dimaslanjaka / universal-framework

src/shim/mysql.php

<?php

/**
 * php7-mysql-shim
 *
 * @author Davey Shafik <me@daveyshafik.com>
 * @copyright Copyright (c) 2017 Davey Shafik
 * @license MIT License
 * @link https://github.com/dshafik/php7-mysql-shim
 */

/**
 * A drop-in replacement for ext/mysql in PHP 7+ using ext/mysqli instead
 *
 * This library is meant to be a _stop-gap_. It will be slower than using
 * the native functions directly.
 *
 * You should switch to ext/pdo_mysql or ext/mysqli, and migrate to prepared
 * queries (@see http://php.net/manual/en/pdo.prepared-statements.php) to
 * ensure you are securely interacting with your database.
 */

namespace {

  if (!extension_loaded('mysql')) {
    if (!extension_loaded('mysqli')) {
      trigger_error('php7-mysql-shim: ext/mysqli is required', E_USER_ERROR);
    }

    define('MYSQL_ASSOC', 1);
    define('MYSQL_NUM', 2);
    define('MYSQL_BOTH', 3);
    define('MYSQL_CLIENT_COMPRESS', 32);
    define('MYSQL_CLIENT_SSL', 2048);
    define('MYSQL_CLIENT_INTERACTIVE', 1024);
    define('MYSQL_CLIENT_IGNORE_SPACE', 256);

    function mysql_connect(
      $hostname = null,
      $username = null,
      $password = null,
      $new = false,
      $flags = 0
    ) {
      if (null === $hostname) {
        $hostname = ini_get('mysqli.default_host') ?: null;
      }
      if (null === $username) {
        $username = ini_get('mysqli.default_user') ?: null;
      }
      if (null === $password) {
        $password = ini_get('mysqli.default_pw') ?: null;
      }

      $hash = sha1($hostname . $username . $flags);
      /* persistent connections start with p: */
      /* don't use a cached link for those */
      if (!$new && $hostname[1] !== ':' && isset(\UniversalFramework\MySQL::$connections[$hash])) {
        \UniversalFramework\MySQL::$last_connection = \UniversalFramework\MySQL::$connections[$hash]['conn'];
        \UniversalFramework\MySQL::$connections[$hash]['refcount'] += 1;
        return \UniversalFramework\MySQL::$connections[$hash]['conn'];
      }

      /* A custom port can be specified by appending the hostname with :{port} e.g. hostname:3307 */
      if (preg_match('/^(.+):([\d]+)$/', $hostname, $port_matches) === 1 && $port_matches[1] !== "p") {
        $hostname = $port_matches[1];
        $port = (int) $port_matches[2];
      } else {
        $port = null;
      }

      /* No flags, means we can use mysqli_connect() */
      if ($flags === 0) {
        $conn = mysqli_connect($hostname, $username, $password, '', $port);

The call to mysqli_connect() has too few arguments starting with socket.

        if (!$conn instanceof mysqli) {
          return false;
        }
        \UniversalFramework\MySQL::$last_connection = $conn;
        $conn->hash = $hash;

The property hash does not seem to exist on mysqli.

        \UniversalFramework\MySQL::$connections[$hash] = array('refcount' => 1, 'conn' => $conn);

        return $conn;
      }

      /* Flags means we need to use mysqli_real_connect() instead, and handle exceptions */
      try {
        \UniversalFramework\MySQL::$last_connection = $conn = mysqli_init();

        mysqli_real_connect(
          $conn,
          $hostname,
          $username,
          $password,
          '',
          $port,
          '',
          $flags
        );

        // @codeCoverageIgnoreStart
        // PHPUnit turns the warning from mysqli_real_connect into an exception, so this never runs
        if ($conn === false) {
          return false;
        }
        // @codeCoverageIgnoreEnd

