NAME

    FFI::CheckLib - Check that a library is available for FFI

VERSION

    version 0.04

SYNOPSIS

      use FFI::CheckLib;
      
      check_lib_or_exit( lib => 'jpeg', symbol => 'jinit_memory_mgr' );
      check_lib_or_exit( lib => [ 'iconv', 'jpeg' ] );
      
      # or prompt for path to library and then:
      print "where to find jpeg library: ";
      my $path = <STDIN>;
      check_lib_or_exit( lib => 'jpeg', libpath => $path );

DESCRIPTION

    This module checks whether a particular dynamic library is available
    for FFI to use. It is modeled heavily on Devel::CheckLib, but will find
    dynamic libraries even when development packages are not installed. It
    also provides a find_lib function that will return the full path to the
    found dynamic library, which can be feed directly into FFI::Raw.

    Although intended mainly for FFI modules via FFI::Raw and similar, this
    module does not actually use any FFI to do its detection and probing.
    This module does not have any non-core dependencies other than
    Module::Build on Perl 5.20 and more recent.

FUNCTIONS

    All of these take the same named parameters and are exported by
    default.

 find_lib

    This will return a list of dynamic libraries, or empty list if none
    were found.

  lib

    Must be either a string with the name of a single library or a
    reference to an array of strings of library names. Depending on your
    platform, CheckLib will prepend lib or append .dll or .so when
    searching.

  libpath

    A string or array of additional paths to search for libraries.

  symbol

    A string or a list of symbol names that must be found.

  verify

    A code reference used to verify a library really is the one that you
    want. It should take two arguments, which is the name of the library
    and the full path to the library pathname. It should return true if it
    is acceptable, and false otherwise. You can use this in conjunction
    with FFI::Raw to determine if it is going to meet your needs. Example:

     use FFI::CheckLib;
     use FFI::Raw;
     
     my($lib) = find_lib(
       name => 'foo',
       verify => sub {
         my($name, $libpath) = @_;
         
         my $new = FFI::Raw->new(
           $lib, 'foo_new',
           FFI::Raw::ptr,
         );
         
         my $delete = FFI::Raw->new(
           $lib, 'foo_delete',
           FFI::Raw::void,
           FFI::Raw::ptr,
         );
         
         # return true if new returns
         # a pointer, not forgetting
         # to free it on success.
         my $ptr = $new->call();
         return 0 unless $ptr;
         $delete->call();
         return 1;
       },
     );

 assert_lib

    This behaves exactly the same as find_lib, except that instead of
    returning empty list of failure it throws an exception.

 check_lib_or_exit

    This behaves exactly the same as assert_lib, except that instead of
    dying, it warns (with exactly the same error message) and exists. This
    is intended for use in Makefile.PL or Build.PL

 check_lib

    This behaves exactly the same as find_lib, except that it returns true
    (1) on finding the appropriate libraries or false (0) otherwise.

AUTHOR

    Graham Ollis <plicease@cpan.org>

COPYRIGHT AND LICENSE

    This software is copyright (c) 2014 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.

