#! /usr/bin/perl
#
# slxldd - OpenSLX-rewrite of ldd that works on multiple architectures.
#
# (c) 2006 - OpenSLX.com
#
# Oliver Tappe <ot@openslx.com>
#
use strict;
my $abstract = q[
slxldd
This script reimplements ldd in a way that should work for all
binary formats supported by the binutils installed on the host system.
An example: if you have a folder containing an ia64 system, you can
invoke this script on a ia32-host in order to determine all the libraries
required by a binary of the ia64 target system.
];
use File::Glob ':globally';
use Getopt::Long;
use Pod::Usage;
# add the lib-folder to perl's search path for modules:
use FindBin;
use lib "$FindBin::RealBin/../lib";
use OpenSLX::Basics;
my (
$helpReq,
$manReq,
$verbose,
$rootPath,
$versionReq,
@filesToDo,
@libFolders,
@libs,
%libInfo,
);
$rootPath = '/';
GetOptions(
'help|?' => \$helpReq,
'man' => \$manReq,
'root-path=s' => \$rootPath,
'verbose' => \$verbose,
'version' => \$versionReq,
) or pod2usage(2);
pod2usage(-msg => $abstract, -verbose => 0, -exitval => 1) if $helpReq;
pod2usage(-verbose => 2) if $manReq;
if ($versionReq) {
system('slxversion');
exit 1;
}
openslxInit();
if (!$rootPath) {
print STDERR _tr("You need to specify the root-path!\n");
pod2usage(2);
}
$rootPath =~ s[/+$][];
# remove trailing slashes
if (!@ARGV) {
print STDERR _tr("You need to specify at least one file!\n");
pod2usage(2);
}
fetchLoaderConfig();
foreach my $file (@ARGV) {
if ($file =~ m[^/]) {
# force absolute path relative to $rootPath:
$file = "$rootPath$file";
}
if (!-e $file) {
print STDERR _tr("slxldd: unable to find file '%s', skipping it\n", $file);
next;
}
push @filesToDo, $file;
}
foreach my $file (@filesToDo) {
addLibsForBinary($file);
}
sub fetchLoaderConfigFile
{
my $ldConfFile = shift;
open(LDCONF, "< $ldConfFile");
while(<LDCONF>) {
chomp;
if (/^\s*include\s+(.+?)\s*$/i) {
foreach my $incFile (<$rootPath$1>) {
fetchLoaderConfigFile($incFile);
}
next;
}
if (/\S+/i) {
s[=.+][];
# remove any lib-type specifications (e.g. '=libc5')
push @libFolders, "$rootPath$_";
}
}
close LDCONF;
}
sub fetchLoaderConfig
{
if (!-e "$rootPath/etc/ld.so.conf") {
die _tr("'%s' not found, maybe wrong root-path?\n", $rootPath/etc/ld.so.conf);
}
fetchLoaderConfigFile("$rootPath/etc/ld.so.conf");
# add "trusted" folders /lib and /usr/lib if not already in place:
if (!grep { m[^$rootPath/lib$]} @libFolders) {
push @libFolders, "$rootPath/lib";
}
if (!grep { m[^$rootPath/usr/lib$] } @libFolders) {
push @libFolders, "$rootPath/usr/lib";
}
}
sub addLib
{
my $lib = shift;
my $bitwidth = shift;
my $rpath = shift;
if (!exists $libInfo{$lib}) {
push @libs, $lib;
my $libPath;
my @folders = @libFolders;
if (defined $rpath) {
# add rpath if given (explicit paths set during link stage)
push @folders, split ':', $rpath;
}
foreach my $folder (@folders) {
if (-e "$folder/$lib") {
# have library matching name, now check if the platform is ok, too:
my $libFileInfo = `file --dereference $folder/$lib 2>/dev/null`;
if ($?) {
die _tr("unable to fetch file info for '%s', giving up!\n",
$folder/$lib);
}
my $libBitwidth = ($libFileInfo =~ m[64-bit]i) ? 64 : 32;
if ($bitwidth != $libBitwidth) {
vlog 0, _tr('%s has wrong bitwidth (%s instead of %s)',
"$folder/$lib", $libBitwidth, $bitwidth) if $verbose;
next;
}
$libPath = "$folder/$lib";
last;
}
}
if (!defined $libPath) {
die _tr("*** unable to find lib %s! ***\n", $lib);
}
print "$libPath\n";
$libInfo{$lib} = $libPath;
push @filesToDo, $libPath;
}
}
sub addLibsForBinary
{
my $binary = shift;
# first do some checks:
print STDERR _tr("analyzing '%s'...\n", $binary) if $verbose;
my $fileInfo = `file --dereference --brief --mime $binary 2>/dev/null`;
chomp $fileInfo;
print STDERR _tr("\tinfo is: '%s'...\n", $fileInfo) if $verbose;
if ($?) {
die _tr("unable to fetch file info for $binary, giving up!\n");
}
if ($fileInfo !~ m[^application/(x-executable|x-shared)]i) {
# ignore anything that's not an executable or a shared library
print STDERR _tr("%s: ignored, as it isn't an executable or a shared library\n", $binary);
next;
}
my $bitwidth = ($fileInfo =~ m[64-bit]i) ? 64 : 32;
# determine whether binary is 32- or 64-bit platform
# now find out about needed libs, we first try objdump...
if ($verbose) {
print STDERR _tr("\ttrying objdump...\n");
}
my $res = `objdump -p $binary 2>/dev/null`;
if (!$?) {
# find out if rpath is set for binary:
my $rpath;
if ($res =~ m[^\s*RPATH\s*(\S+)]im) {
$rpath = $1;
if ($verbose) {
print STDERR _tr("\trpath='%s'\n", $rpath);
}
}
while($res =~ m[^\s*NEEDED\s*(.+?)\s*$]gm) {
addLib($1, $bitwidth, $rpath);
}
} else {
# ...objdump failed, so we try readelf instead:
if ($verbose) {
print STDERR _tr("\ttrying readelf...\n");
}
$res = `readelf -d $binary 2>/dev/null`;
if ($?) {
die _tr("neither objdump nor readelf seems to be installed, giving up!\n");
}
# find out if rpath is set for binary:
my $rpath;
if ($res =~ m/Library\s*rpath:\s*\[([^\]]+)/im) {
$rpath = $1;
if ($verbose) {
print STDERR _tr("\trpath='%s'\n", $rpath);
}
}
while($res =~ m{\(NEEDED\)[^\[]+\[(.+?)\]\s*$}gm) {
addLib($1, $bitwidth, $rpath);
}
}
}
__END__
=head1 NAME
slxldd - OpenSLX-script to determine the libraries required by any given
binary file.
=head1 SYNOPSIS
slxldd [options] file [...more files]
Options:
--help brief help message
--man show full documentation
--root-path=<string> path to the root folder for library search
--verbose show what's going on during execution
--version show version
=head1 OPTIONS
=over 8
=item B<--help>
Prints a brief help message and exits.
=item B<--man>
Prints the manual page and exits.
=item B<--root-path=<string>>
Sets the root folder that is used when searching for libraries. In order to
collect the loader-settings, etc/ld.so.conf is read relative to this path and
all libraries are sought relative to this path, too (a.k.a. a virtual chroot).
Defaults to '/'.
=item B<--verbose>
Prints info about the files as they are being scanned.
=item B<--version>
Prints the version and exits.
=back
=cut