        $conn->hash = $hash;
        \UniversalFramework\MySQL::$connections[$hash] = array('refcount' => 1, 'conn' => $conn);

        return $conn;
      } catch (\Throwable $e) {
        trigger_error($e->getMessage(), E_USER_WARNING);
        // @codeCoverageIgnoreStart
        // PHPUnit turns the warning into an exception, so this never runs
        return false;
        // @codeCoverageIgnoreEnd
      }
    }

    function mysql_pconnect(
      $hostname = null,
      $username = null,
      $password = null,
      $flags = 0
    ) {
      $hostname = 'p:' . $hostname;
      return mysql_connect($hostname, $username, $password, false, $flags);
    }

    function mysql_close(\mysqli $link = null)
    {
      $isDefault = ($link === null);

      $link = \UniversalFramework\MySQL::getConnection($link, __FUNCTION__);

__FUNCTION__ of type string is incompatible with the type UniversalFramework\function expected by parameter $func of UniversalFramework\MySQL::getConnection().

      if ($link === null) {
        // @codeCoverageIgnoreStart
        // PHPUnit Warning -> Exception
        return false;
        // @codeCoverageIgnoreEnd
      }

      if (isset(\UniversalFramework\MySQL::$connections[$link->hash])) {

The property hash does not seem to exist on mysqli.

        \UniversalFramework\MySQL::$connections[$link->hash]['refcount'] -= 1;
      }

      $return = true;
      if (\UniversalFramework\MySQL::$connections[$link->hash]['refcount'] === 0) {
        $return = mysqli_close($link);

It seems like $link can also be of type false; however, parameter $mysql of mysqli_close() does only seem to accept mysqli, maybe add an additional type check?

        unset(\UniversalFramework\MySQL::$connections[$link->hash]);
      }

      if ($isDefault) {
        UniversalFramework\MySQL::$last_connection = null;
      }

      return $return;
    }

    function mysql_select_db($databaseName, \mysqli $link = null)
    {
      $link = \UniversalFramework\MySQL::getConnection($link);

      return mysqli_query(
        $link,

It seems like $link can also be of type false; however, parameter $mysql of mysqli_query() does only seem to accept mysqli, maybe add an additional type check?

        'USE `' . mysqli_real_escape_string($link, $databaseName) . '`'

It seems like $link can also be of type false; however, parameter $mysql of mysqli_real_escape_string() does only seem to accept mysqli, maybe add an additional type check?

      ) !== false;
    }

    function mysql_query($query, \mysqli $link = null)
    {
      return mysqli_query(\UniversalFramework\MySQL::getConnection($link), $query);

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_query() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_unbuffered_query($query, \mysqli $link = null)
    {
      $link = \UniversalFramework\MySQL::getConnection($link);
      if (mysqli_real_query($link, $query)) {

It seems like $link can also be of type false; however, parameter $mysql of mysqli_real_query() does only seem to accept mysqli, maybe add an additional type check?

        return mysqli_use_result($link);

It seems like $link can also be of type false; however, parameter $mysql of mysqli_use_result() does only seem to accept mysqli, maybe add an additional type check?

      }

      return false;
    }

    function mysql_db_query($databaseName, $query, \mysqli $link = null)
    {
      if (mysql_select_db($databaseName, $link)) {

It seems like $link can also be of type mysqli; however, parameter $link_identifier of mysql_select_db() does only seem to accept resource, maybe add an additional type check?

        return mysql_query($query, $link);

It seems like $link can also be of type mysqli; however, parameter $link_identifier of mysql_query() does only seem to accept resource, maybe add an additional type check?

      }
      return false;
    }

    function mysql_list_dbs(\mysqli $link = null)
    {
      return mysql_query('SHOW DATABASES', $link);

It seems like $link can also be of type mysqli; however, parameter $link_identifier of mysql_query() does only seem to accept resource, maybe add an additional type check?

    }

    function mysql_list_tables($databaseName, \mysqli $link = null)
    {
      $link = \UniversalFramework\MySQL::getConnection($link);
      $query = sprintf(
        'SHOW TABLES FROM `%s`',
        mysql_real_escape_string($databaseName, $link)

$link of type false|mysqli is incompatible with the type resource expected by parameter $link_identifier of mysql_real_escape_string().

