[PHP-DEV] preg_replace w/evaluations eats memory From: chrism (chrism <email protected>)
Date: 08/17/00

I've not had much luck using the bug system with lynx, so i'll dump
this one here.

If someone could submit, thanks.

chrism <email protected>

<?php

/*
   This program demonstrates a memory problem with preg_replace and
   evaluations. The memory requirements of the script increase with
   each iteration.

   My original script was processing 2000 files, each with 10 preg
   operations - hence 20,000 iterations. It's memory usage skyrocketed
   to over 270mb.

   This was tested on a FreeBSD 3.3 system with php4-200007141145
 */

/* create a virtual source file */
$data = str_repeat("xzxzxzxzxzxzzxxz<TAG>memory</TAG>zxzxzxzxzxz", 10);

function replace_eval($string) {
                /* do nothing */
}

function replace() {
        global $data;

        $result = preg_replace("/(?x)
                                        (<\/?) # 1 opening tag
                                        (\w+) # 2 tag
                                        ([^>]*>) # 3 closing tag
                                        ([^<]*) # 4 body
                                /e",

                        "'replace_eval(\\4)'",

                        $data);
}

function loop() {
        for ($i = 0; $i < 20000; $i++) {
                replace();
        }
}

loop();

?> 

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