1;;; mail-hist.el --- headers and message body history for outgoing mail 2 3;; Copyright (C) 1994, 2001, 2002, 2003, 2004, 2005, 4;; 2006, 2007 Free Software Foundation, Inc. 5 6;; Author: Karl Fogel <kfogel@red-bean.com> 7;; Created: March, 1994 8;; Keywords: mail, history 9 10;; This file is part of GNU Emacs. 11 12;; GNU Emacs is free software; you can redistribute it and/or modify 13;; it under the terms of the GNU General Public License as published by 14;; the Free Software Foundation; either version 2, or (at your option) 15;; any later version. 16 17;; GNU Emacs is distributed in the hope that it will be useful, 18;; but WITHOUT ANY WARRANTY; without even the implied warranty of 19;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 20;; GNU General Public License for more details. 21 22;; You should have received a copy of the GNU General Public License 23;; along with GNU Emacs; see the file COPYING. If not, write to the 24;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 25;; Boston, MA 02110-1301, USA. 26 27;;; Commentary: 28 29;; Thanks to Jim Blandy for mentioning ring.el. It saved a lot of 30;; time. 31;; 32;; To use this package, put it in a directory in your load-path, and 33;; put this in your .emacs file: 34;; 35;; (load "mail-hist" nil t) 36;; 37;; Or you could do it with autoloads and hooks in your .emacs: 38;; 39;; (add-hook 'mail-mode-hook 'mail-hist-define-keys) 40;; (add-hook 'mail-send-hook 'mail-hist-put-headers-into-history) 41;; (add-hook 'vm-mail-mode-hook 'mail-hist-define-keys) ;or rmail, etc 42;; (autoload 'mail-hist-define-keys "mail-hist") 43;; (autoload 'mail-hist-put-headers-into-history "mail-hist") 44;; 45;; Once it's installed, use M-p and M-n from mail headers to recover 46;; previous/next contents in the history for that header, or, in the 47;; body of the message, to recover previous/next text of the message. 48;; This only applies to outgoing mail -- mail-hist ignores received 49;; messages. 50;; 51;; Although repeated history requests do clear out the text from the 52;; previous request, an isolated request just inserts its text at 53;; point, so that you can mix the histories of different messages 54;; easily. This might be confusing at times, but there should be no 55;; problems that undo can't handle. 56 57;;; Code: 58(require 'ring) 59(require 'sendmail) 60 61(defgroup mail-hist nil 62 "Headers and message body history for outgoing mail." 63 :prefix "mail-hist-" 64 :group 'mail) 65 66;;;###autoload 67(defun mail-hist-define-keys () 68 "Define keys for accessing mail header history. For use in hooks." 69 (local-set-key "\M-p" 'mail-hist-previous-input) 70 (local-set-key "\M-n" 'mail-hist-next-input)) 71 72;;;###autoload 73(defun mail-hist-enable () 74 (add-hook 'mail-mode-hook 'mail-hist-define-keys) 75 (add-hook 'mail-send-hook 'mail-hist-put-headers-into-history)) 76 77(defvar mail-hist-header-ring-alist nil 78 "Alist of form (header-name . history-ring). 79Used for knowing which history list to look in when the user asks for 80previous/next input.") 81 82(defcustom mail-hist-history-size (or kill-ring-max 1729) 83 "*The maximum number of elements in a mail field's history. 84Oldest elements are dumped first." 85 :type 'integer 86 :group 'mail-hist) 87 88;;;###autoload 89(defcustom mail-hist-keep-history t 90 "*Non-nil means keep a history for headers and text of outgoing mail." 91 :type 'boolean 92 :group 'mail-hist) 93 94;; For handling repeated history requests 95(defvar mail-hist-access-count 0) 96 97(defvar mail-hist-last-bounds nil) 98;; (start . end) A pair indicating the buffer positions delimiting the 99;; last inserted history, so it can be replaced by a new input if the 100;; command is repeated. 