hw/arm/virt: parameter passing cleanups
[qemu.git] / scripts / clean-header-guards.pl
1 #!/usr/bin/perl -w
2 #
3 # Clean up include guards in headers
4 #
5 # Copyright (C) 2016 Red Hat, Inc.
6 #
7 # Authors:
8 # Markus Armbruster <armbru@redhat.com>
9 #
10 # This work is licensed under the terms of the GNU GPL, version 2 or
11 # (at your option) any later version. See the COPYING file in the
12 # top-level directory.
13 #
14 # Usage: scripts/clean-header-guards.pl [OPTION]... [FILE]...
15 # -c CC Use a compiler other than cc
16 # -n Suppress actual cleanup
17 # -v Show which files are cleaned up, and which are skipped
18 #
19 # Does the following:
20 # - Header files without a recognizable header guard are skipped.
21 # - Clean up any untidy header guards in-place. Warn if the cleanup
22 # renames guard symbols, and explain how to find occurences of these
23 # symbols that may have to be updated manually.
24 # - Warn about duplicate header guard symbols. To make full use of
25 # this warning, you should clean up *all* headers in one run.
26 # - Warn when preprocessing a header with its guard symbol defined
27 # produces anything but whitespace. The preprocessor is run like
28 # "cc -E -DGUARD_H -c -P -", and fed the test program on stdin.
29
30 use strict;
31 use Getopt::Std;
32
33 # Stuff we don't want to clean because we import it into our tree:
34 my $exclude = qr,^(disas/libvixl/|include/standard-headers/
35 |linux-headers/|pc-bios/|tests/tcg/|tests/multiboot/),x;
36 # Stuff that is expected to fail the preprocessing test:
37 my $exclude_cpp = qr,^include/libdecnumber/decNumberLocal.h,;
38
39 my %guarded = ();
40 my %old_guard = ();
41
42 our $opt_c = "cc";
43 our $opt_n = 0;
44 our $opt_v = 0;
45 getopts("c:nv");
46
47 sub skipping {
48 my ($fname, $msg, $line1, $line2) = @_;
49
50 return if !$opt_v or $fname =~ $exclude;
51 print "$fname skipped: $msg\n";
52 print " $line1" if defined $line1;
53 print " $line2" if defined $line2;
54 }
55
56 sub gripe {
57 my ($fname, $msg) = @_;
58 return if $fname =~ $exclude;
59 print STDERR "$fname: warning: $msg\n";
60 }
61
62 sub slurp {
63 my ($fname) = @_;
64 local $/; # slurp
65 open(my $in, "<", $fname)
66 or die "can't open $fname for reading: $!";
67 return <$in>;
68 }
69
70 sub unslurp {
71 my ($fname, $contents) = @_;
72 open (my $out, ">", $fname)
73 or die "can't open $fname for writing: $!";
74 print $out $contents
75 or die "error writing $fname: $!";
76 close $out
77 or die "error writing $fname: $!";
78 }
79
80 sub fname2guard {
81 my ($fname) = @_;
82 $fname =~ tr/a-z/A-Z/;
83 $fname =~ tr/A-Z0-9/_/cs;
84 return $fname;
85 }
86
87 sub preprocess {
88 my ($fname, $guard) = @_;
89
90 open(my $pipe, "-|", "$opt_c -E -D$guard -c -P - <$fname")
91 or die "can't run $opt_c: $!";
92 while (<$pipe>) {
93 if ($_ =~ /\S/) {
94 gripe($fname, "not blank after preprocessing");
95 last;
96 }
97 }
98 close $pipe
99 or gripe($fname, "preprocessing failed ($opt_c exit status $?)");
100 }
101
102 for my $fname (@ARGV) {
103 my $text = slurp($fname);
104
105 $text =~ m,\A(\s*\n|\s*//\N*\n|\s*/\*.*?\*/\s*\n)*|,msg;
106 my $pre = $&;
107 unless ($text =~ /\G(.*\n)/g) {
108 $text =~ /\G.*/;
109 skipping($fname, "no recognizable header guard", "$&\n");
110 next;
111 }
112 my $line1 = $1;
113 unless ($text =~ /\G(.*\n)/g) {
114 $text =~ /\G.*/;
115 skipping($fname, "no recognizable header guard", "$&\n");
116 next;
117 }
118 my $line2 = $1;
119 my $body = substr($text, pos($text));
120
121 unless ($line1 =~ /^\s*\#\s*(if\s*\!\s*defined(\s*\()?|ifndef)\s*
122 ([A-Za-z0-9_]+)/x) {
123 skipping($fname, "no recognizable header guard", $line1, $line2);
124 next;
125 }
126 my $guard = $3;
127 unless ($line2 =~ /^\s*\#\s*define\s+([A-Za-z0-9_]+)/) {
128 skipping($fname, "no recognizable header guard", $line1, $line2);
129 next;
130 }
131 my $guard2 = $1;
132 unless ($guard2 eq $guard) {
133 skipping($fname, "mismatched header guard ($guard vs. $guard2) ",
134 $line1, $line2);
135 next;
136 }
137
138 unless ($body =~ m,\A((.*\n)*)
139 (\s*\#\s*endif\s*(/\*\s*.*\s*\*/\s*)?\n?)
