scripts/checkpatch.pl

   1 #!/usr/bin/perl -w
   2 # (c) 2001, Dave Jones. <davej@codemonkey.org.uk> (the file handling bit)
   3 # (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
   4 # (c) 2007, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite, etc)
   5 # Licensed under the terms of the GNU GPL License version 2
   6
   7 use strict;
   8
   9 my $P = $0;
  10 $P =~ s@.*/@@g;
  11
  12 my $V = '0.06';
  13
  14 use Getopt::Long qw(:config no_auto_abbrev);
  15
  16 my $quiet = 0;
  17 my $tree = 1;
  18 my $chk_signoff = 1;
  19 my $chk_patch = 1;
  20 my $tst_type = 0;
  21 GetOptions(
  22         'q|quiet'       => \$quiet,
  23         'tree!'         => \$tree,
  24         'signoff!'      => \$chk_signoff,
  25         'patch!'        => \$chk_patch,
  26         'test-type!'    => \$tst_type,
  27 ) or exit;
  28
  29 my $exit = 0;
  30
  31 if ($#ARGV < 0) {
  32         print "usage: $P [options] patchfile\n";
  33         print "version: $V\n";
  34         print "options: -q           => quiet\n";
  35         print "         --no-tree    => run without a kernel tree\n";
  36         exit(1);
  37 }
  38
  39 if ($tree && !top_of_kernel_tree()) {
  40         print "Must be run from the top-level dir. of a kernel tree\n";
  41         exit(2);
  42 }
  43
  44 my @dep_includes = ();
  45 my @dep_functions = ();
  46 my $removal = 'Documentation/feature-removal-schedule.txt';
  47 if ($tree && -f $removal) {
  48         open(REMOVE, "<$removal") || die "$P: $removal: open failed - $!\n";
  49         while (<REMOVE>) {
  50                 if (/^Files:\s+(.*\S)/) {
  51                         for my $file (split(/[, ]+/, $1)) {
  52                                 if ($file =~ m@include/(.*)@) {
  53                                         push(@dep_includes, $1);
  54                                 }
  55                         }
  56
  57                 } elsif (/^Funcs:\s+(.*\S)/) {
  58                         for my $func (split(/[, ]+/, $1)) {
  59                                 push(@dep_functions, $func);
  60                         }
  61                 }
  62         }
  63 }
  64
  65 my @rawlines = ();
  66 while (<>) {
  67         chomp;
  68         push(@rawlines, $_);
  69         if (eof(ARGV)) {
  70                 if (!process($ARGV, @rawlines)) {
  71                         $exit = 1;
  72                 }
  73                 @rawlines = ();
  74         }
  75 }
  76
  77 exit($exit);
  78
  79 sub top_of_kernel_tree {
  80         if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
  81             (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
  82             (-d "Documentation") && (-d "arch") && (-d "include") &&
  83             (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
  84             (-d "kernel") && (-d "lib") && (-d "scripts")) {
  85                 return 1;
  86         }
  87         return 0;
  88 }
  89
  90 sub expand_tabs {
  91         my ($str) = @_;
  92
  93         my $res = '';
  94         my $n = 0;
  95         for my $c (split(//, $str)) {
  96                 if ($c eq "\t") {
  97                         $res .= ' ';
  98                         $n++;
  99                         for (; ($n % 8) != 0; $n++) {
 100                                 $res .= ' ';
 101                         }
 102                         next;
 103                 }
 104                 $res .= $c;
 105                 $n++;
 106         }
 107
 108         return $res;
 109 }
 110
 111 sub line_stats {
 112         my ($line) = @_;
 113
 114         # Drop the diff line leader and expand tabs
 115         $line =~ s/^.//;
 116         $line = expand_tabs($line);
 117
 118         # Pick the indent from the front of the line.