      );
      return mysql_query($query, $link);

$link of type false|mysqli is incompatible with the type resource expected by parameter $link_identifier of mysql_query().

    }

    function mysql_list_fields($databaseName, $tableName, \mysqli $link = null)
    {
      $link = \UniversalFramework\MySQL::getConnection($link);

      $query = sprintf(
        'SHOW COLUMNS FROM `%s`.`%s`',
        mysqli_real_escape_string($link, $databaseName),

It seems like $link can also be of type false; however, parameter $mysql of mysqli_real_escape_string() does only seem to accept mysqli, maybe add an additional type check?

        mysqli_real_escape_string($link, $tableName)
      );

      $result = mysql_query($query, $link);

$link of type false|mysqli is incompatible with the type resource expected by parameter $link_identifier of mysql_query().

      if ($result instanceof \mysqli_result) {

$result is never a sub-type of mysqli_result.

        $result->table = $tableName;
        return $result;
      }

      trigger_error('mysql_list_fields(): Unable to save MySQL query result', E_USER_WARNING);
      // @codeCoverageIgnoreStart
      return false;
      // @codeCoverageIgnoreEnd
    }

    function mysql_list_processes(\mysqli $link = null)
    {
      return mysql_query('SHOW PROCESSLIST', $link);

It seems like $link can also be of type mysqli; however, parameter $link_identifier of mysql_query() does only seem to accept resource, maybe add an additional type check?

    }

    function mysql_error(\mysqli $link = null)
    {
      return mysqli_error(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_error() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_errno(\mysqli $link = null)
    {
      return mysqli_errno(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_errno() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_affected_rows(\mysqli $link = null)
    {
      return mysqli_affected_rows(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_affected_rows() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_insert_id($link = null) /*|*/
    {
      return mysqli_insert_id(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_insert_id() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_result($result, $row, $field = 0)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      if (!mysqli_data_seek($result, $row)) {
        trigger_error(
          sprintf(
            'mysql_result(): Unable to jump to row %d on MySQL result index %s',
            $row,
            spl_object_hash($result)
          ),
          E_USER_WARNING
        );
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      $found = true;
      if (strpos($field, '.') !== false) {
        list($table, $name) = explode('.', $field);
        $i = 0;
        $found = false;
        mysqli_field_seek($result, 0);
        while ($column = mysqli_fetch_field($result)) {
          if ($column->table === $table && $column->name === $name) {
            $field = $i;
            $found = true;
            break;
          }
          $i++;
        }
      }

      $row = mysql_fetch_array($result);
      if ($found && array_key_exists($field, $row)) {
        return $row[$field];
      }

      trigger_error(
        sprintf(
          '%s(): %s not found in MySQL result index %s',
          __FUNCTION__,
          $field,
          spl_object_hash($result)
        ),
        E_USER_WARNING
      );
      // @codeCoverageIgnoreStart
      return false;
      // @codeCoverageIgnoreEnd
    }

    function mysql_num_rows($result)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      $previous = error_reporting(0);
      $rows = mysqli_num_rows($result);
      error_reporting($previous);

      return $rows;
    }

    function mysql_num_fields($result)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_num_fields($result);
    }

    function mysql_fetch_row($result)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_fetch_row($result) ?: false;
    }
    /**
     * Fetch result as assoc array
     *
     * @param [type] $result

The doc comment [type] at position 0 could not be parsed: Unknown type name '[' at position 0 in [type].

     * @param [type] $resultType
     * @return array|null
     */
    function mysql_fetch_array($result, $resultType = MYSQL_BOTH)

The constant MYSQL_BOTH has been deprecated: 5.5

    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;

The expression return false returns the type false which is incompatible with the documented return type array|null.

        // @codeCoverageIgnoreEnd
      }
      return mysqli_fetch_array($result, $resultType) ?: false;

The expression return mysqli_fetch_array($result, $resultType) ?: false also could return the type false|null which is incompatible with the documented return type array|null.

    }

    /**
     * Fetch a result row as assoc array
     * @inheritDoc mysqli_fetch_assoc
     * @param [type] $result

The doc comment [type] at position 0 could not be parsed: Unknown type name '[' at position 0 in [type].

