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	if ($line =~ m/^(\s*extern|unsigned|char|short|int|long|void)\b/) {
 73		printf STDERR "$filename:$lineno: " .
 74			      "userspace cannot reference function or " .
 75			      "variable defined in the kernel\n";
 76	}
 77}
 78
 79sub check_config
 80{
 81	if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) {
 82		printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n";
 83	}
 84}
 85
 86my $linux_asm_types;
 87sub check_asm_types
 88{
 89	if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
 90		return;
 91	}
 92	if ($lineno == 1) {
 93		$linux_asm_types = 0;
 94	} elsif ($linux_asm_types >= 1) {
 95		return;
 96	}
 97	if ($line =~ m/^\s*#\s*include\s+<asm\/types.h>/) {
 98		$linux_asm_types = 1;
 99		printf STDERR "$filename:$lineno: " .
100		"include of <linux/types.h> is preferred over <asm/types.h>\n"
101		# Warn until headers are all fixed
102		#$ret = 1;
103	}
104}
105
106my $linux_types;
107my %import_stack = ();
108sub check_include_typesh
109{
110	my $path = $_[0];
111	my $import_path;
112
113	my $fh;
114	my @file_paths = ($path, $dir . "/" .  $path, dirname($filename) . "/" . $path);
115	for my $possible ( @file_paths ) {
116	    if (not $import_stack{$possible} and open($fh, '<', $possible)) {
117		$import_path = $possible;
118		$import_stack{$import_path} = 1;
119		last;
120	    }
121	}
122	if (eof $fh) {
123	    return;
124	}
125
126	my $line;
127	while ($line = <$fh>) {
128		if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
129			$linux_types = 1;
130			last;
131		}
132		if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
133			check_include_typesh($included);
134		}
135	}
136	close $fh;
137	delete $import_stack{$import_path};
138}
139
140sub check_sizetypes
141{
142	if ($filename =~ /types.h|int-l64.h|int-ll64.h/o) {
143		return;
144	}
145	if ($lineno == 1) {
146		$linux_types = 0;
147	} elsif ($linux_types >= 1) {
148		return;
149	}
150	if ($line =~ m/^\s*#\s*include\s+<linux\/types.h>/) {
151		$linux_types = 1;
152		return;
153	}
154	if (my $included = ($line =~ /^\s*#\s*include\s+[<"](\S+)[>"]/)[0]) {
155		check_include_typesh($included);
156	}
157	if ($line =~ m/__[us](8|16|32|64)\b/) {
158		printf STDERR "$filename:$lineno: " .
159		              "found __[us]{8,16,32,64} type " .
160		              "without #include <linux/types.h>\n";
161		$linux_types = 2;
162		# Warn until headers are all fixed
163		#$ret = 1;
164	}
165}