date.txt"
 121                         erc-generate-log-file-name-with-date)
 122                  (function :tag "Other function")))
 123
 124 (defcustom erc-truncate-buffer-on-save nil
 125   "Truncate any ERC (channel, query, server) buffer when it is saved."
 126   :group 'erc-log
 127   :type 'boolean)
 128
 129 (defcustom erc-enable-logging t
 130   "If non-nil, ERC will log IRC conversations.
 131 This can either be a boolean value of nil or t, or a function.
 132 If the value is a function, it will be called with one argument, the
 133 name of the current ERC buffer.  One possible function, which saves
 134 all but server buffers is `erc-log-all-but-server-buffers'.
 135
 136 This variable is buffer local.  Setting it via \\[customize] sets the
 137 default value.
 138
 139 Log files are stored in `erc-log-channels-directory'."
 140   :group 'erc-log
 141   :type '(choice boolean
 142                  function))
 143 (make-variable-buffer-local 'erc-enable-logging)
 144
 145 (defcustom erc-log-channels-directory "~/log"
 146   "The directory to place log files for channels.
 147 Leave blank to disable logging.  If not nil, all the channel
 148 buffers are logged in separate files in that directory.  The
 149 directory should not end with a trailing slash.
 150
 151 If this is the name of a function, the function will be called
 152 with the buffer, target, nick, server, and port arguments.  See
 153 `erc-generate-log-file-name-function' for a description of these
 154 arguments."
 155   :group 'erc-log
 156   :type '(choice directory
 157                  (function "Function")
 158                  (const :tag "Disable logging" nil)))
 159
 160 (defcustom erc-log-insert-log-on-open nil
 161   "Insert log file contents into the buffer if a log file exists."
 162   :group 'erc-log
 163   :type 'boolean)
 164
 165 (defcustom erc-save-buffer-on-part t
 166   "Save the channel buffer content using `erc-save-buffer-in-logs' on PART.
 167
 168 If you set this to nil, you may want to enable both
 169 `erc-log-write-after-send' and `erc-log-write-after-insert'."
 170   :group 'erc-log
 171   :type 'boolean)
 172
 173 (defcustom erc-save-queries-on-quit t
 174   "Save all query (also channel) buffers of the server on QUIT.
 175
 176 If you set this to nil, you may want to enable both
 177 `erc-log-write-after-send' and `erc-log-write-after-insert'."
 178   :group 'erc-log
 179   :type 'boolean)
 180
 181 (defcustom erc-log-write-after-send nil
 182   "If non-nil, write to log file after every message you send.
 183
 184 If you set this to nil, you may want to enable both
 185 `erc-save-buffer-on-part' and `erc-save-queries-on-quit'."
 186   :group 'erc-log
 187   :type 'boolean)
 188
 189 (defcustom erc-log-write-after-insert nil
 190   "If non-nil, write to log file when new text is added to a
 191 logged ERC buffer.
 192
 193 If you set this to nil, you may want to enable both
 194 `erc-save-buffer-on-part' and `erc-save-queries-on-quit'."
 195   :group 'erc-log
 196   :type 'boolean)
 197
 198 (defcustom erc-log-file-coding-system (if (featurep 'xemacs)
 199                                           'binary
 200                                         'emacs-mule)
 201   "The coding system ERC should use for writing log files.
 202
 203 This should ideally, be a \"catch-all\" coding system, like
 204 `emacs-mule', or `iso-2022-7bit'."
 205   :type 'coding-system
 206   :group 'erc-log)
 207
 208 (defcustom erc-log-filter-function nil
 209   "If non-nil, pass text through the given function before writing it to
 210 a log file.
 211
 212 The function should take one argument, which is the text to filter."
 213   :group 'erc-log
 214   :type '(choice (function "Function")
 215                  (const :tag "No filtering" nil)))
 216
 217
 218 ;;;###autoload (autoload 'erc-log-mode "erc-log" nil t)
 219 (define-erc-module log nil
 220   "Automatically logs things you receive on IRC into files.
