script to close stuck-open electrumx server connections

stale.php

<?php

echo "Starting.. ", date('Y-m-d H:i:s'), "\n";

$conns = [];

$lsof = `lsof -n -a -c electrumx -itcp -sTCP:ESTABLISHED -Ffn`;
$tok = strtok($lsof, "\n");

$pid = 0;
$fd = 0;

while ($tok !== false) {
	$op = substr($tok, 0, 1);
	$data = substr($tok, 1);
	switch ($op) {
		case 'p':
			$pid = $data;
			break;
		case 'f':
			$fd = $data;
			break;
		case 'n':
			$conns[$pid][$fd] = substr($data, strpos($data, '->') + 2);
			break;
	}
	$tok = strtok("\n");
}

$cmd = '/usr/local/bin/electrumx_rpc.py sessions | grep -o \'[^[:space:]]*$\' | grep -v Peer;';
$cmd .= '/usr/local/bin/electrumx_rpc.py peers | awk \'{if($2 == "good") {print $NF;}}\';';

$sessions = array_flip(explode("\n", shell_exec($cmd)));

foreach ($conns as $pid => &$fds) {
	foreach ($fds as $fd => $conn) {
		if (isset($sessions[$conn])) {
			unset($sessions[$conn]);
			unset($fds[$fd]);
		}
	}
}
unset($fds);

foreach ($conns as $pid => $fds) {
	$cmds = '';
	asort($fds);
	foreach ($fds as $fd => $conn) {
		echo "Closing pid $pid fd $fd to $conn\n";
		$cmds .= "call shutdown($fd, 2)\n";
	}
	if ($cmds != '') {
		$f = tempnam('/tmp', 'stale-electrum');
		if ($f === false) {
			break;
		}
		file_put_contents($f, $cmds);
		passthru(sprintf('gdb -p %d --batch -x %s', $pid, escapeshellarg($f)));
		unlink($f);
	}
}

echo "Finished.. ", date('Y-m-d H:i:s'), "\n";