     * @return array|null
     */
    function mysql_fetch_assoc($result) /* : array|null */
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;

The expression return false returns the type false which is incompatible with the documented return type array|null.

        // @codeCoverageIgnoreEnd
      }

      return mysqli_fetch_assoc($result) ?: false;

The expression return mysqli_fetch_assoc($result) ?: false could also return false which is incompatible with the documented return type array|null. Did you maybe forget to handle an error condition?

    }

    function mysql_fetch_object($result, $class = null, array $params = array()) /* : object|null */
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      if ($class === null) {
        $object = mysqli_fetch_object($result);
      } else {
        $object = mysqli_fetch_object($result, $class, $params);
      }

      return $object ?: false;
    }

    function mysql_data_seek($result, $offset)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_data_seek($result, $offset);
    }

    function mysql_fetch_lengths($result) /* : array|*/
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_fetch_lengths($result);
    }

    function mysql_fetch_field($result) /* : object|*/
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_fetch_field($result);
    }

    function mysql_field_seek($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_field_seek($result, $field);
    }

    function mysql_free_result($result)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return mysqli_free_result($result);

Are you sure the usage of mysqli_free_result($result) is correct as it seems to always return null.

    }

    function mysql_field_name($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return \UniversalFramework\MySQL::mysqlFieldInfo($result, $field, 'name');
    }

    function mysql_field_table($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return \UniversalFramework\MySQL::mysqlFieldInfo($result, $field, 'table');
    }

    function mysql_field_len($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return \UniversalFramework\MySQL::mysqlFieldInfo($result, $field, 'length');
    }

    function mysql_field_type($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return \UniversalFramework\MySQL::mysqlFieldInfo($result, $field, 'type');
    }

    function mysql_field_flags($result, $field)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }
      return \UniversalFramework\MySQL::mysqlFieldInfo($result, $field, 'flags');
    }

    function mysql_escape_string($unescapedString)
    {
      if (\UniversalFramework\MySQL::$last_connection === null) {
        trigger_error(
          sprintf(
            '%s() is insecure; use mysql_real_escape_string() instead!',
            __FUNCTION__
          ),
          E_USER_NOTICE
        );

        return \UniversalFramework\MySQL::escapeString($unescapedString);
      }
      return mysql_real_escape_string($unescapedString, null);
    }

    function mysql_real_escape_string($unescapedString, \mysqli $link = null)
    {
      return mysqli_escape_string(\UniversalFramework\MySQL::getConnection($link), $unescapedString);

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_escape_string() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_stat(\mysqli $link = null)
    {
      return mysqli_stat(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_stat() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_thread_id(\mysqli $link = null)
    {
      return mysqli_thread_id(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_thread_id() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_client_encoding(\mysqli $link = null)
    {
      return mysqli_character_set_name(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_character_set_name() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_ping(\mysqli $link = null)
    {
      return mysqli_ping(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_ping() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_get_client_info(\mysqli $link = null)
    {
      return mysqli_get_client_info(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_get_client_info() does only seem to accept mysqli|null, maybe add an additional type check?

    }

    function mysql_get_host_info(\mysqli $link = null)
    {
      return mysqli_get_host_info(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_get_host_info() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_get_proto_info(\mysqli $link = null)
    {
      return mysqli_get_proto_info(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_get_proto_info() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_get_server_info(\mysqli $link = null)
    {
      return mysqli_get_server_info(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_get_server_info() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_info(\mysqli $link = null)
    {
      return mysqli_info(\UniversalFramework\MySQL::getConnection($link));

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_info() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_set_charset($charset, \mysqli $link = null)
    {
      return mysqli_set_charset(\UniversalFramework\MySQL::getConnection($link), $charset);

It seems like UniversalFramework\MySQL::getConnection($link) can also be of type false; however, parameter $mysql of mysqli_set_charset() does only seem to accept mysqli, maybe add an additional type check?

