From 218906df66987ff0664dff986996be3df4bbde24 Mon Sep 17 00:00:00 2001 From: Julius Werner Date: Thu, 25 Mar 2021 21:12:49 -0700 Subject: lint: checkpatch: Add SUSPICIOUS_CODE_INDENT test This patch adds a new test to checkpatch that identifies cases where a line after a conditional statement is incorrectly intended (possibly indicating the mistake of forgetting to add braces), like this: if (a) b; c; Unfortunately, it seems like checkpatch is partially unmaintained in upstream Linux at the moment with maintainers either not responding at all or not even willing to look at new patches [1]. Since detecting this error class is important to coreboot, let's just carry this feature locally for now. [1] https://lkml.org/lkml/2021/4/15/1488 Signed-off-by: Julius Werner Change-Id: I7bb90b56dfc7582271d2b82cb42a2c1df477054f Reviewed-on: https://review.coreboot.org/c/coreboot/+/51838 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Angel Pons Reviewed-by: Nico Huber --- util/lint/checkpatch.pl | 66 +++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 56 insertions(+), 10 deletions(-) diff --git a/util/lint/checkpatch.pl b/util/lint/checkpatch.pl index 1affdb7b33..f1c31c54c0 100755 --- a/util/lint/checkpatch.pl +++ b/util/lint/checkpatch.pl @@ -1197,8 +1197,12 @@ sub copy_spacing { sub line_stats { my ($line) = @_; - # Drop the diff line leader and expand tabs + # Drop the diff line leader $line =~ s/^.//; + + # Treat labels like whitespace when counting indentation + $line =~ s/^( ?$Ident:)/" " x length($1)/e; + $line = expand_tabs($line); # Pick the indent from the front of the line. @@ -1331,15 +1335,13 @@ sub ctx_statement_block { my $type = ''; my $level = 0; - my @stack = (); + my @stack = (['', $level]); my $p; my $c; my $len = 0; my $remainder; while (1) { - @stack = (['', 0]) if ($#stack == -1); - #warn "CSB: blk<$blk> remain<$remain>\n"; # If we are about to drop off the end, pull in more # context. @@ -1373,9 +1375,9 @@ sub ctx_statement_block { # Handle nested #if/#else. if ($remainder =~ /^#\s*(?:ifndef|ifdef|if)\s/) { push(@stack, [ $type, $level ]); - } elsif ($remainder =~ /^#\s*(?:else|elif)\b/) { - ($type, $level) = @{$stack[$#stack - 1]}; - } elsif ($remainder =~ /^#\s*endif\b/) { + } elsif ($remainder =~ /^#\s*(?:else|elif)\b/ && $#stack > 0) { + ($type, $level) = @{$stack[$#stack]}; + } elsif ($remainder =~ /^#\s*endif\b/ && $#stack > 0) { ($type, $level) = @{pop(@stack)}; } @@ -1545,9 +1547,9 @@ sub ctx_block_get { # Handle nested #if/#else. if ($lines[$line] =~ /^.\s*#\s*(?:ifndef|ifdef|if)\s/) { push(@stack, $level); - } elsif ($lines[$line] =~ /^.\s*#\s*(?:else|elif)\b/) { - $level = $stack[$#stack - 1]; - } elsif ($lines[$line] =~ /^.\s*#\s*endif\b/) { + } elsif ($lines[$line] =~ /^.\s*#\s*(?:else|elif)\b/ && $#stack > 0) { + $level = $stack[$#stack]; + } elsif ($lines[$line] =~ /^.\s*#\s*endif\b/ && $#stack > 0) { $level = pop(@stack); } @@ -3615,6 +3617,50 @@ sub process { WARN("SUSPECT_CODE_INDENT", "suspect code indent for conditional statements ($indent, $sindent)\n" . $herecurr . "$stat_real\n"); } + +# Also check if the next statement after the previous condition has the same indent + my ($stat_next, undef, $line_nr_next_next) = + ctx_statement_block($line_nr_next, $remain_next, $off_next); + my $s_next = $stat_next; + + # Remove line prefixes + $s_next =~ s/\n./\n/g; + + # Remove any comments + $s_next =~ s/$;//g; + + # Remove any leading labels + $s_next =~ s/\n( ?$Ident:)/"\n" . " " x length($1)/eg; + + # Skip this check for in case next statement starts with 'else' + if ($s_next !~ /\belse\b/) { + + # Remove while that belongs to a do {} while + if ($stat =~ /\bdo\b/) { + $s_next =~ s/^.*\bwhile\b\s*($balanced_parens)\s*?//; + } + + # Remove blank lines + $s_next =~ s/\s*\\?\n//g; + + # Get the real next lines + my $next_nof_lines = $line_nr_next_next - $line_nr_next; + my $stat_next_real = raw_line($line_nr_next, $next_nof_lines); + if (!defined($stat_next_real)) { + $stat_next_real = ""; + } elsif ($next_nof_lines > 1) { + $stat_next_real = "[...]\n$stat_next_real"; + } + my (undef, $nindent) = line_stats('+' . $s_next); + + #print "stat_next<$stat_next> stat<$stat> indent<$indent> nindent<$nindent> s_next<$s_next> stat_next_real<$stat_next_real>\n"; + + if ($nindent > $indent) { + WARN("SUSPICIOUS_CODE_INDENT", + "suspicious code indentation after conditional statements\n" . + $herecurr . "$stat_real\n$stat_next_real\n"); + } + } } # Track the 'values' across context and added lines. -- cgit v1.2.3