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 = '0.12';
  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 my $emacs = 0;
  22 my $terse = 0;
  23 my $file = 0;
  24 my $check = 0;
  25 my $summary = 1;
  26 my $mailback = 0;
  27 my $root;
  28 GetOptions(
  29         'q|quiet+'      => \$quiet,
  30         'tree!'         => \$tree,
  31         'signoff!'      => \$chk_signoff,
  32         'patch!'        => \$chk_patch,
  33         'test-type!'    => \$tst_type,
  34         'emacs!'        => \$emacs,
  35         'terse!'        => \$terse,
  36         'file!'         => \$file,
  37         'subjective!'   => \$check,
  38         'strict!'       => \$check,
  39         'root=s'        => \$root,
  40         'summary!'      => \$summary,
  41         'mailback!'     => \$mailback,
  42 ) or exit;
  43
  44 my $exit = 0;
  45
  46 if ($#ARGV < 0) {
  47         print "usage: $P [options] patchfile\n";
  48         print "version: $V\n";
  49         print "options: -q           => quiet\n";
  50         print "         --no-tree    => run without a kernel tree\n";
  51         print "         --terse      => one line per report\n";
  52         print "         --emacs      => emacs compile window format\n";
  53         print "         --file       => check a source file\n";
  54         print "         --strict     => enable more subjective tests\n";
  55         print "         --root       => path to the kernel tree root\n";
  56         exit(1);
  57 }
  58
  59 if ($terse) {
  60         $emacs = 1;
  61         $quiet++;
  62 }
  63
  64 if ($tree) {
  65         if (defined $root) {
  66                 if (!top_of_kernel_tree($root)) {
  67                         die "$P: $root: --root does not point at a valid tree\n";
  68                 }
  69         } else {
  70                 if (top_of_kernel_tree('.')) {
  71                         $root = '.';
  72                 } elsif ($0 =~ m@(.*)/scripts/[^/]*$@ &&
  73                                                 top_of_kernel_tree($1)) {
  74                         $root = $1;
  75                 }
  76         }
  77
  78         if (!defined $root) {
  79                 print "Must be run from the top-level dir. of a kernel tree\n";
  80                 exit(2);
  81         }
  82 }
  83
  84 my $emitted_corrupt = 0;
  85
  86 our $Ident       = qr{[A-Za-z_][A-Za-z\d_]*};
  87 our $Storage    = qr{extern|static|asmlinkage};
  88 our $Sparse     = qr{
  89                         __user|
  90                         __kernel|
  91                         __force|
  92                         __iomem|
  93                         __must_check|
  94                         __init_refok|
  95                         __kprobes|
  96                         fastcall
  97                 }x;
  98 our $Attribute  = qr{
  99                         const|
 100                         __read_mostly|
 101                         __kprobes|
 102                         __(?:mem|cpu|dev|)(?:initdata|init)
 103                   }x;
 104 our $Inline     = qr{inline|__always_inline|noinline};
 105 our $Member     = qr{->$Ident|\.$Ident|\[[^]]*\]};
 106 our $Lval       = qr{$Ident(?:$Member)*};
 107
 108 our $Constant   = qr{(?:[0-9]+|0x[0-9a-fA-F]+)[UL]*};
 109 our $Assignment = qr{(?:\*\=|/=|%=|\+=|-=|<<=|>>=|&=|\^=|\|=|=)};
 110 our $Operators  = qr{
 111                         <=|>=|==|!=|
 112                         =>|->|<<|>>|<|>|!|~|
 113                         &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/
 114                   }x;
 115
 116 our $NonptrType;
 117 our $Type;
 118 our $Declare;
 119
 120 our @typeList = (
 121         qr{void},
 122         qr{char},
 123         qr{short},
 124         qr{int},
 125         qr{long},
 126         qr{unsigned},
 127         qr{float},
 128         qr{double},
 129         qr{bool},
 130         qr{long\s+int},
 131         qr{long\s+long},
 132         qr{long\s+long\s+int},
 133         qr{(?:__)?(?:u|s|be|le)(?:8|16|32|64)},
 134         qr{struct\s+$Ident},
 135         qr{union\s+$Ident},
 136         qr{enum\s+$Ident},
 137         qr{${Ident}_t},
 138         qr{${Ident}_handler},
 139         qr{${Ident}_handler_fn},
 140 );
 141
 142 sub build_types {
 143         my $all = "(?:  \n" . join("|\n  ", @typeList) . "\n)";
 144         $NonptrType     = qr{
 145                         \b
 146                         (?:const\s+)?
 147                         (?:unsigned\s+)?
 148                         $all
 149                         (?:\s+$Sparse|\s+const)*
 150                         \b
 151                   }x;
 152         $Type   = qr{
 153                         \b$NonptrType\b
 154                         (?:\s*\*+\s*const|\s*\*+|(?:\s*\[\s*\])+)?
 155                         (?:\s+$Sparse|\s+$Attribute)*
 156                   }x;
 157         $Declare        = qr{(?:$Storage\s+)?$Type};
 158 }
 159 build_types();
 160
 161 $chk_signoff = 0 if ($file);
 162
 163 my @dep_includes = ();
 164 my @dep_functions = ();
 165 my $removal = "Documentation/feature-removal-schedule.txt";
 166 if ($tree && -f "$root/$removal") {
 167         open(REMOVE, "<$root/$removal") ||
 168                                 die "$P: $removal: open failed - $!\n";
 169         while (<REMOVE>) {
 170                 if (/^Check:\s+(.*\S)/) {
 171                         for my $entry (split(/[, ]+/, $1)) {
 172                                 if ($entry =~ m@include/(.*)@) {
 173                                         push(@dep_includes, $1);
 174
 175                                 } elsif ($entry !~ m@/@) {
 176                                         push(@dep_functions, $entry);
 177                                 }
 178                         }
 179                 }
 180         }
 181 }
 182
 183 my @rawlines = ();
 184 for my $filename (@ARGV) {
 185         if ($file) {
 186                 open(FILE, "diff -u /dev/null $filename|") ||
 187                         die "$P: $filename: diff failed - $!\n";
 188         } else {
 189                 open(FILE, "<$filename") ||
 190                         die "$P: $filename: open failed - $!\n";
 191         }
 192         while (<FILE>) {
 193                 chomp;
 194                 push(@rawlines, $_);
 195         }
 196         close(FILE);
 197         if (!process($filename, @rawlines)) {
 198                 $exit = 1;
 199         }
 200         @rawlines = ();
 201 }
 202
 203 exit($exit);
 204
 205 sub top_of_kernel_tree {
 206         my ($root) = @_;
 207
 208         my @tree_check = (
 209                 "COPYING", "CREDITS", "Kbuild", "MAINTAINERS", "Makefile",
 210                 "README", "Documentation", "arch", "include", "drivers",
 211                 "fs", "init", "ipc", "kernel", "lib", "scripts",
 212         );
 213
 214         foreach my $check (@tree_check) {
 215                 if (! -e $root . '/' . $check) {
 216                         return 0;
 217                 }
 218         }
 219         return 1;
 220 }
 221
 222 sub expand_tabs {
 223         my ($str) = @_;
 224
 225         my $res = '';
 226         my $n = 0;
 227         for my $c (split(//, $str)) {
 228                 if ($c eq "\t") {
 229                         $res .= ' ';
 230                         $n++;
 231                         for (; ($n % 8) != 0; $n++) {
 232                                 $res .= ' ';
 233                         }
 234                         next;
 235                 }
 236                 $res .= $c;
 237                 $n++;
 238         }
 239
 240         return $res;
 241 }
 242 sub copy_spacing {
 243         my ($str) = @_;
 244
 245         my $res = '';
 246         for my $c (split(//, $str)) {
 247                 if ($c eq "\t") {
 248                         $res .= $c;
 249                 } else {
 250                         $res .= ' ';
 251                 }
 252         }
 253
 254         return $res;
 255 }
 256
 257 sub line_stats {
 258         my ($line) = @_;
 259
 260         # Drop the diff line leader and expand tabs
 261         $line =~ s/^.//;
 262         $line = expand_tabs($line);
 263
 264         # Pick the indent from the front of the line.
