linux/scripts/checkpatch.pl

596 lines
15 KiB
Perl

#!/usr/bin/perl -w
# (c) 2001, Dave Jones. <davej@codemonkey.org.uk> (the file handling bit)
# (c) 2005, Joel Scohpp <jschopp@austin.ibm.com> (the ugly bit)
# (c) 2007, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite, etc)
# Licensed under the terms of the GNU GPL License version 2
use strict;
my $P = $0;
my $V = '0.01';
use Getopt::Long qw(:config no_auto_abbrev);
my $quiet = 0;
my $tree = 1;
my $chk_signoff = 1;
my $chk_patch = 1;
GetOptions(
'q|quiet' => \$quiet,
'tree!' => \$tree,
'signoff!' => \$chk_signoff,
'patch!' => \$chk_patch,
) or exit;
my $exit = 0;
if ($#ARGV < 0) {
print "usage: patchstylecheckemail.pl [options] patchfile\n";
print "version: $V\n";
print "options: -q => quiet\n";
print " --no-tree => run without a kernel tree\n";
exit(1);
}
if ($tree && !top_of_kernel_tree()) {
print "Must be run from the top-level dir. of a kernel tree\n";
exit(2);
}
my @deprecated = ();
my $removal = 'Documentation/feature-removal-schedule.txt';
if ($tree && -f $removal) {
open(REMOVE, "<$removal") || die "$P: $removal: open failed - $!\n";
while (<REMOVE>) {
if (/^Files:\s+(.*\S)/) {
for my $file (split(/[, ]+/, $1)) {
if ($file =~ m@include/(.*)@) {
push(@deprecated, $1);
}
}
}
}
}
my @lines = ();
while (<>) {
chomp;
push(@lines, $_);
if (eof(ARGV)) {
if (!process($ARGV, @lines)) {
$exit = 1;
}
@lines = ();
}
}
exit($exit);
sub top_of_kernel_tree {
if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
(-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
(-d "Documentation") && (-d "arch") && (-d "include") &&
(-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
(-d "kernel") && (-d "lib") && (-d "scripts")) {
return 1;
}
return 0;
}
sub expand_tabs {
my ($str) = @_;
my $res = '';
my $n = 0;
for my $c (split(//, $str)) {
if ($c eq "\t") {
$res .= ' ';
$n++;
for (; ($n % 8) != 0; $n++) {
$res .= ' ';
}
next;
}
$res .= $c;
$n++;
}
return $res;
}
sub cat_vet {
my ($vet) = @_;
$vet =~ s/\t/^I/;
$vet =~ s/$/\$/;
return $vet;
}
sub process {
my $filename = shift;
my @lines = @_;
my $linenr=0;
my $prevline="";
my $stashline="";
my $lineforcounting='';
my $indent;
my $previndent=0;
my $stashindent=0;
my $clean = 1;
my $signoff = 0;
my $is_patch = 0;
# Trace the real file/line as we go.
my $realfile = '';
my $realline = 0;
my $realcnt = 0;
my $here = '';
my $in_comment = 0;
my $first_line = 0;
foreach my $line (@lines) {
$linenr++;
#extract the filename as it passes
if ($line=~/^\+\+\+\s+(\S+)/) {
$realfile=$1;
$in_comment = 0;
next;
}
#extract the line range in the file after the patch is applied
if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
$is_patch = 1;
$first_line = 1;
$in_comment = 0;
$realline=$1-1;
if (defined $2) {
$realcnt=$3+1;
} else {
$realcnt=1+1;
}
next;
}
#track the line number as we move through the hunk
if ($line=~/^[ \+]/) {
$realline++;
$realcnt-- if ($realcnt != 0);