 119         my ($white) = ($line =~ /^(\s*)/);
 120
 121         return (length($line), length($white));
 122 }
 123
 124 sub sanitise_line {
 125         my ($line) = @_;
 126
 127         my $res = '';
 128         my $l = '';
 129
 130         my $quote = '';
 131
 132         foreach my $c (split(//, $line)) {
 133                 if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
 134                         if ($quote eq '') {
 135                                 $quote = $c;
 136                                 $res .= $c;
 137                                 $l = $c;
 138                                 next;
 139                         } elsif ($quote eq $c) {
 140                                 $quote = '';
 141                         }
 142                 }
 143                 if ($quote && $c ne "\t") {
 144                         $res .= "X";
 145                 } else {
 146                         $res .= $c;
 147                 }
 148
 149                 $l = $c;
 150         }
 151
 152         return $res;
 153 }
 154
 155 sub ctx_block_get {
 156         my ($linenr, $remain, $outer, $open, $close) = @_;
 157         my $line;
 158         my $start = $linenr - 1;
 159         my $blk = '';
 160         my @o;
 161         my @c;
 162         my @res = ();
 163
 164         for ($line = $start; $remain > 0; $line++) {
 165                 next if ($rawlines[$line] =~ /^-/);
 166                 $remain--;
 167
 168                 $blk .= $rawlines[$line];
 169
 170                 @o = ($blk =~ /$open/g);
 171                 @c = ($blk =~ /$close/g);
 172
 173                 if (!$outer || (scalar(@o) - scalar(@c)) == 1) {
 174                         push(@res, $rawlines[$line]);
 175                 }
 176
 177                 last if (scalar(@o) == scalar(@c));
 178         }
 179
 180         return @res;
 181 }
 182 sub ctx_block_outer {
 183         my ($linenr, $remain) = @_;
 184
 185         return ctx_block_get($linenr, $remain, 1, '\{', '\}');
 186 }
 187 sub ctx_block {
 188         my ($linenr, $remain) = @_;
 189
 190         return ctx_block_get($linenr, $remain, 0, '\{', '\}');
 191 }
 192 sub ctx_statement {
 193         my ($linenr, $remain) = @_;
 194
 195         return ctx_block_get($linenr, $remain, 0, '\(', '\)');
 196 }
 197
 198 sub ctx_locate_comment {
 199         my ($first_line, $end_line) = @_;
 200
 201         # Catch a comment on the end of the line itself.
 202         my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
 203         return $current_comment if (defined $current_comment);
 204
 205         # Look through the context and try and figure out if there is a
 206         # comment.
 207         my $in_comment = 0;
 208         $current_comment = '';
 209         for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
 210                 my $line = $rawlines[$linenr - 1];
 211                 #warn "           $line\n";
 212                 if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 213                         $in_comment = 1;
 214                 }
 215                 if ($line =~ m@/\*@) {
 216                         $in_comment = 1;
 217                 }
 218                 if (!$in_comment && $current_comment ne '') {
 219                         $current_comment = '';
 220                 }
 221                 $current_comment .= $line . "\n" if ($in_comment);
 222                 if ($line =~ m@\*/@) {
 223                         $in_comment = 0;
 224                 }
 225         }
 226
 227         chomp($current_comment);
 228         return($current_comment);
 229 }
 230 sub ctx_has_comment {
 231         my ($first_line, $end_line) = @_;
 232         my $cmt = ctx_locate_comment($first_line, $end_line);
 233
 234         ##print "LINE: $rawlines[$end_line - 1 ]\n";
 235         ##print "CMMT: $cmt\n";
 236
 237         return ($cmt ne '');
 238 }
 239
 240 sub cat_vet {
 241         my ($vet) = @_;
 242
 243         $vet =~ s/\t/^I/;
 244         $vet =~ s/$/\$/;
 245
 246         return $vet;
 247 }
 248
 249 sub process {
 250         my $filename = shift;
 251         my @lines = @_;
 252
 253         my $linenr=0;
 254         my $prevline="";
 255         my $stashline="";
 256
 257         my $length;
 258         my $indent;
 259         my $previndent=0;
 260         my $stashindent=0;
 261
 262         my $clean = 1;
 263         my $signoff = 0;
 264         my $is_patch = 0;
 265
 266         # Trace the real file/line as we go.
 267         my $realfile = '';
 268         my $realline = 0;
 269         my $realcnt = 0;
 270         my $here = '';
 271         my $in_comment = 0;
 272         my $first_line = 0;
 273
 274         my $Ident       = qr{[A-Za-z\d_]+};
 275         my $Storage     = qr{extern|static};
 276         my $Sparse      = qr{__user|__kernel|__force|__iomem};
 277         my $NonptrType  = qr{
 278                                 \b
 279                                 (?:const\s+)?
 280                                 (?:unsigned\s+)?