 265         my ($white) = ($line =~ /^(\s*)/);
 266
 267         return (length($line), length($white));
 268 }
 269
 270 sub sanitise_line {
 271         my ($line) = @_;
 272
 273         my $res = '';
 274         my $l = '';
 275
 276         my $quote = '';
 277
 278         foreach my $c (split(//, $line)) {
 279                 if ($l ne "\\" && ($c eq "'" || $c eq '"')) {
 280                         if ($quote eq '') {
 281                                 $quote = $c;
 282                                 $res .= $c;
 283                                 $l = $c;
 284                                 next;
 285                         } elsif ($quote eq $c) {
 286                                 $quote = '';
 287                         }
 288                 }
 289                 if ($quote && $c ne "\t") {
 290                         $res .= "X";
 291                 } else {
 292                         $res .= $c;
 293                 }
 294
 295                 $l = $c;
 296         }
 297
 298         return $res;
 299 }
 300
 301 sub ctx_statement_block {
 302         my ($linenr, $remain, $off) = @_;
 303         my $line = $linenr - 1;
 304         my $blk = '';
 305         my $soff = $off;
 306         my $coff = $off - 1;
 307
 308         my $type = '';
 309         my $level = 0;
 310         my $c;
 311         my $len = 0;
 312         while (1) {
 313                 #warn "CSB: blk<$blk>\n";
 314                 # If we are about to drop off the end, pull in more
 315                 # context.
 316                 if ($off >= $len) {
 317                         for (; $remain > 0; $line++) {
 318                                 next if ($rawlines[$line] =~ /^-/);
 319                                 $remain--;
 320                                 $blk .= sanitise_line($rawlines[$line]) . "\n";
 321                                 $len = length($blk);
 322                                 $line++;
 323                                 last;
 324                         }
 325                         # Bail if there is no further context.
 326                         #warn "CSB: blk<$blk> off<$off> len<$len>\n";
 327                         if ($off == $len) {
 328                                 last;
 329                         }
 330                 }
 331                 $c = substr($blk, $off, 1);
 332
 333                 #warn "CSB: c<$c> type<$type> level<$level>\n";
 334                 # Statement ends at the ';' or a close '}' at the
 335                 # outermost level.
 336                 if ($level == 0 && $c eq ';') {
 337                         last;
 338                 }
 339
 340                 if (($type eq '' || $type eq '(') && $c eq '(') {
 341                         $level++;
 342                         $type = '(';
 343                 }
 344                 if ($type eq '(' && $c eq ')') {
 345                         $level--;
 346                         $type = ($level != 0)? '(' : '';
 347
 348                         if ($level == 0 && $coff < $soff) {
 349                                 $coff = $off;
 350                         }
 351                 }
 352                 if (($type eq '' || $type eq '{') && $c eq '{') {
 353                         $level++;
 354                         $type = '{';
 355                 }
 356                 if ($type eq '{' && $c eq '}') {
 357                         $level--;
 358                         $type = ($level != 0)? '{' : '';
 359
 360                         if ($level == 0) {
 361                                 last;
 362                         }
 363                 }
 364                 $off++;
 365         }
 366
 367         my $statement = substr($blk, $soff, $off - $soff + 1);
 368         my $condition = substr($blk, $soff, $coff - $soff + 1);
 369
 370         #warn "STATEMENT<$statement>\n";
 371         #warn "CONDITION<$condition>\n";
 372
 373         return ($statement, $condition);
 374 }
 375
 376 sub ctx_block_get {
 377         my ($linenr, $remain, $outer, $open, $close, $off) = @_;
 378         my $line;
 379         my $start = $linenr - 1;
 380         my $blk = '';
 381         my @o;
 382         my @c;
 383         my @res = ();
 384
 385         my $level = 0;
 386         for ($line = $start; $remain > 0; $line++) {
 387                 next if ($rawlines[$line] =~ /^-/);
 388                 $remain--;
 389
 390                 $blk .= $rawlines[$line];
 391                 foreach my $c (split(//, $rawlines[$line])) {
 392                         ##print "C<$c>L<$level><$open$close>O<$off>\n";
 393                         if ($off > 0) {
 394                                 $off--;
 395                                 next;
 396                         }
 397
 398                         if ($c eq $close && $level > 0) {
 399                                 $level--;
 400                                 last if ($level == 0);
 401                         } elsif ($c eq $open) {
 402                                 $level++;
 403                         }
 404                 }
 405
 406                 if (!$outer || $level <= 1) {
 407                         push(@res, $rawlines[$line]);
 408                 }
 409
 410                 last if ($level == 0);
 411         }
 412
 413         return ($level, @res);
 414 }
 415 sub ctx_block_outer {
 416         my ($linenr, $remain) = @_;
 417
 418         my ($level, @r) = ctx_block_get($linenr, $remain, 1, '{', '}', 0);
 419         return @r;
 420 }
 421 sub ctx_block {
 422         my ($linenr, $remain) = @_;
 423
 424         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 425         return @r;
 426 }
 427 sub ctx_statement {
 428         my ($linenr, $remain, $off) = @_;
 429
 430         my ($level, @r) = ctx_block_get($linenr, $remain, 0, '(', ')', $off);
 431         return @r;
 432 }
 433 sub ctx_block_level {
 434         my ($linenr, $remain) = @_;
 435
 436         return ctx_block_get($linenr, $remain, 0, '{', '}', 0);
 437 }
 438 sub ctx_statement_level {
 439         my ($linenr, $remain, $off) = @_;
 440
 441         return ctx_block_get($linenr, $remain, 0, '(', ')', $off);
 442 }
 443
 444 sub ctx_locate_comment {
 445         my ($first_line, $end_line) = @_;
 446
 447         # Catch a comment on the end of the line itself.
 448         my ($current_comment) = ($rawlines[$end_line - 1] =~ m@.*(/\*.*\*/)\s*$@);
 449         return $current_comment if (defined $current_comment);
 450
 451         # Look through the context and try and figure out if there is a
 452         # comment.
