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 = '0.08';
  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 (/^Check:\s+(.*\S)/) {
  51                         for my $entry (split(/[, ]+/, $1)) {
  52                                 if ($entry =~ m@include/(.*)@) {
  53                                         push(@dep_includes, $1);
  54
  55                                 } elsif ($entry !~ m@/@) {
  56                                         push(@dep_functions, $entry);
  57                                 }
  58                         }
  59                 }
  60         }
  61 }
  62
  63 my @rawlines = ();
  64 while (<>) {
  65         chomp;
  66         push(@rawlines, $_);
  67         if (eof(ARGV)) {
  68                 if (!process($ARGV, @rawlines)) {
  69                         $exit = 1;
  70                 }
  71                 @rawlines = ();
  72         }
  73 }
  74
  75 exit($exit);
  76
  77 sub top_of_kernel_tree {
  78         if ((-f "COPYING") && (-f "CREDITS") && (-f "Kbuild") &&
  79             (-f "MAINTAINERS") && (-f "Makefile") && (-f "README") &&
  80             (-d "Documentation") && (-d "arch") && (-d "include") &&
  81             (-d "drivers") && (-d "fs") && (-d "init") && (-d "ipc") &&
  82             (-d "kernel") && (-d "lib") && (-d "scripts")) {
  83                 return 1;
  84         }
  85         return 0;
  86 }
  87
  88 sub expand_tabs {
  89         my ($str) = @_;
  90
  91         my $res = '';
  92         my $n = 0;
  93         for my $c (split(//, $str)) {
  94                 if ($c eq "\t") {
  95                         $res .= ' ';
  96                         $n++;
  97                         for (; ($n % 8) != 0; $n++) {
  98                                 $res .= ' ';
  99                         }
 100                         next;
 101                 }
 102                 $res .= $c;
 103                 $n++;
 104         }
 105
 106         return $res;
 107 }
 108
 109 sub line_stats {
 110         my ($line) = @_;
 111
 112         # Drop the diff line leader and expand tabs
 113         $line =~ s/^.//;
 114         $line = expand_tabs($line);
 115
 116         # Pick the indent from the front of the line.
 117         my ($white) = ($line =~ /^(\s*)/);
 118
 119         return (length($line), length($white));
 120 }
 121
 122 sub sanitise_line {
 123         my ($line) = @_;
 124
 125         my $res = '';
 126         my $l = '';
 127
 128         my $quote = '';
 129
 130         foreach my $c (split(//, $line)) {
 131                 if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
 132                         if ($quote eq '') {
 133                                 $quote = $c;
 134                                 $res .= $c;
 135                                 $l = $c;
 136                                 next;
 137                         } elsif ($quote eq $c) {
 138                                 $quote = '';
 139                         }
 140                 }
 141                 if ($quote && $c ne "\t") {
 142                         $res .= "X";
 143                 } else {
 144                         $res .= $c;
 145                 }
 146
 147                 $l = $c;
 148         }
 149
 150         return $res;
 151 }
 152
 153 sub ctx_block_get {
 154         my ($linenr, $remain, $outer, $open, $close, $off) = @_;
 155         my $line;
 156         my $start = $linenr - 1;
 157         my $blk = '';
 158         my @o;
 159         my @c;
 160         my @res = ();
 161
 162         my $level = 0;
 163         for ($line = $start; $remain > 0; $line++) {
 164                 next if ($rawlines[$line] =~ /^-/);
 165                 $remain--;
 166
 167                 $blk .= $rawlines[$line];
 168                 foreach my $c (split(//, $rawlines[$line])) {
 169                         ##print "C<$c>L<$level><$open$close>O<$off>\n";
 170                         if ($off > 0) {
 171                                 $off--;
 172                                 next;
 173                         }
 174
 175                         if ($c eq $close && $level > 0) {
 176                                 $level--;
 177                                 last if ($level == 0);
 178                         } elsif ($c eq $open) {
 179                                 $level++;
 180                         }
 181                 }
 182
 183                 if (!$outer || $level <= 1) {
 184                         push(@res, $rawlines[$line]);
 185                 }
 186
 187                 last if ($level == 0);
 188         }
 189
 190         return ($level, @res);
 191 }
 192 sub ctx_block_outer {
 193         my ($linenr, $remain) = @_;
 194
 195         my ($level, @r) = ctx_block_get($linenr, $remain, 1, '{', '}', 0);
 196         return @r;
 197 }
 198 sub ctx_block {
 199         my ($linenr, $remain) = @_;
 200
 201         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 202         return @r;
 203 }
 204 sub ctx_statement {
 205         my ($linenr, $remain, $off) = @_;
 206
 207         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '(', ')', $off);
 208         return @r;
 209 }
 210 sub ctx_block_level {
 211         my ($linenr, $remain) = @_;
 212
 213         return ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 214 }
 215
 216 sub ctx_locate_comment {
 217         my ($first_line, $end_line) = @_;
 218
 219         # Catch a comment on the end of the line itself.
