Re: [PATCH 8/8] docs: kernel-doc: Don't mangle literal code blocks in comments

From: Jani Nikula
Date: Wed Feb 14 2018 - 14:10:43 EST


On Wed, 14 Feb 2018, Jonathan Corbet <corbet@xxxxxxx> wrote:
> It can be useful to put code snippets into kerneldoc comments; that can be
> done with the "::" operator at the end of a line like this::
>
> if (desperate)
> run_in_circles();
>
> The ".. code-block::" directive can also be used to this end. kernel-doc
> currently fails to understand these literal blocks and applies its normal
> markup to them, which is then treated as literal by sphinx. The result is
> unsightly markup instead of a useful code snippet.
>
> Apply a hack to the output code to recognize literal blocks and avoid
> performing any special markup on them. It's ugly, but that means it fits
> in well with the rest of the script.

With emphasis on part (d) of the reviewer's statement of oversight,

Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>

>
> Signed-off-by: Jonathan Corbet <corbet@xxxxxxx>
> ---
> scripts/kernel-doc | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 64 insertions(+), 5 deletions(-)
>
> diff --git a/scripts/kernel-doc b/scripts/kernel-doc
> index fb8fbdb25036..cbe864e72a2f 100755
> --- a/scripts/kernel-doc
> +++ b/scripts/kernel-doc
> @@ -748,14 +748,73 @@ sub output_blockhead_rst(%) {
> }
> }
>
> -sub output_highlight_rst {
> - my $contents = join "\n",@_;
> - my $line;
> -
> +#
> +# Apply the RST highlights to a sub-block of text.
> +#
> +sub highlight_block($) {
> + # The dohighlight kludge requires the text be called $contents
> + my $contents = shift;
> eval $dohighlight;
> die $@ if $@;
> + return $contents;
> +}
>
> - foreach $line (split "\n", $contents) {
> +#
> +# Regexes used only here.
> +#
> +my $sphinx_literal = '^[^.].*::$';
> +my $sphinx_cblock = '^\.\.\ +code-block::';
> +
> +sub output_highlight_rst {
> + my $input = join "\n",@_;
> + my $output = "";
> + my $line;
> + my $in_literal = 0;
> + my $litprefix;
> + my $block = "";
> +
> + foreach $line (split "\n",$input) {
> + #
> + # If we're in a literal block, see if we should drop out
> + # of it. Otherwise pass the line straight through unmunged.
> + #
> + if ($in_literal) {
> + if (! ($line =~ /^\s*$/)) {
> + #
> + # If this is the first non-blank line in a literal
> + # block we need to figure out what the proper indent is.
> + #
> + if ($litprefix eq "") {
> + $line =~ /^(\s*)/;
> + $litprefix = '^' . $1;
> + $output .= $line . "\n";
> + } elsif (! ($line =~ /$litprefix/)) {
> + $in_literal = 0;
> + } else {
> + $output .= $line . "\n";
> + }
> + } else {
> + $output .= $line . "\n";
> + }
> + }
> + #
> + # Not in a literal block (or just dropped out)
> + #
> + if (! $in_literal) {
> + $block .= $line . "\n";
> + if (($line =~ /$sphinx_literal/) || ($line =~ /$sphinx_cblock/)) {
> + $in_literal = 1;
> + $litprefix = "";
> + $output .= highlight_block($block);
> + $block = ""
> + }
> + }
> + }
> +
> + if ($block) {
> + $output .= highlight_block($block);
> + }
> + foreach $line (split "\n", $output) {
> print $lineprefix . $line . "\n";
> }
> }

--
Jani Nikula, Intel Open Source Technology Center