 453         my $in_comment = 0;
 454         $current_comment = '';
 455         for (my $linenr = $first_line; $linenr < $end_line; $linenr++) {
 456                 my $line = $rawlines[$linenr - 1];
 457                 #warn "           $line\n";
 458                 if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 459                         $in_comment = 1;
 460                 }
 461                 if ($line =~ m@/\*@) {
 462                         $in_comment = 1;
 463                 }
 464                 if (!$in_comment && $current_comment ne '') {
 465                         $current_comment = '';
 466                 }
 467                 $current_comment .= $line . "\n" if ($in_comment);
 468                 if ($line =~ m@\*/@) {
 469                         $in_comment = 0;
 470                 }
 471         }
 472
 473         chomp($current_comment);
 474         return($current_comment);
 475 }
 476 sub ctx_has_comment {
 477         my ($first_line, $end_line) = @_;
 478         my $cmt = ctx_locate_comment($first_line, $end_line);
 479
 480         ##print "LINE: $rawlines[$end_line - 1 ]\n";
 481         ##print "CMMT: $cmt\n";
 482
 483         return ($cmt ne '');
 484 }
 485
 486 sub cat_vet {
 487         my ($vet) = @_;
 488         my ($res, $coded);
 489
 490         $res = '';
 491         while ($vet =~ /([^[:cntrl:]]*)([[:cntrl:]]|$)/g) {
 492                 $res .= $1;
 493                 if ($2 ne '') {
 494                         $coded = sprintf("^%c", unpack('C', $2) + 64);
 495                         $res .= $coded;
 496                 }
 497         }
 498         $res =~ s/$/\$/;
 499
 500         return $res;
 501 }
 502
 503 sub annotate_values {
 504         my ($stream, $type) = @_;
 505
 506         my $res;
 507         my $cur = $stream;
 508
 509         my $debug = 0;
 510
 511         print "$stream\n" if ($debug);
 512
 513         ##my $type = 'N';
 514         my $pos = 0;
 515         my $preprocessor = 0;
 516         my $paren = 0;
 517         my @paren_type;
 518
 519         while (length($cur)) {
 520                 print " <$type> " if ($debug);
 521                 if ($cur =~ /^(\s+)/o) {
 522                         print "WS($1)\n" if ($debug);
 523                         if ($1 =~ /\n/ && $preprocessor) {
 524                                 $preprocessor = 0;
 525                                 $type = 'N';
 526                         }
 527
 528                 } elsif ($cur =~ /^($Type)/) {
 529                         print "DECLARE($1)\n" if ($debug);
 530                         $type = 'T';
 531
 532                 } elsif ($cur =~ /^(#\s*define\s*$Ident)(\(?)/o) {
 533                         print "DEFINE($1)\n" if ($debug);
 534                         $preprocessor = 1;
 535                         $paren_type[$paren] = 'N';
 536
 537                 } elsif ($cur =~ /^(#\s*(?:ifdef|ifndef|if|else|endif))/o) {
 538                         print "PRE($1)\n" if ($debug);
 539                         $preprocessor = 1;
 540                         $type = 'N';
 541
 542                 } elsif ($cur =~ /^(\\\n)/o) {
 543                         print "PRECONT($1)\n" if ($debug);
 544
 545                 } elsif ($cur =~ /^(sizeof)\s*(\()?/o) {
 546                         print "SIZEOF($1)\n" if ($debug);
 547                         if (defined $2) {
 548                                 $paren_type[$paren] = 'V';
 549                         }
 550                         $type = 'N';
 551
 552                 } elsif ($cur =~ /^(if|while|typeof|for)\b/o) {
 553                         print "COND($1)\n" if ($debug);
 554                         $paren_type[$paren] = 'N';
 555                         $type = 'N';
 556
 557                 } elsif ($cur =~/^(return|case|else)/o) {
 558                         print "KEYWORD($1)\n" if ($debug);
 559                         $type = 'N';
 560
 561                 } elsif ($cur =~ /^(\()/o) {
 562                         print "PAREN('$1')\n" if ($debug);
 563                         $paren++;
 564                         $type = 'N';
 565
 566                 } elsif ($cur =~ /^(\))/o) {
 567                         $paren-- if ($paren > 0);
 568                         if (defined $paren_type[$paren]) {
 569                                 $type = $paren_type[$paren];
 570                                 undef $paren_type[$paren];
 571                                 print "PAREN('$1') -> $type\n" if ($debug);
 572                         } else {
 573                                 print "PAREN('$1')\n" if ($debug);
 574                         }
 575
 576                 } elsif ($cur =~ /^($Ident)\(/o) {
 577                         print "FUNC($1)\n" if ($debug);
 578                         $paren_type[$paren] = 'V';
 579
 580                 } elsif ($cur =~ /^($Ident|$Constant)/o) {
 581                         print "IDENT($1)\n" if ($debug);
 582                         $type = 'V';
 583
 584                 } elsif ($cur =~ /^($Assignment)/o) {
 585                         print "ASSIGN($1)\n" if ($debug);
 586                         $type = 'N';
 587
 588                 } elsif ($cur =~ /^(;|{|}|\?|:|\[)/o) {
 589                         print "END($1)\n" if ($debug);
 590                         $type = 'N';
 591
 592                 } elsif ($cur =~ /^($Operators)/o) {
 593                         print "OP($1)\n" if ($debug);
 594                         if ($1 ne '++' && $1 ne '--') {
 595                                 $type = 'N';
 596                         }
 597
 598                 } elsif ($cur =~ /(^.)/o) {
 599                         print "C($1)\n" if ($debug);
 600                 }
 601                 if (defined $1) {
 602                         $cur = substr($cur, length($1));
 603                         $res .= $type x length($1);
 604                 }
 605         }
 606
 607         return $res;
 608 }
 609
 610 sub possible {
 611         my ($possible) = @_;
 612
 613         #print "CHECK<$possible>\n";
 614         if ($possible !~ /^(?:$Storage|$Type|DEFINE_\S+)$/ &&
 615             $possible ne 'goto' && $possible ne 'return' &&
 616             $possible ne 'struct' && $possible ne 'enum' &&
 617             $possible ne 'case' && $possible ne 'else' &&
 618             $possible ne 'typedef') {
 619                 #print "POSSIBLE<$possible>\n";
 620                 push(@typeList, $possible);
 621                 build_types();
 622         }
 623 }
 624
 625 my $prefix = '';
 626
 627 my @report = ();
 628 sub report {
 629         my $line = $prefix . $_[0];
 630
 631         $line = (split('\n', $line))[0] . "\n" if ($terse);
 632
 633         push(@report, $line);
 634 }
 635 sub report_dump {
 636         @report;
 637 }
 638 sub ERROR {
 639         report("ERROR: $_[0]\n");
 640         our $clean = 0;
 641         our $cnt_error++;
 642 }
 643 sub WARN {
 644         report("WARNING: $_[0]\n");
 645         our $clean = 0;
 646         our $cnt_warn++;
 647 }
 648 sub CHK {
 649         if ($check) {
 650                 report("CHECK: $_[0]\n");
 651                 our $clean = 0;
 652                 our $cnt_chk++;
 653         }
 654 }
 655
 656 sub process {
 657         my $filename = shift;
 658         my @lines = @_;
 659
 660         my $linenr=0;
 661         my $prevline="";
 662         my $stashline="";
 663
 664         my $length;
 665         my $indent;
 666         my $previndent=0;
 667         my $stashindent=0;
 668
 669         our $clean = 1;
 670         my $signoff = 0;
 671         my $is_patch = 0;
 672
 673         our $cnt_lines = 0;
 674         our $cnt_error = 0;
 675         our $cnt_warn = 0;
 676         our $cnt_chk = 0;
 677
 678         # Trace the real file/line as we go.
 679         my $realfile = '';
 680         my $realline = 0;
 681         my $realcnt = 0;
 682         my $here = '';
 683         my $in_comment = 0;
 684         my $first_line = 0;
 685
 686         my $prev_values = 'N';
 687
 688         # Pre-scan the patch looking for any __setup documentation.
 689         my @setup_docs = ();
 690         my $setup_docs = 0;
 691         foreach my $line (@lines) {
 692                 if ($line=~/^\+\+\+\s+(\S+)/) {
 693                         $setup_docs = 0;
 694                         if ($1 =~ m@Documentation/kernel-parameters.txt$@) {
 695                                 $setup_docs = 1;
 696                         }
 697                         next;
 698                 }
 699
 700                 if ($setup_docs && $line =~ /^\+/) {
 701                         push(@setup_docs, $line);
 702                 }
 703         }
 704
 705         $prefix = '';
 706
 707         foreach my $line (@lines) {
 708                 $linenr++;
 709
 710                 my $rawline = $line;
 711
 712
 713 #extract the filename as it passes
 714                 if ($line=~/^\+\+\+\s+(\S+)/) {
 715                         $realfile=$1;
 716                         $realfile =~ s@^[^/]*/@@;
 717                         $in_comment = 0;
 718                         next;
 719                 }
 720 #extract the line range in the file after the patch is applied
 721                 if ($line=~/^\@\@ -\d+(?:,\d+)? \+(\d+)(,(\d+))? \@\@/) {
 722                         $is_patch = 1;
 723                         $first_line = $linenr + 1;
 724                         $in_comment = 0;
 725                         $realline=$1-1;
 726                         if (defined $2) {
 727                                 $realcnt=$3+1;
 728                         } else {
 729                                 $realcnt=1+1;
 730                         }
 731                         $prev_values = 'N';
 732                         next;
 733                 }
 734
 735 # track the line number as we move through the hunk, note that
 736 # new versions of GNU diff omit the leading space on completely
 737 # blank context lines so we need to count that too.
 738                 if ($line =~ /^( |\+|$)/) {
 739                         $realline++;
 740                         $realcnt-- if ($realcnt != 0);
 741
 742                         # Guestimate if this is a continuing comment.  Run
 743                         # the context looking for a comment "edge".  If this
 744                         # edge is a close comment then we must be in a comment
 745                         # at context start.
 746                         if ($linenr == $first_line) {
 747                                 my $edge;
 748                                 for (my $ln = $first_line; $ln < ($linenr + $realcnt); $ln++) {
 749                                         ($edge) = ($lines[$ln - 1] =~ m@(/\*|\*/)@);
 750                                         last if (defined $edge);
 751                                 }
 752                                 if (defined $edge && $edge eq '*/') {
 753                                         $in_comment = 1;
 754                                 }
 755                         }
 756
 757                         # Guestimate if this is a continuing comment.  If this
 758                         # is the start of a diff block and this line starts
 759                         # ' *' then it is very likely a comment.
