sudo/scripts/unanon

51 lines
1.2 KiB
Perl
Executable File

#!/usr/bin/env perl
#
# Post-process files generated by protoc-c to remove anonymous unions.
# Works on the generated files but probably little else.
use warnings;
use strict;
sub unanon {
my $hfile = shift;
my $cfile = shift;
my ($fh, $content);
my %members;
open $fh, "<", $hfile or die $!;
local $/; # enable localized slurp mode
$content = <$fh>;
close $fh;
# Detect and replace anonymous unions in .h file.
# Assumes there is only one anonymous union in scope.
while ($content =~ s/^(struct\s+(\w+)[^}]+)(union\s+{([^}]+)}\s*);/$1$3 u;/sm) {
my $s = $2;
my $u = $4;
$u =~ s:/\*((?!\*/).)*\*/::sg;
foreach (split(/\n+/, $u)) {
if (/^.*\s+\**([^;]+);/) {
$members{$1} = $s;
}
}
}
open $fh, ">", $hfile or die $!;
print $fh $content;
close $fh;
# Replace anonymous union access in generated .c file.
open $fh, "<", $cfile or die $!;
$content = <$fh>;
close $fh;
while (my ($key, $val) = each %members) {
# We only support access via offsetof()
$content =~ s/offsetof\($val, $key\)/offsetof($val, u.$key)/g;
}
open $fh, ">", $cfile or die $!;
print $fh $content;
close $fh;
}
unanon(@ARGV);