package FFI::Raw::MemPtr;
$FFI::Raw::MemPtr::VERSION = '0.30';
use strict;
use warnings;
=head1 NAME
FFI::Raw::MemPtr - FFI::Raw memory pointer type
=head1 VERSION
version 0.30
=head1 DESCRIPTION
A B<FFI::Raw::MemPtr> represents a memory pointer which can be passed to
functions taking a C<FFI::Raw::ptr> argument.
The allocated memory is automatically deallocated once the object is not in use
anymore.
=head1 METHODS
=head2 new( $length )
Allocate a new C<FFI::Raw::MemPtr> of size C<$length> bytes.
=head2 new_from_buf( $buffer, $length )
Allocate a new C<FFI::Raw::MemPtr> of size C<$length> bytes and copy C<$buffer>
into it. This can be used, for example, to pass a pointer to a function that
takes a C struct pointer, by using C<pack()> or the L<Convert::Binary::C> module
to create the actual struct content.
For example, consider the following C code
struct some_struct {
int some_int;
char some_str[];
};
extern void take_one_struct(struct some_struct *arg) {
if (arg -> some_int == 42)
puts(arg -> some_str);
}
It can be called using FFI::Raw as follows:
use FFI::Raw;
my $packed = pack('ix![p]p', 42, 'hello');
my $arg = FFI::Raw::MemPtr -> new_from_buf($packed, length $packed);
my $take_one_struct = FFI::Raw -> new(
$shared, 'take_one_struct',
FFI::Raw::void, FFI::Raw::ptr
);
$take_one_struct -> ($arg);
Which would print C<hello>.
=head2 new_from_ptr( $ptr )
Allocate a new C<FFI::Raw::MemPtr> pointing to the C<$ptr>, which can be either
a C<FFI::Raw::MemPtr> or a pointer returned by another function.
This is the C<FFI::Raw> equivalent of a pointer to a pointer.
=head2 tostr( [$length] )
Convert a C<FFI::Raw::MemPtr> to a Perl string. If C<$length> is not provided,
the length of the string will be computed using C<strlen()>.
=head1 AUTHOR
Alessandro Ghedini <alexbio@cpan.org>
=head1 LICENSE AND COPYRIGHT
Copyright 2013 Alessandro Ghedini.
This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.
See http://dev.perl.org/licenses/ for more information.
=cut
1; # End of FFI::Raw::MemPtr