On 9/14/20 7:26 PM, Dov Murik wrote:
> According to the coding style document, we should use literal '0x' prefix
> instead of printf's '#' flag (which appears as '%#' or '%0#' in the format
> string). Add a checkpatch rule to enforce that.
>
> Note that checkpatch already had a similar rule for trace-events files.
>
> Example usage:
>
> $ scripts/checkpatch.pl --file chardev/baum.c
> ...
> ERROR: Don't use '#' flag of printf format ('%#') in format strings, use
> '0x' prefix instead
> #366: FILE: chardev/baum.c:366:
> + DPRINTF("Broken packet %#2x, tossing\n", req); \
> ...
> ERROR: Don't use '#' flag of printf format ('%#') in format strings, use
> '0x' prefix instead
> #472: FILE: chardev/baum.c:472:
> + DPRINTF("unrecognized request %0#2x\n", req);
> ...
>
> Signed-off-by: Dov Murik <dovmu...@linux.vnet.ibm.com>
> ---
>
> Since v1:
> - consolidate format string checks to avoid code duplication
>
> ---
> scripts/checkpatch.pl | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index bd3faa154c..f8dac953b2 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2880,14 +2880,20 @@ sub process {
> $herecurr);
> }
>
> -# check for %L{u,d,i} in strings
> +# format strings checks
> my $string;
> while ($line =~ /(?:^|")([X\t]*)(?:"|$)/g) {
> $string = substr($rawline, $-[1], $+[1] - $-[1]);
> $string =~ s/%%/__/g;
> + # check for %L{u,d,i} in strings
> if ($string =~ /(?<!%)%L[udi]/) {
> ERROR("\%Ld/%Lu are not-standard C, use
> %lld/%llu\n" . $herecurr);
> - last;
> + }
> + # check for %# or %0# in printf-style format strings
> + if ($string =~ /(?<!%)%0?#/) {
> + ERROR("Don't use '#' flag of printf format " .
> + "('%#') in format strings, use '0x' " .
> + "prefix instead\n" . $herecurr);
> }
> }
>
>
Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>
