Re: [PATCH] checkpatch: get CONFIG_ prefix from the environment

[Joe Perches <joe@perches.com>]

On Mon, 2020-08-17 at 11:50 +0200, Jerome Forissier wrote:
> Kconfig allows to customize the CONFIG_ prefix via the $CONFIG_
> environment variable. Out-of-tree projects may therefore use Kconfig
> with a different prefix, or they may use a custom configuration tool
> which does not use the CONFIG_ prefix at all. Such projects may still
> want to adhere to the Linux kernel coding style and run checkpatch.pl.
> To make this possible, update checkpatch to use the value of $CONFIG_
> if defined or "CONFIG_" otherwise.
> 
> Signed-off-by: Jerome Forissier <jerome@forissier.org>
> ---
>  scripts/checkpatch.pl | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index 2cbeae6d9aee..2cf750175a71 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -65,6 +65,7 @@ my $allow_c99_comments = 1; # Can be overridden by --ignore C99_COMMENT_TOLERANC
>  # git output parsing needs US English output, so first set backtick child process LANGUAGE
>  my $git_command ='export LANGUAGE=en_US.UTF-8; git';
>  my $tabsize = 8;
> +my $CONFIG_ = $ENV{"CONFIG_"} || "CONFIG_";

I'm not a big fan of environment variable being
used to control program behavior.

Maybe add something to .checkpatch.conf instead.

>  sub help {
>  	my ($exitcode) = @_;
> @@ -6528,16 +6529,16 @@ sub process {
>  		}
>  
>  # check for IS_ENABLED() without CONFIG_<FOO> ($rawline for comments too)
> -		if ($rawline =~ /\bIS_ENABLED\s*\(\s*(\w+)\s*\)/ && $1 !~ /^CONFIG_/) {
> +		if ($rawline =~ /\bIS_ENABLED\s*\(\s*(\w+)\s*\)/ && $1 !~ /^$CONFIG_/) {
>  			WARN("IS_ENABLED_CONFIG",
> -			     "IS_ENABLED($1) is normally used as IS_ENABLED(CONFIG_$1)\n" . $herecurr);
> +			     "IS_ENABLED($1) is normally used as IS_ENABLED($CONFIG_$1)\n" . $herecurr);
>  		}
>  
>  # check for #if defined CONFIG_<FOO> || defined CONFIG_<FOO>_MODULE
> -		if ($line =~ /^\+\s*#\s*if\s+defined(?:\s*\(?\s*|\s+)(CONFIG_[A-Z_]+)\s*\)?\s*\|\|\s*defined(?:\s*\(?\s*|\s+)\1_MODULE\s*\)?\s*$/) {
> +		if ($line =~ /^\+\s*#\s*if\s+defined(?:\s*\(?\s*|\s+)($CONFIG_[A-Z_]+)\s*\)?\s*\|\|\s*defined(?:\s*\(?\s*|\s+)\1_MODULE\s*\)?\s*$/) {
>  			my $config = $1;
>  			if (WARN("PREFER_IS_ENABLED",
> -				 "Prefer IS_ENABLED(<FOO>) to CONFIG_<FOO> || CONFIG_<FOO>_MODULE\n" . $herecurr) &&
> +				 "Prefer IS_ENABLED(<FOO>) to $CONFIG_<FOO> || $CONFIG_<FOO>_MODULE\n" . $herecurr) &&
>  			    $fix) {
>  				$fixed[$fixlinenr] = "\+#if IS_ENABLED($config)";
>  			}