<?php
class SharedArray implements ArrayAccess {
  private $db = NULL;

  public function __construct() {
    if ($this->db === NULL &&
        $this->db = sqlite_open('shared_array.db')) {
      @sqlite_query(
        $this->db,
        'CREATE TABLE shared_array
         (offset varchar(32) PRIMARY KEY,
          value  varchar(32));'
      );
    }
  }

  public function __destruct() {
    if ($this->db !== NULL) {
      sqlite_close($this->db);
    }

    $this->db = NULL;
  }

  public function offsetExists($offset) {
    $result = sqlite_query(
      $this->db,
      "SELECT offset
         FROM shared_array
        WHERE offset = '$offset';"
    );

    if ($result === FALSE) {
      return FALSE;
    } else {
      return TRUE;
    }
  }

  public function offsetGet($offset) {
    return sqlite_fetch_single(
      sqlite_query(
        $this->db,
        "SELECT value
           FROM shared_array
          WHERE offset = '$offset';"
      )
    );
  }

  public function offsetSet($offset, $value) {
    sqlite_query(
      $this->db,
      "REPLACE INTO shared_array
               (offset, value)
        VALUES ('$offset', '$value');"
    );
  }

  public function offsetUnset($offset) {
    sqlite_query(
      $this->db,
      "DELETE FROM shared_array
        WHERE offset = '$offset'"
    );
  }
}

$_SHARED = new SharedArray;
?>