 221 Files are stored in `erc-log-channels-directory'; file name
 222 format is defined through a formatting function on
 223 `erc-generate-log-file-name-function'.
 224
 225 Since automatic logging is not always a Good Thing (especially if
 226 people say things in different coding systems), you can turn logging
 227 behavior on and off with the variable `erc-enable-logging', which can
 228 also be a predicate function.  To only log when you are not set away, use:
 229
 230 \(setq erc-enable-logging
 231       (lambda (buffer)
 232         (with-current-buffer buffer
 233           (null (erc-away-time)))))"
 234   ;; enable
 235   ((when erc-log-write-after-insert
 236      (add-hook 'erc-insert-post-hook 'erc-save-buffer-in-logs))
 237    (when erc-log-write-after-send
 238      (add-hook 'erc-send-post-hook 'erc-save-buffer-in-logs))
 239    (add-hook 'erc-kill-buffer-hook 'erc-save-buffer-in-logs)
 240    (add-hook 'erc-kill-channel-hook 'erc-save-buffer-in-logs)
 241    (add-hook 'kill-emacs-hook 'erc-log-save-all-buffers)
 242    (add-hook 'erc-quit-hook 'erc-conditional-save-queries)
 243    (add-hook 'erc-part-hook 'erc-conditional-save-buffer)
 244    ;; append, so that 'erc-initialize-log-marker runs first
 245    (add-hook 'erc-connect-pre-hook 'erc-log-setup-logging 'append)
 246    (dolist (buffer (erc-buffer-list))
 247      (erc-log-setup-logging buffer)))
 248   ;; disable
 249   ((remove-hook 'erc-insert-post-hook 'erc-save-buffer-in-logs)
 250    (remove-hook 'erc-send-post-hook 'erc-save-buffer-in-logs)
 251    (remove-hook 'erc-kill-buffer-hook 'erc-save-buffer-in-logs)
 252    (remove-hook 'erc-kill-channel-hook 'erc-save-buffer-in-logs)
 253    (remove-hook 'kill-emacs-hook 'erc-log-save-all-buffers)
 254    (remove-hook 'erc-quit-hook 'erc-conditional-save-queries)
 255    (remove-hook 'erc-part-hook 'erc-conditional-save-buffer)
 256    (remove-hook 'erc-connect-pre-hook 'erc-log-setup-logging)
 257    (dolist (buffer (erc-buffer-list))
 258      (erc-log-disable-logging buffer))))
 259
 260 (define-key erc-mode-map "\C-c\C-l" 'erc-save-buffer-in-logs)
 261
 262 ;;; functionality referenced from erc.el
 263 (defun erc-log-setup-logging (buffer)
 264   "Setup the buffer-local logging variables in the current buffer.
 265 This function is destined to be run from `erc-connect-pre-hook'.
 266 The current buffer is given by BUFFER."
 267   (when (erc-logging-enabled buffer)
 268     (with-current-buffer buffer
 269       (auto-save-mode -1)
 270       (setq buffer-file-name nil)
 271       (erc-set-write-file-functions '(erc-save-buffer-in-logs))
 272       (when erc-log-insert-log-on-open
 273         (ignore-errors (insert-file-contents (erc-current-logfile))
 274                        (move-marker erc-last-saved-position
 275                                     (1- (point-max))))))))
 276
 277 (defun erc-log-disable-logging (buffer)
 278   "Disable logging in BUFFER."
 279   (when (erc-logging-enabled buffer)
 280     (with-current-buffer buffer
 281       (setq buffer-offer-save nil
 282             erc-enable-logging nil))))
 283
 284 (defun erc-log-all-but-server-buffers (buffer)
 285   "Returns t if logging should be enabled in BUFFER.
 286 Returns nil if `erc-server-buffer-p' returns t."
 287   (save-excursion
 288     (save-window-excursion
 289       (set-buffer buffer)
 290       (not (erc-server-buffer-p)))))
 291
 292 (defun erc-save-query-buffers (process)
 293   "Save all buffers of the given PROCESS."
 294   (erc-with-all-buffers-of-server process
 295                                   nil
 296                                   (erc-save-buffer-in-logs)))
 297
 298 (defun erc-conditional-save-buffer (buffer)
 299   "Save Query BUFFER if `erc-save-queries-on-quit' is t."
 300   (when erc-save-buffer-on-part
 301     (erc-save-buffer-in-logs buffer)))
 302
 303 (defun erc-conditional-save-queries (process)
 304   "Save Query buffers of PROCESS if `erc-save-queries-on-quit' is t."
 305   (when erc-save-queries-on-quit
 306     (erc-save-query-buffers process)))
 307
 308 ;; Make sure that logs get saved, even if someone overrides the active
 309 ;; process prompt for a quick exit from Emacs
 310 (defun erc-log-save-all-buffers ()
 311   (dolist (buffer (erc-buffer-list))
 312     (erc-save-buffer-in-logs buffer)))
 313
 314 ;;;###autoload
 315 (defun erc-logging-enabled (&optional buffer)
 316   "Return non-nil if logging is enabled for BUFFER.
 317 If BUFFER is nil, the value of `current-buffer' is used.
 318 Logging is enabled if `erc-log-channels-directory' is non-nil, the directory
 319 is writable (it will be created as necessary) and
 320 `erc-enable-logging' returns a non-nil value."
 321   (and erc-log-channels-directory
 322        (or (functionp erc-log-channels-directory)
 323            (erc-directory-writable-p erc-log-channels-directory))
 324        (if (functionp erc-enable-logging)
 325            (funcall erc-enable-logging (or buffer (current-buffer)))
 326          erc-enable-logging)))
 327
 328 (defun erc-log-standardize-name (filename)
 329   "Make FILENAME safe to use as the name of an ERC log.
 330 This will not work with full paths, only names.
 331
 332 Any unsafe characters in the name are replaced with \"!\".  The
 333 filename is downcased."
 334   (downcase (erc-replace-regexp-in-string
 335              "[/\\]" "!" (convert-standard-filename filename))))
 336
 337 (defun erc-current-logfile (&optional buffer)
 338   "Return the logfile to use for BUFFER.
 339 If BUFFER is nil, the value of `current-buffer' is used.
 340 This is determined by `erc-generate-log-file-name-function'.
 341 The result is converted to lowercase, as IRC is case-insensitive"
 342   (unless buffer (setq buffer (current-buffer)))
 343   (let ((target (or (buffer-name buffer) (erc-default-target)))
 344         (nick (erc-current-nick))
 345         (server erc-session-server)
 346         (port erc-session-port))
 347     (expand-file-name
 348      (erc-log-standardize-name
 349       (funcall erc-generate-log-file-name-function
 350                buffer target nick server port))
 351      (if (functionp erc-log-channels-directory)
 352          (funcall erc-log-channels-directory
 353                   buffer target nick server port)
 354        erc-log-channels-directory))))
 355
 356 (defun erc-generate-log-file-name-with-date (buffer &rest ignore)
 357   "This function computes a short log file name.
 358 The name of the log file is composed of BUFFER and the current date.
 359 This function is a possible value for `erc-generate-log-file-name-function'."
 360   (concat (buffer-name buffer) "-" (format-time-string "%Y-%m-%d") ".txt"))
 361
 362 (defun erc-generate-log-file-name-short (buffer &rest ignore)
 363   "This function computes a short log file name.
 364 In fact, it only uses the buffer name of the BUFFER argument, so
 365 you can affect that using `rename-buffer' and the-like.  This
 366 function is a possible value for
 367 `erc-generate-log-file-name-function'."
 368   (concat (buffer-name buffer) ".txt"))
 369
 370 (defun erc-generate-log-file-name-long (buffer target nick server port)
 371   "Generates a log-file name in the way ERC always did it.