101 102(defvar mail-hist-header-regexp "^[^:]*:" 103 "Regular expression for matching headers in a mail message.") 104 105(defsubst mail-hist-current-header-name () 106 "Get name of mail header point is currently in, without the colon. 107Returns nil if not in a header, implying that point is in the body of 108the message." 109 (if (>= (point) (mail-text-start)) 110 nil ; then we are in the body of the message 111 (save-excursion 112 (let* ((body-start 113 (mail-text-start)) 114 (name-start 115 (re-search-backward mail-hist-header-regexp nil t)) 116 (name-end 117 (prog2 (search-forward ":" body-start t) (1- (point))))) 118 (and 119 name-start 120 name-end 121 (downcase (buffer-substring-no-properties name-start name-end))))))) 122 123(defsubst mail-hist-forward-header (count) 124 "Move forward COUNT headers (backward if COUNT is negative). 125If last/first header is encountered first, stop there and returns 126nil. 127 128Places point on the first non-whitespace on the line following the 129colon after the header name, or on the second space following that if 130the header is empty." 131 (let ((boundary (mail-header-end))) 132 (and 133 (> boundary 0) 134 (let ((unstopped t)) 135 (setq boundary (save-excursion 136 (goto-char boundary) 137 (beginning-of-line) 138 (1- (point)))) 139 (if (> count 0) 140 (while (> count 0) 141 (setq 142 unstopped 143 (re-search-forward mail-hist-header-regexp boundary t)) 144 (setq count (1- count))) 145 ;; because the current header will match too. 146 (setq count (1- count)) 147 ;; count is negative 148 (while (< count 0) 149 (setq 150 unstopped 151 (re-search-backward mail-hist-header-regexp nil t)) 152 (setq count (1+ count))) 153 ;; we end up behind the header, so must move to the front 154 (re-search-forward mail-hist-header-regexp boundary t)) 155 ;; Now we are right after the colon 156 (and (looking-at "\\s-") (forward-char 1)) 157 ;; return nil if didn't go as far as asked, otherwise point 158 unstopped)))) 159 160(defsubst mail-hist-beginning-of-header () 161 "Move to the start of the current header. 162The start of the current header is defined as one space after the 163colon, or just after the colon if it is not followed by whitespace." 164 ;; this is slick as all heck: 165 (if (mail-hist-forward-header -1) 166 (mail-hist-forward-header 1) 167 (mail-hist-forward-header 1) 168 (mail-hist-forward-header -1))) 169 170(defsubst mail-hist-current-header-contents () 171 "Get the contents of the mail header in which point is located." 172 (save-excursion 173 (mail-hist-beginning-of-header) 174 (let ((start (point))) 175 (or (mail-hist-forward-header 1) 176 (goto-char (mail-header-end))) 177 (beginning-of-line) 178 (buffer-substring start (1- (point)))))) 179 180(defsubst mail-hist-get-header-ring (header) 181 "Get HEADER's history ring, or nil if none. 182HEADER is a string without the colon." 183 (setq header (downcase header)) 184 (cdr (assoc header mail-hist-header-ring-alist))) 185 186(defcustom mail-hist-text-size-limit nil 187 "*Don't store any header or body with more than this many characters. 188If the value is nil, that means no limit on text size." 189 :type '(choice (const nil) integer) 190 :group 'mail-hist) 191 192(defun mail-hist-text-too-long-p (text) 193 "Return non-nil if TEXT's length exceeds `mail-hist-text-size-limit'." 194 (if mail-hist-text-size-limit 195 (> (length text) mail-hist-text-size-limit))) 196 197(defsubst mail-hist-add-header-contents-to-ring (header &optional contents) 198 "Add the contents of HEADER to the header history ring. 199Optional argument CONTENTS is a string which will be the contents 200\(instead of whatever's found in the header)." 