 220         my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
 221         return $current_comment if (defined $current_comment);
 222
 223         # Look through the context and try and figure out if there is a
 224         # comment.
 225         my $in_comment = 0;
 226         $current_comment = '';
 227         for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
 228                 my $line = $rawlines[$linenr - 1];
 229                 #warn "           $line\n";
 230                 if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 231                         $in_comment = 1;
 232                 }
 233                 if ($line =~ m@/\*@) {
 234                         $in_comment = 1;
 235                 }
 236                 if (!$in_comment && $current_comment ne '') {
 237                         $current_comment = '';
 238                 }
 239                 $current_comment .= $line . "\n" if ($in_comment);
 240                 if ($line =~ m@\*/@) {
 241                         $in_comment = 0;
 242                 }
 243         }
 244
 245         chomp($current_comment);
 246         return($current_comment);
 247 }
 248 sub ctx_has_comment {
 249         my ($first_line, $end_line) = @_;
 250         my $cmt = ctx_locate_comment($first_line, $end_line);
 251
 252         ##print "LINE: $rawlines[$end_line - 1 ]\n";
 253         ##print "CMMT: $cmt\n";
 254
 255         return ($cmt ne '');
 256 }
 257
 258 sub cat_vet {
 259         my ($vet) = @_;
 260
 261         $vet =~ s/\t/^I/;
 262         $vet =~ s/$/\$/;
 263
 264         return $vet;
 265 }
 266
 267 my @report = ();
 268 sub report {
 269         push(@report, $_[0]);
 270 }
 271 sub report_dump {
 272         @report;
 273 }
 274 sub ERROR {
 275         report("ERROR: $_[0]\n");
 276         our $clean = 0;
 277 }
 278 sub WARN {
 279         report("WARNING: $_[0]\n");
 280         our $clean = 0;
 281 }
 282 sub CHK {
 283         report("CHECK: $_[0]\n");
 284         our $clean = 0;
 285 }
 286
 287 sub process {
 288         my $filename = shift;
 289         my @lines = @_;
 290
 291         my $linenr=0;
 292         my $prevline="";
 293         my $stashline="";
 294
 295         my $length;
 296         my $indent;
 297         my $previndent=0;
 298         my $stashindent=0;
 299
 300         our $clean = 1;
 301         my $signoff = 0;
 302         my $is_patch = 0;
 303
 304         # Trace the real file/line as we go.
 305         my $realfile = '';
 306         my $realline = 0;
 307         my $realcnt = 0;
 308         my $here = '';
 309         my $in_comment = 0;
 310         my $first_line = 0;
 311
 312         my $Ident       = qr{[A-Za-z\d_]+};
 313         my $Storage     = qr{extern|static};
 314         my $Sparse      = qr{__user|__kernel|__force|__iomem};
 315         my $NonptrType  = qr{
 316                                 \b
 317                                 (?:const\s+)?
 318                                 (?:unsigned\s+)?
 319                                 (?:
 320                                         void|
 321                                         char|
 322                                         short|
 323                                         int|
 324                                         long|
 325                                         unsigned|
 326                                         float|
 327                                         double|
 328                                         long\s+int|
 329                                         long\s+long|
 330                                         long\s+long\s+int|
 331                                         u8|u16|u32|u64|
 332                                         s8|s16|s32|s64|
 333                                         struct\s+$Ident|
 334                                         union\s+$Ident|
 335                                         enum\s+$Ident|
 336                                         ${Ident}_t
 337                                 )
 338                                 (?:\s+$Sparse)*
 339                                 \b
 340                           }x;
 341         my $Type        = qr{
 342                                 \b$NonptrType\b
 343                                 (?:\s*\*+\s*const|\s*\*+)?
 344                           }x;
 345         my $Declare     = qr{(?:$Storage\s+)?$Type};
 346         my $Attribute   = qr{const|__read_mostly|__init|__initdata|__meminit};
 347
 348         my $Member      = qr{->$Ident|\.$Ident|\[[^]]*\]};
 349         my $Lval        = qr{$Ident(?:$Member)*};
 350
 351         # Pre-scan the patch looking for any __setup documentation.
