lisp/progmodes/cc-compat.el

   1 ;;; cc-compat.el --- cc-mode compatibility with c-mode.el confusion
   2
   3 ;; Copyright (C) 1985, 1987, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
   4 ;;   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
   5 ;;   Free Software Foundation, Inc.
   6
   7 ;; Authors:    1998- Martin Stjernholm
   8 ;;             1994-1999 Barry A. Warsaw
   9 ;; Maintainer: bug-cc-mode@gnu.org
  10 ;; Created:    August 1994, split from cc-mode.el
  11 ;; Version:    See cc-mode.el
  12 ;; Keywords:   c languages oop
  13
  14 ;; This file is part of GNU Emacs.
  15
  16 ;; GNU Emacs is free software; you can redistribute it and/or modify
  17 ;; it under the terms of the GNU General Public License as published by
  18 ;; the Free Software Foundation; either version 3, or (at your option)
  19 ;; any later version.
  20
  21 ;; GNU Emacs is distributed in the hope that it will be useful,
  22 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24 ;; GNU General Public License for more details.
  25
  26 ;; You should have received a copy of the GNU General Public License
  27 ;; along with this program; see the file COPYING.  If not, write to
  28 ;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  29 ;; Boston, MA 02110-1301, USA.
  30
  31 ;;; Commentary:
  32 ;;
  33 ;; Boring old c-mode.el (BOCM) is confusion and brain melt. cc-mode.el
  34 ;; is clarity of thought and purity of chi. If you are still unwilling
  35 ;; to accept enlightenment, this might help, or it may prolong your
  36 ;; agony.
  37 ;;
  38 ;; To use, add the following to your c-mode-hook:
  39 ;;
  40 ;; (require 'cc-compat)
  41 ;; (c-set-style "BOCM")
  42 ;;
  43 ;; This file is completely unsupported!  Although it has been patched
  44 ;; superficially to keep pace with the rest of CC Mode, it hasn't been
  45 ;; tested for a long time.
  46
  47 ;;; Code:
  48
  49 (eval-when-compile
  50   (let ((load-path
  51          (if (and (boundp 'byte-compile-dest-file)
  52                   (stringp byte-compile-dest-file))
  53              (cons (file-name-directory byte-compile-dest-file) load-path)
  54            load-path)))
  55     (load "cc-bytecomp" nil t)))
  56
  57 (cc-require 'cc-defs)
  58 (cc-require 'cc-vars)
  59 (cc-require 'cc-styles)
  60 (cc-require 'cc-engine)
  61
  62 \f
  63 ;; In case c-mode.el isn't loaded
  64 (defvar c-indent-level 2
  65   "*Indentation of C statements with respect to containing block.")
  66 ;;;###autoload(put 'c-indent-level 'safe-local-variable 'integerp)
  67
  68 (defvar c-brace-imaginary-offset 0
  69   "*Imagined indentation of a C open brace that actually follows a statement.")
  70 (defvar c-brace-offset 0
  71   "*Extra indentation for braces, compared with other text in same context.")
  72 (defvar c-argdecl-indent 5
  73   "*Indentation level of declarations of C function arguments.")
  74 (defvar c-label-offset -2
  75   "*Offset of C label lines and case statements relative to usual indentation.")
  76 (defvar c-continued-statement-offset 2
  77   "*Extra indent for lines not starting new statements.")
  78 (defvar c-continued-brace-offset 0
  79   "*Extra indent for substatements that start with open-braces.
  80 This is in addition to c-continued-statement-offset.")
  81
  82
  83 \f
  84 ;; these offsets are taken by brute force testing c-mode.el, since
  85 ;; there's no logic to what it does.
  86 (let* ((offsets '(c-offsets-alist .
  87                     ((defun-block-intro     . cc-block-intro-offset)
  88                      (statement-block-intro . cc-block-intro-offset)
  89                      (defun-open            . 0)
  90                      (class-open            . 0)
  91                      (inline-open           . c-brace-offset)
  92                      (block-open            . c-brace-offset)
  93                      (block-close           . cc-block-close-offset)
  94                      (brace-list-open       . c-brace-offset)
  95                      (substatement-open     . cc-substatement-open-offset)
  96                      (substatement          . c-continued-statement-offset)
  97                      (knr-argdecl-intro     . c-argdecl-indent)
  98                      (case-label            . c-label-offset)
  99                      (access-label          . c-label-offset)
 100                      (label                 . c-label-offset)
 101                      ))))
 102   (c-add-style "BOCM" offsets))
 103
 104
 105 (defun cc-block-intro-offset (langelem)
 106   ;; taken directly from calculate-c-indent confusion
 107   (save-excursion
 108     (c-backward-syntactic-ws)
 109     (if (eq (char-before) ?{)
 110         (forward-char -1)
 111       (goto-char (cdr langelem)))
 112     (let* ((curcol (save-excursion
 113                      (goto-char (cdr langelem))
 114                      (current-column)))
 115           (bocm-lossage
 116            ;; If no previous statement, indent it relative to line
 117            ;; brace is on.  For open brace in column zero, don't let
 118            ;; statement start there too.  If c-indent-level is zero,
 119            ;; use c-brace-offset + c-continued-statement-offset
 120            ;; instead.  For open-braces not the first thing in a line,
 121            ;; add in c-brace-imaginary-offset.
 122            (+ (if (and (bolp) (zerop c-indent-level))
 123                   (+ c-brace-offset c-continued-statement-offset)
 124                 c-indent-level)
 125               ;; Move back over whitespace before the openbrace.  If
 126               ;; openbrace is not first nonwhite thing on the line,
 127               ;; add the c-brace-imaginary-offset.
 128               (progn (skip-chars-backward " \t")
 129                      (if (bolp) 0 c-brace-imaginary-offset))
 130               ;; If the openbrace is preceded by a parenthesized exp,
 131               ;; move to the beginning of that; possibly a different
 132               ;; line
 133               (progn
 134                 (if (eq (char-before) ?\))
 135                     (c-forward-sexp -1))
 136                 ;; Get initial indentation of the line we are on.
 137                 (current-indentation)))))
 138       (- bocm-lossage curcol))))
 139
 140
 141 (defun cc-block-close-offset (langelem)
 142   (save-excursion
 143     (let* ((here (point))
 144            bracep
 145            (curcol (progn
 146                      (goto-char (cdr langelem))
 147                      (current-column)))
 148            (bocm-lossage (progn
 149                            (goto-char (cdr langelem))
 150                            (if (eq (char-after) ?{)
 151                                (setq bracep t)
 152                              (goto-char here)
 153                              (beginning-of-line)
 154                              (backward-up-list 1)
 155                              (forward-char 1)
 156                              (c-forward-syntactic-ws))
 157                            (current-column))))
 158       (- bocm-lossage curcol
 159          (if bracep 0 c-indent-level)))))
 160
 161
 162 (defun cc-substatement-open-offset (langelem)
 163   (+ c-continued-statement-offset c-continued-brace-offset))
 164
 165 \f
 166 (cc-provide 'cc-compat)
 167
 168 ;; arch-tag: 564dab2f-e6ad-499c-a4a3-fedec3ecc192
 169 ;;; cc-compat.el ends here