#!perl
use strict;
use warnings;

use ExtUtils::MakeMaker;
use ExtUtils::Constant 0.23 'WriteConstants';
use Config;

my @DEFINES;

my $cb;
my $seq = 0;
sub check_for
{
    my %args = @_;
    return if exists $Config{$args{confkey}};

    require ExtUtils::CBuilder;
    $cb ||= ExtUtils::CBuilder->new( quiet => 1 );

    my $main = $args{main};

    print "Checking $args{define}...\n";

    my $file_base = "test-$seq"; $seq++;

    my $file_source = "$file_base.c";

    {
	open( my $file_source_fh, ">", $file_source ) or die "Cannot write $file_source - $!";
	print $file_source_fh <<"EOF";
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
int main(int argc, char *argv[])
  {
    (void)argc;
    (void)argv;
    $main
    return 0;
  }
EOF
    }

    my $file_obj = eval { $cb->compile( source => $file_source ) };
    unlink $file_source;

    return 0 unless defined $file_obj;

    my $file_exe = eval { $cb->link_executable( objects => $file_obj ) };
    unlink $file_obj;

    return 0 unless defined $file_exe;

    # Don't need to try running it
    unlink $file_exe;

    push @DEFINES, $args{define};
}

sub check_for_func
{
    my %args = @_;
    my $func = delete $args{func};
    check_for( %args, main => "void *p = &$func; (void)p;" );
}

my %defines = (
    # -Dfoo               func()        $Config{key}
    HAS_GETADDRINFO => [ "getaddrinfo", "d_getaddrinfo" ],
    HAS_GETNAMEINFO => [ "getnameinfo", "d_getnameinfo" ],
    HAS_INET_ATON   => [ "inet_aton",   "d_inetaton" ],
    HAS_INETNTOP    => [ "inet_ntop",   "d_inetntop" ],
    HAS_INETPTON    => [ "inet_pton",   "d_inetpton" ],
);

foreach my $define ( sort keys %defines ) {
    my ( $func, $key ) = @{$defines{$define}};
    check_for_func( 
	confkey => $key,
	define  => $define,
	func    => $func
    );
}

check_for(
    confkey => "d_sockaddr_sa_len",
    define  => "HAS_SOCKADDR_SA_LEN",
    main    => "struct sockaddr sa; sa.sa_len = 0;"
);

check_for(
    confkey => "d_sockaddr_in6",
    define  => "HAS_SOCKADDR_IN6",
    main    => "struct sockaddr_in6 sin6; sin6.sin6_family = AF_INET6;"
);

check_for(
    confkey => "d_sin6_scope_id",
    define  => "HAS_SIN6_SCOPE_ID",
    main    => "struct sockaddr_in6 sin6; sin6.sin6_scope_id = 0;"
);

check_for(
    confkey => "d_ipv6_mreq",
    define  => "HAS_IPV6_MREQ",
    main    => "struct ipv6_mreq mreq; mreq.ipv6mr_interface = 0;"
);

my %makefile_args;

# Since we're providing a later version of a core module, before 5.12 the
# @INC order is wrong so we'll have to go in perl rather than site dirs
$makefile_args{INSTALLDIRS} = "perl" if $] < 5.012;

WriteMakefile(
    NAME	  => 'Socket',
    VERSION_FROM  => 'Socket.pm',
    # ABSTRACT_FROM gets confused by C<Socket>
    ABSTRACT      => 'networking constants and support functions',
   ($Config{libs} =~ /(-lsocks\S*)/ ? (LIBS => [ "$1" ] ) : ()),
    XSPROTOARG    => '-noprototypes', 		# XXX remove later?
    realclean     => {FILES=> 'const-c.inc const-xs.inc'},
    DEFINE        => join( " ", map { "-D$_" } @DEFINES ),
    CONFIGURE_REQUIRES => {
	'ExtUtils::CBuilder' => 0,
	'ExtUtils::Constant' => '0.23',
    },
    MIN_PERL_VERSION => '5.006001',
    LICENSE       => 'perl',
    %makefile_args,
);
my @names = (
    qw(
	AF_802 AF_AAL AF_APPLETALK AF_CCITT AF_CHAOS AF_CTF AF_DATAKIT
	AF_DECnet AF_DLI AF_ECMA AF_GOSIP AF_HYLINK AF_IMPLINK AF_INET AF_INET6
	AF_ISO AF_KEY AF_LAST AF_LAT AF_LINK AF_MAX AF_NBS AF_NIT AF_NS AF_OSI
	AF_OSINET AF_PUP AF_ROUTE AF_SNA AF_UNIX AF_UNSPEC AF_USER AF_WAN
	AF_X25

	AI_ADDRCONFIG AI_ALL AI_CANONIDN AI_CANONNAME AI_IDN
	AI_IDN_ALLOW_UNASSIGNED AI_IDN_USE_STD3_ASCII_RULES AI_NUMERICHOST
	AI_NUMERICSERV AI_PASSIVE AI_V4MAPPED

	EAI_ADDRFAMILY EAI_AGAIN EAI_BADFLAGS EAI_BADHINTS EAI_FAIL EAI_FAMILY
	EAI_NODATA EAI_NONAME EAI_PROTOCOL EAI_SERVICE EAI_SOCKTYPE EAI_SYSTEM

	IOV_MAX

	IP_OPTIONS IP_HDRINCL IP_TOS IP_TTL IP_RECVOPTS IP_RECVRETOPTS
	IP_RETOPTS

	IPV6_ADD_MEMBERSHIP IPV6_DROP_MEMBERSHIP IPV6_MTU IPV6_MTU_DISCOVER
	IPV6_MULTICAST_HOPS IPV6_MULTICAST_IF IPV6_MULTICAST_LOOP
	IPV6_UNICAST_HOPS IPV6_V6ONLY