201 (setq header (downcase header)) 202 (let ((ctnts (or contents (mail-hist-current-header-contents))) 203 (ring (cdr (assoc header mail-hist-header-ring-alist)))) 204 (if (mail-hist-text-too-long-p ctnts) (setq ctnts "")) 205 (or ring 206 ;; If the ring doesn't exist, we'll have to make it and add it 207 ;; to the mail-header-ring-alist: 208 (prog1 209 (setq ring (make-ring mail-hist-history-size)) 210 (setq mail-hist-header-ring-alist 211 (cons (cons header ring) mail-hist-header-ring-alist)))) 212 (ring-insert ring ctnts))) 213 214;;;###autoload 215(defun mail-hist-put-headers-into-history () 216 "Put headers and contents of this message into mail header history. 217Each header has its own independent history, as does the body of the 218message. 219 220This function normally would be called when the message is sent." 221 (and 222 mail-hist-keep-history 223 (save-excursion 224 (goto-char (point-min)) 225 (while (mail-hist-forward-header 1) 226 (mail-hist-add-header-contents-to-ring 227 (mail-hist-current-header-name))) 228 (let ((body-contents 229 (buffer-substring (mail-text-start) (point-max)))) 230 (mail-hist-add-header-contents-to-ring "body" body-contents))))) 231 232 233 234(defun mail-hist-retrieve-and-insert (header access-func) 235 "Helper for `mail-hist-previous-input' and `mail-hist-next-input'." 236 (setq header (downcase header)) 237 (let* ((ring (cdr (assoc header mail-hist-header-ring-alist))) 238 (len (ring-length ring)) 239 (repeat (eq last-command 'mail-hist-input-access))) 240 (if repeat 241 (setq mail-hist-access-count 242 (funcall access-func mail-hist-access-count len)) 243 (setq mail-hist-access-count 0)) 244 (if (null ring) 245 (progn 246 (ding) 247 (message "No history for \"%s\"." header)) 248 (if (ring-empty-p ring) 249 (error "\"%s\" ring is empty" header) 250 (and repeat 251 (delete-region (car mail-hist-last-bounds) 252 (cdr mail-hist-last-bounds))) 253 (let ((start (point))) 254 (insert (ring-ref ring mail-hist-access-count)) 255 (setq mail-hist-last-bounds (cons start (point))) 256 (setq this-command 'mail-hist-input-access) 257 ;; Special case: when flipping through message bodies, it's 258 ;; usually most useful for point to stay at the top. This 259 ;; is because the unique part of a message in a thread is 260 ;; more likely to be at the top than the bottom, as the 261 ;; bottom is often just the same quoted history for every 262 ;; message in the thread, differing only in indentation 263 ;; level. 264 (if (string-equal header "body") 265 (goto-char start))) 266 )))) 267 268 269(defun mail-hist-previous-input (header) 270 "Insert the previous contents of this mail header or message body. 271Moves back through the history of sent mail messages. Each header has 272its own independent history, as does the body of the message. 273 274The history only contains the contents of outgoing messages, not 275received mail." 276 (interactive (list (or (mail-hist-current-header-name) "body"))) 277 (mail-hist-retrieve-and-insert header 'ring-plus1)) 278 279 280(defun mail-hist-next-input (header) 281 "Insert next contents of this mail header or message body. 282Moves back through the history of sent mail messages. Each header has 283its own independent history, as does the body of the message. 284 285Although you can do so, it does not make much sense to call this 286without having called `mail-hist-previous-header' first 287\(\\[mail-hist-previous-header]). 288 289The history only contains the contents of outgoing messages, not 290received mail." 291 (interactive (list (or (mail-hist-current-header-name) "body"))) 292 (mail-hist-retrieve-and-insert header 'ring-minus1)) 293 294 295(provide 'mail-hist) 296 297;;; arch-tag: 9ff9a07c-9dca-482d-ba87-54f42778559d 298;;; mail-hist.el ends here 299