 352         my @setup_docs = ();
 353         my $setup_docs = 0;
 354         foreach my $line (@lines) {
 355                 if ($line=~/^\+\+\+\s+(\S+)/) {
 356                         $setup_docs = 0;
 357                         if ($1 =~ m@Documentation/kernel-parameters.txt$@) {
 358                                 $setup_docs = 1;
 359                         }
 360                         next;
 361                 }
 362
 363                 if ($setup_docs && $line =~ /^\+/) {
 364                         push(@setup_docs, $line);
 365                 }
 366         }
 367
 368         foreach my $line (@lines) {
 369                 $linenr++;
 370
 371                 my $rawline = $line;
 372
 373 #extract the filename as it passes
 374                 if ($line=~/^\+\+\+\s+(\S+)/) {
 375                         $realfile=$1;
 376                         $realfile =~ s@^[^/]*/@@;
 377                         $in_comment = 0;
 378                         next;
 379                 }
 380 #extract the line range in the file after the patch is applied
 381                 if ($line=~/^\@\@ -\d+,\d+ \+(\d+)(,(\d+))? \@\@/) {
 382                         $is_patch = 1;
 383                         $first_line = $linenr + 1;
 384                         $in_comment = 0;
 385                         $realline=$1-1;
 386                         if (defined $2) {
 387                                 $realcnt=$3+1;
 388                         } else {
 389                                 $realcnt=1+1;
 390                         }
 391                         next;
 392                 }
 393
 394 # track the line number as we move through the hunk, note that
 395 # new versions of GNU diff omit the leading space on completely
 396 # blank context lines so we need to count that too.
 397                 if ($line =~ /^( |\+|$)/) {
 398                         $realline++;
 399                         $realcnt-- if ($realcnt != 0);
 400
 401                         # track any sort of multi-line comment.  Obviously if
 402                         # the added text or context do not include the whole
 403                         # comment we will not see it. Such is life.
 404                         #
 405                         # Guestimate if this is a continuing comment.  If this
 406                         # is the start of a diff block and this line starts
 407                         # ' *' then it is very likely a comment.
 408                         if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 409                                 $in_comment = 1;
 410                         }
 411                         if ($line =~ m@/\*@) {
 412                                 $in_comment = 1;
 413                         }
 414                         if ($line =~ m@\*/@) {
 415                                 $in_comment = 0;
 416                         }
 417
 418                         # Measure the line length and indent.
 419                         ($length, $indent) = line_stats($line);
 420
 421                         # Track the previous line.
 422                         ($prevline, $stashline) = ($stashline, $line);
 423                         ($previndent, $stashindent) = ($stashindent, $indent);
 424                 } elsif ($realcnt == 1) {
 425                         $realcnt--;
 426                 }
 427
 428 #make up the handle for any error we report on this line
 429                 $here = "#$linenr: ";
 430                 $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
 431
 432                 my $hereline = "$here\n$line\n";
 433                 my $herecurr = "$here\n$line\n";
 434                 my $hereprev = "$here\n$prevline\n$line\n";
 435
 436 #check the patch for a signoff:
 437                 if ($line =~ /^\s*signed-off-by:/i) {
 438                         # This is a signoff, if ugly, so do not double report.
 439                         $signoff++;
 440                         if (!($line =~ /^\s*Signed-off-by:/)) {
 441                                 WARN("Signed-off-by: is the preferred form\n" .
 442                                         $herecurr);
 443                         }
 444                         if ($line =~ /^\s*signed-off-by:\S/i) {
 445                                 WARN("need space after Signed-off-by:\n" .
 446                                         $herecurr);
 447                         }
 448                 }
 449
 450 # Check for wrappage within a valid hunk of the file
 451                 if ($realcnt != 0 && $line !~ m{^(?:\+|-| |$)}) {
 452                         ERROR("patch seems to be corrupt (line wrapped?)\n" .
 453                                 $herecurr);
 454                 }
 455
 456 # UTF-8 regex found at http://www.w3.org/International/questions/qa-forms-utf-8.en.php
 457                 if (($realfile =~ /^$/ || $line =~ /^\+/) &&
 458                      !($line =~ m/^(
 459                                 [\x09\x0A\x0D\x20-\x7E]              # ASCII
 460                                 | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
 461                                 |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
 462                                 | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
 463                                 |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
 464                                 |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
 465                                 | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
 466                                 |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
 467                                 )*$/x )) {
 468                         ERROR("Invalid UTF-8\n" . $herecurr);
 469                 }
 470
 471 #ignore lines being removed
 472                 if ($line=~/^-/) {next;}
 473
 474 # check we are in a valid source file if not then ignore this hunk
 475                 next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 476
 477 #trailing whitespace
 478                 if ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
 479                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 480                         ERROR("trailing whitespace\n" . $herevet);
 481                 }
 482 #80 column limit
 483                 if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
 484                         WARN("line over 80 characters\n" . $herecurr);
 485                 }
 486
 487 # check we are in a valid source file *.[hc] if not then ignore this hunk
 488                 next if ($realfile !~ /\.[hc]$/);
 489
 490 # at the beginning of a line any tabs must come first and anything
 491 # more than 8 must use tabs.
 492                 if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
 493                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 494                         ERROR("use tabs not spaces\n" . $herevet);
 495                 }
 496
 497                 #
 498                 # The rest of our checks refer specifically to C style
 499                 # only apply those _outside_ comments.
 500                 #
 501                 next if ($in_comment);
 502
 503 # Remove comments from the line before processing.
