++ed by:
PABLROD ZMUGHAL

2 PAUSE users
2 non-PAUSE users.

Graham Ollis 🔥🐉
and 3 contributors

NAME

Alien::Base::Wrapper - Compiler and linker wrapper for Alien

VERSION

version 0.66

SYNOPSIS

From the command line:

 % perl -MAlien::Base::Wrapper=Alien::Foo,Alien::Bar -e cc -- -o foo.o -c foo.c
 % perl -MAlien::Base::Wrapper=Alien::Foo,Alien::Bar -e ld -- -o foo foo.o

From Makefile.PL (non-dynamic):

 use ExtUtils::MakeMaker;
 use Alien::Base::Wrapper qw( Alien::Foo Alien::Bar !export );
 
 WriteMakefile(
   'NAME'              => 'Foo::XS',
   'VERSION_FROM'      => 'lib/Foo/XS.pm',
   'CONFIGURE_REQUIRES => {
     'ExtUtils::MakeMaker' => 6.52,
     'Alien::Foo'          => 0,
     'Alien::Bar'          => 0,
   },
   Alien::Base::Wrapper->mm_args,
 );

From Makefile.PL (dynamic):

 use Devel::CheckLib qw( check_lib );
 use ExtUtils::MakeMaker 6.52;
 
 my @mm_args;
 my @libs;
 
 if(check_lib( lib => [ 'foo' ] )
 {
   push @mm_args, LIBS => [ '-lfoo' ];
 }
 else
 {
   push @mm_args,
     CC => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e cc --',
     LD => '$(FULLPERL) -MAlien::Base::Wrapper=Alien::Foo -e ld --',
     BUILD_REQUIRES => {
       'Alien::Foo'           => 0,
       'Alien::Base::Wrapper' => 0,
     }
   ;
 }

 WriteMakefile(
   'NAME'         => 'Foo::XS',
   'VERSION_FROM' => 'lib/Foo/XS.pm',
   'CONFIGURE_REQUIRES => {
     'ExtUtils::MakeMaker' => 6.52,
   },
   @mm_args,
 );

DESCRIPTION

This module acts as a wrapper around one or more Alien modules. It is designed to work with Alien::Base based aliens, but it should work with any Alien which uses the same essential API.

In the first example (from the command line), this class acts as a wrapper around the compiler and linker that Perl is configured to use. It takes the normal compiler and linker flags and adds the flags provided by the Aliens specified, and then executes the command. It will print the command to the console so that you can see exactly what is happening.

In the second example (from Makefile.PL non-dynamic), this class is used to generate the appropriate ExtUtils::MakeMaker (EUMM) arguments needed to WriteMakefile.

In the third example (from Makefile.PL dynamic), we do a quick check to see if the simple linker flag -lfoo will work, if so we use that. If not, we use a wrapper around the compiler and linker that will use the alien flags that are known at build time. The problem that this form attempts to solve is that compiler and linker flags typically need to be determined at configure time, when a distribution is installed, meaning if you are going to use an Alien module then it needs to be a configure prerequisite, even if the library is already installed and easily detected on the operating system.

The author of this module believes that the third (from Makefile.PL dynamic) form is somewhat unnecessary. Alien modules based on Alien::Base have a few prerequisites, but they are well maintained and reliable, so while there is a small cost in terms of extra dependencies, the overall reliability thanks to reduced overall complexity.

FUNCTIONS

cc

 % perl -MAlien::Base::Wrapper=Alien::Foo -e cc -- cflags

Invoke the C compiler with the appropriate flags from Alien::Foo and what is provided on the command line.

ld

 % perl -MAlien::Base::Wrapper=Alien::Foo -e ld -- ldflags

Invoke the linker with the appropriate flags from Alien::Foo and what is provided on the command line.

mm_args

 my %args = Alien::Base::Wrapper->mm_args;

Returns arguments that you can pass into WriteMakefile to compile/link against the specified Aliens.

mb_args

 my %args = Alien::Base::Wrapper->mb_args;

Returns arguments that you can pass into the constructor to Module::Build.

ENVIRONMENT

Alien::Base::Wrapper responds to these environment variables:

ALIEN_BASE_WRAPPER_QUIET

If set to true, do not print the command before executing

SEE ALSO

Alien::Base, Alien::Base

AUTHOR

Author: Graham Ollis <plicease@cpan.org>

Contributors:

Diab Jerius (DJERIUS)

Roy Storey

Ilya Pavlov

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Graham Ollis.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.