diff --git a/do.php b/do.php
index d644674..fef97ff 100755
--- a/do.php
+++ b/do.php
@@ -417,7 +417,7 @@ elseif (ig('down') || ig('downf') ||
         }
     }
 
-    if (! ($size = @kleeja_filesize($path_file)))
+    if (! ($size = @filesize($path_file)))
     {
         $size = $d_size;
     }
diff --git a/includes/adm/g_users.php b/includes/adm/g_users.php
index c2b2def..a2b5d2e 100755
--- a/includes/adm/g_users.php
+++ b/includes/adm/g_users.php
@@ -237,7 +237,7 @@ elseif (ip('newuser'))
     if (empty($ERRORS))
     {
         $name                 = (string) $SQL->escape(trim(p('lname')));
-        $user_salt            = (string) substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+        $user_salt            = (string) substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
         $pass                 = (string) $usrcp->kleeja_hash_password($SQL->escape(trim(p('lpass'))) . $user_salt);
         $mail                 = (string) trim(strtolower(p('lmail')));
         $clean_name           = (string) $usrcp->cleanusername($name);
@@ -349,7 +349,7 @@ if (ip('edituser'))
     }
     elseif (trim(p('l_pass')) != '')
     {
-        $user_salt       = substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+        $user_salt       = substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
         $pass            = "password = '" . $usrcp->kleeja_hash_password(trim(p('l_pass')) . $user_salt) . "', password_salt='" . $user_salt . "',";
     }
 
diff --git a/includes/auth_integration/api.php b/includes/auth_integration/api.php
index 5122521..855c23a 100755
--- a/includes/auth_integration/api.php
+++ b/includes/auth_integration/api.php
@@ -37,7 +37,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
 
     // @see file : docs/kleeja_(vb,mysmartbb,phpbb)_api.txt
 
-    $api_http_query = 'api_key=' . kleeja_base64_encode($script_api_key) . '&' . ($hashed ? 'userid' : 'username') . '=' . urlencode($name) . '&pass=' . kleeja_base64_encode($pass);
+    $api_http_query = 'api_key=' . base64_encode($script_api_key) . '&' . ($hashed ? 'userid' : 'username') . '=' . urlencode($name) . '&pass=' . base64_encode($pass);
     //if only username, let tell him in the query
     $api_http_query .= $return_username ? '&return_username=1' : '';
 
@@ -56,7 +56,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
     //split the data , the first one is always 0 or 1
     //0 : error
     //1: ok
-    $user_info = explode('%|%', kleeja_base64_decode($remote_data));
+    $user_info = explode('%|%', base64_decode($remote_data));
 
     //omg, it's 0 , 0 : error, lets die here
     if ((int) $user_info[0] == 0)
@@ -88,7 +88,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
     //and this must be filled with user data comming from url
     $userinfo             = [];
     $userinfo['group_id'] = GROUP_ID;
-    $user_y               = kleeja_base64_encode(serialize(['id'=>USER_ID, 'name'=>USER_NAME, 'mail'=>USER_MAIL, 'last_visit'=>time()]));
+    $user_y               = base64_encode(serialize(['id'=>USER_ID, 'name'=>USER_NAME, 'mail'=>USER_MAIL, 'last_visit'=>time()]));
 
 
     //add cookies
diff --git a/includes/auth_integration/phpbb.php b/includes/auth_integration/phpbb.php
index 766741e..01ae9f8 100755
--- a/includes/auth_integration/phpbb.php
+++ b/includes/auth_integration/phpbb.php
@@ -112,7 +112,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
         $result2 = $SQLBB->build($query2);
         while ($row=$SQLBB->fetch_array($result2))
         {
-            $SQLBB->freeresult($result2); 
+            $SQLBB->freeresult($result2);
 
             if ($return_name)
             {
@@ -164,7 +164,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
                 $userinfo             = $row;
                 $userinfo['group_id'] = ($row[$row_leve] == $admin_level ? '1' : '3');
 
-                $user_y = kleeja_base64_encode(serialize(['id'=>$row['user_id'], 'name'=>$row['username'], 'mail'=>$row['user_email'], 'last_visit'=>time()]));
+                $user_y = base64_encode(serialize(['id'=>$row['user_id'], 'name'=>$row['username'], 'mail'=>$row['user_email'], 'last_visit'=>time()]));
 
                 if (! $hashed && ! $loginadm)
                 {
diff --git a/includes/auth_integration/vb.php b/includes/auth_integration/vb.php
index 105a4cd..794482b 100755
--- a/includes/auth_integration/vb.php
+++ b/includes/auth_integration/vb.php
@@ -67,7 +67,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
                 $forum_srv .= ':' . $config['MasterServer']['port'];
             }
 