 281                                 (?:
 282                                         void|
 283                                         char|
 284                                         short|
 285                                         int|
 286                                         long|
 287                                         unsigned|
 288                                         float|
 289                                         double|
 290                                         long\s+int|
 291                                         long\s+long|
 292                                         long\s+long\s+int|
 293                                         struct\s+$Ident|
 294                                         union\s+$Ident|
 295                                         ${Ident}_t
 296                                 )
 297                                 (?:\s+$Sparse)*
 298                                 \b
 299                           }x;
 300         my $Type        = qr{
 301                                 \b$NonptrType\b
 302                                 (?:\s*\*+\s*const|\s*\*+)?
 303                           }x;
 304         my $Declare     = qr{(?:$Storage\s+)?$Type};
 305         my $Attribute   = qr{__read_mostly|__init|__initdata};
 306
 307         foreach my $line (@lines) {
 308                 $linenr++;
 309
 310                 my $rawline = $line;
 311
 312 #extract the filename as it passes
 313                 if ($line=~/^\+\+\+\s+(\S+)/) {
 314                         $realfile=$1;
 315                         $realfile =~ s@^[^/]*/@@;
 316                         $in_comment = 0;
 317                         next;
 318                 }
 319 #extract the line range in the file after the patch is applied
 320                 if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
 321                         $is_patch = 1;
 322                         $first_line = $linenr + 1;
 323                         $in_comment = 0;
 324                         $realline=$1-1;
 325                         if (defined $2) {
 326                                 $realcnt=$3+1;
 327                         } else {
 328                                 $realcnt=1+1;
 329                         }
 330                         next;
 331                 }
 332
 333 # track the line number as we move through the hunk, note that
 334 # new versions of GNU diff omit the leading space on completely
 335 # blank context lines so we need to count that too.
 336                 if ($line =~ /^( |\+|$)/) {
 337                         $realline++;
 338                         $realcnt-- if ($realcnt != 0);
 339
 340                         # track any sort of multi-line comment.  Obviously if
 341                         # the added text or context do not include the whole
 342                         # comment we will not see it. Such is life.
 343                         #
 344                         # Guestimate if this is a continuing comment.  If this
 345                         # is the start of a diff block and this line starts
 346                         # ' *' then it is very likely a comment.
 347                         if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 348                                 $in_comment = 1;
 349                         }
 350                         if ($line =~ m@/\*@) {
 351                                 $in_comment = 1;
 352                         }
 353                         if ($line =~ m@\*/@) {
 354                                 $in_comment = 0;
 355                         }
 356
 357                         # Measure the line length and indent.
 358                         ($length, $indent) = line_stats($line);
 359
 360                         # Track the previous line.
 361                         ($prevline, $stashline) = ($stashline, $line);
 362                         ($previndent, $stashindent) = ($stashindent, $indent);
 363                 } elsif ($realcnt == 1) {
 364                         $realcnt--;
 365                 }
 366
 367 #make up the handle for any error we report on this line
 368                 $here = "#$linenr: ";
 369                 $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
 370
 371                 my $hereline = "$here\n$line\n";
 372                 my $herecurr = "$here\n$line\n\n";
 373                 my $hereprev = "$here\n$prevline\n$line\n\n";
 374
 375 #check the patch for a signoff:
 376                 if ($line =~ /^\s*signed-off-by:/i) {
 377                         # This is a signoff, if ugly, so do not double report.
 378                         $signoff++;
 379                         if (!($line =~ /^\s*Signed-off-by:/)) {
 380                                 print "Signed-off-by: is the preferred form\n";
 381                                 print "$herecurr";
 382                                 $clean = 0;
 383                         }
 384                         if ($line =~ /^\s*signed-off-by:\S/i) {
 385                                 print "need space after Signed-off-by:\n";
 386                                 print "$herecurr";
 387                                 $clean = 0;
 388                         }
 389                 }
 390
 391 # Check for wrappage within a valid hunk of the file
 392                 if ($realcnt != 0 && $line !~ m{^(?:\+|-| |$)}) {
 393                         print "patch seems to be corrupt (line wrapped?) [$realcnt]\n";
 394                         print "$herecurr";
 395                         $clean = 0;
 396                 }
 397
 398 #ignore lines being removed
 399                 if ($line=~/^-/) {next;}
 400
 401 # check we are in a valid source file if not then ignore this hunk
 402                 next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 403
 404 #trailing whitespace
 405                 if ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
 406                         my $herevet = "$here\n" . cat_vet($line) . "\n\n";
 407                         print "trailing whitespace\n";
 408                         print "$herevet";
 409                         $clean = 0;
 410                 }
 411 #80 column limit
 412                 if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
 413                         print "line over 80 characters\n";
 414                         print "$herecurr";
 415                         $clean = 0;
 416                 }
 417
 418 # check we are in a valid source file *.[hc] if not then ignore this hunk
 419                 next if ($realfile !~ /\.[hc]$/);
 420
 421 # at the beginning of a line any tabs must come first and anything
 422 # more than 8 must use tabs.
 423                 if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
 424                         my $herevet = "$here\n" . cat_vet($line) . "\n\n";
 425                         print "use tabs not spaces\n";
 426                         print "$herevet";
 427                         $clean = 0;
 428                 }
 429
 430                 #
 431                 # The rest of our checks refer specifically to C style
 432                 # only apply those _outside_ comments.
 433                 #
 434                 next if ($in_comment);
 435
 436 # Remove comments from the line before processing.
 437                 $line =~ s@/\*.*\*/@@g;
 438                 $line =~ s@/\*.*@@;
 439                 $line =~ s@.*\*/@@;
 440
 441 # Standardise the strings and chars within the input to simplify matching.
 442                 $line = sanitise_line($line);
 443
 444 #
 445 # Checks which may be anchored in the context.
 446 #
 447
 448 # Check for switch () and associated case and default
 449 # statements should be at the same indent.
 450                 if ($line=~/\bswitch\s*\(.*\)/) {
 451                         my $err = '';
 452                         my $sep = '';
 453                         my @ctx = ctx_block_outer($linenr, $realcnt);
 454                         shift(@ctx);
 455                         for my $ctx (@ctx) {
 456                                 my ($clen, $cindent) = line_stats($ctx);
 457                                 if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
 458                                                         $indent != $cindent) {
 459                                         $err .= "$sep$ctx\n";
 460                                         $sep = '';
 461                                 } else {
 462                                         $sep = "[...]\n";
 463                                 }
 464                         }
 465                         if ($err ne '') {
 466                                 print "switch and case should be at the same indent\n";
 467                                 print "$here\n$line\n$err\n";
 468                                 $clean = 0;
 469                         }
 470                 }
 471
 472 #ignore lines not being added
 473                 if ($line=~/^[^\+]/) {next;}
 474
 475 # TEST: allow direct testing of the type matcher.
 476                 if ($tst_type && $line =~ /^.$Declare$/) {
 477                         print "TEST: is type $Declare\n";
 478                         print "$herecurr";
 479                         $clean = 0;
 480                         next;
 481                 }
 482
 483 #
 484 # Checks which are anchored on the added line.
 485 #
 486
 487 # check for malformed paths in #include statements (uses RAW line)
 488                 if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
 489                         my $path = $1;
 490                         if ($path =~ m{//}) {
 491                                 print "malformed #include filename\n";
 492                                 print "$herecurr";
 493                                 $clean = 0;
 494                         }
 495                         # Sanitise this special form of string.
 496                         $path = 'X' x length($path);
 497                         $line =~ s{\<.*\>}{<$path>};
 498                 }
 499
 500 # no C99 // comments
 501                 if ($line =~ m{//}) {
 502                         print "do not use C99 // comments\n";
 503                         print "$herecurr";
 504                         $clean = 0;
 505                 }
 506                 # Remove C99 comments.
 507                 $line =~ s@//.*@@;
 508
 509 #EXPORT_SYMBOL should immediately follow its function closing }.
 510                 if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
 511                     ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
 512                         my $name = $1;
 513                         if (($prevline !~ /^}/) &&
 514                            ($prevline !~ /^\+}/) &&
 515                            ($prevline !~ /^ }/) &&
 516                            ($prevline !~ /\s$name(?:\s+$Attribute)?\s*(?:;|=)/)) {
 517                                 print "EXPORT_SYMBOL(foo); should immediately follow its function/variable\n";
 518                                 print "$herecurr";
 519                                 $clean = 0;
 520                         }
 521                 }
 522
 523 # check for static initialisers.
 524                 if ($line=~/\s*static\s.*=\s+(0|NULL);/) {
 525                         print "do not initialise statics to 0 or NULL\n";
 526                         print "$herecurr";
 527                         $clean = 0;
 528                 }
 529
 530 # check for new typedefs, only function parameters and sparse annotations
 531 # make sense.
 532                 if ($line =~ /\btypedef\s/ &&
 533                     $line !~ /\btypedef\s+$Type\s+\(\s*$Ident\s*\)\s*\(/ &&
 534                     $line !~ /\b__bitwise(?:__|)\b/) {
 535                         print "do not add new typedefs\n";
 536                         print "$herecurr";
 537                         $clean = 0;
 538                 }
 539
 540 # * goes on variable not on type
 541                 if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
 542                         print "\"(foo$1)\" should be \"(foo $1)\"\n";
 543                         print "$herecurr";
 544                         $clean = 0;
 545
 546                 } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
 547                         print "\"(foo $1 )\" should be \"(foo $1)\"\n";
 548                         print "$herecurr";
 549                         $clean = 0;
 550
 551                 } elsif ($line =~ m{$NonptrType(\*+)(?:\s+const)?\s+[A-Za-z\d_]+}) {
 552                         print "\"foo$1 bar\" should be \"foo $1bar\"\n";
 553                         print "$herecurr";
 554                         $clean = 0;
 555
 556                 } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+const)\s+[A-Za-z\d_]+}) {
 557                         print "\"foo $1 bar\" should be \"foo $1bar\"\n";
 558                         print "$herecurr";
 559                         $clean = 0;
 560                 }
 561
 562 # # no BUG() or BUG_ON()
 563 #               if ($line =~ /\b(BUG|BUG_ON)\b/) {
 564 #                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
 565 #                       print "$herecurr";
 566 #                       $clean = 0;
 567 #               }
 568
 569 # printk should use KERN_* levels.  Note that follow on printk's on the
 570 # same line do not need a level, so we use the current block context
 571 # to try and find and validate the current printk.  In summary the current
 572 # printk includes all preceeding printk's which have no newline on the end.
 573 # we assume the first bad printk is the one to report.
 574                 if ($line =~ /\bprintk\((?!KERN_)/) {
 575                         my $ok = 0;
 576                         for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
 577                                 #print "CHECK<$lines[$ln - 1]\n";
 578                                 # we have a preceeding printk if it ends
 579                                 # with "\n" ignore it, else it is to blame
 580                                 if ($lines[$ln - 1] =~ m{\bprintk\(}) {
 581                                         if ($rawlines[$ln - 1] !~ m{\\n"}) {
 582                                                 $ok = 1;
 583                                         }
 584                                         last;
 585                                 }
 586                         }
 587                         if ($ok == 0) {
 588                                 print "printk() should include KERN_ facility level\n";
 589                                 print "$herecurr";
 590                                 $clean = 0;
 591                         }
 592                 }
 593
 594 # function brace can't be on same line, except for #defines of do while,
 595 # or if closed on same line
 596                 if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
 597                     !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
 598                         print "braces following function declarations go on the next line\n";
 599                         print "$herecurr";
 600                         $clean = 0;
 601                 }
 602
 603 # Check operator spacing.
 604                 # Note we expand the line with the leading + as the real
 605                 # line will be displayed with the leading + and the tabs
 606                 # will therefore also expand that way.
 607                 my $opline = $line;
 608                 $opline = expand_tabs($opline);
 609                 $opline =~ s/^./ /;
 610                 if (!($line=~/\#\s*include/)) {
 611                         my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
 612                         my $off = 0;
 613                         for (my $n = 0; $n < $#elements; $n += 2) {
 614                                 $off += length($elements[$n]);
 615
 616                                 my $a = '';
 617                                 $a = 'V' if ($elements[$n] ne '');
 618                                 $a = 'W' if ($elements[$n] =~ /\s$/);
 619                                 $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
 620                                 $a = 'O' if ($elements[$n] eq '');
 621                                 $a = 'E' if ($elements[$n] eq '' && $n == 0);
 622
 623                                 my $op = $elements[$n + 1];
 624
 625                                 my $c = '';
 626                                 if (defined $elements[$n + 2]) {
 627                                         $c = 'V' if ($elements[$n + 2] ne '');
 628                                         $c = 'W' if ($elements[$n + 2] =~ /^\s/);
 629                                         $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
 630                                         $c = 'O' if ($elements[$n + 2] eq '');
 631                                 } else {
 632                                         $c = 'E';
 633                                 }
 634
 635                                 # Pick up the preceeding and succeeding characters.
 636                                 my $ca = substr($opline, $off - 1, 1);
 637                                 my $cc = '';
 638                                 if (length($opline) >= ($off + length($elements[$n + 1]))) {
 639                                         $cc = substr($opline, $off + length($elements[$n + 1]));
 640                                 }
 641
 642                                 my $ctx = "${a}x${c}";
 643
 644                                 my $at = "(ctx:$ctx)";
 645
 646                                 my $ptr = (" " x $off) . "^";
 647                                 my $hereptr = "$hereline$ptr\n\n";
 648
 649                                 ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
 650
 651                                 # ; should have either the end of line or a space or \ after it
 652                                 if ($op eq ';') {
 653                                         if ($ctx !~ /.x[WE]/ && $cc !~ /^\\/) {
 654                                                 print "need space after that '$op' $at\n";
 655                                                 print "$hereptr";
 656                                                 $clean = 0;
 657                                         }
 658
 659                                 # // is a comment
 660                                 } elsif ($op eq '//') {
 661
 662                                 # -> should have no spaces
 663                                 } elsif ($op eq '->') {
 664                                         if ($ctx =~ /Wx.|.xW/) {
 665                                                 print "no spaces around that '$op' $at\n";
 666                                                 print "$hereptr";
 667                                                 $clean = 0;
 668                                         }
 669
 670                                 # , must have a space on the right.
 671                                 } elsif ($op eq ',') {
 672                                         if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
 673                                                 print "need space after that '$op' $at\n";
 674                                                 print "$hereptr";
 675                                                 $clean = 0;
 676                                         }
 677
 678                                 # unary ! and unary ~ are allowed no space on the right
 679                                 } elsif ($op eq '!' or $op eq '~') {
 680                                         if ($ctx !~ /[WOEB]x./) {
 681                                                 print "need space before that '$op' $at\n";
 682                                                 print "$hereptr";
 683                                                 $clean = 0;
 684                                         }
 685                                         if ($ctx =~ /.xW/) {
 686                                                 print "no space after that '$op' $at\n";
 687                                                 print "$hereptr";
 688                                                 $clean = 0;
 689                                         }
 690
 691                                 # unary ++ and unary -- are allowed no space on one side.
 692                                 } elsif ($op eq '++' or $op eq '--') {
 693                                         if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
 694                                                 print "need space one side of that '$op' $at\n";
 695                                                 print "$hereptr";
 696                                                 $clean = 0;
 697                                         }
 698                                         if ($ctx =~ /Wx./ && $cc =~ /^;/) {
 699                                                 print "no space before that '$op' $at\n";
 700                                                 print "$hereptr";
 701                                                 $clean = 0;
 702                                         }
 703
 704                                 # & is both unary and binary
 705                                 # unary:
 706                                 #       a &b
 707                                 # binary (consistent spacing):
 708                                 #       a&b             OK
 709                                 #       a & b           OK
 710                                 #
 711                                 # boiling down to: if there is a space on the right then there
 712                                 # should be one on the left.
 713                                 #
 714                                 # - is the same
 715                                 #
 716                                 } elsif ($op eq '&' or $op eq '-') {
 717                                         if ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]/) {
 718                                                 print "need space before that '$op' $at\n";
 719                                                 print "$hereptr";
 720                                                 $clean = 0;
 721                                         }
 722
 723                                 # * is the same as & only adding:
 724                                 # type:
 725                                 #       (foo *)
 726                                 #       (foo **)
 727                                 #
 728                                 } elsif ($op eq '*') {
 729                                         if ($ca eq '*') {
 730                                                 if ($cc =~ /^\s(?!\s*const)/) {
 731                                                         print "no space after that '$op' $at\n";
 732                                                         print "$hereptr";
 733                                                         $clean = 0;
 734                                                 }
 735                                         } elsif ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]|OxV|WxB|BxB/) {
 736                                                 print "need space before that '$op' $at\n";
 737                                                 print "$hereptr";
 738                                                 $clean = 0;
 739                                         }
 740
 741                                 # << and >> may either have or not have spaces both sides
 742                                 } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
 743                                          $op eq '^' or $op eq '|')
 744                                 {
 745                                         if ($ctx !~ /VxV|WxW|VxE|WxE/) {
 746                                                 print "need consistent spacing around '$op' $at\n";
 747                                                 print "$hereptr";
 748                                                 $clean = 0;
 749                                         }
 750
 751                                 # All the others need spaces both sides.
 752                                 } elsif ($ctx !~ /[EW]x[WE]/) {
 753                                         print "need spaces around that '$op' $at\n";
 754                                         print "$hereptr";
 755                                         $clean = 0;
 756                                 }
 757                                 $off += length($elements[$n + 1]);
 758                         }
 759                 }
 760
 761 #need space before brace following if, while, etc
 762                 if ($line=~/\(.*\){/) {
 763                         print "need a space before the brace\n";
 764                         print "$herecurr";
 765                         $clean = 0;
 766                 }
 767
 768 #goto labels aren't indented, allow a single space however
 769                 if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
 770                    !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
 771                         print "labels should not be indented\n";
 772                         print "$herecurr";
 773                         $clean = 0;
 774                 }
 775
 776 # Need a space before open parenthesis after if, while etc
 777                 if ($line=~/\b(if|while|for|switch)\(/) {
 778                         print "need a space before the open parenthesis\n";
 779                         print "$herecurr";
 780                         $clean = 0;
 781                 }
 782
 783 # Check for illegal assignment in if conditional.
 784                 if ($line=~/\bif\s*\(.*[^<>!=]=[^=].*\)/) {
 785                         #next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
 786                         print "do not use assignment in if condition\n";
 787                         print "$herecurr";
 788                         $clean = 0;
 789                 }
 790
 791                 # Check for }<nl>else {, these must be at the same
 792                 # indent level to be relevant to each other.
 793                 if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
 794                                                 $previndent == $indent) {
 795                         print "else should follow close brace\n";
 796                         print "$hereprev";
 797                         $clean = 0;
 798                 }
 799
 800 #studly caps, commented out until figure out how to distinguish between use of existing and adding new
 801 #               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
 802 #                   print "No studly caps, use _\n";
 803 #                   print "$herecurr";
 804 #                   $clean = 0;
 805 #               }
 806
 807 #no spaces allowed after \ in define
 808                 if ($line=~/\#define.*\\\s$/) {
 809                         print("Whitepspace after \\ makes next lines useless\n");
 810                         print "$herecurr";
 811                         $clean = 0;
 812                 }
 813
 814 #warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
 815                 if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
 816                         my $checkfile = "include/linux/$1.h";
 817                         if (-f $checkfile) {
 818                                 print "Use #include <linux/$1.h> instead of <asm/$1.h>\n";
 819                                 print $herecurr;
 820                                 $clean = 0;
 821                         }
 822                 }
 823
 824 # if/while/etc brace do not go on next line, unless defining a do while loop,
 825 # or if that brace on the next line is for something else
 826                 if ($prevline=~/\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/) {
 827                         my @opened = $prevline=~/\(/g;
 828                         my @closed = $prevline=~/\)/g;
 829                         my $nr_line = $linenr;
 830                         my $remaining = $realcnt - 1;
 831                         my $next_line = $line;
 832                         my $extra_lines = 0;
 833                         my $display_segment = $prevline;
 834
 835                         while ($remaining > 0 && scalar @opened > scalar @closed) {
 836                                 $prevline .= $next_line;
 837                                 $display_segment .= "\n" . $next_line;
 838                                 $next_line = $lines[$nr_line];
 839                                 $nr_line++;
 840                                 $remaining--;
 841
 842                                 @opened = $prevline=~/\(/g;
 843                                 @closed = $prevline=~/\)/g;
 844                         }
 845
 846                         if (($prevline=~/\b(?:(if|while|for|switch)\s*\(.*\)|do|else)\s*$/) and ($next_line=~/{/) and
 847                            !($next_line=~/\b(?:if|while|for|switch|do|else)\b/) and !($next_line=~/\#define.*do.*while/)) {
 848                                 print "That { should be on the previous line\n";
 849                                 print "$here\n$display_segment\n$next_line\n\n";
 850                                 $clean = 0;
 851                         }
 852                 }
 853
 854 # if and else should not have general statements after it
 855                 if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
 856                     $1 !~ /^\s*(?:\sif|{|$)/) {
 857                         print "trailing statements should be on next line\n";
 858                         print "$herecurr";
 859                         $clean = 0;
 860                 }
 861
 862 # multi-statement macros should be enclosed in a do while loop, grab the
 863 # first statement and ensure its the whole macro if its not enclosed
 864 # in a known goot container
 865                 if (($prevline=~/\#define.*\\/) and
 866                    !($prevline=~/do\s+{/) and !($prevline=~/\(\{/) and
 867                    !($line=~/do.*{/) and !($line=~/\(\{/) and
 868                    !($line=~/^.\s*$Declare\s/)) {
 869                         # Grab the first statement, if that is the entire macro
 870                         # its ok.  This may start either on the #define line
 871                         # or the one below.
 872                         my $ln = $linenr;
 873                         my $cnt = $realcnt;
 874
 875                         # If the macro starts on the define line start there.
 876                         if ($prevline !~ m{^.#\s*define\s*$Ident(?:\([^\)]*\))?\s*\\\s*$}) {
 877                                 $ln--;
 878                                 $cnt++;
 879                         }
 880                         my $ctx = join('', ctx_statement($ln, $cnt));
 881
 882                         if ($ctx =~ /\\$/) {
 883                                 if ($ctx =~ /;/) {
 884                                         print "Macros with multiple statements should be enclosed in a do - while loop\n";
 885                                 } else {
 886                                         print "Macros with complex values should be enclosed in parenthesis\n";
 887                                 }
 888                                 print "$hereprev";
 889                                 $clean = 0;
 890                         }
 891                 }
 892
 893 # don't include deprecated include files (uses RAW line)
 894                 for my $inc (@dep_includes) {
 895                         if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
 896                                 print "Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n";
 897                                 print "$herecurr";
 898                                 $clean = 0;
 899                         }
 900                 }
 901
 902 # don't use deprecated functions
 903                 for my $func (@dep_functions) {
 904                         if ($line =~ /\b$func\b/) {
 905                                 print "Don't use $func(): see Documentation/feature-removal-schedule.txt\n";
 906                                 print "$herecurr";
 907                                 $clean = 0;
 908                         }
 909                 }
 910
 911 # no volatiles please
 912                 if ($line =~ /\bvolatile\b/ && $line !~ /\basm\s+volatile\b/) {
 913                         print "Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n";
 914                         print "$herecurr";
 915                         $clean = 0;
 916                 }
 917
 918 # warn about #if 0
 919                 if ($line =~ /^.#\s*if\s+0\b/) {
 920                         print "#if 0 -- if this code redundant remove it\n";
 921                         print "$herecurr";
 922                         $clean = 0;
 923                 }
 924
 925 # warn about #ifdefs in C files
 926 #               if ($line =~ /^.#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
 927 #                       print "#ifdef in C files should be avoided\n";
 928 #                       print "$herecurr";
 929 #                       $clean = 0;
 930 #               }
 931
 932 # check for spinlock_t definitions without a comment.
 933                 if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
 934                         my $which = $1;
 935                         if (!ctx_has_comment($first_line, $linenr)) {
 936                                 print "$1 definition without comment\n";
 937                                 print "$herecurr";
 938                                 $clean = 0;
 939                         }
 940                 }
 941 # check for memory barriers without a comment.
 942                 if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
 943                         if (!ctx_has_comment($first_line, $linenr)) {
 944                                 print "memory barrier without comment\n";
 945                                 print "$herecurr";
 946                                 $clean = 0;
 947                         }
 948                 }
 949 # check of hardware specific defines
 950                 if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@) {
 951                         print "architecture specific defines should be avoided\n";
 952                         print "$herecurr";
 953                         $clean = 0;
 954                 }
 955
 956                 if ($line =~ /$Type\s+(?:inline|__always_inline)\b/ ||
 957                     $line =~ /\b(?:inline|always_inline)\s+$Storage/) {
 958                         print "inline keyword should sit between storage class and type\n";
 959                         print "$herecurr";
 960                         $clean = 0;
 961                 }
 962         }
 963
 964         if ($chk_patch && !$is_patch) {
 965                 $clean = 0;
 966                 print "Does not appear to be a unified-diff format patch\n";
 967         }
 968         if ($is_patch && $chk_signoff && $signoff == 0) {
 969                 $clean = 0;
 970                 print "Missing Signed-off-by: line(s)\n";
 971         }
 972
 973         if ($clean == 1 && $quiet == 0) {
 974                 print "Your patch has no obvious style problems and is ready for submission.\n"
 975         }
 976         if ($clean == 0 && $quiet == 0) {
 977                 print "Your patch has style problems, please review.  If any of these errors\n";
 978                 print "are false positives report them to the maintainer, see\n";
 979                 print "CHECKPATCH in MAINTAINERS.\n";
 980         }
 981         return $clean;
 982 }