Re: [Xen-devel] [PATCH v2] Document the coding style conventions.

[Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>]

On Mon, 19 Mar 2012, David Vrabel wrote:
> From: David Vrabel <david.vrabel@xxxxxxxxxx>
> 
> Based on a version originally posted in 2007.
> http://lists.xen.org/archives/html/xen-devel/2007-06/msg00070.html
> 
> Signed-off-by: David Vrabel <david.vrabel@xxxxxxxxxx>
> ---
> Changes since v1:
>   - renamed to CODING_STYLE
>   - intro text from Ian C.
>   - line length section
>   - expanded bracing example.
> 
> Not changed since v1:
>   - braces around single statement still 'should' not 'may'.
> ---
>  CODING_STYLE |  120 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 120 insertions(+), 0 deletions(-)
>  create mode 100644 CODING_STYLE
> 
> diff --git a/CODING_STYLE b/CODING_STYLE
> new file mode 100644
> index 0000000..95842e3
> --- /dev/null
> +++ b/CODING_STYLE
> @@ -0,0 +1,120 @@
> +Coding Style for the Xen Hypervisor
> +===================================
> +
> +The Xen coding style described below is the coding style used by the
> +Xen hypervisor itself (xen/*) as well as various associated low-level
> +libraries (e.g. tools/libxc/*).
> +        
> +An exception is made for files which are imported from an external
> +source. In these cases the prevailing coding style of the upstream
> +source is generally used (commonly the Linux coding style).
> +        
> +Other parts of the code base may use other coding styles, sometimes
> +explicitly (e.g. tools/libxl/CODING_STYLE) but often implicitly (Linux
> +coding style is fairly common). In general you should copy the style
> +of the surrounding code. If you are unsure please ask.
> +
> +Indentation
> +-----------
> +
> +Indenting uses spaces, not tabs - in contrast to Linux.  An indent
> +level consists of four spaces.  Code within blocks is indented by one
> +extra indent level.  The enclosing braces of a block are indented the
> +same as the code _outside_ the block.  e.g.
> +
> +void fun(void)
> +{
> +    /* One level of indent. */
> +
> +    {
> +        /* A second level of indent. */
> +    }
> +}
> +
> +White space
> +-----------
> +
> +Space characters are used to spread out logical statements, such as in
> +the condition of an if or while.  Spaces are placed between the
> +keyword and the brackets surrounding the condition, between the
> +brackets and the condition itself, and around binary operators (except
> +the structure access operators, '.' and '->'). e.g.
> +
> +if ( (wibble & wombat) == 42 )
> +{
> +    ...
> +
> +There should be no trailing white space at the end of lines (including
> +after the opening /* of a comment block).
> +
> +Line Length
> +-----------
> +
> +Lines should be less than 80 characters in length.  Long lines should
> +be split at sensible places and the trailing portions indented.
> +
> +User visible strings (e.g., printk() messages) should not be split so
> +they can searched for more easily.
> +
> +Bracing
> +-------
> +
> +Braces ('{' and '}') are usually placed on a line of their own, except
> +for the do/while loop.  This is unlike the Linux coding style and
> +unlike K&R.  do/while loops are an exception. e.g.:
> +
> +if ( condition )
> +{
> +    /* Do stuff. */
> +}
> +else
> +{
> +    /* Other stuff. */
> +}
> +
> +while ( condition )
> +{
> +    /* Do stuff. */
> +}
> +
> +do {
> +    /* Do stuff. */
> +} while ( condition );
> +
> +etc.
> +
> +Braces should be omitted for blocks with a single statement. e.g.,
> +
> +if ( condition )
> +    single_statement();
> +
> +Comments
> +--------
> +
> +Only C style /* ... */ comments are to be used.  C++ style // comments
> +should not be used.  Multi-word comments should begin with a capital
> +letter and end with a full stop.
> +
> +Multi-line comment blocks should start and end with comment markers on
> +separate lines and each line should begin with a leading '*'.
> +
> +/*
> + * Example, multi-line comment block.
> + *
> + * Note beginning and end markers on separate lines and leading '*'.
> + */
> +
> +Emacs local variables
> +---------------------
> +
> +A comment block containing local variables for emacs is permitted at
> +the end of files.  It should be:
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * indent-tabs-mode: nil
> + * End:
> + */

vim comments should be allowed too?
We don't want to start a religious war, do we? ;-)

It think that the equivalent of the emacs comment would be:

/* vim: ts=4 et sw=4 */

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel