Hello, ping... 2016-01-27 19:51 GMT-03:00 Geyslan G. Bem <geyslan@xxxxxxxxx>: > This patch adds kernel-dot-emacs.txt (elisp) which deliver best > indentation, comments and white space highlighting functionalities. > > This also changes the CodingStyle and 00-INDEX files by referencing > the new kernel-dot-emacs. > > Signed-off-by: Geyslan G. Bem <geyslan@xxxxxxxxx> > --- > > Notes: > This patch was done by suggestion of Jonathan Corbet: > http://thread.gmane.org/gmane.linux.documentation/35265/focus=35309 > > Documentation/00-INDEX | 2 + > Documentation/CodingStyle | 38 +---- > Documentation/kernel-dot-emacs.txt | 285 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 291 insertions(+), 34 deletions(-) > create mode 100644 Documentation/kernel-dot-emacs.txt > > diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX > index cd077ca..d4c48f5 100644 > --- a/Documentation/00-INDEX > +++ b/Documentation/00-INDEX > @@ -259,6 +259,8 @@ kernel-doc-nano-HOWTO.txt > - mini HowTo on generation and location of kernel documentation files. > kernel-docs.txt > - listing of various WWW + books that document kernel internals. > +kernel-dot-emacs.txt > + - emacs dot file for kernel coding style. > kernel-parameters.txt > - summary listing of command line / boot prompt args for the kernel. > kernel-per-CPU-kthreads.txt > diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle > index c06f817..4d64b58 100644 > --- a/Documentation/CodingStyle > +++ b/Documentation/CodingStyle > @@ -501,40 +501,10 @@ typing - an infinite number of monkeys typing into GNU emacs would never > 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 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-common-hook > - (lambda () > - ;; Add kernel style > - (c-add-style > - "linux-tabs-only" > - '("linux" (c-offsets-alist > - (arglist-cont-nonempty > - c-lineup-gcc-asm-reg > - c-lineup-arglist-tabs-only)))))) > - > -(add-hook 'c-mode-hook > - (lambda () > - (let ((filename (buffer-file-name))) > - ;; Enable kernel mode for the appropriate files > - (when (and filename > - (string-match (expand-file-name "~/src/linux-trees") > - filename)) > - (setq indent-tabs-mode t) > - (setq show-trailing-whitespace t) > - (c-set-style "linux-tabs-only"))))) > - > -This will make emacs go better with the kernel coding style for C > -files below ~/src/linux-trees. > +values. To do the latter, you can stick the elisp code from > +Documentation/kernel-dot-emacs.txt in your emacs init file. 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". > diff --git a/Documentation/kernel-dot-emacs.txt b/Documentation/kernel-dot-emacs.txt > new file mode 100644 > index 0000000..b6d6816 > --- /dev/null > +++ b/Documentation/kernel-dot-emacs.txt > @@ -0,0 +1,285 @@ > +;; Kernel dot emacs > +;; Based on the prior elisp from Documentantion/CodingStyle > +;; > +;; January, 2016 > +;; Geyslan G. Bem <geyslan@xxxxxxxxx> > + > +;; This elisp does use of emacs functionalities which deliver to the > +;; user indentation, comments and white space highlighting. > +;; > +;; As known tabs are the higher law and the prior elisp code enforces > +;; that law for any lineup indentation. > +;; > +;; However some trees have specific rules about line continuation > +;; indentation. Even scripts/checkpatch.pl suggests the TABS+SPACES (lining up > +;; under the open paren) for lineup the sequential lines. > +;; > +;; In addition to allowing the automatic setup by tree, this elisp can easily > +;; be modified for new configurations. Eg. > +;; > +;; (when (or (string-match (concat source-path "/net") filename) > +;; (string-match (concat source-path "/drivers/net") filename)) > +;; (setup-kernel-style 'extra-bottom-line t nil)) > +;; > +;; The above model can be used for a new tree just changing the tree path > +;; and parameters of setup-kernel-style function. > +;; > +;; setup-kernel-style function sets the kernel-comment-style, > +;; kernel-lineup-tabs-only and kernel-lineup-maximum-tabs variables. They > +;; are used by the functions kernel-comment-dwim and kernel-lineup-arglist. > +;; > +;; The