#!/usr/bin/perl -w

=head1 NAME

dh_illumos_gate - unpack and prepare illumos sources

=cut

use strict;
use Debian::Debhelper::Dh_Lib;
use Dpkg::Changelog::Parse;
use Cwd;

=head1 SYNOPSIS

B<dh_illumos_gate> [S<I<debhelper options>>] [B<-B>] [B<-X>I<PATTERN>]
[files and/or directories to extract]

=head1 DESCRIPTION

C<dh_illumos_gate> is responsible for unpacking illumos sources and adjusting the sources
for Debian build environment (paths to programs, command options, linker and compiler flags, etc.).

C<dh_illumos_gate> extracts given files or directories, if any.
Otherwise it extracts entire F<illumos-gate/usr/>.
In any case B<-X> option can be used to exclude some files or directories,
and top directory F<illumos-gate> is always stripped..

If files interested to C<dh_illumos_gate> are unpacked they will be configured.
See L</DETAILS>.

After executing C<dh_illumos_gate> one can use commands like this to configure or build
components of illumos gate:

    ksh93 usr/bldenv.sh usr/env.sh -c "cd usr/src/lib/libzfs && make --sun install"

L<dh_illumos_make(1)> provides more convenient way to do this.

=head1 OPTIONS

=over 4

=item B<-B> B<--build>

Extract files known to be required for building illumos components.
These are F<usr/src/tools/scripts/bldenv.sh>, F<usr/src/Makefile*>,
F<usr/src/common/mapfiles/*>. This option is provided only for convenience.
You are free to extract these files explicitly.

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

Do not extract files or directories matching I<PATTERN>. 
This option can be used multiple times. I<PATTERN> is passed
as is to L<tar(1)> via I<--exclude=PATTERN>.

=back

=head1 EXAMPLES

=over 4

=item Unpack and configure the whole illumos source tree (F<usr/>)

    dh_illumos_gate

=item Unpack and configure whole illumos source tree, but F<usr/src/uts/>

    dh_illumos_gate -X usr/src/uts

=item Unpack and configure whole illumos source tree, but F<usr/src/uts/>;
then add F<usr/src/uts/common/sys/>

    dh_illumos_gate -X usr/src/uts
    dh_illumos_gate usr/src/uts/common/sys

=item Unpack all Makefiles under F<usr/src/>

    dh_illumos_gate usr/src/Makefile\*

=back

=head1 FILES

=over 4

=item /usr/src/illumos-gate/illumos-gate-$(VER).tar.xz

This file contains complete and unmodified illumos sources.
It is provided by package I<illumos-source-$(VER)>.

Version C<$(VER)> is determined from F<debian/changelog>:

    (\d+\.\d+).* => \1, e. g.:
    2.10+3       => VER = 2.10

=back

=head1 DETAILS

Here are things which this helper does after unpacking illumos sources.

=over 4

=cut

init(options => { 
	"build|B" => \$dh{BUILD},
    });

my %options = (file => 'debian/changelog');
my $changelog = changelog_parse(%options);
my $version = $changelog->{'Version'};

my $VER;
if ($version =~ /^(\d+\.\d+).*$/) {
    $VER = $1;
} else {
    error("Could not determine illumos source version from changelog. "
        ."It should be like 2.10+1, but it is '$version'");
}
my $tarball = "/usr/src/illumos-gate/illumos-gate-$VER.tar.xz";

if (! -f $tarball) {
    error("$tarball does not exist. You might not have package illumos-source-$VER "
    ."installed or have a typo in debian/changelog");
}

my @tar_X = ();
if (defined($dh{'EXCLUDE'}) && $dh{'EXCLUDE'}) {
    foreach my $x (@{$dh{'EXCLUDE'}}) {
        push @tar_X, '--exclude';
        push @tar_X, $x;
    }
}

my @to_extract = ();
if (@ARGV) {
    if ($dh{'BUILD'}) {
        push @to_extract, (
            'usr/src/Makefile*',
            'usr/src/common/mapfiles',
            'usr/src/tools/scripts/bldenv.sh',
        );
    }
    push @to_extract, map {m,(?:illumos-gate/)?(.*),; $1} @ARGV;
} else {
    push @to_extract, 'usr';
}

doit('tar', '-x', '-f', $tarball, @tar_X, '--wildcards', '--strip-components=1',
    map {'illumos-gate/' . $_} @to_extract);

=item Saving original files

Any files from illumos sources, changed by this helper,
are saved with F<.orig> suffix, so you can investigate changes.
For example, you can use C<diff -dub usr/src/Makefile.master.orig usr/src/Makefile.master>
to see all changes.

