Alien-Base

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lib/Alien/Base.pm  view on Meta::CPAN

package Alien::Base;

use strict;
use warnings;

our $VERSION = '0.042';

use Carp;
use File::ShareDir ();
use File::Spec;
use Scalar::Util qw/blessed/;
use Capture::Tiny 0.17 qw/capture_merged/;
use Text::ParseWords qw/shellwords/;

=encoding UTF-8

=head1 NAME

Alien::Base - Base classes for Alien:: modules

=head1 SYNOPSIS

 package Alien::MyLibrary;

 use strict;
 use warnings;

 use parent 'Alien::Base';

 1;

(for details on the C<Makefile.PL> or C<Build.PL> and L<alienfile>
that should be bundled with your L<Alien::Base> subclass, please see
L<Alien::Base::Authoring>).

Then a C<MyLibrary::XS> can use C<Alien::MyLibrary> in its C<Build.PL>:

 use Alien::MyLibrary;
 use Module::Build 0.28; # need at least 0.28
 
 my $builder = Module::Build->new(
   ...
   extra_compiler_flags => Alien::MyLibrary->cflags,
   extra_linker_flags   => Alien::MyLibrary->libs,
   ...
 );
 
 $builder->create_build_script;

Or if you prefer L<ExtUtils::MakeMaker>, in its C<Makefile.PL>:

 use Alien::MyLibrary
 use ExtUtils::MakeMaker;
 use Config;
 
 WriteMakefile(
   ...
   CCFLAGS => Alien::MyLibrary->cflags . " $Config{ccflags}",
   LIBS   => ALien::MyLibrary->libs,
   ...
 );

Or if you are using L<ExtUtils::Depends>:

 use ExtUtils::MakeMaker;
 use ExtUtils::Depends;
 my $eud = ExtUtils::Depends->new(qw( MyLibrary::XS Alien::MyLibrary ));
 WriteMakefile(
   ...
   $eud->get_makefile_vars
 );

lib/Alien/Base.pm  view on Meta::CPAN

  # Sanity check in order to ensure that dist_dir can be found.
  # This will throw an exception otherwise.  
  $class->dist_dir;

  # get a reference to %Alien::MyLibrary::AlienLoaded
  # which contains names of already loaded libraries
  # this logic may be replaced by investigating the DynaLoader arrays
  my $loaded = do {
    no strict 'refs';
    no warnings 'once';
    \%{ $class . "::AlienLoaded" };
  };

  my @libs = $class->split_flags( $class->libs );

  my @L = grep { s/^-L// } @libs;
  my @l = grep { /^-l/ } @libs;

  unshift @DynaLoader::dl_library_path, @L;

  my @libpaths;
  foreach my $l (@l) {
    next if $loaded->{$l};

    my $path = DynaLoader::dl_findfile( $l );
    unless ($path) {
      carp "Could not resolve $l";
      next;
    }

    push @libpaths, $path;
    $loaded->{$l} = $path;
  }

  push @DynaLoader::dl_resolve_using, @libpaths;

  my @librefs = map { DynaLoader::dl_load_file( $_, 0x01 ) } grep !/\.(a|lib)$/, @libpaths;
  push @DynaLoader::dl_librefs, @librefs;

}

=head1 METHODS

In the example snippets here, C<Alien::MyLibrary> represents any
subclass of L<Alien::Base>.

=head2 dist_dir

 my $dir = Alien::MyLibrary->dist_dir;

Returns the directory that contains the install root for
the packaged software, if it was built from install (i.e., if
C<install_type> is C<share>).

=cut

sub dist_dir {
  my $class = shift;

  my $dist = blessed $class || $class;
  $dist =~ s/::/-/g;

  my $dist_dir = 
    $class->config('finished_installing') 
      ? File::ShareDir::dist_dir($dist) 
      : $class->config('working_directory');

  croak "Failed to find share dir for dist '$dist'"
    unless defined $dist_dir && -d $dist_dir;

  return $dist_dir;
}

sub new { return bless {}, $_[0] }

sub _flags
{
  my($class, $key) = @_;
  
  my $config = $class->runtime_prop;
  my $flags = $config->{$key};

  my $prefix = $config->{prefix};
  $prefix =~ s{\\}{/}g if $^O =~ /^(MSWin32|msys)$/;
  my $distdir = $config->{distdir};
  $distdir =~ s{\\}{/}g if $^O =~ /^(MSWin32|msys)$/;
  
  if($prefix ne $distdir)
  {
    $flags = join ' ', map { 
      s/^(-I|-L|-LIBPATH:)?\Q$prefix\E/$1$distdir/;
      s/(\s)/\\$1/g;
      $_;
    } $class->split_flags($flags);
  }
  
  $flags;
}

=head2 cflags

 my $cflags = Alien::MyLibrary->cflags;

 use Text::ParseWords qw( shellwords );
 my @cflags = shellwords( Alien::MyLibrary->cflags );

Returns the C compiler flags necessary to compile an XS
module using the alien software.  If you need this in list
form (for example if you are calling system with a list
argument) you can pass this value into C<shellwords> from
the Perl core L<Text::ParseWords> module.

