#!/usr/bin/env perl

# WWW interface for amplifier, ipa_control_server.pl

## Start user config
#
# port to bind to
$port = 2600;
# file to log connections, writable by whatever uid this is running as
$log = "/var/log/ipa_control_server.log";
# path to ipa_control
$ipac = "/usr/local/bin/ipa_control";
# null all messages
$null = ">/dev/null 2>&1";
#
# End user config

use Socket;
use FileHandle;

sub spawn;

sub Do_It_Disco_Fluid {

print LOG "($_)\n";

if ((0xffff & system $args) != 0) {
        print "error: $!\n";
	exit 1;
}

exit 0;

}

$proto = getprotobyname('tcp');

socket(Server, PF_INET, SOCK_STREAM, $proto) or die "socket: $!\n";
setsockopt(Server, SOL_SOCKET, SO_REUSEADDR, pack("l", 1)) or die "setsockopt: $!\n";  
bind(Server, sockaddr_in ($port, INADDR_ANY)) or die "bind: $!\n";
listen(Server, SOMAXCONN) or die "listen $!\n";

$paddr = 0; $iaddr = 0; $name = 0; $_ = 0; @_ = (0); $coderef = 0; $pid = 0; 
$waitedpid = 0; $port=0;

sub ABDUCTOR {
$waitedpid = wait;
$SIG{CHLD} = \&ABDUCTOR;
}

$SIG{CHLD} = \&ABDUCTOR;

for (; $paddr = accept(Client, Server); close Client) {

($port, $iaddr) = sockaddr_in($paddr);

$name = gethostbyaddr($iaddr, AF_INET);

spawn sub {

    open LOG,">>$log" or warn "Can't open $log: $!\n";
        print LOG "\n", scalar gmtime, "\n".
                  "Connection from $name [", inet_ntoa($iaddr);
        print LOG "] at port $port ";


    while ($_ = <STDIN>) {

    	s/[\r\n]//g;
    	tr/a-zA-Z //csd;

    	if ($_ eq "HIGH") {
		&Do_It_Disco_Fluid($args = "$ipac -B $null");
    	}

    	elsif ($_ eq "MIDDLE HIGH") {
		&Do_It_Disco_Fluid($args = "$ipac -b $null");
    	}

    	elsif ($_ eq "MIDDLE") {
		&Do_It_Disco_Fluid($args = "$ipac -m $null");
    	}

    	elsif ($_ eq "MIDDLE LOW") {
		&Do_It_Disco_Fluid($args = "$ipac -l $null");
    	}

    	elsif ($_ eq "LOW") {
		&Do_It_Disco_Fluid($args = "$ipac -L $null");
    	}
    
    	else {
		print LOG "(unknown: $_)\n";
		exit 1;
    	}
  }
 };
}

sub spawn {

local ($coderef, $pid);

$coderef = shift;
@_ = ();
$_ = "";

if (!defined ($pid = fork)) {
	return;
}

elsif ($pid) {
	return;
}

open STDIN, "<&Client" or die "Can't dup client to stdin\n";
open STDOUT, ">&Client" or die "Can't dup client to stdout\n";
STDOUT->autoflush();
exit &$coderef();
}