code.delx.au - gnu-emacs/blob - lisp/gnus/gnus-ems.el

   1 ;;; gnus-ems.el --- functions for making Gnus work under different Emacsen
   2
   3 ;; Copyright (C) 1995-2016 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;; Keywords: news
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;;; Code:
  26
  27 (eval-when-compile
  28   (require 'cl)
  29   (require 'ring))
  30
  31 ;;; Function aliases later to be redefined for XEmacs usage.
  32
  33 (defvar gnus-mouse-2 [mouse-2])
  34 (defvar gnus-down-mouse-3 [down-mouse-3])
  35 (defvar gnus-down-mouse-2 [down-mouse-2])
  36 (defvar gnus-widget-button-keymap nil)
  37 (defvar gnus-mode-line-modified
  38   (if (featurep 'xemacs)
  39       '("--**-" . "-----")
  40     '("**" "--")))
  41
  42 (eval-and-compile
  43   (autoload 'gnus-xmas-define "gnus-xmas")
  44   (autoload 'gnus-xmas-redefine "gnus-xmas"))
  45
  46 (autoload 'gnus-get-buffer-create "gnus")
  47 (autoload 'nnheader-find-etc-directory "nnheader")
  48 (autoload 'smiley-region "smiley")
  49
  50 (defun gnus-kill-all-overlays ()
  51   "Delete all overlays in the current buffer."
  52   (let* ((overlayss (overlay-lists))
  53          (buffer-read-only nil)
  54          (overlays (delq nil (nconc (car overlayss) (cdr overlayss)))))
  55     (while overlays
  56       (delete-overlay (pop overlays)))))
  57
  58 ;;; Mule functions.
  59
  60 (defun gnus-mule-max-width-function (el max-width)
  61   `(let* ((val (eval (, el)))
  62           (valstr (if (numberp val)
  63                       (int-to-string val) val)))
  64      (if (> (length valstr) ,max-width)
  65          (truncate-string-to-width valstr ,max-width)
  66        valstr)))
  67
  68 (eval-and-compile
  69   (if (featurep 'xemacs)
  70       (gnus-xmas-define)
  71     (defvar gnus-mouse-face-prop 'mouse-face
  72       "Property used for highlighting mouse regions.")))
  73
  74 (defvar gnus-tmp-unread)
  75 (defvar gnus-tmp-replied)
  76 (defvar gnus-tmp-score-char)
  77 (defvar gnus-tmp-indentation)
  78 (defvar gnus-tmp-opening-bracket)
  79 (defvar gnus-tmp-lines)
  80 (defvar gnus-tmp-name)
  81 (defvar gnus-tmp-closing-bracket)
  82 (defvar gnus-tmp-subject-or-nil)
  83 (defvar gnus-check-before-posting)
  84 (defvar gnus-mouse-face)
  85 (defvar gnus-group-buffer)
  86
  87 (defun gnus-ems-redefine ()
  88   (cond
  89    ((featurep 'xemacs)
  90     (gnus-xmas-redefine))
  91
  92    ((featurep 'mule)
  93     ;; Mule and new Emacs definitions
  94
  95     ;; [Note] Now there are three kinds of mule implementations,
  96     ;; original MULE, XEmacs/mule and Emacs 20+ including
  97     ;; MULE features.  Unfortunately these APIs are different.  In
  98     ;; particular, Emacs (including original Mule) and XEmacs are
  99     ;; quite different.  However, this version of Gnus doesn't support
 100     ;; anything other than XEmacs 20+ and Emacs 20.3+.
 101
 102     ;; Predicates to check are following:
 103     ;; (boundp 'MULE) is t only if Mule (original; anything older than
 104     ;;                     Mule 2.3) is running.
 105     ;; (featurep 'mule) is t when other mule variants are running.
 106
 107     ;; It is possible to detect XEmacs/mule by (featurep 'mule) and
 108     ;; (featurep 'xemacs).  In this case, the implementation for
 109     ;; XEmacs/mule may be shareable between XEmacs and XEmacs/mule.
 110
 111     (defvar gnus-summary-display-table nil
 112       "Display table used in summary mode buffers.")