 372 This results in a file name of the form #channel!nick@server:port.txt.
 373 This function is a possible value for `erc-generate-log-file-name-function'."
 374   (let ((file (concat
 375                (if target (concat target "!"))
 376                nick "@" server ":" (cond ((stringp port) port)
 377                                          ((numberp port)
 378                                           (number-to-string port))) ".txt")))
 379     ;; we need a make-safe-file-name function.
 380     (convert-standard-filename file)))
 381
 382 (declare-function erc-network-name "erc-networks" ())
 383
 384 (defun erc-generate-log-file-name-network (buffer target nick server port)
 385   "Generates a log-file name using the network name rather than server name.
 386 This results in a file name of the form #channel!nick@network.txt.
 387 This function is a possible value for `erc-generate-log-file-name-function'."
 388   (require 'erc-networks)
 389   (let ((file (concat
 390                (if target (concat target "!"))
 391                nick "@"
 392                (or (with-current-buffer buffer (erc-network-name)) server)
 393                ".txt")))
 394     ;; we need a make-safe-file-name function.
 395     (convert-standard-filename file)))
 396
 397 ;;;###autoload
 398 (defun erc-save-buffer-in-logs (&optional buffer)
 399   "Append BUFFER contents to the log file, if logging is enabled.
 400 If BUFFER is not provided, current buffer is used.
 401 Logging is enabled if `erc-logging-enabled' returns non-nil.
 402
 403 This is normally done on exit, to save the unsaved portion of the
 404 buffer, since only the text that runs off the buffer limit is logged
 405 automatically.
 406
 407 You can save every individual message by putting this function on
 408 `erc-insert-post-hook'."
 409   (interactive)
 410   (or buffer (setq buffer (current-buffer)))
 411   (when (erc-logging-enabled buffer)
 412     (let ((file (erc-current-logfile buffer))
 413           (coding-system erc-log-file-coding-system)
 414           (inhibit-clash-detection t))  ; needed for XEmacs
 415       (save-excursion
 416         (with-current-buffer buffer
 417           (save-restriction
 418             (widen)
 419             ;; early on in the initialization, don't try and write the log out
 420             (when (and (markerp erc-last-saved-position)
 421                        (> erc-insert-marker (1+ erc-last-saved-position)))
 422               (let ((start (1+ (marker-position erc-last-saved-position)))
 423                     (end (marker-position erc-insert-marker)))
 424                 (if (functionp erc-log-filter-function)
 425                     (let ((text (buffer-substring start end)))
 426                       (with-temp-buffer
 427                         (insert (funcall erc-log-filter-function text))
 428                         (let ((coding-system-for-write coding-system))
 429                           (write-region (point-min) (point-max)
 430                                         file t 'nomessage))))
 431                   (let ((coding-system-for-write coding-system))
 432                     (write-region start end file t 'nomessage))))
 433               (if (and erc-truncate-buffer-on-save
 434                        (called-interactively-p 'interactive))
 435                   (progn
 436                     (let ((inhibit-read-only t)) (erase-buffer))
 437                     (move-marker erc-last-saved-position (point-max))
 438                     (erc-display-prompt))
 439                 (move-marker erc-last-saved-position
 440                              ;; If we place erc-last-saved-position at
 441                              ;; erc-insert-marker, because text gets
 442                              ;; inserted /before/ erc-insert-marker,
 443                              ;; the log file will not be saved
 444                              ;; (erc-last-saved-position will always
 445                              ;; be equal to erc-insert-marker).
 446                              (1- (marker-position erc-insert-marker)))))
 447             (set-buffer-modified-p nil))))))
 448   t)
 449
 450 (provide 'erc-log)
 451
 452 ;;; erc-log.el ends here
 453 ;;
 454 ;; Local Variables:
 455 ;; indent-tabs-mode: t
 456 ;; tab-width: 8
 457 ;; End: