checkpatch: add test for keywords not starting on tabstops

It's somewhat common and in general a defect for c90 keywords to
not start on a tabstop.

Add a test for this condition and warn when it occurs.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e3d9c34..6c1213c 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2755,6 +2755,19 @@ sub process {
                            "Logical continuations should be on the previous line\n" . $hereprev);
                }
 
+# check indentation starts on a tab stop
+               if ($^V && $^V ge 5.10.0 &&
+                   $sline =~ /^\+\t+( +)(?:$c90_Keywords\b|\{\s*$|\}\s*(?:else\b|while\b|\s*$))/) {
+                       my $indent = length($1);
+                       if ($indent % 8) {
+                               if (WARN("TABSTOP",
+                                        "Statements should start on a tabstop\n" . $herecurr) &&
+                                   $fix) {
+                                       $fixed[$fixlinenr] =~ s@(^\+\t+) +@$1 . "\t" x ($indent/8)@e;
+                               }
+                       }
+               }
+
 # check multi-line statement indentation matches previous line
                if ($^V && $^V ge 5.10.0 &&
                    $prevline =~ /^\+([ \t]*)((?:$c90_Keywords(?:\s+if)\s*)|(?:$Declare\s*)?(?:$Ident|\(\s*\*\s*$Ident\s*\))\s*|$Ident\s*=\s*$Ident\s*)\(.*(\&\&|\|\||,)\s*$/) {