	MSG_BCAST MSG_BTAG MSG_CTLFLAGS MSG_CTLIGNORE MSG_DONTWAIT MSG_EOF
	MSG_EOR MSG_ERRQUEUE MSG_ETAG MSG_FIN MSG_MAXIOVLEN MSG_MCAST
	MSG_NOSIGNAL MSG_RST MSG_SYN MSG_TRUNC MSG_URG MSG_WAITALL MSG_WIRE

	NI_DGRAM NI_IDN NI_IDN_ALLOW_UNASSIGNED NI_IDN_USE_STD3_ASCII_RULES
	NI_NAMEREQD NI_NOFQDN NI_NUMERICHOST NI_NUMERICSERV

	PF_802 PF_AAL PF_APPLETALK PF_CCITT PF_CHAOS PF_CTF PF_DATAKIT
	PF_DECnet PF_DLI PF_ECMA PF_GOSIP PF_HYLINK PF_IMPLINK PF_INET PF_INET6
	PF_ISO PF_KEY PF_LAST PF_LAT PF_LINK PF_MAX PF_NBS PF_NIT PF_NS PF_OSI
	PF_OSINET PF_PUP PF_ROUTE PF_SNA PF_UNIX PF_UNSPEC PF_USER PF_WAN
	PF_X25

	SCM_CONNECT SCM_CREDENTIALS SCM_CREDS SCM_TIMESTAMP

	SOCK_DGRAM SOCK_RAW SOCK_RDM SOCK_SEQPACKET SOCK_STREAM

	SOL_SOCKET 

	SOMAXCONN

	SO_ACCEPTCONN SO_ATTACH_FILTER SO_BACKLOG SO_BROADCAST SO_CHAMELEON
	SO_DEBUG SO_DETACH_FILTER SO_DGRAM_ERRIND SO_DOMAIN SO_DONTLINGER
	SO_DONTROUTE SO_ERROR SO_FAMILY SO_KEEPALIVE SO_LINGER SO_OOBINLINE
	SO_PASSCRED SO_PASSIFNAME SO_PEERCRED SO_PROTOCOL SO_PROTOTYPE
	SO_RCVBUF SO_RCVLOWAT SO_RCVTIMEO SO_REUSEADDR SO_REUSEPORT
	SO_SECURITY_AUTHENTICATION SO_SECURITY_ENCRYPTION_NETWORK
	SO_SECURITY_ENCRYPTION_TRANSPORT SO_SNDBUF SO_SNDLOWAT SO_SNDTIMEO
	SO_STATE SO_TYPE SO_USELOOPBACK SO_XOPEN SO_XSE

	TCP_KEEPALIVE TCP_MAXRT TCP_MAXSEG TCP_NODELAY TCP_STDURG TCP_CORK
	TCP_KEEPIDLE TCP_KEEPINTVL TCP_KEEPCNT TCP_SYNCNT TCP_LINGER2
	TCP_DEFER_ACCEPT TCP_WINDOW_CLAMP TCP_INFO TCP_QUICKACK TCP_CONGESTION
	TCP_MD5SIG

	UIO_MAXIOV
    ),
    {name=>"IPPROTO_IP",   type=>"IV", default=>["IV",   0]},
    {name=>"IPPROTO_IPV6", type=>"IV", default=>["IV",  41]},
    {name=>"IPPROTO_RAW",  type=>"IV", default=>["IV", 255]},
    {name=>"IPPROTO_ICMP", type=>"IV", default=>["IV",  1]},
    {name=>"IPPROTO_TCP",  type=>"IV", default=>["IV",  6]},
    {name=>"IPPROTO_UDP",  type=>"IV", default=>["IV", 17]},
    {name=>"SHUT_RD",   type=>"IV", default=>["IV", "0"]},
    {name=>"SHUT_WR",   type=>"IV", default=>["IV", "1"]},
    {name=>"SHUT_RDWR", type=>"IV", default=>["IV", "2"]},
);

push @names, {
    name  => $_,
    type  => "IV",
    macro => [ "#if defined($_) || defined(HAS_$_) /* might be an enum */\n",
               "#endif\n" ]
} foreach qw (MSG_CTRUNC MSG_DONTROUTE MSG_OOB MSG_PEEK MSG_PROXY SCM_RIGHTS);

push @names, {
    name  => $_,
    type  => "SV",
    pre   => "struct in_addr ip_address; ip_address.s_addr = htonl($_);",
    value => "newSVpvn_flags((char *)&ip_address,sizeof(ip_address), SVs_TEMP)",
} foreach qw(INADDR_ANY INADDR_LOOPBACK INADDR_NONE INADDR_BROADCAST);

push @names, {
    name  => $_,
    type  => "SV",
    macro => [ "#ifdef ${_}_INIT\n",
               "#endif\n" ],
    pre   => "struct in6_addr ip6_address = ${_}_INIT;",
    value => "newSVpvn_flags((char *)&ip6_address,sizeof(ip6_address), SVs_TEMP)",
} foreach qw(IN6ADDR_ANY IN6ADDR_LOOPBACK);

# Work around an old Perl core bug that affects ExtUtils::Constants on
# pre-5.8.2 Perls.  EU:C should be amended to work around this itself.
if("$]" < 5.008002) {
    require ExtUtils::Constant::ProxySubs;
    no warnings "once";
    $ExtUtils::Constant::ProxySubs::type_to_C_value{$_} = sub { () }
        foreach qw(YES NO UNDEF), "";
}

WriteConstants(
    PROXYSUBS => {autoload => 1},
    NAME => 'Socket',
    NAMES => \@names,
);