-            //some people change their db charset 
+            //some people change their db charset
             if (isset($config['Mysqli']['charset']))
             {
                 $forum_db_charset = $config['Mysqli']['charset'];
@@ -89,7 +89,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
         $forum_pass      = $script_pass;
         $forum_prefix    = $script_prefix;
 
-        //some people change their db charset 
+        //some people change their db charset
         if (isset($script_db_charset))
         {
             $forum_db_charset = $script_db_charset;
@@ -120,7 +120,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
     $name = empty($script_cp1256) || ! $script_cp1256 || $hashed ? $name : $usrcp->kleeja_utf8($name, false);
 
     $query_salt = [
-        'SELECT'       => $hashed ? '*' : ($isVB5 ? 'token' : 'salt'), 
+        'SELECT'       => $hashed ? '*' : ($isVB5 ? 'token' : 'salt'),
         'FROM'         => "`{$forum_prefix}user`",
     ];
 
@@ -147,7 +147,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
 
             if (! $hashed)
             {
-                $pass = ! $isVB5 
+                $pass = ! $isVB5
                         ? md5(md5($pass) . $row1['salt'])  // without normal md5
                         : crypt(md5($pass), $row1['token']);
 
@@ -176,18 +176,18 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
 
                         $userinfo             = $row;
                         $userinfo['group_id'] =  ($row['usergroupid'] == 6 ? 1 : 3);
-                        $user_y               = kleeja_base64_encode(serialize(['id'=>$row['userid'], 'name'=>USER_NAME, 'mail'=>$row['email'], 'last_visit'=>time()]));
+                        $user_y               = base64_encode(serialize(['id'=>$row['userid'], 'name'=>USER_NAME, 'mail'=>$row['email'], 'last_visit'=>time()]));
 
                         $hash_key_expire = sha1(md5($config['h_key'] . ($isVB5 ? $row['token'] : $row['password'])) . $expire);
 
                         if (! $loginadm)
                         {
                             $usrcp->kleeja_set_cookie('ulogu', $usrcp->en_de_crypt(
-                                                    $row['userid'] . '|' . 
-                                                    ($isVB5 ? $row['token'] : $row['password']) . '|' . 
-                                                    $expire . '|' . 
-                                                    $hash_key_expire . '|' . 
-                                                    ($row['usergroupid'] == 6 ? 1 : 3) . '|' . 
+                                                    $row['userid'] . '|' .
+                                                    ($isVB5 ? $row['token'] : $row['password']) . '|' .
+                                                    $expire . '|' .
+                                                    $hash_key_expire . '|' .
+                                                    ($row['usergroupid'] == 6 ? 1 : 3) . '|' .
                                                     $user_y
                                                 ), $expire);
                         }
@@ -217,7 +217,7 @@ function kleeja_auth_login ($name, $pass, $hashed = false, $expire, $loginadm =
             }
         }//whil1
 
-        $SQLVB->freeresult($result_salt); 
+        $SQLVB->freeresult($result_salt);
 
         unset($pass);
         $SQLVB->close();
diff --git a/includes/functions.php b/includes/functions.php
index db69801..9e050be 100755
--- a/includes/functions.php
+++ b/includes/functions.php
@@ -216,7 +216,7 @@ function kleeja_get_page()
  */
 function _sm_mk_utf8($text)
 {
-    return '=?UTF-8?B?' . kleeja_base64_encode($text) . '?=';
+    return '=?UTF-8?B?' . base64_encode($text) . '?=';
 }
 
 /**
diff --git a/includes/functions_alternative.php b/includes/functions_alternative.php
index e1381e4..d2babea 100755
--- a/includes/functions_alternative.php
+++ b/includes/functions_alternative.php
@@ -9,8 +9,8 @@
 
 
 /**
-* After a lot of work, we faced many hosts who use a old PHP version, or 
-* they disabled many general functions ... 
+* After a lot of work, we faced many hosts who use a old PHP version, or
+* they disabled many general functions ...
 * so, this file contains those type of functions.
 */
 
