source: vendor/paragonie/random_compat/other/build_phar.php

<?php
$dist = dirname(__DIR__).'/dist';
if (!is_dir($dist)) {
    mkdir($dist, 0755);
}
if (file_exists($dist.'/random_compat.phar')) {
    unlink($dist.'/random_compat.phar');
}
$phar = new Phar(
    $dist.'/random_compat.phar',
    FilesystemIterator::CURRENT_AS_FILEINFO | \FilesystemIterator::KEY_AS_FILENAME,
    'random_compat.phar'
);
rename(
    dirname(__DIR__).'/lib/random.php', 
    dirname(__DIR__).'/lib/index.php'
);
$phar->buildFromDirectory(dirname(__DIR__).'/lib');
rename(
    dirname(__DIR__).'/lib/index.php', 
    dirname(__DIR__).'/lib/random.php'
);

/**
 * If we pass an (optional) path to a private key as a second argument, we will
 * sign the Phar with OpenSSL.
 * 
 * If you leave this out, it will produce an unsigned .phar!
 */
if ($argc > 1) {
    if (!@is_readable($argv[1])) {
        echo 'Could not read the private key file:', $argv[1], "\n";
        exit(255);
    }
    $pkeyFile = file_get_contents($argv[1]);
    
    $private = openssl_get_privatekey($pkeyFile);
    if ($private !== false) {
        $pkey = '';
        openssl_pkey_export($private, $pkey);
        $phar->setSignatureAlgorithm(Phar::OPENSSL, $pkey);
        
        /**
         * Save the corresponding public key to the file
         */
        if (!@is_readable($dist.'/random_compat.phar.pubkey')) {
            $details = openssl_pkey_get_details($private);
            file_put_contents(
                $dist.'/random_compat.phar.pubkey',
                $details['key']
            );
        }
    } else {
        echo 'An error occurred reading the private key from OpenSSL.', "\n";
        exit(255);
    }
}