memalign.pm

# Copyright (C) 2001-2009, Parrot Foundation.

=head1 NAME

config/auto/memalign.pm - Memory Alignment

=head1 DESCRIPTION

Determines if the C library supports C<memalign()>.

=cut

package auto::memalign;

use strict;
use warnings;

use base qw(Parrot::Configure::Step);

use Parrot::Configure::Utils ':auto';


sub _init {
    my $self = shift;
    my %data;
    $data{description} = q{Does your C library support memalign};
    $data{result}      = q{};
    return \%data;
}

sub runstep {
    my ( $self, $conf ) = @_;

    if ( defined $conf->data->get('memalign') ) {

        # already set; leave it alone
        $self->set_result('already set');
        return 1;
    }
    my $test = 0;

    _set_malloc_header($conf);

    _set_ptrcast($conf);

    $conf->cc_gen('config/auto/memalign/test_c.in');
    eval { $conf->cc_build(); };
    unless ( $@ || $conf->cc_run_capture() !~ /ok/ ) {
        $test = 1;
    }
    $conf->cc_clean();

    my $test2 = 0;

    $conf->cc_gen('config/auto/memalign/test2_c.in');
    eval { $conf->cc_build(); };
    unless ( $@ || $conf->cc_run_capture() !~ /ok/ ) {
        $test2 = 1;
    }
    $conf->cc_clean();

    $self->_set_memalign($conf, $test, $test2);

    return 1;
}

sub _set_malloc_header {
    my $conf = shift;
    if ( $conf->data->get('i_malloc') ) {
        $conf->data->set( malloc_header => 'malloc.h' );
    }
    else {
        $conf->data->set( malloc_header => 'stdlib.h' );
    }
}

sub _set_ptrcast {
    my $conf = shift;

    my $ptrsize = $conf->data->get('ptrsize');
    my $ptrcast = $conf->data->get("int${ptrsize}_t");

    # FIXME: find out if this actually does the right thing if intXX_t is
    # not available
    if ( defined $ptrcast ) {}
    elsif ( $ptrsize == $conf->data->get('intsize') ) {
        $ptrcast = 'int';
    }
    elsif ( $ptrsize == $conf->data->get('longsize') ) {
        $ptrcast = 'long';
    }
    elsif ( $ptrsize == $conf->data->get('longlongsize') ) {
        $ptrcast = 'long long';
    }
    else {
        # TODO: fail properly
    }

    $conf->data->set( ptrcast => $ptrcast );
}

sub _set_memalign {
    my $self = shift;
    my ($conf, $test, $test2) = @_;
    $conf->data->set( malloc_header => undef );

    my $f =
          $test2 ? 'posix_memalign'
        : $test  ? 'memalign'
        :          '';
    $conf->data->set( memalign => $f );
    my $test_str = $test ? " (Yep:$f) " : " (no) ";
    $conf->debug($test_str);
    $self->set_result( $test ? 'yes' : 'no' );
}

1;

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