#!/usr/bin/perl -w

=head1 NAME

dh_dkms - correctly handle DKMS usage by a kernel module package

=cut

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

=head1 SYNOPSIS

B<dh_dkms> [S<I<debhelper options>>] [S<B<-l>>] [S<B<-V>[I<version>]>] [S<B<--> I<file>>]

=head1 DESCRIPTION

dh_dkms is a debhelper program that is responsible for correctly setting
postinst, postrm and dependencies in kernel module packages using DKMS.

If a file named debian/package.dkms exists, then different actions are
performed, depending on its contents.

=head1 FILES

=over 4

=item debian/I<package>.dkms

=item debian/dkms

It can be a proper configuration file, and in this case it would be installed
in the proper directory as dkms.conf.

It can also point to another file (this should be used when the configuration
is provided by upstream), and in this case that file will be installed as dkms.conf
in the proper directory.

This file can only miss if a filename is provided when calling dh_dkms.

=back

=head1 OPTIONS

=over 4

=item B<-l>, B<--legacy>

Add code to also support DKMS versions < 2.1.0.0.

=item B<-V>, B<-V> I<version>

If C<PACKAGE_VERSION> in F<dkms.conf> is set to C<#MODULE_VERSION#>, set it to
the given I<version> or, if none is given, default to the upstream version of
the current package. Otherwise, leave the value specified in F<dkms.conf>.

=item B<--> I<file>

Don't look for debian/I<package>.dkms or debian/dkms, but install I<file> as dkms.conf.

=back

=head1 NOTES

Note that this command is not idempotent. L<dh_prep(1)> should be called
between invocations of this command. Otherwise, it may cause multiple
instances of the same text to be added to maintainer scripts.

=cut

# placeholder substituted at build time
# is shown along generated autoscripts
#VERSION#

init(options => {
	"l|legacy" => \$dh{LEGACY_DKMS},
});

foreach my $package (@{$dh{DOPACKAGES}}) {
	#next if is_udeb($package);

	my $tmp = tmpdir($package);
	my $dkms_dir = "/usr/lib/dkms/";
	my $dkms_conf = pkgfile($package, "dkms");
	my $is_snippet = 0;
	my @other_conf;
	my $name;
	my $package_name;
	my $package_version;
	my $build_exclusive_config;

	if ($dkms_conf) {
		# let's see if it's a proper snippet
		open(IN, "< $dkms_conf");
		while (my $l = <IN>) {
			$l =~ /PACKAGE_NAME=(["'])(.*)\1/ && ($is_snippet = 1);
		}
		close(IN);

		if ($is_snippet) {
			$name = $dkms_conf;
		}
		else {
			my @search_dirs = ($dh{SOURCEDIR} // '.', default_sourcedir($package));
			@other_conf = filearray($dkms_conf, \@search_dirs);
			if ($#other_conf > 1) {
				error "cannot list more than one file in $dkms_conf!";
			}
			else {
				$name = $other_conf[0];
			}
		}
	}
	elsif ($#ARGV == 0) {
		$name = $ARGV[0];
	}
	else {
		next;
	}
	verbose_print "installing $name as dkms.conf";

	# now, parse our configuration file
	open(IN, "< $name") || error("cannot read $name: $!");
	while (my $l = <IN>) {
		$l =~ /PACKAGE_NAME=(["']?)(.*)\1/ && ($is_snippet = 1 && $package_name = $2);
		$l =~ /PACKAGE_VERSION=(["']?)(.*)\1/ && ($package_version = $2);
		$l =~ /BUILD_EXCLUSIVE_CONFIG=(["']?)(.*)\1/ && ($build_exclusive_config = $2);
		$l =~ /BUILD_EXCLUSIVE_KERNEL_MIN=(["']?)(.*)\1/ && ($build_exclusive_config = "yes");
		$l =~ /BUILD_EXCLUSIVE_KERNEL_MAX=(["']?)(.*)\1/ && ($build_exclusive_config = "yes");
	}
	close(IN);

	#$ENV{DH_AUTOSCRIPTDIR} = "debian/scripts/";
	if ($build_exclusive_config) {
		addsubstvar($package, "misc:Depends", "dkms", ">= 3.0.11");
	}
	elsif ($dh{LEGACY_DKMS}) {
		doit("install", "-p", "-D", "-m755", "$dkms_dir/common.postinst", "$tmp/usr/share/$package/postinst");
		addsubstvar($package, "misc:Depends", "dkms");
	}
	else {
		addsubstvar($package, "misc:Depends", "dkms", ">= 2.1.0.0");
	}

	if ($dh{V_FLAG_SET} || $package_version eq "#MODULE_VERSION#") {
		$package_version = $dh{V_FLAG} || "";
		if ($package_version eq "") {
			# Call isnative because it sets $dh{VERSION}
			# as a side effect.
			isnative($package);
			$package_version = $dh{VERSION};
			# Remove the Debian revision
			$package_version =~ s/-[^-]+$//;
			# Remove the Debian epoch
			$package_version =~ s/^\d+://;
		}

		my $old_name = $name;
		$name = "debian/".pkgext($package)."dkms.debhelper";
		doit("cp", "-a", $old_name, $name);
		doit("sed", "-i", "s/#MODULE_VERSION#/$package_version/g", $name);
	}

        error "could not determine package name"
          unless defined($package_name);

        error "could not determine package version"
          unless defined($package_version);

        error "invalid package version '$package_version'"
          unless $package_version =~ /^[-+.~:0-9a-zA-Z]+$/;

	autoscript($package, "prerm", "prerm-dkms",
	    "s/#MODULE_NAME#/$package_name/;s/#MODULE_VERSION#/$package_version/");
	autoscript($package, "postinst", "postinst-dkms",
	    "s/#MODULE_NAME#/$package_name/;s/#MODULE_VERSION#/$package_version/");
	doit("install", "-p", "-D", "-m644", "$name", "$tmp/usr/src/$package_name-$package_version/dkms.conf");
}

=head1 SEE ALSO

L<debhelper(1)>

This program is part of the Debian DKMS package.

L<dkms(8)>

=head1 AUTHOR

David Paleino <dapal@debian.org>

=cut