lisp/progmodes/cc-compat.el

   1 ;;; cc-compat.el --- cc-mode compatibility with c-mode.el confusion
   2
   3 ;; Copyright (C) 1985,1987,1992-1999 Free Software Foundation, Inc.
   4
   5 ;; Author:     1994-1997 Barry A. Warsaw
   6 ;; Maintainer: Unmaintained
   7 ;; Created:    August 1994, split from cc-mode.el
   8 ;; Version:    See cc-mode.el
   9 ;; Keywords:   c languages oop
  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 2, or (at your option)
  16 ;; 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; see the file COPYING.  If not, write to the
  25 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  26 ;; Boston, MA 02111-1307, USA.
  27
  28 ;;; Commentary:
  29 ;;
  30 ;; Boring old c-mode.el (BOCM) is confusion and brain melt. cc-mode.el
  31 ;; is clarity of thought and purity of chi. If you are still unwilling
  32 ;; to accept enlightenment, this might help, or it may prolong your
  33 ;; agony.
  34 ;;
  35 ;; To use, add the following to your c-mode-hook:
  36 ;;
  37 ;; (require 'cc-compat)
  38 ;; (c-set-style "BOCM")
  39
  40 ;;; Code:
  41
  42 (eval-when-compile
  43   (let ((load-path
  44          (if (and (boundp 'byte-compile-current-file)
  45                   (stringp byte-compile-current-file))
  46              (cons (file-name-directory byte-compile-current-file)
  47                    load-path)
  48            load-path)))
  49     (load "cc-defs" nil t)))
  50 (require 'cc-styles)
  51 (require 'cc-engine)
  52
  53 \f
  54 ;; In case c-mode.el isn't loaded
  55 (defvar c-indent-level 2
  56   "*Indentation of C statements with respect to containing block.")
  57 (defvar c-brace-imaginary-offset 0
  58   "*Imagined indentation of a C open brace that actually follows a statement.")
  59 (defvar c-brace-offset 0
  60   "*Extra indentation for braces, compared with other text in same context.")
  61 (defvar c-argdecl-indent 5
  62   "*Indentation level of declarations of C function arguments.")
  63 (defvar c-label-offset -2
  64   "*Offset of C label lines and case statements relative to usual indentation.")
  65 (defvar c-continued-statement-offset 2
  66   "*Extra indent for lines not starting new statements.")
  67 (defvar c-continued-brace-offset 0
  68   "*Extra indent for substatements that start with open-braces.
  69 This is in addition to c-continued-statement-offset.")
  70
  71
  72 \f
  73 ;; these offsets are taken by brute force testing c-mode.el, since
  74 ;; there's no logic to what it does.
  75 (let* ((offsets '(c-offsets-alist .
  76                     ((defun-block-intro     . cc-block-intro-offset)
  77                      (statement-block-intro . cc-block-intro-offset)
  78                      (defun-open            . 0)
  79                      (class-open            . 0)
  80                      (inline-open           . c-brace-offset)
  81                      (block-open            . c-brace-offset)
  82                      (block-close           . cc-block-close-offset)
  83                      (brace-list-open       . c-brace-offset)
  84                      (substatement-open     . cc-substatement-open-offset)
  85                      (substatement          . c-continued-statement-offset)
  86                      (knr-argdecl-intro     . c-argdecl-indent)
  87                      (case-label            . c-label-offset)
  88                      (access-label          . c-label-offset)
  89                      (label                 . c-label-offset)
  90                      ))))
  91   (c-add-style "BOCM" offsets))
  92
  93
  94 (defun cc-block-intro-offset (langelem)
  95   ;; taken directly from calculate-c-indent confusion
  96   (save-excursion
  97     (c-backward-syntactic-ws)
  98     (if (eq (char-before) ?{)
  99         (forward-char -1)
 100       (goto-char (cdr langelem)))
 101     (let* ((curcol (save-excursion
 102                      (goto-char (cdr langelem))
 103                      (current-column)))
 104           (bocm-lossage
 105            ;; If no previous statement, indent it relative to line
 106            ;; brace is on.  For open brace in column zero, don't let
 107            ;; statement start there too.  If c-indent-level is zero,
 108            ;; use c-brace-offset + c-continued-statement-offset
 109            ;; instead.  For open-braces not the first thing in a line,
 110            ;; add in c-brace-imaginary-offset.
 111            (+ (if (and (bolp) (zerop c-indent-level))
 112                   (+ c-brace-offset c-continued-statement-offset)
 113                 c-indent-level)
 114               ;; Move back over whitespace before the openbrace.  If
 115               ;; openbrace is not first nonwhite thing on the line,
 116               ;; add the c-brace-imaginary-offset.
 117               (progn (skip-chars-backward " \t")
 118                      (if (bolp) 0 c-brace-imaginary-offset))
 119               ;; If the openbrace is preceded by a parenthesized exp,
 120               ;; move to the beginning of that; possibly a different
 121               ;; line
 122               (progn
 123                 (if (eq (char-before) ?\))
 124                     (c-forward-sexp -1))
 125                 ;; Get initial indentation of the line we are on.
 126                 (current-indentation)))))
 127       (- bocm-lossage curcol))))
 128
 129
 130 (defun cc-block-close-offset (langelem)
 131   (save-excursion
 132     (let* ((here (point))
 133            bracep
 134            (curcol (progn
 135                      (goto-char (cdr langelem))
 136                      (current-column)))
 137            (bocm-lossage (progn
 138                            (goto-char (cdr langelem))
 139                            (if (eq (char-after) ?{)
 140                                (setq bracep t)
 141                              (goto-char here)
 142                              (beginning-of-line)
 143                              (backward-up-list 1)
 144                              (forward-char 1)
 145                              (c-forward-syntactic-ws))
 146                            (current-column))))
 147       (- bocm-lossage curcol
 148          (if bracep 0 c-indent-level)))))
 149
 150
 151 (defun cc-substatement-open-offset (langelem)
 152   (+ c-continued-statement-offset c-continued-brace-offset))
 153
 154 \f
 155 (provide 'cc-compat)
 156 ;;; cc-compat.el ends here