lisp/mh-e/mh-buffers.el

   1 ;;; mh-buffers.el --- MH-E buffer constants and utilities
   2
   3 ;; Copyright (C) 1993, 1995, 1997, 2000-2017 Free Software Foundation,
   4 ;; Inc.
   5
   6 ;; Author: Bill Wohler <wohler@newt.com>
   7 ;; Maintainer: Bill Wohler <wohler@newt.com>
   8 ;; Keywords: mail
   9 ;; See: mh-e.el
  10
  11 ;; This file is part of GNU Emacs.
  12
  13 ;; GNU Emacs is free software: you can redistribute it and/or modify
  14 ;; it under the terms of the GNU General Public License as published by
  15 ;; the Free Software Foundation, either version 3 of the License, or
  16 ;; (at your option) any later version.
  17
  18 ;; GNU Emacs is distributed in the hope that it will be useful,
  19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21 ;; GNU General Public License for more details.
  22
  23 ;; You should have received a copy of the GNU General Public License
  24 ;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
  25
  26 ;;; Commentary:
  27
  28 ;;; Change Log:
  29
  30 ;;; Code:
  31
  32 ;; The names of ephemeral buffers have a " *mh-" prefix (so that they
  33 ;; are hidden and can be programmatically removed in mh-quit), and the
  34 ;; variable names have the form mh-temp-.*-buffer.
  35 (defconst mh-temp-buffer " *mh-temp*")  ;scratch
  36 (defconst mh-temp-checksum-buffer " *mh-checksum*")
  37 (defconst mh-temp-fetch-buffer " *mh-fetch*")  ;wget/curl/fetch output
  38 (defconst mh-temp-index-buffer " *mh-index*")
  39
  40 ;; The names of MH-E buffers that are not ephemeral and can be used by
  41 ;; the user (and deleted by the user when no longer needed) have a
  42 ;; "*MH-E " prefix (so they can be programmatically removed in
  43 ;; mh-quit), and the variable names have the form mh-.*-buffer.
  44 ;; Temporary buffers for search results
  45 (defconst mh-aliases-buffer "*MH-E Aliases*") ;alias lookups
  46 (defconst mh-folders-buffer "*MH-E Folders*") ;folder list
  47 (defconst mh-help-buffer "*MH-E Help*") ;quick help
  48 (defconst mh-info-buffer "*MH-E Info*") ;version information buffer
  49 (defconst mh-log-buffer "*MH-E Log*") ;output of MH commands and so on
  50 (defconst mh-mail-delivery-buffer "*MH-E Mail Delivery*") ;mail delivery log
  51 (defconst mh-recipients-buffer "*MH-E Recipients*") ;killed when draft sent
  52 (defconst mh-sequences-buffer "*MH-E Sequences*") ;sequences list
  53
  54 (defvar mh-log-buffer-lines 100
  55   "Number of lines to keep in `mh-log-buffer'.")
  56
  57 \f
  58
  59 (defun mh-truncate-log-buffer ()
  60   "If `mh-log-buffer' is too big then truncate it.
  61 If the number of lines in `mh-log-buffer' exceeds
  62 `mh-log-buffer-lines' then keep only the last
  63 `mh-log-buffer-lines'. As a side effect the point is set to the
  64 end of the log buffer.
  65
  66 The function returns the size of the final size of the log buffer."
  67   (with-current-buffer (get-buffer-create mh-log-buffer)
  68     (goto-char (point-max))
  69     (save-excursion
  70       (when (equal (forward-line (- mh-log-buffer-lines)) 0)
  71         (delete-region (point-min) (point))))
  72     (unless (or (bobp)
  73                 (save-excursion
  74                   (and (equal (forward-line -1) 0) (equal (char-after) ?\f))))
  75       (insert "\n\f\n"))
  76     (buffer-size)))
  77
  78 (provide 'mh-buffers)
  79
  80 ;; Local Variables:
  81 ;; indent-tabs-mode: nil
  82 ;; sentence-end-double-space: nil
  83 ;; End:
  84
  85 ;;; mh-buffers.el ends here