Subversion Repositories php_utils

<?php

/*

 * fixed_length_microtime() for PHP

 * Copyright 2022 Daniel Marschall, ViaThinkSoft

 * Version 2022-03-03

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

function fixed_length_microtime() {

        // This function outputs a fixed-length microtime (can be used for sorting)

        // Additionally, it ensures that the output is always different by waiting 1 microsecond

        $ary = explode('.', microtime(true));

        if (!isset($ary[1])) $ary[1] = 0;

        $ret = $ary[0].'_'.str_pad($ary[1], 4, 0, STR_PAD_RIGHT);

        while (true) {

                $ary = explode('.', microtime(true));

                if (!isset($ary[1])) $ary[1] = 0;

                $ret2 = $ary[0].'_'.str_pad($ary[1], 4, 0, STR_PAD_RIGHT);

                // Wait until the value changes. This ensures that the microtime will never be the same

                // sleep(0.1) does not work for some reason.

                if ($ret != $ret2) break;

        }

        return $ret;

}