 504                 $line =~ s@/\*.*\*/@@g;
 505                 $line =~ s@/\*.*@@;
 506                 $line =~ s@.*\*/@@;
 507
 508 # Standardise the strings and chars within the input to simplify matching.
 509                 $line = sanitise_line($line);
 510
 511 #
 512 # Checks which may be anchored in the context.
 513 #
 514
 515 # Check for switch () and associated case and default
 516 # statements should be at the same indent.
 517                 if ($line=~/\bswitch\s*\(.*\)/) {
 518                         my $err = '';
 519                         my $sep = '';
 520                         my @ctx = ctx_block_outer($linenr, $realcnt);
 521                         shift(@ctx);
 522                         for my $ctx (@ctx) {
 523                                 my ($clen, $cindent) = line_stats($ctx);
 524                                 if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
 525                                                         $indent != $cindent) {
 526                                         $err .= "$sep$ctx\n";
 527                                         $sep = '';
 528                                 } else {
 529                                         $sep = "[...]\n";
 530                                 }
 531                         }
 532                         if ($err ne '') {
 533                                 ERROR("switch and case should be at the same indent\n$hereline\n$err\n");
 534                         }
 535                 }
 536
 537 # if/while/etc brace do not go on next line, unless defining a do while loop,
 538 # or if that brace on the next line is for something else
 539                 if ($line =~ /\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.#/) {
 540                         my @ctx = ctx_statement($linenr, $realcnt, 0);
 541                         my $ctx_ln = $linenr + $#ctx + 1;
 542                         my $ctx_cnt = $realcnt - $#ctx - 1;
 543                         my $ctx = join("\n", @ctx);
 544
 545                         while ($ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^-/) {
 546                                 $ctx_ln++;
 547                                 $ctx_cnt--;
 548                         }
 549                         ##warn "line<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>";
 550
 551                         if ($ctx !~ /{\s*/ && $ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
 552                                 ERROR("That open brace { should be on the previous line\n" .
 553                                         "$here\n$ctx\n$lines[$ctx_ln - 1]");
 554                         }
 555                 }
 556
 557 #ignore lines not being added
 558                 if ($line=~/^[^\+]/) {next;}
 559
 560 # TEST: allow direct testing of the type matcher.
 561                 if ($tst_type && $line =~ /^.$Declare$/) {
 562                         ERROR("TEST: is type $Declare\n" . $herecurr);
 563                         next;
 564                 }
 565
 566 # check for initialisation to aggregates open brace on the next line
 567                 if ($prevline =~ /$Declare\s*$Ident\s*=\s*$/ &&
 568                     $line =~ /^.\s*{/) {
 569                         ERROR("That open brace { should be on the previous line\n" . $hereprev);
 570                 }
 571
 572 #
 573 # Checks which are anchored on the added line.
 574 #
 575
 576 # check for malformed paths in #include statements (uses RAW line)
 577                 if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
 578                         my $path = $1;
 579                         if ($path =~ m{//}) {
 580                                 ERROR("malformed #include filename\n" .
 581                                         $herecurr);
 582                         }
 583                         # Sanitise this special form of string.
 584                         $path = 'X' x length($path);
 585                         $line =~ s{\<.*\>}{<$path>};
 586                 }
 587
 588 # no C99 // comments
 589                 if ($line =~ m{//}) {
 590                         ERROR("do not use C99 // comments\n" . $herecurr);
 591                 }
 592                 # Remove C99 comments.
 593                 $line =~ s@//.*@@;
 594
 595 #EXPORT_SYMBOL should immediately follow its function closing }.
 596                 if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
 597                     ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
 598                         my $name = $1;
 599                         if (($prevline !~ /^}/) &&
 600                            ($prevline !~ /^\+}/) &&
 601                            ($prevline !~ /^ }/) &&
 602                            ($prevline !~ /\s$name(?:\s+$Attribute)?\s*(?:;|=)/)) {
 603                                 WARN("EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
 604                         }
 605                 }
 606
 607 # check for external initialisers.
 608                 if ($line =~ /^.$Type\s*$Ident\s*=\s*(0|NULL);/) {
 609                         ERROR("do not initialise externals to 0 or NULL\n" .
 610                                 $herecurr);
 611                 }
 612 # check for static initialisers.
 613                 if ($line =~ /\s*static\s.*=\s*(0|NULL);/) {
 614                         ERROR("do not initialise statics to 0 or NULL\n" .
 615                                 $herecurr);
 616                 }
 617
 618 # check for new typedefs, only function parameters and sparse annotations
 619 # make sense.