    }

    function mysql_db_name($result, $row, $field = 0)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      // Alias as per https://github.com/php/php-src/blob/PHP-5.6/ext/mysql/php_mysql.c#L319
      return mysql_result($result, $row, $field);
    }

    function mysql_tablename($result, $row)
    {
      if (!\UniversalFramework\MySQL::checkValidResult($result, __FUNCTION__)) {
        // @codeCoverageIgnoreStart
        return false;
        // @codeCoverageIgnoreEnd
      }

      // Alias as per http://lxr.php.net/xref/PHP_5_6/ext/mysql/php_mysql.c#321
      return mysql_result($result, $row, 'Table');
    }

    /* Aliases */

    function mysql_fieldname($result, $field)
    {
      return mysql_field_name($result, $field);
    }

    function mysql_fieldtable($result, $field)
    {
      return mysql_field_table($result, $field);
    }

    function mysql_fieldlen($result, $field)
    {
      return mysql_field_len($result, $field);
    }

    function mysql_fieldtype($result, $field)
    {
      return mysql_field_type($result, $field);
    }

    function mysql_fieldflags($result, $field)
    {
      return mysql_field_flags($result, $field);
    }

    function mysql_selectdb($databaseName, $link = null)
    {
      return mysql_select_db($databaseName, $link);
    }

    function mysql_freeresult($result)
    {
      return mysql_free_result($result);
    }

    function mysql_numfields($result)
    {
      return mysql_num_fields($result);
    }

    function mysql_numrows($result)
    {
      return mysql_num_rows($result);
    }

    function mysql_listdbs($link)
    {
      return mysql_list_dbs($link);
    }

    function mysql_listtables($databaseName, $link = null)
    {
      return mysql_list_tables($databaseName, $link);
    }

    function mysql_listfields($databaseName, $tableName, $link = null)
    {
      return mysql_list_fields($databaseName, $tableName, $link);
    }

    function mysql_dbname($result, $row, $field = 0)
    {
      return mysql_db_name($result, $row, $field);
    }

    function mysql_table_name($result, $row)
    {
      return mysql_tablename($result, $row);
    }
  }
}

namespace UniversalFramework {

  use mysqli;

  class MySQL
  {
    public static $last_connection = null;
    public static $connections = array();

    function __construct(mysqli $sql)
    {
      static::$last_connection = $sql;
    }

    /**
     * Get mysqli intances
     *
     * @param mysqli $link
     * @param function $func

The type UniversalFramework\function was not found. Maybe you did not declare it correctly or list all dependencies?

     * @return false|mysqli
     */
    public static function getConnection($link = null, $func = null)
    {
      if ($link !== null) {
        static::$last_connection = $link;
        return $link;
      }

      if (static::$last_connection === null) {
        $err = 'A link to the server could not be established';
        if ($func !== null) {
          $err = $func . '(): no MySQL-Link resource supplied';
        }
        trigger_error($err, E_USER_WARNING);
        return false;
      }

      return static::$last_connection;
    }

    public static function mysqlFieldInfo(\mysqli_result $result, $field, $what)
    {
      try {
        $field = mysqli_fetch_field_direct($result, $field);
      } catch (\Exception $e) {
        trigger_error(
          sprintf(
            'mysql_field_%s(): Field %d is invalid for MySQL result index %s',
            ($what !== 'length') ? $what : 'len',
            $field,

$field of type object is incompatible with the type double|integer|string expected by parameter $values of sprintf().

            spl_object_hash($result)
          ),
          E_USER_WARNING
        );
        // @codeCoverageIgnoreStart
        // PHPUnit turns the warning into an exception, so this never runs
        return false;
        // @codeCoverageIgnoreEnd
      }

      if ($what === 'type') {
        return static::getFieldType($field->type);
      }

      if ($what === 'flags') {
        return static::getFieldFlags($field->flags);
      }

      if (isset($field->{$what})) {
        return $field->{$what};
      }

      return false;
    }

    public static function checkValidResult($result, $function)
    {
      if (!($result instanceof \mysqli_result)) {
        if ($function !== 'mysql_fetch_object') {
          trigger_error(
            $function . '() expects parameter 1 to be resource, ' . strtolower(gettype($result)) . ' given',
            E_USER_WARNING
          );
        }