=cut

=item Changes to F<usr/src/Makefile.master> (if extracted):

Remove option C<-s> (strip) from install command for directories and files.
This options does not make sense for directories and GNU L<install(1)> is
not tolerant here. Also replace option C<-f> with C<-t>.

Set C<i386_XARCH> to C<-m32> since native host compiler can produce 64-bit
code by default.

Explicitly undefine some CPP macros related to amd64 for building 32-bit
objects, e. i. options like C<-U__amd64__> are appended to C<i386_XARCH>
and C<i386_AS_XARCH>.

=cut

my $multiarch = `dpkg-architecture -qDEB_HOST_MULTIARCH`;
chomp $multiarch;
my $bits = `dpkg-architecture -qDEB_HOST_ARCH_BITS`;
chomp $bits;

# In illumos source 32-bit binaries are default
my ($libdir32, $libdir64, $usrlibdir32, $usrlibdir64);

if ($bits == 64) {
    $libdir32    = "lib32";
    $usrlibdir32 = "usr/$libdir32";
    $libdir64    = "lib/$multiarch";
    $usrlibdir64 = "usr/$libdir64";
} else {
    $libdir32    = "lib/$multiarch";
    $usrlibdir32 = "usr/$libdir32";
    $libdir64    = "lib64";
    $usrlibdir64 = "usr/$libdir64";
}

my $Makefile_master = 'usr/src/Makefile.master';
my $Makefile_master_orig = $Makefile_master . '.orig';
if (-f $Makefile_master) {
    if (! -e $Makefile_master_orig) {
        doit('cp', '-f', $Makefile_master, $Makefile_master_orig);
    }

    # Be carefull with modern CPP:
    my $i386_undef = '-Uamd64 -U__amd64 -U__amd64__ -U__x86_64__ -U__x86_64 -U_LP64';
    doit('sed', '-r', '-i', '
        /^INS\.(file|dir)/ s, -s,,;
        /^INS\.file/ s, -f, -t,;
        s,^i386_XARCH\s*=.*,i386_XARCH=  -m32 ' . $i386_undef . ',;
        s,^i386_AS_XARCH\s*=.*,i386_AS_XARCH= ' . $i386_undef . ',;
        ', $Makefile_master
    );
}


=item Changes to F<usr/src/lib/Makefile.lib> (if extracted):

Append C<CFLAGS> to C<BUILD.SO> command, because C<BUILD.SO>
by default uses C compiler to create shared library.

Set C<ROOTLIBDIR>, C<ROOTLIBDIR64>, C<ROOTFS_LIBDIR> and C<ROOTLIBDIR64>
to match Debian multiarch layout. For example C<ROOTLIBDIR64> =
F</usr/lib/x86_64-illumos> and C<ROOTFS_LIBDIR> = F</lib32> on I<illumos-amd64>.
It cannot be done in environment file F<env.sh> (see below), because
in some cases C<ROOTLIBDIR> will be overriden by C<ROOTFS_LIBDIR> within makefiles.

=cut

my $Makefile_lib = 'usr/src/lib/Makefile.lib';
my $Makefile_lib_orig = $Makefile_lib . '.orig';
if (-f $Makefile_lib) {
    if (! -e $Makefile_lib_orig) {
        doit('cp', '-f', $Makefile_lib, $Makefile_lib_orig);
    }
    doit('sed', '-r', '-i', '
        /^BUILD.SO/ s,\$\(CC\),$(CC) $(CFLAGS),;
        ', $Makefile_lib
    );
    doit('sed', '-r', '-i', "
        s,^(ROOTFS_LIBDIR)\\s*=.*,\\1=\$(ROOT)/$libdir32,;
        s,^(ROOTFS_LIBDIR64)\\s*=.*,\\1=\$(ROOT)/$libdir64,;
        s,^(ROOTLIBDIR)\\s*=.*,\\1=\$(ROOT)/$usrlibdir32,;
        s,^(ROOTLIBDIR64)\\s*=.*,\\1=\$(ROOT)/$usrlibdir64,;
        ", $Makefile_lib
    );
}

=item Create F<usr/env.sh> (if F<usr> exists and F<usr/env.sh> does not)

Set C<CODEMGR_WS> to the current directry.

Set C<VERSION> from F<./debian/changelog>.
For example it can be C<2.10-3>.