 620                 if ($line =~ /\btypedef\s/ &&
 621                     $line !~ /\btypedef\s+$Type\s+\(\s*\*$Ident\s*\)\s*\(/ &&
 622                     $line !~ /\b__bitwise(?:__|)\b/) {
 623                         WARN("do not add new typedefs\n" . $herecurr);
 624                 }
 625
 626 # * goes on variable not on type
 627                 if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
 628                         ERROR("\"(foo$1)\" should be \"(foo $1)\"\n" .
 629                                 $herecurr);
 630
 631                 } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
 632                         ERROR("\"(foo $1 )\" should be \"(foo $1)\"\n" .
 633                                 $herecurr);
 634
 635                 } elsif ($line =~ m{$NonptrType(\*+)(?:\s+$Attribute)?\s+[A-Za-z\d_]+}) {
 636                         ERROR("\"foo$1 bar\" should be \"foo $1bar\"\n" .
 637                                 $herecurr);
 638
 639                 } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+$Attribute)\s+[A-Za-z\d_]+}) {
 640                         ERROR("\"foo $1 bar\" should be \"foo $1bar\"\n" .
 641                                 $herecurr);
 642                 }
 643
 644 # # no BUG() or BUG_ON()
 645 #               if ($line =~ /\b(BUG|BUG_ON)\b/) {
 646 #                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
 647 #                       print "$herecurr";
 648 #                       $clean = 0;
 649 #               }
 650
 651 # printk should use KERN_* levels.  Note that follow on printk's on the
 652 # same line do not need a level, so we use the current block context
 653 # to try and find and validate the current printk.  In summary the current
 654 # printk includes all preceeding printk's which have no newline on the end.
 655 # we assume the first bad printk is the one to report.
 656                 if ($line =~ /\bprintk\((?!KERN_)\s*"/) {
 657                         my $ok = 0;
 658                         for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
 659                                 #print "CHECK<$lines[$ln - 1]\n";
 660                                 # we have a preceeding printk if it ends
 661                                 # with "\n" ignore it, else it is to blame
 662                                 if ($lines[$ln - 1] =~ m{\bprintk\(}) {
 663                                         if ($rawlines[$ln - 1] !~ m{\\n"}) {
 664                                                 $ok = 1;
 665                                         }
 666                                         last;
 667                                 }
 668                         }
 669                         if ($ok == 0) {
 670                                 WARN("printk() should include KERN_ facility level\n" . $herecurr);
 671                         }
 672                 }
 673
 674 # function brace can't be on same line, except for #defines of do while,
 675 # or if closed on same line
 676                 if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
 677                     !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
 678                         ERROR("open brace '{' following function declarations go on the next line\n" . $herecurr);
 679                 }
 680
 681 # check for spaces between functions and their parentheses.
 682                 if ($line =~ /($Ident)\s+\(/ &&
 683                     $1 !~ /^(?:if|for|while|switch|return|volatile)$/ &&
 684                     $line !~ /$Type\s+\(/ && $line !~ /^.\#\s*define\b/) {
 685                         ERROR("no space between function name and open parenthesis '('\n" . $herecurr);
 686                 }
 687 # Check operator spacing.
 688                 # Note we expand the line with the leading + as the real
 689                 # line will be displayed with the leading + and the tabs
 690                 # will therefore also expand that way.
 691                 my $opline = $line;
 692                 $opline = expand_tabs($opline);
 693                 $opline =~ s/^./ /;
 694                 if (!($line=~/\#\s*include/)) {
 695                         my @elements = split(/(<<=|>>=|<=|>=|==|!=|\+=|-=|\*=|\/=|%=|\^=|\|=|&=|=>|->|<<|>>|<|>|=|!|~|&&|\|\||,|\^|\+\+|--|;|&|\||\+|-|\*|\/\/|\/)/, $opline);
 696                         my $off = 0;
 697                         for (my $n = 0; $n < $#elements; $n += 2) {
 698                                 $off += length($elements[$n]);
 699
 700                                 my $a = '';
 701                                 $a = 'V' if ($elements[$n] ne '');
 702                                 $a = 'W' if ($elements[$n] =~ /\s$/);
 703                                 $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
 704                                 $a = 'O' if ($elements[$n] eq '');
 705                                 $a = 'E' if ($elements[$n] eq '' && $n == 0);
 706
 707                                 my $op = $elements[$n + 1];
 708
 709                                 my $c = '';
 710                                 if (defined $elements[$n + 2]) {
 711                                         $c = 'V' if ($elements[$n + 2] ne '');
 712                                         $c = 'W' if ($elements[$n + 2] =~ /^\s/);
 713                                         $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
 714                                         $c = 'O' if ($elements[$n + 2] eq '');
 715                                 } else {
 716                                         $c = 'E';
 717                                 }
 718
 719                                 # Pick up the preceeding and succeeding characters.