140 (\n|\s)*\Z,x) {
141 skipping($fname, "can't find end of header guard");
142 next;
143 }
144 $body = $1;
145 my $line3 = $3;
146 my $endif_comment = $4;
147
148 my $oldg = $guard;
149
150 unless ($fname =~ $exclude) {
151 my @issues = ();
152 $guard =~ tr/a-z/A-Z/
153 and push @issues, "contains lowercase letters";
154 $guard =~ s/^_+//
155 and push @issues, "is a reserved identifier";
156 $guard =~ s/(_H)?_*$/_H/
157 and $& ne "_H" and push @issues, "doesn't end with _H";
158 unless ($guard =~ /^[A-Z][A-Z0-9_]*_H/) {
159 skipping($fname, "can't clean up odd guard symbol $oldg\n",
160 $line1, $line2);
161 next;
162 }
163
164 my $exp = fname2guard($fname =~ s,.*/,,r);
165 unless ($guard =~ /\Q$exp\E\Z/) {
166 $guard = fname2guard($fname =~ s,^include/,,r);
167 push @issues, "doesn't match the file name";
168 }
169 if (@issues and $opt_v) {
170 print "$fname guard $oldg needs cleanup:\n ",
171 join(", ", @issues), "\n";
172 }
173 }
174
175 $old_guard{$guard} = $oldg
176 if $guard ne $oldg;
177
178 if (exists $guarded{$guard}) {
179 gripe($fname, "guard $guard also used by $guarded{$guard}");
180 } else {
181 $guarded{$guard} = $fname;
182 }
183
184 unless ($fname =~ $exclude) {
185 my $newl1 = "#ifndef $guard\n";
186 my $newl2 = "#define $guard\n";
187 my $newl3 = "#endif\n";
188 $newl3 =~ s,\Z, /* $guard */, if defined $endif_comment;
189 if ($line1 ne $newl1 or $line2 ne $newl2 or $line3 ne $newl3) {
190 $pre =~ s/\n*\Z/\n\n/ if $pre =~ /\N/;
191 $body =~ s/\A\n*/\n/;
192 if ($opt_n) {
193 print "$fname would be cleaned up\n" if $opt_v;
194 } else {
195 unslurp($fname, "$pre$newl1$newl2$body$newl3");
196 print "$fname cleaned up\n" if $opt_v;
197 }
198 }
199 }
200
201 preprocess($fname, $opt_n ? $oldg : $guard)
202 unless $fname =~ $exclude or $fname =~ $exclude_cpp;
203 }
204
205 if (%old_guard) {
206 print STDERR "warning: guard symbol renaming may break things\n";
207 for my $guard (sort keys %old_guard) {
208 print STDERR " $old_guard{$guard} -> $guard\n";
209 }
210 print STDERR "To find uses that may have to be updated try:\n";
211 print STDERR " git grep -Ew '", join("|", sort values %old_guard),
212 "'\n";
213 }