<?php
class HandleMemorySegments {

    public function createMemory($size = 100) {
        $strReturn = '';
        while (true) {
            $strMemID = "0x" . $this->generateMemoryID();
            $strReturn = shmop_open($strMemID, "n", 0777, $size);
            if ($strReturn != false) {
                break;
            }
        }
        return $strReturn;
    }
    public function readMemory($id ,$amount ,$offsetStart = 0) {
        return shmop_read ($id, $offsetStart, $amount);
    }
    public function writeMemory($id, $data, $offset = 0) {
        $id = intval($id);
        $semid=sem_get($id,1,0777);
        sem_acquire($semid);
        shmop_write($id, $data, $offset);
        sem_release($semid);
    }
    public function deleteMemory($id) {
        shmop_delete($id);
    }
    public function generateMemoryID() {
        $x = '';
        $hex='';
        for ($i = 0; $i<3; $i++)
        {
            $x .=  dechex(rand(0,15));
        }

        for ($i=0; $i < strlen($x); $i++)
        {
            $hex .= dechex(ord($x[$i]));
        }

        return $hex;
    }

    public function _count($shmopId){
        $size = (int) shmop_size($shmopId);

        $dataInSH = shmop_read($shmopId, 0, $size);
        $dataSizeInSH = 0;

        for ($i = 0; $i < $size; $i++) {
            if ($this->strToHex($dataInSH[$i]) != 0) {
                $dataSizeInSH++;
            }
        }

        return $dataSizeInSH;
    }

    protected function strToHex($string) {
        $hex='';
        for ($i=0; $i < strlen($string); $i++)
        {
            $hex .= dechex(ord($string[$i]));
        }
        return $hex;
    }

}