xref: /linux/scripts/documentation-file-ref-check (revision d25c0634441ca59325f1119cbd203ecda65521b2)
1#!/usr/bin/env perl
2# SPDX-License-Identifier: GPL-2.0
3#
4# Treewide grep for references to files under Documentation, and report
5# non-existing files in stderr.
6
7use warnings;
8use strict;
9use Getopt::Long qw(:config no_auto_abbrev);
10
11my $scriptname = $0;
12$scriptname =~ s,.*/([^/]+/),$1,;
13
14# Parse arguments
15my $help = 0;
16my $fix = 0;
17
18GetOptions(
19	'fix' => \$fix,
20	'h|help|usage' => \$help,
21);
22
23if ($help != 0) {
24    print "$scriptname [--help] [--fix]\n";
25    exit -1;
26}
27
28# Step 1: find broken references
29print "Finding broken references. This may take a while...  " if ($fix);
30
31my %broken_ref;
32
33open IN, "git grep 'Documentation/'|"
34     or die "Failed to run git grep";
35while (<IN>) {
36	next if (!m/^([^:]+):(.*)/);
37
38	my $f = $1;
39	my $ln = $2;
40
41	# Makefiles and scripts contain nasty expressions to parse docs
42	next if ($f =~ m/Makefile/ || $f =~ m/\.sh$/);
43
44	# Skip this script
45	next if ($f eq $scriptname);
46
47	if ($ln =~ m,\b(\S*)(Documentation/[A-Za-z0-9\_\.\,\~/\*\[\]\?+-]*)(.*),) {
48		my $prefix = $1;
49		my $ref = $2;
50		my $base = $2;
51		my $extra = $3;
52
53		# some file references are like:
54		# /usr/src/linux/Documentation/DMA-{API,mapping}.txt
55		# For now, ignore them
56		next if ($extra =~ m/^{/);
57
58		# Remove footnotes at the end like:
59		# Documentation/devicetree/dt-object-internal.txt[1]
60		$ref =~ s/(txt|rst)\[\d+]$/$1/;
61
62		# Remove ending ']' without any '['
63		$ref =~ s/\].*// if (!($ref =~ m/\[/));
64
65		# Remove puntuation marks at the end
66		$ref =~ s/[\,\.]+$//;
67
68		my $fulref = "$prefix$ref";
69
70		$fulref =~ s/^(\<file|ref)://;
71		$fulref =~ s/^[\'\`]+//;
72		$fulref =~ s,^\$\(.*\)/,,;
73		$base =~ s,.*/,,;
74
75		# Remove URL false-positives
76		next if ($fulref =~ m/^http/);
77
78		# Discard some build examples from Documentation/target/tcm_mod_builder.txt
79		next if ($fulref =~ m,mnt/sdb/lio-core-2.6.git/Documentation/target,);
80
81		# Check if exists, evaluating wildcards
82		next if (grep -e, glob("$ref $fulref"));
83
84		# Accept relative Documentation patches for tools/
85		if ($f =~ m/tools/) {
86			my $path = $f;
87			$path =~ s,(.*)/.*,$1,;
88			next if (grep -e, glob("$path/$ref $path/$fulref"));
89		}
90
91		if ($fix) {
92			if (!($ref =~ m/(scripts|Kconfig|Kbuild)/)) {
93				$broken_ref{$ref}++;
94			}
95		} else {
96			print STDERR "$f: $fulref\n";
97		}
98	}
99}
100
101exit 0 if (!$fix);
102
103# Step 2: Seek for file name alternatives
104print "Auto-fixing broken references. Please double-check the results\n";
105
106foreach my $ref (keys %broken_ref) {
107	my $new =$ref;
108
109	# get just the basename
110	$new =~ s,.*/,,;
111
112	my $f="";
113
114	# usual reason for breakage: DT file moved around
115	if ($ref =~ /devicetree/) {
116		my $search = $new;
117		$search =~ s,^.*/,,;
118		$f = qx(find Documentation/devicetree/ -iname "*$search*") if ($search);
119		if (!$f) {
120			# Manufacturer name may have changed
121			$search =~ s/^.*,//;
122			$f = qx(find Documentation/devicetree/ -iname "*$search*") if ($search);
123		}
124	}
125
126	# usual reason for breakage: file renamed to .rst
127	if (!$f) {
128		$new =~ s/\.txt$/.rst/;
129		$f=qx(find . -iname $new) if ($new);
130	}
131
132	# usual reason for breakage: use dash or underline
133	if (!$f) {
134		$new =~ s/[-_]/[-_]/g;
135		$f=qx(find . -iname $new) if ($new);
136	}
137
138	# Wild guess: seek for the same name on another place
139	if (!$f) {
140		$f = qx(find . -iname $new) if ($new);
141	}
142
143	my @find = split /\s+/, $f;
144
145	if (!$f) {
146		print STDERR "ERROR: Didn't find a replacement for $ref\n";
147	} elsif (scalar(@find) > 1) {
148		print STDERR "WARNING: Won't auto-replace, as found multiple files close to $ref:\n";
149		foreach my $j (@find) {
150			$j =~ s,^./,,;
151			print STDERR "    $j\n";
152		}
153	} else {
154		$f = $find[0];
155		$f =~ s,^./,,;
156		print "INFO: Replacing $ref to $f\n";
157		foreach my $j (qx(git grep -l $ref)) {
158			qx(sed "s\@$ref\@$f\@g" -i $j);
159		}
160	}
161}
162