preg_match has string size limit

问题

preg_match has limit of str on PHP 5.2.5

<?php
    $str1 = 'a@b%c@d' . str_repeat ('=', 33326);
    $str2 = 'a@b%c@d' . str_repeat ('=', 33327);
    $regexp = '/^(.*)@(.*)%(.*)$/si';

    echo preg_match ($regexp, $str1) ? "Correct " : "Wrong ";  // works correctly
    echo "\n";
    echo preg_match ($regexp, $str2) ? "Correct " : "Wrong ";  // exhibits the bug
    echo "\n";

回答1:

preg_last_error() after the second call returns 2 (=PREG_BACKTRACK_LIMIT_ERROR) so you might want to raise this value.

来源：https://stackoverflow.com/questions/6173223/preg-match-has-string-size-limit