@@ -21,207 +21,3 @@ if (! defined('IN_COMMON'))
     exit();
 }
 
-
-if (! function_exists('htmlspecialchars_decode'))
-{
-    function htmlspecialchars_decode($string, $style=ENT_COMPAT)
-    {
-        $translation = array_flip(get_html_translation_table(HTML_SPECIALCHARS, $style));
-
-        if ($style === ENT_QUOTES)
-        {
-            $translation['''] = '\'';
-        }
-        return strtr($string, $translation);
-    }
-}
-
-//
-//http://us2.php.net/manual/en/function.str-split.php#84891
-if (! function_exists('str_split'))
-{
-    function str_split($string, $string_length=1)
-    {
-        if (strlen($string) > $string_length || ! $string_length)
-        {
-            do
-            {
-                $c          = strlen($string);
-                $parts[]    = substr($string, 0, $string_length);
-                $string     = substr($string, $string_length);
-            } while ($string !== false);
-        }
-        else
-        {
-            $parts = [$string];
-        }
-        return $parts;
-    }
-}
-
-//Custom base64_* functions
-function kleeja_base64_encode($str = '')
-{
-    return function_exists('base64_encode') ? base64_encode($str) : base64encode($str);
-}
-function kleeja_base64_decode($str = '')
-{
-    return function_exists('base64_decode') ? base64_decode($str) : base64decode($str);
-}
-
-//http://www.php.net/manual/en/function.base64-encode.php#63270
-function base64encode($string = '')
-{
-    if (! function_exists('convert_binary_str'))
-    {
-        function convert_binary_str($string)
-        {
-            if (strlen($string) <= 0)
-            {
-                return;
-            }
-
-            $tmp = decbin(ord($string[0]));
-            $tmp = str_repeat('0', 8-strlen($tmp)) . $tmp;
-            return $tmp . convert_binary_str(substr($string, 1));
-        }
-    }
-
-    $binval = convert_binary_str($string);
-    $final  = '';
-    $start  = 0;
-
-    while ($start < strlen($binval))
-    {
-        if (strlen(substr($binval, $start)) < 6)
-        {
-            $binval .= str_repeat('0', 6-strlen(substr($binval, $start)));
-        }
-        $tmp = bindec(substr($binval, $start, 6));
-
-        if ($tmp < 26)
-        {
-            $final .= chr($tmp+65);
-        }
-        elseif ($tmp > 25 && $tmp < 52)
-        {
-            $final .= chr($tmp+71);
-        }
-        elseif ($tmp == 62)
-        {
-            $final .= '+';
-        }
-        elseif ($tmp == 63)
-        {
-            $final .= '/';
-        }
-        elseif (! $tmp)
-        {
-            $final .= 'A';
-        }
-        else
-        {
-            $final .= chr($tmp-4);
-        }
-        $start += 6;
-    }
-
-    if (strlen($final)%4>0)
-    {
-        $final .= str_repeat('=', 4-strlen($final)%4);
-    }
-    return $final;
-}
-
-
-
-function base64decode($str)
-{
-    $len        = strlen($str);
-    $ret        = '';
-    $b64        = [];
-    $base64     = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
-    $len_base64 = strlen($base64);
-
-    for ($i = 0; $i < 256; $i++)
-    {
-        $b64[$i] = 0;
-    }
-
-    for ($i = 0; $i < $len_base64; $i++)
-    {
-        $b64[ord($base64[$i])] = $i;
-    }
-
-    for ($j=0;$j<$len;$j+=4)
-    {
-        for ($i = 0; $i < 4; $i++)
-        {
-            $c     = ord($str[$j+$i]);
-            $a[$i] = $c;
-            $b[$i] = $b64[$c];
-        }
-
-        $o[0] = ($b[0] << 2) | ($b[1] >> 4);
-        $o[1] = ($b[1] << 4) | ($b[2] >> 2);
-        $o[2] = ($b[2] << 6) | $b[3];
-
-        if ($a[2] == ord('='))
-        {
-            $i = 1;
-        }
-        elseif ($a[3] == ord('='))
-        {
-            $i = 2;
-        }
-        else
-        {
-            $i = 3;
-        }
-
-        for ($k=0;$k<$i;$k++)
-        {
-            $ret .= chr((int) $o[$k] & 255);
-        }
-
-        if ($i < 3)
-        {
-            break;
-        }
-    }
-
-    return $ret;
-}
-
-if (! function_exists('filesize'))
-{
-    function kleeja_filesize($filename)
-    {
-        $a = fopen($filename, 'r'); 
-        fseek($a, 0, SEEK_END); 
-        $filesize = ftell($a); 
-        fclose($a);
-        return $filesize;
-    }
-}
-else
-{
-    function kleeja_filesize($filename)
-    {
-        return filesize($filename);
-    }
-}
-
-
-if (! function_exists('array_column'))
-{
-    function array_column($array, $column_name)
-    {
-        return array_map(
-                                function($element) use ($column_name) {
-                                    return $element[$column_name];
-                                },
-                                array_values($array)
-                    );
-    }
-}
diff --git a/includes/up_helpers/others.php b/includes/up_helpers/others.php
index 71a663a..86e23f2 100755
--- a/includes/up_helpers/others.php
+++ b/includes/up_helpers/others.php
@@ -17,7 +17,7 @@ if (! defined('IN_COMMON'))
 
