checkpatch: create an EXPERIMENTAL --fix option to correct patches

Some patches have simple defects in whitespace and formatting that
checkpatch could correct automatically.  Attempt to do so.

Add a --fix option to create a "<inputfile>.EXPERIMENTAL-checkpatch-fixes"
file that tries to use normal kernel style for some of these formatting
errors.

Add warnings against using this file without verifying the changes.

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>

1 files changed, 354 insertions, 88 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index ab39ceb38286..9696be57ea42 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -27,6 +27,7 @@ my $summary = 1;
 my $mailback = 0;
 my $summary_file = 0;
 my $show_types = 0;
+my $fix = 0;
 my $root;
 my %debug;
 my %ignore_type = ();
@@ -63,6 +64,11 @@ Options:
                              is all off)
   --test-only=WORD           report only warnings/errors containing WORD
                              literally
+  --fix                      EXPERIMENTAL - may create horrible results
+                             If correctable single-line errors exist, create
+                             "<inputfile>.EXPERIMENTAL-checkpatch-fixes"
+                             with potential errors corrected to the preferred
+                             checkpatch style
   -h, --help, --version      display this help and exit
 
 When FILE is - read standard input.
@@ -114,7 +120,7 @@ GetOptions(
         'summary!'      => \$summary,
         'mailback!'     => \$mailback,
         'summary-file!' => \$summary_file,
-
+        'fix!'          => \$fix,
         'debug=s'       => \%debug,
         'test-only=s'   => \$tst_only,
         'h|help'        => \$help,
@@ -367,6 +373,7 @@ $chk_signoff = 0 if ($file);
 
 my @rawlines = ();
 my @lines = ();
+my @fixed = ();
 my $vname;
 for my $filename (@ARGV) {
         my $FILE;
@@ -394,6 +401,7 @@ for my $filename (@ARGV) {
         }
         @rawlines = ();
         @lines = ();
+        @fixed = ();
 }
 
 exit($exit);
@@ -434,7 +442,7 @@ sub parse_email {
                 $comment = $2 if defined $2;
                 $formatted_email =~ s/$address.*$//;
                 $name = $formatted_email;
-                $name =~ s/^\s+|\s+$//g;
+                $name = trim($name);
                 $name =~ s/^\"|\"$//g;
                 # If there's a name left after stripping spaces and
                 # leading quotes, and the address doesn't have both
@@ -449,9 +457,9 @@ sub parse_email {
                 }
         }
 
-        $name =~ s/^\s+|\s+$//g;
+        $name = trim($name);
         $name =~ s/^\"|\"$//g;
-        $address =~ s/^\s+|\s+$//g;
+        $address = trim($address);
         $address =~ s/^\<|\>$//g;
 
         if ($name =~ /[^\w \-]/i) { ##has "must quote" chars
@@ -467,9 +475,9 @@ sub format_email {
 
         my $formatted_email;
 
-        $name =~ s/^\s+|\s+$//g;
+        $name = trim($name);
         $name =~ s/^\"|\"$//g;
-        $address =~ s/^\s+|\s+$//g;
+        $address = trim($address);
 
         if ($name =~ /[^\w \-]/i) { ##has "must quote" chars
                 $name =~ s/(?<!\\)"/\\"/g; ##escape quotes
@@ -1291,19 +1299,25 @@ sub ERROR {
         if (report("ERROR", $_[0], $_[1])) {
                 our $clean = 0;
                 our $cnt_error++;
+                return 1;
         }
+        return 0;
 }
 sub WARN {
         if (report("WARNING", $_[0], $_[1])) {
                 our $clean = 0;
                 our $cnt_warn++;
+                return 1;
         }
+        return 0;
 }
 sub CHK {
         if ($check && report("CHECK", $_[0], $_[1])) {
                 our $clean = 0;
                 our $cnt_chk++;
+                return 1;
         }
+        return 0;
 }
 
 sub check_absolute_file {
@@ -1334,6 +1348,29 @@ sub check_absolute_file {
         }
 }
 
+sub trim {
+        my ($string) = @_;
+
+        $string =~ s/(^\s+|\s+$)//g;
+
+        return $string;
+}
+
+sub tabify {
+        my ($leading) = @_;
+
+        my $source_indent = 8;
+        my $max_spaces_before_tab = $source_indent - 1;
+        my $spaces_to_tab = " " x $source_indent;
+
+        #convert leading spaces to tabs
+        1 while $leading =~ s@^([\t]*)$spaces_to_tab@$1\t@g;
+        #Remove spaces before a tab
+        1 while $leading =~ s@^([\t]*)( {1,$max_spaces_before_tab})\t@$1\t@g;
+
+        return "$leading";
+}
+
 sub pos_last_openparen {
         my ($line) = @_;
 
@@ -1425,6 +1462,8 @@ sub process {
                 $linenr++;
                 $line = $rawline;
 
+                push(@fixed, $rawline) if ($fix);
+
                 if ($rawline=~/^\+\+\+\s+(\S+)/) {
                         $setup_docs = 0;
                         if ($1 =~ m@Documentation/kernel-parameters.txt$@) {
@@ -1616,16 +1655,29 @@ sub process {
                                      "Non-standard signature: $sign_off\n" . $herecurr);
                         }
                         if (defined $space_before && $space_before ne "") {
-                                WARN("BAD_SIGN_OFF",
-                                     "Do not use whitespace before $ucfirst_sign_off\n" . $herecurr);
+                                if (WARN("BAD_SIGN_OFF",
+                                         "Do not use whitespace before $ucfirst_sign_off\n" . $herecurr) &&
+                                    $fix) {
+                                        $fixed[$linenr - 1] =
+                                            "$ucfirst_sign_off $email";
+                                }
                         }
                         if ($sign_off =~ /-by:$/i && $sign_off ne $ucfirst_sign_off) {
-                                WARN("BAD_SIGN_OFF",
-                                     "'$ucfirst_sign_off' is the preferred signature form\n" . $herecurr);
+                                if (WARN("BAD_SIGN_OFF",
+