scripts/headers_check.pl

   1 #!/usr/bin/env perl
   2 #
   3 # headers_check.pl execute a number of trivial consistency checks
   4 #
   5 # Usage: headers_check.pl dir arch [files...]
   6 # dir:   dir to look for included files
   7 # arch:  architecture
   8 # files: list of files to check
   9 #
  10 # The script reads the supplied files line by line and:
  11 #
  12 # 1) for each include statement it checks if the
  13 #    included file actually exists.
  14 #    Only include files located in asm* and linux* are checked.
  15 #    The rest are assumed to be system include files.
  16 #
  17 # 2) It is checked that prototypes does not use "extern"
  18 #
  19 # 3) Check for leaked CONFIG_ symbols
  20
  21 use warnings;
  22 use strict;
  23 use File::Basename;
  24
  25 my ($dir, $arch, @files) = @ARGV;
  26
  27 my $ret = 0;
  28 my $line;
  29 my $lineno = 0;
  30 my $filename;
  31
  32 foreach my $file (@files) {
  33         $filename = $file;
  34
  35         open(my $fh, '<', $filename)
  36                 or die "$filename: $!\n";
  37         $lineno = 0;
  38         while ($line = <$fh>) {
  39                 $lineno++;
  40                 &check_include();
  41                 &check_asm_types();
  42                 &check_sizetypes();
  43                 &check_declarations();
  44                 # Dropped for now. Too much noise &check_config();
  45         }
  46         close $fh;
  47 }
  48 exit $ret;
  49
  50 sub check_include
  51 {
  52         if ($line =~ m/^\s*#\s*include\s+<((asm|linux).*)>/) {
  53                 my $inc = $1;
  54                 my $found;
  55                 $found = stat($dir . "/" . $inc);
  56                 if (!$found) {
  57                         $inc =~ s#asm/#asm-$arch/#;
  58                         $found = stat($dir . "/" . $inc);
  59                 }
  60                 if (!$found) {
  61                         printf STDERR "$filename:$lineno: included file '$inc' is not exported\n";
  62                         $ret = 1;
  63                 }
  64         }
  65 }
  66
  67 sub check_declarations
  68 {
  69         # soundcard.h is what it is
  70         if ($line =~ m/^void seqbuf_dump\(void\);/) {
  71                 return;
  72         }
  73         # drm headers are being C++ friendly
  74         if ($line =~ m/^extern "C"/) {
  75                 return;
  76         }
  77         if ($line =~ m/^(\s*extern|unsigned|char|short|int|long|void)\b/) {
  78                 printf STDERR "$filename:$lineno: " .
  79                               "userspace cannot reference function or " .
  80                               "variable defined in the kernel\n";
  81         }
  82 }
  83
  84 sub check_config
  85 {
  86         if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
  87                 printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
  88         }
  89 }
  90
  91 my $linux_asm_types;
  92 sub check_asm_types
  93 {
  94         if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
  95                 return;
  96         }
  97         if ($lineno == 1) {
  98                 $linux_asm_types = 0;
  99         } elsif ($linux_asm_types >= 1) {
 100                 return;
 101         }
 102         if ($line =~ m/^\s*#\s*include\s+<asm\/types.h>/) {
 103                 $linux_asm_types = 1;
 104                 printf STDERR "$filename:$lineno: " .
 105                 "include of <linux/types.h> is preferred over <asm/types.h>\n"
 106                 # Warn until headers are all fixed
 107                 #$ret = 1;
 108         }
 109 }
 110
 111 my $linux_types;
 112 my %import_stack = ();
 113 sub check_include_typesh
 114 {
 115         my $path = $_[0];
 116         my $import_path;
 117
 118         my $fh;
 119         my @file_paths = ($path, $dir . "/" .  $path, dirname($filename) . "/" . $path);
 120         for my $possible ( @file_paths ) {
 121             if (not $import_stack{$possible} and open($fh, '<', $possible)) {
 122                 $import_path = $possible;
 123                 $import_stack{$import_path} = 1;
 124                 last;
 125             }
 126         }
 127         if (eof $fh) {
 128             return;
 129         }
 130
 131         my $line;
 132         while ($line = <$fh>) {
 133                 if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
 134                         $linux_types = 1;
 135                         last;
 136                 }
 137                 if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
 138                         check_include_typesh($included);
 139                 }
 140         }
 141         close $fh;
 142         delete $import_stack{$import_path};
 143 }
 144
 145 sub check_sizetypes
 146 {
 147         if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
 148                 return;
 149         }
 150         if ($lineno == 1) {
 151                 $linux_types = 0;
 152         } elsif ($linux_types >= 1) {
 153                 return;
 154         }
 155         if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
 156                 $linux_types = 1;
 157                 return;
 158         }
 159         if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
 160                 check_include_typesh($included);
 161         }
 162         if ($line =~ m/__[us](8|16|32|64)\b/) {
 163                 printf STDERR "$filename:$lineno: " .
 164                               "found __[us]{8,16,32,64} type " .
 165                               "without #include <linux/types.h>\n";
 166                 $linux_types = 2;
 167                 # Warn until headers are all fixed
 168                 #$ret = 1;
 169         }
 170 }