 /**
  * checking the safety and validity of sub-extension of given file
- * 
+ *
  * @param mixed $filename
  */
 function ext_check_safe($filename)
@@ -256,7 +256,7 @@ function check_mime_type($given_file_mime, $file_ext, $file_path)
 
     //if normal checks failed!
 
-    if (@kleeja_filesize($file_path) > 6*(1000*1024))
+    if (@filesize($file_path) > 6*(1000*1024))
     {
         return true;
     }
@@ -285,7 +285,7 @@ function check_mime_type($given_file_mime, $file_ext, $file_path)
 
 
 /**
- * to prevent flooding at uploading  
+ * to prevent flooding at uploading
  * @param mixed $user_id
  */
 function user_is_flooding($user_id = '-1')
@@ -307,9 +307,9 @@ function user_is_flooding($user_id = '-1')
         return false;
     }
 
-    //In my point of view I see 30 seconds is not bad rate to stop flooding .. 
-    //even though this minimum rate sometime isn't enough to protect Kleeja from flooding attacks 
-    $time = time() - ($user_id == '-1' ? $config['guestsectoupload'] : $config['usersectoupload']); 
+    //In my point of view I see 30 seconds is not bad rate to stop flooding ..
+    //even though this minimum rate sometime isn't enough to protect Kleeja from flooding attacks
+    $time = time() - ($user_id == '-1' ? $config['guestsectoupload'] : $config['usersectoupload']);
 
     $query = [
         'SELECT'          => 'f.time',
diff --git a/includes/usr.php b/includes/usr.php
index fdef041..9963e88 100755
--- a/includes/usr.php
+++ b/includes/usr.php
@@ -106,7 +106,7 @@ class usrcp
                     if ($row['password'] == $passmd5)
                     {
                         ////new salt
-                        $new_salt = substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+                        $new_salt = substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
                         ////new password hash
                         $new_password = $this->kleeja_hash_password(trim($pass) . $new_salt);
 
@@ -145,7 +145,7 @@ class usrcp
                 //all user fileds info
                 $userinfo = $row;
 
-                $user_y = kleeja_base64_encode(serialize(['id'=>$row['id'], 'name'=>$row['name'], 'mail'=>$row['mail'], 'last_visit'=>$row['last_visit']]));
+                $user_y = base64_encode(serialize(['id'=>$row['id'], 'name'=>$row['name'], 'mail'=>$row['mail'], 'last_visit'=>$row['last_visit']]));
 
                 if (! $hashed && ! $loginadm)
                 {
@@ -272,11 +272,6 @@ class usrcp
     //clean usernames
     public function cleanusername($uname)
     {
-        if (! function_exists('kleeja_base64_decode'))
-        {
-            include_once PATH . 'includes/functions_alternative.php';
-        }
-
         is_array($plugin_run_result = Plugins::getInstance()->run('cleanusername_func_usr_class', get_defined_vars())) ? extract($plugin_run_result) : null; //run hook
 