 760                         if ($linenr == $first_line and $line =~ m@^.\s*\*@) {
 761                                 $in_comment = 1;
 762                         }
 763
 764                         # Find the last comment edge on _this_ line.
 765                         while (($line =~ m@(/\*|\*/)@g)) {
 766                                 if ($1 eq '/*') {
 767                                         $in_comment = 1;
 768                                 } else {
 769                                         $in_comment = 0;
 770                                 }
 771                         }
 772
 773                         # Measure the line length and indent.
 774                         ($length, $indent) = line_stats($line);
 775
 776                         # Track the previous line.
 777                         ($prevline, $stashline) = ($stashline, $line);
 778                         ($previndent, $stashindent) = ($stashindent, $indent);
 779
 780                 } elsif ($realcnt == 1) {
 781                         $realcnt--;
 782                 }
 783
 784 #make up the handle for any error we report on this line
 785                 $here = "#$linenr: " if (!$file);
 786                 $here = "#$realline: " if ($file);
 787                 $here .= "FILE: $realfile:$realline:" if ($realcnt != 0);
 788
 789                 my $hereline = "$here\n$line\n";
 790                 my $herecurr = "$here\n$line\n";
 791                 my $hereprev = "$here\n$prevline\n$line\n";
 792
 793                 $prefix = "$filename:$realline: " if ($emacs && $file);
 794                 $prefix = "$filename:$linenr: " if ($emacs && !$file);
 795                 $cnt_lines++ if ($realcnt != 0);
 796
 797 #check the patch for a signoff:
 798                 if ($line =~ /^\s*signed-off-by:/i) {
 799                         # This is a signoff, if ugly, so do not double report.
 800                         $signoff++;
 801                         if (!($line =~ /^\s*Signed-off-by:/)) {
 802                                 WARN("Signed-off-by: is the preferred form\n" .
 803                                         $herecurr);
 804                         }
 805                         if ($line =~ /^\s*signed-off-by:\S/i) {
 806                                 WARN("need space after Signed-off-by:\n" .
 807                                         $herecurr);
 808                         }
 809                 }
 810
 811 # Check for wrappage within a valid hunk of the file
 812                 if ($realcnt != 0 && $line !~ m{^(?:\+|-| |\\ No newline|$)}) {
 813                         ERROR("patch seems to be corrupt (line wrapped?)\n" .
 814                                 $herecurr) if (!$emitted_corrupt++);
 815                 }
 816
 817 # UTF-8 regex found at http://www.w3.org/International/questions/qa-forms-utf-8.en.php
 818                 if (($realfile =~ /^$/ || $line =~ /^\+/) &&
 819                      !($line =~ m/^(
 820                                 [\x09\x0A\x0D\x20-\x7E]              # ASCII
 821                                 | [\xC2-\xDF][\x80-\xBF]             # non-overlong 2-byte
 822                                 |  \xE0[\xA0-\xBF][\x80-\xBF]        # excluding overlongs
 823                                 | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}  # straight 3-byte
 824                                 |  \xED[\x80-\x9F][\x80-\xBF]        # excluding surrogates
 825                                 |  \xF0[\x90-\xBF][\x80-\xBF]{2}     # planes 1-3
 826                                 | [\xF1-\xF3][\x80-\xBF]{3}          # planes 4-15
 827                                 |  \xF4[\x80-\x8F][\x80-\xBF]{2}     # plane 16
 828                                 )*$/x )) {
 829                         ERROR("Invalid UTF-8\n" . $herecurr);
 830                 }
 831
 832 #ignore lines being removed
 833                 if ($line=~/^-/) {next;}
 834
 835 # check we are in a valid source file if not then ignore this hunk
 836                 next if ($realfile !~ /\.(h|c|s|S|pl|sh)$/);
 837
 838 #trailing whitespace
 839                 if ($line =~ /^\+.*\015/) {
 840                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 841                         ERROR("DOS line endings\n" . $herevet);
 842
 843                 } elsif ($line =~ /^\+.*\S\s+$/ || $line =~ /^\+\s+$/) {
 844                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 845                         ERROR("trailing whitespace\n" . $herevet);
 846                 }
 847 #80 column limit
 848                 if ($line =~ /^\+/ && !($prevline=~/\/\*\*/) && $length > 80) {
 849                         WARN("line over 80 characters\n" . $herecurr);
 850                 }
 851
 852 # check for adding lines without a newline.
 853                 if ($line =~ /^\+/ && defined $lines[$linenr] && $lines[$linenr] =~ /^\\ No newline at end of file/) {
 854                         WARN("adding a line without newline at end of file\n" . $herecurr);
 855                 }
 856
 857 # check we are in a valid source file *.[hc] if not then ignore this hunk
 858                 next if ($realfile !~ /\.[hc]$/);
 859
 860 # at the beginning of a line any tabs must come first and anything
 861 # more than 8 must use tabs.
 862                 if ($line=~/^\+\s* \t\s*\S/ or $line=~/^\+\s*        \s*/) {
 863                         my $herevet = "$here\n" . cat_vet($line) . "\n";
 864                         ERROR("use tabs not spaces\n" . $herevet);
 865                 }
 866
 867 # Remove comments from the line before processing.
 868                 my $comment_edge = ($line =~ s@/\*.*\*/@@g) +
 869                                    ($line =~ s@/\*.*@@) +
 870                                    ($line =~ s@^(.).*\*/@$1@);
 871
 872 # The rest of our checks refer specifically to C style
 873 # only apply those _outside_ comments.  Only skip
 874 # lines in the middle of comments.
 875                 next if (!$comment_edge && $in_comment);
 876
 877 # Standardise the strings and chars within the input to simplify matching.
 878                 $line = sanitise_line($line);
 879
 880 # Check for potential 'bare' types
 881                 if ($realcnt &&
 882                     $line !~ /$Ident:\s*$/ &&
 883                     ($line =~ /^.\s*$Ident\s*\(\*+\s*$Ident\)\s*\(/ ||
 884                      $line !~ /^.\s*$Ident\s*\(/)) {
 885                         # definitions in global scope can only start with types
 886                         if ($line =~ /^.(?:$Storage\s+)?(?:$Inline\s+)?(?:const\s+)?($Ident)\b/) {
 887                                 possible($1);
 888
 889                         # declarations always start with types
 890                         } elsif ($prev_values eq 'N' && $line =~ /^.\s*(?:$Storage\s+)?($Ident)\b\s*\**\s*$Ident\s*(?:;|=)/) {
 891                                 possible($1);
 892
 893                         # any (foo ... *) is a pointer cast, and foo is a type
 894                         } elsif ($line =~ /\(($Ident)(?:\s+$Sparse)*\s*\*+\s*\)/) {
 895                                 possible($1);
 896                         }
 897
 898                         # Check for any sort of function declaration.
 899                         # int foo(something bar, other baz);
 900                         # void (*store_gdt)(x86_descr_ptr *);
 901                         if ($prev_values eq 'N' && $line =~ /^(.(?:(?:$Storage|$Inline)\s*)*\s*$Type\s*(?:\b$Ident|\(\*\s*$Ident\))\s*)\(/) {
 902                                 my ($name_len) = length($1);
 903                                 my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, $name_len);
 904                                 my $ctx = join("\n", @ctx);
 905
 906                                 $ctx =~ s/\n.//;
 907                                 substr($ctx, 0, $name_len + 1) = '';
 908                                 $ctx =~ s/\)[^\)]*$//;
 909                                 for my $arg (split(/\s*,\s*/, $ctx)) {
 910                                         if ($arg =~ /^(?:const\s+)?($Ident)(?:\s+$Sparse)*\s*\**\s*(:?\b$Ident)?$/ || $arg =~ /^($Ident)$/) {
 911
 912                                                 possible($1);
 913                                         }
 914                                 }
 915                         }
 916
 917                 }
 918
 919 #
 920 # Checks which may be anchored in the context.
 921 #
 922
 923 # Check for switch () and associated case and default
 924 # statements should be at the same indent.
