From a7f371e54fac49ff62bb640d4a7276fca01527e8 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Fri, 25 Jul 2008 01:45:51 -0700 Subject: [PATCH] documentation: update CodingStyle tips for Emacs users Describe a setup that integrates better with Emacs' cc-mode and also fixes up the alignment of continuation lines to really only use tabs. Signed-off-by: Johannes Weiner Cc: Jonathan Corbet Cc: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/CodingStyle | 42 +++++++++++++++++++++------------------ 1 file changed, 23 insertions(+), 19 deletions(-) diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle index 6caa146155..1875e502f8 100644 --- a/Documentation/CodingStyle +++ b/Documentation/CodingStyle @@ -474,25 +474,29 @@ make a good program). So, you can either get rid of GNU emacs, or change it to use saner values. To do the latter, you can stick the following in your .emacs file: -(defun linux-c-mode () - "C mode with adjusted defaults for use with the Linux kernel." - (interactive) - (c-mode) - (c-set-style "K&R") - (setq tab-width 8) - (setq indent-tabs-mode t) - (setq c-basic-offset 8)) - -This will define the M-x linux-c-mode command. When hacking on a -module, if you put the string -*- linux-c -*- somewhere on the first -two lines, this mode will be automatically invoked. Also, you may want -to add - -(setq auto-mode-alist (cons '("/usr/src/linux.*/.*\\.[ch]$" . linux-c-mode) - auto-mode-alist)) - -to your .emacs file if you want to have linux-c-mode switched on -automagically when you edit source files under /usr/src/linux. +(defun c-lineup-arglist-tabs-only (ignored) + "Line up argument lists by tabs, not spaces" + (let* ((anchor (c-langelem-pos c-syntactic-element)) + (column (c-langelem-2nd-pos c-syntactic-element)) + (offset (- (1+ column) anchor)) + (steps (floor offset c-basic-offset))) + (* (max steps 1) + c-basic-offset))) + +(add-hook 'c-mode-hook + (lambda () + (let ((filename (buffer-file-name))) + ;; Enable kernel mode for the appropriate files + (when (and filename + (string-match "~/src/linux-trees" filename)) + (setq indent-tabs-mode t) + (c-set-style "linux") + (c-set-offset 'arglist-cont-nonempty + '(c-lineup-gcc-asm-reg + c-lineup-arglist-tabs-only)))))) + +This will make emacs go better with the kernel coding style for C +files below ~/src/linux-trees. But even if you fail in getting emacs to do sane formatting, not everything is lost: use "indent". -- 2.39.5