         static $arabic_t = [];
@@ -288,7 +283,7 @@ class usrcp
         if (empty($arabic_t))
         {
             //Arabic chars must be stay in utf8 format, so we encoded them
-            $arabic_t = unserialize(kleeja_base64_decode('YToyOntpOjA7YToxMjp7aTowO3M6Mjoi2KMiO2k6MTtzOjI6ItilIjtpOjI7czoyOiLYpCI7aTozO3M6Mjoi2YAiO2k6NDtzOjI6Itm' .
+            $arabic_t = unserialize(base64_decode('YToyOntpOjA7YToxMjp7aTowO3M6Mjoi2KMiO2k6MTtzOjI6ItilIjtpOjI7czoyOiLYpCI7aTozO3M6Mjoi2YAiO2k6NDtzOjI6Itm' .
             'LIjtpOjU7czoyOiLZjCI7aTo2O3M6Mjoi2Y8iO2k6NztzOjI6ItmOIjtpOjg7czoyOiLZkCI7aTo5O3M6Mjoi2ZIiO2k6MTA7czoyOiLYoiI7aToxMTtzOjI6ItimIjt9aToxO' .
             '2E6MTI6e2k6MDtzOjI6ItinIjtpOjE7czoyOiLYpyI7aToyO3M6Mjoi2YgiO2k6MztzOjA6IiI7aTo0O3M6MDoiIjtpOjU7czowOiIiO2k6NjtzOjA6IiI7aTo3O3M6MDoiIjt' .
             'pOjg7czowOiIiO2k6OTtzOjA6IiI7aToxMDtzOjI6ItinIjtpOjExO3M6Mjoi2YkiO319'));
@@ -381,7 +376,7 @@ class usrcp
         switch ($type)
         {
             case 1:
-                $data = str_replace('=', '_', kleeja_base64_encode($data));
+                $data = str_replace('=', '_', base64_encode($data));
                 $data = strtr($data, $txt);
 
             break;
@@ -390,7 +385,7 @@ class usrcp
                 $txtx = array_flip($txt);
                 $txtx = array_reverse($txtx, true);
                 $data = strtr($data, $txtx);
-                $data = kleeja_base64_decode(str_replace('_', '=', $data));
+                $data = base64_decode(str_replace('_', '=', $data));
 
             break;
         }
@@ -445,7 +440,7 @@ class usrcp
                 {
                     if (! empty($u_info))
                     {
-                        $userinfo             = unserialize(kleeja_base64_decode($u_info));
+                        $userinfo             = unserialize(base64_decode($u_info));
                         $userinfo['group_id'] = $group_id;
                         $userinfo['password'] = $hashed_password;
 
diff --git a/install/install.php b/install/install.php
index 74e99d0..e28ca37 100755
--- a/install/install.php
+++ b/install/install.php
@@ -208,7 +208,7 @@ case 'data' :
         include_once PATH . 'includes/functions_alternative.php';
         $usrcp = new usrcp;
 
-        $user_salt                 = substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+        $user_salt                 = substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
         $user_pass                 = $usrcp->kleeja_hash_password(p('password') . $user_salt);
         $user_name                 = $SQL->escape(p('username'));
         $user_mail                 = $SQL->escape(p('email'));
diff --git a/install/quick.php b/install/quick.php
index c3baa50..3477c43 100644
--- a/install/quick.php
+++ b/install/quick.php
@@ -83,7 +83,7 @@ include_once PATH . 'includes/functions_alternative.php';
 
 $usrcp                     = new usrcp;
 $password                  = ! empty($cli_options['password']) ? $cli_options['password'] : mt_rand();
-$user_salt                 = substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+$user_salt                 = substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
 $user_pass                 = $usrcp->kleeja_hash_password($password . $user_salt);
 $user_name                 = $clean_name = 'admin';
 $user_mail                 = $config_sitemail = 'admin@example.com';
diff --git a/ucp.php b/ucp.php
index 3223fd1..6d74e41 100755
--- a/ucp.php
+++ b/ucp.php
@@ -232,7 +232,7 @@ switch (g('go'))
             if (empty($ERRORS))
             {
                 $name              = (string) $SQL->escape(trim(p('lname')));
-                $user_salt         = (string) substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+                $user_salt         = (string) substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
                 $pass              = (string) $usrcp->kleeja_hash_password($SQL->escape(trim(p('lpass'))) . $user_salt);
                 $mail              = (string) strtolower(trim($SQL->escape(p('lmail'))));
                 $session_id        = (string) session_id();
@@ -701,7 +701,7 @@ switch (g('go'))
             //no errors , do it
             if (empty($ERRORS))
             {
-                $user_salt        = substr(kleeja_base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
+                $user_salt        = substr(base64_encode(pack('H*', sha1(mt_rand()))), 0, 7);
                 $mail             = $new_mail ? "mail='" . $SQL->escape(strtolower(trim(p('pmail')))) . "'" : '';
                 $showmyfile       = p('show_my_filecp', 'int') != $show_my_filecp ?  ($mail == '' ? '': ',') . "show_my_filecp='" . p('show_my_filecp', 'int') . "'" : '';
                 $pass             = ! empty(p('ppass_new')) ? ($showmyfile != ''  || $mail != '' ? ',' : '') . "password='" . $usrcp->kleeja_hash_password($SQL->escape(p('ppass_new')) . $user_salt) .