 925                 if ($line=~/\bswitch\s*\(.*\)/) {
 926                         my $err = '';
 927                         my $sep = '';
 928                         my @ctx = ctx_block_outer($linenr, $realcnt);
 929                         shift(@ctx);
 930                         for my $ctx (@ctx) {
 931                                 my ($clen, $cindent) = line_stats($ctx);
 932                                 if ($ctx =~ /^\+\s*(case\s+|default:)/ &&
 933                                                         $indent != $cindent) {
 934                                         $err .= "$sep$ctx\n";
 935                                         $sep = '';
 936                                 } else {
 937                                         $sep = "[...]\n";
 938                                 }
 939                         }
 940                         if ($err ne '') {
 941                                 ERROR("switch and case should be at the same indent\n$hereline$err");
 942                         }
 943                 }
 944
 945 # if/while/etc brace do not go on next line, unless defining a do while loop,
 946 # or if that brace on the next line is for something else
 947                 if ($line =~ /\b(?:(if|while|for|switch)\s*\(|do\b|else\b)/ && $line !~ /^.#/) {
 948                         my ($level, @ctx) = ctx_statement_level($linenr, $realcnt, 0);
 949                         my $ctx_ln = $linenr + $#ctx + 1;
 950                         my $ctx_cnt = $realcnt - $#ctx - 1;
 951                         my $ctx = join("\n", @ctx);
 952
 953                         # Skip over any removed lines in the context following statement.
 954                         while ($ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^-/) {
 955                                 $ctx_ln++;
 956                                 $ctx_cnt--;
 957                         }
 958                         ##warn "line<$line>\nctx<$ctx>\nnext<$lines[$ctx_ln - 1]>";
 959
 960                         if ($ctx !~ /{\s*/ && $ctx_cnt > 0 && $lines[$ctx_ln - 1] =~ /^\+\s*{/) {
 961                                 ERROR("That open brace { should be on the previous line\n" .
 962                                         "$here\n$ctx\n$lines[$ctx_ln - 1]");
 963                         }
 964                         if ($level == 0 && $ctx =~ /\)\s*\;\s*$/ && defined $lines[$ctx_ln - 1]) {
 965                                 my ($nlength, $nindent) = line_stats($lines[$ctx_ln - 1]);
 966                                 if ($nindent > $indent) {
 967                                         WARN("Trailing semicolon indicates no statements, indent implies otherwise\n" .
 968                                                 "$here\n$ctx\n$lines[$ctx_ln - 1]");
 969                                 }
 970                         }
 971                 }
 972
 973                 # Track the 'values' across context and added lines.
 974                 my $opline = $line; $opline =~ s/^./ /;
 975                 my $curr_values = annotate_values($opline . "\n", $prev_values);
 976                 $curr_values = $prev_values . $curr_values;
 977                 #warn "--> $opline\n";
 978                 #warn "--> $curr_values ($prev_values)\n";
 979                 $prev_values = substr($curr_values, -1);
 980
 981 #ignore lines not being added
 982                 if ($line=~/^[^\+]/) {next;}
 983
 984 # TEST: allow direct testing of the type matcher.
 985                 if ($tst_type && $line =~ /^.$Declare$/) {
 986                         ERROR("TEST: is type $Declare\n" . $herecurr);
 987                         next;
 988                 }
 989
 990 # check for initialisation to aggregates open brace on the next line
 991                 if ($prevline =~ /$Declare\s*$Ident\s*=\s*$/ &&
 992                     $line =~ /^.\s*{/) {
 993                         ERROR("That open brace { should be on the previous line\n" . $hereprev);
 994                 }
 995
 996 #
 997 # Checks which are anchored on the added line.
 998 #
 999
1000 # check for malformed paths in #include statements (uses RAW line)
1001                 if ($rawline =~ m{^.#\s*include\s+[<"](.*)[">]}) {
1002                         my $path = $1;
1003                         if ($path =~ m{//}) {
1004                                 ERROR("malformed #include filename\n" .
1005                                         $herecurr);
1006                         }
1007                         # Sanitise this special form of string.
1008                         $path = 'X' x length($path);
1009                         $line =~ s{\<.*\>}{<$path>};
1010                 }
1011
1012 # no C99 // comments
1013                 if ($line =~ m{//}) {
1014                         ERROR("do not use C99 // comments\n" . $herecurr);
1015                 }
1016                 # Remove C99 comments.
1017                 $line =~ s@//.*@@;
1018                 $opline =~ s@//.*@@;
1019
1020 #EXPORT_SYMBOL should immediately follow its function closing }.
1021                 if (($line =~ /EXPORT_SYMBOL.*\((.*)\)/) ||
1022                     ($line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
1023                         my $name = $1;
1024                         if (($prevline !~ /^}/) &&
1025                            ($prevline !~ /^\+}/) &&
1026                            ($prevline !~ /^ }/) &&
1027                            ($prevline !~ /\b\Q$name\E(?:\s+$Attribute)?\s*(?:;|=)/)) {
1028                                 WARN("EXPORT_SYMBOL(foo); should immediately follow its function/variable\n" . $herecurr);
1029                         }
1030                 }
1031
1032 # check for external initialisers.
1033                 if ($line =~ /^.$Type\s*$Ident\s*=\s*(0|NULL);/) {
1034                         ERROR("do not initialise externals to 0 or NULL\n" .
1035                                 $herecurr);
1036                 }
1037 # check for static initialisers.
1038                 if ($line =~ /\s*static\s.*=\s*(0|NULL);/) {
1039                         ERROR("do not initialise statics to 0 or NULL\n" .
1040                                 $herecurr);
1041                 }
1042
1043 # check for new typedefs, only function parameters and sparse annotations
1044 # make sense.
1045                 if ($line =~ /\btypedef\s/ &&
1046                     $line !~ /\btypedef\s+$Type\s+\(\s*\*?$Ident\s*\)\s*\(/ &&
1047                     $line !~ /\b__bitwise(?:__|)\b/) {
1048                         WARN("do not add new typedefs\n" . $herecurr);
1049                 }
1050
1051 # * goes on variable not on type
1052                 if ($line =~ m{\($NonptrType(\*+)(?:\s+const)?\)}) {
1053                         ERROR("\"(foo$1)\" should be \"(foo $1)\"\n" .
1054                                 $herecurr);
1055
1056                 } elsif ($line =~ m{\($NonptrType\s+(\*+)(?!\s+const)\s+\)}) {
1057                         ERROR("\"(foo $1 )\" should be \"(foo $1)\"\n" .
1058                                 $herecurr);
1059
1060                 } elsif ($line =~ m{$NonptrType(\*+)(?:\s+(?:$Attribute|$Sparse))?\s+[A-Za-z\d_]+}) {
1061                         ERROR("\"foo$1 bar\" should be \"foo $1bar\"\n" .
1062                                 $herecurr);
1063
1064                 } elsif ($line =~ m{$NonptrType\s+(\*+)(?!\s+(?:$Attribute|$Sparse))\s+[A-Za-z\d_]+}) {
1065                         ERROR("\"foo $1 bar\" should be \"foo $1bar\"\n" .
1066                                 $herecurr);
1067                 }
1068
1069 # # no BUG() or BUG_ON()
1070 #               if ($line =~ /\b(BUG|BUG_ON)\b/) {
1071 #                       print "Try to use WARN_ON & Recovery code rather than BUG() or BUG_ON()\n";
1072 #                       print "$herecurr";
1073 #                       $clean = 0;
1074 #               }
1075
1076                 if ($line =~ /\bLINUX_VERSION_CODE\b/) {
1077                         WARN("LINUX_VERSION_CODE should be avoided, code should be for the version to which it is merged" . $herecurr);
1078                 }
1079
1080 # printk should use KERN_* levels.  Note that follow on printk's on the
1081 # same line do not need a level, so we use the current block context
1082 # to try and find and validate the current printk.  In summary the current
1083 # printk includes all preceeding printk's which have no newline on the end.
1084 # we assume the first bad printk is the one to report.
