package Net::HTTP::NB;

$Net::HTTP::NB::VERSION = '6.17';

use strict;

use warnings;

use base 'Net::HTTP';

sub can_read {

    return 1;

}

sub sysread {

    my $self = $_[0];

    if (${*$self}{'httpnb_read_count'}++) {

	${*$self}{'http_buf'} = ${*$self}{'httpnb_save'};

	die "Multi-read\n";

    }

    my $buf;

    my $offset = $_[3] || 0;

    my $n = sysread($self, $_[1], $_[2], $offset);

    ${*$self}{'httpnb_save'} .= substr($_[1], $offset);

    return $n;

}

sub read_response_headers {

    my $self = shift;

    ${*$self}{'httpnb_read_count'} = 0;

    ${*$self}{'httpnb_save'} = ${*$self}{'http_buf'};

    my @h = eval { $self->SUPER::read_response_headers(@_) };

    if ($@) {

	return if $@ eq "Multi-read\n";

	die;

    }

    return @h;

}

sub read_entity_body {

    my $self = shift;

    ${*$self}{'httpnb_read_count'} = 0;

    ${*$self}{'httpnb_save'} = ${*$self}{'http_buf'};

    # XXX I'm not so sure this does the correct thing in case of

    # transfer-encoding transforms

    my $n = eval { $self->SUPER::read_entity_body(@_); };

    if ($@) {

	$_[0] = "";

	return -1;

    }

    return $n;

}

1;

=pod

=encoding UTF-8

=head1 NAME

Net::HTTP::NB - Non-blocking HTTP client

=head1 VERSION

version 6.17

=head1 SYNOPSIS

 use Net::HTTP::NB;

 my $s = Net::HTTP::NB->new(Host => "www.perl.com") || die $@;

 $s->write_request(GET => "/");

 use IO::Select;

 my $sel = IO::Select->new($s);

 READ_HEADER: {

    die "Header timeout" unless $sel->can_read(10);

    my($code, $mess, %h) = $s->read_response_headers;

    redo READ_HEADER unless $code;

 }

 while (1) {

    die "Body timeout" unless $sel->can_read(10);

    my $buf;

    my $n = $s->read_entity_body($buf, 1024);

    last unless $n;

    print $buf;

 }

=head1 DESCRIPTION

Same interface as C<Net::HTTP> but it will never try multiple reads

when the read_response_headers() or read_entity_body() methods are

invoked.  This make it possible to multiplex multiple Net::HTTP::NB

using select without risk blocking.

If read_response_headers() did not see enough data to complete the

headers an empty list is returned.

If read_entity_body() did not see new entity data in its read

the value -1 is returned.

=head1 SEE ALSO

L<Net::HTTP>

=head1 AUTHOR

Gisle Aas <gisle@activestate.com>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2001-2017 by Gisle Aas.

This is free software; you can redistribute it and/or modify it under

the same terms as the Perl 5 programming language system itself.

=cut

__END__

#ABSTRACT: Non-blocking HTTP client