 720                                 my $ca = substr($opline, 0, $off);
 721                                 my $cc = '';
 722                                 if (length($opline) >= ($off + length($elements[$n + 1]))) {
 723                                         $cc = substr($opline, $off + length($elements[$n + 1]));
 724                                 }
 725                                 my $cb = "$ca$;$cc";
 726
 727                                 my $ctx = "${a}x${c}";
 728
 729                                 my $at = "(ctx:$ctx)";
 730
 731                                 my $ptr = (" " x $off) . "^";
 732                                 my $hereptr = "$hereline$ptr\n";
 733
 734                                 ##print "<$s1:$op:$s2> <$elements[$n]:$elements[$n + 1]:$elements[$n + 2]>\n";
 735
 736                                 # ; should have either the end of line or a space or \ after it
 737                                 if ($op eq ';') {
 738                                         if ($ctx !~ /.x[WEB]/ && $cc !~ /^\\/ &&
 739                                             $cc !~ /^;/) {
 740                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 741                                         }
 742
 743                                 # // is a comment
 744                                 } elsif ($op eq '//') {
 745
 746                                 # -> should have no spaces
 747                                 } elsif ($op eq '->') {
 748                                         if ($ctx =~ /Wx.|.xW/) {
 749                                                 ERROR("no spaces around that '$op' $at\n" . $hereptr);
 750                                         }
 751
 752                                 # , must have a space on the right.
 753                                 } elsif ($op eq ',') {
 754                                         if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
 755                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
 756                                         }
 757
 758                                 # unary ! and unary ~ are allowed no space on the right
 759                                 } elsif ($op eq '!' or $op eq '~') {
 760                                         if ($ctx !~ /[WOEB]x./) {
 761                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 762                                         }
 763                                         if ($ctx =~ /.xW/) {
 764                                                 ERROR("no space after that '$op' $at\n" . $hereptr);
 765                                         }
 766
 767                                 # unary ++ and unary -- are allowed no space on one side.
 768                                 } elsif ($op eq '++' or $op eq '--') {
 769                                         if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
 770                                                 ERROR("need space one side of that '$op' $at\n" . $hereptr);
 771                                         }
 772                                         if ($ctx =~ /Wx./ && $cc =~ /^;/) {
 773                                                 ERROR("no space before that '$op' $at\n" . $hereptr);
 774                                         }
 775
 776                                 # & is both unary and binary
 777                                 # unary:
 778                                 #       a &b
 779                                 # binary (consistent spacing):
 780                                 #       a&b             OK
 781                                 #       a & b           OK
 782                                 #
 783                                 # boiling down to: if there is a space on the right then there
 784                                 # should be one on the left.
 785                                 #
 786                                 # - is the same
 787                                 #
 788                                 } elsif ($op eq '&' or $op eq '-') {
 789                                         if ($ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]/) {
 790                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 791                                         }
 792
 793                                 # * is the same as & only adding:
 794                                 # type:
 795                                 #       (foo *)
 796                                 #       (foo **)
 797                                 #
 798                                 } elsif ($op eq '*') {
 799                                         if ($ca !~ /$Type$/ && $cb !~ /(\*$;|$;\*)/ &&
 800                                             $ctx !~ /VxV|[EW]x[WE]|[EWB]x[VO]|OxV|WxB|BxB/) {
 801                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
 802                                         }
 803
 804                                 # << and >> may either have or not have spaces both sides
 805                                 } elsif ($op eq '<<' or $op eq '>>' or $op eq '+' or $op eq '/' or
 806                                          $op eq '^' or $op eq '|')
 807                                 {
 808                                         if ($ctx !~ /VxV|WxW|VxE|WxE/) {
 809                                                 ERROR("need consistent spacing around '$op' $at\n" .
 810                                                         $hereptr);
 811                                         }
 812
 813                                 # All the others need spaces both sides.
 814                                 } elsif ($ctx !~ /[EW]x[WE]/) {
 815                                         ERROR("need spaces around that '$op' $at\n" . $hereptr);
 816                                 }
 817                                 $off += length($elements[$n + 1]);
 818                         }
 819                 }
 820
 821 # check for multiple assignments
 822                 if ($line =~ /^.\s*$Lval\s*=\s*$Lval\s*=(?!=)/) {
 823                         WARN("multiple assignments should be avoided\n" . $herecurr);
 824                 }
 825
 826 # check for multiple declarations, allowing for a function declaration
 827 # continuation.
 828                 if ($line =~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Ident.*/ &&
 829                     $line !~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Type\s*$Ident.*/) {
 830                         WARN("declaring multiple variables together should be avoided\n" . $herecurr);
 831                 }
 832
 833 #need space before brace following if, while, etc
 834                 if ($line =~ /\(.*\){/ || $line =~ /do{/) {
 835                         ERROR("need a space before the open brace '{'\n" . $herecurr);
 836                 }
 837
 838 # closing brace should have a space following it when it has anything
 839 # on the line
 840                 if ($line =~ /}(?!(?:,|;|\)))\S/) {
 841                         ERROR("need a space after that close brace '}'\n" . $herecurr);
 842                 }
 843
 844 #goto labels aren't indented, allow a single space however
 845                 if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
 846                    !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
 847                         WARN("labels should not be indented\n" . $herecurr);
 848                 }
 849
 850 # Need a space before open parenthesis after if, while etc
 851                 if ($line=~/\b(if|while|for|switch)\(/) {
 852                         ERROR("need a space before the open parenthesis '('\n" . $herecurr);
 853                 }
 854
 855 # Check for illegal assignment in if conditional.