kernel-lineup-arglist function detects the maximum tabs allowed to > +;; lineup and if it must use tabs and spaces instead of only tabs. > +;; > +;; There are two cleanups for else and else if braces enabled when > +;; auto-newline is on. These are comfortable and avoid wrong coding > +;; style. For instance > +;; > +;; void spam(int i) > +;; { > +;; if (i == 7) { > +;; dosomething(); > +;; ... > +;; } > +;; else > +;; { > +;; appears like this after the last open brace is typed: > +;; > +;; void spam(int i) > +;; { > +;; if (i == 7) { > +;; dosomething(); > +;; ... > +;; } else { > +;; > +;; The same happens for else if opening braces. > +;; > +;; The function kernel-align-to-equals makes the aligning of variable > +;; initializations/assignments easier. > +;; > +;; int x = 10; > +;; char *str = "text"; > +;; x = 100; > +;; > +;; After marked the region and pressed C-c a = > +;; > +;; int x = 10; > +;; char *str = "text"; > +;; x = 100; > +;; > +;; Concerning to comments kernel-comment-dwim is an improved version of > +;; comment-dwim. It comment/uncomment lines, regions or adds a new > +;; indented comment after the code using the same key binding. Eg. > +;; > +;; void f(int x, int y); > +;; > +;; Press M-; in any position on the line for > +;; > +;; void f(int x, int y); /* */ > +;; > +;; Press M-; again for > +;; > +;; /* void f(int x, int y); */ > +;; > +;; Press M-; and again for > +;; > +;; void f(int x, int y); > +;; > +;; For multi-line comments the result is > +;; > +;; /* > +;; * void f1(int x, int y); > +;; * void f2(int x, int y); > +;; */ > +;; > +;; Emacs doesn't provide yet a 'net' comment style by default. This code > +;; also does the magic when kernel-comment-style is set as 'extra-bottom-line. > +;; > +;; /* void f1(int x, int y); > +;; * void f2(int x, int y); > +;; */ > +;; > +;; Until now the comment-region doesn't tabify the comment, generating > +;; spaces before the " * " comment-continue variable (this issue was > +;; reported and patched in the to be released emacs-25) however this code > +;; correctly tabify the commented result. > +;; > +;; kernel-comment-dwim also removes trailing white spaces created by the > +;; comment-region. > +;; > +;; Finally the white space highlighting is a must to alert about long > +;; lines, leading or trailing spaces and top or bottom empty lines. > + > + > +(defconst kernel-column-limit 80 > + "It is only 80, get over it.") > + > +(defvar kernel-source-path "~/src/linux-trees" > + "The kernel source path.") > + > +(defvar kernel-comment-style 'extra-lines > + "Default style is 'extra-lines. > +The another option is 'extra-bottom-line") > +(make-variable-buffer-local 'kernel-comment-style) > + > +(defvar kernel-lineup-tabs-only nil > + "If it is non-nil the kernel lineup indentation will make use of tabs only. > +When nil lineup indentation will use TABS + SPACES.") > +(make-variable-buffer-local 'kernel-lineup-tabs-only) > + > +(defvar kernel-lineup-maximum-tabs nil > + "If it is non-nil its value will be the maximum tabs steps in kernel lineup > +indentation. > +When nil there will not be such a limit. > +In both cases there is also the maximum limit forced by the > +`kernel-lineup-arglist' function in conjuction with the > +`kernel-column-limit' constant.") > +(make-variable-buffer-local 'kernel-lineup-maximum-tabs) > + > +(defun setup-kernel-style (comment-style lineup-tabs-only lineup-maximum-tabs) > + (setq kernel-comment-style comment-style) > + (setq kernel-lineup-tabs-only lineup-tabs-only) > + (setq kernel-lineup-maximum-tabs lineup-maximum-tabs)) > + > +(defun kernel-comment-dwim () > + "Comments or uncomments the region. > +If there's no active region adds/indents an one line comment or > +comments/uncomments the current line if the one line comment is > +empty." > + (interactive) > + (let (beg end) > + (if (region-active-p) > + (progn > + (setq beg (region-beginning) > + end (region-end)) > + (if (comment-only-p beg end) > + (uncomment-region beg end) > + (progn > + (comment-region beg end) > + (save-excursion > + (goto-char beg) > + ;; Remove extra top line > + (when (equal kernel-comment-style 'extra-bottom-line) > + (re-search-forward "/\\*\\s-*\n\\s-*\\(\\*\\)" end t) > + (replace-match "/\\1")) > + ;; Update end point > + (goto-char beg) > + (re-search-forward "\\*/" nil t) > + (setq end (point)) > + ;; This error is fixed in version 25. > + (when (< emacs-major-version 25) > + (tabify beg end)) > + ;; Cleaning only trailing spaces inserted by comment-region. > + ;; Existing ones are not touched. > + (goto-char beg) > + (while (re-search-forward > + "\\(/+\\|^\\s-+\\)\\(\\*\\)\\(\\s-+$\\)" end t nil) > + (replace-match "\\1\\2") > + (save-excursion > + (re-search-forward "\\*/" nil t 1) > + (setq end (point)))))))) > + (progn > + (setq beg (line-beginning-position) > + end (line-end-position)) > + (if (save-excursion > + (goto-char beg) > + (looking-at "\\s-*$")) > + (progn > + (comment-indent) > + (indent-according-to-mode)) > + (if (comment-only-p beg end) > + (uncomment-region beg end) > + (if (save-excursion > + (goto-char beg) > + (re-search-forward "/\\*\\s-+\\*/" end t 1)) > + (progn > + (save-excursion > + (goto-char beg) > + (let (kill-ring) > + (comment-kill nil))) > + ;; Read end position directly > + (comment-region beg (line-end-position))) > + (comment-indent)))))))) > + > +(defun kernel-align-to-equals (begin end) > + "Align region to equal signs" > + (interactive "r") > + (align-regexp begin end "\\(\\s-*\\)=" 1 1 nil)) > + > +(defun kernel-lineup-arglist (langelem) > + "" > + (let* ((ret (c-lineup-arglist langelem)) > + (anchor (c-langelem-pos c-syntactic-element)) > + (column (c-langelem-2nd-pos c-syntactic-element)) > + (offset (- (1+ column) anchor)) > + (newcol (c-langelem-col langelem t)) > + (steps (floor offset c-basic-offset))) > + (if (not kernel-lineup-tabs-only) > + ret > + (progn > + (when (>= (+ newcol (* c-basic-offset steps)) > + kernel-column-limit) > + (setq steps (1- steps))) > + (when kernel-lineup-maximum-tabs > + (setq steps (min steps > + kernel-lineup-maximum-tabs))) > + (* (max steps 1) c-basic-offset))))) > + > +(add-hook 'c-mode-common-hook > + (lambda () > + (c-add-style > + "linux-kernel" > + '("linux" (c-offsets-alist > + (arglist-cont-nonempty > + c-lineup-gcc-asm-reg > + kernel-lineup-arglist) > + (c-cleanup-list brace-else-brace > + brace-elseif-brace)))))) > + > +(defun kernel-style-hook () > + (let ((filename (buffer-file-name)) > + (source-path (expand-file-name kernel-source-path))) > + ;; Enable kernel mode for the appropriate files > + (when (and filename > + (string-match source-path filename)) > + ;; Setup style > + (c-set-style "linux-kernel") > + (setq tab-width 8 > + comment-style 'extra-line > + indent-tabs-mode t > + backward-delete-char-untabify-method nil) > + (c-toggle-auto-newline t) > + > + ;; Setup tree paths here > + (when (or (string-match (concat source-path "/net") filename) > + (string-match (concat source-path "/drivers/net") filename)) > + (setup-kernel-style 'extra-bottom-line t nil)) > + (when (string-match (concat source-path "/drivers/usb/host") filename) > + (setup-kernel-style 'extra-lines t 2)) > + > + ;; Set kernel style key bindings > + (local-set-key [remap comment-dwim] 'kernel-comment-dwim) > + (local-set-key (kbd "C-c a =") 'kernel-align-to-equals) > + ;; Setup white space highlighting > + (require 'whitespace) > + (setq whitespace-line-column kernel-column-limit > + whitespace-style '(face empty > + indentation::tab > + whitespace-space-before-tab > + space-before-tab::tab > + lines-tail > + trailing)) > + (dolist (face '(whitespace-line > + whitespace-indentation > + whitespace-space > + whitespace-space-before-tab > + whitespace-empty > + whitespace-trailing)) > + (set-face-background face "red")) > + (set-face-attribute whitespace-line nil > + :background "red" > + :foreground "yellow" > + :weight 'bold) > + (whitespace-mode t)))) > + > +(add-hook 'c-mode-hook 'kernel-style-hook) > -- > 2.7.0 > Any suggestion? -- Regards, Geyslan G. Bem hackingbits.com -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