1085                 if ($line =~ /\bprintk\((?!KERN_)\s*"/) {
1086                         my $ok = 0;
1087                         for (my $ln = $linenr - 1; $ln >= $first_line; $ln--) {
1088                                 #print "CHECK<$lines[$ln - 1]\n";
1089                                 # we have a preceeding printk if it ends
1090                                 # with "\n" ignore it, else it is to blame
1091                                 if ($lines[$ln - 1] =~ m{\bprintk\(}) {
1092                                         if ($rawlines[$ln - 1] !~ m{\\n"}) {
1093                                                 $ok = 1;
1094                                         }
1095                                         last;
1096                                 }
1097                         }
1098                         if ($ok == 0) {
1099                                 WARN("printk() should include KERN_ facility level\n" . $herecurr);
1100                         }
1101                 }
1102
1103 # function brace can't be on same line, except for #defines of do while,
1104 # or if closed on same line
1105                 if (($line=~/$Type\s*[A-Za-z\d_]+\(.*\).* {/) and
1106                     !($line=~/\#define.*do\s{/) and !($line=~/}/)) {
1107                         ERROR("open brace '{' following function declarations go on the next line\n" . $herecurr);
1108                 }
1109
1110 # open braces for enum, union and struct go on the same line.
1111                 if ($line =~ /^.\s*{/ &&
1112                     $prevline =~ /^.\s*(?:typedef\s+)?(enum|union|struct)(?:\s+$Ident)?\s*$/) {
1113                         ERROR("open brace '{' following $1 go on the same line\n" . $hereprev);
1114                 }
1115
1116 # check for spaces between functions and their parentheses.
1117                 while ($line =~ /($Ident)\s+\(/g) {
1118                         if ($1 !~ /^(?:if|for|while|switch|return|volatile|__volatile__|__attribute__|format|__extension__|Copyright|case)$/ &&
1119                             $line !~ /$Type\s+\(/ && $line !~ /^.\#\s*define\b/) {
1120                                 WARN("no space between function name and open parenthesis '('\n" . $herecurr);
1121                         }
1122                 }
1123 # Check operator spacing.
1124                 if (!($line=~/\#\s*include/)) {
1125                         my $ops = qr{
1126                                 <<=|>>=|<=|>=|==|!=|
1127                                 \+=|-=|\*=|\/=|%=|\^=|\|=|&=|
1128                                 =>|->|<<|>>|<|>|=|!|~|
1129                                 &&|\|\||,|\^|\+\+|--|&|\||\+|-|\*|\/
1130                         }x;
1131                         my @elements = split(/($ops|;)/, $opline);
1132                         my $off = 0;
1133
1134                         my $blank = copy_spacing($opline);
1135
1136                         for (my $n = 0; $n < $#elements; $n += 2) {
1137                                 $off += length($elements[$n]);
1138
1139                                 my $a = '';
1140                                 $a = 'V' if ($elements[$n] ne '');
1141                                 $a = 'W' if ($elements[$n] =~ /\s$/);
1142                                 $a = 'B' if ($elements[$n] =~ /(\[|\()$/);
1143                                 $a = 'O' if ($elements[$n] eq '');
1144                                 $a = 'E' if ($elements[$n] eq '' && $n == 0);
1145
1146                                 my $op = $elements[$n + 1];
1147
1148                                 my $c = '';
1149                                 if (defined $elements[$n + 2]) {
1150                                         $c = 'V' if ($elements[$n + 2] ne '');
1151                                         $c = 'W' if ($elements[$n + 2] =~ /^\s/);
1152                                         $c = 'B' if ($elements[$n + 2] =~ /^(\)|\]|;)/);
1153                                         $c = 'O' if ($elements[$n + 2] eq '');
1154                                         $c = 'E' if ($elements[$n + 2] =~ /\s*\\$/);
1155                                 } else {
1156                                         $c = 'E';
1157                                 }
1158
1159                                 # Pick up the preceeding and succeeding characters.
1160                                 my $ca = substr($opline, 0, $off);
1161                                 my $cc = '';
1162                                 if (length($opline) >= ($off + length($elements[$n + 1]))) {
1163                                         $cc = substr($opline, $off + length($elements[$n + 1]));
1164                                 }
1165                                 my $cb = "$ca$;$cc";
1166
1167                                 my $ctx = "${a}x${c}";
1168
1169                                 my $at = "(ctx:$ctx)";
1170
1171                                 my $ptr = substr($blank, 0, $off) . "^";
1172                                 my $hereptr = "$hereline$ptr\n";
1173
1174                                 # Classify operators into binary, unary, or
1175                                 # definitions (* only) where they have more
1176                                 # than one mode.
1177                                 my $op_type = substr($curr_values, $off + 1, 1);
1178                                 my $op_left = substr($curr_values, $off, 1);
1179                                 my $is_unary;
1180                                 if ($op_type eq 'T') {
1181                                         $is_unary = 2;
1182                                 } elsif ($op_left eq 'V') {
1183                                         $is_unary = 0;
1184                                 } else {
1185                                         $is_unary = 1;
1186                                 }
1187                                 #if ($op eq '-' || $op eq '&' || $op eq '*') {
1188                                 #       print "UNARY: <$op_left$op_type $is_unary $a:$op:$c> <$ca:$op:$cc> <$unary_ctx>\n";
1189                                 #}
1190
1191                                 # ; should have either the end of line or a space or \ after it
1192                                 if ($op eq ';') {
1193                                         if ($ctx !~ /.x[WEB]/ && $cc !~ /^\\/ &&
1194                                             $cc !~ /^;/) {
1195                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
1196                                         }
1197
1198                                 # // is a comment
1199                                 } elsif ($op eq '//') {
1200
1201                                 # -> should have no spaces
1202                                 } elsif ($op eq '->') {
1203                                         if ($ctx =~ /Wx.|.xW/) {
1204                                                 ERROR("no spaces around that '$op' $at\n" . $hereptr);
1205                                         }
1206
1207                                 # , must have a space on the right.
1208                                 } elsif ($op eq ',') {
1209                                         if ($ctx !~ /.xW|.xE/ && $cc !~ /^}/) {
1210                                                 ERROR("need space after that '$op' $at\n" . $hereptr);
1211                                         }
1212
1213                                 # '*' as part of a type definition -- reported already.
1214                                 } elsif ($op eq '*' && $is_unary == 2) {
1215                                         #warn "'*' is part of type\n";
1216
1217                                 # unary operators should have a space before and
1218                                 # none after.  May be left adjacent to another
1219                                 # unary operator, or a cast
1220                                 } elsif ($op eq '!' || $op eq '~' ||
1221                                          ($is_unary && ($op eq '*' || $op eq '-' || $op eq '&'))) {
1222                                         if ($ctx !~ /[WEB]x./ && $ca !~ /(?:\)|!|~|\*|-|\&|\||\+\+|\-\-|\{)$/) {
1223                                                 ERROR("need space before that '$op' $at\n" . $hereptr);
1224                                         }
1225                                         if ($ctx =~ /.xW/) {
1226                                                 ERROR("no space after that '$op' $at\n" . $hereptr);
1227                                         }
1228
1229                                 # unary ++ and unary -- are allowed no space on one side.
1230                                 } elsif ($op eq '++' or $op eq '--') {
1231                                         if ($ctx !~ /[WOB]x[^W]/ && $ctx !~ /[^W]x[WOBE]/) {
1232                                                 ERROR("need space one side of that '$op' $at\n" . $hereptr);
1233                                         }
1234                                         if ($ctx =~ /Wx./ && $cc =~ /^;/) {
1235                                                 ERROR("no space before that '$op' $at\n" . $hereptr);
1236                                         }
1237
1238                                 # << and >> may either have or not have spaces both sides
1239                                 } elsif ($op eq '<<' or $op eq '>>' or
1240                                          $op eq '&' or $op eq '^' or $op eq '|' or
1241                                          $op eq '+' or $op eq '-' or
1242                                          $op eq '*' or $op eq '/')
1243                                 {
1244                                         if ($ctx !~ /VxV|WxW|VxE|WxE|VxO/) {
1245                                                 ERROR("need consistent spacing around '$op' $at\n" .
1246                                                         $hereptr);
1247                                         }
1248
1249                                 # All the others need spaces both sides.