# track any sort of multi-line comment. Obviously if
# the added text or context do not include the whole
# comment we will not see it. Such is life.
#
# Guestimate if this is a continuing comment. If this
# is the start of a diff block and this line starts
# ' *' then it is very likely a comment.
if ($first_line and $line =~ m@^.\s*\*@) {
$in_comment = 1;
}
if ($line =~ m@/\*@) {
$in_comment = 1;
}
if ($line =~ m@\*/@) {
$in_comment = 0;
}
$lineforcounting = $line;
$lineforcounting =~ s/^\+//;
$lineforcounting = expand_tabs($lineforcounting);
my ($white) = ($lineforcounting =~ /^(\s*)/);
$indent = length($white);
# Track the previous line.
($prevline, $stashline) = ($stashline, $line);
($previndent, $stashindent) = ($stashindent, $indent);
$first_line = 0;
}
#make up the handle for any error we report on this line
$here = "PATCH: $ARGV:$linenr:";
$here .= "\nFILE: $realfile:$realline:" if ($realcnt != 0);
my $herecurr = "$here\n$line\n\n";
my $hereprev = "$here\n$prevline\n$line\n\n";
#check the patch for a signoff:
if ($line =~ /^\s*Signed-off-by:\s/) {
$signoff++;
} elsif ($line =~ /^\s*signed-off-by:/i) {
if (!($line =~ /^\s*Signed-off-by:/)) {
print "use Signed-off-by:\n";
print "$herecurr";
$clean = 0;
}
if ($line =~ /^\s*signed-off-by:\S/i) {
print "need space after Signed-off-by:\n";
print "$herecurr";
$clean = 0;
}
}
#ignore lines not being added
if ($line=~/^[^\+]/) {next;}
# check we are in a valid source file *.[hcsS] if not then ignore this hunk
next if ($realfile !~ /\.[hcsS]$/);
#trailing whitespace
if ($line=~/\S\s+$/) {
my $herevet = "$here\n" . cat_vet($line) . "\n\n";
print "trailing whitespace\n";
print "$herevet";
$clean = 0;
}
#80 column limit
if (!($prevline=~/\/\*\*/) && length($lineforcounting) > 80) {
print "line over 80 characters\n";
print "$herecurr";
$clean = 0;
}
# check we are in a valid source file *.[hc] if not then ignore this hunk
next if ($realfile !~ /\.[hc]$/);
# at the beginning of a line any tabs must come first and anything
# more than 8 must use tabs.
if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s* \s*/) {
my $herevet = "$here\n" . cat_vet($line) . "\n\n";
print "use tabs not spaces\n";
print "$herevet";
$clean = 0;
}
#
# The rest of our checks refer specifically to C style
# only apply those _outside_ comments.
#
next if ($in_comment);
# no C99 // comments
if ($line =~ m@//@ and !($line =~ m@\".*//.*\"@)) {
print "do not use C99 // comments\n";
print "$herecurr";
$clean = 0;
}
# Remove comments from the line before processing.
$line =~ s@/\*.*\*/@@g;
$line =~ s@/\*.*@@;
$line =~ s@.*\*/@@;
$line =~ s@//.*@@;
#EXPORT_SYMBOL should immediately follow its function closing }.
if (($line =~ /EXPORT_SYMBOL.*\(.*\)/) ||
($line =~ /EXPORT_UNUSED_SYMBOL.*\(.*\)/)) {
if (($prevline !~ /^}/) &&
($prevline !~ /^\+}/) &&
($prevline !~ /^ }/)) {
print "EXPORT_SYMBOL(func); should immediately follow its function\n";
print "$herecurr";
$clean = 0;
}
}
# check for static initialisers.
if ($line=~/\s*static\s.*=\s+(0|NULL);/) {
print "do not initialise statics to 0 or NULL\n";
print "$herecurr";
$clean = 0;
