[PATCH] update checkpatch.pl to version 0.10

Andy Whitcroft
2007-09-12T15:01:30Z

This version brings a number of new checks, and a number of bug
fixes. Of note:

- better categorisation and space checks for dual use unary/binary
operators
- warn on deprecated use of {SPIN,RW}_LOCK_UNLOCKED
- check if/for/while with trailing ';' for hanging statements
- detect DOS line endings
- detect redundant casts for kalloc()

Andy Whitcroft (18):
Version: 0.10
asmlinkage is also a storage type
pull out inline specifiers
allow only some operators before a unary operator
parenthesised values may span line ends
add additional attribute matching
handle sparse annotations within pointer type space checks
support alternative function definition syntax for typedefs
check if/for/while with trailing ';' for hanging statements
fix output format for case checks
deprecate SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED
allow complex macros with bracketing braces
detect and report DOS line endings
fastcall is a valid function attribute
bracket spacing is ok for 'for'
categorise operators into unary/binary/definitions
add heuristic to pick up on unannotated types
remove spurious warnings from cat_vet

Dave Jones (1):
Make checkpatch warn about pointless casting of kalloc returns.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
---
scripts/checkpatch.pl | 254 +++++++++++++++++++++++++++++++++++++-----------
1 files changed, 196 insertions(+), 58 deletions(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index dae7d30..59ad83c 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -9,7 +9,7 @@ use strict;
my $P = $0;
$P =~ s@.*/@@g;

-my $V = '0.09';
+my $V = '0.10';

use Getopt::Long qw(:config no_auto_abbrev);

@@ -212,6 +212,11 @@ sub ctx_block_level {

return ctx_block_get($linenr, $remain, 0, '{', '}', 0);
}
+sub ctx_statement_level {
+ my ($linenr, $remain, $off) = @_;
+
+ return ctx_block_get($linenr, $remain, 0, '(', ')', $off);
+}

sub ctx_locate_comment {
my ($first_line, $end_line) = @_;
@@ -255,13 +260,42 @@ sub ctx_has_comment {
return ($cmt ne '');
}

+sub ctx_expr_before {
+ my ($line) = @_;
+
+ ##print "CHECK<$line>\n";
+
+ my $pos = length($line) - 1;
+ my $count = 0;
+ my $c;
+
+ for (; $pos >= 0; $pos--) {
+ $c = substr($line, $pos, 1);
+ ##print "CHECK: c<$c> count<$count>\n";
+ if ($c eq ')') {
+ $count++;
+ } elsif ($c eq '(') {
+ last if (--$count == 0);
+ }
+ }
+
+ ##print "CHECK: result<" . substr($line, 0, $pos) . ">\n";
+
+ return substr($line, 0, $pos);
+}
+
sub cat_vet {
my ($vet) = @_;
+ my ($res, $coded);

- $vet =~ s/\t/^I/;
- $vet =~ s/$/\$/;
+ $res = '';
+ while ($vet =~ /([^[:cntrl:]]*)([[:cntrl:]])/g) {
+ $coded = sprintf("^%c", unpack('C', $2) + 64);
+ $res .= $1 . $coded;
+ }
+ $res =~ s/$/\$/;

- return $vet;
+ return $res;
}

my @report = ();
@@ -310,8 +344,17 @@ sub process {
my $first_line = 0;

my $Ident = qr{[A-Za-z\d_]+};
- my $Storage = qr{extern|static};
- my $Sparse = qr{__user|__kernel|__force|__iomem|__must_check|__init_refok};
+ my $Storage = qr{extern|static|asmlinkage};
+ my $Sparse = qr{
+ __user|
+ __kernel|
+ __force|
+ __iomem|
+ __must_check|
+ __init_refok|
+ fastcall
+ }x;
+ my $Inline = qr{inline|__always_inline|noinline};
my $NonptrType = qr{
\b
(?:const\s+)?
@@ -345,11 +388,18 @@ sub process {
(?:\s+$Sparse)*
}x;
my $Declare = qr{(?:$Storage\s+)?$Type};
- my $Attribute = qr{const|__read_mostly|__init|__initdata|__meminit};
-
+ my $Attribute = qr{
+ const|
+ __read_mostly|
+ __(?:mem|cpu|dev|)(?:initdata|init)
+ }x;
my $Member = qr{->$Ident|\.$Ident|\[[^]]*\]};
my $Lval = qr{$Ident(?:$Member)*};

+ # Possible bare types.
+ my @bare = ();
+ my $Bare = $NonptrType;
+
# Pre-scan the patch looking for any __setup documentation.
my @setup_docs = ();
my $setup_docs = 0;
@@ -477,7 +527,11 @@ sub process {
next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);

#trailing whitespace
- if ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
+ if ($line =~ /^\+.*\015/) {
+ my $herevet = "$here\n" . cat_vet($line) . "\n";
+ ERROR("DOS line endings\n" . $herevet);
+
+ } elsif ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
my $herevet = "$here\n" . cat_vet($line) . "\n";
ERROR("trailing whitespace\n" . $herevet);
}
@@ -509,6 +563,30 @@ sub process {
# Standardise the strings and chars within the input to simplify matching.
$line = sanitise_line($line);

+# Check for potential 'bare' types
+ if ($realcnt &&
+ $line !~ /^.\s*(?:$Storage\s+)?(?:$Inline\s+)?$Type\b/ &&
+ $line !~ /$Ident:\s*$/ &&
+ $line !~ /^.\s*$Ident\s*\(/ &&
+ ($line =~ /^.(?:$Storage\s+)?(?:$Inline\s+)?($Ident)\b/ ||
+ $line =~ /^.\s*(?:$Storage\s+)?($Ident)\b\s*\**\s*$Ident\s*(?:;|=)/)) {
+ my $possible = $1;
+ if ($possible !~ /^(?:$Storage|$Type|DEFINE_\S+)$/ &&
+ $possible ne 'goto' && $possible ne 'return' &&
+ $possible ne 'struct' && $possible ne 'enum' &&
+ $possible ne 'case' && $possible ne 'else' &&
+ $possible ne 'typedef') {
+ #print "POSSIBLE<$possible>\n";
+ push(@bare, $possible);
+ my $bare = join("|", @bare);
+ $Bare = qr{
+ \b(?:$bare)\b
+ (?:\s*\*+\s*const|\s*\*+|(?:\s*\[\s*\])+)?
+ (?:\s+$Sparse)*
+ }x;
+ }
+ }
+
#
# Checks which may be anchored in the context.
#
@@ -531,18 +609,19 @@ sub process {
}
}
if ($err ne '') {
- ERROR("switch and case should be at the same indent\n$hereline\n$err\n");
+ ERROR("switch and case should be at the same indent\n$hereline$err");
}
}

# 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 ($line =~ /\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.#/) {
- my @ctx = ctx_statement($linenr, $realcnt, 0);
+ my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, 0);
my $ctx_ln = $linenr + $#ctx + 1;
my $ctx_cnt = $realcnt - $#ctx - 1;
my $ctx = join("\n", @ctx);

+ # Skip over any removed lines in the context following statement.
while ($ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^-/) {
$ctx_ln++;
$ctx_cnt--;
@@ -553,6 +632,13 @@ sub process {
ERROR("That open brace { should be on the previous line\n" .
"$here\n$ctx\n$lines[$ctx_ln - 1]");
}
+ if ($level == 0 && $ctx =~ /\)\s*\;\s*$/ && defined $lines[$ctx_ln - 1]) {
+ my ($nlength, $nindent) = line_stats($lines[$ctx_ln - 1]);
+ if ($nindent > $indent) {
+ WARN("Trailing semicolon indicates no statements, indent implies otherwise\n" .
+ "$here\n$ctx\n$lines[$ctx_ln - 1]");
+ }
+ }
}

#ignore lines not being added
@@ -619,7 +705,7 @@ sub process {
# check for new typedefs, only function parameters and sparse annotations
# make sense.
if ($line =~ /\btypedef\s/ &&
- $line !~ /\btypedef\s+$Type\s+\(\s*\*$Ident\s*\)\s*\(/ &&
+ $line !~ /\btypedef\s+$Type\s+\(\s*\*?$Ident\s*\)\s*\(/ &&
$line !~ /\b__bitwise(?:__|)\b/) {
WARN("do not add new typedefs\n" . $herecurr);
}
@@ -633,11 +719,11 @@ sub process {
ERROR("\"(foo $1 )\" should be \"(foo $1)\"\n" .
$herecurr);

