[PATCH v2] checkpatch: add command-line option for TAB size

Antonio Borneo
2019-05-08T17:44:12Z

The size of 8 characters used for both TAB and indentation is
embedded as magic value allover the checkpatch script, and this
makes the script less readable.

Replace the magic value 8 with a variable.
From the context of the code it's clear if it is used for
indentation or tabulation, so no need to use two separate
variables.

Add a command-line option "--tab-size" to let the user select a
TAB size value other than 8.
This makes easy to reuse this script by other projects with
different requirements in their coding style (e.g. OpenOCD [1]
requires TAB size of 4 characters [2]).

[1] http://openocd.org/
[2] http://openocd.org/doc/doxygen/html/stylec.html#styleformat

Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Signed-off-by: Erik Ahlén <erik.ahlen@avalonenterprise.com>
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
---
V1 -> V2
add the command line option

scripts/checkpatch.pl | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 916a3fbd4d47..90f641bf1895 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -62,6 +62,7 @@ my $conststructsfile = "$D/const_structs.checkpatch";
my $typedefsfile = "";
my $color = "auto";
my $allow_c99_comments = 1; # Can be overridden by --ignore C99_COMMENT_TOLERANCE
+my $tabsize = 8;

sub help {
my ($exitcode) = @_;
@@ -96,6 +97,7 @@ Options:
--show-types show the specific message type in the output
--max-line-length=n set the maximum line length, if exceeded, warn
--min-conf-desc-length=n set the min description length, if shorter, warn
+ --tab-size=n set the number of spaces for tab (default 8)
--root=PATH PATH to the kernel tree root
--no-summary suppress the per-file summary
--mailback only produce a report in case of warnings/errors
@@ -213,6 +215,7 @@ GetOptions(
'list-types!' => \$list_types,
'max-line-length=i' => \$max_line_length,
'min-conf-desc-length=i' => \$min_conf_desc_length,
+ 'tab-size=i' => \$tabsize,
'root=s' => \$root,
'summary!' => \$summary,
'mailback!' => \$mailback,
@@ -1211,7 +1214,7 @@ sub expand_tabs {
if ($c eq "\t") {
$res .= ' ';
$n++;
- for (; ($n % 8) != 0; $n++) {
+ for (; ($n % $tabsize) != 0; $n++) {
$res .= ' ';
}
next;
@@ -2224,7 +2227,7 @@ sub string_find_replace {
sub tabify {
my ($leading) = @_;

- my $source_indent = 8;
+ my $source_indent = $tabsize;
my $max_spaces_before_tab = $source_indent - 1;
my $spaces_to_tab = " " x $source_indent;

@@ -3153,7 +3156,7 @@ sub process {
next if ($realfile !~ /\.(h|c|pl|dtsi|dts)$/);

# at the beginning of a line any tabs must come first and anything
-# more than 8 must use tabs.
+# more than $tabsize must use tabs.
if ($rawline =~ /^\+\s* \t\s*\S/ ||
$rawline =~ /^\+\s* \s*/) {
my $herevet = "$here\n" . cat_vet($rawline) . "\n";
@@ -3172,7 +3175,7 @@ sub process {
"please, no space before tabs\n" . $herevet) &&
$fix) {
while ($fixed[$fixlinenr] =~
- s/(^\+.*) {8,8}\t/$1\t\t/) {}
+ s/(^\+.*) {$tabsize,$tabsize}\t/$1\t\t/) {}
while ($fixed[$fixlinenr] =~
s/(^\+.*) +\t/$1\t/) {}
}
@@ -3194,11 +3197,11 @@ sub process {
if ($perl_version_ok &&
$sline =~ /^\+\t+( +)(?:$c90_Keywords\b|\{\s*$|\}\s*(?:else\b|while\b|\s*$)|$Declare\s*$Ident\s*[;=])/) {
my $indent = length($1);
- if ($indent % 8) {
+ if ($indent % $tabsize) {
if (WARN("TABSTOP",
"Statements should start on a tabstop\n" . $herecurr) &&
$fix) {
- $fixed[$fixlinenr] =~ s@(^\+\t+) +@$1 . "\t" x ($indent/8)@e;
+ $fixed[$fixlinenr] =~ s@(^\+\t+) +@$1 . "\t" x ($indent/$tabsize)@e;
}
}
}
@@ -3216,8 +3219,8 @@ sub process {
my $newindent = $2;

my $goodtabindent = $oldindent .
- "\t" x ($pos / 8) .
- " " x ($pos % 8);
+ "\t" x ($pos / $tabsize) .
+ " " x ($pos % $tabsize);
my $goodspaceindent = $oldindent . " " x $pos;

if ($newindent ne $goodtabindent &&
@@ -3688,11 +3691,11 @@ sub process {
#print "line<$line> prevline<$prevline> indent<$indent> sindent<$sindent> check<$check> continuation<$continuation> s<$s> cond_lines<$cond_lines> stat_real<$stat_real> stat<$stat>\n";

if ($check && $s ne '' &&
- (($sindent % 8) != 0 ||
+ (($sindent % $tabsize) != 0 ||
($sindent < $indent) ||
($sindent == $indent &&
($s !~ /^\s*(?:\}|\{|else\b)/)) ||
- ($sindent > $indent + 8))) {
+ ($sindent > $indent + $tabsize))) {
WARN("SUSPECT_CODE_INDENT",
"suspect code indent for conditional statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n");
}
--
2.21.0