}
# check for new typedefs.
if ($line=~/\s*typedef\s/) {
print "do not add new typedefs\n";
print "$herecurr";
$clean = 0;
}
# * goes on variable not on type
if ($line=~/[A-Za-z\d_]+\* [A-Za-z\d_]+/) {
print "\"foo* bar\" should be \"foo *bar\"\n";
print "$herecurr";
$clean = 0;
}
# # no BUG() or BUG_ON()
# if ($line =~ /\b(BUG|BUG_ON)\b/) {
# print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
# print "$herecurr";
# $clean = 0;
# }
# printk should use KERN_* levels
if ($line =~ /\bprintk\((?!KERN_)/) {
print "printk() should include KERN_ facility level\n";
print "$herecurr";
$clean = 0;
}
#function brace can't be on same line, except for #defines of do while, or if closed on same line
if (($line=~/[A-Za-z\d_]+\**\s+\**[A-Za-z\d_]+\(.*\).* {/) and
!($line=~/\#define.*do\s{/) and !($line=~/}/)) {
print "braces following function declarations go on the next line\n";
print "$herecurr";
$clean = 0;
}
my $opline = $line;
$opline =~ s/^.//;
if (!($line=~/\#\s*include/)) {
# Check operator spacing.
my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
for (my $n = 0; $n < $#elements; $n += 2) {
# $wN says we have white-space before or after
# $sN says we have a separator before or after
# $oN says we have another operator before or after
my $w1 = $elements[$n] =~ /\s$/;
my $s1 = $elements[$n] =~ /(\[|\(|\s)$/;
my $o1 = $elements[$n] eq '';
my $op = $elements[$n + 1];
my $w2 = 1;
my $s2 = 1;
my $o2 = 0;
# If we have something after the operator handle it.
if (defined $elements[$n + 2]) {
$w2 = $elements[$n + 2] =~ /^\s/;
$s2 = $elements[$n + 2] =~ /^(\s|\)|\]|;)/;
$o2 = $elements[$n + 2] eq '';
}
# Generate the context.
my $at = "here: ";
for (my $m = $n; $m >= 0; $m--) {
if ($elements[$m] ne '') {
$at .= $elements[$m];
last;
}
}
$at .= $op;
for (my $m = $n + 2; defined $elements[$m]; $m++) {
if ($elements[$m] ne '') {
$at .= $elements[$m];
last;
}
}
##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
# Skip things apparently in quotes.
next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
# We need ; as an operator. // is a comment.
if ($op eq ';' or $op eq '//') {
# -> should have no spaces
} elsif ($op eq '->') {
if ($s1 or $s2) {
print "no spaces around that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# , must have a space on the right.
} elsif ($op eq ',') {
if (!$s2) {
print "need space after that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# unary ! and unary ~ are allowed no space on the right
} elsif ($op eq '!' or $op eq '~') {
if (!$s1 && !$o1) {
print "need space before that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
if ($s2) {
print "no space after that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# unary ++ and unary -- are allowed no space on one side.
} elsif ($op eq '++' or $op eq '--') {
if (($s1 && $s2) || ((!$s1 && !$o1) && (!$s2 && !$o2))) {
print "need space one side of that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# & is both unary and binary
# unary:
# a &b
# binary (consistent spacing):
# a&b OK
# a & b OK
#
# boiling down to: if there is a space on the right then there
# should be one on the left.
#
# - is the same
#
# * is the same only adding:
# type:
# (foo *)
# (foo **)
#
} elsif ($op eq '&' or $op eq '-' or $op eq '*') {
if ($w2 and !$w1) {
print "need space before that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# << and >> may either have or not have spaces both sides
} elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
$op eq '^' or $op eq '|')
{
if ($s1 != $s2) {
print "need consistent spacing around '$op' $at\n";
print "$herecurr";
$clean = 0;
}
# All the others need spaces both sides.
} elsif (!$s1 or !$s2) {
print "need spaces around that '$op' $at\n";
print "$herecurr";
$clean = 0;
}
}
}
#need space before brace following if, while, etc
if ($line=~/\(.*\){/) {
print "need a space before the brace\n";
print "$herecurr";
$clean = 0;
}
#goto labels aren't indented, allow a single space however
if ($line=~/^.\s+[A-Za-z\d_]+:/ and
!($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
print "labels should not be indented\n";
print "$herecurr";
$clean = 0;
}
# Need a space before open parenthesis after if, while etc
if ($line=~/(if|while|for|switch)\(/) {
print "need a space before the open parenthesis\n";
print "$herecurr";
$clean = 0;