 856                 if ($line=~/\bif\s*\(.*[^<>!=]=[^=].*\)/) {
 857                         #next if ($line=~/\".*\Q$op\E.*\"/ or $line=~/\'\Q$op\E\'/);
 858                         ERROR("do not use assignment in if condition\n" . $herecurr);
 859                 }
 860
 861                 # Check for }<nl>else {, these must be at the same
 862                 # indent level to be relevant to each other.
 863                 if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
 864                                                 $previndent == $indent) {
 865                         ERROR("else should follow close brace '}'\n" . $hereprev);
 866                 }
 867
 868 #studly caps, commented out until figure out how to distinguish between use of existing and adding new
 869 #               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
 870 #                   print "No studly caps, use _\n";
 871 #                   print "$herecurr";
 872 #                   $clean = 0;
 873 #               }
 874
 875 #no spaces allowed after \ in define
 876                 if ($line=~/\#define.*\\\s$/) {
 877                         WARN("Whitepspace after \\ makes next lines useless\n" . $herecurr);
 878                 }
 879
 880 #warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
 881                 if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
 882                         my $checkfile = "include/linux/$1.h";
 883                         if (-f $checkfile) {
 884                                 CHK("Use #include <linux/$1.h> instead of <asm/$1.h>\n" .
 885                                         $herecurr);
 886                         }
 887                 }
 888
 889 # if and else should not have general statements after it
 890                 if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
 891                     $1 !~ /^\s*(?:\sif|{|\\|$)/) {
 892                         ERROR("trailing statements should be on next line\n" . $herecurr);
 893                 }
 894
 895 # multi-statement macros should be enclosed in a do while loop, grab the
 896 # first statement and ensure its the whole macro if its not enclosed
 897 # in a known goot container
 898                 if (($prevline=~/\#define.*\\/) and
 899                    !($prevline=~/do\s+{/) and !($prevline=~/\(\{/) and
 900                    !($line=~/do.*{/) and !($line=~/\(\{/) and
 901                    !($line=~/^.\s*$Declare\s/)) {
 902                         # Grab the first statement, if that is the entire macro
 903                         # its ok.  This may start either on the #define line
 904                         # or the one below.
 905                         my $ln = $linenr;
 906                         my $cnt = $realcnt;
 907                         my $off = 0;
 908
 909                         # If the macro starts on the define line start
 910                         # grabbing the statement after the identifier
 911                         $prevline =~ m{^(.#\s*define\s*$Ident(?:\([^\)]*\))?\s*)(.*)\\\s*$};
 912                         ##print "1<$1> 2<$2>\n";
 913                         if ($2 ne '') {
 914                                 $off = length($1);
 915                                 $ln--;
 916                                 $cnt++;
 917                         }
 918                         my @ctx = ctx_statement($ln, $cnt, $off);
 919                         my $ctx_ln = $ln + $#ctx + 1;
 920                         my $ctx = join("\n", @ctx);
 921
 922                         # Pull in any empty extension lines.
 923                         while ($ctx =~ /\\$/ &&
 924                                $lines[$ctx_ln - 1] =~ /^.\s*(?:\\)?$/) {
 925                                 $ctx .= $lines[$ctx_ln - 1];
 926                                 $ctx_ln++;
 927                         }
 928
 929                         if ($ctx =~ /\\$/) {
 930                                 if ($ctx =~ /;/) {
 931                                         ERROR("Macros with multiple statements should be enclosed in a do - while loop\n" . "$here\n$ctx\n");
 932                                 } else {
 933                                         ERROR("Macros with complex values should be enclosed in parenthesis\n" . "$here\n$ctx\n");
 934                                 }
 935                         }
 936                 }
 937
 938 # check for redundant bracing round if etc
 939                 if ($line =~ /\b(if|while|for|else)\b/) {
 940                         # Locate the end of the opening statement.
 941                         my @control = ctx_statement($linenr, $realcnt, 0);
 942                         my $nr = $linenr + (scalar(@control) - 1);
 943                         my $cnt = $realcnt - (scalar(@control) - 1);
 944
 945                         my $off = $realcnt - $cnt;
 946                         #print "$off: line<$line>end<" . $lines[$nr - 1] . ">\n";
 947
 948                         # If this is is a braced statement group check it
 949                         if ($lines[$nr - 1] =~ /{\s*$/) {
 950                                 my ($lvl, @block) = ctx_block_level($nr, $cnt);
 951
 952                                 my $stmt = join(' ', @block);
 953                                 $stmt =~ s/^[^{]*{//;
 954                                 $stmt =~ s/}[^}]*$//;
 955
 956                                 #print "block<" . join(' ', @block) . "><" . scalar(@block) . ">\n";
 957                                 #print "stmt<$stmt>\n\n";
 958
 959                                 # Count the ;'s if there is fewer than two
 960                                 # then there can only be one statement,
 961                                 # if there is a brace inside we cannot
 962                                 # trivially detect if its one statement.
