checkpatch: add checks for question mark and colon spacing

Add checks for the question mark colon operator spacing, and also check
the other uses of colon.  Colon means a number of things:

 - it introduces the else part of the ?: operator,
 - it terminates a goto label,
 - it terminates the case value,
 - it separates the identifier from the bit size on bit fields, and
 - it is used to introduce option types in asm().

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 72 insertions, 9 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 8a3b0fd67ad7..88027f237cdf 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -689,17 +689,20 @@ sub cat_vet {
 my $av_preprocessor = 0;
 my $av_pending;
 my @av_paren_type;
+my $av_pend_colon;
 
 sub annotate_reset {
         $av_preprocessor = 0;
         $av_pending = '_';
         @av_paren_type = ('E');
+        $av_pend_colon = 'O';
 }
 
 sub annotate_values {
         my ($stream, $type) = @_;
 
         my $res;
+        my $var = '_' x length($stream);
         my $cur = $stream;
 
         print "$stream\n" if ($dbg_values > 1);
@@ -784,7 +787,12 @@ sub annotate_values {
                         $av_pending = 'N';
                         $type = 'N';
 
-                } elsif ($cur =~/^(return|case|else|goto)/o) {
+                } elsif ($cur =~/^(case)/o) {
+                        print "CASE($1)\n" if ($dbg_values > 1);
+                        $av_pend_colon = 'C';
+                        $type = 'N';
+
+                } elsif ($cur =~/^(return|else|goto)/o) {
                         print "KEYWORD($1)\n" if ($dbg_values > 1);
                         $type = 'N';
 
@@ -809,6 +817,15 @@ sub annotate_values {
                         $type = 'V';
                         $av_pending = 'V';
 
+                } elsif ($cur =~ /^($Ident\s*):/) {
+                        if ($type eq 'E') {
+                                $av_pend_colon = 'L';
+                        } elsif ($type eq 'T') {
+                                $av_pend_colon = 'B';
+                        }
+                        print "IDENT_COLON($1,$type>$av_pend_colon)\n" if ($dbg_values > 1);
+                        $type = 'V';
+
                 } elsif ($cur =~ /^($Ident|$Constant)/o) {
                         print "IDENT($1)\n" if ($dbg_values > 1);
                         $type = 'V';
@@ -820,8 +837,24 @@ sub annotate_values {
                 } elsif ($cur =~/^(;|{|})/) {
                         print "END($1)\n" if ($dbg_values > 1);
                         $type = 'E';
+                        $av_pend_colon = 'O';
+
+                } elsif ($cur =~ /^(\?)/o) {
+                        print "QUESTION($1)\n" if ($dbg_values > 1);
+                        $type = 'N';
+
+                } elsif ($cur =~ /^(:)/o) {
+                        print "COLON($1,$av_pend_colon)\n" if ($dbg_values > 1);
+
+                        substr($var, length($res), 1, $av_pend_colon);
+                        if ($av_pend_colon eq 'C' || $av_pend_colon eq 'L') {
+                                $type = 'E';
+                        } else {
+                                $type = 'N';
+                        }
+                        $av_pend_colon = 'O';
 
-                } elsif ($cur =~ /^(;|\?|:|\[)/o) {
+                } elsif ($cur =~ /^(;|\[)/o) {
                         print "CLOSE($1)\n" if ($dbg_values > 1);
                         $type = 'N';
 
@@ -840,7 +873,7 @@ sub annotate_values {
                 }
         }
 
-        return $res;
+        return ($res, $var);
 }
 
 sub possible {
@@ -1294,12 +1327,14 @@ sub process {
 
                 # Track the 'values' across context and added lines.
                 my $opline = $line; $opline =~ s/^./ /;
-                my $curr_values = annotate_values($opline . "\n", $prev_values);
+                my ($curr_values, $curr_vars) =
+                                annotate_values($opline . "\n", $prev_values);
                 $curr_values = $prev_values . $curr_values;
                 if ($dbg_values) {
                         my $outline = $opline; $outline =~ s/\t/ /g;
                         print "$linenr > .$outline\n";
                         print "$linenr > $curr_values\n";
+                        print "$linenr >  $curr_vars\n";
                 }
                 $prev_values = substr($curr_values, -1);
 
@@ -1490,7 +1525,8 @@ sub process {
                                 <<=|>>=|<=|>=|==|!=|
                                 \+=|-=|\*=|\/=|%=|\^=|\|=|&=|
                                 =>|->|<<|>>|<|>|=|!|~|
-                                &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%
+                                &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/|%|
+                                \?|:
                         }x;
                         my @elements = split(/($ops|;)/, $opline);
                         my $off = 0;
@@ -1554,6 +1590,9 @@ sub process {
                                 #       print "UNARY: <$op_left$op_type $is_unary $a:$op:$c> <$ca:$op:$cc> <$unary_ctx>\n";
                                 #}
 
+                                # Get the full operator variant.
+                                my $opv = $op . substr($curr_vars, $off, 1);
+
                                 # Ignore operators passed as parameters.
                                 if ($op_type ne 'V' &&
                                     $ca =~ /\s$/ && $cc =~ /^\s*,/) {
@@ -1571,8 +1610,10 @@ sub process {
                                 # // is a comment
                                 } elsif ($op eq '//') {
 
-                                # -> should have no spaces
-                                } elsif ($op eq '->') {
+                                # No spaces for:
+                                #   ->
+                                #   :   when part of a bitfield
+                                } elsif ($op eq '->' || $opv eq ':B') {
                                         if ($ctx =~ /Wx.|.xW/) {
                                                 ERROR("spaces prohibited around that '$op' $at\n" . $hereptr);
                                         }
@@ -1628,11 +1669,33 @@ sub process {
                                                         $hereptr);
                                         }
 
+                                # A colon needs no spaces before when it is
+                                # terminating a case value or a label.
+                                } elsif ($opv eq ':C' || $opv eq ':L') {
+                                        if ($ctx =~ /Wx./) {
+                                                ERROR("space prohibited before that '$op' $at\n" . $hereptr);
+                                        }
+
                                 # All the others need spaces both sides.
                                 } elsif ($ctx !~ /[EWC]x[CWE]/) {
+                                        my $ok = 0;
+
                                         # Ignore email addresses <foo@bar>
-                                        if (!($op eq '<' && $cb =~ /$;\S+\@\S+>/) &&
-                                            !($op eq '>' && $cb =~ /<\S+\@\S+$;/)) {
+                                        if (($op eq '<' &&
+                                             $cc =~ /^\S+\@\S+>/) ||
+                                            ($op eq '>' &&
+                                             $ca =~ /<\S+\@\S+$/))
+                                        {
+                                                $ok = 1;
+                                        }
+
+                                        # Ignore ?:
+                                        if (($opv eq ':O' && $ca =~ /\?$/) ||
+                                            ($op eq '?' && $cc =~ /^:/)) {
+                                                $ok = 1;
+                                        }
+
+                                        if ($ok == 0) {
                                                 ERROR("spaces required around that '$op' $at\n" . $hereptr);
                                         }
                                 }