}
# Check for illegal assignment in if conditional.
if ($line=~/(if|while)\s*\(.*[^<>!=]=[^=].*\)/) {
print "do not use assignment in if condition\n";
print "$herecurr";
$clean = 0;
}
# Check for }<nl>else {, these must be at the same
# indent level to be relevant to each other.
if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
$previndent == $indent) {
print "else should follow close brace\n";
print "$hereprev";
$clean = 0;
}
# Check for switch () {<nl>case, these must be at the
# same indent. We will only catch the first one, as our
# context is very small but people tend to be consistent
# so we will catch them out more often than not.
if ($prevline=~/\s*switch\s*\(.*\)/ and $line=~/\s*case\s+/
and $previndent != $indent) {
print "switch and case should be at the same indent\n";
print "$hereprev";
$clean = 0;
}
#studly caps, commented out until figure out how to distinguish between use of existing and adding new
# if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
# print "No studly caps, use _\n";
# print "$herecurr";
# $clean = 0;
# }
#no spaces allowed after \ in define
if ($line=~/\#define.*\\\s$/) {
print("Whitepspace after \\ makes next lines useless\n");
print "$herecurr";
$clean = 0;
}
#warn if <asm/foo.h> is #included and <linux/foo.h> is available.
if ($tree && $line =~ qr|\s*\#\s*include\s*\<asm\/(.*)\.h\>|) {
my $checkfile = "include/linux/$1.h";
if (-f $checkfile) {
print "Use #include <linux/$1.h> instead of <asm/$1.h>\n";
print $herecurr;
$clean = 0;
}
}
#if/while/etc brace do not go on next line, unless #defining a do while loop, or if that brace on the next line is for something else
if ($prevline=~/(if|while|for|switch)\s*\(/) {
my @opened = $prevline=~/\(/g;
my @closed = $prevline=~/\)/g;
my $nr_line = $linenr;
my $remaining = $realcnt;
my $next_line = $line;
my $extra_lines = 0;
my $display_segment = $prevline;
while ($remaining > 0 && scalar @opened > scalar @closed) {
$prevline .= $next_line;
$display_segment .= "\n" . $next_line;
$next_line = $lines[$nr_line];
$nr_line++;
$remaining--;
@opened = $prevline=~/\(/g;
@closed = $prevline=~/\)/g;
}
if (($prevline=~/(if|while|for|switch)\s*\(.*\)\s*$/) and ($next_line=~/{/) and
!($next_line=~/(if|while|for)/) and !($next_line=~/\#define.*do.*while/)) {
print "That { should be on the previous line\n";
print "$display_segment\n$next_line\n\n";
$clean = 0;
}
}
#multiline macros should be enclosed in a do while loop
if (($prevline=~/\#define.*\\/) and !($prevline=~/do\s+{/) and
!($prevline=~/\(\{/) and ($line=~/;\s*\\/) and
!($line=~/do.*{/) and !($line=~/\(\{/)) {
print "Macros with multiple statements should be enclosed in a do - while loop\n";
print "$hereprev";
$clean = 0;
}
# don't include deprecated include files
for my $inc (@deprecated) {
if ($line =~ m@\#\s*include\s*\<$inc>@) {
print "Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n";
print "$herecurr";
$clean = 0;
}
}
# don't use kernel_thread()
if ($line =~ /\bkernel_thread\b/) {
print "Don't use kernel_thread(), use kthread(): see Documentation/feature-removal-schedule.txt\n";
print "$herecurr";
$clean = 0;
}
}
if ($chk_patch && !$is_patch) {
$clean = 0;
print "Does not appear to be a unified-diff format patch\n";
}
if ($is_patch && $chk_signoff && $signoff == 0) {
$clean = 0;
print "Missing Signed-off-by: line(s)\n";
}
if ($clean == 1 && $quiet == 0) {
print "Your patch has no obvious style problems and is ready for submission.\n"
}
if ($clean == 0 && $quiet == 0) {
print "Your patch has style problems, please review. If any of these errors\n";
print "are false positives report them to the maintainer, see\n";
print "CHECKPATCH in MAINTAINERS.\n";
}
return $clean;
}