- } elsif ($line =~ m{$NonptrType(\*+)(?:\s+$Attribute)?\s+[A-Za-z\d_]+}) {
+ } elsif ($line =~ m{$NonptrType(\*+)(?:\s+(?:$Attribute|$Sparse))?\s+[A-Za-z\d_]+}) {
ERROR("\"foo$1 bar\" should be \"foo $1bar\"\n" .
$herecurr);

- } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+$Attribute)\s+[A-Za-z\d_]+}) {
+ } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+(?:$Attribute|$Sparse))\s+[A-Za-z\d_]+}) {
ERROR("\"foo $1 bar\" should be \"foo $1bar\"\n" .
$herecurr);
}
@@ -693,7 +779,13 @@ sub process {
$opline = expand_tabs($opline);
$opline =~ s/^./ /;
if (!($line=~/\#\s*include/)) {
- my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|=>|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
+ my $ops = qr{
+ <<=|>>=|<=|>=|==|!=|
+ \+=|-=|\*=|\/=|%=|\^=|\|=|&=|
+ =>|->|<<|>>|<|>|=|!|~|
+ &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/
+ }x;
+ my @elements = split(/($ops|;)/, $opline);
my $off = 0;
for (my $n = 0; $n < $#elements; $n += 2) {
$off += length($elements[$n]);
@@ -733,7 +825,60 @@ sub process {
my $ptr = (" " x $off) . "^";
my $hereptr = "$hereline$ptr\n";

- ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
+ # Classify operators into binary, unary, or
+ # definitions (* only) where they have more
+ # than one mode.
+ my $unary_ctx = $prevline . $ca;
+ $unary_ctx =~ s/^./ /;
+ my $is_unary = 0;
+ my $Unary = qr{
+ (?:
+ ^|;|,|$ops|\(|\?|:|
+ \(\s*$Type\s*\)|
+ $Type|
+ return|case|else|
+ \{|\}|
+ \[|
+ ^.\#\s*define\s+$Ident\s*(?:\([^\)]*\))?|
+ ^.\#\s*else|
+ ^.\#\s*endif|
+ ^.\#\s*(?:if|ifndef|ifdef)\b.*
+ )\s*(?:|\\)\s*$
+ }x;
+ my $UnaryFalse = qr{
+ sizeof\s*\(\s*$Type\s*\)\s*$
+ }x;
+ my $UnaryDefine = qr{
+ (?:$Type|$Bare)\s*|
+ (?:$Type|$Bare).*,\s*\**
+ }x;
+ if ($op eq '-' || $op eq '&' || $op eq '*') {
+ # An operator is binary if the left hand
+ # side is a value. Pick out the known
+ # non-values.
+ if ($unary_ctx =~ /$Unary$/s &&
+ $unary_ctx !~ /$UnaryFalse$/s) {
+ $is_unary = 1;
+
+ # Special handling for ')' check if this
+ # brace represents a conditional, if so
+ # we are unary.
+ } elsif ($unary_ctx =~ /\)\s*$/) {
+ my $before = ctx_expr_before($unary_ctx);
+ if ($before =~ /(?:for|if|while)\s*$/) {
+ $is_unary = 1;
+ }
+ }
+
+ # Check for type definition for of '*'.
+ if ($op eq '*' && $unary_ctx =~ /$UnaryDefine$/) {
+ $is_unary = 2;
+ }
+ }
+
+ #if ($op eq '-' || $op eq '&' || $op eq '*') {
+ # print "UNARY: <$is_unary $a:$op:$c> <$ca:$op:$cc> <$unary_ctx>\n";
+ #}

# ; should have either the end of line or a space or \ after it
if ($op eq ';') {
@@ -757,9 +902,16 @@ sub process {
ERROR("need space after that '$op' $at\n" . $hereptr);
}

- # unary ! and unary ~ are allowed no space on the right
- } elsif ($op eq '!' or $op eq '~') {
- if ($ctx !~ /[WOEB]x./) {
+ # '*' as part of a type definition -- reported already.
+ } elsif ($op eq '*' && $is_unary == 2) {
+ #warn "'*' is part of type\n";
+
+ # unary operators should have a space before and
+ # none after. May be left adjacent to another
+ # unary operator, or a cast
+ } elsif ($op eq '!' || $op eq '~' ||
+ ($is_unary && ($op eq '*' || $op eq '-' || $op eq '&'))) {
+ if ($ctx !~ /[WEB]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
ERROR("need space before that '$op' $at\n" . $hereptr);
}
if ($ctx =~ /.xW/) {
@@ -775,39 +927,13 @@ sub process {
ERROR("no space before that '$op' $at\n" . $hereptr);
}

