#!/usr/bin/perl -w

=head1 NAME

dh_shlibdeps - calculate shared library dependancies

=cut

use strict;
use Cwd;
use Debian::Debhelper::Dh_Lib;

=head1 SYNOPSIS

B<dh_shlibdeps> [S<I<debhelper options>>] [B<-L>I<package>] [B<-l>I<directory>] [B<-X>I<item>] [S<B<--> I<params>>]

=head1 DESCRIPTION

dh_shlibdeps is a debhelper program that is responsible for calculating
shared library dependancies for packages.

This program is merely a wrapper around L<dpkg-shlibdeps(1)> that calls it
once for each package listed in the control file, passing it
a list of ELF executables and shared libraries it has found.

=head1 OPTIONS

=over 4

=item B<-u>I<params>, B<--dpkg-shlibdeps-params=>I<params>

=item B<--> I<params>

Pass "params" to L<dpkg-shlibdeps(1)>.

=item B<-X>I<item>, B<--exclude=>I<item>

Exclude files that contain "item" anywhere in their filename from being
passed to dpkg-shlibdeps. This will make their dependancies be ignored.
This may be useful in some situations, but use it with caution. This option
may be used more than once to exclude more than one thing.

=item B<-l>I<directory>[:directory:directory:..]

Before dpkg-shlibdeps is run, LD_LIBRARY_PATH will have added to it the 
specified directory (or directories -- separate with colons). This is
useful for multi-binary packages where a library is built in one
package and another package contains binaries linked against said
library. Relative paths will be made absolute for the benefit of
dpkg-shlibdeps.

Note that the directory given should be the complete or relative path to
a directory that contains the library. See example below.

=item B<-L>I<package>, B<--libpackage=>I<package>

Use the shlibs file automatically generated by dh_makeshlibs for the named
package as a kind of automatically generated shlibs.local file. You can use
this switch in concert with the -l switch to make dpkg-shlibdeps find a
library built as part of the current package, and get the shlibs information.
See example below.

=back

=head1 EXAMPLES

Suppose that your source package produces libfoo1, libfoo-dev, and
libfoo-bin binary packages. libfoo-bin links against libfoo1, and should
depend on it. In your rules file, first run dh_makeshlibs, then dh_shlibdeps:

	dh_makeshlibs
	dh_shlibdeps -L libfoo1 -l debian/libfoo1/usr/lib

This will have the effect of generating automatically a shlibs file for
libfoo1, and using that file and the libfoo1 library in the
debian/libfoo1/usr/lib directory to calculate shared library dependency
information.

=cut

init();

# Add directory to library search path.
if ($dh{L_PARAMS}) {
	my @paths=();
	# Add to existing paths, if set.
	push @paths, $ENV{'LD_LIBRARY_PATH'}
		if exists $ENV{'LD_LIBRARY_PATH'};
	foreach (split(/:/, $dh{L_PARAMS})) {
		# Force the path absolute.
		if (m:^/:) {
			push @paths, $_;
		}
		else {
			push @paths, getcwd()."/$_";
		}
	}
	$dh{L_PARAMS}=join(':', @paths);
	$ENV{'LD_LIBRARY_PATH'}=$dh{L_PARAMS};
	verbose_print("LD_LIBRARY_PATH=$dh{L_PARAMS}");
}

foreach my $package (@{$dh{DOPACKAGES}}) {
	my $tmp=tmpdir($package);
	my $ext=pkgext($package);

	my @filelist;
	my $ff;

	# Generate a list of ELF binaries in the package, ignoring any
	# we were told to exclude.
	my $find_options='';
	if (defined($dh{EXCLUDE_FIND}) && $dh{EXCLUDE_FIND} ne '') {
		$find_options="! \\( $dh{EXCLUDE_FIND} \\)";
	}
	foreach my $file (split(/\n/,`find $tmp -path $tmp/usr/lib/debug -prune -or -type f \\( -perm +111 -or -name "*.so*" \\) $find_options -print`)) {
		# TODO this is slow, optimize. Ie, file can run once on
		# multiple files..
		$ff=`file "$file"`;
		if ($ff=~m/ELF/ && $ff!~/statically linked/) {
			push @filelist,$file;
		}
	}

	if (@filelist) {
		my @opts;
		if (defined $dh{LIBPACKAGE} && length $dh{LIBPACKAGE}) {
			@opts=("-L".tmpdir($dh{LIBPACKAGE}."/DEBIAN/shlibs"));
		}
		doit("dpkg-shlibdeps","-Tdebian/${ext}substvars",
			@opts,@{$dh{U_PARAMS}},@filelist);
	}
}

=head1 SEE ALSO

L<debhelper(7)>

This program is a part of debhelper.

=head1 AUTHOR

Joey Hess <joeyh@debian.org>

=cut