=cut

sub cflags {
  my $class = shift;
  return $class->runtime_prop ? $class->_flags('cflags') : $class->_pkgconfig_keyword('Cflags');
}

sub cflags_static {
  my $class = shift;
  return $class->runtime_prop ? $class->_flags('cflags_static') : $class->_pkgconfig_keyword('Cflags', 'static');
}

=head2 libs

 my $libs = Alien::MyLibrary->libs;

 use Text::ParseWords qw( shellwords );
 my @cflags = shellwords( Alien::MyLibrary->libs );

Returns the library linker flags necessary to link an XS
module against the alien software.  If you need this in list
form (for example if you are calling system with a list

lib/Alien/Base.pm  view on Meta::CPAN

    # if pkg-config fails for whatever reason, then we try to
    # fallback on alien_provides_*
    $pcdata = '' if $! || $?;

    $pcdata =~ s/\s*$//;

    if($self->config('system_provides')) {
      if(my $system_provides = $self->config('system_provides')->{$keyword}) {
        $pcdata = length $pcdata ? "$pcdata $system_provides" : $system_provides;
      }
    }

    return $pcdata;
  }

  # use parsed info from build .pc file
  my $dist_dir = $self->dist_dir;
  my @pc = $self->_pkgconfig(@_);
  my @strings =
    grep defined,
    map { $_->keyword($keyword, 
      #{ pcfiledir => $dist_dir }
    ) }
    @pc;

  if(defined $self->config('original_prefix') && $self->config('original_prefix') ne $self->dist_dir)
  {
    my $dist_dir = $self->dist_dir;
    $dist_dir =~ s{\\}{/}g if $^O eq 'MSWin32';
    my $old = quotemeta $self->config('original_prefix');
    @strings = map {
      s{^(-I|-L|-LIBPATH:)?($old)}{$1.$dist_dir}e;
      s/(\s)/\\$1/g;
      $_;
    } map { $self->split_flags($_) } @strings;
  }

  return join( ' ', @strings );
}

sub _pkgconfig {
  my $self = shift;
  my %all = %{ $self->config('pkgconfig') };

  # merge in found pc files
  require File::Find;
  my $wanted = sub {
    return if ( -d or not /\.pc$/ );
    require Alien::Base::PkgConfig;
    my $pkg = Alien::Base::PkgConfig->new($_);
    $all{$pkg->{package}} = $pkg;
  };
  File::Find::find( $wanted, $self->dist_dir );
    
  croak "No Alien::Base::PkgConfig objects are stored!"
    unless keys %all;
  
  # Run through all pkgconfig objects and ensure that their modules are loaded:
  for my $pkg_obj (values %all) {
    my $perl_module_name = blessed $pkg_obj;
    eval "require $perl_module_name"; 
  }

  return @all{@_} if @_;

  my $manual = delete $all{_manual};

  if (keys %all) {
    return values %all;
  } else {
    return $manual;
  }
}

=head2 config

 my $value = Alien::MyLibrary->config($key);

Returns the configuration data as determined during the install
of L<Alien::MyLibrary>.  For the appropriate config keys, see 
L<Alien::Base::ModuleBuild::API#CONFIG-DATA>.

This is not typically used by L<Alien::Base> and L<alienfile>,
but a compatible interface will be provided.

=cut

# helper method to call Alien::MyLib::ConfigData->config(@_)
sub config {
  my $class = shift;
  $class = blessed $class || $class;

  if(my $ab_config = $class->runtime_prop)
  {
    my $key = shift;
    return $ab_config->{legacy}->{$key};
  }

  my $config = $class . '::ConfigData';
  eval "require $config";
  warn $@ if $@;

  return $config->config(@_);
}

# helper method to split flags based on the OS
sub split_flags {
  my ($class, $line) = @_;
  if( $^O eq 'MSWin32' ) {
    $class->split_flags_windows($line);
  } else {
    # $os eq 'Unix'
    $class->split_flags_unix($line);
  }
}

sub split_flags_unix {
  my ($class, $line) = @_;
  shellwords($line);
}

sub split_flags_windows {
  # NOTE a better approach would be to write a function that understands cmd.exe metacharacters.
  my ($class, $line) = @_;

  # Double the backslashes so that when they are unescaped by shellwords(),
  # they become a single backslash. This should be fine on Windows since
  # backslashes are not used to escape metacharacters in cmd.exe.
  $line =~ s,\\,\\\\,g;
  shellwords($line);
}

=head2 dynamic_libs

 my @dlls = Alien::MyLibrary->dynamic_libs;
 my($dll) = Alien::MyLibrary->dynamic_libs;

Returns a list of the dynamic library or shared object files for the
alien software.

=cut

sub dynamic_libs {
  my ($class) = @_;
  
  require FFI::CheckLib;
  
  if($class->install_type('system')) {

    my $name = $class->config('ffi_name');
    unless(defined $name) {