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			$ret = 1;
 62		}
 63	}
 64}
 65
 66sub check_declarations
 67{
 68	# soundcard.h is what it is
 69	if ($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
 83sub 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
 90my $linux_asm_types;
 91sub check_asm_types
 92{
 93	if ($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
110my $linux_types;
111my %import_stack = ();
112sub 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
144sub 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}