lisp/progmodes/cc-compat.el

   1 ;;; cc-compat.el --- cc-mode compatibility with c-mode.el confusion
   2
   3 ;; Copyright (C) 1985,1987,1992-2000 Free Software Foundation, Inc.
   4
   5 ;; Authors:    2000- Martin Stjernholm
   6 ;;             1998-1999 Barry A. Warsaw and Martin Stjernholm
   7 ;;             1994-1997 Barry A. Warsaw
   8 ;; Maintainer: bug-cc-mode@gnu.org
   9 ;; Created:    August 1994, split from cc-mode.el
  10 ;; Version:    See cc-mode.el
  11 ;; Keywords:   c languages oop
  12
  13 ;; This file is part of GNU Emacs.
  14
  15 ;; GNU Emacs is free software; you can redistribute it and/or modify
  16 ;; it under the terms of the GNU General Public License as published by
  17 ;; the Free Software Foundation; either version 2, or (at your option)
  18 ;; any later version.
  19
  20 ;; GNU Emacs is distributed in the hope that it will be useful,
  21 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 ;; GNU General Public License for more details.
  24
  25 ;; You should have received a copy of the GNU General Public License
  26 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  27 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  28 ;; Boston, MA 02111-1307, USA.
  29
  30 ;;; Commentary:
  31 ;;
  32 ;; Boring old c-mode.el (BOCM) is confusion and brain melt. cc-mode.el
  33 ;; is clarity of thought and purity of chi. If you are still unwilling
  34 ;; to accept enlightenment, this might help, or it may prolong your
  35 ;; agony.
  36 ;;
  37 ;; To use, add the following to your c-mode-hook:
  38 ;;
  39 ;; (require 'cc-compat)
  40 ;; (c-set-style "BOCM")
  41
  42 ;;; Code:
  43
  44 (eval-when-compile
  45   (let ((load-path
  46          (if (and (boundp 'byte-compile-current-file)
  47                   (stringp byte-compile-current-file))
  48              (cons (file-name-directory byte-compile-current-file)
  49                    load-path)
  50            load-path)))
  51     (load "cc-defs" nil t)))
  52 (require 'cc-styles)
  53 (require 'cc-engine)
  54
  55 \f
  56 ;; In case c-mode.el isn't loaded
  57 (defvar c-indent-level 2
  58   "*Indentation of C statements with respect to containing block.")
  59 (defvar c-brace-imaginary-offset 0
  60   "*Imagined indentation of a C open brace that actually follows a statement.")
  61 (defvar c-brace-offset 0
  62   "*Extra indentation for braces, compared with other text in same context.")
  63 (defvar c-argdecl-indent 5
  64   "*Indentation level of declarations of C function arguments.")
  65 (defvar c-label-offset -2
  66   "*Offset of C label lines and case statements relative to usual indentation.")
  67 (defvar c-continued-statement-offset 2
  68   "*Extra indent for lines not starting new statements.")
  69 (defvar c-continued-brace-offset 0
  70   "*Extra indent for substatements that start with open-braces.
  71 This is in addition to c-continued-statement-offset.")
  72
  73
  74 \f
  75 ;; these offsets are taken by brute force testing c-mode.el, since
  76 ;; there's no logic to what it does.
  77 (let* ((offsets '(c-offsets-alist .
  78                     ((defun-block-intro     . cc-block-intro-offset)
  79                      (statement-block-intro . cc-block-intro-offset)
  80                      (defun-open            . 0)
  81                      (class-open            . 0)
  82                      (inline-open           . c-brace-offset)
  83                      (block-open            . c-brace-offset)
  84                      (block-close           . cc-block-close-offset)
  85                      (brace-list-open       . c-brace-offset)
  86                      (substatement-open     . cc-substatement-open-offset)
  87                      (substatement          . c-continued-statement-offset)
  88                      (knr-argdecl-intro     . c-argdecl-indent)
  89                      (case-label            . c-label-offset)
  90                      (access-label          . c-label-offset)
  91                      (label                 . c-label-offset)
  92                      ))))
  93   (c-add-style "BOCM" offsets))
  94
  95
  96 (defun cc-block-intro-offset (langelem)
  97   ;; taken directly from calculate-c-indent confusion
  98   (save-excursion
  99     (c-backward-syntactic-ws)
 100     (if (eq (char-before) ?{)
 101         (forward-char -1)
 102       (goto-char (cdr langelem)))
 103     (let* ((curcol (save-excursion
 104                      (goto-char (cdr langelem))
 105                      (current-column)))
 106           (bocm-lossage
 107            ;; If no previous statement, indent it relative to line
 108            ;; brace is on.  For open brace in column zero, don't let
 109            ;; statement start there too.  If c-indent-level is zero,
 110            ;; use c-brace-offset + c-continued-statement-offset
 111            ;; instead.  For open-braces not the first thing in a line,
 112            ;; add in c-brace-imaginary-offset.
 113            (+ (if (and (bolp) (zerop c-indent-level))
 114                   (+ c-brace-offset c-continued-statement-offset)
 115                 c-indent-level)
 116               ;; Move back over whitespace before the openbrace.  If
 117               ;; openbrace is not first nonwhite thing on the line,
 118               ;; add the c-brace-imaginary-offset.
 119               (progn (skip-chars-backward " \t")
 120                      (if (bolp) 0 c-brace-imaginary-offset))
 121               ;; If the openbrace is preceded by a parenthesized exp,
 122               ;; move to the beginning of that; possibly a different
 123               ;; line
 124               (progn
 125                 (if (eq (char-before) ?\))
 126                     (c-forward-sexp -1))
 127                 ;; Get initial indentation of the line we are on.
 128                 (current-indentation)))))
 129       (- bocm-lossage curcol))))
 130
 131
 132 (defun cc-block-close-offset (langelem)
 133   (save-excursion
 134     (let* ((here (point))
 135            bracep
 136            (curcol (progn
 137                      (goto-char (cdr langelem))
 138                      (current-column)))
 139            (bocm-lossage (progn
 140                            (goto-char (cdr langelem))
 141                            (if (eq (char-after) ?{)
 142                                (setq bracep t)
 143                              (goto-char here)
 144                              (beginning-of-line)
 145                              (backward-up-list 1)
 146                              (forward-char 1)
 147                              (c-forward-syntactic-ws))
 148                            (current-column))))
 149       (- bocm-lossage curcol
 150          (if bracep 0 c-indent-level)))))
 151
 152
 153 (defun cc-substatement-open-offset (langelem)
 154   (+ c-continued-statement-offset c-continued-brace-offset))
 155
 156 \f
 157 (provide 'cc-compat)
 158 ;;; cc-compat.el ends here