 113     (defalias 'gnus-max-width-function 'gnus-mule-max-width-function)
 114
 115     (when (boundp 'gnus-check-before-posting)
 116       (setq gnus-check-before-posting
 117             (delq 'long-lines
 118                   (delq 'control-chars gnus-check-before-posting))))
 119
 120     (defun gnus-summary-line-format-spec ()
 121       (insert gnus-tmp-unread gnus-tmp-replied
 122               gnus-tmp-score-char gnus-tmp-indentation)
 123       (put-text-property
 124        (point)
 125        (progn
 126          (insert
 127           gnus-tmp-opening-bracket
 128           (format "%4d: %-20s"
 129                   gnus-tmp-lines
 130                   (if (> (length gnus-tmp-name) 20)
 131                       (truncate-string-to-width gnus-tmp-name 20)
 132                     gnus-tmp-name))
 133           gnus-tmp-closing-bracket)
 134          (point))
 135        gnus-mouse-face-prop gnus-mouse-face)
 136       (insert " " gnus-tmp-subject-or-nil "\n")))))
 137
 138 ;; Clone of `appt-select-lowest-window' in appt.el.
 139 (defun gnus-select-lowest-window ()
 140 "Select the lowest window on the frame."
 141   (let ((lowest-window (selected-window))
 142         (bottom-edge (nth 3 (window-edges))))
 143     (walk-windows (lambda (w)
 144                     (let ((next-bottom-edge (nth 3 (window-edges w))))
 145                       (when (< bottom-edge next-bottom-edge)
 146                         (setq bottom-edge next-bottom-edge
 147                               lowest-window w)))))
 148     (select-window lowest-window)))
 149
 150 (defun gnus-region-active-p ()
 151   "Say whether the region is active."
 152   (and (boundp 'transient-mark-mode)
 153        transient-mark-mode
 154        (boundp 'mark-active)
 155        mark-active))
 156
 157 (defun gnus-mark-active-p ()
 158   "Non-nil means the mark and region are currently active in this buffer."
 159   mark-active) ; aliased to region-exists-p in XEmacs.
 160
 161 (autoload 'gnus-alive-p "gnus-util")
 162 (autoload 'mm-disable-multibyte "mm-util")
 163
 164 ;;; Image functions.
 165
 166 (defun gnus-image-type-available-p (type)
 167   (and (fboundp 'image-type-available-p)
 168        (if (fboundp 'display-images-p)
 169            (display-images-p)
 170          t)
 171        (image-type-available-p type)))
 172
 173 (defun gnus-create-image (file &optional type data-p &rest props)
 174   (let ((face (plist-get props :face)))
 175     (when face
 176       (setq props (plist-put props :foreground (face-foreground face)))
 177       (setq props (plist-put props :background (face-background face))))
 178     (ignore-errors
 179       (apply 'create-image file type data-p props))))
 180
 181 (defun gnus-put-image (glyph &optional string category)
 182   (let ((point (point)))
 183     (insert-image glyph (or string " "))
 184     (put-text-property point (point) 'gnus-image-category category)
 185     (unless string
 186       (put-text-property (1- (point)) (point)
 187                          'gnus-image-text-deletable t))
 188     glyph))
 189
 190 (defun gnus-remove-image (image &optional category)
 191   "Remove the image matching IMAGE and CATEGORY found first."
 192   (let ((start (point-min))
 193         val end)
 194     (while (and (not end)
 195                 (or (setq val (get-text-property start 'display))
 196                     (and (setq start
 197                                (next-single-property-change start 'display))
 198                          (setq val (get-text-property start 'display)))))
 199       (setq end (or (next-single-property-change start 'display)
 200                     (point-max)))
 201       (if (and (equal val image)
 202                (equal (get-text-property start 'gnus-image-category)
 203                       category))
 204           (progn
 205             (put-text-property start end 'display nil)
 206             (when (get-text-property start 'gnus-image-text-deletable)
 207               (delete-region start end)))
 208         (unless (= end (point-max))
 209           (setq start end
 210                 end nil))))))
 211
 212 (provide 'gnus-ems)
 213
 214 ;;; gnus-ems.el ends here