1250                                 } elsif ($ctx !~ /[EW]x[WE]/) {
1251                                         # Ignore email addresses <foo@bar>
1252                                         if (!($op eq '<' && $cb =~ /$;\S+\@\S+>/) &&
1253                                             !($op eq '>' && $cb =~ /<\S+\@\S+$;/)) {
1254                                                 ERROR("need spaces around that '$op' $at\n" . $hereptr);
1255                                         }
1256                                 }
1257                                 $off += length($elements[$n + 1]);
1258                         }
1259                 }
1260
1261 # check for multiple assignments
1262                 if ($line =~ /^.\s*$Lval\s*=\s*$Lval\s*=(?!=)/) {
1263                         CHK("multiple assignments should be avoided\n" . $herecurr);
1264                 }
1265
1266 ## # check for multiple declarations, allowing for a function declaration
1267 ## # continuation.
1268 ##              if ($line =~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Ident.*/ &&
1269 ##                  $line !~ /^.\s*$Type\s+$Ident(?:\s*=[^,{]*)?\s*,\s*$Type\s*$Ident.*/) {
1270 ##
1271 ##                      # Remove any bracketed sections to ensure we do not
1272 ##                      # falsly report the parameters of functions.
1273 ##                      my $ln = $line;
1274 ##                      while ($ln =~ s/\([^\(\)]*\)//g) {
1275 ##                      }
1276 ##                      if ($ln =~ /,/) {
1277 ##                              WARN("declaring multiple variables together should be avoided\n" . $herecurr);
1278 ##                      }
1279 ##              }
1280
1281 #need space before brace following if, while, etc
1282                 if (($line =~ /\(.*\){/ && $line !~ /\($Type\){/) ||
1283                     $line =~ /do{/) {
1284                         ERROR("need a space before the open brace '{'\n" . $herecurr);
1285                 }
1286
1287 # closing brace should have a space following it when it has anything
1288 # on the line
1289                 if ($line =~ /}(?!(?:,|;|\)))\S/) {
1290                         ERROR("need a space after that close brace '}'\n" . $herecurr);
1291                 }
1292
1293 # check spacing on square brackets
1294                 if ($line =~ /\[\s/ && $line !~ /\[\s*$/) {
1295                         ERROR("no space after that open square bracket '['\n" . $herecurr);
1296                 }
1297                 if ($line =~ /\s\]/) {
1298                         ERROR("no space before that close square bracket ']'\n" . $herecurr);
1299                 }
1300
1301 # check spacing on paretheses
1302                 if ($line =~ /\(\s/ && $line !~ /\(\s*(?:\\)?$/ &&
1303                     $line !~ /for\s*\(\s+;/) {
1304                         ERROR("no space after that open parenthesis '('\n" . $herecurr);
1305                 }
1306                 if ($line =~ /\s\)/ && $line !~ /^.\s*\)/ &&
1307                     $line !~ /for\s*\(.*;\s+\)/) {
1308                         ERROR("no space before that close parenthesis ')'\n" . $herecurr);
1309                 }
1310
1311 #goto labels aren't indented, allow a single space however
1312                 if ($line=~/^.\s+[A-Za-z\d_]+:(?![0-9]+)/ and
1313                    !($line=~/^. [A-Za-z\d_]+:/) and !($line=~/^.\s+default:/)) {
1314                         WARN("labels should not be indented\n" . $herecurr);
1315                 }
1316
1317 # Need a space before open parenthesis after if, while etc
1318                 if ($line=~/\b(if|while|for|switch)\(/) {
1319                         ERROR("need a space before the open parenthesis '('\n" . $herecurr);
1320                 }
1321
1322 # Check for illegal assignment in if conditional.
1323                 if ($line =~ /\bif\s*\(/) {
1324                         my ($s, $c) = ctx_statement_block($linenr, $realcnt, 0);
1325
1326                         if ($c =~ /\bif\s*\(.*[^<>!=]=[^=].*/) {
1327                                 ERROR("do not use assignment in if condition ($c)\n" . $herecurr);
1328                         }
1329
1330                         # Find out what is on the end of the line after the
1331                         # conditional.
1332                         substr($s, 0, length($c)) = '';
1333                         $s =~ s/\n.*//g;
1334
1335                         if (length($c) && $s !~ /^\s*({|;|\/\*.*\*\/)?\s*\\*\s*$/) {
1336                                 ERROR("trailing statements should be on next line\n" . $herecurr);
1337                         }
1338                 }
1339
1340 # if and else should not have general statements after it
1341                 if ($line =~ /^.\s*(?:}\s*)?else\b(.*)/ &&
1342                     $1 !~ /^\s*(?:\sif|{|\\|$)/) {
1343                         ERROR("trailing statements should be on next line\n" . $herecurr);
1344                 }
1345
1346                 # Check for }<nl>else {, these must be at the same
1347                 # indent level to be relevant to each other.
1348                 if ($prevline=~/}\s*$/ and $line=~/^.\s*else\s*/ and
1349                                                 $previndent == $indent) {
1350                         ERROR("else should follow close brace '}'\n" . $hereprev);
1351                 }
1352
1353 #studly caps, commented out until figure out how to distinguish between use of existing and adding new
1354 #               if (($line=~/[\w_][a-z\d]+[A-Z]/) and !($line=~/print/)) {
1355 #                   print "No studly caps, use _\n";
1356 #                   print "$herecurr";
1357 #                   $clean = 0;
1358 #               }
1359
1360 #no spaces allowed after \ in define
1361                 if ($line=~/\#define.*\\\s$/) {
1362                         WARN("Whitepspace after \\ makes next lines useless\n" . $herecurr);
1363                 }
1364
1365 #warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
1366                 if ($tree && $rawline =~ m{^.\#\s*include\s*\<asm\/(.*)\.h\>}) {
1367                         my $checkfile = "$root/include/linux/$1.h";
1368                         if (-f $checkfile && $1 ne 'irq.h') {
1369                                 CHK("Use #include <linux/$1.h> instead of <asm/$1.h>\n" .
1370                                         $herecurr);
1371                         }
1372                 }
1373
1374 # multi-statement macros should be enclosed in a do while loop, grab the
1375 # first statement and ensure its the whole macro if its not enclosed
1376 # in a known goot container
1377                 if ($prevline =~ /\#define.*\\/ &&
1378                    $prevline !~/(?:do\s+{|\(\{|\{)/ &&
1379                    $line !~ /(?:do\s+{|\(\{|\{)/ &&
1380                    $line !~ /^.\s*$Declare\s/) {
1381                         # Grab the first statement, if that is the entire macro
1382                         # its ok.  This may start either on the #define line
1383                         # or the one below.
1384                         my $ln = $linenr;
1385                         my $cnt = $realcnt;
1386                         my $off = 0;
1387
1388                         # If the macro starts on the define line start
1389                         # grabbing the statement after the identifier
1390                         $prevline =~ m{^(.#\s*define\s*$Ident(?:\([^\)]*\))?\s*)(.*)\\\s*$};
1391                         ##print "1<$1> 2<$2>\n";
1392                         if (defined $2 && $2 ne '') {
1393                                 $off = length($1);
1394                                 $ln--;
1395                                 $cnt++;
1396                                 while ($lines[$ln - 1] =~ /^-/) {
1397                                         $ln--;
1398                                         $cnt++;
1399                                 }
1400                         }
1401                         my @ctx = ctx_statement($ln, $cnt, $off);
1402                         my $ctx_ln = $ln + $#ctx + 1;
1403                         my $ctx = join("\n", @ctx);
1404
1405                         # Pull in any empty extension lines.
1406                         while ($ctx =~ /\\$/ &&
1407                                $lines[$ctx_ln - 1] =~ /^.\s*(?:\\)?$/) {
1408                                 $ctx .= $lines[$ctx_ln - 1];
1409                                 $ctx_ln++;
1410                         }
1411
1412                         if ($ctx =~ /\\$/) {
1413                                 if ($ctx =~ /;/) {
1414                                         ERROR("Macros with multiple statements should be enclosed in a do - while loop\n" . "$here\n$ctx\n");
1415                                 } else {
1416                                         ERROR("Macros with complex values should be enclosed in parenthesis\n" . "$here\n$ctx\n");
1417                                 }
1418                         }
1419                 }
1420
1421 # check for redundant bracing round if etc
1422                 if ($line =~ /\b(if|while|for|else)\b/) {
1423                         # Locate the end of the opening statement.