- # & 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
- #
- } elsif ($op eq '&' or $op eq '-') {
- if ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]/) {
- ERROR("need space before that '$op' $at\n" . $hereptr);
- }
-
- # * is the same as & only adding:
- # type:
- # (foo *)
- # (foo **)
- #
- } elsif ($op eq '*') {
- if ($ca !~ /$Type$/ && $cb !~ /(\*$;|$;\*)/ &&
- $ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]|OxV|WxB|BxB/) {
- ERROR("need space before that '$op' $at\n" . $hereptr);
- }
-
# << and >> may either have or not have spaces both sides
- } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
- $op eq '^' or $op eq '|')
+ } elsif ($op eq '<<' or $op eq '>>' or
+ $op eq '&' or $op eq '^' or $op eq '|' or
+ $op eq '+' or $op eq '-' or
+ $op eq '*' or $op eq '/')
{
- if ($ctx !~ /VxV|WxW|VxE|WxE/) {
+ if ($ctx !~ /VxV|WxW|VxE|WxE|VxO/) {
ERROR("need consistent spacing around '$op' $at\n" .
$hereptr);
}
@@ -865,10 +991,12 @@ sub process {
}

# check spacing on paretheses
- if ($line =~ /\(\s/ && $line !~ /\(\s*$/) {
+ if ($line =~ /\(\s/ && $line !~ /\(\s*(?:\\)?$/ &&
+ $line !~ /for\s*\(\s+;/) {
ERROR("no space after that open parenthesis '('\n" . $herecurr);
}
- if ($line =~ /\s\)/) {
+ if ($line =~ /\s\)/ && $line !~ /^.\s*\)/ &&
+ $line !~ /for\s*\(.*;\s+\)/) {
ERROR("no space before that close parenthesis ')'\n" . $herecurr);
}

@@ -926,10 +1054,10 @@ sub process {
# multi-statement macros should be enclosed in a do while loop, grab the
# first statement and ensure its the whole macro if its not enclosed
# in a known goot container
- if (($prevline=~/\#define.*\\/) and
- !($prevline=~/do\s+{/) and !($prevline=~/\(\{/) and
- !($line=~/do.*{/) and !($line=~/\(\{/) and
- !($line=~/^.\s*$Declare\s/)) {
+ if ($prevline =~ /\#define.*\\/ &&
+ $prevline !~/(?:do\s+{|\(\{|\{)/ &&
+ $line !~ /(?:do\s+{|\(\{|\{)/ &&
+ $line !~ /^.\s*$Declare\s/) {
# Grab the first statement, if that is the entire macro
# its ok. This may start either on the #define line
# or the one below.
@@ -1027,6 +1155,11 @@ sub process {
WARN("Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr);
}

+# SPIN_LOCK_UNLOCKED & RW_LOCK_UNLOCKED are deprecated
+ if ($line =~ /\b(SPIN_LOCK_UNLOCKED|RW_LOCK_UNLOCKED)/) {
+ ERROR("Use of $1 is deprecated: see Documentation/spinlocks.txt\n" . $herecurr);
+ }
+
# warn about #if 0
if ($line =~ /^.#\s*if\s+0\b/) {
CHK("if this code is redundant consider removing it\n" .
@@ -1073,8 +1206,8 @@ sub process {

# check the location of the inline attribute, that it is between
# storage class and type.
- if ($line =~ /$Type\s+(?:inline|__always_inline|noinline)\b/ ||
- $line =~ /\b(?:inline|__always_inline|noinline)\s+$Storage/) {
+ if ($line =~ /\b$Type\s+$Inline\b/ ||
+ $line =~ /\b$Inline\s+$Storage\b/) {
ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
}

@@ -1091,6 +1224,11 @@ sub process {
CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
}
}
+
+# check for pointless casting of kmalloc return
+ if ($line =~ /\*\s*\)\s*k[czm]alloc\b/) {
+ WARN("unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
+ }
}

if ($chk_patch && !$is_patch) {