        if ($function === 'mysql_fetch_object') {
          trigger_error(
            $function . '(): supplied argument is not a valid MySQL result resource',
            E_USER_WARNING
          );
        }
        return false;
      }

      return true;
    }

    public static function escapeString($unescapedString)
    {
      $escapedString = '';
      for ($i = 0, $max = strlen($unescapedString); $i < $max; $i++) {
        $escapedString .= self::escapeChar($unescapedString[$i]);
      }

      return $escapedString;
    }

    protected static function getFieldFlags($what)
    {
      // Order of flags taken from http://lxr.php.net/xref/PHP_5_6/ext/mysql/php_mysql.c#2507
      $flags = array(
        MYSQLI_NOT_NULL_FLAG => 'not_null',
        MYSQLI_PRI_KEY_FLAG => 'primary_key',
        MYSQLI_UNIQUE_KEY_FLAG => 'unique_key',
        MYSQLI_MULTIPLE_KEY_FLAG => 'multiple_key',
        MYSQLI_BLOB_FLAG => 'blob',
        MYSQLI_UNSIGNED_FLAG => 'unsigned',
        MYSQLI_ZEROFILL_FLAG => 'zerofill',
        MYSQLI_BINARY_FLAG => 'binary',
        MYSQLI_ENUM_FLAG => 'enum',
        MYSQLI_SET_FLAG => 'set',
        MYSQLI_AUTO_INCREMENT_FLAG => 'auto_increment',
        MYSQLI_TIMESTAMP_FLAG => 'timestamp',
      );

      $fieldFlags = array();
      foreach ($flags as $flag => $value) {
        if ($what & $flag) {
          $fieldFlags[] = $value;
        }
      }

      return implode(' ', $fieldFlags);
    }

    protected static function getFieldType($what)
    {
      $types = array(
        MYSQLI_TYPE_STRING => 'string',
        MYSQLI_TYPE_VAR_STRING => 'string',
        MYSQLI_TYPE_ENUM => 'string',
        MYSQLI_TYPE_SET => 'string',

        MYSQLI_TYPE_LONG => 'int',
        MYSQLI_TYPE_TINY => 'int',
        MYSQLI_TYPE_SHORT => 'int',
        MYSQLI_TYPE_INT24 => 'int',
        MYSQLI_TYPE_CHAR => 'int',
        MYSQLI_TYPE_LONGLONG => 'int',

        MYSQLI_TYPE_DECIMAL => 'real',
        MYSQLI_TYPE_FLOAT => 'real',
        MYSQLI_TYPE_DOUBLE => 'real',
        MYSQLI_TYPE_NEWDECIMAL => 'real',

        MYSQLI_TYPE_TINY_BLOB => 'blob',
        MYSQLI_TYPE_MEDIUM_BLOB => 'blob',
        MYSQLI_TYPE_LONG_BLOB => 'blob',
        MYSQLI_TYPE_BLOB => 'blob',

        MYSQLI_TYPE_NEWDATE => 'date',
        MYSQLI_TYPE_DATE => 'date',
        MYSQLI_TYPE_TIME => 'time',
        MYSQLI_TYPE_YEAR => 'year',
        MYSQLI_TYPE_DATETIME => 'datetime',
        MYSQLI_TYPE_TIMESTAMP => 'timestamp',

        MYSQLI_TYPE_NULL => 'null',

        MYSQLI_TYPE_GEOMETRY => 'geometry',
      );

      return isset($types[$what]) ? $types[$what] : 'unknown';
    }

    protected static function escapeChar($char)
    {
      switch ($char) {
        case "\0":
          $esc = "\\0";
          break;
        case "\n":
          $esc = "\\n";
          break;
        case "\r":
          $esc = "\\r";
          break;
        case '\\':
        case '\'':
        case '"':
          $esc = "\\{$char}";
          break;
        case "\032":
          $esc = "\\Z";
          break;
        default:
          $esc = $char;
          break;
      }

      return $esc;
    }
  }
}