1424                         my @control = ctx_statement($linenr, $realcnt, 0);
1425                         my $nr = $linenr + (scalar(@control) - 1);
1426                         my $cnt = $realcnt - (scalar(@control) - 1);
1427
1428                         my $off = $realcnt - $cnt;
1429                         #print "$off: line<$line>end<" . $lines[$nr - 1] . ">\n";
1430
1431                         # If this is is a braced statement group check it
1432                         if ($lines[$nr - 1] =~ /{\s*$/) {
1433                                 my ($lvl, @block) = ctx_block_level($nr, $cnt);
1434
1435                                 my $stmt = join("\n", @block);
1436                                 # Drop the diff line leader.
1437                                 $stmt =~ s/\n./\n/g;
1438                                 # Drop the code outside the block.
1439                                 $stmt =~ s/(^[^{]*){\s*//;
1440                                 my $before = $1;
1441                                 $stmt =~ s/\s*}([^}]*$)//;
1442                                 my $after = $1;
1443
1444                                 #print "block<" . join(' ', @block) . "><" . scalar(@block) . ">\n";
1445                                 #print "stmt<$stmt>\n\n";
1446
1447                                 # Count the newlines, if there is only one
1448                                 # then the block should not have {}'s.
1449                                 my @lines = ($stmt =~ /\n/g);
1450                                 #print "lines<" . scalar(@lines) . ">\n";
1451                                 if ($lvl == 0 && scalar(@lines) == 0 &&
1452                                     $stmt !~ /{/ && $stmt !~ /\bif\b/ &&
1453                                     $before !~ /}/ && $after !~ /{/) {
1454                                         my $herectx = "$here\n" . join("\n", @control, @block[1 .. $#block]) . "\n";
1455                                         shift(@block);
1456                                         WARN("braces {} are not necessary for single statement blocks\n" . $herectx);
1457                                 }
1458                         }
1459                 }
1460
1461 # don't include deprecated include files (uses RAW line)
1462                 for my $inc (@dep_includes) {
1463                         if ($rawline =~ m@\#\s*include\s*\<$inc>@) {
1464                                 ERROR("Don't use <$inc>: see Documentation/feature-removal-schedule.txt\n" . $herecurr);
1465                         }
1466                 }
1467
1468 # don't use deprecated functions
1469                 for my $func (@dep_functions) {
1470                         if ($line =~ /\b$func\b/) {
1471                                 ERROR("Don't use $func(): see Documentation/feature-removal-schedule.txt\n" . $herecurr);
1472                         }
1473                 }
1474
1475 # no volatiles please
1476                 my $asm_volatile = qr{\b(__asm__|asm)\s+(__volatile__|volatile)\b};
1477                 if ($line =~ /\bvolatile\b/ && $line !~ /$asm_volatile/) {
1478                         WARN("Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt\n" . $herecurr);
1479                 }
1480
1481 # SPIN_LOCK_UNLOCKED & RW_LOCK_UNLOCKED are deprecated
1482                 if ($line =~ /\b(SPIN_LOCK_UNLOCKED|RW_LOCK_UNLOCKED)/) {
1483                         ERROR("Use of $1 is deprecated: see Documentation/spinlocks.txt\n" . $herecurr);
1484                 }
1485
1486 # warn about #if 0
1487                 if ($line =~ /^.#\s*if\s+0\b/) {
1488                         CHK("if this code is redundant consider removing it\n" .
1489                                 $herecurr);
1490                 }
1491
1492 # check for needless kfree() checks
1493                 if ($prevline =~ /\bif\s*\(([^\)]*)\)/) {
1494                         my $expr = $1;
1495                         if ($line =~ /\bkfree\(\Q$expr\E\);/) {
1496                                 WARN("kfree(NULL) is safe this check is probabally not required\n" . $hereprev);
1497                         }
1498                 }
1499
1500 # warn about #ifdefs in C files
1501 #               if ($line =~ /^.#\s*if(|n)def/ && ($realfile =~ /\.c$/)) {
1502 #                       print "#ifdef in C files should be avoided\n";
1503 #                       print "$herecurr";
1504 #                       $clean = 0;
1505 #               }
1506
1507 # warn about spacing in #ifdefs
1508                 if ($line =~ /^.#\s*(ifdef|ifndef|elif)\s\s+/) {
1509                         ERROR("exactly one space required after that #$1\n" . $herecurr);
1510                 }
1511
1512 # check for spinlock_t definitions without a comment.
1513                 if ($line =~ /^.\s*(struct\s+mutex|spinlock_t)\s+\S+;/) {
1514                         my $which = $1;
1515                         if (!ctx_has_comment($first_line, $linenr)) {
1516                                 CHK("$1 definition without comment\n" . $herecurr);
1517                         }
1518                 }
1519 # check for memory barriers without a comment.
1520                 if ($line =~ /\b(mb|rmb|wmb|read_barrier_depends|smp_mb|smp_rmb|smp_wmb|smp_read_barrier_depends)\(/) {
1521                         if (!ctx_has_comment($first_line, $linenr)) {
1522                                 CHK("memory barrier without comment\n" . $herecurr);
1523                         }
1524                 }
1525 # check of hardware specific defines
1526                 if ($line =~ m@^.#\s*if.*\b(__i386__|__powerpc64__|__sun__|__s390x__)\b@ && $realfile !~ m@include/asm-@) {
1527                         CHK("architecture specific defines should be avoided\n" .  $herecurr);
1528                 }
1529
1530 # check the location of the inline attribute, that it is between
1531 # storage class and type.
1532                 if ($line =~ /\b$Type\s+$Inline\b/ ||
1533                     $line =~ /\b$Inline\s+$Storage\b/) {
1534                         ERROR("inline keyword should sit between storage class and type\n" . $herecurr);
1535                 }
1536
1537 # Check for __inline__ and __inline, prefer inline
1538                 if ($line =~ /\b(__inline__|__inline)\b/) {
1539                         WARN("plain inline is preferred over $1\n" . $herecurr);
1540                 }
1541
1542 # check for new externs in .c files.
1543                 if ($line =~ /^.\s*extern\s/ && ($realfile =~ /\.c$/)) {
1544                         WARN("externs should be avoided in .c files\n" .  $herecurr);
1545                 }
1546
1547 # checks for new __setup's
1548                 if ($rawline =~ /\b__setup\("([^"]*)"/) {
1549                         my $name = $1;
1550
1551                         if (!grep(/$name/, @setup_docs)) {
1552                                 CHK("__setup appears un-documented -- check Documentation/kernel-parameters.txt\n" . $herecurr);
1553                         }
1554                 }
1555
1556 # check for pointless casting of kmalloc return
1557                 if ($line =~ /\*\s*\)\s*k[czm]alloc\b/) {
1558                         WARN("unnecessary cast may hide bugs, see http://c-faq.com/malloc/mallocnocast.html\n" . $herecurr);
1559                 }
1560         }
1561
1562         # In mailback mode only produce a report in the negative, for
1563         # things that appear to be patches.
1564         if ($mailback && ($clean == 1 || !$is_patch)) {
1565                 exit(0);
1566         }
1567
1568         # This is not a patch, and we are are in 'no-patch' mode so
1569         # just keep quiet.
1570         if (!$chk_patch && !$is_patch) {
1571                 exit(0);
1572         }
1573
1574         if (!$is_patch) {
1575                 ERROR("Does not appear to be a unified-diff format patch\n");
1576         }
1577         if ($is_patch && $chk_signoff && $signoff == 0) {
1578                 ERROR("Missing Signed-off-by: line(s)\n");
1579         }
1580
1581         print report_dump();
1582         if ($summary) {
1583                 print "total: $cnt_error errors, $cnt_warn warnings, " .
1584                         (($check)? "$cnt_chk checks, " : "") .
1585                         "$cnt_lines lines checked\n";
1586                 print "\n" if ($quiet == 0);
1587         }
1588
1589         if ($clean == 1 && $quiet == 0) {
1590                 print "Your patch has no obvious style problems and is ready for submission.\n"
1591         }
1592         if ($clean == 0 && $quiet == 0) {
1593                 print "Your patch has style problems, please review.  If any of these errors\n";
1594                 print "are false positives report them to the maintainer, see\n";
1595                 print "CHECKPATCH in MAINTAINERS.\n";
1596         }
1597         return $clean;
1598 }