Set C<LD_ALTEXEC>=F</usr/bin/ld-gnu-to-sun> to call L<sunld(1)>
instead of GNU L<ld(1)>. Default system GCC is build to use GNU L<ld(1)>,
but L<sunld(1)> is required to build most illumos components.
See L<ld-gnu-to-sun(1)>.

Set proto area to be F<./debian/tmp>.

Disable linting libraries by replacing C<LINT> with ":".
So it will do nothing. Successfully. Also define C<LINTLIB> to empty
string to prevent installation of lint libraries (which do not exist).

Disable modifying comment section of ELFs by replacing C<MCS> with ":".

Disable stripping by replacing C<STRIP> with ":".

Enable GCC and GCC4 mode by defining C<__GNUC> and C<__GNUC4>.

Change GCC root to F</usr>, so the default system compiler is used.

Define C<LEX> to be C</usr/bin/flex -l>.

Export all C<DEB_*> variables (using C<dpkg-architecture -s>)
to make them available from makefiles.

=cut


if ( -d 'usr' && ! -f 'usr/env.sh') {
    my $cwd = getcwd();
    my $env = 'usr/env.sh';
    my $mach = `uname -p`; chomp $mach;
    if (open (ENV, '>', $env)) {
        print ENV "# This file was generated by dh_illumos_gate(1)\n";
        print ENV "export VERSION='$version'\n";
        print ENV "export CODEMGR_WS='$cwd'\n";
        print ENV "export ROOT='$cwd/debian/tmp'\n";
        print ENV "export SRC='$cwd/usr/src'\n";
        print ENV "export MULTI_PROTO='no'\n";
        print ENV "export CW_NO_SHADOW=1\n";
        print ENV "export LD_ALTEXEC='/usr/bin/ld-gnu-to-sun'\n";
        print ENV "export BUILD_TOOLS='/opt'\n";
        print ENV "export MACH='$mach'\n";
        print ENV "export LINT=:\n";
        print ENV "export LINTLIB=''\n";
        print ENV "export __GNUC=''\n";
        print ENV "export __GNUC4=''\n";
        print ENV "export GCC_ROOT='/usr'\n";
        print ENV "export LEX='/usr/bin/flex -l'\n";
        print ENV "export STRIP=':'\n";
        print ENV "export MCS=':'\n";
        print ENV "export DEB_LIBDIR_32='/$libdir32'\n";
        print ENV "export DEB_USRLIBDIR_32='/$usrlibdir32'\n";
        print ENV "export DEB_LIBDIR_64='/$libdir64'\n";
        print ENV "export DEB_USRLIBDIR_64='/$usrlibdir64'\n";
        print ENV "export LDLIBS32=\"-YP,\$ROOT/\$DEB_LIBDIR_32:\$ROOT/\$DEB_USRLIBDIR_32\"\n";
        print ENV "export LDLIBS64=\"-YP,\$ROOT/\$DEB_LIBDIR_64:\$ROOT/\$DEB_USRLIBDIR_64\"\n";
        print ENV 'export LDLIBS_NATIVE="', ($bits == 64) ? '$LDLIBS64' : '$LDLIBS32', "\"\n";
        print ENV `dpkg-architecture -s`;

        close(ENV);
    } else {
        error("Failed to write `$env': $!");
    }
}

=item Create F<usr/bldenv.sh> (if not exists and F<usr/src/tools/scripts/bldenv.sh> extracted)

Copy F<usr/src/tools/scripts/bldenv.sh>
to F<usr/bldenv.sh>.

Fix definition of C<CTF*> variables, so this script will
not override them if they are already defined. These variables
can be set to ":", when executing L<dh_illumos_make(1)>
with option C<--without-ctf>.

=cut

my $bldenv_sh = 'usr/src/tools/scripts/bldenv.sh';
if (-f $bldenv_sh && ! -f 'usr/bldenv.sh') {
    doit('cp', '-f', $bldenv_sh, 'usr/bldenv.sh');
    doit('sed', '-r', '-i', '
        s,export +(CTF.+)="(.+)",export \1="${\1:-\2}",;
        ', 'usr/bldenv.sh'
    );
}
=back

=head1 NOTES

To clean package (via C<./debian/rules clean>) you should just remove F<usr/> directory:

    rm -rf usr


=head1 SEE ALSO

L<debhelper(7)>, L<dh_illumos_make(1)>.

=head1 AUTHOR

Igor Pashev <pashev.igor@gmail.com>

=cut