 963                                 # Also nested if's often require braces to
 964                                 # disambiguate the else binding so shhh there.
 965                                 my @semi = ($stmt =~ /;/g);
 966                                 ##print "semi<" . scalar(@semi) . ">\n";
 967                                 if ($lvl == 0 && scalar(@semi) < 2 &&
 968                                     $stmt !~ /{/ && $stmt !~ /\bif\b/) {
 969                                         my $herectx = "$here\n" . join("\n", @control, @block[1 .. $#block]) . "\n";
 970                                         shift(@block);
 971                                         ERROR("braces {} are not necessary for single statement blocks\n" . $herectx);
 972                                 }
 973                         }
 974                 }
 975
 976 # don't include deprecated include files (uses RAW line)
 977                 for my $inc (@dep_includes) {
 978                         if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
 979                                 ERROR("Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n" . $herecurr);
 980                         }
 981                 }
 982
 983 # don't use deprecated functions
 984                 for my $func (@dep_functions) {
 985                         if ($line =~ /\b$func\b/) {
 986                                 ERROR("Don't use $func(): see Documentation/feature-removal-schedule.txt\n" . $herecurr);
 987                         }
 988                 }
 989
 990 # no volatiles please
 991                 if ($line =~ /\bvolatile\b/ && $line !~ /\basm\s+volatile\b/) {
 992                         WARN("Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr);
 993                 }
 994
 995 # warn about #if 0
 996                 if ($line =~ /^.#\s*if\s+0\b/) {
 997                         CHK("if this code is redundant consider removing it\n" .
 998                                 $herecurr);
 999                 }
1000
1001 # check for needless kfree() checks
1002                 if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
1003                         my $expr = $1;
1004                         if ($line =~ /\bkfree\(\Q$expr\E\);/) {
1005                                 WARN("kfree(NULL) is safe this check is probabally not required\n" . $hereprev);
1006                         }
1007                 }
1008
1009 # warn about #ifdefs in C files
1010 #               if ($line =~ /^.#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
1011 #                       print "#ifdef in C files should be avoided\n";
1012 #                       print "$herecurr";
1013 #                       $clean = 0;
1014 #               }
1015
1016 # check for spinlock_t definitions without a comment.
1017                 if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
1018                         my $which = $1;
1019                         if (!ctx_has_comment($first_line, $linenr)) {
1020                                 CHK("$1 definition without comment\n" . $herecurr);
1021                         }
1022                 }
1023 # check for memory barriers without a comment.
1024                 if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
1025                         if (!ctx_has_comment($first_line, $linenr)) {
1026                                 CHK("memory barrier without comment\n" . $herecurr);
1027                         }
1028                 }
1029 # check of hardware specific defines
1030                 if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@) {
1031                         CHK("architecture specific defines should be avoided\n" .  $herecurr);
1032                 }
1033
1034 # check the location of the inline attribute, that it is between
1035 # storage class and type.
1036                 if ($line =~ /$Type\s+(?:inline|__always_inline)\b/ ||
1037                     $line =~ /\b(?:inline|always_inline)\s+$Storage/) {
1038                         ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
1039                 }
1040
1041 # check for new externs in .c files.
1042                 if ($line =~ /^.\s*extern\s/ && ($realfile =~ /\.c$/)) {
1043                         WARN("externs should be avoided in .c files\n" .  $herecurr);
1044                 }
1045
1046 # checks for new __setup's
1047                 if ($rawline =~ /\b__setup\("([^"]*)"/) {
1048                         my $name = $1;
1049
1050                         if (!grep(/$name/, @setup_docs)) {
1051                                 CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
1052                         }
1053                 }
1054         }
1055
1056         if ($chk_patch && !$is_patch) {
1057                 ERROR("Does not appear to be a unified-diff format patch\n");
1058         }
1059         if ($is_patch && $chk_signoff && $signoff == 0) {
1060                 ERROR("Missing Signed-off-by: line(s)\n");
1061         }
1062
1063         if ($clean == 0 && ($chk_patch || $is_patch)) {
1064                 print report_dump();
1065         }
1066         if ($clean == 1 && $quiet == 0) {
1067                 print "Your patch has no obvious style problems and is ready for submission.\n"
1068         }
1069         if ($clean == 0 && $quiet == 0) {
1070                 print "Your patch has style problems, please review.  If any of these errors\n";
1071                 print "are false positives report them to the maintainer, see\n";
1072                 print "CHECKPATCH in MAINTAINERS.\n";
1073         }
1074         return $clean;
1075 }