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| -rwxr-xr-x | scripts/clean-header-guards.pl | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/scripts/clean-header-guards.pl b/scripts/clean-header-guards.pl new file mode 100755 index 0000000000..54ab99ae29 --- /dev/null +++ b/scripts/clean-header-guards.pl @@ -0,0 +1,213 @@ +#!/usr/bin/perl -w +# +# Clean up include guards in headers +# +# Copyright (C) 2016 Red Hat, Inc. +# +# Authors: +# Markus Armbruster <armbru@redhat.com> +# +# This work is licensed under the terms of the GNU GPL, version 2 or +# (at your option) any later version. See the COPYING file in the +# top-level directory. +# +# Usage: scripts/clean-header-guards.pl [OPTION]... [FILE]... +# -c CC Use a compiler other than cc +# -n Suppress actual cleanup +# -v Show which files are cleaned up, and which are skipped +# +# Does the following: +# - Header files without a recognizable header guard are skipped. +# - Clean up any untidy header guards in-place. Warn if the cleanup +# renames guard symbols, and explain how to find occurences of these +# symbols that may have to be updated manually. +# - Warn about duplicate header guard symbols. To make full use of +# this warning, you should clean up *all* headers in one run. +# - Warn when preprocessing a header with its guard symbol defined +# produces anything but whitespace. The preprocessor is run like +# "cc -E -DGUARD_H -c -P -", and fed the test program on stdin. + +use strict; +use Getopt::Std; + +# Stuff we don't want to clean because we import it into our tree: +my $exclude = qr,^(disas/libvixl/|include/standard-headers/ + |linux-headers/|pc-bios/|tests/tcg/|tests/multiboot/),x; +# Stuff that is expected to fail the preprocessing test: +my $exclude_cpp = qr,^include/libdecnumber/decNumberLocal.h,; + +my %guarded = (); +my %old_guard = (); + +our $opt_c = "cc"; +our $opt_n = 0; +our $opt_v = 0; +getopts("c:nv"); + +sub skipping { + my ($fname, $msg, $line1, $line2) = @_; + + return if !$opt_v or $fname =~ $exclude; + print "$fname skipped: $msg\n"; + print " $line1" if defined $line1; + print " $line2" if defined $line2; +} + +sub gripe { + my ($fname, $msg) = @_; + return if $fname =~ $exclude; + print STDERR "$fname: warning: $msg\n"; +} + +sub slurp { + my ($fname) = @_; + local $/; # slurp + open(my $in, "<", $fname) + or die "can't open $fname for reading: $!"; + return <$in>; +} + +sub unslurp { + my ($fname, $contents) = @_; + open (my $out, ">", $fname) + or die "can't open $fname for writing: $!"; + print $out $contents + or die "error writing $fname: $!"; + close $out + or die "error writing $fname: $!"; +} + +sub fname2guard { + my ($fname) = @_; + $fname =~ tr/a-z/A-Z/; + $fname =~ tr/A-Z0-9/_/cs; + return $fname; +} + +sub preprocess { + my ($fname, $guard) = @_; + + open(my $pipe, "-|", "$opt_c -E -D$guard -c -P - <$fname") + or die "can't run $opt_c: $!"; + while (<$pipe>) { + if ($_ =~ /\S/) { + gripe($fname, "not blank after preprocessing"); + last; + } + } + close $pipe + or gripe($fname, "preprocessing failed ($opt_c exit status $?)"); +} + +for my $fname (@ARGV) { + my $text = slurp($fname); + + $text =~ m,\A(\s*\n|\s*//\N*\n|\s*/\*.*?\*/\s*\n)*|,msg; + my $pre = $&; + unless ($text =~ /\G(.*\n)/g) { + $text =~ /\G.*/; + skipping($fname, "no recognizable header guard", "$&\n"); + next; + } + my $line1 = $1; + unless ($text =~ /\G(.*\n)/g) { + $text =~ /\G.*/; + skipping($fname, "no recognizable header guard", "$&\n"); + next; + } + my $line2 = $1; + my $body = substr($text, pos($text)); + + unless ($line1 =~ /^\s*\#\s*(if\s*\!\s*defined(\s*\()?|ifndef)\s* + ([A-Za-z0-9_]+)/x) { + skipping($fname, "no recognizable header guard", $line1, $line2); + next; + } + my $guard = $3; + unless ($line2 =~ /^\s*\#\s*define\s+([A-Za-z0-9_]+)/) { + skipping($fname, "no recognizable header guard", $line1, $line2); + next; + } + my $guard2 = $1; + unless ($guard2 eq $guard) { + skipping($fname, "mismatched header guard ($guard vs. $guard2) ", + $line1, $line2); + next; + } + + unless ($body =~ m,\A((.*\n)*) + (\s*\#\s*endif\s*(/\*\s*.*\s*\*/\s*)?\n?) + (\n|\s)*\Z,x) { + skipping($fname, "can't find end of header guard"); + next; + } + $body = $1; + my $line3 = $3; + my $endif_comment = $4; + + my $oldg = $guard; + + unless ($fname =~ $exclude) { + my @issues = (); + $guard =~ tr/a-z/A-Z/ + and push @issues, "contains lowercase letters"; + $guard =~ s/^_+// + and push @issues, "is a reserved identifier"; + $guard =~ s/(_H)?_*$/_H/ + and $& ne "_H" and push @issues, "doesn't end with _H"; + unless ($guard =~ /^[A-Z][A-Z0-9_]*_H/) { + skipping($fname, "can't clean up odd guard symbol $oldg\n", + $line1, $line2); + next; + } + + my $exp = fname2guard($fname =~ s,.*/,,r); + unless ($guard =~ /\Q$exp\E\Z/) { + $guard = fname2guard($fname =~ s,^include/,,r); + push @issues, "doesn't match the file name"; + } + if (@issues and $opt_v) { + print "$fname guard $oldg needs cleanup:\n ", + join(", ", @issues), "\n"; + } + } + + $old_guard{$guard} = $oldg + if $guard ne $oldg; + + if (exists $guarded{$guard}) { + gripe($fname, "guard $guard also used by $guarded{$guard}"); + } else { + $guarded{$guard} = $fname; + } + + unless ($fname =~ $exclude) { + my $newl1 = "#ifndef $guard\n"; + my $newl2 = "#define $guard\n"; + my $newl3 = "#endif\n"; + $newl3 =~ s,\Z, /* $guard */, if defined $endif_comment; + if ($line1 ne $newl1 or $line2 ne $newl2 or $line3 ne $newl3) { + $pre =~ s/\n*\Z/\n\n/ if $pre =~ /\N/; + $body =~ s/\A\n*/\n/; + if ($opt_n) { + print "$fname would be cleaned up\n" if $opt_v; + } else { + unslurp($fname, "$pre$newl1$newl2$body$newl3"); + print "$fname cleaned up\n" if $opt_v; + } + } + } + + preprocess($fname, $opt_n ? $oldg : $guard) + unless $fname =~ $exclude or $fname =~ $exclude_cpp; +} + +if (%old_guard) { + print STDERR "warning: guard symbol renaming may break things\n"; + for my $guard (sort keys %old_guard) { + print STDERR " $old_guard{$guard} -> $guard\n"; + } + print STDERR "To find uses that may have to be updated try:\n"; + print STDERR " git grep -Ew '", join("|", sort values %old_guard), + "'\n"; +} |