WordPress Version: 6.3
/**
* Adds a base URL to relative links in passed content.
*
* By default, this function supports the 'src' and 'href' attributes.
* However, this can be modified via the `$attrs` parameter.
*
* @since 2.7.0
*
* @global string $_links_add_base
*
* @param string $content String to search for links in.
* @param string $base The base URL to prefix to links.
* @param array $attrs The attributes which should be processed.
* @return string The processed content.
*/
function links_add_base_url($content, $base, $attrs = array('src', 'href'))
{
global $_links_add_base;
$_links_add_base = $base;
$attrs = implode('|', (array) $attrs);
return preg_replace_callback("!({$attrs})=(['\"])(.+?)\\2!i", '_links_add_base', $content);
}