1 ;;; google-c-style.el --- Google's C/C++ style for c-mode 2 3 ;; Keywords: c, tools 4 5 ;; google-c-style.el is Copyright (C) 2008 Google Inc. All Rights Reserved. 6 ;; 7 ;; It is free software; you can redistribute it and/or modify it under the 8 ;; terms of either: 9 ;; 10 ;; a) the GNU General Public License as published by the Free Software 11 ;; Foundation; either version 1, or (at your option) any later version, or 12 ;; 13 ;; b) the "Artistic License". 14 15 ;;; Commentary: 16 17 ;; Provides the google C/C++ coding style. You may wish to add 18 ;; `google-set-c-style' to your `c-mode-common-hook' after requiring this 19 ;; file. For example: 20 ;; 21 ;; (add-hook 'c-mode-common-hook 'google-set-c-style) 22 ;; 23 ;; If you want the RETURN key to go to the next line and space over 24 ;; to the right place, add this to your .emacs right after the load-file: 25 ;; 26 ;; (add-hook 'c-mode-common-hook 'google-make-newline-indent) 27 28 ;;; Code: 29 30 ;; For some reason 1) c-backward-syntactic-ws is a macro and 2) under Emacs 22 31 ;; bytecode cannot call (unexpanded) macros at run time: 32 (eval-when-compile (require 'cc-defs)) 33 34 ;; Wrapper function needed for Emacs 21 and XEmacs (Emacs 22 offers the more 35 ;; elegant solution of composing a list of lineup functions or quantities with 36 ;; operators such as "add") 37 (defun google-c-lineup-expression-plus-4 (langelem) 38 "Indents to the beginning of the current C expression plus 4 spaces. 39 40 This implements title \"Function Declarations and Definitions\" 41 of the Google C++ Style Guide for the case where the previous 42 line ends with an open parenthese. 43 44 \"Current C expression\", as per the Google Style Guide and as 45 clarified by subsequent discussions, means the whole expression 46 regardless of the number of nested parentheses, but excluding 47 non-expression material such as \"if(\" and \"for(\" control 48 structures. 49 50 Suitable for inclusion in `c-offsets-alist'." 51 (save-excursion 52 (back-to-indentation) 53 ;; Go to beginning of *previous* line: 54 (c-backward-syntactic-ws) 55 (back-to-indentation) 56 (cond 57 ;; We are making a reasonable assumption that if there is a control 58 ;; structure to indent past, it has to be at the beginning of the line. 59 ((looking-at "\\(\\(if\\|for\\|while\\)\\s *(\\)") 60 (goto-char (match-end 1))) 61 ;; For constructor initializer lists, the reference point for line-up is 62 ;; the token after the initial colon. 63 ((looking-at ":\\s *") 64 (goto-char (match-end 0)))) 65 (vector (+ 4 (current-column))))) 66 67 ;;;###autoload 68 (defconst google-c-style 69 `((c-recognize-knr-p . nil) 70 (c-enable-xemacs-performance-kludge-p . t) ; speed up indentation in XEmacs 71 (c-basic-offset . 2) 72 (indent-tabs-mode . nil) 73 (c-comment-only-line-offset . 0) 74 (c-hanging-braces-alist . ((defun-open after) 75 (defun-close before after) 76 (class-open after) 77 (class-close before after) 78 (inexpr-class-open after) 79 (inexpr-class-close before) 80 (namespace-open after) 81 (inline-open after) 82 (inline-close before after) 83 (block-open after) 84 (block-close . c-snug-do-while) 85 (extern-lang-open after) 86 (extern-lang-close after) 87 (statement-case-open after) 88 (substatement-open after))) 89 (c-hanging-colons-alist . ((case-label) 90 (label after) 91 (access-label after) 92 (member-init-intro before) 93 (inher-intro))) 94 (c-hanging-semi&comma-criteria 95 . (c-semi&comma-no-newlines-for-oneline-inliners 96 c-semi&comma-inside-parenlist 97 c-semi&comma-no-newlines-before-nonblanks)) 98 (c-indent-comments-syntactically-p . t) 99 (comment-column . 40) 100 (c-indent-comment-alist . ((other . (space . 2)))) 101 (c-cleanup-list . (brace-else-brace 102 brace-elseif-brace 103 brace-catch-brace 104 empty-defun-braces 105 defun-close-semi 106 list-close-comma 107 scope-operator)) 108 (c-offsets-alist . ((arglist-intro google-c-lineup-expression-plus-4) 109 (func-decl-cont . ++) 110 (member-init-intro . ++) 111 (inher-intro . ++) 112 (comment-intro . 0) 113 (arglist-close . c-lineup-arglist) 114 (topmost-intro . 0) 115 (block-open . 0) 116 (inline-open . 0) 117 (substatement-open . 0) 118 (statement-cont 119 . 120 (,(when (fboundp 'c-no-indent-after-java-annotations) 121 'c-no-indent-after-java-annotations) 122 ,(when (fboundp 'c-lineup-assignments) 123 'c-lineup-assignments) 124 ++)) 125 (label . /) 126 (case-label . +) 127 (statement-case-open . +) 128 (statement-case-intro . +) ; case w/o { 129 (access-label . /) 130 (innamespace . 0)))) 131 "Google C/C++ Programming Style.") 132 133 ;;;###autoload 134 (defun google-set-c-style () 135 "Set the current buffer's c-style to Google C/C++ Programming 136 Style. Meant to be added to `c-mode-common-hook'." 137 (interactive) 138 (make-local-variable 'c-tab-always-indent) 139 (setq c-tab-always-indent t) 140 (c-add-style "Google" google-c-style t)) 141 142 ;;;###autoload 143 (defun google-make-newline-indent () 144 "Sets up preferred newline behavior. Not set by default. Meant 145 to be added to `c-mode-common-hook'." 146 (interactive) 147 (define-key c-mode-base-map "\C-m" 'newline-and-indent) 148 (define-key c-mode-base-map [ret] 'newline-and-indent)) 149 150 (provide 'google-c-style) 151 ;;; google-c-style.el ends here 152
