Escaping for textarea values while leaving both double and single quotes unconverted.

functions.php

<?php
/**
 * Escaping for textarea values while leaving both double and single quotes unconverted.
 *
 * @param string $text
 * @return string
 */
function theme_slug_esc_text( $text ) {
	return htmlspecialchars( $text, ENT_NOQUOTES, get_option( 'blog_charset' ) );
}