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
 21use strict;
 22use File::Basename;
 23
 24my ($dir, $arch, @files) = @ARGV;
 25
 26my $ret = 0;
 27my $line;
 28my $lineno = 0;
 29my $filename;
 30
 31foreach 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}
 47exit $ret;
 48
 49sub check_include
 50{
 51	if ($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			$ret = 1;
 62		}
 63	}
 64}
 65
 66sub check_declarations
 67{
 68	if ($line =~m/^(\s*extern|unsigned|char|short|int|long|void)\b/) {
 69		printf STDERR "$filename:$lineno: " .
 70			      "userspace cannot reference function or " .
 71			      "variable defined in the kernel\n";
 72	}
 73}
 74
 75sub check_config
 76{
 77	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 78		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 79	}
 80}
 81
 82my $linux_asm_types;
 83sub check_asm_types
 84{
 85	if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
 86		return;
 87	}
 88	if ($lineno == 1) {
 89		$linux_asm_types = 0;
 90	} elsif ($linux_asm_types >= 1) {
 91		return;
 92	}
 93	if ($line =~ m/^\s*#\s*include\s+<asm\/types.h>/) {
 94		$linux_asm_types = 1;
 95		printf STDERR "$filename:$lineno: " .
 96		"include of <linux/types.h> is preferred over <asm/types.h>\n"
 97		# Warn until headers are all fixed
 98		#$ret = 1;
 99	}
100}
101
102my $linux_types;
103my %import_stack = ();
104sub check_include_typesh
105{
106	my $path = $_[0];
107	my $import_path;
108
109	my $fh;
110	my @file_paths = ($path, $dir . "/" .  $path, dirname($filename) . "/" . $path);
111	for my $possible ( @file_paths ) {
112	    if (not $import_stack{$possible} and open($fh, '<', $possible)) {
113		$import_path = $possible;
114		$import_stack{$import_path} = 1;
115		last;
116	    }
117	}
118	if (eof $fh) {
119	    return;
120	}
121
122	my $line;
123	while ($line = <$fh>) {
124		if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
125			$linux_types = 1;
126			last;
127		}
128		if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
129			check_include_typesh($included);
130		}
131	}
132	close $fh;
133	delete $import_stack{$import_path};
134}
135
136sub check_sizetypes
137{
138	if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
139		return;
140	}
141	if ($lineno == 1) {
142		$linux_types = 0;
143	} elsif ($linux_types >= 1) {
144		return;
145	}
146	if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
147		$linux_types = 1;
148		return;
149	}
150	if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
151		check_include_typesh($included);
152	}
153	if ($line =~ m/__[us](8|16|32|64)\b/) {
154		printf STDERR "$filename:$lineno: " .
155		              "found __[us]{8,16,32,64} type " .
156		              "without #include <linux/types.h>\n";
157		$linux_types = 2;
158		# Warn until headers are all fixed
159		#$ret = 1;
160	}
161}