scripts/headers_check.pl

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