Current Path : /usr/bin/ |
Current File : //usr/bin/dh_dwz |
#!/usr/bin/perl =head1 NAME dh_dwz - optimize DWARF debug information in ELF binaries via dwz =cut use strict; use warnings; use File::Find; use Debian::Debhelper::Dh_Lib; our $VERSION = DH_BUILTIN_VERSION; =head1 SYNOPSIS B<dh_dwz> [S<I<debhelper options>>] [B<-X>I<item>] [S<B<--> I<params>>] =head1 DESCRIPTION B<Caveat>: This tool is experimental and may disappear or change behaviour without any notice. B<dh_dwz> is a debhelper program that will optimize the (uncompressed) size of the DWARF debug information in ELF binaries. It does so by running L<dwz(1)> on all the ELF binaries in the package. =head1 OPTIONS =over 4 =item B<-X>I<item>, B<--exclude=>I<item> Exclude files that contain I<item> anywhere in their filename from being stripped. You may use this option multiple times to build up a list of things to exclude. =item B<--> I<params> Pass I<params> to L<dwz(1)> when it processes ELF binaries. This is mostly useful for setting memory related parameters (e.g. -l and -L). =back =head1 NOTES If the B<DEB_BUILD_OPTIONS> environment variable contains B<nostrip>, nothing will be stripped, in accordance with Debian policy (section 10.1 "Binaries"). While this tool technically does not remove debug information from binaries, it is still skipped when the B<DEB_BUILD_OPTIONS> environment variable contains B<nostrip>. This is because B<nostrip> is often used to optimize build times (e.g. for "build and test"-cycles) rather than optimizing for size. =cut init(); # This variable can be used to turn off stripping (see Policy). exit 0 if get_buildoption('nostrip'); warning('This tool is experimental and may change (or be retired) without any notice'); my @elf_files; sub testfile { my $fn = $_; return if -l $fn; # Always skip symlinks. # See if we were asked to exclude this file. # Note that we have to test on the full filename, including directory. if (excludefile($fn)) { $File::Find::prune = 1 if -d _; return; } return if -d _; # Do not process output files from dwz return if index($fn, '/debug/.dwz/') > -1; if (is_so_or_exec_elf_file($fn)) { push(@elf_files, $fn); } return; } for my $package (@{$dh{DOPACKAGES}}) { my $tmp = tmpdir($package); next if not -d $tmp; @elf_files = (); find({ wanted => \&testfile, no_chdir => 1, }, $tmp); next if not @elf_files; # Consistent order; @elf_files = sort(@elf_files); my ($unique_files, $hardlinks) = find_hardlinks(@elf_files); # TODO: Support multifile (-m) xargs($unique_files, 'dwz', '-q', @{$dh{U_PARAMS}}, '--'); # Now change over any files we can that used to be hard links so # they are again. for my $hardlink (keys %{$hardlinks}) { my $target = $hardlinks->{$hardlink}; # Remove old file. rm_files($hardlink); # Make new hardlink. doit('ln', '-f', $target, $hardlink); } } =head1 SEE ALSO L<debhelper(7)> This program is a part of debhelper. =head1 AUTHOR Niels Thykier <niels@thykier.net> =cut