| Message ID | 20200914060109.69583-1-dovmurik@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | checkpatch: Detect '%#' or '%0#' in printf-style format strings | expand |
On 14/09/20 15:00, Philippe Mathieu-Daudé wrote: >> That makes sense, except that 'last' statement which will escape the >> loop if one of the bad patterns is found. >> >> Maybe we can just drop 'last' from both if-then blocks? We'll get >> multiple alerts if bad patterns are used more than once in the same >> line, which sounds OK to me. > No objection. > Sounds good. Paolo
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index bd3faa154c..6ec2a9f6a1 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -2891,6 +2891,18 @@ sub process { } } +# check for %# or %0# in printf-style format strings + while ($line =~ /(?:^|")([X\t]*)(?:"|$)/g) { + my $string = substr($rawline, $-[1], $+[1] - $-[1]); + $string =~ s/%%/__/g; + if ($string =~ /(?<!%)%0?#/) { + ERROR("Don't use '#' flag of printf format " . + "('%#') in format strings, use '0x' " . + "prefix instead\n" . $herecurr); + last; + } + } + # QEMU specific tests if ($rawline =~ /\b(?:Qemu|QEmu)\b/) { ERROR("use QEMU instead of Qemu or QEmu\n" . $herecurr);
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 <dovmurik@linux.vnet.ibm.com> --- scripts/checkpatch.pl | 12 ++++++++++++ 1 file changed, 12 insertions(+)